Annotation of elwix/files/sqlite/dist/sqlite3.h, revision 1.6.2.1

1.2       misho       1: /*
1.5       misho       2: ** 2001-09-15
1.2       misho       3: **
                      4: ** The author disclaims copyright to this source code.  In place of
                      5: ** a legal notice, here is a blessing:
                      6: **
                      7: **    May you do good and not evil.
                      8: **    May you find forgiveness for yourself and forgive others.
                      9: **    May you share freely, never taking more than you give.
                     10: **
                     11: *************************************************************************
                     12: ** This header file defines the interface that the SQLite library
                     13: ** presents to client programs.  If a C-function, structure, datatype,
                     14: ** or constant definition does not appear in this file, then it is
                     15: ** not a published API of SQLite, is subject to change without
                     16: ** notice, and should not be referenced by programs that use SQLite.
                     17: **
                     18: ** Some of the definitions that are in this file are marked as
                     19: ** "experimental".  Experimental interfaces are normally new
                     20: ** features recently added to SQLite.  We do not anticipate changes
                     21: ** to experimental interfaces but reserve the right to make minor changes
                     22: ** if experience from use "in the wild" suggest such changes are prudent.
                     23: **
                     24: ** The official C-language API documentation for SQLite is derived
                     25: ** from comments in this file.  This file is the authoritative source
1.4       misho      26: ** on how SQLite interfaces are supposed to operate.
1.2       misho      27: **
                     28: ** The name of this file under configuration management is "sqlite.h.in".
                     29: ** The makefile makes some minor changes to this file (such as inserting
                     30: ** the version number) and changes its name to "sqlite3.h" as
                     31: ** part of the build process.
                     32: */
1.4       misho      33: #ifndef SQLITE3_H
                     34: #define SQLITE3_H
1.2       misho      35: #include <stdarg.h>     /* Needed for the definition of va_list */
                     36: 
                     37: /*
                     38: ** Make sure we can call this stuff from C++.
                     39: */
                     40: #ifdef __cplusplus
                     41: extern "C" {
                     42: #endif
                     43: 
                     44: 
                     45: /*
1.6.2.1 ! misho      46: ** Facilitate override of interface linkage and calling conventions.
        !            47: ** Be aware that these macros may not be used within this particular
        !            48: ** translation of the amalgamation and its associated header file.
        !            49: **
        !            50: ** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the
        !            51: ** compiler that the target identifier should have external linkage.
        !            52: **
        !            53: ** The SQLITE_CDECL macro is used to set the calling convention for
        !            54: ** public functions that accept a variable number of arguments.
        !            55: **
        !            56: ** The SQLITE_APICALL macro is used to set the calling convention for
        !            57: ** public functions that accept a fixed number of arguments.
        !            58: **
        !            59: ** The SQLITE_STDCALL macro is no longer used and is now deprecated.
        !            60: **
        !            61: ** The SQLITE_CALLBACK macro is used to set the calling convention for
        !            62: ** function pointers.
        !            63: **
        !            64: ** The SQLITE_SYSAPI macro is used to set the calling convention for
        !            65: ** functions provided by the operating system.
        !            66: **
        !            67: ** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and
        !            68: ** SQLITE_SYSAPI macros are used only when building for environments
        !            69: ** that require non-default calling conventions.
1.2       misho      70: */
                     71: #ifndef SQLITE_EXTERN
                     72: # define SQLITE_EXTERN extern
                     73: #endif
                     74: #ifndef SQLITE_API
                     75: # define SQLITE_API
                     76: #endif
1.4       misho      77: #ifndef SQLITE_CDECL
                     78: # define SQLITE_CDECL
                     79: #endif
                     80: #ifndef SQLITE_APICALL
                     81: # define SQLITE_APICALL
                     82: #endif
                     83: #ifndef SQLITE_STDCALL
                     84: # define SQLITE_STDCALL SQLITE_APICALL
                     85: #endif
                     86: #ifndef SQLITE_CALLBACK
                     87: # define SQLITE_CALLBACK
                     88: #endif
                     89: #ifndef SQLITE_SYSAPI
                     90: # define SQLITE_SYSAPI
                     91: #endif
1.2       misho      92: 
                     93: /*
                     94: ** These no-op macros are used in front of interfaces to mark those
                     95: ** interfaces as either deprecated or experimental.  New applications
1.4       misho      96: ** should not use deprecated interfaces - they are supported for backwards
1.2       misho      97: ** compatibility only.  Application writers should be aware that
                     98: ** experimental interfaces are subject to change in point releases.
                     99: **
                    100: ** These macros used to resolve to various kinds of compiler magic that
                    101: ** would generate warning messages when they were used.  But that
                    102: ** compiler magic ended up generating such a flurry of bug reports
                    103: ** that we have taken it all out and gone back to using simple
                    104: ** noop macros.
                    105: */
                    106: #define SQLITE_DEPRECATED
                    107: #define SQLITE_EXPERIMENTAL
                    108: 
                    109: /*
                    110: ** Ensure these symbols were not defined by some previous header file.
                    111: */
                    112: #ifdef SQLITE_VERSION
                    113: # undef SQLITE_VERSION
                    114: #endif
                    115: #ifdef SQLITE_VERSION_NUMBER
                    116: # undef SQLITE_VERSION_NUMBER
                    117: #endif
                    118: 
                    119: /*
                    120: ** CAPI3REF: Compile-Time Library Version Numbers
                    121: **
                    122: ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
                    123: ** evaluates to a string literal that is the SQLite version in the
                    124: ** format "X.Y.Z" where X is the major version number (always 3 for
                    125: ** SQLite3) and Y is the minor version number and Z is the release number.)^
                    126: ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
                    127: ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
                    128: ** numbers used in [SQLITE_VERSION].)^
                    129: ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
                    130: ** be larger than the release from which it is derived.  Either Y will
                    131: ** be held constant and Z will be incremented or else Y will be incremented
                    132: ** and Z will be reset to zero.
                    133: **
1.5       misho     134: ** Since [version 3.6.18] ([dateof:3.6.18]),
                    135: ** SQLite source code has been stored in the
1.2       misho     136: ** <a href="http://www.fossil-scm.org/">Fossil configuration management
                    137: ** system</a>.  ^The SQLITE_SOURCE_ID macro evaluates to
                    138: ** a string which identifies a particular check-in of SQLite
                    139: ** within its configuration management system.  ^The SQLITE_SOURCE_ID
1.5       misho     140: ** string contains the date and time of the check-in (UTC) and a SHA1
                    141: ** or SHA3-256 hash of the entire source tree.  If the source code has
                    142: ** been edited in any way since it was last checked in, then the last
                    143: ** four hexadecimal digits of the hash may be modified.
1.2       misho     144: **
                    145: ** See also: [sqlite3_libversion()],
                    146: ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
                    147: ** [sqlite_version()] and [sqlite_source_id()].
                    148: */
1.6.2.1 ! misho     149: #define SQLITE_VERSION        "3.43.1"
        !           150: #define SQLITE_VERSION_NUMBER 3043001
        !           151: #define SQLITE_SOURCE_ID      "2023-09-11 12:01:27 2d3a40c05c49e1a49264912b1a05bc2143ac0e7c3df588276ce80a4cbc9bd1b0"
1.2       misho     152: 
                    153: /*
                    154: ** CAPI3REF: Run-Time Library Version Numbers
1.5       misho     155: ** KEYWORDS: sqlite3_version sqlite3_sourceid
1.2       misho     156: **
                    157: ** These interfaces provide the same information as the [SQLITE_VERSION],
                    158: ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
                    159: ** but are associated with the library instead of the header file.  ^(Cautious
                    160: ** programmers might include assert() statements in their application to
                    161: ** verify that values returned by these interfaces match the macros in
1.4       misho     162: ** the header, and thus ensure that the application is
1.2       misho     163: ** compiled with matching library and header files.
                    164: **
                    165: ** <blockquote><pre>
                    166: ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
1.5       misho     167: ** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
1.2       misho     168: ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
                    169: ** </pre></blockquote>)^
                    170: **
                    171: ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
                    172: ** macro.  ^The sqlite3_libversion() function returns a pointer to the
                    173: ** to the sqlite3_version[] string constant.  The sqlite3_libversion()
                    174: ** function is provided for use in DLLs since DLL users usually do not have
                    175: ** direct access to string constants within the DLL.  ^The
                    176: ** sqlite3_libversion_number() function returns an integer equal to
1.5       misho     177: ** [SQLITE_VERSION_NUMBER].  ^(The sqlite3_sourceid() function returns
                    178: ** a pointer to a string constant whose value is the same as the
                    179: ** [SQLITE_SOURCE_ID] C preprocessor macro.  Except if SQLite is built
                    180: ** using an edited copy of [the amalgamation], then the last four characters
                    181: ** of the hash might be different from [SQLITE_SOURCE_ID].)^
1.2       misho     182: **
                    183: ** See also: [sqlite_version()] and [sqlite_source_id()].
                    184: */
                    185: SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
                    186: SQLITE_API const char *sqlite3_libversion(void);
                    187: SQLITE_API const char *sqlite3_sourceid(void);
                    188: SQLITE_API int sqlite3_libversion_number(void);
                    189: 
                    190: /*
                    191: ** CAPI3REF: Run-Time Library Compilation Options Diagnostics
                    192: **
1.5       misho     193: ** ^The sqlite3_compileoption_used() function returns 0 or 1
                    194: ** indicating whether the specified option was defined at
                    195: ** compile time.  ^The SQLITE_ prefix may be omitted from the
                    196: ** option name passed to sqlite3_compileoption_used().
1.2       misho     197: **
                    198: ** ^The sqlite3_compileoption_get() function allows iterating
                    199: ** over the list of options that were defined at compile time by
                    200: ** returning the N-th compile time option string.  ^If N is out of range,
1.5       misho     201: ** sqlite3_compileoption_get() returns a NULL pointer.  ^The SQLITE_
                    202: ** prefix is omitted from any strings returned by
1.2       misho     203: ** sqlite3_compileoption_get().
                    204: **
                    205: ** ^Support for the diagnostic functions sqlite3_compileoption_used()
1.5       misho     206: ** and sqlite3_compileoption_get() may be omitted by specifying the
1.2       misho     207: ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
                    208: **
                    209: ** See also: SQL functions [sqlite_compileoption_used()] and
                    210: ** [sqlite_compileoption_get()] and the [compile_options pragma].
                    211: */
                    212: #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
                    213: SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
                    214: SQLITE_API const char *sqlite3_compileoption_get(int N);
1.5       misho     215: #else
                    216: # define sqlite3_compileoption_used(X) 0
                    217: # define sqlite3_compileoption_get(X)  ((void*)0)
1.2       misho     218: #endif
                    219: 
                    220: /*
                    221: ** CAPI3REF: Test To See If The Library Is Threadsafe
                    222: **
                    223: ** ^The sqlite3_threadsafe() function returns zero if and only if
                    224: ** SQLite was compiled with mutexing code omitted due to the
                    225: ** [SQLITE_THREADSAFE] compile-time option being set to 0.
                    226: **
                    227: ** SQLite can be compiled with or without mutexes.  When
                    228: ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
                    229: ** are enabled and SQLite is threadsafe.  When the
1.5       misho     230: ** [SQLITE_THREADSAFE] macro is 0,
1.2       misho     231: ** the mutexes are omitted.  Without the mutexes, it is not safe
                    232: ** to use SQLite concurrently from more than one thread.
                    233: **
                    234: ** Enabling mutexes incurs a measurable performance penalty.
                    235: ** So if speed is of utmost importance, it makes sense to disable
                    236: ** the mutexes.  But for maximum safety, mutexes should be enabled.
                    237: ** ^The default behavior is for mutexes to be enabled.
                    238: **
                    239: ** This interface can be used by an application to make sure that the
                    240: ** version of SQLite that it is linking against was compiled with
                    241: ** the desired setting of the [SQLITE_THREADSAFE] macro.
                    242: **
                    243: ** This interface only reports on the compile-time mutex setting
                    244: ** of the [SQLITE_THREADSAFE] flag.  If SQLite is compiled with
                    245: ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
                    246: ** can be fully or partially disabled using a call to [sqlite3_config()]
                    247: ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
1.4       misho     248: ** or [SQLITE_CONFIG_SERIALIZED].  ^(The return value of the
1.2       misho     249: ** sqlite3_threadsafe() function shows only the compile-time setting of
                    250: ** thread safety, not any run-time changes to that setting made by
                    251: ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
                    252: ** is unchanged by calls to sqlite3_config().)^
                    253: **
                    254: ** See the [threading mode] documentation for additional information.
                    255: */
                    256: SQLITE_API int sqlite3_threadsafe(void);
                    257: 
                    258: /*
                    259: ** CAPI3REF: Database Connection Handle
                    260: ** KEYWORDS: {database connection} {database connections}
                    261: **
                    262: ** Each open SQLite database is represented by a pointer to an instance of
                    263: ** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
                    264: ** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
                    265: ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
1.3       misho     266: ** and [sqlite3_close_v2()] are its destructors.  There are many other
                    267: ** interfaces (such as
1.2       misho     268: ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
                    269: ** [sqlite3_busy_timeout()] to name but three) that are methods on an
                    270: ** sqlite3 object.
                    271: */
                    272: typedef struct sqlite3 sqlite3;
                    273: 
                    274: /*
                    275: ** CAPI3REF: 64-Bit Integer Types
                    276: ** KEYWORDS: sqlite_int64 sqlite_uint64
                    277: **
                    278: ** Because there is no cross-platform way to specify 64-bit integer types
                    279: ** SQLite includes typedefs for 64-bit signed and unsigned integers.
                    280: **
                    281: ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
                    282: ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
                    283: ** compatibility only.
                    284: **
                    285: ** ^The sqlite3_int64 and sqlite_int64 types can store integer values
                    286: ** between -9223372036854775808 and +9223372036854775807 inclusive.  ^The
1.5       misho     287: ** sqlite3_uint64 and sqlite_uint64 types can store integer values
1.2       misho     288: ** between 0 and +18446744073709551615 inclusive.
                    289: */
                    290: #ifdef SQLITE_INT64_TYPE
                    291:   typedef SQLITE_INT64_TYPE sqlite_int64;
1.5       misho     292: # ifdef SQLITE_UINT64_TYPE
                    293:     typedef SQLITE_UINT64_TYPE sqlite_uint64;
                    294: # else
                    295:     typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
                    296: # endif
1.2       misho     297: #elif defined(_MSC_VER) || defined(__BORLANDC__)
                    298:   typedef __int64 sqlite_int64;
                    299:   typedef unsigned __int64 sqlite_uint64;
                    300: #else
                    301:   typedef long long int sqlite_int64;
                    302:   typedef unsigned long long int sqlite_uint64;
                    303: #endif
                    304: typedef sqlite_int64 sqlite3_int64;
                    305: typedef sqlite_uint64 sqlite3_uint64;
                    306: 
                    307: /*
                    308: ** If compiling for a processor that lacks floating point support,
                    309: ** substitute integer for floating-point.
                    310: */
                    311: #ifdef SQLITE_OMIT_FLOATING_POINT
                    312: # define double sqlite3_int64
                    313: #endif
                    314: 
                    315: /*
                    316: ** CAPI3REF: Closing A Database Connection
1.4       misho     317: ** DESTRUCTOR: sqlite3
1.2       misho     318: **
1.3       misho     319: ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
                    320: ** for the [sqlite3] object.
1.4       misho     321: ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if
1.3       misho     322: ** the [sqlite3] object is successfully destroyed and all associated
                    323: ** resources are deallocated.
                    324: **
1.5       misho     325: ** Ideally, applications should [sqlite3_finalize | finalize] all
                    326: ** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and
                    327: ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
                    328: ** with the [sqlite3] object prior to attempting to close the object.
1.3       misho     329: ** ^If the database connection is associated with unfinalized prepared
1.5       misho     330: ** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then
                    331: ** sqlite3_close() will leave the database connection open and return
                    332: ** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared
                    333: ** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups,
                    334: ** it returns [SQLITE_OK] regardless, but instead of deallocating the database
                    335: ** connection immediately, it marks the database connection as an unusable
                    336: ** "zombie" and makes arrangements to automatically deallocate the database
                    337: ** connection after all prepared statements are finalized, all BLOB handles
                    338: ** are closed, and all backups have finished. The sqlite3_close_v2() interface
                    339: ** is intended for use with host languages that are garbage collected, and
                    340: ** where the order in which destructors are called is arbitrary.
1.2       misho     341: **
1.3       misho     342: ** ^If an [sqlite3] object is destroyed while a transaction is open,
1.2       misho     343: ** the transaction is automatically rolled back.
                    344: **
1.3       misho     345: ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
                    346: ** must be either a NULL
1.2       misho     347: ** pointer or an [sqlite3] object pointer obtained
                    348: ** from [sqlite3_open()], [sqlite3_open16()], or
                    349: ** [sqlite3_open_v2()], and not previously closed.
1.3       misho     350: ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
                    351: ** argument is a harmless no-op.
1.2       misho     352: */
1.3       misho     353: SQLITE_API int sqlite3_close(sqlite3*);
                    354: SQLITE_API int sqlite3_close_v2(sqlite3*);
1.2       misho     355: 
                    356: /*
                    357: ** The type for a callback function.
                    358: ** This is legacy and deprecated.  It is included for historical
                    359: ** compatibility and is not documented.
                    360: */
                    361: typedef int (*sqlite3_callback)(void*,int,char**, char**);
                    362: 
                    363: /*
                    364: ** CAPI3REF: One-Step Query Execution Interface
1.4       misho     365: ** METHOD: sqlite3
1.2       misho     366: **
                    367: ** The sqlite3_exec() interface is a convenience wrapper around
                    368: ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
                    369: ** that allows an application to run multiple statements of SQL
1.5       misho     370: ** without having to use a lot of C code.
1.2       misho     371: **
                    372: ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
                    373: ** semicolon-separate SQL statements passed into its 2nd argument,
                    374: ** in the context of the [database connection] passed in as its 1st
                    375: ** argument.  ^If the callback function of the 3rd argument to
                    376: ** sqlite3_exec() is not NULL, then it is invoked for each result row
                    377: ** coming out of the evaluated SQL statements.  ^The 4th argument to
                    378: ** sqlite3_exec() is relayed through to the 1st argument of each
                    379: ** callback invocation.  ^If the callback pointer to sqlite3_exec()
                    380: ** is NULL, then no callback is ever invoked and result rows are
                    381: ** ignored.
                    382: **
                    383: ** ^If an error occurs while evaluating the SQL statements passed into
                    384: ** sqlite3_exec(), then execution of the current statement stops and
                    385: ** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
                    386: ** is not NULL then any error message is written into memory obtained
                    387: ** from [sqlite3_malloc()] and passed back through the 5th parameter.
                    388: ** To avoid memory leaks, the application should invoke [sqlite3_free()]
                    389: ** on error message strings returned through the 5th parameter of
1.4       misho     390: ** sqlite3_exec() after the error message string is no longer needed.
1.2       misho     391: ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
                    392: ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
                    393: ** NULL before returning.
                    394: **
                    395: ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
                    396: ** routine returns SQLITE_ABORT without invoking the callback again and
                    397: ** without running any subsequent SQL statements.
                    398: **
                    399: ** ^The 2nd argument to the sqlite3_exec() callback function is the
                    400: ** number of columns in the result.  ^The 3rd argument to the sqlite3_exec()
                    401: ** callback is an array of pointers to strings obtained as if from
                    402: ** [sqlite3_column_text()], one for each column.  ^If an element of a
                    403: ** result row is NULL then the corresponding string pointer for the
                    404: ** sqlite3_exec() callback is a NULL pointer.  ^The 4th argument to the
                    405: ** sqlite3_exec() callback is an array of pointers to strings where each
                    406: ** entry represents the name of corresponding result column as obtained
                    407: ** from [sqlite3_column_name()].
                    408: **
                    409: ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
1.5       misho     410: ** to an empty string, or a pointer that contains only whitespace and/or
1.2       misho     411: ** SQL comments, then no SQL statements are evaluated and the database
                    412: ** is not changed.
                    413: **
                    414: ** Restrictions:
                    415: **
                    416: ** <ul>
1.4       misho     417: ** <li> The application must ensure that the 1st parameter to sqlite3_exec()
1.2       misho     418: **      is a valid and open [database connection].
1.4       misho     419: ** <li> The application must not close the [database connection] specified by
1.2       misho     420: **      the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
                    421: ** <li> The application must not modify the SQL statement text passed into
                    422: **      the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
                    423: ** </ul>
                    424: */
                    425: SQLITE_API int sqlite3_exec(
                    426:   sqlite3*,                                  /* An open database */
                    427:   const char *sql,                           /* SQL to be evaluated */
                    428:   int (*callback)(void*,int,char**,char**),  /* Callback function */
                    429:   void *,                                    /* 1st argument to callback */
                    430:   char **errmsg                              /* Error msg written here */
                    431: );
                    432: 
                    433: /*
                    434: ** CAPI3REF: Result Codes
1.4       misho     435: ** KEYWORDS: {result code definitions}
1.2       misho     436: **
                    437: ** Many SQLite functions return an integer result code from the set shown
                    438: ** here in order to indicate success or failure.
                    439: **
                    440: ** New error codes may be added in future versions of SQLite.
                    441: **
1.4       misho     442: ** See also: [extended result code definitions]
1.2       misho     443: */
                    444: #define SQLITE_OK           0   /* Successful result */
                    445: /* beginning-of-error-codes */
1.5       misho     446: #define SQLITE_ERROR        1   /* Generic error */
1.2       misho     447: #define SQLITE_INTERNAL     2   /* Internal logic error in SQLite */
                    448: #define SQLITE_PERM         3   /* Access permission denied */
                    449: #define SQLITE_ABORT        4   /* Callback routine requested an abort */
                    450: #define SQLITE_BUSY         5   /* The database file is locked */
                    451: #define SQLITE_LOCKED       6   /* A table in the database is locked */
                    452: #define SQLITE_NOMEM        7   /* A malloc() failed */
                    453: #define SQLITE_READONLY     8   /* Attempt to write a readonly database */
                    454: #define SQLITE_INTERRUPT    9   /* Operation terminated by sqlite3_interrupt()*/
                    455: #define SQLITE_IOERR       10   /* Some kind of disk I/O error occurred */
                    456: #define SQLITE_CORRUPT     11   /* The database disk image is malformed */
                    457: #define SQLITE_NOTFOUND    12   /* Unknown opcode in sqlite3_file_control() */
                    458: #define SQLITE_FULL        13   /* Insertion failed because database is full */
                    459: #define SQLITE_CANTOPEN    14   /* Unable to open the database file */
                    460: #define SQLITE_PROTOCOL    15   /* Database lock protocol error */
1.5       misho     461: #define SQLITE_EMPTY       16   /* Internal use only */
1.2       misho     462: #define SQLITE_SCHEMA      17   /* The database schema changed */
                    463: #define SQLITE_TOOBIG      18   /* String or BLOB exceeds size limit */
                    464: #define SQLITE_CONSTRAINT  19   /* Abort due to constraint violation */
                    465: #define SQLITE_MISMATCH    20   /* Data type mismatch */
                    466: #define SQLITE_MISUSE      21   /* Library used incorrectly */
                    467: #define SQLITE_NOLFS       22   /* Uses OS features not supported on host */
                    468: #define SQLITE_AUTH        23   /* Authorization denied */
1.5       misho     469: #define SQLITE_FORMAT      24   /* Not used */
1.2       misho     470: #define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
                    471: #define SQLITE_NOTADB      26   /* File opened that is not a database file */
1.4       misho     472: #define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
                    473: #define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
1.2       misho     474: #define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
                    475: #define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
                    476: /* end-of-error-codes */
                    477: 
                    478: /*
                    479: ** CAPI3REF: Extended Result Codes
1.4       misho     480: ** KEYWORDS: {extended result code definitions}
1.2       misho     481: **
1.4       misho     482: ** In its default configuration, SQLite API routines return one of 30 integer
                    483: ** [result codes].  However, experience has shown that many of
1.2       misho     484: ** these result codes are too coarse-grained.  They do not provide as
                    485: ** much information about problems as programmers might like.  In an effort to
1.5       misho     486: ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]
                    487: ** and later) include
1.2       misho     488: ** support for additional result codes that provide more detailed information
1.4       misho     489: ** about errors. These [extended result codes] are enabled or disabled
1.2       misho     490: ** on a per database connection basis using the
1.4       misho     491: ** [sqlite3_extended_result_codes()] API.  Or, the extended code for
                    492: ** the most recent error can be obtained using
                    493: ** [sqlite3_extended_errcode()].
1.2       misho     494: */
1.5       misho     495: #define SQLITE_ERROR_MISSING_COLLSEQ   (SQLITE_ERROR | (1<<8))
                    496: #define SQLITE_ERROR_RETRY             (SQLITE_ERROR | (2<<8))
                    497: #define SQLITE_ERROR_SNAPSHOT          (SQLITE_ERROR | (3<<8))
1.2       misho     498: #define SQLITE_IOERR_READ              (SQLITE_IOERR | (1<<8))
                    499: #define SQLITE_IOERR_SHORT_READ        (SQLITE_IOERR | (2<<8))
                    500: #define SQLITE_IOERR_WRITE             (SQLITE_IOERR | (3<<8))
                    501: #define SQLITE_IOERR_FSYNC             (SQLITE_IOERR | (4<<8))
                    502: #define SQLITE_IOERR_DIR_FSYNC         (SQLITE_IOERR | (5<<8))
                    503: #define SQLITE_IOERR_TRUNCATE          (SQLITE_IOERR | (6<<8))
                    504: #define SQLITE_IOERR_FSTAT             (SQLITE_IOERR | (7<<8))
                    505: #define SQLITE_IOERR_UNLOCK            (SQLITE_IOERR | (8<<8))
                    506: #define SQLITE_IOERR_RDLOCK            (SQLITE_IOERR | (9<<8))
                    507: #define SQLITE_IOERR_DELETE            (SQLITE_IOERR | (10<<8))
                    508: #define SQLITE_IOERR_BLOCKED           (SQLITE_IOERR | (11<<8))
                    509: #define SQLITE_IOERR_NOMEM             (SQLITE_IOERR | (12<<8))
                    510: #define SQLITE_IOERR_ACCESS            (SQLITE_IOERR | (13<<8))
                    511: #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
                    512: #define SQLITE_IOERR_LOCK              (SQLITE_IOERR | (15<<8))
                    513: #define SQLITE_IOERR_CLOSE             (SQLITE_IOERR | (16<<8))
                    514: #define SQLITE_IOERR_DIR_CLOSE         (SQLITE_IOERR | (17<<8))
                    515: #define SQLITE_IOERR_SHMOPEN           (SQLITE_IOERR | (18<<8))
                    516: #define SQLITE_IOERR_SHMSIZE           (SQLITE_IOERR | (19<<8))
                    517: #define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
                    518: #define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
                    519: #define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
1.3       misho     520: #define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
1.4       misho     521: #define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
                    522: #define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
                    523: #define SQLITE_IOERR_CONVPATH          (SQLITE_IOERR | (26<<8))
                    524: #define SQLITE_IOERR_VNODE             (SQLITE_IOERR | (27<<8))
                    525: #define SQLITE_IOERR_AUTH              (SQLITE_IOERR | (28<<8))
1.5       misho     526: #define SQLITE_IOERR_BEGIN_ATOMIC      (SQLITE_IOERR | (29<<8))
                    527: #define SQLITE_IOERR_COMMIT_ATOMIC     (SQLITE_IOERR | (30<<8))
                    528: #define SQLITE_IOERR_ROLLBACK_ATOMIC   (SQLITE_IOERR | (31<<8))
                    529: #define SQLITE_IOERR_DATA              (SQLITE_IOERR | (32<<8))
1.6       misho     530: #define SQLITE_IOERR_CORRUPTFS         (SQLITE_IOERR | (33<<8))
1.6.2.1 ! misho     531: #define SQLITE_IOERR_IN_PAGE           (SQLITE_IOERR | (34<<8))
1.2       misho     532: #define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
1.5       misho     533: #define SQLITE_LOCKED_VTAB             (SQLITE_LOCKED |  (2<<8))
1.2       misho     534: #define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
1.4       misho     535: #define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
1.5       misho     536: #define SQLITE_BUSY_TIMEOUT            (SQLITE_BUSY   |  (3<<8))
1.2       misho     537: #define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
1.3       misho     538: #define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
                    539: #define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
1.4       misho     540: #define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))
1.5       misho     541: #define SQLITE_CANTOPEN_DIRTYWAL       (SQLITE_CANTOPEN | (5<<8)) /* Not Used */
                    542: #define SQLITE_CANTOPEN_SYMLINK        (SQLITE_CANTOPEN | (6<<8))
1.2       misho     543: #define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
1.5       misho     544: #define SQLITE_CORRUPT_SEQUENCE        (SQLITE_CORRUPT | (2<<8))
                    545: #define SQLITE_CORRUPT_INDEX           (SQLITE_CORRUPT | (3<<8))
1.2       misho     546: #define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
                    547: #define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
1.4       misho     548: #define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
                    549: #define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
1.5       misho     550: #define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
                    551: #define SQLITE_READONLY_DIRECTORY      (SQLITE_READONLY | (6<<8))
1.3       misho     552: #define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
1.4       misho     553: #define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
                    554: #define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
                    555: #define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
                    556: #define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
                    557: #define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
                    558: #define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
                    559: #define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
                    560: #define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
                    561: #define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
                    562: #define SQLITE_CONSTRAINT_ROWID        (SQLITE_CONSTRAINT |(10<<8))
1.5       misho     563: #define SQLITE_CONSTRAINT_PINNED       (SQLITE_CONSTRAINT |(11<<8))
1.6.2.1 ! misho     564: #define SQLITE_CONSTRAINT_DATATYPE     (SQLITE_CONSTRAINT |(12<<8))
1.4       misho     565: #define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
                    566: #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
1.6.2.1 ! misho     567: #define SQLITE_NOTICE_RBU              (SQLITE_NOTICE | (3<<8))
1.4       misho     568: #define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
                    569: #define SQLITE_AUTH_USER               (SQLITE_AUTH | (1<<8))
                    570: #define SQLITE_OK_LOAD_PERMANENTLY     (SQLITE_OK | (1<<8))
1.6.2.1 ! misho     571: #define SQLITE_OK_SYMLINK              (SQLITE_OK | (2<<8)) /* internal use only */
1.2       misho     572: 
                    573: /*
                    574: ** CAPI3REF: Flags For File Open Operations
                    575: **
                    576: ** These bit values are intended for use in the
                    577: ** 3rd parameter to the [sqlite3_open_v2()] interface and
                    578: ** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
1.6.2.1 ! misho     579: **
        !           580: ** Only those flags marked as "Ok for sqlite3_open_v2()" may be
        !           581: ** used as the third argument to the [sqlite3_open_v2()] interface.
        !           582: ** The other flags have historically been ignored by sqlite3_open_v2(),
        !           583: ** though future versions of SQLite might change so that an error is
        !           584: ** raised if any of the disallowed bits are passed into sqlite3_open_v2().
        !           585: ** Applications should not depend on the historical behavior.
        !           586: **
        !           587: ** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into
        !           588: ** [sqlite3_open_v2()] does *not* cause the underlying database file
        !           589: ** to be opened using O_EXCL.  Passing SQLITE_OPEN_EXCLUSIVE into
        !           590: ** [sqlite3_open_v2()] has historically be a no-op and might become an
        !           591: ** error in future versions of SQLite.
1.2       misho     592: */
                    593: #define SQLITE_OPEN_READONLY         0x00000001  /* Ok for sqlite3_open_v2() */
                    594: #define SQLITE_OPEN_READWRITE        0x00000002  /* Ok for sqlite3_open_v2() */
                    595: #define SQLITE_OPEN_CREATE           0x00000004  /* Ok for sqlite3_open_v2() */
                    596: #define SQLITE_OPEN_DELETEONCLOSE    0x00000008  /* VFS only */
                    597: #define SQLITE_OPEN_EXCLUSIVE        0x00000010  /* VFS only */
                    598: #define SQLITE_OPEN_AUTOPROXY        0x00000020  /* VFS only */
                    599: #define SQLITE_OPEN_URI              0x00000040  /* Ok for sqlite3_open_v2() */
1.3       misho     600: #define SQLITE_OPEN_MEMORY           0x00000080  /* Ok for sqlite3_open_v2() */
1.2       misho     601: #define SQLITE_OPEN_MAIN_DB          0x00000100  /* VFS only */
                    602: #define SQLITE_OPEN_TEMP_DB          0x00000200  /* VFS only */
                    603: #define SQLITE_OPEN_TRANSIENT_DB     0x00000400  /* VFS only */
                    604: #define SQLITE_OPEN_MAIN_JOURNAL     0x00000800  /* VFS only */
                    605: #define SQLITE_OPEN_TEMP_JOURNAL     0x00001000  /* VFS only */
                    606: #define SQLITE_OPEN_SUBJOURNAL       0x00002000  /* VFS only */
1.5       misho     607: #define SQLITE_OPEN_SUPER_JOURNAL    0x00004000  /* VFS only */
1.2       misho     608: #define SQLITE_OPEN_NOMUTEX          0x00008000  /* Ok for sqlite3_open_v2() */
                    609: #define SQLITE_OPEN_FULLMUTEX        0x00010000  /* Ok for sqlite3_open_v2() */
                    610: #define SQLITE_OPEN_SHAREDCACHE      0x00020000  /* Ok for sqlite3_open_v2() */
                    611: #define SQLITE_OPEN_PRIVATECACHE     0x00040000  /* Ok for sqlite3_open_v2() */
                    612: #define SQLITE_OPEN_WAL              0x00080000  /* VFS only */
1.5       misho     613: #define SQLITE_OPEN_NOFOLLOW         0x01000000  /* Ok for sqlite3_open_v2() */
1.6.2.1 ! misho     614: #define SQLITE_OPEN_EXRESCODE        0x02000000  /* Extended result codes */
1.2       misho     615: 
                    616: /* Reserved:                         0x00F00000 */
1.5       misho     617: /* Legacy compatibility: */
                    618: #define SQLITE_OPEN_MASTER_JOURNAL   0x00004000  /* VFS only */
                    619: 
1.2       misho     620: 
                    621: /*
                    622: ** CAPI3REF: Device Characteristics
                    623: **
                    624: ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
1.3       misho     625: ** object returns an integer which is a vector of these
1.2       misho     626: ** bit values expressing I/O characteristics of the mass storage
                    627: ** device that holds the file that the [sqlite3_io_methods]
                    628: ** refers to.
                    629: **
                    630: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
                    631: ** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
                    632: ** mean that writes of blocks that are nnn bytes in size and
                    633: ** are aligned to an address which is an integer multiple of
                    634: ** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
                    635: ** that when data is appended to a file, the data is appended
                    636: ** first then the size of the file is extended, never the other
                    637: ** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
                    638: ** information is written to disk in the same order as calls
                    639: ** to xWrite().  The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
                    640: ** after reboot following a crash or power loss, the only bytes in a
                    641: ** file that were written at the application level might have changed
                    642: ** and that adjacent bytes, even bytes within the same sector are
1.4       misho     643: ** guaranteed to be unchanged.  The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
1.5       misho     644: ** flag indicates that a file cannot be deleted when open.  The
1.4       misho     645: ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on
                    646: ** read-only media and cannot be changed even by processes with
                    647: ** elevated privileges.
1.5       misho     648: **
                    649: ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying
                    650: ** filesystem supports doing multiple write operations atomically when those
                    651: ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and
                    652: ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].
1.2       misho     653: */
                    654: #define SQLITE_IOCAP_ATOMIC                 0x00000001
                    655: #define SQLITE_IOCAP_ATOMIC512              0x00000002
                    656: #define SQLITE_IOCAP_ATOMIC1K               0x00000004
                    657: #define SQLITE_IOCAP_ATOMIC2K               0x00000008
                    658: #define SQLITE_IOCAP_ATOMIC4K               0x00000010
                    659: #define SQLITE_IOCAP_ATOMIC8K               0x00000020
                    660: #define SQLITE_IOCAP_ATOMIC16K              0x00000040
                    661: #define SQLITE_IOCAP_ATOMIC32K              0x00000080
                    662: #define SQLITE_IOCAP_ATOMIC64K              0x00000100
                    663: #define SQLITE_IOCAP_SAFE_APPEND            0x00000200
                    664: #define SQLITE_IOCAP_SEQUENTIAL             0x00000400
                    665: #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN  0x00000800
                    666: #define SQLITE_IOCAP_POWERSAFE_OVERWRITE    0x00001000
1.4       misho     667: #define SQLITE_IOCAP_IMMUTABLE              0x00002000
1.5       misho     668: #define SQLITE_IOCAP_BATCH_ATOMIC           0x00004000
1.2       misho     669: 
                    670: /*
                    671: ** CAPI3REF: File Locking Levels
                    672: **
                    673: ** SQLite uses one of these integer values as the second
                    674: ** argument to calls it makes to the xLock() and xUnlock() methods
1.6.2.1 ! misho     675: ** of an [sqlite3_io_methods] object.  These values are ordered from
        !           676: ** lest restrictive to most restrictive.
        !           677: **
        !           678: ** The argument to xLock() is always SHARED or higher.  The argument to
        !           679: ** xUnlock is either SHARED or NONE.
1.2       misho     680: */
1.6.2.1 ! misho     681: #define SQLITE_LOCK_NONE          0       /* xUnlock() only */
        !           682: #define SQLITE_LOCK_SHARED        1       /* xLock() or xUnlock() */
        !           683: #define SQLITE_LOCK_RESERVED      2       /* xLock() only */
        !           684: #define SQLITE_LOCK_PENDING       3       /* xLock() only */
        !           685: #define SQLITE_LOCK_EXCLUSIVE     4       /* xLock() only */
1.2       misho     686: 
                    687: /*
                    688: ** CAPI3REF: Synchronization Type Flags
                    689: **
                    690: ** When SQLite invokes the xSync() method of an
                    691: ** [sqlite3_io_methods] object it uses a combination of
                    692: ** these integer values as the second argument.
                    693: **
                    694: ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
                    695: ** sync operation only needs to flush data to mass storage.  Inode
                    696: ** information need not be flushed. If the lower four bits of the flag
                    697: ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
                    698: ** If the lower four bits equal SQLITE_SYNC_FULL, that means
                    699: ** to use Mac OS X style fullsync instead of fsync().
                    700: **
                    701: ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
                    702: ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
                    703: ** settings.  The [synchronous pragma] determines when calls to the
                    704: ** xSync VFS method occur and applies uniformly across all platforms.
                    705: ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
                    706: ** energetic or rigorous or forceful the sync operations are and
                    707: ** only make a difference on Mac OSX for the default SQLite code.
                    708: ** (Third-party VFS implementations might also make the distinction
                    709: ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
                    710: ** operating systems natively supported by SQLite, only Mac OSX
                    711: ** cares about the difference.)
                    712: */
                    713: #define SQLITE_SYNC_NORMAL        0x00002
                    714: #define SQLITE_SYNC_FULL          0x00003
                    715: #define SQLITE_SYNC_DATAONLY      0x00010
                    716: 
                    717: /*
                    718: ** CAPI3REF: OS Interface Open File Handle
                    719: **
1.5       misho     720: ** An [sqlite3_file] object represents an open file in the
1.2       misho     721: ** [sqlite3_vfs | OS interface layer].  Individual OS interface
                    722: ** implementations will
                    723: ** want to subclass this object by appending additional fields
                    724: ** for their own use.  The pMethods entry is a pointer to an
                    725: ** [sqlite3_io_methods] object that defines methods for performing
                    726: ** I/O operations on the open file.
                    727: */
                    728: typedef struct sqlite3_file sqlite3_file;
                    729: struct sqlite3_file {
                    730:   const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
                    731: };
                    732: 
                    733: /*
                    734: ** CAPI3REF: OS Interface File Virtual Methods Object
                    735: **
                    736: ** Every file opened by the [sqlite3_vfs.xOpen] method populates an
                    737: ** [sqlite3_file] object (or, more commonly, a subclass of the
                    738: ** [sqlite3_file] object) with a pointer to an instance of this object.
                    739: ** This object defines the methods used to perform various operations
                    740: ** against the open file represented by the [sqlite3_file] object.
                    741: **
1.5       misho     742: ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
1.2       misho     743: ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
                    744: ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed.  The
                    745: ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
                    746: ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
                    747: ** to NULL.
                    748: **
                    749: ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
                    750: ** [SQLITE_SYNC_FULL].  The first choice is the normal fsync().
                    751: ** The second choice is a Mac OS X style fullsync.  The [SQLITE_SYNC_DATAONLY]
                    752: ** flag may be ORed in to indicate that only the data of the file
                    753: ** and not its inode needs to be synced.
                    754: **
                    755: ** The integer values to xLock() and xUnlock() are one of
                    756: ** <ul>
                    757: ** <li> [SQLITE_LOCK_NONE],
                    758: ** <li> [SQLITE_LOCK_SHARED],
                    759: ** <li> [SQLITE_LOCK_RESERVED],
                    760: ** <li> [SQLITE_LOCK_PENDING], or
                    761: ** <li> [SQLITE_LOCK_EXCLUSIVE].
                    762: ** </ul>
1.6.2.1 ! misho     763: ** xLock() upgrades the database file lock.  In other words, xLock() moves the
        !           764: ** database file lock in the direction NONE toward EXCLUSIVE. The argument to
        !           765: ** xLock() is always on of SHARED, RESERVED, PENDING, or EXCLUSIVE, never
        !           766: ** SQLITE_LOCK_NONE.  If the database file lock is already at or above the
        !           767: ** requested lock, then the call to xLock() is a no-op.
        !           768: ** xUnlock() downgrades the database file lock to either SHARED or NONE.
        !           769: *  If the lock is already at or below the requested lock state, then the call
        !           770: ** to xUnlock() is a no-op.
1.2       misho     771: ** The xCheckReservedLock() method checks whether any database connection,
                    772: ** either in this process or in some other process, is holding a RESERVED,
                    773: ** PENDING, or EXCLUSIVE lock on the file.  It returns true
                    774: ** if such a lock exists and false otherwise.
                    775: **
                    776: ** The xFileControl() method is a generic interface that allows custom
                    777: ** VFS implementations to directly control an open file using the
                    778: ** [sqlite3_file_control()] interface.  The second "op" argument is an
                    779: ** integer opcode.  The third argument is a generic pointer intended to
                    780: ** point to a structure that may contain arguments or space in which to
                    781: ** write return values.  Potential uses for xFileControl() might be
                    782: ** functions to enable blocking locks with timeouts, to change the
                    783: ** locking strategy (for example to use dot-file locks), to inquire
                    784: ** about the status of a lock, or to break stale locks.  The SQLite
                    785: ** core reserves all opcodes less than 100 for its own use.
1.4       misho     786: ** A [file control opcodes | list of opcodes] less than 100 is available.
1.2       misho     787: ** Applications that define a custom xFileControl method should use opcodes
                    788: ** greater than 100 to avoid conflicts.  VFS implementations should
                    789: ** return [SQLITE_NOTFOUND] for file control opcodes that they do not
                    790: ** recognize.
                    791: **
                    792: ** The xSectorSize() method returns the sector size of the
                    793: ** device that underlies the file.  The sector size is the
                    794: ** minimum write that can be performed without disturbing
                    795: ** other bytes in the file.  The xDeviceCharacteristics()
                    796: ** method returns a bit vector describing behaviors of the
                    797: ** underlying device:
                    798: **
                    799: ** <ul>
                    800: ** <li> [SQLITE_IOCAP_ATOMIC]
                    801: ** <li> [SQLITE_IOCAP_ATOMIC512]
                    802: ** <li> [SQLITE_IOCAP_ATOMIC1K]
                    803: ** <li> [SQLITE_IOCAP_ATOMIC2K]
                    804: ** <li> [SQLITE_IOCAP_ATOMIC4K]
                    805: ** <li> [SQLITE_IOCAP_ATOMIC8K]
                    806: ** <li> [SQLITE_IOCAP_ATOMIC16K]
                    807: ** <li> [SQLITE_IOCAP_ATOMIC32K]
                    808: ** <li> [SQLITE_IOCAP_ATOMIC64K]
                    809: ** <li> [SQLITE_IOCAP_SAFE_APPEND]
                    810: ** <li> [SQLITE_IOCAP_SEQUENTIAL]
1.5       misho     811: ** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN]
                    812: ** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE]
                    813: ** <li> [SQLITE_IOCAP_IMMUTABLE]
                    814: ** <li> [SQLITE_IOCAP_BATCH_ATOMIC]
1.2       misho     815: ** </ul>
                    816: **
                    817: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
                    818: ** any size are atomic.  The SQLITE_IOCAP_ATOMICnnn values
                    819: ** mean that writes of blocks that are nnn bytes in size and
                    820: ** are aligned to an address which is an integer multiple of
                    821: ** nnn are atomic.  The SQLITE_IOCAP_SAFE_APPEND value means
                    822: ** that when data is appended to a file, the data is appended
                    823: ** first then the size of the file is extended, never the other
                    824: ** way around.  The SQLITE_IOCAP_SEQUENTIAL property means that
                    825: ** information is written to disk in the same order as calls
                    826: ** to xWrite().
                    827: **
                    828: ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
                    829: ** in the unread portions of the buffer with zeros.  A VFS that
                    830: ** fails to zero-fill short reads might seem to work.  However,
                    831: ** failure to zero-fill short reads will eventually lead to
                    832: ** database corruption.
                    833: */
                    834: typedef struct sqlite3_io_methods sqlite3_io_methods;
                    835: struct sqlite3_io_methods {
                    836:   int iVersion;
                    837:   int (*xClose)(sqlite3_file*);
                    838:   int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
                    839:   int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
                    840:   int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
                    841:   int (*xSync)(sqlite3_file*, int flags);
                    842:   int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
                    843:   int (*xLock)(sqlite3_file*, int);
                    844:   int (*xUnlock)(sqlite3_file*, int);
                    845:   int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
                    846:   int (*xFileControl)(sqlite3_file*, int op, void *pArg);
                    847:   int (*xSectorSize)(sqlite3_file*);
                    848:   int (*xDeviceCharacteristics)(sqlite3_file*);
                    849:   /* Methods above are valid for version 1 */
                    850:   int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
                    851:   int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
                    852:   void (*xShmBarrier)(sqlite3_file*);
                    853:   int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
                    854:   /* Methods above are valid for version 2 */
1.4       misho     855:   int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
                    856:   int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
                    857:   /* Methods above are valid for version 3 */
1.2       misho     858:   /* Additional methods may be added in future releases */
                    859: };
                    860: 
                    861: /*
                    862: ** CAPI3REF: Standard File Control Opcodes
1.4       misho     863: ** KEYWORDS: {file control opcodes} {file control opcode}
1.2       misho     864: **
                    865: ** These integer constants are opcodes for the xFileControl method
                    866: ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
                    867: ** interface.
                    868: **
1.4       misho     869: ** <ul>
                    870: ** <li>[[SQLITE_FCNTL_LOCKSTATE]]
1.2       misho     871: ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
                    872: ** opcode causes the xFileControl method to write the current state of
                    873: ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
                    874: ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
1.6.2.1 ! misho     875: ** into an integer that the pArg argument points to.
        !           876: ** This capability is only available if SQLite is compiled with [SQLITE_DEBUG].
1.4       misho     877: **
1.3       misho     878: ** <li>[[SQLITE_FCNTL_SIZE_HINT]]
1.2       misho     879: ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
                    880: ** layer a hint of how large the database file will grow to be during the
                    881: ** current transaction.  This hint is not guaranteed to be accurate but it
                    882: ** is often close.  The underlying VFS might choose to preallocate database
                    883: ** file space based on this hint in order to help writes to the database
                    884: ** file run faster.
                    885: **
1.5       misho     886: ** <li>[[SQLITE_FCNTL_SIZE_LIMIT]]
                    887: ** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that
                    888: ** implements [sqlite3_deserialize()] to set an upper bound on the size
                    889: ** of the in-memory database.  The argument is a pointer to a [sqlite3_int64].
                    890: ** If the integer pointed to is negative, then it is filled in with the
                    891: ** current limit.  Otherwise the limit is set to the larger of the value
                    892: ** of the integer pointed to and the current database size.  The integer
                    893: ** pointed to is set to the new limit.
                    894: **
1.3       misho     895: ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]
1.2       misho     896: ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
                    897: ** extends and truncates the database file in chunks of a size specified
1.5       misho     898: ** by the user. The fourth argument to [sqlite3_file_control()] should
1.2       misho     899: ** point to an integer (type int) containing the new chunk-size to use
                    900: ** for the nominated database. Allocating database file space in large
                    901: ** chunks (say 1MB at a time), may reduce file-system fragmentation and
                    902: ** improve performance on some systems.
                    903: **
1.3       misho     904: ** <li>[[SQLITE_FCNTL_FILE_POINTER]]
1.2       misho     905: ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
                    906: ** to the [sqlite3_file] object associated with a particular database
1.4       misho     907: ** connection.  See also [SQLITE_FCNTL_JOURNAL_POINTER].
                    908: **
                    909: ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]
                    910: ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer
                    911: ** to the [sqlite3_file] object associated with the journal file (either
                    912: ** the [rollback journal] or the [write-ahead log]) for a particular database
                    913: ** connection.  See also [SQLITE_FCNTL_FILE_POINTER].
1.2       misho     914: **
1.3       misho     915: ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]
1.4       misho     916: ** No longer in use.
                    917: **
                    918: ** <li>[[SQLITE_FCNTL_SYNC]]
                    919: ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and
                    920: ** sent to the VFS immediately before the xSync method is invoked on a
1.5       misho     921: ** database file descriptor. Or, if the xSync method is not invoked
                    922: ** because the user has configured SQLite with
                    923: ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place
1.4       misho     924: ** of the xSync method. In most cases, the pointer argument passed with
                    925: ** this file-control is NULL. However, if the database file is being synced
                    926: ** as part of a multi-database commit, the argument points to a nul-terminated
1.5       misho     927: ** string containing the transactions super-journal file name. VFSes that
                    928: ** do not need this signal should silently ignore this opcode. Applications
                    929: ** should not call [sqlite3_file_control()] with this opcode as doing so may
                    930: ** disrupt the operation of the specialized VFSes that do require it.
1.4       misho     931: **
                    932: ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]
                    933: ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite
                    934: ** and sent to the VFS after a transaction has been committed immediately
                    935: ** but before the database is unlocked. VFSes that do not need this signal
                    936: ** should silently ignore this opcode. Applications should not call
1.5       misho     937: ** [sqlite3_file_control()] with this opcode as doing so may disrupt the
                    938: ** operation of the specialized VFSes that do require it.
1.2       misho     939: **
1.3       misho     940: ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]
1.2       misho     941: ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
                    942: ** retry counts and intervals for certain disk I/O operations for the
                    943: ** windows [VFS] in order to provide robustness in the presence of
                    944: ** anti-virus programs.  By default, the windows VFS will retry file read,
                    945: ** file write, and file delete operations up to 10 times, with a delay
                    946: ** of 25 milliseconds before the first retry and with the delay increasing
                    947: ** by an additional 25 milliseconds with each subsequent retry.  This
                    948: ** opcode allows these two values (10 retries and 25 milliseconds of delay)
                    949: ** to be adjusted.  The values are changed for all database connections
                    950: ** within the same process.  The argument is a pointer to an array of two
1.5       misho     951: ** integers where the first integer is the new retry count and the second
1.2       misho     952: ** integer is the delay.  If either integer is negative, then the setting
                    953: ** is not changed but instead the prior value of that setting is written
                    954: ** into the array entry, allowing the current retry settings to be
                    955: ** interrogated.  The zDbName parameter is ignored.
                    956: **
1.3       misho     957: ** <li>[[SQLITE_FCNTL_PERSIST_WAL]]
1.2       misho     958: ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
1.3       misho     959: ** persistent [WAL | Write Ahead Log] setting.  By default, the auxiliary
1.5       misho     960: ** write ahead log ([WAL file]) and shared memory
                    961: ** files used for transaction control
1.2       misho     962: ** are automatically deleted when the latest connection to the database
                    963: ** closes.  Setting persistent WAL mode causes those files to persist after
                    964: ** close.  Persisting the files is useful when other processes that do not
                    965: ** have write permission on the directory containing the database file want
                    966: ** to read the database file, as the WAL and shared memory files must exist
                    967: ** in order for the database to be readable.  The fourth parameter to
                    968: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
                    969: ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
                    970: ** WAL mode.  If the integer is -1, then it is overwritten with the current
                    971: ** WAL persistence setting.
                    972: **
1.3       misho     973: ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]
1.2       misho     974: ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
                    975: ** persistent "powersafe-overwrite" or "PSOW" setting.  The PSOW setting
                    976: ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
                    977: ** xDeviceCharacteristics methods. The fourth parameter to
                    978: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
                    979: ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
                    980: ** mode.  If the integer is -1, then it is overwritten with the current
                    981: ** zero-damage mode setting.
                    982: **
1.3       misho     983: ** <li>[[SQLITE_FCNTL_OVERWRITE]]
1.2       misho     984: ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
                    985: ** a write transaction to indicate that, unless it is rolled back for some
1.5       misho     986: ** reason, the entire database file will be overwritten by the current
1.2       misho     987: ** transaction. This is used by VACUUM operations.
                    988: **
1.3       misho     989: ** <li>[[SQLITE_FCNTL_VFSNAME]]
1.2       misho     990: ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
                    991: ** all [VFSes] in the VFS stack.  The names are of all VFS shims and the
1.5       misho     992: ** final bottom-level VFS are written into memory obtained from
1.2       misho     993: ** [sqlite3_malloc()] and the result is stored in the char* variable
                    994: ** that the fourth parameter of [sqlite3_file_control()] points to.
                    995: ** The caller is responsible for freeing the memory when done.  As with
                    996: ** all file-control actions, there is no guarantee that this will actually
                    997: ** do anything.  Callers should initialize the char* variable to a NULL
                    998: ** pointer in case this file-control is not implemented.  This file-control
                    999: ** is intended for diagnostic use only.
1.3       misho    1000: **
1.4       misho    1001: ** <li>[[SQLITE_FCNTL_VFS_POINTER]]
                   1002: ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level
                   1003: ** [VFSes] currently in use.  ^(The argument X in
                   1004: ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be
                   1005: ** of type "[sqlite3_vfs] **".  This opcodes will set *X
                   1006: ** to a pointer to the top-level VFS.)^
                   1007: ** ^When there are multiple VFS shims in the stack, this opcode finds the
                   1008: ** upper-most shim only.
                   1009: **
1.3       misho    1010: ** <li>[[SQLITE_FCNTL_PRAGMA]]
1.5       misho    1011: ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA]
1.3       misho    1012: ** file control is sent to the open [sqlite3_file] object corresponding
                   1013: ** to the database file to which the pragma statement refers. ^The argument
                   1014: ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of
                   1015: ** pointers to strings (char**) in which the second element of the array
                   1016: ** is the name of the pragma and the third element is the argument to the
                   1017: ** pragma or NULL if the pragma has no argument.  ^The handler for an
                   1018: ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element
                   1019: ** of the char** argument point to a string obtained from [sqlite3_mprintf()]
                   1020: ** or the equivalent and that string will become the result of the pragma or
                   1021: ** the error message if the pragma fails. ^If the
1.5       misho    1022: ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal
1.3       misho    1023: ** [PRAGMA] processing continues.  ^If the [SQLITE_FCNTL_PRAGMA]
                   1024: ** file control returns [SQLITE_OK], then the parser assumes that the
                   1025: ** VFS has handled the PRAGMA itself and the parser generates a no-op
1.4       misho    1026: ** prepared statement if result string is NULL, or that returns a copy
                   1027: ** of the result string if the string is non-NULL.
                   1028: ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns
1.3       misho    1029: ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means
                   1030: ** that the VFS encountered an error while handling the [PRAGMA] and the
                   1031: ** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
                   1032: ** file control occurs at the beginning of pragma statement analysis and so
                   1033: ** it is able to override built-in [PRAGMA] statements.
                   1034: **
                   1035: ** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
1.4       misho    1036: ** ^The [SQLITE_FCNTL_BUSYHANDLER]
                   1037: ** file-control may be invoked by SQLite on the database file handle
1.3       misho    1038: ** shortly after it is opened in order to provide a custom VFS with access
1.5       misho    1039: ** to the connection's busy-handler callback. The argument is of type (void**)
1.3       misho    1040: ** - an array of two (void *) values. The first (void *) actually points
1.5       misho    1041: ** to a function of type (int (*)(void *)). In order to invoke the connection's
1.3       misho    1042: ** busy-handler, this function should be invoked with the second (void *) in
                   1043: ** the array as the only argument. If it returns non-zero, then the operation
                   1044: ** should be retried. If it returns zero, the custom VFS should abandon the
                   1045: ** current operation.
                   1046: **
                   1047: ** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
1.5       misho    1048: ** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
1.4       misho    1049: ** to have SQLite generate a
1.3       misho    1050: ** temporary filename using the same algorithm that is followed to generate
                   1051: ** temporary filenames for TEMP tables and other internal uses.  The
                   1052: ** argument should be a char** which will be filled with the filename
                   1053: ** written into memory obtained from [sqlite3_malloc()].  The caller should
                   1054: ** invoke [sqlite3_free()] on the result to avoid a memory leak.
                   1055: **
1.4       misho    1056: ** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
                   1057: ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
                   1058: ** maximum number of bytes that will be used for memory-mapped I/O.
                   1059: ** The argument is a pointer to a value of type sqlite3_int64 that
                   1060: ** is an advisory maximum number of bytes in the file to memory map.  The
                   1061: ** pointer is overwritten with the old value.  The limit is not changed if
1.5       misho    1062: ** the value originally pointed to is negative, and so the current limit
1.4       misho    1063: ** can be queried by passing in a pointer to a negative number.  This
                   1064: ** file-control is used internally to implement [PRAGMA mmap_size].
                   1065: **
                   1066: ** <li>[[SQLITE_FCNTL_TRACE]]
                   1067: ** The [SQLITE_FCNTL_TRACE] file control provides advisory information
                   1068: ** to the VFS about what the higher layers of the SQLite stack are doing.
                   1069: ** This file control is used by some VFS activity tracing [shims].
                   1070: ** The argument is a zero-terminated string.  Higher layers in the
                   1071: ** SQLite stack may generate instances of this file control if
                   1072: ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.
                   1073: **
                   1074: ** <li>[[SQLITE_FCNTL_HAS_MOVED]]
                   1075: ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a
                   1076: ** pointer to an integer and it writes a boolean into that integer depending
                   1077: ** on whether or not the file has been renamed, moved, or deleted since it
                   1078: ** was first opened.
                   1079: **
1.5       misho    1080: ** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]
                   1081: ** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the
                   1082: ** underlying native file handle associated with a file handle.  This file
                   1083: ** control interprets its argument as a pointer to a native file handle and
                   1084: ** writes the resulting value there.
                   1085: **
1.4       misho    1086: ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]
                   1087: ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging.  This
                   1088: ** opcode causes the xFileControl method to swap the file handle with the one
                   1089: ** pointed to by the pArg argument.  This capability is used during testing
                   1090: ** and only needs to be supported when SQLITE_TEST is defined.
                   1091: **
                   1092: ** <li>[[SQLITE_FCNTL_WAL_BLOCK]]
                   1093: ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might
                   1094: ** be advantageous to block on the next WAL lock if the lock is not immediately
                   1095: ** available.  The WAL subsystem issues this signal during rare
                   1096: ** circumstances in order to fix a problem with priority inversion.
                   1097: ** Applications should <em>not</em> use this file-control.
                   1098: **
                   1099: ** <li>[[SQLITE_FCNTL_ZIPVFS]]
                   1100: ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other
                   1101: ** VFS should return SQLITE_NOTFOUND for this opcode.
                   1102: **
                   1103: ** <li>[[SQLITE_FCNTL_RBU]]
                   1104: ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by
                   1105: ** the RBU extension only.  All other VFS should return SQLITE_NOTFOUND for
1.5       misho    1106: ** this opcode.
                   1107: **
                   1108: ** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]]
                   1109: ** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then
                   1110: ** the file descriptor is placed in "batch write mode", which
                   1111: ** means all subsequent write operations will be deferred and done
                   1112: ** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE].  Systems
                   1113: ** that do not support batch atomic writes will return SQLITE_NOTFOUND.
                   1114: ** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to
                   1115: ** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or
                   1116: ** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make
                   1117: ** no VFS interface calls on the same [sqlite3_file] file descriptor
                   1118: ** except for calls to the xWrite method and the xFileControl method
                   1119: ** with [SQLITE_FCNTL_SIZE_HINT].
                   1120: **
                   1121: ** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]]
                   1122: ** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write
                   1123: ** operations since the previous successful call to
                   1124: ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically.
                   1125: ** This file control returns [SQLITE_OK] if and only if the writes were
                   1126: ** all performed successfully and have been committed to persistent storage.
                   1127: ** ^Regardless of whether or not it is successful, this file control takes
                   1128: ** the file descriptor out of batch write mode so that all subsequent
                   1129: ** write operations are independent.
                   1130: ** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without
                   1131: ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
                   1132: **
                   1133: ** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]]
                   1134: ** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write
                   1135: ** operations since the previous successful call to
                   1136: ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back.
                   1137: ** ^This file control takes the file descriptor out of batch write mode
                   1138: ** so that all subsequent write operations are independent.
                   1139: ** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without
                   1140: ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE].
                   1141: **
                   1142: ** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]]
                   1143: ** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS
                   1144: ** to block for up to M milliseconds before failing when attempting to
                   1145: ** obtain a file lock using the xLock or xShmLock methods of the VFS.
                   1146: ** The parameter is a pointer to a 32-bit signed integer that contains
                   1147: ** the value that M is to be set to. Before returning, the 32-bit signed
                   1148: ** integer is overwritten with the previous value of M.
                   1149: **
                   1150: ** <li>[[SQLITE_FCNTL_DATA_VERSION]]
                   1151: ** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to
                   1152: ** a database file.  The argument is a pointer to a 32-bit unsigned integer.
                   1153: ** The "data version" for the pager is written into the pointer.  The
                   1154: ** "data version" changes whenever any change occurs to the corresponding
                   1155: ** database file, either through SQL statements on the same database
                   1156: ** connection or through transactions committed by separate database
                   1157: ** connections possibly in other processes. The [sqlite3_total_changes()]
                   1158: ** interface can be used to find if any database on the connection has changed,
                   1159: ** but that interface responds to changes on TEMP as well as MAIN and does
                   1160: ** not provide a mechanism to detect changes to MAIN only.  Also, the
                   1161: ** [sqlite3_total_changes()] interface responds to internal changes only and
                   1162: ** omits changes made by other database connections.  The
                   1163: ** [PRAGMA data_version] command provides a mechanism to detect changes to
                   1164: ** a single attached database that occur due to other database connections,
                   1165: ** but omits changes implemented by the database connection on which it is
                   1166: ** called.  This file control is the only mechanism to detect changes that
                   1167: ** happen either internally or externally and that are associated with
                   1168: ** a particular attached database.
                   1169: **
                   1170: ** <li>[[SQLITE_FCNTL_CKPT_START]]
                   1171: ** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint
                   1172: ** in wal mode before the client starts to copy pages from the wal
                   1173: ** file to the database file.
                   1174: **
                   1175: ** <li>[[SQLITE_FCNTL_CKPT_DONE]]
                   1176: ** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint
                   1177: ** in wal mode after the client has finished copying pages from the wal
                   1178: ** file to the database file, but before the *-shm file is updated to
                   1179: ** record the fact that the pages have been checkpointed.
1.6.2.1 ! misho    1180: **
        !          1181: ** <li>[[SQLITE_FCNTL_EXTERNAL_READER]]
        !          1182: ** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect
        !          1183: ** whether or not there is a database client in another process with a wal-mode
        !          1184: ** transaction open on the database or not. It is only available on unix.The
        !          1185: ** (void*) argument passed with this file-control should be a pointer to a
        !          1186: ** value of type (int). The integer value is set to 1 if the database is a wal
        !          1187: ** mode database and there exists at least one client in another process that
        !          1188: ** currently has an SQL transaction open on the database. It is set to 0 if
        !          1189: ** the database is not a wal-mode db, or if there is no such connection in any
        !          1190: ** other process. This opcode cannot be used to detect transactions opened
        !          1191: ** by clients within the current process, only within other processes.
        !          1192: **
        !          1193: ** <li>[[SQLITE_FCNTL_CKSM_FILE]]
        !          1194: ** The [SQLITE_FCNTL_CKSM_FILE] opcode is for use internally by the
        !          1195: ** [checksum VFS shim] only.
        !          1196: **
        !          1197: ** <li>[[SQLITE_FCNTL_RESET_CACHE]]
        !          1198: ** If there is currently no transaction open on the database, and the
        !          1199: ** database is not a temp db, then the [SQLITE_FCNTL_RESET_CACHE] file-control
        !          1200: ** purges the contents of the in-memory page cache. If there is an open
        !          1201: ** transaction, or if the db is a temp-db, this opcode is a no-op, not an error.
1.3       misho    1202: ** </ul>
1.2       misho    1203: */
                   1204: #define SQLITE_FCNTL_LOCKSTATE               1
1.4       misho    1205: #define SQLITE_FCNTL_GET_LOCKPROXYFILE       2
                   1206: #define SQLITE_FCNTL_SET_LOCKPROXYFILE       3
                   1207: #define SQLITE_FCNTL_LAST_ERRNO              4
1.2       misho    1208: #define SQLITE_FCNTL_SIZE_HINT               5
                   1209: #define SQLITE_FCNTL_CHUNK_SIZE              6
                   1210: #define SQLITE_FCNTL_FILE_POINTER            7
                   1211: #define SQLITE_FCNTL_SYNC_OMITTED            8
                   1212: #define SQLITE_FCNTL_WIN32_AV_RETRY          9
                   1213: #define SQLITE_FCNTL_PERSIST_WAL            10
                   1214: #define SQLITE_FCNTL_OVERWRITE              11
                   1215: #define SQLITE_FCNTL_VFSNAME                12
                   1216: #define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
1.3       misho    1217: #define SQLITE_FCNTL_PRAGMA                 14
                   1218: #define SQLITE_FCNTL_BUSYHANDLER            15
                   1219: #define SQLITE_FCNTL_TEMPFILENAME           16
1.4       misho    1220: #define SQLITE_FCNTL_MMAP_SIZE              18
                   1221: #define SQLITE_FCNTL_TRACE                  19
                   1222: #define SQLITE_FCNTL_HAS_MOVED              20
                   1223: #define SQLITE_FCNTL_SYNC                   21
                   1224: #define SQLITE_FCNTL_COMMIT_PHASETWO        22
                   1225: #define SQLITE_FCNTL_WIN32_SET_HANDLE       23
                   1226: #define SQLITE_FCNTL_WAL_BLOCK              24
                   1227: #define SQLITE_FCNTL_ZIPVFS                 25
                   1228: #define SQLITE_FCNTL_RBU                    26
                   1229: #define SQLITE_FCNTL_VFS_POINTER            27
                   1230: #define SQLITE_FCNTL_JOURNAL_POINTER        28
1.5       misho    1231: #define SQLITE_FCNTL_WIN32_GET_HANDLE       29
                   1232: #define SQLITE_FCNTL_PDB                    30
                   1233: #define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE     31
                   1234: #define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE    32
                   1235: #define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE  33
                   1236: #define SQLITE_FCNTL_LOCK_TIMEOUT           34
                   1237: #define SQLITE_FCNTL_DATA_VERSION           35
                   1238: #define SQLITE_FCNTL_SIZE_LIMIT             36
                   1239: #define SQLITE_FCNTL_CKPT_DONE              37
                   1240: #define SQLITE_FCNTL_RESERVE_BYTES          38
                   1241: #define SQLITE_FCNTL_CKPT_START             39
1.6.2.1 ! misho    1242: #define SQLITE_FCNTL_EXTERNAL_READER        40
        !          1243: #define SQLITE_FCNTL_CKSM_FILE              41
        !          1244: #define SQLITE_FCNTL_RESET_CACHE            42
1.4       misho    1245: 
                   1246: /* deprecated names */
                   1247: #define SQLITE_GET_LOCKPROXYFILE      SQLITE_FCNTL_GET_LOCKPROXYFILE
                   1248: #define SQLITE_SET_LOCKPROXYFILE      SQLITE_FCNTL_SET_LOCKPROXYFILE
                   1249: #define SQLITE_LAST_ERRNO             SQLITE_FCNTL_LAST_ERRNO
                   1250: 
1.2       misho    1251: 
                   1252: /*
                   1253: ** CAPI3REF: Mutex Handle
                   1254: **
                   1255: ** The mutex module within SQLite defines [sqlite3_mutex] to be an
                   1256: ** abstract type for a mutex object.  The SQLite core never looks
                   1257: ** at the internal representation of an [sqlite3_mutex].  It only
                   1258: ** deals with pointers to the [sqlite3_mutex] object.
                   1259: **
                   1260: ** Mutexes are created using [sqlite3_mutex_alloc()].
                   1261: */
                   1262: typedef struct sqlite3_mutex sqlite3_mutex;
                   1263: 
                   1264: /*
1.4       misho    1265: ** CAPI3REF: Loadable Extension Thunk
                   1266: **
                   1267: ** A pointer to the opaque sqlite3_api_routines structure is passed as
                   1268: ** the third parameter to entry points of [loadable extensions].  This
                   1269: ** structure must be typedefed in order to work around compiler warnings
                   1270: ** on some platforms.
                   1271: */
                   1272: typedef struct sqlite3_api_routines sqlite3_api_routines;
                   1273: 
                   1274: /*
1.6.2.1 ! misho    1275: ** CAPI3REF: File Name
        !          1276: **
        !          1277: ** Type [sqlite3_filename] is used by SQLite to pass filenames to the
        !          1278: ** xOpen method of a [VFS]. It may be cast to (const char*) and treated
        !          1279: ** as a normal, nul-terminated, UTF-8 buffer containing the filename, but
        !          1280: ** may also be passed to special APIs such as:
        !          1281: **
        !          1282: ** <ul>
        !          1283: ** <li>  sqlite3_filename_database()
        !          1284: ** <li>  sqlite3_filename_journal()
        !          1285: ** <li>  sqlite3_filename_wal()
        !          1286: ** <li>  sqlite3_uri_parameter()
        !          1287: ** <li>  sqlite3_uri_boolean()
        !          1288: ** <li>  sqlite3_uri_int64()
        !          1289: ** <li>  sqlite3_uri_key()
        !          1290: ** </ul>
        !          1291: */
        !          1292: typedef const char *sqlite3_filename;
        !          1293: 
        !          1294: /*
1.2       misho    1295: ** CAPI3REF: OS Interface Object
                   1296: **
                   1297: ** An instance of the sqlite3_vfs object defines the interface between
                   1298: ** the SQLite core and the underlying operating system.  The "vfs"
                   1299: ** in the name of the object stands for "virtual file system".  See
                   1300: ** the [VFS | VFS documentation] for further information.
                   1301: **
1.5       misho    1302: ** The VFS interface is sometimes extended by adding new methods onto
                   1303: ** the end.  Each time such an extension occurs, the iVersion field
                   1304: ** is incremented.  The iVersion value started out as 1 in
                   1305: ** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2
                   1306: ** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased
                   1307: ** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6].  Additional fields
                   1308: ** may be appended to the sqlite3_vfs object and the iVersion value
                   1309: ** may increase again in future versions of SQLite.
                   1310: ** Note that due to an oversight, the structure
                   1311: ** of the sqlite3_vfs object changed in the transition from
                   1312: ** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0]
                   1313: ** and yet the iVersion field was not increased.
1.2       misho    1314: **
                   1315: ** The szOsFile field is the size of the subclassed [sqlite3_file]
                   1316: ** structure used by this VFS.  mxPathname is the maximum length of
                   1317: ** a pathname in this VFS.
                   1318: **
                   1319: ** Registered sqlite3_vfs objects are kept on a linked list formed by
                   1320: ** the pNext pointer.  The [sqlite3_vfs_register()]
                   1321: ** and [sqlite3_vfs_unregister()] interfaces manage this list
                   1322: ** in a thread-safe way.  The [sqlite3_vfs_find()] interface
                   1323: ** searches the list.  Neither the application code nor the VFS
                   1324: ** implementation should use the pNext pointer.
                   1325: **
                   1326: ** The pNext field is the only field in the sqlite3_vfs
                   1327: ** structure that SQLite will ever modify.  SQLite will only access
                   1328: ** or modify this field while holding a particular static mutex.
                   1329: ** The application should never modify anything within the sqlite3_vfs
                   1330: ** object once the object has been registered.
                   1331: **
                   1332: ** The zName field holds the name of the VFS module.  The name must
                   1333: ** be unique across all VFS modules.
                   1334: **
                   1335: ** [[sqlite3_vfs.xOpen]]
                   1336: ** ^SQLite guarantees that the zFilename parameter to xOpen
                   1337: ** is either a NULL pointer or string obtained
                   1338: ** from xFullPathname() with an optional suffix added.
                   1339: ** ^If a suffix is added to the zFilename parameter, it will
                   1340: ** consist of a single "-" character followed by no more than
                   1341: ** 11 alphanumeric and/or "-" characters.
                   1342: ** ^SQLite further guarantees that
                   1343: ** the string will be valid and unchanged until xClose() is
                   1344: ** called. Because of the previous sentence,
                   1345: ** the [sqlite3_file] can safely store a pointer to the
                   1346: ** filename if it needs to remember the filename for some reason.
                   1347: ** If the zFilename parameter to xOpen is a NULL pointer then xOpen
1.5       misho    1348: ** must invent its own temporary name for the file.  ^Whenever the
1.2       misho    1349: ** xFilename parameter is NULL it will also be the case that the
                   1350: ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
                   1351: **
                   1352: ** The flags argument to xOpen() includes all bits set in
                   1353: ** the flags argument to [sqlite3_open_v2()].  Or if [sqlite3_open()]
                   1354: ** or [sqlite3_open16()] is used, then flags includes at least
1.5       misho    1355: ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
1.2       misho    1356: ** If xOpen() opens a file read-only then it sets *pOutFlags to
                   1357: ** include [SQLITE_OPEN_READONLY].  Other bits in *pOutFlags may be set.
                   1358: **
                   1359: ** ^(SQLite will also add one of the following flags to the xOpen()
                   1360: ** call, depending on the object being opened:
                   1361: **
                   1362: ** <ul>
                   1363: ** <li>  [SQLITE_OPEN_MAIN_DB]
                   1364: ** <li>  [SQLITE_OPEN_MAIN_JOURNAL]
                   1365: ** <li>  [SQLITE_OPEN_TEMP_DB]
                   1366: ** <li>  [SQLITE_OPEN_TEMP_JOURNAL]
                   1367: ** <li>  [SQLITE_OPEN_TRANSIENT_DB]
                   1368: ** <li>  [SQLITE_OPEN_SUBJOURNAL]
1.5       misho    1369: ** <li>  [SQLITE_OPEN_SUPER_JOURNAL]
1.2       misho    1370: ** <li>  [SQLITE_OPEN_WAL]
                   1371: ** </ul>)^
                   1372: **
                   1373: ** The file I/O implementation can use the object type flags to
                   1374: ** change the way it deals with files.  For example, an application
                   1375: ** that does not care about crash recovery or rollback might make
                   1376: ** the open of a journal file a no-op.  Writes to this journal would
                   1377: ** also be no-ops, and any attempt to read the journal would return
                   1378: ** SQLITE_IOERR.  Or the implementation might recognize that a database
                   1379: ** file will be doing page-aligned sector reads and writes in a random
                   1380: ** order and set up its I/O subsystem accordingly.
                   1381: **
                   1382: ** SQLite might also add one of the following flags to the xOpen method:
                   1383: **
                   1384: ** <ul>
                   1385: ** <li> [SQLITE_OPEN_DELETEONCLOSE]
                   1386: ** <li> [SQLITE_OPEN_EXCLUSIVE]
                   1387: ** </ul>
                   1388: **
                   1389: ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
                   1390: ** deleted when it is closed.  ^The [SQLITE_OPEN_DELETEONCLOSE]
                   1391: ** will be set for TEMP databases and their journals, transient
                   1392: ** databases, and subjournals.
                   1393: **
                   1394: ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
                   1395: ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
                   1396: ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
1.5       misho    1397: ** API.  The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
1.2       misho    1398: ** SQLITE_OPEN_CREATE, is used to indicate that file should always
                   1399: ** be created, and that it is an error if it already exists.
1.5       misho    1400: ** It is <i>not</i> used to indicate the file should be opened
1.2       misho    1401: ** for exclusive access.
                   1402: **
                   1403: ** ^At least szOsFile bytes of memory are allocated by SQLite
1.5       misho    1404: ** to hold the [sqlite3_file] structure passed as the third
1.2       misho    1405: ** argument to xOpen.  The xOpen method does not have to
                   1406: ** allocate the structure; it should just fill it in.  Note that
                   1407: ** the xOpen method must set the sqlite3_file.pMethods to either
                   1408: ** a valid [sqlite3_io_methods] object or to NULL.  xOpen must do
                   1409: ** this even if the open fails.  SQLite expects that the sqlite3_file.pMethods
                   1410: ** element will be valid after xOpen returns regardless of the success
                   1411: ** or failure of the xOpen call.
                   1412: **
                   1413: ** [[sqlite3_vfs.xAccess]]
                   1414: ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
                   1415: ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
                   1416: ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
1.5       misho    1417: ** to test whether a file is at least readable.  The SQLITE_ACCESS_READ
                   1418: ** flag is never actually used and is not implemented in the built-in
                   1419: ** VFSes of SQLite.  The file is named by the second argument and can be a
                   1420: ** directory. The xAccess method returns [SQLITE_OK] on success or some
                   1421: ** non-zero error code if there is an I/O error or if the name of
                   1422: ** the file given in the second argument is illegal.  If SQLITE_OK
                   1423: ** is returned, then non-zero or zero is written into *pResOut to indicate
                   1424: ** whether or not the file is accessible.
1.2       misho    1425: **
                   1426: ** ^SQLite will always allocate at least mxPathname+1 bytes for the
                   1427: ** output buffer xFullPathname.  The exact size of the output buffer
                   1428: ** is also passed as a parameter to both  methods. If the output buffer
                   1429: ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
                   1430: ** handled as a fatal error by SQLite, vfs implementations should endeavor
                   1431: ** to prevent this by setting mxPathname to a sufficiently large value.
                   1432: **
                   1433: ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
                   1434: ** interfaces are not strictly a part of the filesystem, but they are
                   1435: ** included in the VFS structure for completeness.
                   1436: ** The xRandomness() function attempts to return nBytes bytes
                   1437: ** of good-quality randomness into zOut.  The return value is
                   1438: ** the actual number of bytes of randomness obtained.
                   1439: ** The xSleep() method causes the calling thread to sleep for at
                   1440: ** least the number of microseconds given.  ^The xCurrentTime()
                   1441: ** method returns a Julian Day Number for the current date and time as
                   1442: ** a floating point value.
                   1443: ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
1.5       misho    1444: ** Day Number multiplied by 86400000 (the number of milliseconds in
                   1445: ** a 24-hour day).
1.2       misho    1446: ** ^SQLite will use the xCurrentTimeInt64() method to get the current
1.5       misho    1447: ** date and time if that method is available (if iVersion is 2 or
1.2       misho    1448: ** greater and the function pointer is not NULL) and will fall back
                   1449: ** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
                   1450: **
                   1451: ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
                   1452: ** are not used by the SQLite core.  These optional interfaces are provided
1.5       misho    1453: ** by some VFSes to facilitate testing of the VFS code. By overriding
1.2       misho    1454: ** system calls with functions under its control, a test program can
                   1455: ** simulate faults and error conditions that would otherwise be difficult
                   1456: ** or impossible to induce.  The set of system calls that can be overridden
                   1457: ** varies from one VFS to another, and from one version of the same VFS to the
                   1458: ** next.  Applications that use these interfaces must be prepared for any
                   1459: ** or all of these interfaces to be NULL or for their behavior to change
                   1460: ** from one release to the next.  Applications must not attempt to access
                   1461: ** any of these methods if the iVersion of the VFS is less than 3.
                   1462: */
                   1463: typedef struct sqlite3_vfs sqlite3_vfs;
                   1464: typedef void (*sqlite3_syscall_ptr)(void);
                   1465: struct sqlite3_vfs {
                   1466:   int iVersion;            /* Structure version number (currently 3) */
                   1467:   int szOsFile;            /* Size of subclassed sqlite3_file */
                   1468:   int mxPathname;          /* Maximum file pathname length */
                   1469:   sqlite3_vfs *pNext;      /* Next registered VFS */
                   1470:   const char *zName;       /* Name of this virtual file system */
                   1471:   void *pAppData;          /* Pointer to application-specific data */
1.6.2.1 ! misho    1472:   int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*,
1.2       misho    1473:                int flags, int *pOutFlags);
                   1474:   int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
                   1475:   int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
                   1476:   int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
                   1477:   void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
                   1478:   void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
                   1479:   void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
                   1480:   void (*xDlClose)(sqlite3_vfs*, void*);
                   1481:   int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
                   1482:   int (*xSleep)(sqlite3_vfs*, int microseconds);
                   1483:   int (*xCurrentTime)(sqlite3_vfs*, double*);
                   1484:   int (*xGetLastError)(sqlite3_vfs*, int, char *);
                   1485:   /*
                   1486:   ** The methods above are in version 1 of the sqlite_vfs object
                   1487:   ** definition.  Those that follow are added in version 2 or later
                   1488:   */
                   1489:   int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
                   1490:   /*
                   1491:   ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
                   1492:   ** Those below are for version 3 and greater.
                   1493:   */
                   1494:   int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
                   1495:   sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
                   1496:   const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
                   1497:   /*
                   1498:   ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
1.4       misho    1499:   ** New fields may be appended in future versions.  The iVersion
1.5       misho    1500:   ** value will increment whenever this happens.
1.2       misho    1501:   */
                   1502: };
                   1503: 
                   1504: /*
                   1505: ** CAPI3REF: Flags for the xAccess VFS method
                   1506: **
                   1507: ** These integer constants can be used as the third parameter to
                   1508: ** the xAccess method of an [sqlite3_vfs] object.  They determine
                   1509: ** what kind of permissions the xAccess method is looking for.
                   1510: ** With SQLITE_ACCESS_EXISTS, the xAccess method
                   1511: ** simply checks whether the file exists.
                   1512: ** With SQLITE_ACCESS_READWRITE, the xAccess method
                   1513: ** checks whether the named directory is both readable and writable
                   1514: ** (in other words, if files can be added, removed, and renamed within
                   1515: ** the directory).
                   1516: ** The SQLITE_ACCESS_READWRITE constant is currently used only by the
                   1517: ** [temp_store_directory pragma], though this could change in a future
                   1518: ** release of SQLite.
                   1519: ** With SQLITE_ACCESS_READ, the xAccess method
                   1520: ** checks whether the file is readable.  The SQLITE_ACCESS_READ constant is
                   1521: ** currently unused, though it might be used in a future release of
                   1522: ** SQLite.
                   1523: */
                   1524: #define SQLITE_ACCESS_EXISTS    0
                   1525: #define SQLITE_ACCESS_READWRITE 1   /* Used by PRAGMA temp_store_directory */
                   1526: #define SQLITE_ACCESS_READ      2   /* Unused */
                   1527: 
                   1528: /*
                   1529: ** CAPI3REF: Flags for the xShmLock VFS method
                   1530: **
                   1531: ** These integer constants define the various locking operations
                   1532: ** allowed by the xShmLock method of [sqlite3_io_methods].  The
                   1533: ** following are the only legal combinations of flags to the
                   1534: ** xShmLock method:
                   1535: **
                   1536: ** <ul>
                   1537: ** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
                   1538: ** <li>  SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
                   1539: ** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
                   1540: ** <li>  SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
                   1541: ** </ul>
                   1542: **
                   1543: ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
1.5       misho    1544: ** was given on the corresponding lock.
1.2       misho    1545: **
                   1546: ** The xShmLock method can transition between unlocked and SHARED or
                   1547: ** between unlocked and EXCLUSIVE.  It cannot transition between SHARED
                   1548: ** and EXCLUSIVE.
                   1549: */
                   1550: #define SQLITE_SHM_UNLOCK       1
                   1551: #define SQLITE_SHM_LOCK         2
                   1552: #define SQLITE_SHM_SHARED       4
                   1553: #define SQLITE_SHM_EXCLUSIVE    8
                   1554: 
                   1555: /*
                   1556: ** CAPI3REF: Maximum xShmLock index
                   1557: **
                   1558: ** The xShmLock method on [sqlite3_io_methods] may use values
                   1559: ** between 0 and this upper bound as its "offset" argument.
                   1560: ** The SQLite core will never attempt to acquire or release a
                   1561: ** lock outside of this range
                   1562: */
                   1563: #define SQLITE_SHM_NLOCK        8
                   1564: 
                   1565: 
                   1566: /*
                   1567: ** CAPI3REF: Initialize The SQLite Library
                   1568: **
                   1569: ** ^The sqlite3_initialize() routine initializes the
                   1570: ** SQLite library.  ^The sqlite3_shutdown() routine
                   1571: ** deallocates any resources that were allocated by sqlite3_initialize().
                   1572: ** These routines are designed to aid in process initialization and
                   1573: ** shutdown on embedded systems.  Workstation applications using
                   1574: ** SQLite normally do not need to invoke either of these routines.
                   1575: **
                   1576: ** A call to sqlite3_initialize() is an "effective" call if it is
                   1577: ** the first time sqlite3_initialize() is invoked during the lifetime of
                   1578: ** the process, or if it is the first time sqlite3_initialize() is invoked
                   1579: ** following a call to sqlite3_shutdown().  ^(Only an effective call
                   1580: ** of sqlite3_initialize() does any initialization.  All other calls
                   1581: ** are harmless no-ops.)^
                   1582: **
                   1583: ** A call to sqlite3_shutdown() is an "effective" call if it is the first
                   1584: ** call to sqlite3_shutdown() since the last sqlite3_initialize().  ^(Only
                   1585: ** an effective call to sqlite3_shutdown() does any deinitialization.
                   1586: ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
                   1587: **
                   1588: ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
                   1589: ** is not.  The sqlite3_shutdown() interface must only be called from a
                   1590: ** single thread.  All open [database connections] must be closed and all
                   1591: ** other SQLite resources must be deallocated prior to invoking
                   1592: ** sqlite3_shutdown().
                   1593: **
                   1594: ** Among other things, ^sqlite3_initialize() will invoke
                   1595: ** sqlite3_os_init().  Similarly, ^sqlite3_shutdown()
                   1596: ** will invoke sqlite3_os_end().
                   1597: **
                   1598: ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
                   1599: ** ^If for some reason, sqlite3_initialize() is unable to initialize
                   1600: ** the library (perhaps it is unable to allocate a needed resource such
                   1601: ** as a mutex) it returns an [error code] other than [SQLITE_OK].
                   1602: **
                   1603: ** ^The sqlite3_initialize() routine is called internally by many other
                   1604: ** SQLite interfaces so that an application usually does not need to
                   1605: ** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
                   1606: ** calls sqlite3_initialize() so the SQLite library will be automatically
                   1607: ** initialized when [sqlite3_open()] is called if it has not be initialized
                   1608: ** already.  ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
                   1609: ** compile-time option, then the automatic calls to sqlite3_initialize()
                   1610: ** are omitted and the application must call sqlite3_initialize() directly
                   1611: ** prior to using any other SQLite interface.  For maximum portability,
                   1612: ** it is recommended that applications always invoke sqlite3_initialize()
                   1613: ** directly prior to using any other SQLite interface.  Future releases
                   1614: ** of SQLite may require this.  In other words, the behavior exhibited
                   1615: ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
                   1616: ** default behavior in some future release of SQLite.
                   1617: **
                   1618: ** The sqlite3_os_init() routine does operating-system specific
                   1619: ** initialization of the SQLite library.  The sqlite3_os_end()
                   1620: ** routine undoes the effect of sqlite3_os_init().  Typical tasks
                   1621: ** performed by these routines include allocation or deallocation
                   1622: ** of static resources, initialization of global variables,
                   1623: ** setting up a default [sqlite3_vfs] module, or setting up
                   1624: ** a default configuration using [sqlite3_config()].
                   1625: **
                   1626: ** The application should never invoke either sqlite3_os_init()
                   1627: ** or sqlite3_os_end() directly.  The application should only invoke
                   1628: ** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
                   1629: ** interface is called automatically by sqlite3_initialize() and
                   1630: ** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
                   1631: ** implementations for sqlite3_os_init() and sqlite3_os_end()
                   1632: ** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
                   1633: ** When [custom builds | built for other platforms]
                   1634: ** (using the [SQLITE_OS_OTHER=1] compile-time
                   1635: ** option) the application must supply a suitable implementation for
                   1636: ** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
                   1637: ** implementation of sqlite3_os_init() or sqlite3_os_end()
                   1638: ** must return [SQLITE_OK] on success and some other [error code] upon
                   1639: ** failure.
                   1640: */
                   1641: SQLITE_API int sqlite3_initialize(void);
                   1642: SQLITE_API int sqlite3_shutdown(void);
                   1643: SQLITE_API int sqlite3_os_init(void);
                   1644: SQLITE_API int sqlite3_os_end(void);
                   1645: 
                   1646: /*
                   1647: ** CAPI3REF: Configuring The SQLite Library
                   1648: **
                   1649: ** The sqlite3_config() interface is used to make global configuration
                   1650: ** changes to SQLite in order to tune SQLite to the specific needs of
                   1651: ** the application.  The default configuration is recommended for most
                   1652: ** applications and so this routine is usually not necessary.  It is
                   1653: ** provided to support rare applications with unusual needs.
                   1654: **
1.4       misho    1655: ** <b>The sqlite3_config() interface is not threadsafe. The application
                   1656: ** must ensure that no other SQLite interfaces are invoked by other
                   1657: ** threads while sqlite3_config() is running.</b>
                   1658: **
1.2       misho    1659: ** The first argument to sqlite3_config() is an integer
                   1660: ** [configuration option] that determines
                   1661: ** what property of SQLite is to be configured.  Subsequent arguments
                   1662: ** vary depending on the [configuration option]
                   1663: ** in the first argument.
                   1664: **
1.6.2.1 ! misho    1665: ** For most configuration options, the sqlite3_config() interface
        !          1666: ** may only be invoked prior to library initialization using
        !          1667: ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
        !          1668: ** The exceptional configuration options that may be invoked at any time
        !          1669: ** are called "anytime configuration options".
        !          1670: ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
        !          1671: ** [sqlite3_shutdown()] with a first argument that is not an anytime
        !          1672: ** configuration option, then the sqlite3_config() call will return SQLITE_MISUSE.
        !          1673: ** Note, however, that ^sqlite3_config() can be called as part of the
        !          1674: ** implementation of an application-defined [sqlite3_os_init()].
        !          1675: **
1.2       misho    1676: ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
                   1677: ** ^If the option is unknown or SQLite is unable to set the option
                   1678: ** then this routine returns a non-zero [error code].
                   1679: */
                   1680: SQLITE_API int sqlite3_config(int, ...);
                   1681: 
                   1682: /*
                   1683: ** CAPI3REF: Configure database connections
1.4       misho    1684: ** METHOD: sqlite3
1.2       misho    1685: **
                   1686: ** The sqlite3_db_config() interface is used to make configuration
                   1687: ** changes to a [database connection].  The interface is similar to
                   1688: ** [sqlite3_config()] except that the changes apply to a single
                   1689: ** [database connection] (specified in the first argument).
                   1690: **
                   1691: ** The second argument to sqlite3_db_config(D,V,...)  is the
1.5       misho    1692: ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
1.2       misho    1693: ** that indicates what aspect of the [database connection] is being configured.
                   1694: ** Subsequent arguments vary depending on the configuration verb.
                   1695: **
                   1696: ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
                   1697: ** the call is considered successful.
                   1698: */
                   1699: SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
                   1700: 
                   1701: /*
                   1702: ** CAPI3REF: Memory Allocation Routines
                   1703: **
                   1704: ** An instance of this object defines the interface between SQLite
                   1705: ** and low-level memory allocation routines.
                   1706: **
                   1707: ** This object is used in only one place in the SQLite interface.
                   1708: ** A pointer to an instance of this object is the argument to
                   1709: ** [sqlite3_config()] when the configuration option is
1.5       misho    1710: ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
1.2       misho    1711: ** By creating an instance of this object
                   1712: ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
                   1713: ** during configuration, an application can specify an alternative
                   1714: ** memory allocation subsystem for SQLite to use for all of its
                   1715: ** dynamic memory needs.
                   1716: **
                   1717: ** Note that SQLite comes with several [built-in memory allocators]
                   1718: ** that are perfectly adequate for the overwhelming majority of applications
                   1719: ** and that this object is only useful to a tiny minority of applications
                   1720: ** with specialized memory allocation requirements.  This object is
                   1721: ** also used during testing of SQLite in order to specify an alternative
                   1722: ** memory allocator that simulates memory out-of-memory conditions in
                   1723: ** order to verify that SQLite recovers gracefully from such
                   1724: ** conditions.
                   1725: **
                   1726: ** The xMalloc, xRealloc, and xFree methods must work like the
                   1727: ** malloc(), realloc() and free() functions from the standard C library.
                   1728: ** ^SQLite guarantees that the second argument to
                   1729: ** xRealloc is always a value returned by a prior call to xRoundup.
                   1730: **
                   1731: ** xSize should return the allocated size of a memory allocation
                   1732: ** previously obtained from xMalloc or xRealloc.  The allocated size
                   1733: ** is always at least as big as the requested size but may be larger.
                   1734: **
                   1735: ** The xRoundup method returns what would be the allocated size of
                   1736: ** a memory allocation given a particular requested size.  Most memory
                   1737: ** allocators round up memory allocations at least to the next multiple
                   1738: ** of 8.  Some allocators round up to a larger multiple or to a power of 2.
                   1739: ** Every memory allocation request coming in through [sqlite3_malloc()]
1.5       misho    1740: ** or [sqlite3_realloc()] first calls xRoundup.  If xRoundup returns 0,
1.2       misho    1741: ** that causes the corresponding memory allocation to fail.
                   1742: **
1.4       misho    1743: ** The xInit method initializes the memory allocator.  For example,
1.5       misho    1744: ** it might allocate any required mutexes or initialize internal data
1.2       misho    1745: ** structures.  The xShutdown method is invoked (indirectly) by
                   1746: ** [sqlite3_shutdown()] and should deallocate any resources acquired
                   1747: ** by xInit.  The pAppData pointer is used as the only parameter to
                   1748: ** xInit and xShutdown.
                   1749: **
1.5       misho    1750: ** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes
1.2       misho    1751: ** the xInit method, so the xInit method need not be threadsafe.  The
                   1752: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
                   1753: ** not need to be threadsafe either.  For all other methods, SQLite
                   1754: ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
                   1755: ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
                   1756: ** it is by default) and so the methods are automatically serialized.
                   1757: ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
                   1758: ** methods must be threadsafe or else make their own arrangements for
                   1759: ** serialization.
                   1760: **
                   1761: ** SQLite will never invoke xInit() more than once without an intervening
                   1762: ** call to xShutdown().
                   1763: */
                   1764: typedef struct sqlite3_mem_methods sqlite3_mem_methods;
                   1765: struct sqlite3_mem_methods {
                   1766:   void *(*xMalloc)(int);         /* Memory allocation function */
                   1767:   void (*xFree)(void*);          /* Free a prior allocation */
                   1768:   void *(*xRealloc)(void*,int);  /* Resize an allocation */
                   1769:   int (*xSize)(void*);           /* Return the size of an allocation */
                   1770:   int (*xRoundup)(int);          /* Round up request size to allocation size */
                   1771:   int (*xInit)(void*);           /* Initialize the memory allocator */
                   1772:   void (*xShutdown)(void*);      /* Deinitialize the memory allocator */
                   1773:   void *pAppData;                /* Argument to xInit() and xShutdown() */
                   1774: };
                   1775: 
                   1776: /*
                   1777: ** CAPI3REF: Configuration Options
                   1778: ** KEYWORDS: {configuration option}
                   1779: **
                   1780: ** These constants are the available integer configuration options that
                   1781: ** can be passed as the first argument to the [sqlite3_config()] interface.
                   1782: **
1.6.2.1 ! misho    1783: ** Most of the configuration options for sqlite3_config()
        !          1784: ** will only work if invoked prior to [sqlite3_initialize()] or after
        !          1785: ** [sqlite3_shutdown()].  The few exceptions to this rule are called
        !          1786: ** "anytime configuration options".
        !          1787: ** ^Calling [sqlite3_config()] with a first argument that is not an
        !          1788: ** anytime configuration option in between calls to [sqlite3_initialize()] and
        !          1789: ** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE.
        !          1790: **
        !          1791: ** The set of anytime configuration options can change (by insertions
        !          1792: ** and/or deletions) from one release of SQLite to the next.
        !          1793: ** As of SQLite version 3.42.0, the complete set of anytime configuration
        !          1794: ** options is:
        !          1795: ** <ul>
        !          1796: ** <li> SQLITE_CONFIG_LOG
        !          1797: ** <li> SQLITE_CONFIG_PCACHE_HDRSZ
        !          1798: ** </ul>
        !          1799: **
1.2       misho    1800: ** New configuration options may be added in future releases of SQLite.
                   1801: ** Existing configuration options might be discontinued.  Applications
                   1802: ** should check the return code from [sqlite3_config()] to make sure that
                   1803: ** the call worked.  The [sqlite3_config()] interface will return a
                   1804: ** non-zero [error code] if a discontinued or unsupported configuration option
                   1805: ** is invoked.
                   1806: **
                   1807: ** <dl>
                   1808: ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
                   1809: ** <dd>There are no arguments to this option.  ^This option sets the
                   1810: ** [threading mode] to Single-thread.  In other words, it disables
                   1811: ** all mutexing and puts SQLite into a mode where it can only be used
                   1812: ** by a single thread.   ^If SQLite is compiled with
                   1813: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
                   1814: ** it is not possible to change the [threading mode] from its default
1.5       misho    1815: ** value of Single-thread and so [sqlite3_config()] will return
1.2       misho    1816: ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
                   1817: ** configuration option.</dd>
                   1818: **
                   1819: ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
                   1820: ** <dd>There are no arguments to this option.  ^This option sets the
                   1821: ** [threading mode] to Multi-thread.  In other words, it disables
                   1822: ** mutexing on [database connection] and [prepared statement] objects.
                   1823: ** The application is responsible for serializing access to
                   1824: ** [database connections] and [prepared statements].  But other mutexes
                   1825: ** are enabled so that SQLite will be safe to use in a multi-threaded
                   1826: ** environment as long as no two threads attempt to use the same
                   1827: ** [database connection] at the same time.  ^If SQLite is compiled with
                   1828: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
                   1829: ** it is not possible to set the Multi-thread [threading mode] and
                   1830: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
                   1831: ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
                   1832: **
                   1833: ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
                   1834: ** <dd>There are no arguments to this option.  ^This option sets the
                   1835: ** [threading mode] to Serialized. In other words, this option enables
                   1836: ** all mutexes including the recursive
                   1837: ** mutexes on [database connection] and [prepared statement] objects.
                   1838: ** In this mode (which is the default when SQLite is compiled with
                   1839: ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
                   1840: ** to [database connections] and [prepared statements] so that the
                   1841: ** application is free to use the same [database connection] or the
                   1842: ** same [prepared statement] in different threads at the same time.
                   1843: ** ^If SQLite is compiled with
                   1844: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
                   1845: ** it is not possible to set the Serialized [threading mode] and
                   1846: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
                   1847: ** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
                   1848: **
                   1849: ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
1.5       misho    1850: ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is
1.4       misho    1851: ** a pointer to an instance of the [sqlite3_mem_methods] structure.
                   1852: ** The argument specifies
1.2       misho    1853: ** alternative low-level memory allocation routines to be used in place of
                   1854: ** the memory allocation routines built into SQLite.)^ ^SQLite makes
                   1855: ** its own private copy of the content of the [sqlite3_mem_methods] structure
                   1856: ** before the [sqlite3_config()] call returns.</dd>
                   1857: **
                   1858: ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
1.4       misho    1859: ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which
                   1860: ** is a pointer to an instance of the [sqlite3_mem_methods] structure.
                   1861: ** The [sqlite3_mem_methods]
1.2       misho    1862: ** structure is filled with the currently defined memory allocation routines.)^
                   1863: ** This option can be used to overload the default memory allocation
                   1864: ** routines with a wrapper that simulations memory allocation failure or
                   1865: ** tracks memory usage, for example. </dd>
                   1866: **
1.5       misho    1867: ** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt>
                   1868: ** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of
                   1869: ** type int, interpreted as a boolean, which if true provides a hint to
                   1870: ** SQLite that it should avoid large memory allocations if possible.
                   1871: ** SQLite will run faster if it is free to make large memory allocations,
                   1872: ** but some application might prefer to run slower in exchange for
                   1873: ** guarantees about memory fragmentation that are possible if large
                   1874: ** allocations are avoided.  This hint is normally off.
                   1875: ** </dd>
                   1876: **
1.2       misho    1877: ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
1.4       misho    1878: ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,
                   1879: ** interpreted as a boolean, which enables or disables the collection of
                   1880: ** memory allocation statistics. ^(When memory allocation statistics are
                   1881: ** disabled, the following SQLite interfaces become non-operational:
1.2       misho    1882: **   <ul>
1.5       misho    1883: **   <li> [sqlite3_hard_heap_limit64()]
1.2       misho    1884: **   <li> [sqlite3_memory_used()]
                   1885: **   <li> [sqlite3_memory_highwater()]
                   1886: **   <li> [sqlite3_soft_heap_limit64()]
1.4       misho    1887: **   <li> [sqlite3_status64()]
1.2       misho    1888: **   </ul>)^
                   1889: ** ^Memory allocation statistics are enabled by default unless SQLite is
                   1890: ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
                   1891: ** allocation statistics are disabled by default.
                   1892: ** </dd>
                   1893: **
                   1894: ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
1.5       misho    1895: ** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used.
1.4       misho    1896: ** </dd>
1.2       misho    1897: **
                   1898: ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
1.4       misho    1899: ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool
                   1900: ** that SQLite can use for the database page cache with the default page
1.5       misho    1901: ** cache implementation.
                   1902: ** This configuration option is a no-op if an application-defined page
1.4       misho    1903: ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].
                   1904: ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to
                   1905: ** 8-byte aligned memory (pMem), the size of each page cache line (sz),
                   1906: ** and the number of cache lines (N).
1.2       misho    1907: ** The sz argument should be the size of the largest database page
1.4       misho    1908: ** (a power of two between 512 and 65536) plus some extra bytes for each
                   1909: ** page header.  ^The number of extra bytes needed by the page header
                   1910: ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].
                   1911: ** ^It is harmless, apart from the wasted memory,
                   1912: ** for the sz parameter to be larger than necessary.  The pMem
                   1913: ** argument must be either a NULL pointer or a pointer to an 8-byte
                   1914: ** aligned block of memory of at least sz*N bytes, otherwise
                   1915: ** subsequent behavior is undefined.
                   1916: ** ^When pMem is not NULL, SQLite will strive to use the memory provided
                   1917: ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if
                   1918: ** a page cache line is larger than sz bytes or if all of the pMem buffer
                   1919: ** is exhausted.
                   1920: ** ^If pMem is NULL and N is non-zero, then each database connection
                   1921: ** does an initial bulk allocation for page cache memory
                   1922: ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or
                   1923: ** of -1024*N bytes if N is negative, . ^If additional
                   1924: ** page cache memory is needed beyond what is provided by the initial
                   1925: ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each
                   1926: ** additional cache line. </dd>
1.2       misho    1927: **
                   1928: ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
1.5       misho    1929: ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer
1.4       misho    1930: ** that SQLite will use for all of its dynamic memory allocation needs
1.5       misho    1931: ** beyond those provided for by [SQLITE_CONFIG_PAGECACHE].
1.4       misho    1932: ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled
                   1933: ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns
                   1934: ** [SQLITE_ERROR] if invoked otherwise.
                   1935: ** ^There are three arguments to SQLITE_CONFIG_HEAP:
                   1936: ** An 8-byte aligned pointer to the memory,
1.2       misho    1937: ** the number of bytes in the memory buffer, and the minimum allocation size.
                   1938: ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
                   1939: ** to using its default memory allocator (the system malloc() implementation),
                   1940: ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC].  ^If the
1.4       misho    1941: ** memory pointer is not NULL then the alternative memory
1.2       misho    1942: ** allocator is engaged to handle all of SQLites memory allocation needs.
                   1943: ** The first pointer (the memory pointer) must be aligned to an 8-byte
                   1944: ** boundary or subsequent behavior of SQLite will be undefined.
                   1945: ** The minimum allocation size is capped at 2**12. Reasonable values
                   1946: ** for the minimum allocation size are 2**5 through 2**8.</dd>
                   1947: **
                   1948: ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
1.4       misho    1949: ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a
                   1950: ** pointer to an instance of the [sqlite3_mutex_methods] structure.
                   1951: ** The argument specifies alternative low-level mutex routines to be used
                   1952: ** in place the mutex routines built into SQLite.)^  ^SQLite makes a copy of
                   1953: ** the content of the [sqlite3_mutex_methods] structure before the call to
1.2       misho    1954: ** [sqlite3_config()] returns. ^If SQLite is compiled with
                   1955: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
                   1956: ** the entire mutexing subsystem is omitted from the build and hence calls to
                   1957: ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
                   1958: ** return [SQLITE_ERROR].</dd>
                   1959: **
                   1960: ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
1.4       misho    1961: ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which
                   1962: ** is a pointer to an instance of the [sqlite3_mutex_methods] structure.  The
1.2       misho    1963: ** [sqlite3_mutex_methods]
                   1964: ** structure is filled with the currently defined mutex routines.)^
                   1965: ** This option can be used to overload the default mutex allocation
                   1966: ** routines with a wrapper used to track mutex usage for performance
                   1967: ** profiling or testing, for example.   ^If SQLite is compiled with
                   1968: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
                   1969: ** the entire mutexing subsystem is omitted from the build and hence calls to
                   1970: ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
                   1971: ** return [SQLITE_ERROR].</dd>
                   1972: **
                   1973: ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
1.4       misho    1974: ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine
                   1975: ** the default size of lookaside memory on each [database connection].
                   1976: ** The first argument is the
1.2       misho    1977: ** size of each lookaside buffer slot and the second is the number of
1.4       misho    1978: ** slots allocated to each database connection.)^  ^(SQLITE_CONFIG_LOOKASIDE
                   1979: ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
                   1980: ** option to [sqlite3_db_config()] can be used to change the lookaside
1.2       misho    1981: ** configuration on individual connections.)^ </dd>
                   1982: **
                   1983: ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
1.5       misho    1984: ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is
1.4       misho    1985: ** a pointer to an [sqlite3_pcache_methods2] object.  This object specifies
                   1986: ** the interface to a custom page cache implementation.)^
                   1987: ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>
1.2       misho    1988: **
                   1989: ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
1.4       misho    1990: ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which
                   1991: ** is a pointer to an [sqlite3_pcache_methods2] object.  SQLite copies of
                   1992: ** the current page cache implementation into that object.)^ </dd>
1.2       misho    1993: **
                   1994: ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
1.4       misho    1995: ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
                   1996: ** global [error log].
                   1997: ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
1.5       misho    1998: ** function with a call signature of void(*)(void*,int,const char*),
1.2       misho    1999: ** and a pointer to void. ^If the function pointer is not NULL, it is
                   2000: ** invoked by [sqlite3_log()] to process each logging event.  ^If the
                   2001: ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
                   2002: ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
                   2003: ** passed through as the first parameter to the application-defined logger
                   2004: ** function whenever that function is invoked.  ^The second parameter to
                   2005: ** the logger function is a copy of the first parameter to the corresponding
                   2006: ** [sqlite3_log()] call and is intended to be a [result code] or an
                   2007: ** [extended result code].  ^The third parameter passed to the logger is
                   2008: ** log message after formatting via [sqlite3_snprintf()].
                   2009: ** The SQLite logging interface is not reentrant; the logger function
                   2010: ** supplied by the application must not invoke any SQLite interface.
                   2011: ** In a multi-threaded application, the application-defined logger
                   2012: ** function must be threadsafe. </dd>
                   2013: **
                   2014: ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
1.4       misho    2015: ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.
                   2016: ** If non-zero, then URI handling is globally enabled. If the parameter is zero,
                   2017: ** then URI handling is globally disabled.)^ ^If URI handling is globally
                   2018: ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],
                   2019: ** [sqlite3_open16()] or
1.2       misho    2020: ** specified as part of [ATTACH] commands are interpreted as URIs, regardless
                   2021: ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
1.4       misho    2022: ** connection is opened. ^If it is globally disabled, filenames are
1.2       misho    2023: ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
1.4       misho    2024: ** database connection is opened. ^(By default, URI handling is globally
1.2       misho    2025: ** disabled. The default value may be changed by compiling with the
1.4       misho    2026: ** [SQLITE_USE_URI] symbol defined.)^
1.2       misho    2027: **
1.3       misho    2028: ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
1.4       misho    2029: ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer
                   2030: ** argument which is interpreted as a boolean in order to enable or disable
                   2031: ** the use of covering indices for full table scans in the query optimizer.
                   2032: ** ^The default setting is determined
1.3       misho    2033: ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
                   2034: ** if that compile-time option is omitted.
                   2035: ** The ability to disable the use of covering indices for full table scans
                   2036: ** is because some incorrectly coded legacy applications might malfunction
1.4       misho    2037: ** when the optimization is enabled.  Providing the ability to
1.3       misho    2038: ** disable the optimization allows the older, buggy application code to work
                   2039: ** without change even with newer versions of SQLite.
                   2040: **
1.2       misho    2041: ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
1.3       misho    2042: ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
1.2       misho    2043: ** <dd> These options are obsolete and should not be used by new code.
                   2044: ** They are retained for backwards compatibility but are now no-ops.
1.4       misho    2045: ** </dd>
1.3       misho    2046: **
                   2047: ** [[SQLITE_CONFIG_SQLLOG]]
                   2048: ** <dt>SQLITE_CONFIG_SQLLOG
                   2049: ** <dd>This option is only available if sqlite is compiled with the
1.4       misho    2050: ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
1.3       misho    2051: ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
                   2052: ** The second should be of type (void*). The callback is invoked by the library
                   2053: ** in three separate circumstances, identified by the value passed as the
                   2054: ** fourth parameter. If the fourth parameter is 0, then the database connection
                   2055: ** passed as the second argument has just been opened. The third argument
                   2056: ** points to a buffer containing the name of the main database file. If the
                   2057: ** fourth parameter is 1, then the SQL statement that the third parameter
                   2058: ** points to has just been executed. Or, if the fourth parameter is 2, then
                   2059: ** the connection being passed as the second parameter is being closed. The
1.4       misho    2060: ** third parameter is passed NULL In this case.  An example of using this
                   2061: ** configuration option can be seen in the "test_sqllog.c" source file in
                   2062: ** the canonical SQLite source tree.</dd>
                   2063: **
                   2064: ** [[SQLITE_CONFIG_MMAP_SIZE]]
                   2065: ** <dt>SQLITE_CONFIG_MMAP_SIZE
                   2066: ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
                   2067: ** that are the default mmap size limit (the default setting for
                   2068: ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
                   2069: ** ^The default setting can be overridden by each database connection using
                   2070: ** either the [PRAGMA mmap_size] command, or by using the
                   2071: ** [SQLITE_FCNTL_MMAP_SIZE] file control.  ^(The maximum allowed mmap size
                   2072: ** will be silently truncated if necessary so that it does not exceed the
                   2073: ** compile-time maximum mmap size set by the
                   2074: ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^
                   2075: ** ^If either argument to this option is negative, then that argument is
                   2076: ** changed to its compile-time default.
                   2077: **
                   2078: ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]
                   2079: ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE
                   2080: ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is
                   2081: ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro
                   2082: ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value
                   2083: ** that specifies the maximum size of the created heap.
                   2084: **
                   2085: ** [[SQLITE_CONFIG_PCACHE_HDRSZ]]
                   2086: ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ
                   2087: ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which
                   2088: ** is a pointer to an integer and writes into that integer the number of extra
                   2089: ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].
                   2090: ** The amount of extra space required can change depending on the compiler,
                   2091: ** target platform, and SQLite version.
                   2092: **
                   2093: ** [[SQLITE_CONFIG_PMASZ]]
                   2094: ** <dt>SQLITE_CONFIG_PMASZ
                   2095: ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which
                   2096: ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded
                   2097: ** sorter to that integer.  The default minimum PMA Size is set by the
                   2098: ** [SQLITE_SORTER_PMASZ] compile-time option.  New threads are launched
                   2099: ** to help with sort operations when multithreaded sorting
                   2100: ** is enabled (using the [PRAGMA threads] command) and the amount of content
                   2101: ** to be sorted exceeds the page size times the minimum of the
                   2102: ** [PRAGMA cache_size] setting and this value.
                   2103: **
                   2104: ** [[SQLITE_CONFIG_STMTJRNL_SPILL]]
                   2105: ** <dt>SQLITE_CONFIG_STMTJRNL_SPILL
                   2106: ** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which
1.5       misho    2107: ** becomes the [statement journal] spill-to-disk threshold.
1.4       misho    2108: ** [Statement journals] are held in memory until their size (in bytes)
                   2109: ** exceeds this threshold, at which point they are written to disk.
                   2110: ** Or if the threshold is -1, statement journals are always held
                   2111: ** exclusively in memory.
                   2112: ** Since many statement journals never become large, setting the spill
                   2113: ** threshold to a value such as 64KiB can greatly reduce the amount of
                   2114: ** I/O required to support statement rollback.
                   2115: ** The default value for this setting is controlled by the
                   2116: ** [SQLITE_STMTJRNL_SPILL] compile-time option.
1.5       misho    2117: **
                   2118: ** [[SQLITE_CONFIG_SORTERREF_SIZE]]
                   2119: ** <dt>SQLITE_CONFIG_SORTERREF_SIZE
                   2120: ** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter
                   2121: ** of type (int) - the new value of the sorter-reference size threshold.
                   2122: ** Usually, when SQLite uses an external sort to order records according
                   2123: ** to an ORDER BY clause, all fields required by the caller are present in the
                   2124: ** sorted records. However, if SQLite determines based on the declared type
                   2125: ** of a table column that its values are likely to be very large - larger
                   2126: ** than the configured sorter-reference size threshold - then a reference
                   2127: ** is stored in each sorted record and the required column values loaded
                   2128: ** from the database as records are returned in sorted order. The default
                   2129: ** value for this option is to never use this optimization. Specifying a
                   2130: ** negative value for this option restores the default behaviour.
                   2131: ** This option is only available if SQLite is compiled with the
                   2132: ** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option.
                   2133: **
                   2134: ** [[SQLITE_CONFIG_MEMDB_MAXSIZE]]
                   2135: ** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE
                   2136: ** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter
                   2137: ** [sqlite3_int64] parameter which is the default maximum size for an in-memory
                   2138: ** database created using [sqlite3_deserialize()].  This default maximum
                   2139: ** size can be adjusted up or down for individual databases using the
                   2140: ** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control].  If this
                   2141: ** configuration setting is never used, then the default maximum is determined
                   2142: ** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option.  If that
                   2143: ** compile-time option is not set, then the default maximum is 1073741824.
1.3       misho    2144: ** </dl>
1.2       misho    2145: */
1.6.2.1 ! misho    2146: #define SQLITE_CONFIG_SINGLETHREAD         1  /* nil */
        !          2147: #define SQLITE_CONFIG_MULTITHREAD          2  /* nil */
        !          2148: #define SQLITE_CONFIG_SERIALIZED           3  /* nil */
        !          2149: #define SQLITE_CONFIG_MALLOC               4  /* sqlite3_mem_methods* */
        !          2150: #define SQLITE_CONFIG_GETMALLOC            5  /* sqlite3_mem_methods* */
        !          2151: #define SQLITE_CONFIG_SCRATCH              6  /* No longer used */
        !          2152: #define SQLITE_CONFIG_PAGECACHE            7  /* void*, int sz, int N */
        !          2153: #define SQLITE_CONFIG_HEAP                 8  /* void*, int nByte, int min */
        !          2154: #define SQLITE_CONFIG_MEMSTATUS            9  /* boolean */
        !          2155: #define SQLITE_CONFIG_MUTEX               10  /* sqlite3_mutex_methods* */
        !          2156: #define SQLITE_CONFIG_GETMUTEX            11  /* sqlite3_mutex_methods* */
        !          2157: /* previously SQLITE_CONFIG_CHUNKALLOC    12 which is now unused. */
        !          2158: #define SQLITE_CONFIG_LOOKASIDE           13  /* int int */
        !          2159: #define SQLITE_CONFIG_PCACHE              14  /* no-op */
        !          2160: #define SQLITE_CONFIG_GETPCACHE           15  /* no-op */
        !          2161: #define SQLITE_CONFIG_LOG                 16  /* xFunc, void* */
        !          2162: #define SQLITE_CONFIG_URI                 17  /* int */
        !          2163: #define SQLITE_CONFIG_PCACHE2             18  /* sqlite3_pcache_methods2* */
        !          2164: #define SQLITE_CONFIG_GETPCACHE2          19  /* sqlite3_pcache_methods2* */
1.3       misho    2165: #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
1.6.2.1 ! misho    2166: #define SQLITE_CONFIG_SQLLOG              21  /* xSqllog, void* */
        !          2167: #define SQLITE_CONFIG_MMAP_SIZE           22  /* sqlite3_int64, sqlite3_int64 */
1.4       misho    2168: #define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
                   2169: #define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
                   2170: #define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
                   2171: #define SQLITE_CONFIG_STMTJRNL_SPILL      26  /* int nByte */
1.5       misho    2172: #define SQLITE_CONFIG_SMALL_MALLOC        27  /* boolean */
                   2173: #define SQLITE_CONFIG_SORTERREF_SIZE      28  /* int nByte */
                   2174: #define SQLITE_CONFIG_MEMDB_MAXSIZE       29  /* sqlite3_int64 */
1.2       misho    2175: 
                   2176: /*
                   2177: ** CAPI3REF: Database Connection Configuration Options
                   2178: **
                   2179: ** These constants are the available integer configuration options that
                   2180: ** can be passed as the second argument to the [sqlite3_db_config()] interface.
                   2181: **
                   2182: ** New configuration options may be added in future releases of SQLite.
                   2183: ** Existing configuration options might be discontinued.  Applications
                   2184: ** should check the return code from [sqlite3_db_config()] to make sure that
                   2185: ** the call worked.  ^The [sqlite3_db_config()] interface will return a
                   2186: ** non-zero [error code] if a discontinued or unsupported configuration option
                   2187: ** is invoked.
                   2188: **
                   2189: ** <dl>
1.5       misho    2190: ** [[SQLITE_DBCONFIG_LOOKASIDE]]
1.2       misho    2191: ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
1.5       misho    2192: ** <dd> ^This option takes three additional arguments that determine the
1.2       misho    2193: ** [lookaside memory allocator] configuration for the [database connection].
                   2194: ** ^The first argument (the third parameter to [sqlite3_db_config()] is a
                   2195: ** pointer to a memory buffer to use for lookaside memory.
                   2196: ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
                   2197: ** may be NULL in which case SQLite will allocate the
                   2198: ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
                   2199: ** size of each lookaside buffer slot.  ^The third argument is the number of
                   2200: ** slots.  The size of the buffer in the first argument must be greater than
                   2201: ** or equal to the product of the second and third arguments.  The buffer
                   2202: ** must be aligned to an 8-byte boundary.  ^If the second argument to
                   2203: ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
                   2204: ** rounded down to the next smaller multiple of 8.  ^(The lookaside memory
                   2205: ** configuration for a database connection can only be changed when that
                   2206: ** connection is not currently using lookaside memory, or in other words
                   2207: ** when the "current value" returned by
1.6.2.1 ! misho    2208: ** [sqlite3_db_status](D,[SQLITE_DBSTATUS_LOOKASIDE_USED],...) is zero.
1.2       misho    2209: ** Any attempt to change the lookaside memory configuration when lookaside
1.5       misho    2210: ** memory is in use leaves the configuration unchanged and returns
1.2       misho    2211: ** [SQLITE_BUSY].)^</dd>
                   2212: **
1.5       misho    2213: ** [[SQLITE_DBCONFIG_ENABLE_FKEY]]
1.2       misho    2214: ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
                   2215: ** <dd> ^This option is used to enable or disable the enforcement of
                   2216: ** [foreign key constraints].  There should be two additional arguments.
                   2217: ** The first argument is an integer which is 0 to disable FK enforcement,
                   2218: ** positive to enable FK enforcement or negative to leave FK enforcement
                   2219: ** unchanged.  The second parameter is a pointer to an integer into which
                   2220: ** is written 0 or 1 to indicate whether FK enforcement is off or on
                   2221: ** following this call.  The second parameter may be a NULL pointer, in
                   2222: ** which case the FK enforcement setting is not reported back. </dd>
                   2223: **
1.5       misho    2224: ** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]]
1.2       misho    2225: ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
                   2226: ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
                   2227: ** There should be two additional arguments.
                   2228: ** The first argument is an integer which is 0 to disable triggers,
                   2229: ** positive to enable triggers or negative to leave the setting unchanged.
                   2230: ** The second parameter is a pointer to an integer into which
                   2231: ** is written 0 or 1 to indicate whether triggers are disabled or enabled
                   2232: ** following this call.  The second parameter may be a NULL pointer, in
1.6       misho    2233: ** which case the trigger setting is not reported back.
                   2234: **
                   2235: ** <p>Originally this option disabled all triggers.  ^(However, since
                   2236: ** SQLite version 3.35.0, TEMP triggers are still allowed even if
                   2237: ** this option is off.  So, in other words, this option now only disables
                   2238: ** triggers in the main database schema or in the schemas of ATTACH-ed
                   2239: ** databases.)^ </dd>
1.2       misho    2240: **
1.5       misho    2241: ** [[SQLITE_DBCONFIG_ENABLE_VIEW]]
                   2242: ** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt>
                   2243: ** <dd> ^This option is used to enable or disable [CREATE VIEW | views].
                   2244: ** There should be two additional arguments.
                   2245: ** The first argument is an integer which is 0 to disable views,
                   2246: ** positive to enable views or negative to leave the setting unchanged.
                   2247: ** The second parameter is a pointer to an integer into which
                   2248: ** is written 0 or 1 to indicate whether views are disabled or enabled
                   2249: ** following this call.  The second parameter may be a NULL pointer, in
1.6       misho    2250: ** which case the view setting is not reported back.
                   2251: **
                   2252: ** <p>Originally this option disabled all views.  ^(However, since
                   2253: ** SQLite version 3.35.0, TEMP views are still allowed even if
                   2254: ** this option is off.  So, in other words, this option now only disables
                   2255: ** views in the main database schema or in the schemas of ATTACH-ed
                   2256: ** databases.)^ </dd>
1.5       misho    2257: **
                   2258: ** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]]
1.4       misho    2259: ** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>
1.5       misho    2260: ** <dd> ^This option is used to enable or disable the
                   2261: ** [fts3_tokenizer()] function which is part of the
1.4       misho    2262: ** [FTS3] full-text search engine extension.
                   2263: ** There should be two additional arguments.
                   2264: ** The first argument is an integer which is 0 to disable fts3_tokenizer() or
                   2265: ** positive to enable fts3_tokenizer() or negative to leave the setting
                   2266: ** unchanged.
                   2267: ** The second parameter is a pointer to an integer into which
                   2268: ** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled
                   2269: ** following this call.  The second parameter may be a NULL pointer, in
                   2270: ** which case the new setting is not reported back. </dd>
                   2271: **
1.5       misho    2272: ** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]]
1.4       misho    2273: ** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>
                   2274: ** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]
                   2275: ** interface independently of the [load_extension()] SQL function.
                   2276: ** The [sqlite3_enable_load_extension()] API enables or disables both the
                   2277: ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].
                   2278: ** There should be two additional arguments.
                   2279: ** When the first argument to this interface is 1, then only the C-API is
                   2280: ** enabled and the SQL function remains disabled.  If the first argument to
                   2281: ** this interface is 0, then both the C-API and the SQL function are disabled.
                   2282: ** If the first argument is -1, then no changes are made to state of either the
                   2283: ** C-API or the SQL function.
                   2284: ** The second parameter is a pointer to an integer into which
                   2285: ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface
                   2286: ** is disabled or enabled following this call.  The second parameter may
                   2287: ** be a NULL pointer, in which case the new setting is not reported back.
                   2288: ** </dd>
                   2289: **
1.5       misho    2290: ** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>
                   2291: ** <dd> ^This option is used to change the name of the "main" database
                   2292: ** schema.  ^The sole argument is a pointer to a constant UTF8 string
                   2293: ** which will become the new schema name in place of "main".  ^SQLite
                   2294: ** does not make a copy of the new main schema name string, so the application
                   2295: ** must ensure that the argument passed into this DBCONFIG option is unchanged
                   2296: ** until after the database connection closes.
                   2297: ** </dd>
                   2298: **
                   2299: ** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]]
                   2300: ** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt>
                   2301: ** <dd> Usually, when a database in wal mode is closed or detached from a
                   2302: ** database handle, SQLite checks if this will mean that there are now no
                   2303: ** connections at all to the database. If so, it performs a checkpoint
                   2304: ** operation before closing the connection. This option may be used to
                   2305: ** override this behaviour. The first parameter passed to this operation
                   2306: ** is an integer - positive to disable checkpoints-on-close, or zero (the
                   2307: ** default) to enable them, and negative to leave the setting unchanged.
                   2308: ** The second parameter is a pointer to an integer
                   2309: ** into which is written 0 or 1 to indicate whether checkpoints-on-close
                   2310: ** have been disabled - 0 if they are not disabled, 1 if they are.
                   2311: ** </dd>
                   2312: **
                   2313: ** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt>
                   2314: ** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates
                   2315: ** the [query planner stability guarantee] (QPSG).  When the QPSG is active,
                   2316: ** a single SQL query statement will always use the same algorithm regardless
                   2317: ** of values of [bound parameters].)^ The QPSG disables some query optimizations
                   2318: ** that look at the values of bound parameters, which can make some queries
                   2319: ** slower.  But the QPSG has the advantage of more predictable behavior.  With
                   2320: ** the QPSG active, SQLite will always use the same query plan in the field as
                   2321: ** was used during testing in the lab.
                   2322: ** The first argument to this setting is an integer which is 0 to disable
                   2323: ** the QPSG, positive to enable QPSG, or negative to leave the setting
                   2324: ** unchanged. The second parameter is a pointer to an integer into which
                   2325: ** is written 0 or 1 to indicate whether the QPSG is disabled or enabled
                   2326: ** following this call.
                   2327: ** </dd>
                   2328: **
                   2329: ** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt>
                   2330: ** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not
                   2331: ** include output for any operations performed by trigger programs. This
                   2332: ** option is used to set or clear (the default) a flag that governs this
                   2333: ** behavior. The first parameter passed to this operation is an integer -
                   2334: ** positive to enable output for trigger programs, or zero to disable it,
                   2335: ** or negative to leave the setting unchanged.
                   2336: ** The second parameter is a pointer to an integer into which is written
                   2337: ** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if
                   2338: ** it is not disabled, 1 if it is.
                   2339: ** </dd>
                   2340: **
                   2341: ** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt>
                   2342: ** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run
                   2343: ** [VACUUM] in order to reset a database back to an empty database
                   2344: ** with no schema and no content. The following process works even for
                   2345: ** a badly corrupted database file:
                   2346: ** <ol>
                   2347: ** <li> If the database connection is newly opened, make sure it has read the
                   2348: **      database schema by preparing then discarding some query against the
                   2349: **      database, or calling sqlite3_table_column_metadata(), ignoring any
                   2350: **      errors.  This step is only necessary if the application desires to keep
                   2351: **      the database in WAL mode after the reset if it was in WAL mode before
                   2352: **      the reset.
                   2353: ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0);
                   2354: ** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0);
                   2355: ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0);
                   2356: ** </ol>
                   2357: ** Because resetting a database is destructive and irreversible, the
1.6.2.1 ! misho    2358: ** process requires the use of this obscure API and multiple steps to
        !          2359: ** help ensure that it does not happen by accident. Because this
        !          2360: ** feature must be capable of resetting corrupt databases, and
        !          2361: ** shutting down virtual tables may require access to that corrupt
        !          2362: ** storage, the library must abandon any installed virtual tables
        !          2363: ** without calling their xDestroy() methods.
1.5       misho    2364: **
                   2365: ** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt>
                   2366: ** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the
                   2367: ** "defensive" flag for a database connection.  When the defensive
                   2368: ** flag is enabled, language features that allow ordinary SQL to
                   2369: ** deliberately corrupt the database file are disabled.  The disabled
                   2370: ** features include but are not limited to the following:
                   2371: ** <ul>
                   2372: ** <li> The [PRAGMA writable_schema=ON] statement.
                   2373: ** <li> The [PRAGMA journal_mode=OFF] statement.
1.6.2.1 ! misho    2374: ** <li> The [PRAGMA schema_version=N] statement.
1.5       misho    2375: ** <li> Writes to the [sqlite_dbpage] virtual table.
                   2376: ** <li> Direct writes to [shadow tables].
                   2377: ** </ul>
                   2378: ** </dd>
                   2379: **
                   2380: ** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt>
                   2381: ** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the
                   2382: ** "writable_schema" flag. This has the same effect and is logically equivalent
                   2383: ** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF].
                   2384: ** The first argument to this setting is an integer which is 0 to disable
                   2385: ** the writable_schema, positive to enable writable_schema, or negative to
                   2386: ** leave the setting unchanged. The second parameter is a pointer to an
                   2387: ** integer into which is written 0 or 1 to indicate whether the writable_schema
                   2388: ** is enabled or disabled following this call.
                   2389: ** </dd>
                   2390: **
                   2391: ** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]]
                   2392: ** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt>
                   2393: ** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates
                   2394: ** the legacy behavior of the [ALTER TABLE RENAME] command such it
                   2395: ** behaves as it did prior to [version 3.24.0] (2018-06-04).  See the
                   2396: ** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for
                   2397: ** additional information. This feature can also be turned on and off
                   2398: ** using the [PRAGMA legacy_alter_table] statement.
                   2399: ** </dd>
                   2400: **
                   2401: ** [[SQLITE_DBCONFIG_DQS_DML]]
1.6.2.1 ! misho    2402: ** <dt>SQLITE_DBCONFIG_DQS_DML</dt>
1.5       misho    2403: ** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates
                   2404: ** the legacy [double-quoted string literal] misfeature for DML statements
                   2405: ** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The
                   2406: ** default value of this setting is determined by the [-DSQLITE_DQS]
                   2407: ** compile-time option.
                   2408: ** </dd>
                   2409: **
                   2410: ** [[SQLITE_DBCONFIG_DQS_DDL]]
1.6.2.1 ! misho    2411: ** <dt>SQLITE_DBCONFIG_DQS_DDL</dt>
1.5       misho    2412: ** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates
                   2413: ** the legacy [double-quoted string literal] misfeature for DDL statements,
                   2414: ** such as CREATE TABLE and CREATE INDEX. The
                   2415: ** default value of this setting is determined by the [-DSQLITE_DQS]
                   2416: ** compile-time option.
                   2417: ** </dd>
                   2418: **
                   2419: ** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]]
1.6.2.1 ! misho    2420: ** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</dt>
1.5       misho    2421: ** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to
                   2422: ** assume that database schemas are untainted by malicious content.
                   2423: ** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite
                   2424: ** takes additional defensive steps to protect the application from harm
                   2425: ** including:
                   2426: ** <ul>
                   2427: ** <li> Prohibit the use of SQL functions inside triggers, views,
                   2428: ** CHECK constraints, DEFAULT clauses, expression indexes,
                   2429: ** partial indexes, or generated columns
                   2430: ** unless those functions are tagged with [SQLITE_INNOCUOUS].
                   2431: ** <li> Prohibit the use of virtual tables inside of triggers or views
                   2432: ** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS].
                   2433: ** </ul>
                   2434: ** This setting defaults to "on" for legacy compatibility, however
                   2435: ** all applications are advised to turn it off if possible. This setting
                   2436: ** can also be controlled using the [PRAGMA trusted_schema] statement.
                   2437: ** </dd>
                   2438: **
                   2439: ** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]]
1.6.2.1 ! misho    2440: ** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</dt>
1.5       misho    2441: ** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates
                   2442: ** the legacy file format flag.  When activated, this flag causes all newly
                   2443: ** created database file to have a schema format version number (the 4-byte
                   2444: ** integer found at offset 44 into the database header) of 1.  This in turn
                   2445: ** means that the resulting database file will be readable and writable by
                   2446: ** any SQLite version back to 3.0.0 ([dateof:3.0.0]).  Without this setting,
                   2447: ** newly created databases are generally not understandable by SQLite versions
                   2448: ** prior to 3.3.0 ([dateof:3.3.0]).  As these words are written, there
1.6.2.1 ! misho    2449: ** is now scarcely any need to generate database files that are compatible
1.5       misho    2450: ** all the way back to version 3.0.0, and so this setting is of little
                   2451: ** practical use, but is provided so that SQLite can continue to claim the
                   2452: ** ability to generate new database files that are compatible with  version
                   2453: ** 3.0.0.
                   2454: ** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on,
                   2455: ** the [VACUUM] command will fail with an obscure error when attempting to
                   2456: ** process a table with generated columns and a descending index.  This is
                   2457: ** not considered a bug since SQLite versions 3.3.0 and earlier do not support
1.6.2.1 ! misho    2458: ** either generated columns or descending indexes.
        !          2459: ** </dd>
        !          2460: **
        !          2461: ** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]]
        !          2462: ** <dt>SQLITE_DBCONFIG_STMT_SCANSTATUS</dt>
        !          2463: ** <dd>The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in
        !          2464: ** SQLITE_ENABLE_STMT_SCANSTATUS builds. In this case, it sets or clears
        !          2465: ** a flag that enables collection of the sqlite3_stmt_scanstatus_v2()
        !          2466: ** statistics. For statistics to be collected, the flag must be set on
        !          2467: ** the database handle both when the SQL statement is prepared and when it
        !          2468: ** is stepped. The flag is set (collection of statistics is enabled)
        !          2469: ** by default.  This option takes two arguments: an integer and a pointer to
        !          2470: ** an integer..  The first argument is 1, 0, or -1 to enable, disable, or
        !          2471: ** leave unchanged the statement scanstatus option.  If the second argument
        !          2472: ** is not NULL, then the value of the statement scanstatus setting after
        !          2473: ** processing the first argument is written into the integer that the second
        !          2474: ** argument points to.
        !          2475: ** </dd>
        !          2476: **
        !          2477: ** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]]
        !          2478: ** <dt>SQLITE_DBCONFIG_REVERSE_SCANORDER</dt>
        !          2479: ** <dd>The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order
        !          2480: ** in which tables and indexes are scanned so that the scans start at the end
        !          2481: ** and work toward the beginning rather than starting at the beginning and
        !          2482: ** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the
        !          2483: ** same as setting [PRAGMA reverse_unordered_selects].  This option takes
        !          2484: ** two arguments which are an integer and a pointer to an integer.  The first
        !          2485: ** argument is 1, 0, or -1 to enable, disable, or leave unchanged the
        !          2486: ** reverse scan order flag, respectively.  If the second argument is not NULL,
        !          2487: ** then 0 or 1 is written into the integer that the second argument points to
        !          2488: ** depending on if the reverse scan order flag is set after processing the
        !          2489: ** first argument.
1.5       misho    2490: ** </dd>
1.6.2.1 ! misho    2491: **
1.2       misho    2492: ** </dl>
                   2493: */
1.5       misho    2494: #define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
1.4       misho    2495: #define SQLITE_DBCONFIG_LOOKASIDE             1001 /* void* int int */
                   2496: #define SQLITE_DBCONFIG_ENABLE_FKEY           1002 /* int int* */
                   2497: #define SQLITE_DBCONFIG_ENABLE_TRIGGER        1003 /* int int* */
                   2498: #define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */
                   2499: #define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */
1.5       misho    2500: #define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE      1006 /* int int* */
                   2501: #define SQLITE_DBCONFIG_ENABLE_QPSG           1007 /* int int* */
                   2502: #define SQLITE_DBCONFIG_TRIGGER_EQP           1008 /* int int* */
                   2503: #define SQLITE_DBCONFIG_RESET_DATABASE        1009 /* int int* */
                   2504: #define SQLITE_DBCONFIG_DEFENSIVE             1010 /* int int* */
                   2505: #define SQLITE_DBCONFIG_WRITABLE_SCHEMA       1011 /* int int* */
                   2506: #define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE    1012 /* int int* */
                   2507: #define SQLITE_DBCONFIG_DQS_DML               1013 /* int int* */
                   2508: #define SQLITE_DBCONFIG_DQS_DDL               1014 /* int int* */
                   2509: #define SQLITE_DBCONFIG_ENABLE_VIEW           1015 /* int int* */
                   2510: #define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT    1016 /* int int* */
                   2511: #define SQLITE_DBCONFIG_TRUSTED_SCHEMA        1017 /* int int* */
1.6.2.1 ! misho    2512: #define SQLITE_DBCONFIG_STMT_SCANSTATUS       1018 /* int int* */
        !          2513: #define SQLITE_DBCONFIG_REVERSE_SCANORDER     1019 /* int int* */
        !          2514: #define SQLITE_DBCONFIG_MAX                   1019 /* Largest DBCONFIG */
1.2       misho    2515: 
                   2516: /*
                   2517: ** CAPI3REF: Enable Or Disable Extended Result Codes
1.4       misho    2518: ** METHOD: sqlite3
1.2       misho    2519: **
                   2520: ** ^The sqlite3_extended_result_codes() routine enables or disables the
                   2521: ** [extended result codes] feature of SQLite. ^The extended result
                   2522: ** codes are disabled by default for historical compatibility.
                   2523: */
                   2524: SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
                   2525: 
                   2526: /*
                   2527: ** CAPI3REF: Last Insert Rowid
1.4       misho    2528: ** METHOD: sqlite3
1.2       misho    2529: **
1.4       misho    2530: ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)
                   2531: ** has a unique 64-bit signed
1.2       misho    2532: ** integer key called the [ROWID | "rowid"]. ^The rowid is always available
                   2533: ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
                   2534: ** names are not also used by explicitly declared columns. ^If
                   2535: ** the table has a column of type [INTEGER PRIMARY KEY] then that column
                   2536: ** is another alias for the rowid.
                   2537: **
1.5       misho    2538: ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of
                   2539: ** the most recent successful [INSERT] into a rowid table or [virtual table]
                   2540: ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not
                   2541: ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred
                   2542: ** on the database connection D, then sqlite3_last_insert_rowid(D) returns
                   2543: ** zero.
                   2544: **
                   2545: ** As well as being set automatically as rows are inserted into database
                   2546: ** tables, the value returned by this function may be set explicitly by
                   2547: ** [sqlite3_set_last_insert_rowid()]
                   2548: **
                   2549: ** Some virtual table implementations may INSERT rows into rowid tables as
                   2550: ** part of committing a transaction (e.g. to flush data accumulated in memory
                   2551: ** to disk). In this case subsequent calls to this function return the rowid
                   2552: ** associated with these internal INSERT operations, which leads to
                   2553: ** unintuitive results. Virtual table implementations that do write to rowid
                   2554: ** tables in this way can avoid this problem by restoring the original
                   2555: ** rowid value using [sqlite3_set_last_insert_rowid()] before returning
                   2556: ** control to the user.
                   2557: **
                   2558: ** ^(If an [INSERT] occurs within a trigger then this routine will
                   2559: ** return the [rowid] of the inserted row as long as the trigger is
                   2560: ** running. Once the trigger program ends, the value returned
                   2561: ** by this routine reverts to what it was before the trigger was fired.)^
1.2       misho    2562: **
                   2563: ** ^An [INSERT] that fails due to a constraint violation is not a
                   2564: ** successful [INSERT] and does not change the value returned by this
                   2565: ** routine.  ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
                   2566: ** and INSERT OR ABORT make no changes to the return value of this
                   2567: ** routine when their insertion fails.  ^(When INSERT OR REPLACE
                   2568: ** encounters a constraint violation, it does not fail.  The
                   2569: ** INSERT continues to completion after deleting rows that caused
                   2570: ** the constraint problem so INSERT OR REPLACE will always change
                   2571: ** the return value of this interface.)^
                   2572: **
                   2573: ** ^For the purposes of this routine, an [INSERT] is considered to
                   2574: ** be successful even if it is subsequently rolled back.
                   2575: **
                   2576: ** This function is accessible to SQL statements via the
                   2577: ** [last_insert_rowid() SQL function].
                   2578: **
                   2579: ** If a separate thread performs a new [INSERT] on the same
                   2580: ** database connection while the [sqlite3_last_insert_rowid()]
                   2581: ** function is running and thus changes the last insert [rowid],
                   2582: ** then the value returned by [sqlite3_last_insert_rowid()] is
                   2583: ** unpredictable and might not equal either the old or the new
                   2584: ** last insert [rowid].
                   2585: */
                   2586: SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
                   2587: 
                   2588: /*
1.5       misho    2589: ** CAPI3REF: Set the Last Insert Rowid value.
                   2590: ** METHOD: sqlite3
                   2591: **
                   2592: ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to
                   2593: ** set the value returned by calling sqlite3_last_insert_rowid(D) to R
                   2594: ** without inserting a row into the database.
                   2595: */
                   2596: SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64);
                   2597: 
                   2598: /*
1.2       misho    2599: ** CAPI3REF: Count The Number Of Rows Modified
1.4       misho    2600: ** METHOD: sqlite3
1.2       misho    2601: **
1.6.2.1 ! misho    2602: ** ^These functions return the number of rows modified, inserted or
1.4       misho    2603: ** deleted by the most recently completed INSERT, UPDATE or DELETE
                   2604: ** statement on the database connection specified by the only parameter.
1.6.2.1 ! misho    2605: ** The two functions are identical except for the type of the return value
        !          2606: ** and that if the number of rows modified by the most recent INSERT, UPDATE
        !          2607: ** or DELETE is greater than the maximum value supported by type "int", then
        !          2608: ** the return value of sqlite3_changes() is undefined. ^Executing any other
        !          2609: ** type of SQL statement does not modify the value returned by these functions.
1.4       misho    2610: **
                   2611: ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are
1.5       misho    2612: ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers],
1.4       misho    2613: ** [foreign key actions] or [REPLACE] constraint resolution are not counted.
1.5       misho    2614: **
                   2615: ** Changes to a view that are intercepted by
                   2616: ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value
                   2617: ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or
                   2618: ** DELETE statement run on a view is always zero. Only changes made to real
1.4       misho    2619: ** tables are counted.
                   2620: **
                   2621: ** Things are more complicated if the sqlite3_changes() function is
                   2622: ** executed while a trigger program is running. This may happen if the
                   2623: ** program uses the [changes() SQL function], or if some other callback
                   2624: ** function invokes sqlite3_changes() directly. Essentially:
1.5       misho    2625: **
1.4       misho    2626: ** <ul>
                   2627: **   <li> ^(Before entering a trigger program the value returned by
1.5       misho    2628: **        sqlite3_changes() function is saved. After the trigger program
1.4       misho    2629: **        has finished, the original value is restored.)^
1.5       misho    2630: **
                   2631: **   <li> ^(Within a trigger program each INSERT, UPDATE and DELETE
                   2632: **        statement sets the value returned by sqlite3_changes()
                   2633: **        upon completion as normal. Of course, this value will not include
                   2634: **        any changes performed by sub-triggers, as the sqlite3_changes()
1.4       misho    2635: **        value will be saved and restored after each sub-trigger has run.)^
                   2636: ** </ul>
1.5       misho    2637: **
1.4       misho    2638: ** ^This means that if the changes() SQL function (or similar) is used
1.5       misho    2639: ** by the first INSERT, UPDATE or DELETE statement within a trigger, it
1.4       misho    2640: ** returns the value as set when the calling statement began executing.
1.5       misho    2641: ** ^If it is used by the second or subsequent such statement within a trigger
                   2642: ** program, the value returned reflects the number of rows modified by the
1.4       misho    2643: ** previous INSERT, UPDATE or DELETE statement within the same trigger.
1.2       misho    2644: **
                   2645: ** If a separate thread makes changes on the same database connection
                   2646: ** while [sqlite3_changes()] is running then the value returned
                   2647: ** is unpredictable and not meaningful.
1.5       misho    2648: **
                   2649: ** See also:
                   2650: ** <ul>
                   2651: ** <li> the [sqlite3_total_changes()] interface
                   2652: ** <li> the [count_changes pragma]
                   2653: ** <li> the [changes() SQL function]
                   2654: ** <li> the [data_version pragma]
                   2655: ** </ul>
1.2       misho    2656: */
                   2657: SQLITE_API int sqlite3_changes(sqlite3*);
1.6.2.1 ! misho    2658: SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*);
1.2       misho    2659: 
                   2660: /*
                   2661: ** CAPI3REF: Total Number Of Rows Modified
1.4       misho    2662: ** METHOD: sqlite3
1.2       misho    2663: **
1.6.2.1 ! misho    2664: ** ^These functions return the total number of rows inserted, modified or
1.4       misho    2665: ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed
                   2666: ** since the database connection was opened, including those executed as
1.6.2.1 ! misho    2667: ** part of trigger programs. The two functions are identical except for the
        !          2668: ** type of the return value and that if the number of rows modified by the
        !          2669: ** connection exceeds the maximum value supported by type "int", then
        !          2670: ** the return value of sqlite3_total_changes() is undefined. ^Executing
        !          2671: ** any other type of SQL statement does not affect the value returned by
        !          2672: ** sqlite3_total_changes().
1.5       misho    2673: **
1.4       misho    2674: ** ^Changes made as part of [foreign key actions] are included in the
                   2675: ** count, but those made as part of REPLACE constraint resolution are
1.5       misho    2676: ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers
1.4       misho    2677: ** are not counted.
1.5       misho    2678: **
                   2679: ** The [sqlite3_total_changes(D)] interface only reports the number
                   2680: ** of rows that changed due to SQL statement run against database
                   2681: ** connection D.  Any changes by other database connections are ignored.
                   2682: ** To detect changes against a database file from other database
                   2683: ** connections use the [PRAGMA data_version] command or the
                   2684: ** [SQLITE_FCNTL_DATA_VERSION] [file control].
1.2       misho    2685: **
                   2686: ** If a separate thread makes changes on the same database connection
                   2687: ** while [sqlite3_total_changes()] is running then the value
                   2688: ** returned is unpredictable and not meaningful.
1.5       misho    2689: **
                   2690: ** See also:
                   2691: ** <ul>
                   2692: ** <li> the [sqlite3_changes()] interface
                   2693: ** <li> the [count_changes pragma]
                   2694: ** <li> the [changes() SQL function]
                   2695: ** <li> the [data_version pragma]
                   2696: ** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control]
                   2697: ** </ul>
1.2       misho    2698: */
                   2699: SQLITE_API int sqlite3_total_changes(sqlite3*);
1.6.2.1 ! misho    2700: SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*);
1.2       misho    2701: 
                   2702: /*
                   2703: ** CAPI3REF: Interrupt A Long-Running Query
1.4       misho    2704: ** METHOD: sqlite3
1.2       misho    2705: **
                   2706: ** ^This function causes any pending database operation to abort and
                   2707: ** return at its earliest opportunity. This routine is typically
                   2708: ** called in response to a user action such as pressing "Cancel"
                   2709: ** or Ctrl-C where the user wants a long query operation to halt
                   2710: ** immediately.
                   2711: **
                   2712: ** ^It is safe to call this routine from a thread different from the
                   2713: ** thread that is currently running the database operation.  But it
                   2714: ** is not safe to call this routine with a [database connection] that
                   2715: ** is closed or might close before sqlite3_interrupt() returns.
                   2716: **
                   2717: ** ^If an SQL operation is very nearly finished at the time when
                   2718: ** sqlite3_interrupt() is called, then it might not have an opportunity
                   2719: ** to be interrupted and might continue to completion.
                   2720: **
                   2721: ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
                   2722: ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
                   2723: ** that is inside an explicit transaction, then the entire transaction
                   2724: ** will be rolled back automatically.
                   2725: **
                   2726: ** ^The sqlite3_interrupt(D) call is in effect until all currently running
                   2727: ** SQL statements on [database connection] D complete.  ^Any new SQL statements
1.5       misho    2728: ** that are started after the sqlite3_interrupt() call and before the
                   2729: ** running statement count reaches zero are interrupted as if they had been
1.2       misho    2730: ** running prior to the sqlite3_interrupt() call.  ^New SQL statements
                   2731: ** that are started after the running statement count reaches zero are
                   2732: ** not effected by the sqlite3_interrupt().
                   2733: ** ^A call to sqlite3_interrupt(D) that occurs when there are no running
                   2734: ** SQL statements is a no-op and has no effect on SQL statements
                   2735: ** that are started after the sqlite3_interrupt() call returns.
1.6.2.1 ! misho    2736: **
        !          2737: ** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether
        !          2738: ** or not an interrupt is currently in effect for [database connection] D.
        !          2739: ** It returns 1 if an interrupt is currently in effect, or 0 otherwise.
1.2       misho    2740: */
                   2741: SQLITE_API void sqlite3_interrupt(sqlite3*);
1.6.2.1 ! misho    2742: SQLITE_API int sqlite3_is_interrupted(sqlite3*);
1.2       misho    2743: 
                   2744: /*
                   2745: ** CAPI3REF: Determine If An SQL Statement Is Complete
                   2746: **
                   2747: ** These routines are useful during command-line input to determine if the
                   2748: ** currently entered text seems to form a complete SQL statement or
                   2749: ** if additional input is needed before sending the text into
                   2750: ** SQLite for parsing.  ^These routines return 1 if the input string
                   2751: ** appears to be a complete SQL statement.  ^A statement is judged to be
                   2752: ** complete if it ends with a semicolon token and is not a prefix of a
                   2753: ** well-formed CREATE TRIGGER statement.  ^Semicolons that are embedded within
                   2754: ** string literals or quoted identifier names or comments are not
                   2755: ** independent tokens (they are part of the token in which they are
                   2756: ** embedded) and thus do not count as a statement terminator.  ^Whitespace
                   2757: ** and comments that follow the final semicolon are ignored.
                   2758: **
                   2759: ** ^These routines return 0 if the statement is incomplete.  ^If a
                   2760: ** memory allocation fails, then SQLITE_NOMEM is returned.
                   2761: **
                   2762: ** ^These routines do not parse the SQL statements thus
                   2763: ** will not detect syntactically incorrect SQL.
                   2764: **
1.5       misho    2765: ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
1.2       misho    2766: ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
                   2767: ** automatically by sqlite3_complete16().  If that initialization fails,
                   2768: ** then the return value from sqlite3_complete16() will be non-zero
                   2769: ** regardless of whether or not the input SQL is complete.)^
                   2770: **
                   2771: ** The input to [sqlite3_complete()] must be a zero-terminated
                   2772: ** UTF-8 string.
                   2773: **
                   2774: ** The input to [sqlite3_complete16()] must be a zero-terminated
                   2775: ** UTF-16 string in native byte order.
                   2776: */
                   2777: SQLITE_API int sqlite3_complete(const char *sql);
                   2778: SQLITE_API int sqlite3_complete16(const void *sql);
                   2779: 
                   2780: /*
                   2781: ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
1.4       misho    2782: ** KEYWORDS: {busy-handler callback} {busy handler}
                   2783: ** METHOD: sqlite3
1.2       misho    2784: **
1.4       misho    2785: ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X
                   2786: ** that might be invoked with argument P whenever
                   2787: ** an attempt is made to access a database table associated with
                   2788: ** [database connection] D when another thread
                   2789: ** or process has the table locked.
                   2790: ** The sqlite3_busy_handler() interface is used to implement
                   2791: ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].
1.2       misho    2792: **
1.4       misho    2793: ** ^If the busy callback is NULL, then [SQLITE_BUSY]
1.2       misho    2794: ** is returned immediately upon encountering the lock.  ^If the busy callback
                   2795: ** is not NULL, then the callback might be invoked with two arguments.
                   2796: **
                   2797: ** ^The first argument to the busy handler is a copy of the void* pointer which
                   2798: ** is the third argument to sqlite3_busy_handler().  ^The second argument to
                   2799: ** the busy handler callback is the number of times that the busy handler has
1.4       misho    2800: ** been invoked previously for the same locking event.  ^If the
1.2       misho    2801: ** busy callback returns 0, then no additional attempts are made to
1.4       misho    2802: ** access the database and [SQLITE_BUSY] is returned
                   2803: ** to the application.
1.2       misho    2804: ** ^If the callback returns non-zero, then another attempt
1.4       misho    2805: ** is made to access the database and the cycle repeats.
1.2       misho    2806: **
                   2807: ** The presence of a busy handler does not guarantee that it will be invoked
                   2808: ** when there is lock contention. ^If SQLite determines that invoking the busy
                   2809: ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
1.5       misho    2810: ** to the application instead of invoking the
1.4       misho    2811: ** busy handler.
1.2       misho    2812: ** Consider a scenario where one process is holding a read lock that
                   2813: ** it is trying to promote to a reserved lock and
                   2814: ** a second process is holding a reserved lock that it is trying
                   2815: ** to promote to an exclusive lock.  The first process cannot proceed
                   2816: ** because it is blocked by the second and the second process cannot
                   2817: ** proceed because it is blocked by the first.  If both processes
                   2818: ** invoke the busy handlers, neither will make any progress.  Therefore,
                   2819: ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
                   2820: ** will induce the first process to release its read lock and allow
                   2821: ** the second process to proceed.
                   2822: **
                   2823: ** ^The default busy callback is NULL.
                   2824: **
                   2825: ** ^(There can only be a single busy handler defined for each
                   2826: ** [database connection].  Setting a new busy handler clears any
                   2827: ** previously set handler.)^  ^Note that calling [sqlite3_busy_timeout()]
1.4       misho    2828: ** or evaluating [PRAGMA busy_timeout=N] will change the
                   2829: ** busy handler and thus clear any previously set busy handler.
1.2       misho    2830: **
                   2831: ** The busy callback should not take any actions which modify the
1.4       misho    2832: ** database connection that invoked the busy handler.  In other words,
                   2833: ** the busy handler is not reentrant.  Any such actions
1.2       misho    2834: ** result in undefined behavior.
1.5       misho    2835: **
1.2       misho    2836: ** A busy handler must not close the database connection
                   2837: ** or [prepared statement] that invoked the busy handler.
                   2838: */
1.4       misho    2839: SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);
1.2       misho    2840: 
                   2841: /*
                   2842: ** CAPI3REF: Set A Busy Timeout
1.4       misho    2843: ** METHOD: sqlite3
1.2       misho    2844: **
                   2845: ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
                   2846: ** for a specified amount of time when a table is locked.  ^The handler
                   2847: ** will sleep multiple times until at least "ms" milliseconds of sleeping
                   2848: ** have accumulated.  ^After at least "ms" milliseconds of sleeping,
                   2849: ** the handler returns 0 which causes [sqlite3_step()] to return
1.4       misho    2850: ** [SQLITE_BUSY].
1.2       misho    2851: **
                   2852: ** ^Calling this routine with an argument less than or equal to zero
                   2853: ** turns off all busy handlers.
                   2854: **
                   2855: ** ^(There can only be a single busy handler for a particular
1.4       misho    2856: ** [database connection] at any given moment.  If another busy handler
1.2       misho    2857: ** was defined  (using [sqlite3_busy_handler()]) prior to calling
                   2858: ** this routine, that other busy handler is cleared.)^
1.4       misho    2859: **
                   2860: ** See also:  [PRAGMA busy_timeout]
1.2       misho    2861: */
                   2862: SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
                   2863: 
                   2864: /*
                   2865: ** CAPI3REF: Convenience Routines For Running Queries
1.4       misho    2866: ** METHOD: sqlite3
1.2       misho    2867: **
                   2868: ** This is a legacy interface that is preserved for backwards compatibility.
                   2869: ** Use of this interface is not recommended.
                   2870: **
                   2871: ** Definition: A <b>result table</b> is memory data structure created by the
                   2872: ** [sqlite3_get_table()] interface.  A result table records the
                   2873: ** complete query results from one or more queries.
                   2874: **
                   2875: ** The table conceptually has a number of rows and columns.  But
                   2876: ** these numbers are not part of the result table itself.  These
                   2877: ** numbers are obtained separately.  Let N be the number of rows
                   2878: ** and M be the number of columns.
                   2879: **
                   2880: ** A result table is an array of pointers to zero-terminated UTF-8 strings.
                   2881: ** There are (N+1)*M elements in the array.  The first M pointers point
                   2882: ** to zero-terminated strings that  contain the names of the columns.
                   2883: ** The remaining entries all point to query results.  NULL values result
                   2884: ** in NULL pointers.  All other values are in their UTF-8 zero-terminated
                   2885: ** string representation as returned by [sqlite3_column_text()].
                   2886: **
                   2887: ** A result table might consist of one or more memory allocations.
                   2888: ** It is not safe to pass a result table directly to [sqlite3_free()].
                   2889: ** A result table should be deallocated using [sqlite3_free_table()].
                   2890: **
                   2891: ** ^(As an example of the result table format, suppose a query result
                   2892: ** is as follows:
                   2893: **
                   2894: ** <blockquote><pre>
                   2895: **        Name        | Age
                   2896: **        -----------------------
                   2897: **        Alice       | 43
                   2898: **        Bob         | 28
                   2899: **        Cindy       | 21
                   2900: ** </pre></blockquote>
                   2901: **
1.5       misho    2902: ** There are two columns (M==2) and three rows (N==3).  Thus the
1.2       misho    2903: ** result table has 8 entries.  Suppose the result table is stored
1.5       misho    2904: ** in an array named azResult.  Then azResult holds this content:
1.2       misho    2905: **
                   2906: ** <blockquote><pre>
                   2907: **        azResult&#91;0] = "Name";
                   2908: **        azResult&#91;1] = "Age";
                   2909: **        azResult&#91;2] = "Alice";
                   2910: **        azResult&#91;3] = "43";
                   2911: **        azResult&#91;4] = "Bob";
                   2912: **        azResult&#91;5] = "28";
                   2913: **        azResult&#91;6] = "Cindy";
                   2914: **        azResult&#91;7] = "21";
                   2915: ** </pre></blockquote>)^
                   2916: **
                   2917: ** ^The sqlite3_get_table() function evaluates one or more
                   2918: ** semicolon-separated SQL statements in the zero-terminated UTF-8
                   2919: ** string of its 2nd parameter and returns a result table to the
                   2920: ** pointer given in its 3rd parameter.
                   2921: **
                   2922: ** After the application has finished with the result from sqlite3_get_table(),
                   2923: ** it must pass the result table pointer to sqlite3_free_table() in order to
                   2924: ** release the memory that was malloced.  Because of the way the
                   2925: ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
                   2926: ** function must not try to call [sqlite3_free()] directly.  Only
                   2927: ** [sqlite3_free_table()] is able to release the memory properly and safely.
                   2928: **
                   2929: ** The sqlite3_get_table() interface is implemented as a wrapper around
                   2930: ** [sqlite3_exec()].  The sqlite3_get_table() routine does not have access
                   2931: ** to any internal data structures of SQLite.  It uses only the public
                   2932: ** interface defined here.  As a consequence, errors that occur in the
                   2933: ** wrapper layer outside of the internal [sqlite3_exec()] call are not
                   2934: ** reflected in subsequent calls to [sqlite3_errcode()] or
                   2935: ** [sqlite3_errmsg()].
                   2936: */
                   2937: SQLITE_API int sqlite3_get_table(
                   2938:   sqlite3 *db,          /* An open database */
                   2939:   const char *zSql,     /* SQL to be evaluated */
                   2940:   char ***pazResult,    /* Results of the query */
                   2941:   int *pnRow,           /* Number of result rows written here */
                   2942:   int *pnColumn,        /* Number of result columns written here */
                   2943:   char **pzErrmsg       /* Error msg written here */
                   2944: );
                   2945: SQLITE_API void sqlite3_free_table(char **result);
                   2946: 
                   2947: /*
                   2948: ** CAPI3REF: Formatted String Printing Functions
                   2949: **
                   2950: ** These routines are work-alikes of the "printf()" family of functions
                   2951: ** from the standard C library.
1.5       misho    2952: ** These routines understand most of the common formatting options from
                   2953: ** the standard library printf()
                   2954: ** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]).
                   2955: ** See the [built-in printf()] documentation for details.
1.2       misho    2956: **
                   2957: ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
1.5       misho    2958: ** results into memory obtained from [sqlite3_malloc64()].
1.2       misho    2959: ** The strings returned by these two routines should be
                   2960: ** released by [sqlite3_free()].  ^Both routines return a
1.5       misho    2961: ** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough
1.2       misho    2962: ** memory to hold the resulting string.
                   2963: **
                   2964: ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
                   2965: ** the standard C library.  The result is written into the
                   2966: ** buffer supplied as the second parameter whose size is given by
                   2967: ** the first parameter. Note that the order of the
                   2968: ** first two parameters is reversed from snprintf().)^  This is an
                   2969: ** historical accident that cannot be fixed without breaking
                   2970: ** backwards compatibility.  ^(Note also that sqlite3_snprintf()
                   2971: ** returns a pointer to its buffer instead of the number of
                   2972: ** characters actually written into the buffer.)^  We admit that
                   2973: ** the number of characters written would be a more useful return
                   2974: ** value but we cannot change the implementation of sqlite3_snprintf()
                   2975: ** now without breaking compatibility.
                   2976: **
                   2977: ** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
                   2978: ** guarantees that the buffer is always zero-terminated.  ^The first
                   2979: ** parameter "n" is the total size of the buffer, including space for
                   2980: ** the zero terminator.  So the longest string that can be completely
                   2981: ** written will be n-1 characters.
                   2982: **
                   2983: ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
                   2984: **
1.5       misho    2985: ** See also:  [built-in printf()], [printf() SQL function]
1.2       misho    2986: */
                   2987: SQLITE_API char *sqlite3_mprintf(const char*,...);
                   2988: SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
                   2989: SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
                   2990: SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
                   2991: 
                   2992: /*
                   2993: ** CAPI3REF: Memory Allocation Subsystem
                   2994: **
                   2995: ** The SQLite core uses these three routines for all of its own
                   2996: ** internal memory allocation needs. "Core" in the previous sentence
1.5       misho    2997: ** does not include operating-system specific [VFS] implementation.  The
1.2       misho    2998: ** Windows VFS uses native malloc() and free() for some operations.
                   2999: **
                   3000: ** ^The sqlite3_malloc() routine returns a pointer to a block
                   3001: ** of memory at least N bytes in length, where N is the parameter.
                   3002: ** ^If sqlite3_malloc() is unable to obtain sufficient free
                   3003: ** memory, it returns a NULL pointer.  ^If the parameter N to
                   3004: ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
                   3005: ** a NULL pointer.
                   3006: **
1.4       misho    3007: ** ^The sqlite3_malloc64(N) routine works just like
                   3008: ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead
                   3009: ** of a signed 32-bit integer.
                   3010: **
1.2       misho    3011: ** ^Calling sqlite3_free() with a pointer previously returned
                   3012: ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
                   3013: ** that it might be reused.  ^The sqlite3_free() routine is
                   3014: ** a no-op if is called with a NULL pointer.  Passing a NULL pointer
                   3015: ** to sqlite3_free() is harmless.  After being freed, memory
                   3016: ** should neither be read nor written.  Even reading previously freed
                   3017: ** memory might result in a segmentation fault or other severe error.
                   3018: ** Memory corruption, a segmentation fault, or other severe error
                   3019: ** might result if sqlite3_free() is called with a non-NULL pointer that
                   3020: ** was not obtained from sqlite3_malloc() or sqlite3_realloc().
                   3021: **
1.4       misho    3022: ** ^The sqlite3_realloc(X,N) interface attempts to resize a
                   3023: ** prior memory allocation X to be at least N bytes.
                   3024: ** ^If the X parameter to sqlite3_realloc(X,N)
1.2       misho    3025: ** is a NULL pointer then its behavior is identical to calling
1.4       misho    3026: ** sqlite3_malloc(N).
                   3027: ** ^If the N parameter to sqlite3_realloc(X,N) is zero or
1.2       misho    3028: ** negative then the behavior is exactly the same as calling
1.4       misho    3029: ** sqlite3_free(X).
                   3030: ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation
                   3031: ** of at least N bytes in size or NULL if insufficient memory is available.
1.2       misho    3032: ** ^If M is the size of the prior allocation, then min(N,M) bytes
                   3033: ** of the prior allocation are copied into the beginning of buffer returned
1.4       misho    3034: ** by sqlite3_realloc(X,N) and the prior allocation is freed.
                   3035: ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the
                   3036: ** prior allocation is not freed.
                   3037: **
                   3038: ** ^The sqlite3_realloc64(X,N) interfaces works the same as
                   3039: ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead
                   3040: ** of a 32-bit signed integer.
                   3041: **
                   3042: ** ^If X is a memory allocation previously obtained from sqlite3_malloc(),
                   3043: ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then
                   3044: ** sqlite3_msize(X) returns the size of that memory allocation in bytes.
                   3045: ** ^The value returned by sqlite3_msize(X) might be larger than the number
                   3046: ** of bytes requested when X was allocated.  ^If X is a NULL pointer then
                   3047: ** sqlite3_msize(X) returns zero.  If X points to something that is not
                   3048: ** the beginning of memory allocation, or if it points to a formerly
                   3049: ** valid memory allocation that has now been freed, then the behavior
                   3050: ** of sqlite3_msize(X) is undefined and possibly harmful.
1.2       misho    3051: **
1.4       misho    3052: ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),
                   3053: ** sqlite3_malloc64(), and sqlite3_realloc64()
1.2       misho    3054: ** is always aligned to at least an 8 byte boundary, or to a
                   3055: ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
                   3056: ** option is used.
                   3057: **
                   3058: ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
                   3059: ** must be either NULL or else pointers obtained from a prior
                   3060: ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
                   3061: ** not yet been released.
                   3062: **
                   3063: ** The application must not read or write any part of
                   3064: ** a block of memory after it has been released using
                   3065: ** [sqlite3_free()] or [sqlite3_realloc()].
                   3066: */
                   3067: SQLITE_API void *sqlite3_malloc(int);
1.4       misho    3068: SQLITE_API void *sqlite3_malloc64(sqlite3_uint64);
1.2       misho    3069: SQLITE_API void *sqlite3_realloc(void*, int);
1.4       misho    3070: SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64);
1.2       misho    3071: SQLITE_API void sqlite3_free(void*);
1.4       misho    3072: SQLITE_API sqlite3_uint64 sqlite3_msize(void*);
1.2       misho    3073: 
                   3074: /*
                   3075: ** CAPI3REF: Memory Allocator Statistics
                   3076: **
                   3077: ** SQLite provides these two interfaces for reporting on the status
                   3078: ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
                   3079: ** routines, which form the built-in memory allocation subsystem.
                   3080: **
                   3081: ** ^The [sqlite3_memory_used()] routine returns the number of bytes
                   3082: ** of memory currently outstanding (malloced but not freed).
                   3083: ** ^The [sqlite3_memory_highwater()] routine returns the maximum
                   3084: ** value of [sqlite3_memory_used()] since the high-water mark
                   3085: ** was last reset.  ^The values returned by [sqlite3_memory_used()] and
                   3086: ** [sqlite3_memory_highwater()] include any overhead
                   3087: ** added by SQLite in its implementation of [sqlite3_malloc()],
                   3088: ** but not overhead added by the any underlying system library
                   3089: ** routines that [sqlite3_malloc()] may call.
                   3090: **
                   3091: ** ^The memory high-water mark is reset to the current value of
                   3092: ** [sqlite3_memory_used()] if and only if the parameter to
                   3093: ** [sqlite3_memory_highwater()] is true.  ^The value returned
                   3094: ** by [sqlite3_memory_highwater(1)] is the high-water mark
                   3095: ** prior to the reset.
                   3096: */
                   3097: SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
                   3098: SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
                   3099: 
                   3100: /*
                   3101: ** CAPI3REF: Pseudo-Random Number Generator
                   3102: **
                   3103: ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
                   3104: ** select random [ROWID | ROWIDs] when inserting new records into a table that
                   3105: ** already uses the largest possible [ROWID].  The PRNG is also used for
1.5       misho    3106: ** the built-in random() and randomblob() SQL functions.  This interface allows
1.2       misho    3107: ** applications to access the same PRNG for other purposes.
                   3108: **
                   3109: ** ^A call to this routine stores N bytes of randomness into buffer P.
1.4       misho    3110: ** ^The P parameter can be a NULL pointer.
1.2       misho    3111: **
1.4       misho    3112: ** ^If this routine has not been previously called or if the previous
                   3113: ** call had N less than one or a NULL pointer for P, then the PRNG is
                   3114: ** seeded using randomness obtained from the xRandomness method of
                   3115: ** the default [sqlite3_vfs] object.
                   3116: ** ^If the previous call to this routine had an N of 1 or more and a
                   3117: ** non-NULL P then the pseudo-randomness is generated
1.2       misho    3118: ** internally and without recourse to the [sqlite3_vfs] xRandomness
                   3119: ** method.
                   3120: */
                   3121: SQLITE_API void sqlite3_randomness(int N, void *P);
                   3122: 
                   3123: /*
                   3124: ** CAPI3REF: Compile-Time Authorization Callbacks
1.4       misho    3125: ** METHOD: sqlite3
1.5       misho    3126: ** KEYWORDS: {authorizer callback}
1.2       misho    3127: **
                   3128: ** ^This routine registers an authorizer callback with a particular
                   3129: ** [database connection], supplied in the first argument.
                   3130: ** ^The authorizer callback is invoked as SQL statements are being compiled
                   3131: ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
1.5       misho    3132: ** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()],
                   3133: ** and [sqlite3_prepare16_v3()].  ^At various
1.2       misho    3134: ** points during the compilation process, as logic is being created
                   3135: ** to perform various actions, the authorizer callback is invoked to
                   3136: ** see if those actions are allowed.  ^The authorizer callback should
                   3137: ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
                   3138: ** specific action but allow the SQL statement to continue to be
                   3139: ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
                   3140: ** rejected with an error.  ^If the authorizer callback returns
                   3141: ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
                   3142: ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
                   3143: ** the authorizer will fail with an error message.
                   3144: **
                   3145: ** When the callback returns [SQLITE_OK], that means the operation
                   3146: ** requested is ok.  ^When the callback returns [SQLITE_DENY], the
                   3147: ** [sqlite3_prepare_v2()] or equivalent call that triggered the
                   3148: ** authorizer will fail with an error message explaining that
1.5       misho    3149: ** access is denied.
1.2       misho    3150: **
                   3151: ** ^The first parameter to the authorizer callback is a copy of the third
                   3152: ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
                   3153: ** to the callback is an integer [SQLITE_COPY | action code] that specifies
                   3154: ** the particular action to be authorized. ^The third through sixth parameters
1.5       misho    3155: ** to the callback are either NULL pointers or zero-terminated strings
                   3156: ** that contain additional details about the action to be authorized.
                   3157: ** Applications must always be prepared to encounter a NULL pointer in any
                   3158: ** of the third through the sixth parameters of the authorization callback.
1.2       misho    3159: **
                   3160: ** ^If the action code is [SQLITE_READ]
                   3161: ** and the callback returns [SQLITE_IGNORE] then the
                   3162: ** [prepared statement] statement is constructed to substitute
                   3163: ** a NULL value in place of the table column that would have
                   3164: ** been read if [SQLITE_OK] had been returned.  The [SQLITE_IGNORE]
                   3165: ** return can be used to deny an untrusted user access to individual
                   3166: ** columns of a table.
1.5       misho    3167: ** ^When a table is referenced by a [SELECT] but no column values are
                   3168: ** extracted from that table (for example in a query like
                   3169: ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback
                   3170: ** is invoked once for that table with a column name that is an empty string.
1.2       misho    3171: ** ^If the action code is [SQLITE_DELETE] and the callback returns
                   3172: ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
                   3173: ** [truncate optimization] is disabled and all rows are deleted individually.
                   3174: **
                   3175: ** An authorizer is used when [sqlite3_prepare | preparing]
                   3176: ** SQL statements from an untrusted source, to ensure that the SQL statements
                   3177: ** do not try to access data they are not allowed to see, or that they do not
                   3178: ** try to execute malicious statements that damage the database.  For
                   3179: ** example, an application may allow a user to enter arbitrary
                   3180: ** SQL queries for evaluation by a database.  But the application does
                   3181: ** not want the user to be able to make arbitrary changes to the
                   3182: ** database.  An authorizer could then be put in place while the
                   3183: ** user-entered SQL is being [sqlite3_prepare | prepared] that
                   3184: ** disallows everything except [SELECT] statements.
                   3185: **
                   3186: ** Applications that need to process SQL from untrusted sources
                   3187: ** might also consider lowering resource limits using [sqlite3_limit()]
                   3188: ** and limiting database size using the [max_page_count] [PRAGMA]
                   3189: ** in addition to using an authorizer.
                   3190: **
                   3191: ** ^(Only a single authorizer can be in place on a database connection
                   3192: ** at a time.  Each call to sqlite3_set_authorizer overrides the
                   3193: ** previous call.)^  ^Disable the authorizer by installing a NULL callback.
                   3194: ** The authorizer is disabled by default.
                   3195: **
                   3196: ** The authorizer callback must not do anything that will modify
                   3197: ** the database connection that invoked the authorizer callback.
                   3198: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
                   3199: ** database connections for the meaning of "modify" in this paragraph.
                   3200: **
                   3201: ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
1.5       misho    3202: ** statement might be re-prepared during [sqlite3_step()] due to a
1.2       misho    3203: ** schema change.  Hence, the application should ensure that the
                   3204: ** correct authorizer callback remains in place during the [sqlite3_step()].
                   3205: **
                   3206: ** ^Note that the authorizer callback is invoked only during
                   3207: ** [sqlite3_prepare()] or its variants.  Authorization is not
                   3208: ** performed during statement evaluation in [sqlite3_step()], unless
                   3209: ** as stated in the previous paragraph, sqlite3_step() invokes
                   3210: ** sqlite3_prepare_v2() to reprepare a statement after a schema change.
                   3211: */
                   3212: SQLITE_API int sqlite3_set_authorizer(
                   3213:   sqlite3*,
                   3214:   int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
                   3215:   void *pUserData
                   3216: );
                   3217: 
                   3218: /*
                   3219: ** CAPI3REF: Authorizer Return Codes
                   3220: **
                   3221: ** The [sqlite3_set_authorizer | authorizer callback function] must
                   3222: ** return either [SQLITE_OK] or one of these two constants in order
                   3223: ** to signal SQLite whether or not the action is permitted.  See the
                   3224: ** [sqlite3_set_authorizer | authorizer documentation] for additional
                   3225: ** information.
                   3226: **
1.4       misho    3227: ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]
                   3228: ** returned from the [sqlite3_vtab_on_conflict()] interface.
1.2       misho    3229: */
                   3230: #define SQLITE_DENY   1   /* Abort the SQL statement with an error */
                   3231: #define SQLITE_IGNORE 2   /* Don't allow access, but don't generate an error */
                   3232: 
                   3233: /*
                   3234: ** CAPI3REF: Authorizer Action Codes
                   3235: **
                   3236: ** The [sqlite3_set_authorizer()] interface registers a callback function
                   3237: ** that is invoked to authorize certain SQL statement actions.  The
                   3238: ** second parameter to the callback is an integer code that specifies
                   3239: ** what action is being authorized.  These are the integer action codes that
                   3240: ** the authorizer callback may be passed.
                   3241: **
                   3242: ** These action code values signify what kind of operation is to be
                   3243: ** authorized.  The 3rd and 4th parameters to the authorization
                   3244: ** callback function will be parameters or NULL depending on which of these
                   3245: ** codes is used as the second parameter.  ^(The 5th parameter to the
                   3246: ** authorizer callback is the name of the database ("main", "temp",
                   3247: ** etc.) if applicable.)^  ^The 6th parameter to the authorizer callback
                   3248: ** is the name of the inner-most trigger or view that is responsible for
                   3249: ** the access attempt or NULL if this access attempt is directly from
                   3250: ** top-level SQL code.
                   3251: */
                   3252: /******************************************* 3rd ************ 4th ***********/
                   3253: #define SQLITE_CREATE_INDEX          1   /* Index Name      Table Name      */
                   3254: #define SQLITE_CREATE_TABLE          2   /* Table Name      NULL            */
                   3255: #define SQLITE_CREATE_TEMP_INDEX     3   /* Index Name      Table Name      */
                   3256: #define SQLITE_CREATE_TEMP_TABLE     4   /* Table Name      NULL            */
                   3257: #define SQLITE_CREATE_TEMP_TRIGGER   5   /* Trigger Name    Table Name      */
                   3258: #define SQLITE_CREATE_TEMP_VIEW      6   /* View Name       NULL            */
                   3259: #define SQLITE_CREATE_TRIGGER        7   /* Trigger Name    Table Name      */
                   3260: #define SQLITE_CREATE_VIEW           8   /* View Name       NULL            */
                   3261: #define SQLITE_DELETE                9   /* Table Name      NULL            */
                   3262: #define SQLITE_DROP_INDEX           10   /* Index Name      Table Name      */
                   3263: #define SQLITE_DROP_TABLE           11   /* Table Name      NULL            */
                   3264: #define SQLITE_DROP_TEMP_INDEX      12   /* Index Name      Table Name      */
                   3265: #define SQLITE_DROP_TEMP_TABLE      13   /* Table Name      NULL            */
                   3266: #define SQLITE_DROP_TEMP_TRIGGER    14   /* Trigger Name    Table Name      */
                   3267: #define SQLITE_DROP_TEMP_VIEW       15   /* View Name       NULL            */
                   3268: #define SQLITE_DROP_TRIGGER         16   /* Trigger Name    Table Name      */
                   3269: #define SQLITE_DROP_VIEW            17   /* View Name       NULL            */
                   3270: #define SQLITE_INSERT               18   /* Table Name      NULL            */
                   3271: #define SQLITE_PRAGMA               19   /* Pragma Name     1st arg or NULL */
                   3272: #define SQLITE_READ                 20   /* Table Name      Column Name     */
                   3273: #define SQLITE_SELECT               21   /* NULL            NULL            */
                   3274: #define SQLITE_TRANSACTION          22   /* Operation       NULL            */
                   3275: #define SQLITE_UPDATE               23   /* Table Name      Column Name     */
                   3276: #define SQLITE_ATTACH               24   /* Filename        NULL            */
                   3277: #define SQLITE_DETACH               25   /* Database Name   NULL            */
                   3278: #define SQLITE_ALTER_TABLE          26   /* Database Name   Table Name      */
                   3279: #define SQLITE_REINDEX              27   /* Index Name      NULL            */
                   3280: #define SQLITE_ANALYZE              28   /* Table Name      NULL            */
                   3281: #define SQLITE_CREATE_VTABLE        29   /* Table Name      Module Name     */
                   3282: #define SQLITE_DROP_VTABLE          30   /* Table Name      Module Name     */
                   3283: #define SQLITE_FUNCTION             31   /* NULL            Function Name   */
                   3284: #define SQLITE_SAVEPOINT            32   /* Operation       Savepoint Name  */
                   3285: #define SQLITE_COPY                  0   /* No longer used */
1.4       misho    3286: #define SQLITE_RECURSIVE            33   /* NULL            NULL            */
1.2       misho    3287: 
                   3288: /*
                   3289: ** CAPI3REF: Tracing And Profiling Functions
1.4       misho    3290: ** METHOD: sqlite3
                   3291: **
                   3292: ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface
                   3293: ** instead of the routines described here.
1.2       misho    3294: **
                   3295: ** These routines register callback functions that can be used for
                   3296: ** tracing and profiling the execution of SQL statements.
                   3297: **
                   3298: ** ^The callback function registered by sqlite3_trace() is invoked at
                   3299: ** various times when an SQL statement is being run by [sqlite3_step()].
                   3300: ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
                   3301: ** SQL statement text as the statement first begins executing.
                   3302: ** ^(Additional sqlite3_trace() callbacks might occur
                   3303: ** as each triggered subprogram is entered.  The callbacks for triggers
                   3304: ** contain a UTF-8 SQL comment that identifies the trigger.)^
                   3305: **
1.4       misho    3306: ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
                   3307: ** the length of [bound parameter] expansion in the output of sqlite3_trace().
                   3308: **
1.2       misho    3309: ** ^The callback function registered by sqlite3_profile() is invoked
                   3310: ** as each SQL statement finishes.  ^The profile callback contains
                   3311: ** the original statement text and an estimate of wall-clock time
                   3312: ** of how long that statement took to run.  ^The profile callback
                   3313: ** time is in units of nanoseconds, however the current implementation
                   3314: ** is only capable of millisecond resolution so the six least significant
                   3315: ** digits in the time are meaningless.  Future versions of SQLite
1.5       misho    3316: ** might provide greater resolution on the profiler callback.  Invoking
                   3317: ** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the
                   3318: ** profile callback.
1.2       misho    3319: */
1.4       misho    3320: SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*,
                   3321:    void(*xTrace)(void*,const char*), void*);
                   3322: SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*,
1.2       misho    3323:    void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
                   3324: 
                   3325: /*
1.4       misho    3326: ** CAPI3REF: SQL Trace Event Codes
                   3327: ** KEYWORDS: SQLITE_TRACE
                   3328: **
                   3329: ** These constants identify classes of events that can be monitored
1.5       misho    3330: ** using the [sqlite3_trace_v2()] tracing logic.  The M argument
                   3331: ** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
1.4       misho    3332: ** the following constants.  ^The first argument to the trace callback
                   3333: ** is one of the following constants.
                   3334: **
                   3335: ** New tracing constants may be added in future releases.
                   3336: **
                   3337: ** ^A trace callback has four arguments: xCallback(T,C,P,X).
                   3338: ** ^The T argument is one of the integer type codes above.
                   3339: ** ^The C argument is a copy of the context pointer passed in as the
                   3340: ** fourth argument to [sqlite3_trace_v2()].
                   3341: ** The P and X arguments are pointers whose meanings depend on T.
                   3342: **
                   3343: ** <dl>
                   3344: ** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>
                   3345: ** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement
                   3346: ** first begins running and possibly at other times during the
                   3347: ** execution of the prepared statement, such as at the start of each
                   3348: ** trigger subprogram. ^The P argument is a pointer to the
                   3349: ** [prepared statement]. ^The X argument is a pointer to a string which
1.5       misho    3350: ** is the unexpanded SQL text of the prepared statement or an SQL comment
1.4       misho    3351: ** that indicates the invocation of a trigger.  ^The callback can compute
                   3352: ** the same text that would have been returned by the legacy [sqlite3_trace()]
                   3353: ** interface by using the X argument when X begins with "--" and invoking
                   3354: ** [sqlite3_expanded_sql(P)] otherwise.
                   3355: **
                   3356: ** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>
                   3357: ** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same
                   3358: ** information as is provided by the [sqlite3_profile()] callback.
                   3359: ** ^The P argument is a pointer to the [prepared statement] and the
1.6.2.1 ! misho    3360: ** X argument points to a 64-bit integer which is approximately
        !          3361: ** the number of nanoseconds that the prepared statement took to run.
1.4       misho    3362: ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.
                   3363: **
                   3364: ** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>
                   3365: ** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared
1.5       misho    3366: ** statement generates a single row of result.
1.4       misho    3367: ** ^The P argument is a pointer to the [prepared statement] and the
                   3368: ** X argument is unused.
                   3369: **
                   3370: ** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>
                   3371: ** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database
                   3372: ** connection closes.
                   3373: ** ^The P argument is a pointer to the [database connection] object
                   3374: ** and the X argument is unused.
                   3375: ** </dl>
                   3376: */
                   3377: #define SQLITE_TRACE_STMT       0x01
                   3378: #define SQLITE_TRACE_PROFILE    0x02
                   3379: #define SQLITE_TRACE_ROW        0x04
                   3380: #define SQLITE_TRACE_CLOSE      0x08
                   3381: 
                   3382: /*
                   3383: ** CAPI3REF: SQL Trace Hook
                   3384: ** METHOD: sqlite3
                   3385: **
                   3386: ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback
                   3387: ** function X against [database connection] D, using property mask M
                   3388: ** and context pointer P.  ^If the X callback is
                   3389: ** NULL or if the M mask is zero, then tracing is disabled.  The
                   3390: ** M argument should be the bitwise OR-ed combination of
                   3391: ** zero or more [SQLITE_TRACE] constants.
                   3392: **
1.6.2.1 ! misho    3393: ** ^Each call to either sqlite3_trace(D,X,P) or sqlite3_trace_v2(D,M,X,P)
        !          3394: ** overrides (cancels) all prior calls to sqlite3_trace(D,X,P) or
        !          3395: ** sqlite3_trace_v2(D,M,X,P) for the [database connection] D.  Each
        !          3396: ** database connection may have at most one trace callback.
1.4       misho    3397: **
1.5       misho    3398: ** ^The X callback is invoked whenever any of the events identified by
1.4       misho    3399: ** mask M occur.  ^The integer return value from the callback is currently
                   3400: ** ignored, though this may change in future releases.  Callback
                   3401: ** implementations should return zero to ensure future compatibility.
                   3402: **
                   3403: ** ^A trace callback is invoked with four arguments: callback(T,C,P,X).
                   3404: ** ^The T argument is one of the [SQLITE_TRACE]
                   3405: ** constants to indicate why the callback was invoked.
                   3406: ** ^The C argument is a copy of the context pointer.
                   3407: ** The P and X arguments are pointers whose meanings depend on T.
                   3408: **
                   3409: ** The sqlite3_trace_v2() interface is intended to replace the legacy
                   3410: ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which
                   3411: ** are deprecated.
                   3412: */
                   3413: SQLITE_API int sqlite3_trace_v2(
                   3414:   sqlite3*,
                   3415:   unsigned uMask,
                   3416:   int(*xCallback)(unsigned,void*,void*,void*),
                   3417:   void *pCtx
                   3418: );
                   3419: 
                   3420: /*
1.2       misho    3421: ** CAPI3REF: Query Progress Callbacks
1.4       misho    3422: ** METHOD: sqlite3
1.2       misho    3423: **
                   3424: ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
                   3425: ** function X to be invoked periodically during long running calls to
1.6.2.1 ! misho    3426: ** [sqlite3_step()] and [sqlite3_prepare()] and similar for
1.2       misho    3427: ** database connection D.  An example use for this
                   3428: ** interface is to keep a GUI updated during a large query.
                   3429: **
1.5       misho    3430: ** ^The parameter P is passed through as the only parameter to the
                   3431: ** callback function X.  ^The parameter N is the approximate number of
1.2       misho    3432: ** [virtual machine instructions] that are evaluated between successive
1.4       misho    3433: ** invocations of the callback X.  ^If N is less than one then the progress
                   3434: ** handler is disabled.
1.2       misho    3435: **
                   3436: ** ^Only a single progress handler may be defined at one time per
                   3437: ** [database connection]; setting a new progress handler cancels the
                   3438: ** old one.  ^Setting parameter X to NULL disables the progress handler.
                   3439: ** ^The progress handler is also disabled by setting N to a value less
                   3440: ** than 1.
                   3441: **
                   3442: ** ^If the progress callback returns non-zero, the operation is
                   3443: ** interrupted.  This feature can be used to implement a
                   3444: ** "Cancel" button on a GUI progress dialog box.
                   3445: **
                   3446: ** The progress handler callback must not do anything that will modify
                   3447: ** the database connection that invoked the progress handler.
                   3448: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
                   3449: ** database connections for the meaning of "modify" in this paragraph.
                   3450: **
1.6.2.1 ! misho    3451: ** The progress handler callback would originally only be invoked from the
        !          3452: ** bytecode engine.  It still might be invoked during [sqlite3_prepare()]
        !          3453: ** and similar because those routines might force a reparse of the schema
        !          3454: ** which involves running the bytecode engine.  However, beginning with
        !          3455: ** SQLite version 3.41.0, the progress handler callback might also be
        !          3456: ** invoked directly from [sqlite3_prepare()] while analyzing and generating
        !          3457: ** code for complex queries.
1.2       misho    3458: */
                   3459: SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
                   3460: 
                   3461: /*
                   3462: ** CAPI3REF: Opening A New Database Connection
1.4       misho    3463: ** CONSTRUCTOR: sqlite3
1.2       misho    3464: **
1.5       misho    3465: ** ^These routines open an SQLite database file as specified by the
1.2       misho    3466: ** filename argument. ^The filename argument is interpreted as UTF-8 for
                   3467: ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
                   3468: ** order for sqlite3_open16(). ^(A [database connection] handle is usually
                   3469: ** returned in *ppDb, even if an error occurs.  The only exception is that
                   3470: ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
                   3471: ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
                   3472: ** object.)^ ^(If the database is opened (and/or created) successfully, then
                   3473: ** [SQLITE_OK] is returned.  Otherwise an [error code] is returned.)^ ^The
                   3474: ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
                   3475: ** an English language description of the error following a failure of any
                   3476: ** of the sqlite3_open() routines.
                   3477: **
1.4       misho    3478: ** ^The default encoding will be UTF-8 for databases created using
                   3479: ** sqlite3_open() or sqlite3_open_v2().  ^The default encoding for databases
                   3480: ** created using sqlite3_open16() will be UTF-16 in the native byte order.
1.2       misho    3481: **
                   3482: ** Whether or not an error occurs when it is opened, resources
                   3483: ** associated with the [database connection] handle should be released by
                   3484: ** passing it to [sqlite3_close()] when it is no longer required.
                   3485: **
                   3486: ** The sqlite3_open_v2() interface works like sqlite3_open()
                   3487: ** except that it accepts two additional parameters for additional control
                   3488: ** over the new database connection.  ^(The flags parameter to
1.5       misho    3489: ** sqlite3_open_v2() must include, at a minimum, one of the following
                   3490: ** three flag combinations:)^
1.2       misho    3491: **
                   3492: ** <dl>
                   3493: ** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
1.6.2.1 ! misho    3494: ** <dd>The database is opened in read-only mode.  If the database does
        !          3495: ** not already exist, an error is returned.</dd>)^
1.2       misho    3496: **
                   3497: ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
1.6.2.1 ! misho    3498: ** <dd>The database is opened for reading and writing if possible, or
        !          3499: ** reading only if the file is write protected by the operating
        !          3500: ** system.  In either case the database must already exist, otherwise
        !          3501: ** an error is returned.  For historical reasons, if opening in
        !          3502: ** read-write mode fails due to OS-level permissions, an attempt is
        !          3503: ** made to open it in read-only mode. [sqlite3_db_readonly()] can be
        !          3504: ** used to determine whether the database is actually
        !          3505: ** read-write.</dd>)^
1.2       misho    3506: **
                   3507: ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
                   3508: ** <dd>The database is opened for reading and writing, and is created if
                   3509: ** it does not already exist. This is the behavior that is always used for
                   3510: ** sqlite3_open() and sqlite3_open16().</dd>)^
                   3511: ** </dl>
                   3512: **
1.5       misho    3513: ** In addition to the required flags, the following optional flags are
                   3514: ** also supported:
                   3515: **
                   3516: ** <dl>
                   3517: ** ^(<dt>[SQLITE_OPEN_URI]</dt>
                   3518: ** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^
                   3519: **
                   3520: ** ^(<dt>[SQLITE_OPEN_MEMORY]</dt>
                   3521: ** <dd>The database will be opened as an in-memory database.  The database
                   3522: ** is named by the "filename" argument for the purposes of cache-sharing,
                   3523: ** if shared cache mode is enabled, but the "filename" is otherwise ignored.
                   3524: ** </dd>)^
                   3525: **
                   3526: ** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt>
                   3527: ** <dd>The new database connection will use the "multi-thread"
                   3528: ** [threading mode].)^  This means that separate threads are allowed
                   3529: ** to use SQLite at the same time, as long as each thread is using
                   3530: ** a different [database connection].
                   3531: **
                   3532: ** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt>
                   3533: ** <dd>The new database connection will use the "serialized"
                   3534: ** [threading mode].)^  This means the multiple threads can safely
                   3535: ** attempt to use the same database connection at the same time.
                   3536: ** (Mutexes will block any actual concurrency, but in this mode
                   3537: ** there is no harm in trying.)
                   3538: **
                   3539: ** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt>
                   3540: ** <dd>The database is opened [shared cache] enabled, overriding
                   3541: ** the default shared cache setting provided by
                   3542: ** [sqlite3_enable_shared_cache()].)^
1.6.2.1 ! misho    3543: ** The [use of shared cache mode is discouraged] and hence shared cache
        !          3544: ** capabilities may be omitted from many builds of SQLite.  In such cases,
        !          3545: ** this option is a no-op.
1.5       misho    3546: **
                   3547: ** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt>
                   3548: ** <dd>The database is opened [shared cache] disabled, overriding
                   3549: ** the default shared cache setting provided by
                   3550: ** [sqlite3_enable_shared_cache()].)^
                   3551: **
1.6.2.1 ! misho    3552: ** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt>
        !          3553: ** <dd>The database connection comes up in "extended result code mode".
        !          3554: ** In other words, the database behaves has if
        !          3555: ** [sqlite3_extended_result_codes(db,1)] where called on the database
        !          3556: ** connection as soon as the connection is created. In addition to setting
        !          3557: ** the extended result code mode, this flag also causes [sqlite3_open_v2()]
        !          3558: ** to return an extended result code.</dd>
        !          3559: **
1.5       misho    3560: ** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt>
1.6.2.1 ! misho    3561: ** <dd>The database filename is not allowed to contain a symbolic link</dd>
1.5       misho    3562: ** </dl>)^
                   3563: **
1.2       misho    3564: ** If the 3rd parameter to sqlite3_open_v2() is not one of the
1.5       misho    3565: ** required combinations shown above optionally combined with other
1.2       misho    3566: ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
1.6.2.1 ! misho    3567: ** then the behavior is undefined.  Historic versions of SQLite
        !          3568: ** have silently ignored surplus bits in the flags parameter to
        !          3569: ** sqlite3_open_v2(), however that behavior might not be carried through
        !          3570: ** into future versions of SQLite and so applications should not rely
        !          3571: ** upon it.  Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op
        !          3572: ** for sqlite3_open_v2().  The SQLITE_OPEN_EXCLUSIVE does *not* cause
        !          3573: ** the open to fail if the database already exists.  The SQLITE_OPEN_EXCLUSIVE
        !          3574: ** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not
        !          3575: ** by sqlite3_open_v2().
1.2       misho    3576: **
                   3577: ** ^The fourth parameter to sqlite3_open_v2() is the name of the
                   3578: ** [sqlite3_vfs] object that defines the operating system interface that
                   3579: ** the new database connection should use.  ^If the fourth parameter is
                   3580: ** a NULL pointer then the default [sqlite3_vfs] object is used.
                   3581: **
                   3582: ** ^If the filename is ":memory:", then a private, temporary in-memory database
                   3583: ** is created for the connection.  ^This in-memory database will vanish when
                   3584: ** the database connection is closed.  Future versions of SQLite might
                   3585: ** make use of additional special filenames that begin with the ":" character.
                   3586: ** It is recommended that when a database filename actually does begin with
                   3587: ** a ":" character you should prefix the filename with a pathname such as
                   3588: ** "./" to avoid ambiguity.
                   3589: **
                   3590: ** ^If the filename is an empty string, then a private, temporary
                   3591: ** on-disk database will be created.  ^This private database will be
                   3592: ** automatically deleted as soon as the database connection is closed.
                   3593: **
                   3594: ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
                   3595: **
                   3596: ** ^If [URI filename] interpretation is enabled, and the filename argument
                   3597: ** begins with "file:", then the filename is interpreted as a URI. ^URI
                   3598: ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
1.5       misho    3599: ** set in the third argument to sqlite3_open_v2(), or if it has
1.2       misho    3600: ** been enabled globally using the [SQLITE_CONFIG_URI] option with the
                   3601: ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
1.5       misho    3602: ** URI filename interpretation is turned off
1.2       misho    3603: ** by default, but future releases of SQLite might enable URI filename
                   3604: ** interpretation by default.  See "[URI filenames]" for additional
                   3605: ** information.
                   3606: **
                   3607: ** URI filenames are parsed according to RFC 3986. ^If the URI contains an
1.5       misho    3608: ** authority, then it must be either an empty string or the string
                   3609: ** "localhost". ^If the authority is not an empty string or "localhost", an
                   3610: ** error is returned to the caller. ^The fragment component of a URI, if
1.2       misho    3611: ** present, is ignored.
                   3612: **
                   3613: ** ^SQLite uses the path component of the URI as the name of the disk file
1.5       misho    3614: ** which contains the database. ^If the path begins with a '/' character,
                   3615: ** then it is interpreted as an absolute path. ^If the path does not begin
1.2       misho    3616: ** with a '/' (meaning that the authority section is omitted from the URI)
1.5       misho    3617: ** then the path is interpreted as a relative path.
                   3618: ** ^(On windows, the first component of an absolute path
1.4       misho    3619: ** is a drive specification (e.g. "C:").)^
1.2       misho    3620: **
                   3621: ** [[core URI query parameters]]
                   3622: ** The query component of a URI may contain parameters that are interpreted
                   3623: ** either by SQLite itself, or by a [VFS | custom VFS implementation].
1.4       misho    3624: ** SQLite and its built-in [VFSes] interpret the
                   3625: ** following query parameters:
1.2       misho    3626: **
                   3627: ** <ul>
                   3628: **   <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
                   3629: **     a VFS object that provides the operating system interface that should
                   3630: **     be used to access the database file on disk. ^If this option is set to
                   3631: **     an empty string the default VFS object is used. ^Specifying an unknown
                   3632: **     VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
                   3633: **     present, then the VFS specified by the option takes precedence over
                   3634: **     the value passed as the fourth parameter to sqlite3_open_v2().
                   3635: **
1.3       misho    3636: **   <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",
                   3637: **     "rwc", or "memory". Attempting to set it to any other value is
1.5       misho    3638: **     an error)^.
                   3639: **     ^If "ro" is specified, then the database is opened for read-only
                   3640: **     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
                   3641: **     third argument to sqlite3_open_v2(). ^If the mode option is set to
                   3642: **     "rw", then the database is opened for read-write (but not create)
                   3643: **     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
                   3644: **     been set. ^Value "rwc" is equivalent to setting both
1.3       misho    3645: **     SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE.  ^If the mode option is
                   3646: **     set to "memory" then a pure [in-memory database] that never reads
                   3647: **     or writes from disk is used. ^It is an error to specify a value for
                   3648: **     the mode parameter that is less restrictive than that specified by
                   3649: **     the flags passed in the third parameter to sqlite3_open_v2().
1.2       misho    3650: **
                   3651: **   <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
                   3652: **     "private". ^Setting it to "shared" is equivalent to setting the
                   3653: **     SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
1.5       misho    3654: **     sqlite3_open_v2(). ^Setting the cache parameter to "private" is
1.2       misho    3655: **     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
                   3656: **     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
1.4       misho    3657: **     a URI filename, its value overrides any behavior requested by setting
1.2       misho    3658: **     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
1.4       misho    3659: **
                   3660: **  <li> <b>psow</b>: ^The psow parameter indicates whether or not the
                   3661: **     [powersafe overwrite] property does or does not apply to the
                   3662: **     storage media on which the database file resides.
                   3663: **
                   3664: **  <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter
                   3665: **     which if set disables file locking in rollback journal modes.  This
                   3666: **     is useful for accessing a database on a filesystem that does not
                   3667: **     support locking.  Caution:  Database corruption might result if two
                   3668: **     or more processes write to the same database and any one of those
                   3669: **     processes uses nolock=1.
                   3670: **
                   3671: **  <li> <b>immutable</b>: ^The immutable parameter is a boolean query
                   3672: **     parameter that indicates that the database file is stored on
                   3673: **     read-only media.  ^When immutable is set, SQLite assumes that the
                   3674: **     database file cannot be changed, even by a process with higher
                   3675: **     privilege, and so the database is opened read-only and all locking
                   3676: **     and change detection is disabled.  Caution: Setting the immutable
                   3677: **     property on a database file that does in fact change can result
                   3678: **     in incorrect query results and/or [SQLITE_CORRUPT] errors.
                   3679: **     See also: [SQLITE_IOCAP_IMMUTABLE].
1.5       misho    3680: **
1.2       misho    3681: ** </ul>
                   3682: **
                   3683: ** ^Specifying an unknown parameter in the query component of a URI is not an
                   3684: ** error.  Future versions of SQLite might understand additional query
                   3685: ** parameters.  See "[query parameters with special meaning to SQLite]" for
                   3686: ** additional information.
                   3687: **
                   3688: ** [[URI filename examples]] <h3>URI filename examples</h3>
                   3689: **
                   3690: ** <table border="1" align=center cellpadding=5>
                   3691: ** <tr><th> URI filenames <th> Results
1.5       misho    3692: ** <tr><td> file:data.db <td>
1.2       misho    3693: **          Open the file "data.db" in the current directory.
                   3694: ** <tr><td> file:/home/fred/data.db<br>
1.5       misho    3695: **          file:///home/fred/data.db <br>
                   3696: **          file://localhost/home/fred/data.db <br> <td>
1.2       misho    3697: **          Open the database file "/home/fred/data.db".
1.5       misho    3698: ** <tr><td> file://darkstar/home/fred/data.db <td>
1.2       misho    3699: **          An error. "darkstar" is not a recognized authority.
1.5       misho    3700: ** <tr><td style="white-space:nowrap">
1.2       misho    3701: **          file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
                   3702: **     <td> Windows only: Open the file "data.db" on fred's desktop on drive
1.5       misho    3703: **          C:. Note that the %20 escaping in this example is not strictly
1.2       misho    3704: **          necessary - space characters can be used literally
                   3705: **          in URI filenames.
1.5       misho    3706: ** <tr><td> file:data.db?mode=ro&cache=private <td>
1.2       misho    3707: **          Open file "data.db" in the current directory for read-only access.
                   3708: **          Regardless of whether or not shared-cache mode is enabled by
                   3709: **          default, use a private cache.
1.4       misho    3710: ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>
                   3711: **          Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"
                   3712: **          that uses dot-files in place of posix advisory locking.
1.5       misho    3713: ** <tr><td> file:data.db?mode=readonly <td>
1.2       misho    3714: **          An error. "readonly" is not a valid option for the "mode" parameter.
1.6       misho    3715: **          Use "ro" instead:  "file:data.db?mode=ro".
1.2       misho    3716: ** </table>
                   3717: **
                   3718: ** ^URI hexadecimal escape sequences (%HH) are supported within the path and
                   3719: ** query components of a URI. A hexadecimal escape sequence consists of a
1.5       misho    3720: ** percent sign - "%" - followed by exactly two hexadecimal digits
1.2       misho    3721: ** specifying an octet value. ^Before the path or query components of a
1.5       misho    3722: ** URI filename are interpreted, they are encoded using UTF-8 and all
1.2       misho    3723: ** hexadecimal escape sequences replaced by a single byte containing the
                   3724: ** corresponding octet. If this process generates an invalid UTF-8 encoding,
                   3725: ** the results are undefined.
                   3726: **
                   3727: ** <b>Note to Windows users:</b>  The encoding used for the filename argument
                   3728: ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
                   3729: ** codepage is currently defined.  Filenames containing international
                   3730: ** characters must be converted to UTF-8 prior to passing them into
                   3731: ** sqlite3_open() or sqlite3_open_v2().
1.3       misho    3732: **
                   3733: ** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
                   3734: ** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
                   3735: ** features that require the use of temporary files may fail.
                   3736: **
                   3737: ** See also: [sqlite3_temp_directory]
1.2       misho    3738: */
                   3739: SQLITE_API int sqlite3_open(
                   3740:   const char *filename,   /* Database filename (UTF-8) */
                   3741:   sqlite3 **ppDb          /* OUT: SQLite db handle */
                   3742: );
                   3743: SQLITE_API int sqlite3_open16(
                   3744:   const void *filename,   /* Database filename (UTF-16) */
                   3745:   sqlite3 **ppDb          /* OUT: SQLite db handle */
                   3746: );
                   3747: SQLITE_API int sqlite3_open_v2(
                   3748:   const char *filename,   /* Database filename (UTF-8) */
                   3749:   sqlite3 **ppDb,         /* OUT: SQLite db handle */
                   3750:   int flags,              /* Flags */
                   3751:   const char *zVfs        /* Name of VFS module to use */
                   3752: );
                   3753: 
                   3754: /*
                   3755: ** CAPI3REF: Obtain Values For URI Parameters
                   3756: **
1.5       misho    3757: ** These are utility routines, useful to [VFS|custom VFS implementations],
                   3758: ** that check if a database file was a URI that contained a specific query
1.2       misho    3759: ** parameter, and if so obtains the value of that query parameter.
                   3760: **
1.5       misho    3761: ** The first parameter to these interfaces (hereafter referred to
                   3762: ** as F) must be one of:
                   3763: ** <ul>
                   3764: ** <li> A database filename pointer created by the SQLite core and
1.6.2.1 ! misho    3765: ** passed into the xOpen() method of a VFS implementation, or
1.5       misho    3766: ** <li> A filename obtained from [sqlite3_db_filename()], or
                   3767: ** <li> A new filename constructed using [sqlite3_create_filename()].
                   3768: ** </ul>
                   3769: ** If the F parameter is not one of the above, then the behavior is
                   3770: ** undefined and probably undesirable.  Older versions of SQLite were
                   3771: ** more tolerant of invalid F parameters than newer versions.
                   3772: **
                   3773: ** If F is a suitable filename (as described in the previous paragraph)
                   3774: ** and if P is the name of the query parameter, then
1.2       misho    3775: ** sqlite3_uri_parameter(F,P) returns the value of the P
1.5       misho    3776: ** parameter if it exists or a NULL pointer if P does not appear as a
                   3777: ** query parameter on F.  If P is a query parameter of F and it
1.2       misho    3778: ** has no explicit value, then sqlite3_uri_parameter(F,P) returns
                   3779: ** a pointer to an empty string.
                   3780: **
                   3781: ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
                   3782: ** parameter and returns true (1) or false (0) according to the value
1.3       misho    3783: ** of P.  The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the
                   3784: ** value of query parameter P is one of "yes", "true", or "on" in any
1.5       misho    3785: ** case or if the value begins with a non-zero number.  The
1.3       misho    3786: ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of
                   3787: ** query parameter P is one of "no", "false", or "off" in any case or
                   3788: ** if the value begins with a numeric zero.  If P is not a query
1.5       misho    3789: ** parameter on F or if the value of P does not match any of the
1.3       misho    3790: ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).
1.2       misho    3791: **
                   3792: ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
                   3793: ** 64-bit signed integer and returns that integer, or D if P does not
                   3794: ** exist.  If the value of P is something other than an integer, then
                   3795: ** zero is returned.
1.5       misho    3796: **
                   3797: ** The sqlite3_uri_key(F,N) returns a pointer to the name (not
                   3798: ** the value) of the N-th query parameter for filename F, or a NULL
                   3799: ** pointer if N is less than zero or greater than the number of query
                   3800: ** parameters minus 1.  The N value is zero-based so N should be 0 to obtain
                   3801: ** the name of the first query parameter, 1 for the second parameter, and
                   3802: ** so forth.
                   3803: **
1.2       misho    3804: ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
                   3805: ** sqlite3_uri_boolean(F,P,B) returns B.  If F is not a NULL pointer and
1.5       misho    3806: ** is not a database file pathname pointer that the SQLite core passed
                   3807: ** into the xOpen VFS method, then the behavior of this routine is undefined
                   3808: ** and probably undesirable.
                   3809: **
                   3810: ** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F
                   3811: ** parameter can also be the name of a rollback journal file or WAL file
                   3812: ** in addition to the main database file.  Prior to version 3.31.0, these
                   3813: ** routines would only work if F was the name of the main database file.
                   3814: ** When the F parameter is the name of the rollback journal or WAL file,
                   3815: ** it has access to all the same query parameters as were found on the
                   3816: ** main database file.
                   3817: **
                   3818: ** See the [URI filename] documentation for additional information.
1.2       misho    3819: */
1.6.2.1 ! misho    3820: SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam);
        !          3821: SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault);
        !          3822: SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64);
        !          3823: SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N);
1.2       misho    3824: 
1.5       misho    3825: /*
                   3826: ** CAPI3REF:  Translate filenames
                   3827: **
                   3828: ** These routines are available to [VFS|custom VFS implementations] for
                   3829: ** translating filenames between the main database file, the journal file,
                   3830: ** and the WAL file.
                   3831: **
                   3832: ** If F is the name of an sqlite database file, journal file, or WAL file
                   3833: ** passed by the SQLite core into the VFS, then sqlite3_filename_database(F)
                   3834: ** returns the name of the corresponding database file.
                   3835: **
                   3836: ** If F is the name of an sqlite database file, journal file, or WAL file
                   3837: ** passed by the SQLite core into the VFS, or if F is a database filename
                   3838: ** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F)
                   3839: ** returns the name of the corresponding rollback journal file.
                   3840: **
                   3841: ** If F is the name of an sqlite database file, journal file, or WAL file
                   3842: ** that was passed by the SQLite core into the VFS, or if F is a database
                   3843: ** filename obtained from [sqlite3_db_filename()], then
                   3844: ** sqlite3_filename_wal(F) returns the name of the corresponding
                   3845: ** WAL file.
                   3846: **
                   3847: ** In all of the above, if F is not the name of a database, journal or WAL
                   3848: ** filename passed into the VFS from the SQLite core and F is not the
                   3849: ** return value from [sqlite3_db_filename()], then the result is
                   3850: ** undefined and is likely a memory access violation.
                   3851: */
1.6.2.1 ! misho    3852: SQLITE_API const char *sqlite3_filename_database(sqlite3_filename);
        !          3853: SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename);
        !          3854: SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename);
1.5       misho    3855: 
                   3856: /*
                   3857: ** CAPI3REF:  Database File Corresponding To A Journal
                   3858: **
                   3859: ** ^If X is the name of a rollback or WAL-mode journal file that is
                   3860: ** passed into the xOpen method of [sqlite3_vfs], then
                   3861: ** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]
                   3862: ** object that represents the main database file.
                   3863: **
                   3864: ** This routine is intended for use in custom [VFS] implementations
                   3865: ** only.  It is not a general-purpose interface.
                   3866: ** The argument sqlite3_file_object(X) must be a filename pointer that
                   3867: ** has been passed into [sqlite3_vfs].xOpen method where the
                   3868: ** flags parameter to xOpen contains one of the bits
                   3869: ** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL].  Any other use
                   3870: ** of this routine results in undefined and probably undesirable
                   3871: ** behavior.
                   3872: */
                   3873: SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*);
                   3874: 
                   3875: /*
                   3876: ** CAPI3REF: Create and Destroy VFS Filenames
                   3877: **
1.6.2.1 ! misho    3878: ** These interfaces are provided for use by [VFS shim] implementations and
1.5       misho    3879: ** are not useful outside of that context.
                   3880: **
                   3881: ** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of
                   3882: ** database filename D with corresponding journal file J and WAL file W and
                   3883: ** with N URI parameters key/values pairs in the array P.  The result from
                   3884: ** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that
                   3885: ** is safe to pass to routines like:
                   3886: ** <ul>
                   3887: ** <li> [sqlite3_uri_parameter()],
                   3888: ** <li> [sqlite3_uri_boolean()],
                   3889: ** <li> [sqlite3_uri_int64()],
                   3890: ** <li> [sqlite3_uri_key()],
                   3891: ** <li> [sqlite3_filename_database()],
                   3892: ** <li> [sqlite3_filename_journal()], or
                   3893: ** <li> [sqlite3_filename_wal()].
                   3894: ** </ul>
                   3895: ** If a memory allocation error occurs, sqlite3_create_filename() might
                   3896: ** return a NULL pointer.  The memory obtained from sqlite3_create_filename(X)
                   3897: ** must be released by a corresponding call to sqlite3_free_filename(Y).
                   3898: **
                   3899: ** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array
                   3900: ** of 2*N pointers to strings.  Each pair of pointers in this array corresponds
                   3901: ** to a key and value for a query parameter.  The P parameter may be a NULL
                   3902: ** pointer if N is zero.  None of the 2*N pointers in the P array may be
                   3903: ** NULL pointers and key pointers should not be empty strings.
                   3904: ** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may
                   3905: ** be NULL pointers, though they can be empty strings.
                   3906: **
                   3907: ** The sqlite3_free_filename(Y) routine releases a memory allocation
                   3908: ** previously obtained from sqlite3_create_filename().  Invoking
                   3909: ** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op.
                   3910: **
                   3911: ** If the Y parameter to sqlite3_free_filename(Y) is anything other
                   3912: ** than a NULL pointer or a pointer previously acquired from
                   3913: ** sqlite3_create_filename(), then bad things such as heap
1.6       misho    3914: ** corruption or segfaults may occur. The value Y should not be
1.5       misho    3915: ** used again after sqlite3_free_filename(Y) has been called.  This means
                   3916: ** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
                   3917: ** then the corresponding [sqlite3_module.xClose() method should also be
                   3918: ** invoked prior to calling sqlite3_free_filename(Y).
                   3919: */
1.6.2.1 ! misho    3920: SQLITE_API sqlite3_filename sqlite3_create_filename(
1.5       misho    3921:   const char *zDatabase,
                   3922:   const char *zJournal,
                   3923:   const char *zWal,
                   3924:   int nParam,
                   3925:   const char **azParam
                   3926: );
1.6.2.1 ! misho    3927: SQLITE_API void sqlite3_free_filename(sqlite3_filename);
1.2       misho    3928: 
                   3929: /*
                   3930: ** CAPI3REF: Error Codes And Messages
1.4       misho    3931: ** METHOD: sqlite3
1.2       misho    3932: **
1.5       misho    3933: ** ^If the most recent sqlite3_* API call associated with
1.4       misho    3934: ** [database connection] D failed, then the sqlite3_errcode(D) interface
                   3935: ** returns the numeric [result code] or [extended result code] for that
                   3936: ** API call.
                   3937: ** ^The sqlite3_extended_errcode()
1.5       misho    3938: ** interface is the same except that it always returns the
1.2       misho    3939: ** [extended result code] even when extended result codes are
                   3940: ** disabled.
                   3941: **
1.5       misho    3942: ** The values returned by sqlite3_errcode() and/or
                   3943: ** sqlite3_extended_errcode() might change with each API call.
                   3944: ** Except, there are some interfaces that are guaranteed to never
                   3945: ** change the value of the error code.  The error-code preserving
1.6.2.1 ! misho    3946: ** interfaces include the following:
1.5       misho    3947: **
                   3948: ** <ul>
                   3949: ** <li> sqlite3_errcode()
                   3950: ** <li> sqlite3_extended_errcode()
                   3951: ** <li> sqlite3_errmsg()
                   3952: ** <li> sqlite3_errmsg16()
1.6.2.1 ! misho    3953: ** <li> sqlite3_error_offset()
1.5       misho    3954: ** </ul>
                   3955: **
1.2       misho    3956: ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
                   3957: ** text that describes the error, as either UTF-8 or UTF-16 respectively.
                   3958: ** ^(Memory to hold the error message string is managed internally.
                   3959: ** The application does not need to worry about freeing the result.
                   3960: ** However, the error string might be overwritten or deallocated by
                   3961: ** subsequent calls to other SQLite interface functions.)^
                   3962: **
1.3       misho    3963: ** ^The sqlite3_errstr() interface returns the English-language text
                   3964: ** that describes the [result code], as UTF-8.
                   3965: ** ^(Memory to hold the error message string is managed internally
                   3966: ** and must not be freed by the application)^.
                   3967: **
1.6.2.1 ! misho    3968: ** ^If the most recent error references a specific token in the input
        !          3969: ** SQL, the sqlite3_error_offset() interface returns the byte offset
        !          3970: ** of the start of that token.  ^The byte offset returned by
        !          3971: ** sqlite3_error_offset() assumes that the input SQL is UTF8.
        !          3972: ** ^If the most recent error does not reference a specific token in the input
        !          3973: ** SQL, then the sqlite3_error_offset() function returns -1.
        !          3974: **
1.2       misho    3975: ** When the serialized [threading mode] is in use, it might be the
                   3976: ** case that a second error occurs on a separate thread in between
                   3977: ** the time of the first error and the call to these interfaces.
                   3978: ** When that happens, the second error will be reported since these
                   3979: ** interfaces always report the most recent result.  To avoid
                   3980: ** this, each thread can obtain exclusive use of the [database connection] D
                   3981: ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
                   3982: ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
                   3983: ** all calls to the interfaces listed here are completed.
                   3984: **
                   3985: ** If an interface fails with SQLITE_MISUSE, that means the interface
                   3986: ** was invoked incorrectly by the application.  In that case, the
                   3987: ** error code and message may or may not be set.
                   3988: */
                   3989: SQLITE_API int sqlite3_errcode(sqlite3 *db);
                   3990: SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
                   3991: SQLITE_API const char *sqlite3_errmsg(sqlite3*);
                   3992: SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
1.3       misho    3993: SQLITE_API const char *sqlite3_errstr(int);
1.6.2.1 ! misho    3994: SQLITE_API int sqlite3_error_offset(sqlite3 *db);
1.2       misho    3995: 
                   3996: /*
1.4       misho    3997: ** CAPI3REF: Prepared Statement Object
1.2       misho    3998: ** KEYWORDS: {prepared statement} {prepared statements}
                   3999: **
1.4       misho    4000: ** An instance of this object represents a single SQL statement that
                   4001: ** has been compiled into binary form and is ready to be evaluated.
                   4002: **
                   4003: ** Think of each SQL statement as a separate computer program.  The
1.5       misho    4004: ** original SQL text is source code.  A prepared statement object
1.4       misho    4005: ** is the compiled object code.  All SQL must be converted into a
                   4006: ** prepared statement before it can be run.
1.2       misho    4007: **
1.4       misho    4008: ** The life-cycle of a prepared statement object usually goes like this:
1.2       misho    4009: **
                   4010: ** <ol>
1.4       misho    4011: ** <li> Create the prepared statement object using [sqlite3_prepare_v2()].
                   4012: ** <li> Bind values to [parameters] using the sqlite3_bind_*()
1.2       misho    4013: **      interfaces.
                   4014: ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
1.4       misho    4015: ** <li> Reset the prepared statement using [sqlite3_reset()] then go back
1.2       misho    4016: **      to step 2.  Do this zero or more times.
                   4017: ** <li> Destroy the object using [sqlite3_finalize()].
                   4018: ** </ol>
                   4019: */
                   4020: typedef struct sqlite3_stmt sqlite3_stmt;
                   4021: 
                   4022: /*
                   4023: ** CAPI3REF: Run-time Limits
1.4       misho    4024: ** METHOD: sqlite3
1.2       misho    4025: **
                   4026: ** ^(This interface allows the size of various constructs to be limited
                   4027: ** on a connection by connection basis.  The first parameter is the
                   4028: ** [database connection] whose limit is to be set or queried.  The
                   4029: ** second parameter is one of the [limit categories] that define a
                   4030: ** class of constructs to be size limited.  The third parameter is the
                   4031: ** new limit for that construct.)^
                   4032: **
                   4033: ** ^If the new limit is a negative number, the limit is unchanged.
1.5       misho    4034: ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
1.2       misho    4035: ** [limits | hard upper bound]
                   4036: ** set at compile-time by a C preprocessor macro called
                   4037: ** [limits | SQLITE_MAX_<i>NAME</i>].
                   4038: ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
                   4039: ** ^Attempts to increase a limit above its hard upper bound are
                   4040: ** silently truncated to the hard upper bound.
                   4041: **
1.5       misho    4042: ** ^Regardless of whether or not the limit was changed, the
1.2       misho    4043: ** [sqlite3_limit()] interface returns the prior value of the limit.
                   4044: ** ^Hence, to find the current value of a limit without changing it,
                   4045: ** simply invoke this interface with the third parameter set to -1.
                   4046: **
                   4047: ** Run-time limits are intended for use in applications that manage
                   4048: ** both their own internal database and also databases that are controlled
                   4049: ** by untrusted external sources.  An example application might be a
                   4050: ** web browser that has its own databases for storing history and
                   4051: ** separate databases controlled by JavaScript applications downloaded
                   4052: ** off the Internet.  The internal databases can be given the
                   4053: ** large, default limits.  Databases managed by external sources can
                   4054: ** be given much smaller limits designed to prevent a denial of service
                   4055: ** attack.  Developers might also want to use the [sqlite3_set_authorizer()]
                   4056: ** interface to further control untrusted SQL.  The size of the database
                   4057: ** created by an untrusted script can be contained using the
                   4058: ** [max_page_count] [PRAGMA].
                   4059: **
                   4060: ** New run-time limit categories may be added in future releases.
                   4061: */
                   4062: SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
                   4063: 
                   4064: /*
                   4065: ** CAPI3REF: Run-Time Limit Categories
                   4066: ** KEYWORDS: {limit category} {*limit categories}
                   4067: **
                   4068: ** These constants define various performance limits
                   4069: ** that can be lowered at run-time using [sqlite3_limit()].
                   4070: ** The synopsis of the meanings of the various limits is shown below.
                   4071: ** Additional information is available at [limits | Limits in SQLite].
                   4072: **
                   4073: ** <dl>
                   4074: ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
                   4075: ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
                   4076: **
                   4077: ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
                   4078: ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
                   4079: **
                   4080: ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
                   4081: ** <dd>The maximum number of columns in a table definition or in the
                   4082: ** result set of a [SELECT] or the maximum number of columns in an index
                   4083: ** or in an ORDER BY or GROUP BY clause.</dd>)^
                   4084: **
                   4085: ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
                   4086: ** <dd>The maximum depth of the parse tree on any expression.</dd>)^
                   4087: **
                   4088: ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
                   4089: ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
                   4090: **
                   4091: ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
                   4092: ** <dd>The maximum number of instructions in a virtual machine program
1.5       misho    4093: ** used to implement an SQL statement.  If [sqlite3_prepare_v2()] or
                   4094: ** the equivalent tries to allocate space for more than this many opcodes
                   4095: ** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^
1.2       misho    4096: **
                   4097: ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
                   4098: ** <dd>The maximum number of arguments on a function.</dd>)^
                   4099: **
                   4100: ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
                   4101: ** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
                   4102: **
                   4103: ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
                   4104: ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
                   4105: ** <dd>The maximum length of the pattern argument to the [LIKE] or
                   4106: ** [GLOB] operators.</dd>)^
                   4107: **
                   4108: ** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
                   4109: ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
                   4110: ** <dd>The maximum index number of any [parameter] in an SQL statement.)^
                   4111: **
                   4112: ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
                   4113: ** <dd>The maximum depth of recursion for triggers.</dd>)^
1.4       misho    4114: **
                   4115: ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>
                   4116: ** <dd>The maximum number of auxiliary worker threads that a single
                   4117: ** [prepared statement] may start.</dd>)^
1.2       misho    4118: ** </dl>
                   4119: */
                   4120: #define SQLITE_LIMIT_LENGTH                    0
                   4121: #define SQLITE_LIMIT_SQL_LENGTH                1
                   4122: #define SQLITE_LIMIT_COLUMN                    2
                   4123: #define SQLITE_LIMIT_EXPR_DEPTH                3
                   4124: #define SQLITE_LIMIT_COMPOUND_SELECT           4
                   4125: #define SQLITE_LIMIT_VDBE_OP                   5
                   4126: #define SQLITE_LIMIT_FUNCTION_ARG              6
                   4127: #define SQLITE_LIMIT_ATTACHED                  7
                   4128: #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH       8
                   4129: #define SQLITE_LIMIT_VARIABLE_NUMBER           9
                   4130: #define SQLITE_LIMIT_TRIGGER_DEPTH            10
1.4       misho    4131: #define SQLITE_LIMIT_WORKER_THREADS           11
1.2       misho    4132: 
                   4133: /*
1.5       misho    4134: ** CAPI3REF: Prepare Flags
                   4135: **
                   4136: ** These constants define various flags that can be passed into
                   4137: ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and
                   4138: ** [sqlite3_prepare16_v3()] interfaces.
                   4139: **
                   4140: ** New flags may be added in future releases of SQLite.
                   4141: **
                   4142: ** <dl>
                   4143: ** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt>
                   4144: ** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner
                   4145: ** that the prepared statement will be retained for a long time and
                   4146: ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()]
                   4147: ** and [sqlite3_prepare16_v3()] assume that the prepared statement will
                   4148: ** be used just once or at most a few times and then destroyed using
                   4149: ** [sqlite3_finalize()] relatively soon. The current implementation acts
                   4150: ** on this hint by avoiding the use of [lookaside memory] so as not to
                   4151: ** deplete the limited store of lookaside memory. Future versions of
                   4152: ** SQLite may act on this hint differently.
                   4153: **
                   4154: ** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt>
                   4155: ** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used
                   4156: ** to be required for any prepared statement that wanted to use the
                   4157: ** [sqlite3_normalized_sql()] interface.  However, the
                   4158: ** [sqlite3_normalized_sql()] interface is now available to all
                   4159: ** prepared statements, regardless of whether or not they use this
                   4160: ** flag.
                   4161: **
                   4162: ** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt>
                   4163: ** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler
                   4164: ** to return an error (error code SQLITE_ERROR) if the statement uses
                   4165: ** any virtual tables.
                   4166: ** </dl>
                   4167: */
                   4168: #define SQLITE_PREPARE_PERSISTENT              0x01
                   4169: #define SQLITE_PREPARE_NORMALIZE               0x02
                   4170: #define SQLITE_PREPARE_NO_VTAB                 0x04
                   4171: 
                   4172: /*
1.2       misho    4173: ** CAPI3REF: Compiling An SQL Statement
                   4174: ** KEYWORDS: {SQL statement compiler}
1.4       misho    4175: ** METHOD: sqlite3
                   4176: ** CONSTRUCTOR: sqlite3_stmt
1.2       misho    4177: **
1.5       misho    4178: ** To execute an SQL statement, it must first be compiled into a byte-code
                   4179: ** program using one of these routines.  Or, in other words, these routines
                   4180: ** are constructors for the [prepared statement] object.
                   4181: **
                   4182: ** The preferred routine to use is [sqlite3_prepare_v2()].  The
                   4183: ** [sqlite3_prepare()] interface is legacy and should be avoided.
                   4184: ** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used
                   4185: ** for special purposes.
                   4186: **
                   4187: ** The use of the UTF-8 interfaces is preferred, as SQLite currently
                   4188: ** does all parsing using UTF-8.  The UTF-16 interfaces are provided
                   4189: ** as a convenience.  The UTF-16 interfaces work by converting the
                   4190: ** input text into UTF-8, then invoking the corresponding UTF-8 interface.
1.2       misho    4191: **
                   4192: ** The first argument, "db", is a [database connection] obtained from a
                   4193: ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
                   4194: ** [sqlite3_open16()].  The database connection must not have been closed.
                   4195: **
                   4196: ** The second argument, "zSql", is the statement to be compiled, encoded
1.5       misho    4197: ** as either UTF-8 or UTF-16.  The sqlite3_prepare(), sqlite3_prepare_v2(),
                   4198: ** and sqlite3_prepare_v3()
                   4199: ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(),
                   4200: ** and sqlite3_prepare16_v3() use UTF-16.
1.2       misho    4201: **
1.4       misho    4202: ** ^If the nByte argument is negative, then zSql is read up to the
                   4203: ** first zero terminator. ^If nByte is positive, then it is the
                   4204: ** number of bytes read from zSql.  ^If nByte is zero, then no prepared
                   4205: ** statement is generated.
                   4206: ** If the caller knows that the supplied string is nul-terminated, then
                   4207: ** there is a small performance advantage to passing an nByte parameter that
                   4208: ** is the number of bytes in the input string <i>including</i>
                   4209: ** the nul-terminator.
1.2       misho    4210: **
                   4211: ** ^If pzTail is not NULL then *pzTail is made to point to the first byte
                   4212: ** past the end of the first SQL statement in zSql.  These routines only
                   4213: ** compile the first statement in zSql, so *pzTail is left pointing to
                   4214: ** what remains uncompiled.
                   4215: **
                   4216: ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
                   4217: ** executed using [sqlite3_step()].  ^If there is an error, *ppStmt is set
                   4218: ** to NULL.  ^If the input text contains no SQL (if the input is an empty
                   4219: ** string or a comment) then *ppStmt is set to NULL.
                   4220: ** The calling procedure is responsible for deleting the compiled
                   4221: ** SQL statement using [sqlite3_finalize()] after it has finished with it.
                   4222: ** ppStmt may not be NULL.
                   4223: **
                   4224: ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
                   4225: ** otherwise an [error code] is returned.
                   4226: **
1.5       misho    4227: ** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(),
                   4228: ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs.
                   4229: ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16())
                   4230: ** are retained for backwards compatibility, but their use is discouraged.
                   4231: ** ^In the "vX" interfaces, the prepared statement
1.2       misho    4232: ** that is returned (the [sqlite3_stmt] object) contains a copy of the
                   4233: ** original SQL text. This causes the [sqlite3_step()] interface to
                   4234: ** behave differently in three ways:
                   4235: **
                   4236: ** <ol>
                   4237: ** <li>
                   4238: ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
                   4239: ** always used to do, [sqlite3_step()] will automatically recompile the SQL
1.4       misho    4240: ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
                   4241: ** retries will occur before sqlite3_step() gives up and returns an error.
1.2       misho    4242: ** </li>
                   4243: **
                   4244: ** <li>
                   4245: ** ^When an error occurs, [sqlite3_step()] will return one of the detailed
                   4246: ** [error codes] or [extended error codes].  ^The legacy behavior was that
                   4247: ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
                   4248: ** and the application would have to make a second call to [sqlite3_reset()]
                   4249: ** in order to find the underlying cause of the problem. With the "v2" prepare
                   4250: ** interfaces, the underlying reason for the error is returned immediately.
                   4251: ** </li>
                   4252: **
                   4253: ** <li>
1.5       misho    4254: ** ^If the specific value bound to a [parameter | host parameter] in the
1.2       misho    4255: ** WHERE clause might influence the choice of query plan for a statement,
1.5       misho    4256: ** then the statement will be automatically recompiled, as if there had been
                   4257: ** a schema change, on the first [sqlite3_step()] call following any change
                   4258: ** to the [sqlite3_bind_text | bindings] of that [parameter].
                   4259: ** ^The specific value of a WHERE-clause [parameter] might influence the
1.2       misho    4260: ** choice of query plan if the parameter is the left-hand side of a [LIKE]
                   4261: ** or [GLOB] operator or if the parameter is compared to an indexed column
1.5       misho    4262: ** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled.
1.2       misho    4263: ** </li>
                   4264: ** </ol>
1.5       misho    4265: **
                   4266: ** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having
                   4267: ** the extra prepFlags parameter, which is a bit array consisting of zero or
                   4268: ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags.  ^The
                   4269: ** sqlite3_prepare_v2() interface works exactly the same as
                   4270: ** sqlite3_prepare_v3() with a zero prepFlags parameter.
1.2       misho    4271: */
                   4272: SQLITE_API int sqlite3_prepare(
                   4273:   sqlite3 *db,            /* Database handle */
                   4274:   const char *zSql,       /* SQL statement, UTF-8 encoded */
                   4275:   int nByte,              /* Maximum length of zSql in bytes. */
                   4276:   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
                   4277:   const char **pzTail     /* OUT: Pointer to unused portion of zSql */
                   4278: );
                   4279: SQLITE_API int sqlite3_prepare_v2(
                   4280:   sqlite3 *db,            /* Database handle */
                   4281:   const char *zSql,       /* SQL statement, UTF-8 encoded */
                   4282:   int nByte,              /* Maximum length of zSql in bytes. */
                   4283:   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
                   4284:   const char **pzTail     /* OUT: Pointer to unused portion of zSql */
                   4285: );
1.5       misho    4286: SQLITE_API int sqlite3_prepare_v3(
                   4287:   sqlite3 *db,            /* Database handle */
                   4288:   const char *zSql,       /* SQL statement, UTF-8 encoded */
                   4289:   int nByte,              /* Maximum length of zSql in bytes. */
                   4290:   unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
                   4291:   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
                   4292:   const char **pzTail     /* OUT: Pointer to unused portion of zSql */
                   4293: );
1.2       misho    4294: SQLITE_API int sqlite3_prepare16(
                   4295:   sqlite3 *db,            /* Database handle */
                   4296:   const void *zSql,       /* SQL statement, UTF-16 encoded */
                   4297:   int nByte,              /* Maximum length of zSql in bytes. */
                   4298:   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
                   4299:   const void **pzTail     /* OUT: Pointer to unused portion of zSql */
                   4300: );
                   4301: SQLITE_API int sqlite3_prepare16_v2(
                   4302:   sqlite3 *db,            /* Database handle */
                   4303:   const void *zSql,       /* SQL statement, UTF-16 encoded */
                   4304:   int nByte,              /* Maximum length of zSql in bytes. */
                   4305:   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
                   4306:   const void **pzTail     /* OUT: Pointer to unused portion of zSql */
                   4307: );
1.5       misho    4308: SQLITE_API int sqlite3_prepare16_v3(
                   4309:   sqlite3 *db,            /* Database handle */
                   4310:   const void *zSql,       /* SQL statement, UTF-16 encoded */
                   4311:   int nByte,              /* Maximum length of zSql in bytes. */
                   4312:   unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */
                   4313:   sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
                   4314:   const void **pzTail     /* OUT: Pointer to unused portion of zSql */
                   4315: );
1.2       misho    4316: 
                   4317: /*
                   4318: ** CAPI3REF: Retrieving Statement SQL
1.4       misho    4319: ** METHOD: sqlite3_stmt
1.2       misho    4320: **
1.4       misho    4321: ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8
                   4322: ** SQL text used to create [prepared statement] P if P was
1.5       misho    4323: ** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()],
                   4324: ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
1.4       misho    4325: ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8
                   4326: ** string containing the SQL text of prepared statement P with
                   4327: ** [bound parameters] expanded.
1.5       misho    4328: ** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8
                   4329: ** string containing the normalized SQL text of prepared statement P.  The
                   4330: ** semantics used to normalize a SQL statement are unspecified and subject
                   4331: ** to change.  At a minimum, literal values will be replaced with suitable
                   4332: ** placeholders.
1.4       misho    4333: **
                   4334: ** ^(For example, if a prepared statement is created using the SQL
                   4335: ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345
                   4336: ** and parameter :xyz is unbound, then sqlite3_sql() will return
                   4337: ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()
                   4338: ** will return "SELECT 2345,NULL".)^
                   4339: **
                   4340: ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory
                   4341: ** is available to hold the result, or if the result would exceed the
                   4342: ** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].
                   4343: **
                   4344: ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of
                   4345: ** bound parameter expansions.  ^The [SQLITE_OMIT_TRACE] compile-time
                   4346: ** option causes sqlite3_expanded_sql() to always return NULL.
                   4347: **
1.5       misho    4348: ** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P)
                   4349: ** are managed by SQLite and are automatically freed when the prepared
                   4350: ** statement is finalized.
1.4       misho    4351: ** ^The string returned by sqlite3_expanded_sql(P), on the other hand,
1.6.2.1 ! misho    4352: ** is obtained from [sqlite3_malloc()] and must be freed by the application
1.4       misho    4353: ** by passing it to [sqlite3_free()].
1.6.2.1 ! misho    4354: **
        !          4355: ** ^The sqlite3_normalized_sql() interface is only available if
        !          4356: ** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined.
1.2       misho    4357: */
                   4358: SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
1.4       misho    4359: SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt);
1.6.2.1 ! misho    4360: #ifdef SQLITE_ENABLE_NORMALIZE
1.5       misho    4361: SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt);
1.6.2.1 ! misho    4362: #endif
1.2       misho    4363: 
                   4364: /*
                   4365: ** CAPI3REF: Determine If An SQL Statement Writes The Database
1.4       misho    4366: ** METHOD: sqlite3_stmt
1.2       misho    4367: **
                   4368: ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
                   4369: ** and only if the [prepared statement] X makes no direct changes to
                   4370: ** the content of the database file.
                   4371: **
                   4372: ** Note that [application-defined SQL functions] or
1.5       misho    4373: ** [virtual tables] might change the database indirectly as a side effect.
                   4374: ** ^(For example, if an application defines a function "eval()" that
1.2       misho    4375: ** calls [sqlite3_exec()], then the following SQL statement would
                   4376: ** change the database file through side-effects:
                   4377: **
                   4378: ** <blockquote><pre>
                   4379: **    SELECT eval('DELETE FROM t1') FROM t2;
                   4380: ** </pre></blockquote>
                   4381: **
                   4382: ** But because the [SELECT] statement does not change the database file
                   4383: ** directly, sqlite3_stmt_readonly() would still return true.)^
                   4384: **
                   4385: ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
                   4386: ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
                   4387: ** since the statements themselves do not actually modify the database but
1.5       misho    4388: ** rather they control the timing of when other statements modify the
1.2       misho    4389: ** database.  ^The [ATTACH] and [DETACH] statements also cause
                   4390: ** sqlite3_stmt_readonly() to return true since, while those statements
1.5       misho    4391: ** change the configuration of a database connection, they do not make
1.2       misho    4392: ** changes to the content of the database files on disk.
1.5       misho    4393: ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since
                   4394: ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and
                   4395: ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so
                   4396: ** sqlite3_stmt_readonly() returns false for those commands.
1.6.2.1 ! misho    4397: **
        !          4398: ** ^This routine returns false if there is any possibility that the
        !          4399: ** statement might change the database file.  ^A false return does
        !          4400: ** not guarantee that the statement will change the database file.
        !          4401: ** ^For example, an UPDATE statement might have a WHERE clause that
        !          4402: ** makes it a no-op, but the sqlite3_stmt_readonly() result would still
        !          4403: ** be false.  ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a
        !          4404: ** read-only no-op if the table already exists, but
        !          4405: ** sqlite3_stmt_readonly() still returns false for such a statement.
        !          4406: **
        !          4407: ** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN]
        !          4408: ** statement, then sqlite3_stmt_readonly(X) returns the same value as
        !          4409: ** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted.
1.2       misho    4410: */
                   4411: SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
                   4412: 
                   4413: /*
1.5       misho    4414: ** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement
                   4415: ** METHOD: sqlite3_stmt
                   4416: **
                   4417: ** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the
                   4418: ** prepared statement S is an EXPLAIN statement, or 2 if the
                   4419: ** statement S is an EXPLAIN QUERY PLAN.
                   4420: ** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is
                   4421: ** an ordinary statement or a NULL pointer.
                   4422: */
                   4423: SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt);
                   4424: 
                   4425: /*
1.6.2.1 ! misho    4426: ** CAPI3REF: Change The EXPLAIN Setting For A Prepared Statement
        !          4427: ** METHOD: sqlite3_stmt
        !          4428: **
        !          4429: ** The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN
        !          4430: ** setting for [prepared statement] S.  If E is zero, then S becomes
        !          4431: ** a normal prepared statement.  If E is 1, then S behaves as if
        !          4432: ** its SQL text began with "[EXPLAIN]".  If E is 2, then S behaves as if
        !          4433: ** its SQL text began with "[EXPLAIN QUERY PLAN]".
        !          4434: **
        !          4435: ** Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared.
        !          4436: ** SQLite tries to avoid a reprepare, but a reprepare might be necessary
        !          4437: ** on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode.
        !          4438: **
        !          4439: ** Because of the potential need to reprepare, a call to
        !          4440: ** sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be
        !          4441: ** reprepared because it was created using [sqlite3_prepare()] instead of
        !          4442: ** the newer [sqlite3_prepare_v2()] or [sqlite3_prepare_v3()] interfaces and
        !          4443: ** hence has no saved SQL text with which to reprepare.
        !          4444: **
        !          4445: ** Changing the explain setting for a prepared statement does not change
        !          4446: ** the original SQL text for the statement.  Hence, if the SQL text originally
        !          4447: ** began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0)
        !          4448: ** is called to convert the statement into an ordinary statement, the EXPLAIN
        !          4449: ** or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S)
        !          4450: ** output, even though the statement now acts like a normal SQL statement.
        !          4451: **
        !          4452: ** This routine returns SQLITE_OK if the explain mode is successfully
        !          4453: ** changed, or an error code if the explain mode could not be changed.
        !          4454: ** The explain mode cannot be changed while a statement is active.
        !          4455: ** Hence, it is good practice to call [sqlite3_reset(S)]
        !          4456: ** immediately prior to calling sqlite3_stmt_explain(S,E).
        !          4457: */
        !          4458: SQLITE_API int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode);
        !          4459: 
        !          4460: /*
1.2       misho    4461: ** CAPI3REF: Determine If A Prepared Statement Has Been Reset
1.4       misho    4462: ** METHOD: sqlite3_stmt
1.2       misho    4463: **
                   4464: ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
1.5       misho    4465: ** [prepared statement] S has been stepped at least once using
1.4       misho    4466: ** [sqlite3_step(S)] but has neither run to completion (returned
                   4467: ** [SQLITE_DONE] from [sqlite3_step(S)]) nor
1.2       misho    4468: ** been reset using [sqlite3_reset(S)].  ^The sqlite3_stmt_busy(S)
1.5       misho    4469: ** interface returns false if S is a NULL pointer.  If S is not a
1.2       misho    4470: ** NULL pointer and is not a pointer to a valid [prepared statement]
                   4471: ** object, then the behavior is undefined and probably undesirable.
                   4472: **
                   4473: ** This interface can be used in combination [sqlite3_next_stmt()]
1.5       misho    4474: ** to locate all prepared statements associated with a database
1.2       misho    4475: ** connection that are in need of being reset.  This can be used,
1.5       misho    4476: ** for example, in diagnostic routines to search for prepared
1.2       misho    4477: ** statements that are holding a transaction open.
                   4478: */
                   4479: SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
                   4480: 
                   4481: /*
                   4482: ** CAPI3REF: Dynamically Typed Value Object
                   4483: ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
                   4484: **
                   4485: ** SQLite uses the sqlite3_value object to represent all values
                   4486: ** that can be stored in a database table. SQLite uses dynamic typing
                   4487: ** for the values it stores.  ^Values stored in sqlite3_value objects
                   4488: ** can be integers, floating point values, strings, BLOBs, or NULL.
                   4489: **
                   4490: ** An sqlite3_value object may be either "protected" or "unprotected".
                   4491: ** Some interfaces require a protected sqlite3_value.  Other interfaces
                   4492: ** will accept either a protected or an unprotected sqlite3_value.
                   4493: ** Every interface that accepts sqlite3_value arguments specifies
1.4       misho    4494: ** whether or not it requires a protected sqlite3_value.  The
1.5       misho    4495: ** [sqlite3_value_dup()] interface can be used to construct a new
1.4       misho    4496: ** protected sqlite3_value from an unprotected sqlite3_value.
1.2       misho    4497: **
                   4498: ** The terms "protected" and "unprotected" refer to whether or not
                   4499: ** a mutex is held.  An internal mutex is held for a protected
                   4500: ** sqlite3_value object but no mutex is held for an unprotected
                   4501: ** sqlite3_value object.  If SQLite is compiled to be single-threaded
                   4502: ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
1.5       misho    4503: ** or if SQLite is run in one of reduced mutex modes
1.2       misho    4504: ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
                   4505: ** then there is no distinction between protected and unprotected
                   4506: ** sqlite3_value objects and they can be used interchangeably.  However,
                   4507: ** for maximum code portability it is recommended that applications
                   4508: ** still make the distinction between protected and unprotected
                   4509: ** sqlite3_value objects even when not strictly required.
                   4510: **
                   4511: ** ^The sqlite3_value objects that are passed as parameters into the
                   4512: ** implementation of [application-defined SQL functions] are protected.
1.6.2.1 ! misho    4513: ** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()]
        !          4514: ** are protected.
1.2       misho    4515: ** ^The sqlite3_value object returned by
                   4516: ** [sqlite3_column_value()] is unprotected.
1.5       misho    4517: ** Unprotected sqlite3_value objects may only be used as arguments
                   4518: ** to [sqlite3_result_value()], [sqlite3_bind_value()], and
                   4519: ** [sqlite3_value_dup()].
1.2       misho    4520: ** The [sqlite3_value_blob | sqlite3_value_type()] family of
                   4521: ** interfaces require protected sqlite3_value objects.
                   4522: */
1.5       misho    4523: typedef struct sqlite3_value sqlite3_value;
1.2       misho    4524: 
                   4525: /*
                   4526: ** CAPI3REF: SQL Function Context Object
                   4527: **
                   4528: ** The context in which an SQL function executes is stored in an
                   4529: ** sqlite3_context object.  ^A pointer to an sqlite3_context object
                   4530: ** is always first parameter to [application-defined SQL functions].
                   4531: ** The application-defined SQL function implementation will pass this
                   4532: ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
                   4533: ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
                   4534: ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
                   4535: ** and/or [sqlite3_set_auxdata()].
                   4536: */
                   4537: typedef struct sqlite3_context sqlite3_context;
                   4538: 
                   4539: /*
                   4540: ** CAPI3REF: Binding Values To Prepared Statements
                   4541: ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
                   4542: ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
1.4       misho    4543: ** METHOD: sqlite3_stmt
1.2       misho    4544: **
                   4545: ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
                   4546: ** literals may be replaced by a [parameter] that matches one of following
                   4547: ** templates:
                   4548: **
                   4549: ** <ul>
                   4550: ** <li>  ?
                   4551: ** <li>  ?NNN
                   4552: ** <li>  :VVV
                   4553: ** <li>  @VVV
                   4554: ** <li>  $VVV
                   4555: ** </ul>
                   4556: **
                   4557: ** In the templates above, NNN represents an integer literal,
                   4558: ** and VVV represents an alphanumeric identifier.)^  ^The values of these
                   4559: ** parameters (also called "host parameter names" or "SQL parameters")
                   4560: ** can be set using the sqlite3_bind_*() routines defined here.
                   4561: **
                   4562: ** ^The first argument to the sqlite3_bind_*() routines is always
                   4563: ** a pointer to the [sqlite3_stmt] object returned from
                   4564: ** [sqlite3_prepare_v2()] or its variants.
                   4565: **
                   4566: ** ^The second argument is the index of the SQL parameter to be set.
                   4567: ** ^The leftmost SQL parameter has an index of 1.  ^When the same named
                   4568: ** SQL parameter is used more than once, second and subsequent
                   4569: ** occurrences have the same index as the first occurrence.
                   4570: ** ^The index for named parameters can be looked up using the
                   4571: ** [sqlite3_bind_parameter_index()] API if desired.  ^The index
                   4572: ** for "?NNN" parameters is the value of NNN.
                   4573: ** ^The NNN value must be between 1 and the [sqlite3_limit()]
1.5       misho    4574: ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766).
1.2       misho    4575: **
                   4576: ** ^The third argument is the value to bind to the parameter.
1.4       misho    4577: ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
                   4578: ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
                   4579: ** is ignored and the end result is the same as sqlite3_bind_null().
1.5       misho    4580: ** ^If the third parameter to sqlite3_bind_text() is not NULL, then
                   4581: ** it should be a pointer to well-formed UTF8 text.
                   4582: ** ^If the third parameter to sqlite3_bind_text16() is not NULL, then
                   4583: ** it should be a pointer to well-formed UTF16 text.
                   4584: ** ^If the third parameter to sqlite3_bind_text64() is not NULL, then
                   4585: ** it should be a pointer to a well-formed unicode string that is
                   4586: ** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16
                   4587: ** otherwise.
                   4588: **
                   4589: ** [[byte-order determination rules]] ^The byte-order of
                   4590: ** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF)
                   4591: ** found in first character, which is removed, or in the absence of a BOM
                   4592: ** the byte order is the native byte order of the host
                   4593: ** machine for sqlite3_bind_text16() or the byte order specified in
                   4594: ** the 6th parameter for sqlite3_bind_text64().)^
                   4595: ** ^If UTF16 input text contains invalid unicode
                   4596: ** characters, then SQLite might change those invalid characters
                   4597: ** into the unicode replacement character: U+FFFD.
1.2       misho    4598: **
                   4599: ** ^(In those routines that have a fourth argument, its value is the
                   4600: ** number of bytes in the parameter.  To be clear: the value is the
                   4601: ** number of <u>bytes</u> in the value, not the number of characters.)^
1.3       misho    4602: ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
                   4603: ** is negative, then the length of the string is
1.2       misho    4604: ** the number of bytes up to the first zero terminator.
1.3       misho    4605: ** If the fourth parameter to sqlite3_bind_blob() is negative, then
                   4606: ** the behavior is undefined.
1.2       misho    4607: ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
1.4       misho    4608: ** or sqlite3_bind_text16() or sqlite3_bind_text64() then
                   4609: ** that parameter must be the byte offset
1.2       misho    4610: ** where the NUL terminator would occur assuming the string were NUL
1.5       misho    4611: ** terminated.  If any NUL characters occurs at byte offsets less than
1.2       misho    4612: ** the value of the fourth parameter then the resulting string value will
                   4613: ** contain embedded NULs.  The result of expressions involving strings
                   4614: ** with embedded NULs is undefined.
                   4615: **
1.6.2.1 ! misho    4616: ** ^The fifth argument to the BLOB and string binding interfaces controls
        !          4617: ** or indicates the lifetime of the object referenced by the third parameter.
        !          4618: ** These three options exist:
        !          4619: ** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished
        !          4620: ** with it may be passed. ^It is called to dispose of the BLOB or string even
        !          4621: ** if the call to the bind API fails, except the destructor is not called if
        !          4622: ** the third parameter is a NULL pointer or the fourth parameter is negative.
        !          4623: ** ^ (2) The special constant, [SQLITE_STATIC], may be passed to indicate that
        !          4624: ** the application remains responsible for disposing of the object. ^In this
        !          4625: ** case, the object and the provided pointer to it must remain valid until
        !          4626: ** either the prepared statement is finalized or the same SQL parameter is
        !          4627: ** bound to something else, whichever occurs sooner.
        !          4628: ** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the
        !          4629: ** object is to be copied prior to the return from sqlite3_bind_*(). ^The
        !          4630: ** object and pointer to it must remain valid until then. ^SQLite will then
        !          4631: ** manage the lifetime of its private copy.
1.2       misho    4632: **
1.4       misho    4633: ** ^The sixth argument to sqlite3_bind_text64() must be one of
                   4634: ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]
                   4635: ** to specify the encoding of the text in the third parameter.  If
                   4636: ** the sixth argument to sqlite3_bind_text64() is not one of the
                   4637: ** allowed values shown above, or if the text encoding is different
                   4638: ** from the encoding specified by the sixth parameter, then the behavior
                   4639: ** is undefined.
                   4640: **
1.2       misho    4641: ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
                   4642: ** is filled with zeroes.  ^A zeroblob uses a fixed amount of memory
                   4643: ** (just an integer to hold its size) while it is being processed.
                   4644: ** Zeroblobs are intended to serve as placeholders for BLOBs whose
                   4645: ** content is later written using
                   4646: ** [sqlite3_blob_open | incremental BLOB I/O] routines.
                   4647: ** ^A negative value for the zeroblob results in a zero-length BLOB.
                   4648: **
1.5       misho    4649: ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in
                   4650: ** [prepared statement] S to have an SQL value of NULL, but to also be
                   4651: ** associated with the pointer P of type T.  ^D is either a NULL pointer or
                   4652: ** a pointer to a destructor function for P. ^SQLite will invoke the
                   4653: ** destructor D with a single argument of P when it is finished using
                   4654: ** P.  The T parameter should be a static string, preferably a string
                   4655: ** literal. The sqlite3_bind_pointer() routine is part of the
                   4656: ** [pointer passing interface] added for SQLite 3.20.0.
                   4657: **
1.2       misho    4658: ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
                   4659: ** for the [prepared statement] or with a prepared statement for which
                   4660: ** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
                   4661: ** then the call will return [SQLITE_MISUSE].  If any sqlite3_bind_()
                   4662: ** routine is passed a [prepared statement] that has been finalized, the
                   4663: ** result is undefined and probably harmful.
                   4664: **
                   4665: ** ^Bindings are not cleared by the [sqlite3_reset()] routine.
                   4666: ** ^Unbound parameters are interpreted as NULL.
                   4667: **
                   4668: ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
                   4669: ** [error code] if anything goes wrong.
1.4       misho    4670: ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB
                   4671: ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or
                   4672: ** [SQLITE_MAX_LENGTH].
1.2       misho    4673: ** ^[SQLITE_RANGE] is returned if the parameter
                   4674: ** index is out of range.  ^[SQLITE_NOMEM] is returned if malloc() fails.
                   4675: **
                   4676: ** See also: [sqlite3_bind_parameter_count()],
                   4677: ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
                   4678: */
                   4679: SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
1.4       misho    4680: SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64,
                   4681:                         void(*)(void*));
1.2       misho    4682: SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
                   4683: SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
                   4684: SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
                   4685: SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
1.4       misho    4686: SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*));
1.2       misho    4687: SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
1.4       misho    4688: SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64,
                   4689:                          void(*)(void*), unsigned char encoding);
1.2       misho    4690: SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
1.5       misho    4691: SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*));
1.2       misho    4692: SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
1.4       misho    4693: SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64);
1.2       misho    4694: 
                   4695: /*
                   4696: ** CAPI3REF: Number Of SQL Parameters
1.4       misho    4697: ** METHOD: sqlite3_stmt
1.2       misho    4698: **
                   4699: ** ^This routine can be used to find the number of [SQL parameters]
                   4700: ** in a [prepared statement].  SQL parameters are tokens of the
                   4701: ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
                   4702: ** placeholders for values that are [sqlite3_bind_blob | bound]
                   4703: ** to the parameters at a later time.
                   4704: **
                   4705: ** ^(This routine actually returns the index of the largest (rightmost)
                   4706: ** parameter. For all forms except ?NNN, this will correspond to the
                   4707: ** number of unique parameters.  If parameters of the ?NNN form are used,
                   4708: ** there may be gaps in the list.)^
                   4709: **
                   4710: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
                   4711: ** [sqlite3_bind_parameter_name()], and
                   4712: ** [sqlite3_bind_parameter_index()].
                   4713: */
                   4714: SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
                   4715: 
                   4716: /*
                   4717: ** CAPI3REF: Name Of A Host Parameter
1.4       misho    4718: ** METHOD: sqlite3_stmt
1.2       misho    4719: **
                   4720: ** ^The sqlite3_bind_parameter_name(P,N) interface returns
                   4721: ** the name of the N-th [SQL parameter] in the [prepared statement] P.
                   4722: ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
                   4723: ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
                   4724: ** respectively.
                   4725: ** In other words, the initial ":" or "$" or "@" or "?"
                   4726: ** is included as part of the name.)^
                   4727: ** ^Parameters of the form "?" without a following integer have no name
                   4728: ** and are referred to as "nameless" or "anonymous parameters".
                   4729: **
                   4730: ** ^The first host parameter has an index of 1, not 0.
                   4731: **
                   4732: ** ^If the value N is out of range or if the N-th parameter is
                   4733: ** nameless, then NULL is returned.  ^The returned string is
                   4734: ** always in UTF-8 encoding even if the named parameter was
1.5       misho    4735: ** originally specified as UTF-16 in [sqlite3_prepare16()],
                   4736: ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()].
1.2       misho    4737: **
                   4738: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
                   4739: ** [sqlite3_bind_parameter_count()], and
                   4740: ** [sqlite3_bind_parameter_index()].
                   4741: */
                   4742: SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
                   4743: 
                   4744: /*
                   4745: ** CAPI3REF: Index Of A Parameter With A Given Name
1.4       misho    4746: ** METHOD: sqlite3_stmt
1.2       misho    4747: **
                   4748: ** ^Return the index of an SQL parameter given its name.  ^The
                   4749: ** index value returned is suitable for use as the second
                   4750: ** parameter to [sqlite3_bind_blob|sqlite3_bind()].  ^A zero
                   4751: ** is returned if no matching parameter is found.  ^The parameter
                   4752: ** name must be given in UTF-8 even if the original statement
1.5       misho    4753: ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or
                   4754: ** [sqlite3_prepare16_v3()].
1.2       misho    4755: **
                   4756: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
                   4757: ** [sqlite3_bind_parameter_count()], and
1.4       misho    4758: ** [sqlite3_bind_parameter_name()].
1.2       misho    4759: */
                   4760: SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
                   4761: 
                   4762: /*
                   4763: ** CAPI3REF: Reset All Bindings On A Prepared Statement
1.4       misho    4764: ** METHOD: sqlite3_stmt
1.2       misho    4765: **
                   4766: ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
                   4767: ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
                   4768: ** ^Use this routine to reset all host parameters to NULL.
                   4769: */
                   4770: SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
                   4771: 
                   4772: /*
                   4773: ** CAPI3REF: Number Of Columns In A Result Set
1.4       misho    4774: ** METHOD: sqlite3_stmt
1.2       misho    4775: **
                   4776: ** ^Return the number of columns in the result set returned by the
1.5       misho    4777: ** [prepared statement]. ^If this routine returns 0, that means the
                   4778: ** [prepared statement] returns no data (for example an [UPDATE]).
                   4779: ** ^However, just because this routine returns a positive number does not
                   4780: ** mean that one or more rows of data will be returned.  ^A SELECT statement
                   4781: ** will always have a positive sqlite3_column_count() but depending on the
                   4782: ** WHERE clause constraints and the table content, it might return no rows.
1.2       misho    4783: **
                   4784: ** See also: [sqlite3_data_count()]
                   4785: */
                   4786: SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
                   4787: 
                   4788: /*
                   4789: ** CAPI3REF: Column Names In A Result Set
1.4       misho    4790: ** METHOD: sqlite3_stmt
1.2       misho    4791: **
                   4792: ** ^These routines return the name assigned to a particular column
                   4793: ** in the result set of a [SELECT] statement.  ^The sqlite3_column_name()
                   4794: ** interface returns a pointer to a zero-terminated UTF-8 string
                   4795: ** and sqlite3_column_name16() returns a pointer to a zero-terminated
                   4796: ** UTF-16 string.  ^The first parameter is the [prepared statement]
                   4797: ** that implements the [SELECT] statement. ^The second parameter is the
                   4798: ** column number.  ^The leftmost column is number 0.
                   4799: **
                   4800: ** ^The returned string pointer is valid until either the [prepared statement]
                   4801: ** is destroyed by [sqlite3_finalize()] or until the statement is automatically
                   4802: ** reprepared by the first call to [sqlite3_step()] for a particular run
                   4803: ** or until the next call to
                   4804: ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
                   4805: **
                   4806: ** ^If sqlite3_malloc() fails during the processing of either routine
                   4807: ** (for example during a conversion from UTF-8 to UTF-16) then a
                   4808: ** NULL pointer is returned.
                   4809: **
                   4810: ** ^The name of a result column is the value of the "AS" clause for
                   4811: ** that column, if there is an AS clause.  If there is no AS clause
                   4812: ** then the name of the column is unspecified and may change from
                   4813: ** one release of SQLite to the next.
                   4814: */
                   4815: SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
                   4816: SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
                   4817: 
                   4818: /*
                   4819: ** CAPI3REF: Source Of Data In A Query Result
1.4       misho    4820: ** METHOD: sqlite3_stmt
1.2       misho    4821: **
                   4822: ** ^These routines provide a means to determine the database, table, and
                   4823: ** table column that is the origin of a particular result column in
                   4824: ** [SELECT] statement.
                   4825: ** ^The name of the database or table or column can be returned as
                   4826: ** either a UTF-8 or UTF-16 string.  ^The _database_ routines return
                   4827: ** the database name, the _table_ routines return the table name, and
                   4828: ** the origin_ routines return the column name.
                   4829: ** ^The returned string is valid until the [prepared statement] is destroyed
                   4830: ** using [sqlite3_finalize()] or until the statement is automatically
                   4831: ** reprepared by the first call to [sqlite3_step()] for a particular run
                   4832: ** or until the same information is requested
                   4833: ** again in a different encoding.
                   4834: **
                   4835: ** ^The names returned are the original un-aliased names of the
                   4836: ** database, table, and column.
                   4837: **
                   4838: ** ^The first argument to these interfaces is a [prepared statement].
                   4839: ** ^These functions return information about the Nth result column returned by
                   4840: ** the statement, where N is the second function argument.
                   4841: ** ^The left-most column is column 0 for these routines.
                   4842: **
                   4843: ** ^If the Nth column returned by the statement is an expression or
                   4844: ** subquery and is not a column value, then all of these functions return
1.5       misho    4845: ** NULL.  ^These routines might also return NULL if a memory allocation error
1.2       misho    4846: ** occurs.  ^Otherwise, they return the name of the attached database, table,
                   4847: ** or column that query result column was extracted from.
                   4848: **
                   4849: ** ^As with all other SQLite APIs, those whose names end with "16" return
                   4850: ** UTF-16 encoded strings and the other functions return UTF-8.
                   4851: **
                   4852: ** ^These APIs are only available if the library was compiled with the
                   4853: ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
                   4854: **
                   4855: ** If two or more threads call one or more
                   4856: ** [sqlite3_column_database_name | column metadata interfaces]
                   4857: ** for the same [prepared statement] and result column
                   4858: ** at the same time then the results are undefined.
                   4859: */
                   4860: SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
                   4861: SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
                   4862: SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
                   4863: SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
                   4864: SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
                   4865: SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
                   4866: 
                   4867: /*
                   4868: ** CAPI3REF: Declared Datatype Of A Query Result
1.4       misho    4869: ** METHOD: sqlite3_stmt
1.2       misho    4870: **
                   4871: ** ^(The first parameter is a [prepared statement].
                   4872: ** If this statement is a [SELECT] statement and the Nth column of the
                   4873: ** returned result set of that [SELECT] is a table column (not an
                   4874: ** expression or subquery) then the declared type of the table
                   4875: ** column is returned.)^  ^If the Nth column of the result set is an
                   4876: ** expression or subquery, then a NULL pointer is returned.
                   4877: ** ^The returned string is always UTF-8 encoded.
                   4878: **
                   4879: ** ^(For example, given the database schema:
                   4880: **
                   4881: ** CREATE TABLE t1(c1 VARIANT);
                   4882: **
                   4883: ** and the following statement to be compiled:
                   4884: **
                   4885: ** SELECT c1 + 1, c1 FROM t1;
                   4886: **
                   4887: ** this routine would return the string "VARIANT" for the second result
                   4888: ** column (i==1), and a NULL pointer for the first result column (i==0).)^
                   4889: **
                   4890: ** ^SQLite uses dynamic run-time typing.  ^So just because a column
                   4891: ** is declared to contain a particular type does not mean that the
                   4892: ** data stored in that column is of the declared type.  SQLite is
                   4893: ** strongly typed, but the typing is dynamic not static.  ^Type
                   4894: ** is associated with individual values, not with the containers
                   4895: ** used to hold those values.
                   4896: */
                   4897: SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
                   4898: SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
                   4899: 
                   4900: /*
                   4901: ** CAPI3REF: Evaluate An SQL Statement
1.4       misho    4902: ** METHOD: sqlite3_stmt
1.2       misho    4903: **
1.5       misho    4904: ** After a [prepared statement] has been prepared using any of
                   4905: ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()],
                   4906: ** or [sqlite3_prepare16_v3()] or one of the legacy
1.2       misho    4907: ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
                   4908: ** must be called one or more times to evaluate the statement.
                   4909: **
                   4910: ** The details of the behavior of the sqlite3_step() interface depend
1.5       misho    4911: ** on whether the statement was prepared using the newer "vX" interfaces
                   4912: ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()],
                   4913: ** [sqlite3_prepare16_v2()] or the older legacy
                   4914: ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()].  The use of the
                   4915: ** new "vX" interface is recommended for new applications but the legacy
1.2       misho    4916: ** interface will continue to be supported.
                   4917: **
                   4918: ** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
                   4919: ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
                   4920: ** ^With the "v2" interface, any of the other [result codes] or
                   4921: ** [extended result codes] might be returned as well.
                   4922: **
                   4923: ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
                   4924: ** database locks it needs to do its job.  ^If the statement is a [COMMIT]
                   4925: ** or occurs outside of an explicit transaction, then you can retry the
                   4926: ** statement.  If the statement is not a [COMMIT] and occurs within an
                   4927: ** explicit transaction then you should rollback the transaction before
                   4928: ** continuing.
                   4929: **
                   4930: ** ^[SQLITE_DONE] means that the statement has finished executing
                   4931: ** successfully.  sqlite3_step() should not be called again on this virtual
                   4932: ** machine without first calling [sqlite3_reset()] to reset the virtual
                   4933: ** machine back to its initial state.
                   4934: **
                   4935: ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
                   4936: ** is returned each time a new row of data is ready for processing by the
                   4937: ** caller. The values may be accessed using the [column access functions].
                   4938: ** sqlite3_step() is called again to retrieve the next row of data.
                   4939: **
                   4940: ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
                   4941: ** violation) has occurred.  sqlite3_step() should not be called again on
                   4942: ** the VM. More information may be found by calling [sqlite3_errmsg()].
                   4943: ** ^With the legacy interface, a more specific error code (for example,
                   4944: ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
                   4945: ** can be obtained by calling [sqlite3_reset()] on the
                   4946: ** [prepared statement].  ^In the "v2" interface,
                   4947: ** the more specific error code is returned directly by sqlite3_step().
                   4948: **
                   4949: ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
                   4950: ** Perhaps it was called on a [prepared statement] that has
                   4951: ** already been [sqlite3_finalize | finalized] or on one that had
                   4952: ** previously returned [SQLITE_ERROR] or [SQLITE_DONE].  Or it could
                   4953: ** be the case that the same database connection is being used by two or
                   4954: ** more threads at the same moment in time.
                   4955: **
                   4956: ** For all versions of SQLite up to and including 3.6.23.1, a call to
                   4957: ** [sqlite3_reset()] was required after sqlite3_step() returned anything
                   4958: ** other than [SQLITE_ROW] before any subsequent invocation of
1.5       misho    4959: ** sqlite3_step().  Failure to reset the prepared statement using
1.2       misho    4960: ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
1.5       misho    4961: ** sqlite3_step().  But after [version 3.6.23.1] ([dateof:3.6.23.1],
                   4962: ** sqlite3_step() began
1.2       misho    4963: ** calling [sqlite3_reset()] automatically in this circumstance rather
                   4964: ** than returning [SQLITE_MISUSE].  This is not considered a compatibility
                   4965: ** break because any application that ever receives an SQLITE_MISUSE error
                   4966: ** is broken by definition.  The [SQLITE_OMIT_AUTORESET] compile-time option
                   4967: ** can be used to restore the legacy behavior.
                   4968: **
                   4969: ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
                   4970: ** API always returns a generic error code, [SQLITE_ERROR], following any
                   4971: ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE].  You must call
                   4972: ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
                   4973: ** specific [error codes] that better describes the error.
                   4974: ** We admit that this is a goofy design.  The problem has been fixed
                   4975: ** with the "v2" interface.  If you prepare all of your SQL statements
1.5       misho    4976: ** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()]
                   4977: ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead
1.2       misho    4978: ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
                   4979: ** then the more specific [error codes] are returned directly
1.5       misho    4980: ** by sqlite3_step().  The use of the "vX" interfaces is recommended.
1.2       misho    4981: */
                   4982: SQLITE_API int sqlite3_step(sqlite3_stmt*);
                   4983: 
                   4984: /*
                   4985: ** CAPI3REF: Number of columns in a result set
1.4       misho    4986: ** METHOD: sqlite3_stmt
1.2       misho    4987: **
                   4988: ** ^The sqlite3_data_count(P) interface returns the number of columns in the
                   4989: ** current row of the result set of [prepared statement] P.
                   4990: ** ^If prepared statement P does not have results ready to return
1.5       misho    4991: ** (via calls to the [sqlite3_column_int | sqlite3_column()] family of
1.2       misho    4992: ** interfaces) then sqlite3_data_count(P) returns 0.
                   4993: ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
                   4994: ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
                   4995: ** [sqlite3_step](P) returned [SQLITE_DONE].  ^The sqlite3_data_count(P)
                   4996: ** will return non-zero if previous call to [sqlite3_step](P) returned
                   4997: ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
                   4998: ** where it always returns zero since each step of that multi-step
                   4999: ** pragma returns 0 columns of data.
                   5000: **
                   5001: ** See also: [sqlite3_column_count()]
                   5002: */
                   5003: SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
                   5004: 
                   5005: /*
                   5006: ** CAPI3REF: Fundamental Datatypes
                   5007: ** KEYWORDS: SQLITE_TEXT
                   5008: **
                   5009: ** ^(Every value in SQLite has one of five fundamental datatypes:
                   5010: **
                   5011: ** <ul>
                   5012: ** <li> 64-bit signed integer
                   5013: ** <li> 64-bit IEEE floating point number
                   5014: ** <li> string
                   5015: ** <li> BLOB
                   5016: ** <li> NULL
                   5017: ** </ul>)^
                   5018: **
                   5019: ** These constants are codes for each of those types.
                   5020: **
                   5021: ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
                   5022: ** for a completely different meaning.  Software that links against both
                   5023: ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
                   5024: ** SQLITE_TEXT.
                   5025: */
                   5026: #define SQLITE_INTEGER  1
                   5027: #define SQLITE_FLOAT    2
                   5028: #define SQLITE_BLOB     4
                   5029: #define SQLITE_NULL     5
                   5030: #ifdef SQLITE_TEXT
                   5031: # undef SQLITE_TEXT
                   5032: #else
                   5033: # define SQLITE_TEXT     3
                   5034: #endif
                   5035: #define SQLITE3_TEXT     3
                   5036: 
                   5037: /*
                   5038: ** CAPI3REF: Result Values From A Query
                   5039: ** KEYWORDS: {column access functions}
1.4       misho    5040: ** METHOD: sqlite3_stmt
1.2       misho    5041: **
1.5       misho    5042: ** <b>Summary:</b>
                   5043: ** <blockquote><table border=0 cellpadding=0 cellspacing=0>
                   5044: ** <tr><td><b>sqlite3_column_blob</b><td>&rarr;<td>BLOB result
                   5045: ** <tr><td><b>sqlite3_column_double</b><td>&rarr;<td>REAL result
                   5046: ** <tr><td><b>sqlite3_column_int</b><td>&rarr;<td>32-bit INTEGER result
                   5047: ** <tr><td><b>sqlite3_column_int64</b><td>&rarr;<td>64-bit INTEGER result
                   5048: ** <tr><td><b>sqlite3_column_text</b><td>&rarr;<td>UTF-8 TEXT result
                   5049: ** <tr><td><b>sqlite3_column_text16</b><td>&rarr;<td>UTF-16 TEXT result
                   5050: ** <tr><td><b>sqlite3_column_value</b><td>&rarr;<td>The result as an
                   5051: ** [sqlite3_value|unprotected sqlite3_value] object.
                   5052: ** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
                   5053: ** <tr><td><b>sqlite3_column_bytes</b><td>&rarr;<td>Size of a BLOB
                   5054: ** or a UTF-8 TEXT result in bytes
                   5055: ** <tr><td><b>sqlite3_column_bytes16&nbsp;&nbsp;</b>
                   5056: ** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
                   5057: ** TEXT in bytes
                   5058: ** <tr><td><b>sqlite3_column_type</b><td>&rarr;<td>Default
                   5059: ** datatype of the result
                   5060: ** </table></blockquote>
                   5061: **
                   5062: ** <b>Details:</b>
                   5063: **
1.2       misho    5064: ** ^These routines return information about a single column of the current
                   5065: ** result row of a query.  ^In every case the first argument is a pointer
                   5066: ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
                   5067: ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
                   5068: ** and the second argument is the index of the column for which information
                   5069: ** should be returned. ^The leftmost column of the result set has the index 0.
                   5070: ** ^The number of columns in the result can be determined using
                   5071: ** [sqlite3_column_count()].
                   5072: **
                   5073: ** If the SQL statement does not currently point to a valid row, or if the
                   5074: ** column index is out of range, the result is undefined.
                   5075: ** These routines may only be called when the most recent call to
                   5076: ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
                   5077: ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
                   5078: ** If any of these routines are called after [sqlite3_reset()] or
                   5079: ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
                   5080: ** something other than [SQLITE_ROW], the results are undefined.
                   5081: ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
                   5082: ** are called from a different thread while any of these routines
                   5083: ** are pending, then the results are undefined.
                   5084: **
1.5       misho    5085: ** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16)
                   5086: ** each return the value of a result column in a specific data format.  If
                   5087: ** the result column is not initially in the requested format (for example,
                   5088: ** if the query returns an integer but the sqlite3_column_text() interface
                   5089: ** is used to extract the value) then an automatic type conversion is performed.
                   5090: **
1.2       misho    5091: ** ^The sqlite3_column_type() routine returns the
                   5092: ** [SQLITE_INTEGER | datatype code] for the initial data type
                   5093: ** of the result column.  ^The returned value is one of [SQLITE_INTEGER],
1.5       misho    5094: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].
                   5095: ** The return value of sqlite3_column_type() can be used to decide which
                   5096: ** of the first six interface should be used to extract the column value.
                   5097: ** The value returned by sqlite3_column_type() is only meaningful if no
                   5098: ** automatic type conversions have occurred for the value in question.
                   5099: ** After a type conversion, the result of calling sqlite3_column_type()
                   5100: ** is undefined, though harmless.  Future
1.2       misho    5101: ** versions of SQLite may change the behavior of sqlite3_column_type()
                   5102: ** following a type conversion.
                   5103: **
1.5       misho    5104: ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes()
                   5105: ** or sqlite3_column_bytes16() interfaces can be used to determine the size
                   5106: ** of that BLOB or string.
                   5107: **
1.2       misho    5108: ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
                   5109: ** routine returns the number of bytes in that BLOB or string.
                   5110: ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
                   5111: ** the string to UTF-8 and then returns the number of bytes.
                   5112: ** ^If the result is a numeric value then sqlite3_column_bytes() uses
                   5113: ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
                   5114: ** the number of bytes in that string.
                   5115: ** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
                   5116: **
                   5117: ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
                   5118: ** routine returns the number of bytes in that BLOB or string.
                   5119: ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
                   5120: ** the string to UTF-16 and then returns the number of bytes.
                   5121: ** ^If the result is a numeric value then sqlite3_column_bytes16() uses
                   5122: ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
                   5123: ** the number of bytes in that string.
                   5124: ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
                   5125: **
1.5       misho    5126: ** ^The values returned by [sqlite3_column_bytes()] and
1.2       misho    5127: ** [sqlite3_column_bytes16()] do not include the zero terminators at the end
                   5128: ** of the string.  ^For clarity: the values returned by
                   5129: ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
                   5130: ** bytes in the string, not the number of characters.
                   5131: **
                   5132: ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
                   5133: ** even empty strings, are always zero-terminated.  ^The return
                   5134: ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
                   5135: **
1.6.2.1 ! misho    5136: ** ^Strings returned by sqlite3_column_text16() always have the endianness
        !          5137: ** which is native to the platform, regardless of the text encoding set
        !          5138: ** for the database.
        !          5139: **
1.4       misho    5140: ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an
                   5141: ** [unprotected sqlite3_value] object.  In a multithreaded environment,
                   5142: ** an unprotected sqlite3_value object may only be used safely with
                   5143: ** [sqlite3_bind_value()] and [sqlite3_result_value()].
1.2       misho    5144: ** If the [unprotected sqlite3_value] object returned by
                   5145: ** [sqlite3_column_value()] is used in any other way, including calls
                   5146: ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
1.4       misho    5147: ** or [sqlite3_value_bytes()], the behavior is not threadsafe.
1.5       misho    5148: ** Hence, the sqlite3_column_value() interface
                   5149: ** is normally only useful within the implementation of
                   5150: ** [application-defined SQL functions] or [virtual tables], not within
                   5151: ** top-level application code.
1.2       misho    5152: **
1.6.2.1 ! misho    5153: ** These routines may attempt to convert the datatype of the result.
1.5       misho    5154: ** ^For example, if the internal representation is FLOAT and a text result
1.2       misho    5155: ** is requested, [sqlite3_snprintf()] is used internally to perform the
                   5156: ** conversion automatically.  ^(The following table details the conversions
                   5157: ** that are applied:
                   5158: **
                   5159: ** <blockquote>
                   5160: ** <table border="1">
                   5161: ** <tr><th> Internal<br>Type <th> Requested<br>Type <th>  Conversion
                   5162: **
                   5163: ** <tr><td>  NULL    <td> INTEGER   <td> Result is 0
                   5164: ** <tr><td>  NULL    <td>  FLOAT    <td> Result is 0.0
1.4       misho    5165: ** <tr><td>  NULL    <td>   TEXT    <td> Result is a NULL pointer
                   5166: ** <tr><td>  NULL    <td>   BLOB    <td> Result is a NULL pointer
1.2       misho    5167: ** <tr><td> INTEGER  <td>  FLOAT    <td> Convert from integer to float
                   5168: ** <tr><td> INTEGER  <td>   TEXT    <td> ASCII rendering of the integer
                   5169: ** <tr><td> INTEGER  <td>   BLOB    <td> Same as INTEGER->TEXT
1.4       misho    5170: ** <tr><td>  FLOAT   <td> INTEGER   <td> [CAST] to INTEGER
1.2       misho    5171: ** <tr><td>  FLOAT   <td>   TEXT    <td> ASCII rendering of the float
1.4       misho    5172: ** <tr><td>  FLOAT   <td>   BLOB    <td> [CAST] to BLOB
                   5173: ** <tr><td>  TEXT    <td> INTEGER   <td> [CAST] to INTEGER
                   5174: ** <tr><td>  TEXT    <td>  FLOAT    <td> [CAST] to REAL
1.2       misho    5175: ** <tr><td>  TEXT    <td>   BLOB    <td> No change
1.4       misho    5176: ** <tr><td>  BLOB    <td> INTEGER   <td> [CAST] to INTEGER
                   5177: ** <tr><td>  BLOB    <td>  FLOAT    <td> [CAST] to REAL
1.6.2.1 ! misho    5178: ** <tr><td>  BLOB    <td>   TEXT    <td> [CAST] to TEXT, ensure zero terminator
1.2       misho    5179: ** </table>
                   5180: ** </blockquote>)^
                   5181: **
                   5182: ** Note that when type conversions occur, pointers returned by prior
                   5183: ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
                   5184: ** sqlite3_column_text16() may be invalidated.
                   5185: ** Type conversions and pointer invalidations might occur
                   5186: ** in the following cases:
                   5187: **
                   5188: ** <ul>
                   5189: ** <li> The initial content is a BLOB and sqlite3_column_text() or
                   5190: **      sqlite3_column_text16() is called.  A zero-terminator might
                   5191: **      need to be added to the string.</li>
                   5192: ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
                   5193: **      sqlite3_column_text16() is called.  The content must be converted
                   5194: **      to UTF-16.</li>
                   5195: ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
                   5196: **      sqlite3_column_text() is called.  The content must be converted
                   5197: **      to UTF-8.</li>
                   5198: ** </ul>
                   5199: **
                   5200: ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
                   5201: ** not invalidate a prior pointer, though of course the content of the buffer
                   5202: ** that the prior pointer references will have been modified.  Other kinds
                   5203: ** of conversion are done in place when it is possible, but sometimes they
                   5204: ** are not possible and in those cases prior pointers are invalidated.
                   5205: **
1.4       misho    5206: ** The safest policy is to invoke these routines
1.2       misho    5207: ** in one of the following ways:
                   5208: **
                   5209: ** <ul>
                   5210: **  <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
                   5211: **  <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
                   5212: **  <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
                   5213: ** </ul>
                   5214: **
                   5215: ** In other words, you should call sqlite3_column_text(),
                   5216: ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
                   5217: ** into the desired format, then invoke sqlite3_column_bytes() or
                   5218: ** sqlite3_column_bytes16() to find the size of the result.  Do not mix calls
                   5219: ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
                   5220: ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
                   5221: ** with calls to sqlite3_column_bytes().
                   5222: **
                   5223: ** ^The pointers returned are valid until a type conversion occurs as
                   5224: ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
                   5225: ** [sqlite3_finalize()] is called.  ^The memory space used to hold strings
1.5       misho    5226: ** and BLOBs is freed automatically.  Do not pass the pointers returned
1.4       misho    5227: ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
1.2       misho    5228: ** [sqlite3_free()].
                   5229: **
1.5       misho    5230: ** As long as the input parameters are correct, these routines will only
                   5231: ** fail if an out-of-memory error occurs during a format conversion.
                   5232: ** Only the following subset of interfaces are subject to out-of-memory
                   5233: ** errors:
                   5234: **
                   5235: ** <ul>
                   5236: ** <li> sqlite3_column_blob()
                   5237: ** <li> sqlite3_column_text()
                   5238: ** <li> sqlite3_column_text16()
                   5239: ** <li> sqlite3_column_bytes()
                   5240: ** <li> sqlite3_column_bytes16()
                   5241: ** </ul>
                   5242: **
                   5243: ** If an out-of-memory error occurs, then the return value from these
                   5244: ** routines is the same as if the column had contained an SQL NULL value.
                   5245: ** Valid SQL NULL returns can be distinguished from out-of-memory errors
                   5246: ** by invoking the [sqlite3_errcode()] immediately after the suspect
                   5247: ** return value is obtained and before any
                   5248: ** other SQLite interface is called on the same [database connection].
1.2       misho    5249: */
                   5250: SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
                   5251: SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
                   5252: SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
                   5253: SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
                   5254: SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
                   5255: SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
1.5       misho    5256: SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
                   5257: SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
                   5258: SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
1.2       misho    5259: SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
                   5260: 
                   5261: /*
                   5262: ** CAPI3REF: Destroy A Prepared Statement Object
1.4       misho    5263: ** DESTRUCTOR: sqlite3_stmt
1.2       misho    5264: **
                   5265: ** ^The sqlite3_finalize() function is called to delete a [prepared statement].
                   5266: ** ^If the most recent evaluation of the statement encountered no errors
                   5267: ** or if the statement is never been evaluated, then sqlite3_finalize() returns
                   5268: ** SQLITE_OK.  ^If the most recent evaluation of statement S failed, then
                   5269: ** sqlite3_finalize(S) returns the appropriate [error code] or
                   5270: ** [extended error code].
                   5271: **
                   5272: ** ^The sqlite3_finalize(S) routine can be called at any point during
                   5273: ** the life cycle of [prepared statement] S:
                   5274: ** before statement S is ever evaluated, after
                   5275: ** one or more calls to [sqlite3_reset()], or after any call
                   5276: ** to [sqlite3_step()] regardless of whether or not the statement has
                   5277: ** completed execution.
                   5278: **
                   5279: ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
                   5280: **
                   5281: ** The application must finalize every [prepared statement] in order to avoid
                   5282: ** resource leaks.  It is a grievous error for the application to try to use
                   5283: ** a prepared statement after it has been finalized.  Any use of a prepared
                   5284: ** statement after it has been finalized can result in undefined and
                   5285: ** undesirable behavior such as segfaults and heap corruption.
                   5286: */
                   5287: SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
                   5288: 
                   5289: /*
                   5290: ** CAPI3REF: Reset A Prepared Statement Object
1.4       misho    5291: ** METHOD: sqlite3_stmt
1.2       misho    5292: **
                   5293: ** The sqlite3_reset() function is called to reset a [prepared statement]
                   5294: ** object back to its initial state, ready to be re-executed.
                   5295: ** ^Any SQL statement variables that had values bound to them using
                   5296: ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
                   5297: ** Use [sqlite3_clear_bindings()] to reset the bindings.
                   5298: **
                   5299: ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
                   5300: ** back to the beginning of its program.
                   5301: **
1.6.2.1 ! misho    5302: ** ^The return code from [sqlite3_reset(S)] indicates whether or not
        !          5303: ** the previous evaluation of prepared statement S completed successfully.
        !          5304: ** ^If [sqlite3_step(S)] has never before been called on S or if
        !          5305: ** [sqlite3_step(S)] has not been called since the previous call
        !          5306: ** to [sqlite3_reset(S)], then [sqlite3_reset(S)] will return
        !          5307: ** [SQLITE_OK].
1.2       misho    5308: **
                   5309: ** ^If the most recent call to [sqlite3_step(S)] for the
                   5310: ** [prepared statement] S indicated an error, then
                   5311: ** [sqlite3_reset(S)] returns an appropriate [error code].
1.6.2.1 ! misho    5312: ** ^The [sqlite3_reset(S)] interface might also return an [error code]
        !          5313: ** if there were no prior errors but the process of resetting
        !          5314: ** the prepared statement caused a new error. ^For example, if an
        !          5315: ** [INSERT] statement with a [RETURNING] clause is only stepped one time,
        !          5316: ** that one call to [sqlite3_step(S)] might return SQLITE_ROW but
        !          5317: ** the overall statement might still fail and the [sqlite3_reset(S)] call
        !          5318: ** might return SQLITE_BUSY if locking constraints prevent the
        !          5319: ** database change from committing.  Therefore, it is important that
        !          5320: ** applications check the return code from [sqlite3_reset(S)] even if
        !          5321: ** no prior call to [sqlite3_step(S)] indicated a problem.
1.2       misho    5322: **
                   5323: ** ^The [sqlite3_reset(S)] interface does not change the values
                   5324: ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
                   5325: */
                   5326: SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
                   5327: 
                   5328: /*
                   5329: ** CAPI3REF: Create Or Redefine SQL Functions
                   5330: ** KEYWORDS: {function creation routines}
1.4       misho    5331: ** METHOD: sqlite3
1.2       misho    5332: **
                   5333: ** ^These functions (collectively known as "function creation routines")
                   5334: ** are used to add SQL functions or aggregates or to redefine the behavior
1.5       misho    5335: ** of existing SQL functions or aggregates. The only differences between
                   5336: ** the three "sqlite3_create_function*" routines are the text encoding
                   5337: ** expected for the second parameter (the name of the function being
                   5338: ** created) and the presence or absence of a destructor callback for
                   5339: ** the application data pointer. Function sqlite3_create_window_function()
                   5340: ** is similar, but allows the user to supply the extra callback functions
                   5341: ** needed by [aggregate window functions].
1.2       misho    5342: **
                   5343: ** ^The first parameter is the [database connection] to which the SQL
                   5344: ** function is to be added.  ^If an application uses more than one database
                   5345: ** connection then application-defined SQL functions must be added
                   5346: ** to each database connection separately.
                   5347: **
                   5348: ** ^The second parameter is the name of the SQL function to be created or
                   5349: ** redefined.  ^The length of the name is limited to 255 bytes in a UTF-8
                   5350: ** representation, exclusive of the zero-terminator.  ^Note that the name
1.5       misho    5351: ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
1.2       misho    5352: ** ^Any attempt to create a function with a longer name
                   5353: ** will result in [SQLITE_MISUSE] being returned.
                   5354: **
                   5355: ** ^The third parameter (nArg)
                   5356: ** is the number of arguments that the SQL function or
                   5357: ** aggregate takes. ^If this parameter is -1, then the SQL function or
                   5358: ** aggregate may take any number of arguments between 0 and the limit
                   5359: ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]).  If the third
                   5360: ** parameter is less than -1 or greater than 127 then the behavior is
                   5361: ** undefined.
                   5362: **
                   5363: ** ^The fourth parameter, eTextRep, specifies what
                   5364: ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
1.4       misho    5365: ** its parameters.  The application should set this parameter to
1.5       misho    5366: ** [SQLITE_UTF16LE] if the function implementation invokes
1.4       misho    5367: ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the
                   5368: ** implementation invokes [sqlite3_value_text16be()] on an input, or
                   5369: ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]
                   5370: ** otherwise.  ^The same SQL function may be registered multiple times using
                   5371: ** different preferred text encodings, with different implementations for
                   5372: ** each encoding.
1.2       misho    5373: ** ^When multiple implementations of the same function are available, SQLite
                   5374: ** will pick the one that involves the least amount of data conversion.
1.4       misho    5375: **
                   5376: ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]
                   5377: ** to signal that the function will always return the same result given
                   5378: ** the same inputs within a single SQL statement.  Most SQL functions are
                   5379: ** deterministic.  The built-in [random()] SQL function is an example of a
                   5380: ** function that is not deterministic.  The SQLite query planner is able to
                   5381: ** perform additional optimizations on deterministic functions, so use
                   5382: ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.
1.2       misho    5383: **
1.5       misho    5384: ** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY]
                   5385: ** flag, which if present prevents the function from being invoked from
                   5386: ** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions,
                   5387: ** index expressions, or the WHERE clause of partial indexes.
                   5388: **
                   5389: ** For best security, the [SQLITE_DIRECTONLY] flag is recommended for
                   5390: ** all application-defined SQL functions that do not need to be
                   5391: ** used inside of triggers, view, CHECK constraints, or other elements of
                   5392: ** the database schema.  This flags is especially recommended for SQL
                   5393: ** functions that have side effects or reveal internal application state.
                   5394: ** Without this flag, an attacker might be able to modify the schema of
                   5395: ** a database file to include invocations of the function with parameters
                   5396: ** chosen by the attacker, which the application will then execute when
                   5397: ** the database file is opened and read.
                   5398: **
1.2       misho    5399: ** ^(The fifth parameter is an arbitrary pointer.  The implementation of the
                   5400: ** function can gain access to this pointer using [sqlite3_user_data()].)^
                   5401: **
1.5       misho    5402: ** ^The sixth, seventh and eighth parameters passed to the three
                   5403: ** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are
1.2       misho    5404: ** pointers to C-language functions that implement the SQL function or
                   5405: ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
                   5406: ** callback only; NULL pointers must be passed as the xStep and xFinal
                   5407: ** parameters. ^An aggregate SQL function requires an implementation of xStep
                   5408: ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
                   5409: ** SQL function or aggregate, pass NULL pointers for all three function
                   5410: ** callbacks.
                   5411: **
1.5       misho    5412: ** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue
                   5413: ** and xInverse) passed to sqlite3_create_window_function are pointers to
                   5414: ** C-language callbacks that implement the new function. xStep and xFinal
                   5415: ** must both be non-NULL. xValue and xInverse may either both be NULL, in
                   5416: ** which case a regular aggregate function is created, or must both be
                   5417: ** non-NULL, in which case the new function may be used as either an aggregate
                   5418: ** or aggregate window function. More details regarding the implementation
                   5419: ** of aggregate window functions are
                   5420: ** [user-defined window functions|available here].
                   5421: **
                   5422: ** ^(If the final parameter to sqlite3_create_function_v2() or
                   5423: ** sqlite3_create_window_function() is not NULL, then it is destructor for
                   5424: ** the application data pointer. The destructor is invoked when the function
                   5425: ** is deleted, either by being overloaded or when the database connection
                   5426: ** closes.)^ ^The destructor is also invoked if the call to
                   5427: ** sqlite3_create_function_v2() fails.  ^When the destructor callback is
                   5428: ** invoked, it is passed a single argument which is a copy of the application
                   5429: ** data pointer which was the fifth parameter to sqlite3_create_function_v2().
1.2       misho    5430: **
                   5431: ** ^It is permitted to register multiple implementations of the same
                   5432: ** functions with the same name but with either differing numbers of
                   5433: ** arguments or differing preferred text encodings.  ^SQLite will use
                   5434: ** the implementation that most closely matches the way in which the
                   5435: ** SQL function is used.  ^A function implementation with a non-negative
                   5436: ** nArg parameter is a better match than a function implementation with
                   5437: ** a negative nArg.  ^A function where the preferred text encoding
                   5438: ** matches the database encoding is a better
1.5       misho    5439: ** match than a function where the encoding is different.
1.2       misho    5440: ** ^A function where the encoding difference is between UTF16le and UTF16be
                   5441: ** is a closer match than a function where the encoding difference is
                   5442: ** between UTF8 and UTF16.
                   5443: **
                   5444: ** ^Built-in functions may be overloaded by new application-defined functions.
                   5445: **
                   5446: ** ^An application-defined function is permitted to call other
                   5447: ** SQLite interfaces.  However, such calls must not
                   5448: ** close the database connection nor finalize or reset the prepared
                   5449: ** statement in which the function is running.
                   5450: */
                   5451: SQLITE_API int sqlite3_create_function(
                   5452:   sqlite3 *db,
                   5453:   const char *zFunctionName,
                   5454:   int nArg,
                   5455:   int eTextRep,
                   5456:   void *pApp,
                   5457:   void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
                   5458:   void (*xStep)(sqlite3_context*,int,sqlite3_value**),
                   5459:   void (*xFinal)(sqlite3_context*)
                   5460: );
                   5461: SQLITE_API int sqlite3_create_function16(
                   5462:   sqlite3 *db,
                   5463:   const void *zFunctionName,
                   5464:   int nArg,
                   5465:   int eTextRep,
                   5466:   void *pApp,
                   5467:   void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
                   5468:   void (*xStep)(sqlite3_context*,int,sqlite3_value**),
                   5469:   void (*xFinal)(sqlite3_context*)
                   5470: );
                   5471: SQLITE_API int sqlite3_create_function_v2(
                   5472:   sqlite3 *db,
                   5473:   const char *zFunctionName,
                   5474:   int nArg,
                   5475:   int eTextRep,
                   5476:   void *pApp,
                   5477:   void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
                   5478:   void (*xStep)(sqlite3_context*,int,sqlite3_value**),
                   5479:   void (*xFinal)(sqlite3_context*),
                   5480:   void(*xDestroy)(void*)
                   5481: );
1.5       misho    5482: SQLITE_API int sqlite3_create_window_function(
                   5483:   sqlite3 *db,
                   5484:   const char *zFunctionName,
                   5485:   int nArg,
                   5486:   int eTextRep,
                   5487:   void *pApp,
                   5488:   void (*xStep)(sqlite3_context*,int,sqlite3_value**),
                   5489:   void (*xFinal)(sqlite3_context*),
                   5490:   void (*xValue)(sqlite3_context*),
                   5491:   void (*xInverse)(sqlite3_context*,int,sqlite3_value**),
                   5492:   void(*xDestroy)(void*)
                   5493: );
1.2       misho    5494: 
                   5495: /*
                   5496: ** CAPI3REF: Text Encodings
                   5497: **
                   5498: ** These constant define integer codes that represent the various
                   5499: ** text encodings supported by SQLite.
                   5500: */
1.4       misho    5501: #define SQLITE_UTF8           1    /* IMP: R-37514-35566 */
                   5502: #define SQLITE_UTF16LE        2    /* IMP: R-03371-37637 */
                   5503: #define SQLITE_UTF16BE        3    /* IMP: R-51971-34154 */
1.2       misho    5504: #define SQLITE_UTF16          4    /* Use native byte order */
1.4       misho    5505: #define SQLITE_ANY            5    /* Deprecated */
1.2       misho    5506: #define SQLITE_UTF16_ALIGNED  8    /* sqlite3_create_collation only */
                   5507: 
                   5508: /*
1.4       misho    5509: ** CAPI3REF: Function Flags
                   5510: **
1.5       misho    5511: ** These constants may be ORed together with the
1.4       misho    5512: ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument
                   5513: ** to [sqlite3_create_function()], [sqlite3_create_function16()], or
                   5514: ** [sqlite3_create_function_v2()].
1.5       misho    5515: **
                   5516: ** <dl>
                   5517: ** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd>
                   5518: ** The SQLITE_DETERMINISTIC flag means that the new function always gives
                   5519: ** the same output when the input parameters are the same.
                   5520: ** The [abs|abs() function] is deterministic, for example, but
                   5521: ** [randomblob|randomblob()] is not.  Functions must
                   5522: ** be deterministic in order to be used in certain contexts such as
                   5523: ** with the WHERE clause of [partial indexes] or in [generated columns].
                   5524: ** SQLite might also optimize deterministic functions by factoring them
                   5525: ** out of inner loops.
                   5526: ** </dd>
                   5527: **
                   5528: ** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd>
                   5529: ** The SQLITE_DIRECTONLY flag means that the function may only be invoked
                   5530: ** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in
                   5531: ** schema structures such as [CHECK constraints], [DEFAULT clauses],
                   5532: ** [expression indexes], [partial indexes], or [generated columns].
1.6.2.1 ! misho    5533: ** <p>
        !          5534: ** The SQLITE_DIRECTONLY flag is recommended for any
        !          5535: ** [application-defined SQL function]
        !          5536: ** that has side-effects or that could potentially leak sensitive information.
        !          5537: ** This will prevent attacks in which an application is tricked
        !          5538: ** into using a database file that has had its schema surreptitiously
        !          5539: ** modified to invoke the application-defined function in ways that are
        !          5540: ** harmful.
        !          5541: ** <p>
        !          5542: ** Some people say it is good practice to set SQLITE_DIRECTONLY on all
        !          5543: ** [application-defined SQL functions], regardless of whether or not they
        !          5544: ** are security sensitive, as doing so prevents those functions from being used
        !          5545: ** inside of the database schema, and thus ensures that the database
        !          5546: ** can be inspected and modified using generic tools (such as the [CLI])
        !          5547: ** that do not have access to the application-defined functions.
1.5       misho    5548: ** </dd>
                   5549: **
                   5550: ** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd>
                   5551: ** The SQLITE_INNOCUOUS flag means that the function is unlikely
                   5552: ** to cause problems even if misused.  An innocuous function should have
                   5553: ** no side effects and should not depend on any values other than its
                   5554: ** input parameters. The [abs|abs() function] is an example of an
                   5555: ** innocuous function.
                   5556: ** The [load_extension() SQL function] is not innocuous because of its
                   5557: ** side effects.
                   5558: ** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not
                   5559: ** exactly the same.  The [random|random() function] is an example of a
                   5560: ** function that is innocuous but not deterministic.
                   5561: ** <p>Some heightened security settings
                   5562: ** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF])
                   5563: ** disable the use of SQL functions inside views and triggers and in
                   5564: ** schema structures such as [CHECK constraints], [DEFAULT clauses],
                   5565: ** [expression indexes], [partial indexes], and [generated columns] unless
                   5566: ** the function is tagged with SQLITE_INNOCUOUS.  Most built-in functions
                   5567: ** are innocuous.  Developers are advised to avoid using the
                   5568: ** SQLITE_INNOCUOUS flag for application-defined functions unless the
                   5569: ** function has been carefully audited and found to be free of potentially
                   5570: ** security-adverse side-effects and information-leaks.
                   5571: ** </dd>
                   5572: **
                   5573: ** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd>
                   5574: ** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call
                   5575: ** [sqlite3_value_subtype()] to inspect the sub-types of its arguments.
                   5576: ** Specifying this flag makes no difference for scalar or aggregate user
                   5577: ** functions. However, if it is not specified for a user-defined window
                   5578: ** function, then any sub-types belonging to arguments passed to the window
                   5579: ** function may be discarded before the window function is called (i.e.
                   5580: ** sqlite3_value_subtype() will always return 0).
                   5581: ** </dd>
                   5582: ** </dl>
1.4       misho    5583: */
1.5       misho    5584: #define SQLITE_DETERMINISTIC    0x000000800
                   5585: #define SQLITE_DIRECTONLY       0x000080000
                   5586: #define SQLITE_SUBTYPE          0x000100000
                   5587: #define SQLITE_INNOCUOUS        0x000200000
1.4       misho    5588: 
                   5589: /*
1.2       misho    5590: ** CAPI3REF: Deprecated Functions
                   5591: ** DEPRECATED
                   5592: **
                   5593: ** These functions are [deprecated].  In order to maintain
1.5       misho    5594: ** backwards compatibility with older code, these functions continue
1.2       misho    5595: ** to be supported.  However, new applications should avoid
1.4       misho    5596: ** the use of these functions.  To encourage programmers to avoid
                   5597: ** these functions, we will not explain what they do.
1.2       misho    5598: */
                   5599: #ifndef SQLITE_OMIT_DEPRECATED
                   5600: SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
                   5601: SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
                   5602: SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
                   5603: SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
                   5604: SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
1.4       misho    5605: SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
                   5606:                       void*,sqlite3_int64);
1.2       misho    5607: #endif
                   5608: 
                   5609: /*
1.4       misho    5610: ** CAPI3REF: Obtaining SQL Values
                   5611: ** METHOD: sqlite3_value
1.2       misho    5612: **
1.5       misho    5613: ** <b>Summary:</b>
                   5614: ** <blockquote><table border=0 cellpadding=0 cellspacing=0>
                   5615: ** <tr><td><b>sqlite3_value_blob</b><td>&rarr;<td>BLOB value
                   5616: ** <tr><td><b>sqlite3_value_double</b><td>&rarr;<td>REAL value
                   5617: ** <tr><td><b>sqlite3_value_int</b><td>&rarr;<td>32-bit INTEGER value
                   5618: ** <tr><td><b>sqlite3_value_int64</b><td>&rarr;<td>64-bit INTEGER value
                   5619: ** <tr><td><b>sqlite3_value_pointer</b><td>&rarr;<td>Pointer value
                   5620: ** <tr><td><b>sqlite3_value_text</b><td>&rarr;<td>UTF-8 TEXT value
                   5621: ** <tr><td><b>sqlite3_value_text16</b><td>&rarr;<td>UTF-16 TEXT value in
                   5622: ** the native byteorder
                   5623: ** <tr><td><b>sqlite3_value_text16be</b><td>&rarr;<td>UTF-16be TEXT value
                   5624: ** <tr><td><b>sqlite3_value_text16le</b><td>&rarr;<td>UTF-16le TEXT value
                   5625: ** <tr><td>&nbsp;<td>&nbsp;<td>&nbsp;
                   5626: ** <tr><td><b>sqlite3_value_bytes</b><td>&rarr;<td>Size of a BLOB
                   5627: ** or a UTF-8 TEXT in bytes
                   5628: ** <tr><td><b>sqlite3_value_bytes16&nbsp;&nbsp;</b>
                   5629: ** <td>&rarr;&nbsp;&nbsp;<td>Size of UTF-16
                   5630: ** TEXT in bytes
                   5631: ** <tr><td><b>sqlite3_value_type</b><td>&rarr;<td>Default
                   5632: ** datatype of the value
                   5633: ** <tr><td><b>sqlite3_value_numeric_type&nbsp;&nbsp;</b>
                   5634: ** <td>&rarr;&nbsp;&nbsp;<td>Best numeric datatype of the value
                   5635: ** <tr><td><b>sqlite3_value_nochange&nbsp;&nbsp;</b>
                   5636: ** <td>&rarr;&nbsp;&nbsp;<td>True if the column is unchanged in an UPDATE
                   5637: ** against a virtual table.
                   5638: ** <tr><td><b>sqlite3_value_frombind&nbsp;&nbsp;</b>
                   5639: ** <td>&rarr;&nbsp;&nbsp;<td>True if value originated from a [bound parameter]
                   5640: ** </table></blockquote>
                   5641: **
                   5642: ** <b>Details:</b>
                   5643: **
                   5644: ** These routines extract type, size, and content information from
                   5645: ** [protected sqlite3_value] objects.  Protected sqlite3_value objects
                   5646: ** are used to pass parameter information into the functions that
                   5647: ** implement [application-defined SQL functions] and [virtual tables].
1.2       misho    5648: **
                   5649: ** These routines work only with [protected sqlite3_value] objects.
                   5650: ** Any attempt to use these routines on an [unprotected sqlite3_value]
1.5       misho    5651: ** is not threadsafe.
1.2       misho    5652: **
                   5653: ** ^These routines work just like the corresponding [column access functions]
1.4       misho    5654: ** except that these routines take a single [protected sqlite3_value] object
1.2       misho    5655: ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
                   5656: **
                   5657: ** ^The sqlite3_value_text16() interface extracts a UTF-16 string
                   5658: ** in the native byte-order of the host machine.  ^The
                   5659: ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
                   5660: ** extract UTF-16 strings as big-endian and little-endian respectively.
                   5661: **
1.5       misho    5662: ** ^If [sqlite3_value] object V was initialized
                   5663: ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)]
                   5664: ** and if X and Y are strings that compare equal according to strcmp(X,Y),
                   5665: ** then sqlite3_value_pointer(V,Y) will return the pointer P.  ^Otherwise,
                   5666: ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer()
                   5667: ** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
                   5668: **
                   5669: ** ^(The sqlite3_value_type(V) interface returns the
                   5670: ** [SQLITE_INTEGER | datatype code] for the initial datatype of the
                   5671: ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER],
                   5672: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^
                   5673: ** Other interfaces might change the datatype for an sqlite3_value object.
                   5674: ** For example, if the datatype is initially SQLITE_INTEGER and
                   5675: ** sqlite3_value_text(V) is called to extract a text value for that
                   5676: ** integer, then subsequent calls to sqlite3_value_type(V) might return
                   5677: ** SQLITE_TEXT.  Whether or not a persistent internal datatype conversion
                   5678: ** occurs is undefined and may change from one release of SQLite to the next.
                   5679: **
1.2       misho    5680: ** ^(The sqlite3_value_numeric_type() interface attempts to apply
                   5681: ** numeric affinity to the value.  This means that an attempt is
                   5682: ** made to convert the value to an integer or floating point.  If
                   5683: ** such a conversion is possible without loss of information (in other
                   5684: ** words, if the value is a string that looks like a number)
                   5685: ** then the conversion is performed.  Otherwise no conversion occurs.
                   5686: ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
                   5687: **
1.5       misho    5688: ** ^Within the [xUpdate] method of a [virtual table], the
                   5689: ** sqlite3_value_nochange(X) interface returns true if and only if
                   5690: ** the column corresponding to X is unchanged by the UPDATE operation
                   5691: ** that the xUpdate method call was invoked to implement and if
                   5692: ** and the prior [xColumn] method call that was invoked to extracted
                   5693: ** the value for that column returned without setting a result (probably
                   5694: ** because it queried [sqlite3_vtab_nochange()] and found that the column
                   5695: ** was unchanging).  ^Within an [xUpdate] method, any value for which
                   5696: ** sqlite3_value_nochange(X) is true will in all other respects appear
                   5697: ** to be a NULL value.  If sqlite3_value_nochange(X) is invoked anywhere other
                   5698: ** than within an [xUpdate] method call for an UPDATE statement, then
                   5699: ** the return value is arbitrary and meaningless.
                   5700: **
                   5701: ** ^The sqlite3_value_frombind(X) interface returns non-zero if the
                   5702: ** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()]
                   5703: ** interfaces.  ^If X comes from an SQL literal value, or a table column,
                   5704: ** or an expression, then sqlite3_value_frombind(X) returns zero.
                   5705: **
1.2       misho    5706: ** Please pay particular attention to the fact that the pointer returned
                   5707: ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
                   5708: ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
                   5709: ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
                   5710: ** or [sqlite3_value_text16()].
                   5711: **
                   5712: ** These routines must be called from the same thread as
                   5713: ** the SQL function that supplied the [sqlite3_value*] parameters.
1.5       misho    5714: **
                   5715: ** As long as the input parameter is correct, these routines can only
                   5716: ** fail if an out-of-memory error occurs during a format conversion.
                   5717: ** Only the following subset of interfaces are subject to out-of-memory
                   5718: ** errors:
                   5719: **
                   5720: ** <ul>
                   5721: ** <li> sqlite3_value_blob()
                   5722: ** <li> sqlite3_value_text()
                   5723: ** <li> sqlite3_value_text16()
                   5724: ** <li> sqlite3_value_text16le()
                   5725: ** <li> sqlite3_value_text16be()
                   5726: ** <li> sqlite3_value_bytes()
                   5727: ** <li> sqlite3_value_bytes16()
                   5728: ** </ul>
                   5729: **
                   5730: ** If an out-of-memory error occurs, then the return value from these
                   5731: ** routines is the same as if the column had contained an SQL NULL value.
                   5732: ** Valid SQL NULL returns can be distinguished from out-of-memory errors
                   5733: ** by invoking the [sqlite3_errcode()] immediately after the suspect
                   5734: ** return value is obtained and before any
                   5735: ** other SQLite interface is called on the same [database connection].
1.2       misho    5736: */
                   5737: SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
                   5738: SQLITE_API double sqlite3_value_double(sqlite3_value*);
                   5739: SQLITE_API int sqlite3_value_int(sqlite3_value*);
                   5740: SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
1.5       misho    5741: SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*);
1.2       misho    5742: SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
                   5743: SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
                   5744: SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
                   5745: SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
1.5       misho    5746: SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
                   5747: SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
1.2       misho    5748: SQLITE_API int sqlite3_value_type(sqlite3_value*);
                   5749: SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
1.5       misho    5750: SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
                   5751: SQLITE_API int sqlite3_value_frombind(sqlite3_value*);
1.2       misho    5752: 
                   5753: /*
1.6.2.1 ! misho    5754: ** CAPI3REF: Report the internal text encoding state of an sqlite3_value object
        !          5755: ** METHOD: sqlite3_value
        !          5756: **
        !          5757: ** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8],
        !          5758: ** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding
        !          5759: ** of the value X, assuming that X has type TEXT.)^  If sqlite3_value_type(X)
        !          5760: ** returns something other than SQLITE_TEXT, then the return value from
        !          5761: ** sqlite3_value_encoding(X) is meaningless.  ^Calls to
        !          5762: ** [sqlite3_value_text(X)], [sqlite3_value_text16(X)], [sqlite3_value_text16be(X)],
        !          5763: ** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or
        !          5764: ** [sqlite3_value_bytes16(X)] might change the encoding of the value X and
        !          5765: ** thus change the return from subsequent calls to sqlite3_value_encoding(X).
        !          5766: **
        !          5767: ** This routine is intended for used by applications that test and validate
        !          5768: ** the SQLite implementation.  This routine is inquiring about the opaque
        !          5769: ** internal state of an [sqlite3_value] object.  Ordinary applications should
        !          5770: ** not need to know what the internal state of an sqlite3_value object is and
        !          5771: ** hence should not need to use this interface.
        !          5772: */
        !          5773: SQLITE_API int sqlite3_value_encoding(sqlite3_value*);
        !          5774: 
        !          5775: /*
1.4       misho    5776: ** CAPI3REF: Finding The Subtype Of SQL Values
                   5777: ** METHOD: sqlite3_value
                   5778: **
                   5779: ** The sqlite3_value_subtype(V) function returns the subtype for
                   5780: ** an [application-defined SQL function] argument V.  The subtype
                   5781: ** information can be used to pass a limited amount of context from
                   5782: ** one SQL function to another.  Use the [sqlite3_result_subtype()]
                   5783: ** routine to set the subtype for the return value of an SQL function.
                   5784: */
                   5785: SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*);
                   5786: 
                   5787: /*
                   5788: ** CAPI3REF: Copy And Free SQL Values
                   5789: ** METHOD: sqlite3_value
                   5790: **
                   5791: ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]
                   5792: ** object D and returns a pointer to that copy.  ^The [sqlite3_value] returned
                   5793: ** is a [protected sqlite3_value] object even if the input is not.
                   5794: ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a
1.6.2.1 ! misho    5795: ** memory allocation fails. ^If V is a [pointer value], then the result
        !          5796: ** of sqlite3_value_dup(V) is a NULL value.
1.4       misho    5797: **
                   5798: ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object
                   5799: ** previously obtained from [sqlite3_value_dup()].  ^If V is a NULL pointer
                   5800: ** then sqlite3_value_free(V) is a harmless no-op.
                   5801: */
                   5802: SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*);
                   5803: SQLITE_API void sqlite3_value_free(sqlite3_value*);
                   5804: 
                   5805: /*
1.2       misho    5806: ** CAPI3REF: Obtain Aggregate Function Context
1.4       misho    5807: ** METHOD: sqlite3_context
1.2       misho    5808: **
                   5809: ** Implementations of aggregate SQL functions use this
                   5810: ** routine to allocate memory for storing their state.
                   5811: **
1.5       misho    5812: ** ^The first time the sqlite3_aggregate_context(C,N) routine is called
                   5813: ** for a particular aggregate function, SQLite allocates
                   5814: ** N bytes of memory, zeroes out that memory, and returns a pointer
1.2       misho    5815: ** to the new memory. ^On second and subsequent calls to
                   5816: ** sqlite3_aggregate_context() for the same aggregate function instance,
                   5817: ** the same buffer is returned.  Sqlite3_aggregate_context() is normally
                   5818: ** called once for each invocation of the xStep callback and then one
                   5819: ** last time when the xFinal callback is invoked.  ^(When no rows match
                   5820: ** an aggregate query, the xStep() callback of the aggregate function
                   5821: ** implementation is never called and xFinal() is called exactly once.
                   5822: ** In those cases, sqlite3_aggregate_context() might be called for the
                   5823: ** first time from within xFinal().)^
                   5824: **
1.5       misho    5825: ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer
1.4       misho    5826: ** when first called if N is less than or equal to zero or if a memory
1.6.2.1 ! misho    5827: ** allocation error occurs.
1.2       misho    5828: **
                   5829: ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
                   5830: ** determined by the N parameter on first successful call.  Changing the
1.5       misho    5831: ** value of N in any subsequent call to sqlite3_aggregate_context() within
1.2       misho    5832: ** the same aggregate function instance will not resize the memory
1.4       misho    5833: ** allocation.)^  Within the xFinal callback, it is customary to set
1.5       misho    5834: ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no
1.4       misho    5835: ** pointless memory allocations occur.
1.2       misho    5836: **
1.5       misho    5837: ** ^SQLite automatically frees the memory allocated by
1.2       misho    5838: ** sqlite3_aggregate_context() when the aggregate query concludes.
                   5839: **
                   5840: ** The first parameter must be a copy of the
                   5841: ** [sqlite3_context | SQL function context] that is the first parameter
                   5842: ** to the xStep or xFinal callback routine that implements the aggregate
                   5843: ** function.
                   5844: **
                   5845: ** This routine must be called from the same thread in which
                   5846: ** the aggregate SQL function is running.
                   5847: */
                   5848: SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
                   5849: 
                   5850: /*
                   5851: ** CAPI3REF: User Data For Functions
1.4       misho    5852: ** METHOD: sqlite3_context
1.2       misho    5853: **
                   5854: ** ^The sqlite3_user_data() interface returns a copy of
                   5855: ** the pointer that was the pUserData parameter (the 5th parameter)
                   5856: ** of the [sqlite3_create_function()]
                   5857: ** and [sqlite3_create_function16()] routines that originally
                   5858: ** registered the application defined function.
                   5859: **
                   5860: ** This routine must be called from the same thread in which
                   5861: ** the application-defined function is running.
                   5862: */
                   5863: SQLITE_API void *sqlite3_user_data(sqlite3_context*);
                   5864: 
                   5865: /*
                   5866: ** CAPI3REF: Database Connection For Functions
1.4       misho    5867: ** METHOD: sqlite3_context
1.2       misho    5868: **
                   5869: ** ^The sqlite3_context_db_handle() interface returns a copy of
                   5870: ** the pointer to the [database connection] (the 1st parameter)
                   5871: ** of the [sqlite3_create_function()]
                   5872: ** and [sqlite3_create_function16()] routines that originally
                   5873: ** registered the application defined function.
                   5874: */
                   5875: SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
                   5876: 
                   5877: /*
                   5878: ** CAPI3REF: Function Auxiliary Data
1.4       misho    5879: ** METHOD: sqlite3_context
1.2       misho    5880: **
1.4       misho    5881: ** These functions may be used by (non-aggregate) SQL functions to
1.2       misho    5882: ** associate metadata with argument values. If the same value is passed to
                   5883: ** multiple invocations of the same SQL function during query execution, under
1.4       misho    5884: ** some circumstances the associated metadata may be preserved.  An example
                   5885: ** of where this might be useful is in a regular-expression matching
                   5886: ** function. The compiled version of the regular expression can be stored as
1.5       misho    5887: ** metadata associated with the pattern string.
1.4       misho    5888: ** Then as long as the pattern string remains the same,
                   5889: ** the compiled regular expression can be reused on multiple
                   5890: ** invocations of the same function.
1.2       misho    5891: **
1.5       misho    5892: ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the metadata
                   5893: ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument
                   5894: ** value to the application-defined function.  ^N is zero for the left-most
                   5895: ** function argument.  ^If there is no metadata
                   5896: ** associated with the function argument, the sqlite3_get_auxdata(C,N) interface
1.4       misho    5897: ** returns a NULL pointer.
                   5898: **
                   5899: ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
                   5900: ** argument of the application-defined function.  ^Subsequent
                   5901: ** calls to sqlite3_get_auxdata(C,N) return P from the most recent
                   5902: ** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
                   5903: ** NULL if the metadata has been discarded.
                   5904: ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
                   5905: ** SQLite will invoke the destructor function X with parameter P exactly
                   5906: ** once, when the metadata is discarded.
                   5907: ** SQLite is free to discard the metadata at any time, including: <ul>
                   5908: ** <li> ^(when the corresponding function parameter changes)^, or
                   5909: ** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
                   5910: **      SQL statement)^, or
                   5911: ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same
                   5912: **       parameter)^, or
1.5       misho    5913: ** <li> ^(during the original sqlite3_set_auxdata() call when a memory
1.4       misho    5914: **      allocation error occurs.)^ </ul>
                   5915: **
1.5       misho    5916: ** Note the last bullet in particular.  The destructor X in
1.4       misho    5917: ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
                   5918: ** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
                   5919: ** should be called near the end of the function implementation and the
                   5920: ** function implementation should not make any use of P after
                   5921: ** sqlite3_set_auxdata() has been called.
1.2       misho    5922: **
                   5923: ** ^(In practice, metadata is preserved between function calls for
1.4       misho    5924: ** function parameters that are compile-time constants, including literal
                   5925: ** values and [parameters] and expressions composed from the same.)^
1.2       misho    5926: **
1.5       misho    5927: ** The value of the N parameter to these interfaces should be non-negative.
                   5928: ** Future enhancements may make use of negative N values to define new
                   5929: ** kinds of function caching behavior.
                   5930: **
1.2       misho    5931: ** These routines must be called from the same thread in which
                   5932: ** the SQL function is running.
                   5933: */
                   5934: SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
                   5935: SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
                   5936: 
                   5937: 
                   5938: /*
                   5939: ** CAPI3REF: Constants Defining Special Destructor Behavior
                   5940: **
                   5941: ** These are special values for the destructor that is passed in as the
                   5942: ** final argument to routines like [sqlite3_result_blob()].  ^If the destructor
                   5943: ** argument is SQLITE_STATIC, it means that the content pointer is constant
                   5944: ** and will never change.  It does not need to be destroyed.  ^The
                   5945: ** SQLITE_TRANSIENT value means that the content will likely change in
                   5946: ** the near future and that SQLite should make its own private copy of
                   5947: ** the content before returning.
                   5948: **
                   5949: ** The typedef is necessary to work around problems in certain
1.4       misho    5950: ** C++ compilers.
1.2       misho    5951: */
                   5952: typedef void (*sqlite3_destructor_type)(void*);
                   5953: #define SQLITE_STATIC      ((sqlite3_destructor_type)0)
                   5954: #define SQLITE_TRANSIENT   ((sqlite3_destructor_type)-1)
                   5955: 
                   5956: /*
                   5957: ** CAPI3REF: Setting The Result Of An SQL Function
1.4       misho    5958: ** METHOD: sqlite3_context
1.2       misho    5959: **
                   5960: ** These routines are used by the xFunc or xFinal callbacks that
                   5961: ** implement SQL functions and aggregates.  See
                   5962: ** [sqlite3_create_function()] and [sqlite3_create_function16()]
                   5963: ** for additional information.
                   5964: **
                   5965: ** These functions work very much like the [parameter binding] family of
                   5966: ** functions used to bind values to host parameters in prepared statements.
                   5967: ** Refer to the [SQL parameter] documentation for additional information.
                   5968: **
                   5969: ** ^The sqlite3_result_blob() interface sets the result from
                   5970: ** an application-defined function to be the BLOB whose content is pointed
                   5971: ** to by the second parameter and which is N bytes long where N is the
                   5972: ** third parameter.
                   5973: **
1.4       misho    5974: ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)
                   5975: ** interfaces set the result of the application-defined function to be
                   5976: ** a BLOB containing all zero bytes and N bytes in size.
1.2       misho    5977: **
                   5978: ** ^The sqlite3_result_double() interface sets the result from
                   5979: ** an application-defined function to be a floating point value specified
                   5980: ** by its 2nd argument.
                   5981: **
                   5982: ** ^The sqlite3_result_error() and sqlite3_result_error16() functions
                   5983: ** cause the implemented SQL function to throw an exception.
                   5984: ** ^SQLite uses the string pointed to by the
                   5985: ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
                   5986: ** as the text of an error message.  ^SQLite interprets the error
                   5987: ** message string from sqlite3_result_error() as UTF-8. ^SQLite
1.5       misho    5988: ** interprets the string from sqlite3_result_error16() as UTF-16 using
                   5989: ** the same [byte-order determination rules] as [sqlite3_bind_text16()].
                   5990: ** ^If the third parameter to sqlite3_result_error()
1.2       misho    5991: ** or sqlite3_result_error16() is negative then SQLite takes as the error
                   5992: ** message all text up through the first zero character.
                   5993: ** ^If the third parameter to sqlite3_result_error() or
                   5994: ** sqlite3_result_error16() is non-negative then SQLite takes that many
                   5995: ** bytes (not characters) from the 2nd parameter as the error message.
                   5996: ** ^The sqlite3_result_error() and sqlite3_result_error16()
                   5997: ** routines make a private copy of the error message text before
                   5998: ** they return.  Hence, the calling function can deallocate or
                   5999: ** modify the text after they return without harm.
                   6000: ** ^The sqlite3_result_error_code() function changes the error code
                   6001: ** returned by SQLite as a result of an error in a function.  ^By default,
                   6002: ** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
                   6003: ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
                   6004: **
1.3       misho    6005: ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
                   6006: ** error indicating that a string or BLOB is too long to represent.
1.2       misho    6007: **
1.3       misho    6008: ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
                   6009: ** error indicating that a memory allocation failed.
1.2       misho    6010: **
                   6011: ** ^The sqlite3_result_int() interface sets the return value
                   6012: ** of the application-defined function to be the 32-bit signed integer
                   6013: ** value given in the 2nd argument.
                   6014: ** ^The sqlite3_result_int64() interface sets the return value
                   6015: ** of the application-defined function to be the 64-bit signed integer
                   6016: ** value given in the 2nd argument.
                   6017: **
                   6018: ** ^The sqlite3_result_null() interface sets the return value
                   6019: ** of the application-defined function to be NULL.
                   6020: **
                   6021: ** ^The sqlite3_result_text(), sqlite3_result_text16(),
                   6022: ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
                   6023: ** set the return value of the application-defined function to be
                   6024: ** a text string which is represented as UTF-8, UTF-16 native byte order,
                   6025: ** UTF-16 little endian, or UTF-16 big endian, respectively.
1.4       misho    6026: ** ^The sqlite3_result_text64() interface sets the return value of an
                   6027: ** application-defined function to be a text string in an encoding
                   6028: ** specified by the fifth (and last) parameter, which must be one
                   6029: ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
1.2       misho    6030: ** ^SQLite takes the text result from the application from
                   6031: ** the 2nd parameter of the sqlite3_result_text* interfaces.
1.6.2.1 ! misho    6032: ** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces
        !          6033: ** other than sqlite3_result_text64() is negative, then SQLite computes
        !          6034: ** the string length itself by searching the 2nd parameter for the first
        !          6035: ** zero character.
1.2       misho    6036: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
                   6037: ** is non-negative, then as many bytes (not characters) of the text
                   6038: ** pointed to by the 2nd parameter are taken as the application-defined
                   6039: ** function result.  If the 3rd parameter is non-negative, then it
                   6040: ** must be the byte offset into the string where the NUL terminator would
                   6041: ** appear if the string where NUL terminated.  If any NUL characters occur
                   6042: ** in the string at a byte offset that is less than the value of the 3rd
                   6043: ** parameter, then the resulting string will contain embedded NULs and the
                   6044: ** result of expressions operating on strings with embedded NULs is undefined.
                   6045: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
                   6046: ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
                   6047: ** function as the destructor on the text or BLOB result when it has
                   6048: ** finished using that result.
                   6049: ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
                   6050: ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
                   6051: ** assumes that the text or BLOB result is in constant space and does not
                   6052: ** copy the content of the parameter nor call a destructor on the content
                   6053: ** when it has finished using that result.
                   6054: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
                   6055: ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
1.5       misho    6056: ** then SQLite makes a copy of the result into space obtained
1.2       misho    6057: ** from [sqlite3_malloc()] before it returns.
                   6058: **
1.5       misho    6059: ** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and
                   6060: ** sqlite3_result_text16be() routines, and for sqlite3_result_text64()
                   6061: ** when the encoding is not UTF8, if the input UTF16 begins with a
                   6062: ** byte-order mark (BOM, U+FEFF) then the BOM is removed from the
                   6063: ** string and the rest of the string is interpreted according to the
                   6064: ** byte-order specified by the BOM.  ^The byte-order specified by
                   6065: ** the BOM at the beginning of the text overrides the byte-order
                   6066: ** specified by the interface procedure.  ^So, for example, if
                   6067: ** sqlite3_result_text16le() is invoked with text that begins
                   6068: ** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the
                   6069: ** first two bytes of input are skipped and the remaining input
                   6070: ** is interpreted as UTF16BE text.
                   6071: **
                   6072: ** ^For UTF16 input text to the sqlite3_result_text16(),
                   6073: ** sqlite3_result_text16be(), sqlite3_result_text16le(), and
                   6074: ** sqlite3_result_text64() routines, if the text contains invalid
                   6075: ** UTF16 characters, the invalid characters might be converted
                   6076: ** into the unicode replacement character, U+FFFD.
                   6077: **
1.2       misho    6078: ** ^The sqlite3_result_value() interface sets the result of
1.4       misho    6079: ** the application-defined function to be a copy of the
1.2       misho    6080: ** [unprotected sqlite3_value] object specified by the 2nd parameter.  ^The
                   6081: ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
                   6082: ** so that the [sqlite3_value] specified in the parameter may change or
                   6083: ** be deallocated after sqlite3_result_value() returns without harm.
                   6084: ** ^A [protected sqlite3_value] object may always be used where an
                   6085: ** [unprotected sqlite3_value] object is required, so either
                   6086: ** kind of [sqlite3_value] object can be used with this interface.
                   6087: **
1.5       misho    6088: ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an
                   6089: ** SQL NULL value, just like [sqlite3_result_null(C)], except that it
                   6090: ** also associates the host-language pointer P or type T with that
                   6091: ** NULL value such that the pointer can be retrieved within an
                   6092: ** [application-defined SQL function] using [sqlite3_value_pointer()].
                   6093: ** ^If the D parameter is not NULL, then it is a pointer to a destructor
                   6094: ** for the P parameter.  ^SQLite invokes D with P as its only argument
                   6095: ** when SQLite is finished with P.  The T parameter should be a static
                   6096: ** string and preferably a string literal. The sqlite3_result_pointer()
                   6097: ** routine is part of the [pointer passing interface] added for SQLite 3.20.0.
                   6098: **
1.2       misho    6099: ** If these routines are called from within the different thread
                   6100: ** than the one containing the application-defined function that received
                   6101: ** the [sqlite3_context] pointer, the results are undefined.
                   6102: */
                   6103: SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
1.4       misho    6104: SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*,
                   6105:                            sqlite3_uint64,void(*)(void*));
1.2       misho    6106: SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
                   6107: SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
                   6108: SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
                   6109: SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
                   6110: SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
                   6111: SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
                   6112: SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
                   6113: SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
                   6114: SQLITE_API void sqlite3_result_null(sqlite3_context*);
                   6115: SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
1.4       misho    6116: SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64,
                   6117:                            void(*)(void*), unsigned char encoding);
1.2       misho    6118: SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
                   6119: SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
                   6120: SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
                   6121: SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
1.5       misho    6122: SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*));
1.2       misho    6123: SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
1.4       misho    6124: SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n);
                   6125: 
                   6126: 
                   6127: /*
                   6128: ** CAPI3REF: Setting The Subtype Of An SQL Function
                   6129: ** METHOD: sqlite3_context
                   6130: **
                   6131: ** The sqlite3_result_subtype(C,T) function causes the subtype of
1.5       misho    6132: ** the result from the [application-defined SQL function] with
                   6133: ** [sqlite3_context] C to be the value T.  Only the lower 8 bits
1.4       misho    6134: ** of the subtype T are preserved in current versions of SQLite;
                   6135: ** higher order bits are discarded.
                   6136: ** The number of subtype bytes preserved by SQLite might increase
                   6137: ** in future releases of SQLite.
                   6138: */
                   6139: SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int);
1.2       misho    6140: 
                   6141: /*
                   6142: ** CAPI3REF: Define New Collating Sequences
1.4       misho    6143: ** METHOD: sqlite3
1.2       misho    6144: **
                   6145: ** ^These functions add, remove, or modify a [collation] associated
                   6146: ** with the [database connection] specified as the first argument.
                   6147: **
                   6148: ** ^The name of the collation is a UTF-8 string
                   6149: ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
                   6150: ** and a UTF-16 string in native byte order for sqlite3_create_collation16().
                   6151: ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
                   6152: ** considered to be the same name.
                   6153: **
                   6154: ** ^(The third argument (eTextRep) must be one of the constants:
                   6155: ** <ul>
                   6156: ** <li> [SQLITE_UTF8],
                   6157: ** <li> [SQLITE_UTF16LE],
                   6158: ** <li> [SQLITE_UTF16BE],
                   6159: ** <li> [SQLITE_UTF16], or
                   6160: ** <li> [SQLITE_UTF16_ALIGNED].
                   6161: ** </ul>)^
                   6162: ** ^The eTextRep argument determines the encoding of strings passed
1.5       misho    6163: ** to the collating function callback, xCompare.
1.2       misho    6164: ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
                   6165: ** force strings to be UTF16 with native byte order.
                   6166: ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
                   6167: ** on an even byte address.
                   6168: **
                   6169: ** ^The fourth argument, pArg, is an application data pointer that is passed
                   6170: ** through as the first argument to the collating function callback.
                   6171: **
1.5       misho    6172: ** ^The fifth argument, xCompare, is a pointer to the collating function.
1.2       misho    6173: ** ^Multiple collating functions can be registered using the same name but
                   6174: ** with different eTextRep parameters and SQLite will use whichever
                   6175: ** function requires the least amount of data transformation.
1.5       misho    6176: ** ^If the xCompare argument is NULL then the collating function is
1.2       misho    6177: ** deleted.  ^When all collating functions having the same name are deleted,
                   6178: ** that collation is no longer usable.
                   6179: **
1.5       misho    6180: ** ^The collating function callback is invoked with a copy of the pArg
1.2       misho    6181: ** application data pointer and with two strings in the encoding specified
1.5       misho    6182: ** by the eTextRep argument.  The two integer parameters to the collating
                   6183: ** function callback are the length of the two strings, in bytes. The collating
                   6184: ** function must return an integer that is negative, zero, or positive
1.2       misho    6185: ** if the first string is less than, equal to, or greater than the second,
                   6186: ** respectively.  A collating function must always return the same answer
                   6187: ** given the same inputs.  If two or more collating functions are registered
                   6188: ** to the same collation name (using different eTextRep values) then all
                   6189: ** must give an equivalent answer when invoked with equivalent strings.
                   6190: ** The collating function must obey the following properties for all
                   6191: ** strings A, B, and C:
                   6192: **
                   6193: ** <ol>
                   6194: ** <li> If A==B then B==A.
                   6195: ** <li> If A==B and B==C then A==C.
                   6196: ** <li> If A&lt;B THEN B&gt;A.
                   6197: ** <li> If A&lt;B and B&lt;C then A&lt;C.
                   6198: ** </ol>
                   6199: **
                   6200: ** If a collating function fails any of the above constraints and that
1.5       misho    6201: ** collating function is registered and used, then the behavior of SQLite
1.2       misho    6202: ** is undefined.
                   6203: **
                   6204: ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
                   6205: ** with the addition that the xDestroy callback is invoked on pArg when
                   6206: ** the collating function is deleted.
                   6207: ** ^Collating functions are deleted when they are overridden by later
                   6208: ** calls to the collation creation functions or when the
                   6209: ** [database connection] is closed using [sqlite3_close()].
                   6210: **
1.5       misho    6211: ** ^The xDestroy callback is <u>not</u> called if the
1.2       misho    6212: ** sqlite3_create_collation_v2() function fails.  Applications that invoke
1.5       misho    6213: ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
1.2       misho    6214: ** check the return code and dispose of the application data pointer
                   6215: ** themselves rather than expecting SQLite to deal with it for them.
1.5       misho    6216: ** This is different from every other SQLite interface.  The inconsistency
                   6217: ** is unfortunate but cannot be changed without breaking backwards
1.2       misho    6218: ** compatibility.
                   6219: **
                   6220: ** See also:  [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
                   6221: */
                   6222: SQLITE_API int sqlite3_create_collation(
1.5       misho    6223:   sqlite3*,
                   6224:   const char *zName,
                   6225:   int eTextRep,
1.2       misho    6226:   void *pArg,
                   6227:   int(*xCompare)(void*,int,const void*,int,const void*)
                   6228: );
                   6229: SQLITE_API int sqlite3_create_collation_v2(
1.5       misho    6230:   sqlite3*,
                   6231:   const char *zName,
                   6232:   int eTextRep,
1.2       misho    6233:   void *pArg,
                   6234:   int(*xCompare)(void*,int,const void*,int,const void*),
                   6235:   void(*xDestroy)(void*)
                   6236: );
                   6237: SQLITE_API int sqlite3_create_collation16(
1.5       misho    6238:   sqlite3*,
1.2       misho    6239:   const void *zName,
1.5       misho    6240:   int eTextRep,
1.2       misho    6241:   void *pArg,
                   6242:   int(*xCompare)(void*,int,const void*,int,const void*)
                   6243: );
                   6244: 
                   6245: /*
                   6246: ** CAPI3REF: Collation Needed Callbacks
1.4       misho    6247: ** METHOD: sqlite3
1.2       misho    6248: **
                   6249: ** ^To avoid having to register all collation sequences before a database
                   6250: ** can be used, a single callback function may be registered with the
                   6251: ** [database connection] to be invoked whenever an undefined collation
                   6252: ** sequence is required.
                   6253: **
                   6254: ** ^If the function is registered using the sqlite3_collation_needed() API,
                   6255: ** then it is passed the names of undefined collation sequences as strings
                   6256: ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
                   6257: ** the names are passed as UTF-16 in machine native byte order.
                   6258: ** ^A call to either function replaces the existing collation-needed callback.
                   6259: **
                   6260: ** ^(When the callback is invoked, the first argument passed is a copy
                   6261: ** of the second argument to sqlite3_collation_needed() or
                   6262: ** sqlite3_collation_needed16().  The second argument is the database
                   6263: ** connection.  The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
                   6264: ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
                   6265: ** sequence function required.  The fourth parameter is the name of the
                   6266: ** required collation sequence.)^
                   6267: **
                   6268: ** The callback function should register the desired collation using
                   6269: ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
                   6270: ** [sqlite3_create_collation_v2()].
                   6271: */
                   6272: SQLITE_API int sqlite3_collation_needed(
1.5       misho    6273:   sqlite3*,
                   6274:   void*,
1.2       misho    6275:   void(*)(void*,sqlite3*,int eTextRep,const char*)
                   6276: );
                   6277: SQLITE_API int sqlite3_collation_needed16(
1.5       misho    6278:   sqlite3*,
1.2       misho    6279:   void*,
                   6280:   void(*)(void*,sqlite3*,int eTextRep,const void*)
                   6281: );
                   6282: 
                   6283: #ifdef SQLITE_ENABLE_CEROD
                   6284: /*
1.5       misho    6285: ** Specify the activation key for a CEROD database.  Unless
1.2       misho    6286: ** activated, none of the CEROD routines will work.
                   6287: */
                   6288: SQLITE_API void sqlite3_activate_cerod(
                   6289:   const char *zPassPhrase        /* Activation phrase */
                   6290: );
                   6291: #endif
                   6292: 
                   6293: /*
                   6294: ** CAPI3REF: Suspend Execution For A Short Time
                   6295: **
                   6296: ** The sqlite3_sleep() function causes the current thread to suspend execution
                   6297: ** for at least a number of milliseconds specified in its parameter.
                   6298: **
                   6299: ** If the operating system does not support sleep requests with
                   6300: ** millisecond time resolution, then the time will be rounded up to
                   6301: ** the nearest second. The number of milliseconds of sleep actually
                   6302: ** requested from the operating system is returned.
                   6303: **
                   6304: ** ^SQLite implements this interface by calling the xSleep()
                   6305: ** method of the default [sqlite3_vfs] object.  If the xSleep() method
                   6306: ** of the default VFS is not implemented correctly, or not implemented at
                   6307: ** all, then the behavior of sqlite3_sleep() may deviate from the description
                   6308: ** in the previous paragraphs.
1.6.2.1 ! misho    6309: **
        !          6310: ** If a negative argument is passed to sqlite3_sleep() the results vary by
        !          6311: ** VFS and operating system.  Some system treat a negative argument as an
        !          6312: ** instruction to sleep forever.  Others understand it to mean do not sleep
        !          6313: ** at all. ^In SQLite version 3.42.0 and later, a negative
        !          6314: ** argument passed into sqlite3_sleep() is changed to zero before it is relayed
        !          6315: ** down into the xSleep method of the VFS.
1.2       misho    6316: */
                   6317: SQLITE_API int sqlite3_sleep(int);
                   6318: 
                   6319: /*
                   6320: ** CAPI3REF: Name Of The Folder Holding Temporary Files
                   6321: **
                   6322: ** ^(If this global variable is made to point to a string which is
                   6323: ** the name of a folder (a.k.a. directory), then all temporary files
                   6324: ** created by SQLite when using a built-in [sqlite3_vfs | VFS]
                   6325: ** will be placed in that directory.)^  ^If this variable
                   6326: ** is a NULL pointer, then SQLite performs a search for an appropriate
                   6327: ** temporary file directory.
                   6328: **
1.4       misho    6329: ** Applications are strongly discouraged from using this global variable.
                   6330: ** It is required to set a temporary folder on Windows Runtime (WinRT).
                   6331: ** But for all other platforms, it is highly recommended that applications
                   6332: ** neither read nor write this variable.  This global variable is a relic
                   6333: ** that exists for backwards compatibility of legacy applications and should
                   6334: ** be avoided in new projects.
                   6335: **
1.2       misho    6336: ** It is not safe to read or modify this variable in more than one
                   6337: ** thread at a time.  It is not safe to read or modify this variable
                   6338: ** if a [database connection] is being used at the same time in a separate
                   6339: ** thread.
                   6340: ** It is intended that this variable be set once
                   6341: ** as part of process initialization and before any SQLite interface
                   6342: ** routines have been called and that this variable remain unchanged
                   6343: ** thereafter.
                   6344: **
                   6345: ** ^The [temp_store_directory pragma] may modify this variable and cause
                   6346: ** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
                   6347: ** the [temp_store_directory pragma] always assumes that any string
1.5       misho    6348: ** that this variable points to is held in memory obtained from
1.2       misho    6349: ** [sqlite3_malloc] and the pragma may attempt to free that memory
                   6350: ** using [sqlite3_free].
                   6351: ** Hence, if this variable is modified directly, either it should be
                   6352: ** made NULL or made to point to memory obtained from [sqlite3_malloc]
                   6353: ** or else the use of the [temp_store_directory pragma] should be avoided.
1.4       misho    6354: ** Except when requested by the [temp_store_directory pragma], SQLite
                   6355: ** does not free the memory that sqlite3_temp_directory points to.  If
                   6356: ** the application wants that memory to be freed, it must do
                   6357: ** so itself, taking care to only do so after all [database connection]
                   6358: ** objects have been destroyed.
1.3       misho    6359: **
                   6360: ** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
                   6361: ** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
                   6362: ** features that require the use of temporary files may fail.  Here is an
                   6363: ** example of how to do this using C++ with the Windows Runtime:
                   6364: **
                   6365: ** <blockquote><pre>
                   6366: ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
                   6367: ** &nbsp;     TemporaryFolder->Path->Data();
                   6368: ** char zPathBuf&#91;MAX_PATH + 1&#93;;
                   6369: ** memset(zPathBuf, 0, sizeof(zPathBuf));
                   6370: ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
                   6371: ** &nbsp;     NULL, NULL);
                   6372: ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
                   6373: ** </pre></blockquote>
1.2       misho    6374: */
                   6375: SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
                   6376: 
                   6377: /*
1.3       misho    6378: ** CAPI3REF: Name Of The Folder Holding Database Files
                   6379: **
                   6380: ** ^(If this global variable is made to point to a string which is
                   6381: ** the name of a folder (a.k.a. directory), then all database files
                   6382: ** specified with a relative pathname and created or accessed by
                   6383: ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed
                   6384: ** to be relative to that directory.)^ ^If this variable is a NULL
                   6385: ** pointer, then SQLite assumes that all database files specified
                   6386: ** with a relative pathname are relative to the current directory
                   6387: ** for the process.  Only the windows VFS makes use of this global
                   6388: ** variable; it is ignored by the unix VFS.
                   6389: **
                   6390: ** Changing the value of this variable while a database connection is
                   6391: ** open can result in a corrupt database.
                   6392: **
                   6393: ** It is not safe to read or modify this variable in more than one
                   6394: ** thread at a time.  It is not safe to read or modify this variable
                   6395: ** if a [database connection] is being used at the same time in a separate
                   6396: ** thread.
                   6397: ** It is intended that this variable be set once
                   6398: ** as part of process initialization and before any SQLite interface
                   6399: ** routines have been called and that this variable remain unchanged
                   6400: ** thereafter.
                   6401: **
                   6402: ** ^The [data_store_directory pragma] may modify this variable and cause
                   6403: ** it to point to memory obtained from [sqlite3_malloc].  ^Furthermore,
                   6404: ** the [data_store_directory pragma] always assumes that any string
1.5       misho    6405: ** that this variable points to is held in memory obtained from
1.3       misho    6406: ** [sqlite3_malloc] and the pragma may attempt to free that memory
                   6407: ** using [sqlite3_free].
                   6408: ** Hence, if this variable is modified directly, either it should be
                   6409: ** made NULL or made to point to memory obtained from [sqlite3_malloc]
                   6410: ** or else the use of the [data_store_directory pragma] should be avoided.
                   6411: */
                   6412: SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory;
                   6413: 
                   6414: /*
1.5       misho    6415: ** CAPI3REF: Win32 Specific Interface
                   6416: **
                   6417: ** These interfaces are available only on Windows.  The
                   6418: ** [sqlite3_win32_set_directory] interface is used to set the value associated
                   6419: ** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to
                   6420: ** zValue, depending on the value of the type parameter.  The zValue parameter
                   6421: ** should be NULL to cause the previous value to be freed via [sqlite3_free];
                   6422: ** a non-NULL value will be copied into memory obtained from [sqlite3_malloc]
                   6423: ** prior to being used.  The [sqlite3_win32_set_directory] interface returns
                   6424: ** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported,
                   6425: ** or [SQLITE_NOMEM] if memory could not be allocated.  The value of the
                   6426: ** [sqlite3_data_directory] variable is intended to act as a replacement for
                   6427: ** the current directory on the sub-platforms of Win32 where that concept is
                   6428: ** not present, e.g. WinRT and UWP.  The [sqlite3_win32_set_directory8] and
                   6429: ** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the
                   6430: ** sqlite3_win32_set_directory interface except the string parameter must be
                   6431: ** UTF-8 or UTF-16, respectively.
                   6432: */
                   6433: SQLITE_API int sqlite3_win32_set_directory(
                   6434:   unsigned long type, /* Identifier for directory being set or reset */
                   6435:   void *zValue        /* New value for directory being set or reset */
                   6436: );
                   6437: SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue);
                   6438: SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue);
                   6439: 
                   6440: /*
                   6441: ** CAPI3REF: Win32 Directory Types
                   6442: **
                   6443: ** These macros are only available on Windows.  They define the allowed values
                   6444: ** for the type argument to the [sqlite3_win32_set_directory] interface.
                   6445: */
                   6446: #define SQLITE_WIN32_DATA_DIRECTORY_TYPE  1
                   6447: #define SQLITE_WIN32_TEMP_DIRECTORY_TYPE  2
                   6448: 
                   6449: /*
1.2       misho    6450: ** CAPI3REF: Test For Auto-Commit Mode
                   6451: ** KEYWORDS: {autocommit mode}
1.4       misho    6452: ** METHOD: sqlite3
1.2       misho    6453: **
                   6454: ** ^The sqlite3_get_autocommit() interface returns non-zero or
                   6455: ** zero if the given database connection is or is not in autocommit mode,
                   6456: ** respectively.  ^Autocommit mode is on by default.
                   6457: ** ^Autocommit mode is disabled by a [BEGIN] statement.
                   6458: ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
                   6459: **
                   6460: ** If certain kinds of errors occur on a statement within a multi-statement
                   6461: ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
                   6462: ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
                   6463: ** transaction might be rolled back automatically.  The only way to
                   6464: ** find out whether SQLite automatically rolled back the transaction after
                   6465: ** an error is to use this function.
                   6466: **
                   6467: ** If another thread changes the autocommit status of the database
                   6468: ** connection while this routine is running, then the return value
                   6469: ** is undefined.
                   6470: */
                   6471: SQLITE_API int sqlite3_get_autocommit(sqlite3*);
                   6472: 
                   6473: /*
                   6474: ** CAPI3REF: Find The Database Handle Of A Prepared Statement
1.4       misho    6475: ** METHOD: sqlite3_stmt
1.2       misho    6476: **
                   6477: ** ^The sqlite3_db_handle interface returns the [database connection] handle
                   6478: ** to which a [prepared statement] belongs.  ^The [database connection]
                   6479: ** returned by sqlite3_db_handle is the same [database connection]
                   6480: ** that was the first argument
                   6481: ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
                   6482: ** create the statement in the first place.
                   6483: */
                   6484: SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
                   6485: 
                   6486: /*
1.6.2.1 ! misho    6487: ** CAPI3REF: Return The Schema Name For A Database Connection
        !          6488: ** METHOD: sqlite3
        !          6489: **
        !          6490: ** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name
        !          6491: ** for the N-th database on database connection D, or a NULL pointer of N is
        !          6492: ** out of range.  An N value of 0 means the main database file.  An N of 1 is
        !          6493: ** the "temp" schema.  Larger values of N correspond to various ATTACH-ed
        !          6494: ** databases.
        !          6495: **
        !          6496: ** Space to hold the string that is returned by sqlite3_db_name() is managed
        !          6497: ** by SQLite itself.  The string might be deallocated by any operation that
        !          6498: ** changes the schema, including [ATTACH] or [DETACH] or calls to
        !          6499: ** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that
        !          6500: ** occur on a different thread.  Applications that need to
        !          6501: ** remember the string long-term should make their own copy.  Applications that
        !          6502: ** are accessing the same database connection simultaneously on multiple
        !          6503: ** threads should mutex-protect calls to this API and should make their own
        !          6504: ** private copy of the result prior to releasing the mutex.
        !          6505: */
        !          6506: SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N);
        !          6507: 
        !          6508: /*
1.2       misho    6509: ** CAPI3REF: Return The Filename For A Database Connection
1.4       misho    6510: ** METHOD: sqlite3
1.2       misho    6511: **
1.5       misho    6512: ** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename
                   6513: ** associated with database N of connection D.
                   6514: ** ^If there is no attached database N on the database
1.2       misho    6515: ** connection D, or if database N is a temporary or in-memory database, then
1.5       misho    6516: ** this function will return either a NULL pointer or an empty string.
                   6517: **
                   6518: ** ^The string value returned by this routine is owned and managed by
                   6519: ** the database connection.  ^The value will be valid until the database N
                   6520: ** is [DETACH]-ed or until the database connection closes.
1.2       misho    6521: **
                   6522: ** ^The filename returned by this function is the output of the
                   6523: ** xFullPathname method of the [VFS].  ^In other words, the filename
                   6524: ** will be an absolute pathname, even if the filename used
                   6525: ** to open the database originally was a URI or relative pathname.
1.5       misho    6526: **
                   6527: ** If the filename pointer returned by this routine is not NULL, then it
                   6528: ** can be used as the filename input parameter to these routines:
                   6529: ** <ul>
                   6530: ** <li> [sqlite3_uri_parameter()]
                   6531: ** <li> [sqlite3_uri_boolean()]
                   6532: ** <li> [sqlite3_uri_int64()]
                   6533: ** <li> [sqlite3_filename_database()]
                   6534: ** <li> [sqlite3_filename_journal()]
                   6535: ** <li> [sqlite3_filename_wal()]
                   6536: ** </ul>
1.2       misho    6537: */
1.6.2.1 ! misho    6538: SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName);
1.2       misho    6539: 
                   6540: /*
1.3       misho    6541: ** CAPI3REF: Determine if a database is read-only
1.4       misho    6542: ** METHOD: sqlite3
1.3       misho    6543: **
                   6544: ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
                   6545: ** of connection D is read-only, 0 if it is read/write, or -1 if N is not
                   6546: ** the name of a database on connection D.
                   6547: */
                   6548: SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName);
                   6549: 
                   6550: /*
1.6       misho    6551: ** CAPI3REF: Determine the transaction state of a database
                   6552: ** METHOD: sqlite3
                   6553: **
                   6554: ** ^The sqlite3_txn_state(D,S) interface returns the current
                   6555: ** [transaction state] of schema S in database connection D.  ^If S is NULL,
                   6556: ** then the highest transaction state of any schema on database connection D
                   6557: ** is returned.  Transaction states are (in order of lowest to highest):
                   6558: ** <ol>
                   6559: ** <li value="0"> SQLITE_TXN_NONE
                   6560: ** <li value="1"> SQLITE_TXN_READ
                   6561: ** <li value="2"> SQLITE_TXN_WRITE
                   6562: ** </ol>
                   6563: ** ^If the S argument to sqlite3_txn_state(D,S) is not the name of
                   6564: ** a valid schema, then -1 is returned.
                   6565: */
                   6566: SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema);
                   6567: 
                   6568: /*
                   6569: ** CAPI3REF: Allowed return values from [sqlite3_txn_state()]
                   6570: ** KEYWORDS: {transaction state}
                   6571: **
                   6572: ** These constants define the current transaction state of a database file.
                   6573: ** ^The [sqlite3_txn_state(D,S)] interface returns one of these
                   6574: ** constants in order to describe the transaction state of schema S
                   6575: ** in [database connection] D.
                   6576: **
                   6577: ** <dl>
                   6578: ** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt>
                   6579: ** <dd>The SQLITE_TXN_NONE state means that no transaction is currently
                   6580: ** pending.</dd>
                   6581: **
                   6582: ** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt>
                   6583: ** <dd>The SQLITE_TXN_READ state means that the database is currently
                   6584: ** in a read transaction.  Content has been read from the database file
                   6585: ** but nothing in the database file has changed.  The transaction state
                   6586: ** will advanced to SQLITE_TXN_WRITE if any changes occur and there are
                   6587: ** no other conflicting concurrent write transactions.  The transaction
                   6588: ** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or
                   6589: ** [COMMIT].</dd>
                   6590: **
                   6591: ** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt>
                   6592: ** <dd>The SQLITE_TXN_WRITE state means that the database is currently
                   6593: ** in a write transaction.  Content has been written to the database file
                   6594: ** but has not yet committed.  The transaction state will change to
                   6595: ** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd>
                   6596: */
                   6597: #define SQLITE_TXN_NONE  0
                   6598: #define SQLITE_TXN_READ  1
                   6599: #define SQLITE_TXN_WRITE 2
                   6600: 
                   6601: /*
1.2       misho    6602: ** CAPI3REF: Find the next prepared statement
1.4       misho    6603: ** METHOD: sqlite3
1.2       misho    6604: **
                   6605: ** ^This interface returns a pointer to the next [prepared statement] after
                   6606: ** pStmt associated with the [database connection] pDb.  ^If pStmt is NULL
                   6607: ** then this interface returns a pointer to the first prepared statement
                   6608: ** associated with the database connection pDb.  ^If no prepared statement
                   6609: ** satisfies the conditions of this routine, it returns NULL.
                   6610: **
                   6611: ** The [database connection] pointer D in a call to
                   6612: ** [sqlite3_next_stmt(D,S)] must refer to an open database
                   6613: ** connection and in particular must not be a NULL pointer.
                   6614: */
                   6615: SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
                   6616: 
                   6617: /*
                   6618: ** CAPI3REF: Commit And Rollback Notification Callbacks
1.4       misho    6619: ** METHOD: sqlite3
1.2       misho    6620: **
                   6621: ** ^The sqlite3_commit_hook() interface registers a callback
                   6622: ** function to be invoked whenever a transaction is [COMMIT | committed].
                   6623: ** ^Any callback set by a previous call to sqlite3_commit_hook()
                   6624: ** for the same database connection is overridden.
                   6625: ** ^The sqlite3_rollback_hook() interface registers a callback
                   6626: ** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
                   6627: ** ^Any callback set by a previous call to sqlite3_rollback_hook()
                   6628: ** for the same database connection is overridden.
                   6629: ** ^The pArg argument is passed through to the callback.
                   6630: ** ^If the callback on a commit hook function returns non-zero,
                   6631: ** then the commit is converted into a rollback.
                   6632: **
                   6633: ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
                   6634: ** return the P argument from the previous call of the same function
                   6635: ** on the same [database connection] D, or NULL for
                   6636: ** the first call for each function on D.
                   6637: **
                   6638: ** The commit and rollback hook callbacks are not reentrant.
                   6639: ** The callback implementation must not do anything that will modify
                   6640: ** the database connection that invoked the callback.  Any actions
                   6641: ** to modify the database connection must be deferred until after the
                   6642: ** completion of the [sqlite3_step()] call that triggered the commit
                   6643: ** or rollback hook in the first place.
                   6644: ** Note that running any other SQL statements, including SELECT statements,
                   6645: ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
                   6646: ** the database connections for the meaning of "modify" in this paragraph.
                   6647: **
                   6648: ** ^Registering a NULL function disables the callback.
                   6649: **
                   6650: ** ^When the commit hook callback routine returns zero, the [COMMIT]
                   6651: ** operation is allowed to continue normally.  ^If the commit hook
                   6652: ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
                   6653: ** ^The rollback hook is invoked on a rollback that results from a commit
                   6654: ** hook returning non-zero, just as it would be with any other rollback.
                   6655: **
                   6656: ** ^For the purposes of this API, a transaction is said to have been
                   6657: ** rolled back if an explicit "ROLLBACK" statement is executed, or
                   6658: ** an error or constraint causes an implicit rollback to occur.
                   6659: ** ^The rollback callback is not invoked if a transaction is
                   6660: ** automatically rolled back because the database connection is closed.
                   6661: **
                   6662: ** See also the [sqlite3_update_hook()] interface.
                   6663: */
                   6664: SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
                   6665: SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
                   6666: 
                   6667: /*
1.6.2.1 ! misho    6668: ** CAPI3REF: Autovacuum Compaction Amount Callback
        !          6669: ** METHOD: sqlite3
        !          6670: **
        !          6671: ** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback
        !          6672: ** function C that is invoked prior to each autovacuum of the database
        !          6673: ** file.  ^The callback is passed a copy of the generic data pointer (P),
        !          6674: ** the schema-name of the attached database that is being autovacuumed,
        !          6675: ** the size of the database file in pages, the number of free pages,
        !          6676: ** and the number of bytes per page, respectively.  The callback should
        !          6677: ** return the number of free pages that should be removed by the
        !          6678: ** autovacuum.  ^If the callback returns zero, then no autovacuum happens.
        !          6679: ** ^If the value returned is greater than or equal to the number of
        !          6680: ** free pages, then a complete autovacuum happens.
        !          6681: **
        !          6682: ** <p>^If there are multiple ATTACH-ed database files that are being
        !          6683: ** modified as part of a transaction commit, then the autovacuum pages
        !          6684: ** callback is invoked separately for each file.
        !          6685: **
        !          6686: ** <p><b>The callback is not reentrant.</b> The callback function should
        !          6687: ** not attempt to invoke any other SQLite interface.  If it does, bad
        !          6688: ** things may happen, including segmentation faults and corrupt database
        !          6689: ** files.  The callback function should be a simple function that
        !          6690: ** does some arithmetic on its input parameters and returns a result.
        !          6691: **
        !          6692: ** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional
        !          6693: ** destructor for the P parameter.  ^If X is not NULL, then X(P) is
        !          6694: ** invoked whenever the database connection closes or when the callback
        !          6695: ** is overwritten by another invocation of sqlite3_autovacuum_pages().
        !          6696: **
        !          6697: ** <p>^There is only one autovacuum pages callback per database connection.
        !          6698: ** ^Each call to the sqlite3_autovacuum_pages() interface overrides all
        !          6699: ** previous invocations for that database connection.  ^If the callback
        !          6700: ** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer,
        !          6701: ** then the autovacuum steps callback is cancelled.  The return value
        !          6702: ** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might
        !          6703: ** be some other error code if something goes wrong.  The current
        !          6704: ** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other
        !          6705: ** return codes might be added in future releases.
        !          6706: **
        !          6707: ** <p>If no autovacuum pages callback is specified (the usual case) or
        !          6708: ** a NULL pointer is provided for the callback,
        !          6709: ** then the default behavior is to vacuum all free pages.  So, in other
        !          6710: ** words, the default behavior is the same as if the callback function
        !          6711: ** were something like this:
        !          6712: **
        !          6713: ** <blockquote><pre>
        !          6714: ** &nbsp;   unsigned int demonstration_autovac_pages_callback(
        !          6715: ** &nbsp;     void *pClientData,
        !          6716: ** &nbsp;     const char *zSchema,
        !          6717: ** &nbsp;     unsigned int nDbPage,
        !          6718: ** &nbsp;     unsigned int nFreePage,
        !          6719: ** &nbsp;     unsigned int nBytePerPage
        !          6720: ** &nbsp;   ){
        !          6721: ** &nbsp;     return nFreePage;
        !          6722: ** &nbsp;   }
        !          6723: ** </pre></blockquote>
        !          6724: */
        !          6725: SQLITE_API int sqlite3_autovacuum_pages(
        !          6726:   sqlite3 *db,
        !          6727:   unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int),
        !          6728:   void*,
        !          6729:   void(*)(void*)
        !          6730: );
        !          6731: 
        !          6732: 
        !          6733: /*
1.2       misho    6734: ** CAPI3REF: Data Change Notification Callbacks
1.4       misho    6735: ** METHOD: sqlite3
1.2       misho    6736: **
                   6737: ** ^The sqlite3_update_hook() interface registers a callback function
                   6738: ** with the [database connection] identified by the first argument
1.4       misho    6739: ** to be invoked whenever a row is updated, inserted or deleted in
                   6740: ** a [rowid table].
1.2       misho    6741: ** ^Any callback set by a previous call to this function
                   6742: ** for the same database connection is overridden.
                   6743: **
                   6744: ** ^The second argument is a pointer to the function to invoke when a
1.4       misho    6745: ** row is updated, inserted or deleted in a rowid table.
1.2       misho    6746: ** ^The first argument to the callback is a copy of the third argument
                   6747: ** to sqlite3_update_hook().
                   6748: ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
                   6749: ** or [SQLITE_UPDATE], depending on the operation that caused the callback
                   6750: ** to be invoked.
                   6751: ** ^The third and fourth arguments to the callback contain pointers to the
                   6752: ** database and table name containing the affected row.
                   6753: ** ^The final callback parameter is the [rowid] of the row.
                   6754: ** ^In the case of an update, this is the [rowid] after the update takes place.
                   6755: **
                   6756: ** ^(The update hook is not invoked when internal system tables are
1.5       misho    6757: ** modified (i.e. sqlite_sequence).)^
1.4       misho    6758: ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.
1.2       misho    6759: **
                   6760: ** ^In the current implementation, the update hook
1.5       misho    6761: ** is not invoked when conflicting rows are deleted because of an
1.2       misho    6762: ** [ON CONFLICT | ON CONFLICT REPLACE] clause.  ^Nor is the update hook
                   6763: ** invoked when rows are deleted using the [truncate optimization].
                   6764: ** The exceptions defined in this paragraph might change in a future
                   6765: ** release of SQLite.
                   6766: **
                   6767: ** The update hook implementation must not do anything that will modify
                   6768: ** the database connection that invoked the update hook.  Any actions
                   6769: ** to modify the database connection must be deferred until after the
                   6770: ** completion of the [sqlite3_step()] call that triggered the update hook.
                   6771: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
                   6772: ** database connections for the meaning of "modify" in this paragraph.
                   6773: **
                   6774: ** ^The sqlite3_update_hook(D,C,P) function
                   6775: ** returns the P argument from the previous call
                   6776: ** on the same [database connection] D, or NULL for
                   6777: ** the first call on D.
                   6778: **
1.4       misho    6779: ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],
                   6780: ** and [sqlite3_preupdate_hook()] interfaces.
1.2       misho    6781: */
                   6782: SQLITE_API void *sqlite3_update_hook(
1.5       misho    6783:   sqlite3*,
1.2       misho    6784:   void(*)(void *,int ,char const *,char const *,sqlite3_int64),
                   6785:   void*
                   6786: );
                   6787: 
                   6788: /*
                   6789: ** CAPI3REF: Enable Or Disable Shared Pager Cache
                   6790: **
                   6791: ** ^(This routine enables or disables the sharing of the database cache
                   6792: ** and schema data structures between [database connection | connections]
                   6793: ** to the same database. Sharing is enabled if the argument is true
                   6794: ** and disabled if the argument is false.)^
                   6795: **
1.6.2.1 ! misho    6796: ** This interface is omitted if SQLite is compiled with
        !          6797: ** [-DSQLITE_OMIT_SHARED_CACHE].  The [-DSQLITE_OMIT_SHARED_CACHE]
        !          6798: ** compile-time option is recommended because the
        !          6799: ** [use of shared cache mode is discouraged].
        !          6800: **
1.2       misho    6801: ** ^Cache sharing is enabled and disabled for an entire process.
1.5       misho    6802: ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]).
                   6803: ** In prior versions of SQLite,
1.2       misho    6804: ** sharing was enabled or disabled for each thread separately.
                   6805: **
                   6806: ** ^(The cache sharing mode set by this interface effects all subsequent
                   6807: ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
1.5       misho    6808: ** Existing database connections continue to use the sharing mode
1.2       misho    6809: ** that was in effect at the time they were opened.)^
                   6810: **
                   6811: ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
                   6812: ** successfully.  An [error code] is returned otherwise.)^
                   6813: **
1.5       misho    6814: ** ^Shared cache is disabled by default. It is recommended that it stay
                   6815: ** that way.  In other words, do not use this routine.  This interface
                   6816: ** continues to be provided for historical compatibility, but its use is
                   6817: ** discouraged.  Any use of shared cache is discouraged.  If shared cache
                   6818: ** must be used, it is recommended that shared cache only be enabled for
                   6819: ** individual database connections using the [sqlite3_open_v2()] interface
                   6820: ** with the [SQLITE_OPEN_SHAREDCACHE] flag.
1.2       misho    6821: **
1.4       misho    6822: ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0
1.5       misho    6823: ** and will always return SQLITE_MISUSE. On those systems,
                   6824: ** shared cache mode should be enabled per-database connection via
1.4       misho    6825: ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].
                   6826: **
1.3       misho    6827: ** This interface is threadsafe on processors where writing a
                   6828: ** 32-bit integer is atomic.
                   6829: **
1.2       misho    6830: ** See Also:  [SQLite Shared-Cache Mode]
                   6831: */
                   6832: SQLITE_API int sqlite3_enable_shared_cache(int);
                   6833: 
                   6834: /*
                   6835: ** CAPI3REF: Attempt To Free Heap Memory
                   6836: **
                   6837: ** ^The sqlite3_release_memory() interface attempts to free N bytes
                   6838: ** of heap memory by deallocating non-essential memory allocations
                   6839: ** held by the database library.   Memory used to cache database
                   6840: ** pages to improve performance is an example of non-essential memory.
                   6841: ** ^sqlite3_release_memory() returns the number of bytes actually freed,
                   6842: ** which might be more or less than the amount requested.
                   6843: ** ^The sqlite3_release_memory() routine is a no-op returning zero
                   6844: ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
                   6845: **
                   6846: ** See also: [sqlite3_db_release_memory()]
                   6847: */
                   6848: SQLITE_API int sqlite3_release_memory(int);
                   6849: 
                   6850: /*
                   6851: ** CAPI3REF: Free Memory Used By A Database Connection
1.4       misho    6852: ** METHOD: sqlite3
1.2       misho    6853: **
                   6854: ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
                   6855: ** memory as possible from database connection D. Unlike the
1.4       misho    6856: ** [sqlite3_release_memory()] interface, this interface is in effect even
                   6857: ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
1.2       misho    6858: ** omitted.
                   6859: **
                   6860: ** See also: [sqlite3_release_memory()]
                   6861: */
                   6862: SQLITE_API int sqlite3_db_release_memory(sqlite3*);
                   6863: 
                   6864: /*
                   6865: ** CAPI3REF: Impose A Limit On Heap Size
                   6866: **
1.5       misho    6867: ** These interfaces impose limits on the amount of heap memory that will be
                   6868: ** by all database connections within a single process.
                   6869: **
1.2       misho    6870: ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
                   6871: ** soft limit on the amount of heap memory that may be allocated by SQLite.
                   6872: ** ^SQLite strives to keep heap memory utilization below the soft heap
                   6873: ** limit by reducing the number of pages held in the page cache
                   6874: ** as heap memory usages approaches the limit.
                   6875: ** ^The soft heap limit is "soft" because even though SQLite strives to stay
                   6876: ** below the limit, it will exceed the limit rather than generate
1.5       misho    6877: ** an [SQLITE_NOMEM] error.  In other words, the soft heap limit
1.2       misho    6878: ** is advisory only.
                   6879: **
1.5       misho    6880: ** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of
                   6881: ** N bytes on the amount of memory that will be allocated.  ^The
                   6882: ** sqlite3_hard_heap_limit64(N) interface is similar to
                   6883: ** sqlite3_soft_heap_limit64(N) except that memory allocations will fail
                   6884: ** when the hard heap limit is reached.
                   6885: **
                   6886: ** ^The return value from both sqlite3_soft_heap_limit64() and
                   6887: ** sqlite3_hard_heap_limit64() is the size of
                   6888: ** the heap limit prior to the call, or negative in the case of an
1.2       misho    6889: ** error.  ^If the argument N is negative
1.5       misho    6890: ** then no change is made to the heap limit.  Hence, the current
                   6891: ** size of heap limits can be determined by invoking
                   6892: ** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1).
                   6893: **
                   6894: ** ^Setting the heap limits to zero disables the heap limiter mechanism.
                   6895: **
                   6896: ** ^The soft heap limit may not be greater than the hard heap limit.
                   6897: ** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N)
                   6898: ** is invoked with a value of N that is greater than the hard heap limit,
1.6.2.1 ! misho    6899: ** the soft heap limit is set to the value of the hard heap limit.
1.5       misho    6900: ** ^The soft heap limit is automatically enabled whenever the hard heap
                   6901: ** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and
                   6902: ** the soft heap limit is outside the range of 1..N, then the soft heap
                   6903: ** limit is set to N.  ^Invoking sqlite3_soft_heap_limit64(0) when the
                   6904: ** hard heap limit is enabled makes the soft heap limit equal to the
                   6905: ** hard heap limit.
1.2       misho    6906: **
1.5       misho    6907: ** The memory allocation limits can also be adjusted using
                   6908: ** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit].
1.2       misho    6909: **
1.5       misho    6910: ** ^(The heap limits are not enforced in the current implementation
1.2       misho    6911: ** if one or more of following conditions are true:
                   6912: **
                   6913: ** <ul>
1.5       misho    6914: ** <li> The limit value is set to zero.
1.2       misho    6915: ** <li> Memory accounting is disabled using a combination of the
                   6916: **      [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
                   6917: **      the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
                   6918: ** <li> An alternative page cache implementation is specified using
                   6919: **      [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
                   6920: ** <li> The page cache allocates from its own memory pool supplied
                   6921: **      by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
                   6922: **      from the heap.
                   6923: ** </ul>)^
                   6924: **
1.5       misho    6925: ** The circumstances under which SQLite will enforce the heap limits may
1.2       misho    6926: ** changes in future releases of SQLite.
                   6927: */
                   6928: SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
1.5       misho    6929: SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N);
1.2       misho    6930: 
                   6931: /*
                   6932: ** CAPI3REF: Deprecated Soft Heap Limit Interface
                   6933: ** DEPRECATED
                   6934: **
                   6935: ** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
                   6936: ** interface.  This routine is provided for historical compatibility
                   6937: ** only.  All new applications should use the
                   6938: ** [sqlite3_soft_heap_limit64()] interface rather than this one.
                   6939: */
                   6940: SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
                   6941: 
                   6942: 
                   6943: /*
                   6944: ** CAPI3REF: Extract Metadata About A Column Of A Table
1.4       misho    6945: ** METHOD: sqlite3
1.2       misho    6946: **
1.4       misho    6947: ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns
                   6948: ** information about column C of table T in database D
                   6949: ** on [database connection] X.)^  ^The sqlite3_table_column_metadata()
                   6950: ** interface returns SQLITE_OK and fills in the non-NULL pointers in
                   6951: ** the final five arguments with appropriate values if the specified
                   6952: ** column exists.  ^The sqlite3_table_column_metadata() interface returns
1.5       misho    6953: ** SQLITE_ERROR if the specified column does not exist.
1.4       misho    6954: ** ^If the column-name parameter to sqlite3_table_column_metadata() is a
                   6955: ** NULL pointer, then this routine simply checks for the existence of the
                   6956: ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it
1.5       misho    6957: ** does not.  If the table name parameter T in a call to
                   6958: ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is
                   6959: ** undefined behavior.
1.2       misho    6960: **
                   6961: ** ^The column is identified by the second, third and fourth parameters to
1.4       misho    6962: ** this function. ^(The second parameter is either the name of the database
1.2       misho    6963: ** (i.e. "main", "temp", or an attached database) containing the specified
1.4       misho    6964: ** table or NULL.)^ ^If it is NULL, then all attached databases are searched
1.2       misho    6965: ** for the table using the same algorithm used by the database engine to
                   6966: ** resolve unqualified table references.
                   6967: **
                   6968: ** ^The third and fourth parameters to this function are the table and column
1.4       misho    6969: ** name of the desired column, respectively.
1.2       misho    6970: **
                   6971: ** ^Metadata is returned by writing to the memory locations passed as the 5th
                   6972: ** and subsequent parameters to this function. ^Any of these arguments may be
                   6973: ** NULL, in which case the corresponding element of metadata is omitted.
                   6974: **
                   6975: ** ^(<blockquote>
                   6976: ** <table border="1">
                   6977: ** <tr><th> Parameter <th> Output<br>Type <th>  Description
                   6978: **
                   6979: ** <tr><td> 5th <td> const char* <td> Data type
                   6980: ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
                   6981: ** <tr><td> 7th <td> int         <td> True if column has a NOT NULL constraint
                   6982: ** <tr><td> 8th <td> int         <td> True if column is part of the PRIMARY KEY
                   6983: ** <tr><td> 9th <td> int         <td> True if column is [AUTOINCREMENT]
                   6984: ** </table>
                   6985: ** </blockquote>)^
                   6986: **
                   6987: ** ^The memory pointed to by the character pointers returned for the
1.4       misho    6988: ** declaration type and collation sequence is valid until the next
1.2       misho    6989: ** call to any SQLite API function.
                   6990: **
                   6991: ** ^If the specified table is actually a view, an [error code] is returned.
                   6992: **
1.5       misho    6993: ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table
1.4       misho    6994: ** is not a [WITHOUT ROWID] table and an
1.2       misho    6995: ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
                   6996: ** parameters are set for the explicitly declared column. ^(If there is no
1.4       misho    6997: ** [INTEGER PRIMARY KEY] column, then the outputs
                   6998: ** for the [rowid] are set as follows:
1.2       misho    6999: **
                   7000: ** <pre>
                   7001: **     data type: "INTEGER"
                   7002: **     collation sequence: "BINARY"
                   7003: **     not null: 0
                   7004: **     primary key: 1
                   7005: **     auto increment: 0
                   7006: ** </pre>)^
                   7007: **
1.4       misho    7008: ** ^This function causes all database schemas to be read from disk and
                   7009: ** parsed, if that has not already been done, and returns an error if
                   7010: ** any errors are encountered while loading the schema.
1.2       misho    7011: */
                   7012: SQLITE_API int sqlite3_table_column_metadata(
                   7013:   sqlite3 *db,                /* Connection handle */
                   7014:   const char *zDbName,        /* Database name or NULL */
                   7015:   const char *zTableName,     /* Table name */
                   7016:   const char *zColumnName,    /* Column name */
                   7017:   char const **pzDataType,    /* OUTPUT: Declared data type */
                   7018:   char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
                   7019:   int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
                   7020:   int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
                   7021:   int *pAutoinc               /* OUTPUT: True if column is auto-increment */
                   7022: );
                   7023: 
                   7024: /*
                   7025: ** CAPI3REF: Load An Extension
1.4       misho    7026: ** METHOD: sqlite3
1.2       misho    7027: **
                   7028: ** ^This interface loads an SQLite extension library from the named file.
                   7029: **
                   7030: ** ^The sqlite3_load_extension() interface attempts to load an
1.4       misho    7031: ** [SQLite extension] library contained in the file zFile.  If
                   7032: ** the file cannot be loaded directly, attempts are made to load
                   7033: ** with various operating-system specific extensions added.
                   7034: ** So for example, if "samplelib" cannot be loaded, then names like
                   7035: ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
                   7036: ** be tried also.
1.2       misho    7037: **
                   7038: ** ^The entry point is zProc.
1.4       misho    7039: ** ^(zProc may be 0, in which case SQLite will try to come up with an
                   7040: ** entry point name on its own.  It first tries "sqlite3_extension_init".
                   7041: ** If that does not work, it constructs a name "sqlite3_X_init" where the
                   7042: ** X is consists of the lower-case equivalent of all ASCII alphabetic
                   7043: ** characters in the filename from the last "/" to the first following
                   7044: ** "." and omitting any initial "lib".)^
1.2       misho    7045: ** ^The sqlite3_load_extension() interface returns
                   7046: ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
                   7047: ** ^If an error occurs and pzErrMsg is not 0, then the
                   7048: ** [sqlite3_load_extension()] interface shall attempt to
                   7049: ** fill *pzErrMsg with error message text stored in memory
                   7050: ** obtained from [sqlite3_malloc()]. The calling function
                   7051: ** should free this memory by calling [sqlite3_free()].
                   7052: **
                   7053: ** ^Extension loading must be enabled using
1.4       misho    7054: ** [sqlite3_enable_load_extension()] or
                   7055: ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)
                   7056: ** prior to calling this API,
1.2       misho    7057: ** otherwise an error will be returned.
                   7058: **
1.5       misho    7059: ** <b>Security warning:</b> It is recommended that the
1.4       misho    7060: ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this
                   7061: ** interface.  The use of the [sqlite3_enable_load_extension()] interface
                   7062: ** should be avoided.  This will keep the SQL function [load_extension()]
                   7063: ** disabled and prevent SQL injections from giving attackers
                   7064: ** access to extension loading capabilities.
                   7065: **
1.2       misho    7066: ** See also the [load_extension() SQL function].
                   7067: */
                   7068: SQLITE_API int sqlite3_load_extension(
                   7069:   sqlite3 *db,          /* Load the extension into this database connection */
                   7070:   const char *zFile,    /* Name of the shared library containing extension */
                   7071:   const char *zProc,    /* Entry point.  Derived from zFile if 0 */
                   7072:   char **pzErrMsg       /* Put error message here if not 0 */
                   7073: );
                   7074: 
                   7075: /*
                   7076: ** CAPI3REF: Enable Or Disable Extension Loading
1.4       misho    7077: ** METHOD: sqlite3
1.2       misho    7078: **
                   7079: ** ^So as not to open security holes in older applications that are
1.4       misho    7080: ** unprepared to deal with [extension loading], and as a means of disabling
                   7081: ** [extension loading] while evaluating user-entered SQL, the following API
1.2       misho    7082: ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
                   7083: **
1.4       misho    7084: ** ^Extension loading is off by default.
1.2       misho    7085: ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
                   7086: ** to turn extension loading on and call it with onoff==0 to turn
                   7087: ** it back off again.
1.4       misho    7088: **
                   7089: ** ^This interface enables or disables both the C-API
                   7090: ** [sqlite3_load_extension()] and the SQL function [load_extension()].
                   7091: ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)
                   7092: ** to enable or disable only the C-API.)^
                   7093: **
                   7094: ** <b>Security warning:</b> It is recommended that extension loading
1.5       misho    7095: ** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method
1.4       misho    7096: ** rather than this interface, so the [load_extension()] SQL function
                   7097: ** remains disabled. This will prevent SQL injections from giving attackers
                   7098: ** access to extension loading capabilities.
1.2       misho    7099: */
                   7100: SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
                   7101: 
                   7102: /*
                   7103: ** CAPI3REF: Automatically Load Statically Linked Extensions
                   7104: **
                   7105: ** ^This interface causes the xEntryPoint() function to be invoked for
                   7106: ** each new [database connection] that is created.  The idea here is that
1.4       misho    7107: ** xEntryPoint() is the entry point for a statically linked [SQLite extension]
1.2       misho    7108: ** that is to be automatically loaded into all new database connections.
                   7109: **
                   7110: ** ^(Even though the function prototype shows that xEntryPoint() takes
                   7111: ** no arguments and returns void, SQLite invokes xEntryPoint() with three
1.4       misho    7112: ** arguments and expects an integer result as if the signature of the
1.2       misho    7113: ** entry point where as follows:
                   7114: **
                   7115: ** <blockquote><pre>
                   7116: ** &nbsp;  int xEntryPoint(
                   7117: ** &nbsp;    sqlite3 *db,
                   7118: ** &nbsp;    const char **pzErrMsg,
                   7119: ** &nbsp;    const struct sqlite3_api_routines *pThunk
                   7120: ** &nbsp;  );
                   7121: ** </pre></blockquote>)^
                   7122: **
                   7123: ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
                   7124: ** point to an appropriate error message (obtained from [sqlite3_mprintf()])
                   7125: ** and return an appropriate [error code].  ^SQLite ensures that *pzErrMsg
                   7126: ** is NULL before calling the xEntryPoint().  ^SQLite will invoke
                   7127: ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns.  ^If any
                   7128: ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
                   7129: ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
                   7130: **
                   7131: ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
                   7132: ** on the list of automatic extensions is a harmless no-op. ^No entry point
                   7133: ** will be called more than once for each database connection that is opened.
                   7134: **
1.4       misho    7135: ** See also: [sqlite3_reset_auto_extension()]
                   7136: ** and [sqlite3_cancel_auto_extension()]
1.2       misho    7137: */
1.4       misho    7138: SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void));
                   7139: 
                   7140: /*
                   7141: ** CAPI3REF: Cancel Automatic Extension Loading
                   7142: **
                   7143: ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
                   7144: ** initialization routine X that was registered using a prior call to
                   7145: ** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
1.5       misho    7146: ** routine returns 1 if initialization routine X was successfully
1.4       misho    7147: ** unregistered and it returns 0 if X was not on the list of initialization
                   7148: ** routines.
                   7149: */
                   7150: SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void));
1.2       misho    7151: 
                   7152: /*
                   7153: ** CAPI3REF: Reset Automatic Extension Loading
                   7154: **
                   7155: ** ^This interface disables all automatic extensions previously
                   7156: ** registered using [sqlite3_auto_extension()].
                   7157: */
                   7158: SQLITE_API void sqlite3_reset_auto_extension(void);
                   7159: 
                   7160: /*
                   7161: ** Structures used by the virtual table interface
                   7162: */
                   7163: typedef struct sqlite3_vtab sqlite3_vtab;
                   7164: typedef struct sqlite3_index_info sqlite3_index_info;
                   7165: typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
                   7166: typedef struct sqlite3_module sqlite3_module;
                   7167: 
                   7168: /*
                   7169: ** CAPI3REF: Virtual Table Object
                   7170: ** KEYWORDS: sqlite3_module {virtual table module}
                   7171: **
1.5       misho    7172: ** This structure, sometimes called a "virtual table module",
                   7173: ** defines the implementation of a [virtual table].
1.2       misho    7174: ** This structure consists mostly of methods for the module.
                   7175: **
                   7176: ** ^A virtual table module is created by filling in a persistent
                   7177: ** instance of this structure and passing a pointer to that instance
                   7178: ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
                   7179: ** ^The registration remains valid until it is replaced by a different
                   7180: ** module or until the [database connection] closes.  The content
                   7181: ** of this structure must not change while it is registered with
                   7182: ** any database connection.
                   7183: */
                   7184: struct sqlite3_module {
                   7185:   int iVersion;
                   7186:   int (*xCreate)(sqlite3*, void *pAux,
                   7187:                int argc, const char *const*argv,
                   7188:                sqlite3_vtab **ppVTab, char**);
                   7189:   int (*xConnect)(sqlite3*, void *pAux,
                   7190:                int argc, const char *const*argv,
                   7191:                sqlite3_vtab **ppVTab, char**);
                   7192:   int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
                   7193:   int (*xDisconnect)(sqlite3_vtab *pVTab);
                   7194:   int (*xDestroy)(sqlite3_vtab *pVTab);
                   7195:   int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
                   7196:   int (*xClose)(sqlite3_vtab_cursor*);
                   7197:   int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
                   7198:                 int argc, sqlite3_value **argv);
                   7199:   int (*xNext)(sqlite3_vtab_cursor*);
                   7200:   int (*xEof)(sqlite3_vtab_cursor*);
                   7201:   int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
                   7202:   int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
                   7203:   int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
                   7204:   int (*xBegin)(sqlite3_vtab *pVTab);
                   7205:   int (*xSync)(sqlite3_vtab *pVTab);
                   7206:   int (*xCommit)(sqlite3_vtab *pVTab);
                   7207:   int (*xRollback)(sqlite3_vtab *pVTab);
                   7208:   int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
                   7209:                        void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
                   7210:                        void **ppArg);
                   7211:   int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
1.5       misho    7212:   /* The methods above are in version 1 of the sqlite_module object. Those
1.2       misho    7213:   ** below are for version 2 and greater. */
                   7214:   int (*xSavepoint)(sqlite3_vtab *pVTab, int);
                   7215:   int (*xRelease)(sqlite3_vtab *pVTab, int);
                   7216:   int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
1.5       misho    7217:   /* The methods above are in versions 1 and 2 of the sqlite_module object.
                   7218:   ** Those below are for version 3 and greater. */
                   7219:   int (*xShadowName)(const char*);
1.2       misho    7220: };
                   7221: 
                   7222: /*
                   7223: ** CAPI3REF: Virtual Table Indexing Information
                   7224: ** KEYWORDS: sqlite3_index_info
                   7225: **
                   7226: ** The sqlite3_index_info structure and its substructures is used as part
                   7227: ** of the [virtual table] interface to
                   7228: ** pass information into and receive the reply from the [xBestIndex]
                   7229: ** method of a [virtual table module].  The fields under **Inputs** are the
                   7230: ** inputs to xBestIndex and are read-only.  xBestIndex inserts its
                   7231: ** results into the **Outputs** fields.
                   7232: **
                   7233: ** ^(The aConstraint[] array records WHERE clause constraints of the form:
                   7234: **
                   7235: ** <blockquote>column OP expr</blockquote>
                   7236: **
                   7237: ** where OP is =, &lt;, &lt;=, &gt;, or &gt;=.)^  ^(The particular operator is
                   7238: ** stored in aConstraint[].op using one of the
                   7239: ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
                   7240: ** ^(The index of the column is stored in
                   7241: ** aConstraint[].iColumn.)^  ^(aConstraint[].usable is TRUE if the
                   7242: ** expr on the right-hand side can be evaluated (and thus the constraint
                   7243: ** is usable) and false if it cannot.)^
                   7244: **
                   7245: ** ^The optimizer automatically inverts terms of the form "expr OP column"
                   7246: ** and makes other simplifications to the WHERE clause in an attempt to
                   7247: ** get as many WHERE clause terms into the form shown above as possible.
                   7248: ** ^The aConstraint[] array only reports WHERE clause terms that are
                   7249: ** relevant to the particular virtual table being queried.
                   7250: **
                   7251: ** ^Information about the ORDER BY clause is stored in aOrderBy[].
                   7252: ** ^Each term of aOrderBy records a column of the ORDER BY clause.
                   7253: **
1.4       misho    7254: ** The colUsed field indicates which columns of the virtual table may be
                   7255: ** required by the current scan. Virtual table columns are numbered from
                   7256: ** zero in the order in which they appear within the CREATE TABLE statement
                   7257: ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),
                   7258: ** the corresponding bit is set within the colUsed mask if the column may be
                   7259: ** required by SQLite. If the table has at least 64 columns and any column
                   7260: ** to the right of the first 63 is required, then bit 63 of colUsed is also
                   7261: ** set. In other words, column iCol may be required if the expression
1.5       misho    7262: ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to
1.4       misho    7263: ** non-zero.
                   7264: **
1.2       misho    7265: ** The [xBestIndex] method must fill aConstraintUsage[] with information
                   7266: ** about what parameters to pass to xFilter.  ^If argvIndex>0 then
                   7267: ** the right-hand side of the corresponding aConstraint[] is evaluated
                   7268: ** and becomes the argvIndex-th entry in argv.  ^(If aConstraintUsage[].omit
                   7269: ** is true, then the constraint is assumed to be fully handled by the
1.5       misho    7270: ** virtual table and might not be checked again by the byte code.)^ ^(The
                   7271: ** aConstraintUsage[].omit flag is an optimization hint. When the omit flag
                   7272: ** is left in its default setting of false, the constraint will always be
                   7273: ** checked separately in byte code.  If the omit flag is change to true, then
                   7274: ** the constraint may or may not be checked in byte code.  In other words,
                   7275: ** when the omit flag is true there is no guarantee that the constraint will
                   7276: ** not be checked again using byte code.)^
1.2       misho    7277: **
1.6.2.1 ! misho    7278: ** ^The idxNum and idxStr values are recorded and passed into the
1.2       misho    7279: ** [xFilter] method.
1.6.2.1 ! misho    7280: ** ^[sqlite3_free()] is used to free idxStr if and only if
        !          7281: ** needToFreeIdxStr is true.
1.2       misho    7282: **
                   7283: ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
                   7284: ** the correct order to satisfy the ORDER BY clause so that no separate
                   7285: ** sorting step is required.
                   7286: **
1.4       misho    7287: ** ^The estimatedCost value is an estimate of the cost of a particular
                   7288: ** strategy. A cost of N indicates that the cost of the strategy is similar
1.5       misho    7289: ** to a linear scan of an SQLite table with N rows. A cost of log(N)
1.4       misho    7290: ** indicates that the expense of the operation is similar to that of a
                   7291: ** binary search on a unique indexed field of an SQLite table with N rows.
                   7292: **
                   7293: ** ^The estimatedRows value is an estimate of the number of rows that
                   7294: ** will be returned by the strategy.
                   7295: **
1.5       misho    7296: ** The xBestIndex method may optionally populate the idxFlags field with a
1.4       misho    7297: ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -
                   7298: ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite
1.5       misho    7299: ** assumes that the strategy may visit at most one row.
1.4       misho    7300: **
                   7301: ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then
                   7302: ** SQLite also assumes that if a call to the xUpdate() method is made as
                   7303: ** part of the same statement to delete or update a virtual table row and the
                   7304: ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback
                   7305: ** any database changes. In other words, if the xUpdate() returns
                   7306: ** SQLITE_CONSTRAINT, the database contents must be exactly as they were
                   7307: ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not
                   7308: ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by
                   7309: ** the xUpdate method are automatically rolled back by SQLite.
                   7310: **
                   7311: ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info
1.5       misho    7312: ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]).
                   7313: ** If a virtual table extension is
                   7314: ** used with an SQLite version earlier than 3.8.2, the results of attempting
                   7315: ** to read or write the estimatedRows field are undefined (but are likely
                   7316: ** to include crashing the application). The estimatedRows field should
1.4       misho    7317: ** therefore only be used if [sqlite3_libversion_number()] returns a
                   7318: ** value greater than or equal to 3008002. Similarly, the idxFlags field
1.5       misho    7319: ** was added for [version 3.9.0] ([dateof:3.9.0]).
                   7320: ** It may therefore only be used if
1.4       misho    7321: ** sqlite3_libversion_number() returns a value greater than or equal to
                   7322: ** 3009000.
1.2       misho    7323: */
                   7324: struct sqlite3_index_info {
                   7325:   /* Inputs */
                   7326:   int nConstraint;           /* Number of entries in aConstraint */
                   7327:   struct sqlite3_index_constraint {
1.4       misho    7328:      int iColumn;              /* Column constrained.  -1 for ROWID */
1.2       misho    7329:      unsigned char op;         /* Constraint operator */
                   7330:      unsigned char usable;     /* True if this constraint is usable */
                   7331:      int iTermOffset;          /* Used internally - xBestIndex should ignore */
                   7332:   } *aConstraint;            /* Table of WHERE clause constraints */
                   7333:   int nOrderBy;              /* Number of terms in the ORDER BY clause */
                   7334:   struct sqlite3_index_orderby {
                   7335:      int iColumn;              /* Column number */
                   7336:      unsigned char desc;       /* True for DESC.  False for ASC. */
                   7337:   } *aOrderBy;               /* The ORDER BY clause */
                   7338:   /* Outputs */
                   7339:   struct sqlite3_index_constraint_usage {
                   7340:     int argvIndex;           /* if >0, constraint is part of argv to xFilter */
                   7341:     unsigned char omit;      /* Do not code a test for this constraint */
                   7342:   } *aConstraintUsage;
                   7343:   int idxNum;                /* Number used to identify the index */
                   7344:   char *idxStr;              /* String, possibly obtained from sqlite3_malloc */
                   7345:   int needToFreeIdxStr;      /* Free idxStr using sqlite3_free() if true */
                   7346:   int orderByConsumed;       /* True if output is already ordered */
1.4       misho    7347:   double estimatedCost;           /* Estimated cost of using this index */
                   7348:   /* Fields below are only available in SQLite 3.8.2 and later */
                   7349:   sqlite3_int64 estimatedRows;    /* Estimated number of rows returned */
                   7350:   /* Fields below are only available in SQLite 3.9.0 and later */
                   7351:   int idxFlags;              /* Mask of SQLITE_INDEX_SCAN_* flags */
                   7352:   /* Fields below are only available in SQLite 3.10.0 and later */
                   7353:   sqlite3_uint64 colUsed;    /* Input: Mask of columns used by statement */
1.2       misho    7354: };
                   7355: 
                   7356: /*
1.4       misho    7357: ** CAPI3REF: Virtual Table Scan Flags
1.5       misho    7358: **
                   7359: ** Virtual table implementations are allowed to set the
                   7360: ** [sqlite3_index_info].idxFlags field to some combination of
                   7361: ** these bits.
1.4       misho    7362: */
                   7363: #define SQLITE_INDEX_SCAN_UNIQUE      1     /* Scan visits at most 1 row */
                   7364: 
                   7365: /*
1.2       misho    7366: ** CAPI3REF: Virtual Table Constraint Operator Codes
                   7367: **
1.5       misho    7368: ** These macros define the allowed values for the
1.2       misho    7369: ** [sqlite3_index_info].aConstraint[].op field.  Each value represents
1.6.2.1 ! misho    7370: ** an operator that is part of a constraint term in the WHERE clause of
1.2       misho    7371: ** a query that uses a [virtual table].
1.6.2.1 ! misho    7372: **
        !          7373: ** ^The left-hand operand of the operator is given by the corresponding
        !          7374: ** aConstraint[].iColumn field.  ^An iColumn of -1 indicates the left-hand
        !          7375: ** operand is the rowid.
        !          7376: ** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET
        !          7377: ** operators have no left-hand operand, and so for those operators the
        !          7378: ** corresponding aConstraint[].iColumn is meaningless and should not be
        !          7379: ** used.
        !          7380: **
        !          7381: ** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through
        !          7382: ** value 255 are reserved to represent functions that are overloaded
        !          7383: ** by the [xFindFunction|xFindFunction method] of the virtual table
        !          7384: ** implementation.
        !          7385: **
        !          7386: ** The right-hand operands for each constraint might be accessible using
        !          7387: ** the [sqlite3_vtab_rhs_value()] interface.  Usually the right-hand
        !          7388: ** operand is only available if it appears as a single constant literal
        !          7389: ** in the input SQL.  If the right-hand operand is another column or an
        !          7390: ** expression (even a constant expression) or a parameter, then the
        !          7391: ** sqlite3_vtab_rhs_value() probably will not be able to extract it.
        !          7392: ** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and
        !          7393: ** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand
        !          7394: ** and hence calls to sqlite3_vtab_rhs_value() for those operators will
        !          7395: ** always return SQLITE_NOTFOUND.
        !          7396: **
        !          7397: ** The collating sequence to be used for comparison can be found using
        !          7398: ** the [sqlite3_vtab_collation()] interface.  For most real-world virtual
        !          7399: ** tables, the collating sequence of constraints does not matter (for example
        !          7400: ** because the constraints are numeric) and so the sqlite3_vtab_collation()
        !          7401: ** interface is not commonly needed.
        !          7402: */
        !          7403: #define SQLITE_INDEX_CONSTRAINT_EQ          2
        !          7404: #define SQLITE_INDEX_CONSTRAINT_GT          4
        !          7405: #define SQLITE_INDEX_CONSTRAINT_LE          8
        !          7406: #define SQLITE_INDEX_CONSTRAINT_LT         16
        !          7407: #define SQLITE_INDEX_CONSTRAINT_GE         32
        !          7408: #define SQLITE_INDEX_CONSTRAINT_MATCH      64
        !          7409: #define SQLITE_INDEX_CONSTRAINT_LIKE       65
        !          7410: #define SQLITE_INDEX_CONSTRAINT_GLOB       66
        !          7411: #define SQLITE_INDEX_CONSTRAINT_REGEXP     67
        !          7412: #define SQLITE_INDEX_CONSTRAINT_NE         68
        !          7413: #define SQLITE_INDEX_CONSTRAINT_ISNOT      69
        !          7414: #define SQLITE_INDEX_CONSTRAINT_ISNOTNULL  70
        !          7415: #define SQLITE_INDEX_CONSTRAINT_ISNULL     71
        !          7416: #define SQLITE_INDEX_CONSTRAINT_IS         72
        !          7417: #define SQLITE_INDEX_CONSTRAINT_LIMIT      73
        !          7418: #define SQLITE_INDEX_CONSTRAINT_OFFSET     74
        !          7419: #define SQLITE_INDEX_CONSTRAINT_FUNCTION  150
1.2       misho    7420: 
                   7421: /*
                   7422: ** CAPI3REF: Register A Virtual Table Implementation
1.4       misho    7423: ** METHOD: sqlite3
1.2       misho    7424: **
                   7425: ** ^These routines are used to register a new [virtual table module] name.
                   7426: ** ^Module names must be registered before
                   7427: ** creating a new [virtual table] using the module and before using a
                   7428: ** preexisting [virtual table] for the module.
                   7429: **
                   7430: ** ^The module name is registered on the [database connection] specified
1.5       misho    7431: ** by the first parameter.  ^The name of the module is given by the
1.2       misho    7432: ** second parameter.  ^The third parameter is a pointer to
                   7433: ** the implementation of the [virtual table module].   ^The fourth
                   7434: ** parameter is an arbitrary client data pointer that is passed through
                   7435: ** into the [xCreate] and [xConnect] methods of the virtual table module
                   7436: ** when a new virtual table is be being created or reinitialized.
                   7437: **
                   7438: ** ^The sqlite3_create_module_v2() interface has a fifth parameter which
                   7439: ** is a pointer to a destructor for the pClientData.  ^SQLite will
                   7440: ** invoke the destructor function (if it is not NULL) when SQLite
                   7441: ** no longer needs the pClientData pointer.  ^The destructor will also
                   7442: ** be invoked if the call to sqlite3_create_module_v2() fails.
                   7443: ** ^The sqlite3_create_module()
                   7444: ** interface is equivalent to sqlite3_create_module_v2() with a NULL
                   7445: ** destructor.
1.5       misho    7446: **
                   7447: ** ^If the third parameter (the pointer to the sqlite3_module object) is
1.6.2.1 ! misho    7448: ** NULL then no new module is created and any existing modules with the
1.5       misho    7449: ** same name are dropped.
                   7450: **
                   7451: ** See also: [sqlite3_drop_modules()]
1.2       misho    7452: */
                   7453: SQLITE_API int sqlite3_create_module(
                   7454:   sqlite3 *db,               /* SQLite connection to register module with */
                   7455:   const char *zName,         /* Name of the module */
                   7456:   const sqlite3_module *p,   /* Methods for the module */
                   7457:   void *pClientData          /* Client data for xCreate/xConnect */
                   7458: );
                   7459: SQLITE_API int sqlite3_create_module_v2(
                   7460:   sqlite3 *db,               /* SQLite connection to register module with */
                   7461:   const char *zName,         /* Name of the module */
                   7462:   const sqlite3_module *p,   /* Methods for the module */
                   7463:   void *pClientData,         /* Client data for xCreate/xConnect */
                   7464:   void(*xDestroy)(void*)     /* Module destructor function */
                   7465: );
                   7466: 
                   7467: /*
1.5       misho    7468: ** CAPI3REF: Remove Unnecessary Virtual Table Implementations
                   7469: ** METHOD: sqlite3
                   7470: **
                   7471: ** ^The sqlite3_drop_modules(D,L) interface removes all virtual
                   7472: ** table modules from database connection D except those named on list L.
                   7473: ** The L parameter must be either NULL or a pointer to an array of pointers
                   7474: ** to strings where the array is terminated by a single NULL pointer.
                   7475: ** ^If the L parameter is NULL, then all virtual table modules are removed.
                   7476: **
                   7477: ** See also: [sqlite3_create_module()]
                   7478: */
                   7479: SQLITE_API int sqlite3_drop_modules(
                   7480:   sqlite3 *db,                /* Remove modules from this connection */
                   7481:   const char **azKeep         /* Except, do not remove the ones named here */
                   7482: );
                   7483: 
                   7484: /*
1.2       misho    7485: ** CAPI3REF: Virtual Table Instance Object
                   7486: ** KEYWORDS: sqlite3_vtab
                   7487: **
                   7488: ** Every [virtual table module] implementation uses a subclass
                   7489: ** of this object to describe a particular instance
                   7490: ** of the [virtual table].  Each subclass will
                   7491: ** be tailored to the specific needs of the module implementation.
                   7492: ** The purpose of this superclass is to define certain fields that are
                   7493: ** common to all module implementations.
                   7494: **
                   7495: ** ^Virtual tables methods can set an error message by assigning a
                   7496: ** string obtained from [sqlite3_mprintf()] to zErrMsg.  The method should
                   7497: ** take care that any prior string is freed by a call to [sqlite3_free()]
                   7498: ** prior to assigning a new string to zErrMsg.  ^After the error message
                   7499: ** is delivered up to the client application, the string will be automatically
                   7500: ** freed by sqlite3_free() and the zErrMsg field will be zeroed.
                   7501: */
                   7502: struct sqlite3_vtab {
                   7503:   const sqlite3_module *pModule;  /* The module for this virtual table */
1.4       misho    7504:   int nRef;                       /* Number of open cursors */
1.2       misho    7505:   char *zErrMsg;                  /* Error message from sqlite3_mprintf() */
                   7506:   /* Virtual table implementations will typically add additional fields */
                   7507: };
                   7508: 
                   7509: /*
                   7510: ** CAPI3REF: Virtual Table Cursor Object
                   7511: ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
                   7512: **
                   7513: ** Every [virtual table module] implementation uses a subclass of the
                   7514: ** following structure to describe cursors that point into the
                   7515: ** [virtual table] and are used
                   7516: ** to loop through the virtual table.  Cursors are created using the
                   7517: ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
                   7518: ** by the [sqlite3_module.xClose | xClose] method.  Cursors are used
                   7519: ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
                   7520: ** of the module.  Each module implementation will define
                   7521: ** the content of a cursor structure to suit its own needs.
                   7522: **
                   7523: ** This superclass exists in order to define fields of the cursor that
                   7524: ** are common to all implementations.
                   7525: */
                   7526: struct sqlite3_vtab_cursor {
                   7527:   sqlite3_vtab *pVtab;      /* Virtual table of this cursor */
                   7528:   /* Virtual table implementations will typically add additional fields */
                   7529: };
                   7530: 
                   7531: /*
                   7532: ** CAPI3REF: Declare The Schema Of A Virtual Table
                   7533: **
                   7534: ** ^The [xCreate] and [xConnect] methods of a
                   7535: ** [virtual table module] call this interface
                   7536: ** to declare the format (the names and datatypes of the columns) of
                   7537: ** the virtual tables they implement.
                   7538: */
                   7539: SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
                   7540: 
                   7541: /*
                   7542: ** CAPI3REF: Overload A Function For A Virtual Table
1.4       misho    7543: ** METHOD: sqlite3
1.2       misho    7544: **
                   7545: ** ^(Virtual tables can provide alternative implementations of functions
1.5       misho    7546: ** using the [xFindFunction] method of the [virtual table module].
1.2       misho    7547: ** But global versions of those functions
                   7548: ** must exist in order to be overloaded.)^
                   7549: **
                   7550: ** ^(This API makes sure a global version of a function with a particular
                   7551: ** name and number of parameters exists.  If no such function exists
                   7552: ** before this API is called, a new function is created.)^  ^The implementation
                   7553: ** of the new function always causes an exception to be thrown.  So
                   7554: ** the new function is not good for anything by itself.  Its only
                   7555: ** purpose is to be a placeholder function that can be overloaded
                   7556: ** by a [virtual table].
                   7557: */
                   7558: SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
                   7559: 
                   7560: /*
                   7561: ** CAPI3REF: A Handle To An Open BLOB
                   7562: ** KEYWORDS: {BLOB handle} {BLOB handles}
                   7563: **
                   7564: ** An instance of this object represents an open BLOB on which
                   7565: ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
                   7566: ** ^Objects of this type are created by [sqlite3_blob_open()]
                   7567: ** and destroyed by [sqlite3_blob_close()].
                   7568: ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
                   7569: ** can be used to read or write small subsections of the BLOB.
                   7570: ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
                   7571: */
                   7572: typedef struct sqlite3_blob sqlite3_blob;
                   7573: 
                   7574: /*
                   7575: ** CAPI3REF: Open A BLOB For Incremental I/O
1.4       misho    7576: ** METHOD: sqlite3
                   7577: ** CONSTRUCTOR: sqlite3_blob
1.2       misho    7578: **
                   7579: ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
                   7580: ** in row iRow, column zColumn, table zTable in database zDb;
                   7581: ** in other words, the same BLOB that would be selected by:
                   7582: **
                   7583: ** <pre>
                   7584: **     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
                   7585: ** </pre>)^
                   7586: **
1.5       misho    7587: ** ^(Parameter zDb is not the filename that contains the database, but
1.4       misho    7588: ** rather the symbolic name of the database. For attached databases, this is
                   7589: ** the name that appears after the AS keyword in the [ATTACH] statement.
                   7590: ** For the main database file, the database name is "main". For TEMP
                   7591: ** tables, the database name is "temp".)^
                   7592: **
1.2       misho    7593: ** ^If the flags parameter is non-zero, then the BLOB is opened for read
1.4       misho    7594: ** and write access. ^If the flags parameter is zero, the BLOB is opened for
                   7595: ** read-only access.
                   7596: **
                   7597: ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored
                   7598: ** in *ppBlob. Otherwise an [error code] is returned and, unless the error
                   7599: ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided
1.5       misho    7600: ** the API is not misused, it is always safe to call [sqlite3_blob_close()]
1.4       misho    7601: ** on *ppBlob after this function it returns.
                   7602: **
                   7603: ** This function fails with SQLITE_ERROR if any of the following are true:
                   7604: ** <ul>
1.5       misho    7605: **   <li> ^(Database zDb does not exist)^,
                   7606: **   <li> ^(Table zTable does not exist within database zDb)^,
                   7607: **   <li> ^(Table zTable is a WITHOUT ROWID table)^,
1.4       misho    7608: **   <li> ^(Column zColumn does not exist)^,
                   7609: **   <li> ^(Row iRow is not present in the table)^,
                   7610: **   <li> ^(The specified column of row iRow contains a value that is not
                   7611: **         a TEXT or BLOB value)^,
1.5       misho    7612: **   <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE
1.4       misho    7613: **         constraint and the blob is being opened for read/write access)^,
1.5       misho    7614: **   <li> ^([foreign key constraints | Foreign key constraints] are enabled,
1.4       misho    7615: **         column zColumn is part of a [child key] definition and the blob is
                   7616: **         being opened for read/write access)^.
                   7617: ** </ul>
                   7618: **
1.5       misho    7619: ** ^Unless it returns SQLITE_MISUSE, this function sets the
                   7620: ** [database connection] error code and message accessible via
                   7621: ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
                   7622: **
                   7623: ** A BLOB referenced by sqlite3_blob_open() may be read using the
                   7624: ** [sqlite3_blob_read()] interface and modified by using
                   7625: ** [sqlite3_blob_write()].  The [BLOB handle] can be moved to a
                   7626: ** different row of the same table using the [sqlite3_blob_reopen()]
                   7627: ** interface.  However, the column, table, or database of a [BLOB handle]
                   7628: ** cannot be changed after the [BLOB handle] is opened.
1.2       misho    7629: **
                   7630: ** ^(If the row that a BLOB handle points to is modified by an
                   7631: ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
                   7632: ** then the BLOB handle is marked as "expired".
                   7633: ** This is true if any column of the row is changed, even a column
                   7634: ** other than the one the BLOB handle is open on.)^
                   7635: ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
                   7636: ** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
                   7637: ** ^(Changes written into a BLOB prior to the BLOB expiring are not
                   7638: ** rolled back by the expiration of the BLOB.  Such changes will eventually
                   7639: ** commit if the transaction continues to completion.)^
                   7640: **
                   7641: ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
                   7642: ** the opened blob.  ^The size of a blob may not be changed by this
                   7643: ** interface.  Use the [UPDATE] SQL command to change the size of a
                   7644: ** blob.
                   7645: **
                   7646: ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
1.5       misho    7647: ** and the built-in [zeroblob] SQL function may be used to create a
1.4       misho    7648: ** zero-filled blob to read or write using the incremental-blob interface.
1.2       misho    7649: **
                   7650: ** To avoid a resource leak, every open [BLOB handle] should eventually
                   7651: ** be released by a call to [sqlite3_blob_close()].
1.5       misho    7652: **
                   7653: ** See also: [sqlite3_blob_close()],
                   7654: ** [sqlite3_blob_reopen()], [sqlite3_blob_read()],
                   7655: ** [sqlite3_blob_bytes()], [sqlite3_blob_write()].
1.2       misho    7656: */
                   7657: SQLITE_API int sqlite3_blob_open(
                   7658:   sqlite3*,
                   7659:   const char *zDb,
                   7660:   const char *zTable,
                   7661:   const char *zColumn,
                   7662:   sqlite3_int64 iRow,
                   7663:   int flags,
                   7664:   sqlite3_blob **ppBlob
                   7665: );
                   7666: 
                   7667: /*
                   7668: ** CAPI3REF: Move a BLOB Handle to a New Row
1.4       misho    7669: ** METHOD: sqlite3_blob
1.2       misho    7670: **
1.5       misho    7671: ** ^This function is used to move an existing [BLOB handle] so that it points
1.2       misho    7672: ** to a different row of the same database table. ^The new row is identified
                   7673: ** by the rowid value passed as the second argument. Only the row can be
                   7674: ** changed. ^The database, table and column on which the blob handle is open
1.5       misho    7675: ** remain the same. Moving an existing [BLOB handle] to a new row is
1.2       misho    7676: ** faster than closing the existing handle and opening a new one.
                   7677: **
                   7678: ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
                   7679: ** it must exist and there must be either a blob or text value stored in
                   7680: ** the nominated column.)^ ^If the new row is not present in the table, or if
                   7681: ** it does not contain a blob or text value, or if another error occurs, an
                   7682: ** SQLite error code is returned and the blob handle is considered aborted.
                   7683: ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
                   7684: ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
                   7685: ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
                   7686: ** always returns zero.
                   7687: **
                   7688: ** ^This function sets the database handle error code and message.
                   7689: */
1.4       misho    7690: SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
1.2       misho    7691: 
                   7692: /*
                   7693: ** CAPI3REF: Close A BLOB Handle
1.4       misho    7694: ** DESTRUCTOR: sqlite3_blob
1.2       misho    7695: **
1.4       misho    7696: ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed
1.5       misho    7697: ** unconditionally.  Even if this routine returns an error code, the
1.4       misho    7698: ** handle is still closed.)^
                   7699: **
                   7700: ** ^If the blob handle being closed was opened for read-write access, and if
                   7701: ** the database is in auto-commit mode and there are no other open read-write
                   7702: ** blob handles or active write statements, the current transaction is
                   7703: ** committed. ^If an error occurs while committing the transaction, an error
                   7704: ** code is returned and the transaction rolled back.
                   7705: **
                   7706: ** Calling this function with an argument that is not a NULL pointer or an
1.5       misho    7707: ** open blob handle results in undefined behaviour. ^Calling this routine
                   7708: ** with a null pointer (such as would be returned by a failed call to
1.4       misho    7709: ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function
1.5       misho    7710: ** is passed a valid open blob handle, the values returned by the
1.4       misho    7711: ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.
1.2       misho    7712: */
                   7713: SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
                   7714: 
                   7715: /*
                   7716: ** CAPI3REF: Return The Size Of An Open BLOB
1.4       misho    7717: ** METHOD: sqlite3_blob
1.2       misho    7718: **
1.5       misho    7719: ** ^Returns the size in bytes of the BLOB accessible via the
1.2       misho    7720: ** successfully opened [BLOB handle] in its only argument.  ^The
                   7721: ** incremental blob I/O routines can only read or overwriting existing
                   7722: ** blob content; they cannot change the size of a blob.
                   7723: **
                   7724: ** This routine only works on a [BLOB handle] which has been created
                   7725: ** by a prior successful call to [sqlite3_blob_open()] and which has not
                   7726: ** been closed by [sqlite3_blob_close()].  Passing any other pointer in
                   7727: ** to this routine results in undefined and probably undesirable behavior.
                   7728: */
                   7729: SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
                   7730: 
                   7731: /*
                   7732: ** CAPI3REF: Read Data From A BLOB Incrementally
1.4       misho    7733: ** METHOD: sqlite3_blob
1.2       misho    7734: **
                   7735: ** ^(This function is used to read data from an open [BLOB handle] into a
                   7736: ** caller-supplied buffer. N bytes of data are copied into buffer Z
                   7737: ** from the open BLOB, starting at offset iOffset.)^
                   7738: **
                   7739: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
                   7740: ** [SQLITE_ERROR] is returned and no data is read.  ^If N or iOffset is
                   7741: ** less than zero, [SQLITE_ERROR] is returned and no data is read.
                   7742: ** ^The size of the blob (and hence the maximum value of N+iOffset)
                   7743: ** can be determined using the [sqlite3_blob_bytes()] interface.
                   7744: **
                   7745: ** ^An attempt to read from an expired [BLOB handle] fails with an
                   7746: ** error code of [SQLITE_ABORT].
                   7747: **
                   7748: ** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
                   7749: ** Otherwise, an [error code] or an [extended error code] is returned.)^
                   7750: **
                   7751: ** This routine only works on a [BLOB handle] which has been created
                   7752: ** by a prior successful call to [sqlite3_blob_open()] and which has not
                   7753: ** been closed by [sqlite3_blob_close()].  Passing any other pointer in
                   7754: ** to this routine results in undefined and probably undesirable behavior.
                   7755: **
                   7756: ** See also: [sqlite3_blob_write()].
                   7757: */
                   7758: SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
                   7759: 
                   7760: /*
                   7761: ** CAPI3REF: Write Data Into A BLOB Incrementally
1.4       misho    7762: ** METHOD: sqlite3_blob
1.2       misho    7763: **
1.4       misho    7764: ** ^(This function is used to write data into an open [BLOB handle] from a
                   7765: ** caller-supplied buffer. N bytes of data are copied from the buffer Z
                   7766: ** into the open BLOB, starting at offset iOffset.)^
                   7767: **
                   7768: ** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
                   7769: ** Otherwise, an  [error code] or an [extended error code] is returned.)^
1.5       misho    7770: ** ^Unless SQLITE_MISUSE is returned, this function sets the
                   7771: ** [database connection] error code and message accessible via
                   7772: ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions.
1.2       misho    7773: **
                   7774: ** ^If the [BLOB handle] passed as the first argument was not opened for
                   7775: ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
                   7776: ** this function returns [SQLITE_READONLY].
                   7777: **
1.4       misho    7778: ** This function may only modify the contents of the BLOB; it is
1.2       misho    7779: ** not possible to increase the size of a BLOB using this API.
                   7780: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
1.5       misho    7781: ** [SQLITE_ERROR] is returned and no data is written. The size of the
                   7782: ** BLOB (and hence the maximum value of N+iOffset) can be determined
                   7783: ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less
1.4       misho    7784: ** than zero [SQLITE_ERROR] is returned and no data is written.
1.2       misho    7785: **
                   7786: ** ^An attempt to write to an expired [BLOB handle] fails with an
                   7787: ** error code of [SQLITE_ABORT].  ^Writes to the BLOB that occurred
                   7788: ** before the [BLOB handle] expired are not rolled back by the
                   7789: ** expiration of the handle, though of course those changes might
                   7790: ** have been overwritten by the statement that expired the BLOB handle
                   7791: ** or by other independent statements.
                   7792: **
                   7793: ** This routine only works on a [BLOB handle] which has been created
                   7794: ** by a prior successful call to [sqlite3_blob_open()] and which has not
                   7795: ** been closed by [sqlite3_blob_close()].  Passing any other pointer in
                   7796: ** to this routine results in undefined and probably undesirable behavior.
                   7797: **
                   7798: ** See also: [sqlite3_blob_read()].
                   7799: */
                   7800: SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
                   7801: 
                   7802: /*
                   7803: ** CAPI3REF: Virtual File System Objects
                   7804: **
                   7805: ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
                   7806: ** that SQLite uses to interact
                   7807: ** with the underlying operating system.  Most SQLite builds come with a
                   7808: ** single default VFS that is appropriate for the host computer.
                   7809: ** New VFSes can be registered and existing VFSes can be unregistered.
                   7810: ** The following interfaces are provided.
                   7811: **
                   7812: ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
                   7813: ** ^Names are case sensitive.
                   7814: ** ^Names are zero-terminated UTF-8 strings.
                   7815: ** ^If there is no match, a NULL pointer is returned.
                   7816: ** ^If zVfsName is NULL then the default VFS is returned.
                   7817: **
                   7818: ** ^New VFSes are registered with sqlite3_vfs_register().
                   7819: ** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
                   7820: ** ^The same VFS can be registered multiple times without injury.
                   7821: ** ^To make an existing VFS into the default VFS, register it again
                   7822: ** with the makeDflt flag set.  If two different VFSes with the
                   7823: ** same name are registered, the behavior is undefined.  If a
                   7824: ** VFS is registered with a name that is NULL or an empty string,
                   7825: ** then the behavior is undefined.
                   7826: **
                   7827: ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
                   7828: ** ^(If the default VFS is unregistered, another VFS is chosen as
                   7829: ** the default.  The choice for the new VFS is arbitrary.)^
                   7830: */
                   7831: SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
                   7832: SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
                   7833: SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
                   7834: 
                   7835: /*
                   7836: ** CAPI3REF: Mutexes
                   7837: **
                   7838: ** The SQLite core uses these routines for thread
                   7839: ** synchronization. Though they are intended for internal
                   7840: ** use by SQLite, code that links against SQLite is
                   7841: ** permitted to use any of these routines.
                   7842: **
                   7843: ** The SQLite source code contains multiple implementations
                   7844: ** of these mutex routines.  An appropriate implementation
1.4       misho    7845: ** is selected automatically at compile-time.  The following
1.2       misho    7846: ** implementations are available in the SQLite core:
                   7847: **
                   7848: ** <ul>
                   7849: ** <li>   SQLITE_MUTEX_PTHREADS
                   7850: ** <li>   SQLITE_MUTEX_W32
                   7851: ** <li>   SQLITE_MUTEX_NOOP
1.4       misho    7852: ** </ul>
1.2       misho    7853: **
1.4       misho    7854: ** The SQLITE_MUTEX_NOOP implementation is a set of routines
1.2       misho    7855: ** that does no real locking and is appropriate for use in
1.4       misho    7856: ** a single-threaded application.  The SQLITE_MUTEX_PTHREADS and
1.3       misho    7857: ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
                   7858: ** and Windows.
1.2       misho    7859: **
1.4       misho    7860: ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
1.2       misho    7861: ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
                   7862: ** implementation is included with the library. In this case the
                   7863: ** application must supply a custom mutex implementation using the
                   7864: ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
                   7865: ** before calling sqlite3_initialize() or any other public sqlite3_
1.4       misho    7866: ** function that calls sqlite3_initialize().
1.2       misho    7867: **
                   7868: ** ^The sqlite3_mutex_alloc() routine allocates a new
1.4       misho    7869: ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()
                   7870: ** routine returns NULL if it is unable to allocate the requested
                   7871: ** mutex.  The argument to sqlite3_mutex_alloc() must one of these
                   7872: ** integer constants:
1.2       misho    7873: **
                   7874: ** <ul>
                   7875: ** <li>  SQLITE_MUTEX_FAST
                   7876: ** <li>  SQLITE_MUTEX_RECURSIVE
1.5       misho    7877: ** <li>  SQLITE_MUTEX_STATIC_MAIN
1.2       misho    7878: ** <li>  SQLITE_MUTEX_STATIC_MEM
1.4       misho    7879: ** <li>  SQLITE_MUTEX_STATIC_OPEN
1.2       misho    7880: ** <li>  SQLITE_MUTEX_STATIC_PRNG
                   7881: ** <li>  SQLITE_MUTEX_STATIC_LRU
1.4       misho    7882: ** <li>  SQLITE_MUTEX_STATIC_PMEM
                   7883: ** <li>  SQLITE_MUTEX_STATIC_APP1
                   7884: ** <li>  SQLITE_MUTEX_STATIC_APP2
                   7885: ** <li>  SQLITE_MUTEX_STATIC_APP3
                   7886: ** <li>  SQLITE_MUTEX_STATIC_VFS1
                   7887: ** <li>  SQLITE_MUTEX_STATIC_VFS2
                   7888: ** <li>  SQLITE_MUTEX_STATIC_VFS3
                   7889: ** </ul>
1.2       misho    7890: **
                   7891: ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
                   7892: ** cause sqlite3_mutex_alloc() to create
                   7893: ** a new mutex.  ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
                   7894: ** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
                   7895: ** The mutex implementation does not need to make a distinction
                   7896: ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
1.4       misho    7897: ** not want to.  SQLite will only request a recursive mutex in
                   7898: ** cases where it really needs one.  If a faster non-recursive mutex
1.2       misho    7899: ** implementation is available on the host platform, the mutex subsystem
                   7900: ** might return such a mutex in response to SQLITE_MUTEX_FAST.
                   7901: **
                   7902: ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
                   7903: ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
1.4       misho    7904: ** a pointer to a static preexisting mutex.  ^Nine static mutexes are
1.2       misho    7905: ** used by the current version of SQLite.  Future versions of SQLite
                   7906: ** may add additional static mutexes.  Static mutexes are for internal
                   7907: ** use by SQLite only.  Applications that use SQLite mutexes should
                   7908: ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
                   7909: ** SQLITE_MUTEX_RECURSIVE.
                   7910: **
                   7911: ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
                   7912: ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
1.4       misho    7913: ** returns a different mutex on every call.  ^For the static
1.2       misho    7914: ** mutex types, the same mutex is returned on every call that has
                   7915: ** the same type number.
                   7916: **
                   7917: ** ^The sqlite3_mutex_free() routine deallocates a previously
1.4       misho    7918: ** allocated dynamic mutex.  Attempting to deallocate a static
                   7919: ** mutex results in undefined behavior.
1.2       misho    7920: **
                   7921: ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
                   7922: ** to enter a mutex.  ^If another thread is already within the mutex,
                   7923: ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
                   7924: ** SQLITE_BUSY.  ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
                   7925: ** upon successful entry.  ^(Mutexes created using
                   7926: ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
1.4       misho    7927: ** In such cases, the
1.2       misho    7928: ** mutex must be exited an equal number of times before another thread
1.4       misho    7929: ** can enter.)^  If the same thread tries to enter any mutex other
                   7930: ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.
1.2       misho    7931: **
                   7932: ** ^(Some systems (for example, Windows 95) do not support the operation
                   7933: ** implemented by sqlite3_mutex_try().  On those systems, sqlite3_mutex_try()
1.4       misho    7934: ** will always return SQLITE_BUSY. The SQLite core only ever uses
1.5       misho    7935: ** sqlite3_mutex_try() as an optimization so this is acceptable
1.4       misho    7936: ** behavior.)^
1.2       misho    7937: **
                   7938: ** ^The sqlite3_mutex_leave() routine exits a mutex that was
1.4       misho    7939: ** previously entered by the same thread.   The behavior
1.2       misho    7940: ** is undefined if the mutex is not currently entered by the
1.4       misho    7941: ** calling thread or is not currently allocated.
1.2       misho    7942: **
1.6.2.1 ! misho    7943: ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(),
        !          7944: ** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer,
        !          7945: ** then any of the four routines behaves as a no-op.
1.2       misho    7946: **
                   7947: ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
                   7948: */
                   7949: SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
                   7950: SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
                   7951: SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
                   7952: SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
                   7953: SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
                   7954: 
                   7955: /*
                   7956: ** CAPI3REF: Mutex Methods Object
                   7957: **
                   7958: ** An instance of this structure defines the low-level routines
                   7959: ** used to allocate and use mutexes.
                   7960: **
                   7961: ** Usually, the default mutex implementations provided by SQLite are
1.4       misho    7962: ** sufficient, however the application has the option of substituting a custom
1.2       misho    7963: ** implementation for specialized deployments or systems for which SQLite
1.4       misho    7964: ** does not provide a suitable implementation. In this case, the application
1.2       misho    7965: ** creates and populates an instance of this structure to pass
                   7966: ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
                   7967: ** Additionally, an instance of this structure can be used as an
                   7968: ** output variable when querying the system for the current mutex
                   7969: ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
                   7970: **
                   7971: ** ^The xMutexInit method defined by this structure is invoked as
                   7972: ** part of system initialization by the sqlite3_initialize() function.
                   7973: ** ^The xMutexInit routine is called by SQLite exactly once for each
                   7974: ** effective call to [sqlite3_initialize()].
                   7975: **
                   7976: ** ^The xMutexEnd method defined by this structure is invoked as
                   7977: ** part of system shutdown by the sqlite3_shutdown() function. The
                   7978: ** implementation of this method is expected to release all outstanding
                   7979: ** resources obtained by the mutex methods implementation, especially
                   7980: ** those obtained by the xMutexInit method.  ^The xMutexEnd()
                   7981: ** interface is invoked exactly once for each call to [sqlite3_shutdown()].
                   7982: **
                   7983: ** ^(The remaining seven methods defined by this structure (xMutexAlloc,
                   7984: ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
                   7985: ** xMutexNotheld) implement the following interfaces (respectively):
                   7986: **
                   7987: ** <ul>
                   7988: **   <li>  [sqlite3_mutex_alloc()] </li>
                   7989: **   <li>  [sqlite3_mutex_free()] </li>
                   7990: **   <li>  [sqlite3_mutex_enter()] </li>
                   7991: **   <li>  [sqlite3_mutex_try()] </li>
                   7992: **   <li>  [sqlite3_mutex_leave()] </li>
                   7993: **   <li>  [sqlite3_mutex_held()] </li>
                   7994: **   <li>  [sqlite3_mutex_notheld()] </li>
                   7995: ** </ul>)^
                   7996: **
                   7997: ** The only difference is that the public sqlite3_XXX functions enumerated
                   7998: ** above silently ignore any invocations that pass a NULL pointer instead
                   7999: ** of a valid mutex handle. The implementations of the methods defined
1.5       misho    8000: ** by this structure are not required to handle this case. The results
1.2       misho    8001: ** of passing a NULL pointer instead of a valid mutex handle are undefined
                   8002: ** (i.e. it is acceptable to provide an implementation that segfaults if
                   8003: ** it is passed a NULL pointer).
                   8004: **
1.4       misho    8005: ** The xMutexInit() method must be threadsafe.  It must be harmless to
1.2       misho    8006: ** invoke xMutexInit() multiple times within the same process and without
                   8007: ** intervening calls to xMutexEnd().  Second and subsequent calls to
                   8008: ** xMutexInit() must be no-ops.
                   8009: **
1.4       misho    8010: ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
                   8011: ** and its associates).  Similarly, xMutexAlloc() must not use SQLite memory
1.2       misho    8012: ** allocation for a static mutex.  ^However xMutexAlloc() may use SQLite
                   8013: ** memory allocation for a fast or recursive mutex.
                   8014: **
                   8015: ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
                   8016: ** called, but only if the prior call to xMutexInit returned SQLITE_OK.
                   8017: ** If xMutexInit fails in any way, it is expected to clean up after itself
                   8018: ** prior to returning.
                   8019: */
                   8020: typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
                   8021: struct sqlite3_mutex_methods {
                   8022:   int (*xMutexInit)(void);
                   8023:   int (*xMutexEnd)(void);
                   8024:   sqlite3_mutex *(*xMutexAlloc)(int);
                   8025:   void (*xMutexFree)(sqlite3_mutex *);
                   8026:   void (*xMutexEnter)(sqlite3_mutex *);
                   8027:   int (*xMutexTry)(sqlite3_mutex *);
                   8028:   void (*xMutexLeave)(sqlite3_mutex *);
                   8029:   int (*xMutexHeld)(sqlite3_mutex *);
                   8030:   int (*xMutexNotheld)(sqlite3_mutex *);
                   8031: };
                   8032: 
                   8033: /*
                   8034: ** CAPI3REF: Mutex Verification Routines
                   8035: **
                   8036: ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
1.4       misho    8037: ** are intended for use inside assert() statements.  The SQLite core
1.2       misho    8038: ** never uses these routines except inside an assert() and applications
1.4       misho    8039: ** are advised to follow the lead of the core.  The SQLite core only
1.2       misho    8040: ** provides implementations for these routines when it is compiled
1.4       misho    8041: ** with the SQLITE_DEBUG flag.  External mutex implementations
1.2       misho    8042: ** are only required to provide these routines if SQLITE_DEBUG is
                   8043: ** defined and if NDEBUG is not defined.
                   8044: **
1.4       misho    8045: ** These routines should return true if the mutex in their argument
1.2       misho    8046: ** is held or not held, respectively, by the calling thread.
                   8047: **
1.4       misho    8048: ** The implementation is not required to provide versions of these
1.2       misho    8049: ** routines that actually work. If the implementation does not provide working
                   8050: ** versions of these routines, it should at least provide stubs that always
                   8051: ** return true so that one does not get spurious assertion failures.
                   8052: **
1.4       misho    8053: ** If the argument to sqlite3_mutex_held() is a NULL pointer then
1.2       misho    8054: ** the routine should return 1.   This seems counter-intuitive since
                   8055: ** clearly the mutex cannot be held if it does not exist.  But
                   8056: ** the reason the mutex does not exist is because the build is not
                   8057: ** using mutexes.  And we do not want the assert() containing the
                   8058: ** call to sqlite3_mutex_held() to fail, so a non-zero return is
1.4       misho    8059: ** the appropriate thing to do.  The sqlite3_mutex_notheld()
1.2       misho    8060: ** interface should also return 1 when given a NULL pointer.
                   8061: */
                   8062: #ifndef NDEBUG
                   8063: SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
                   8064: SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
                   8065: #endif
                   8066: 
                   8067: /*
                   8068: ** CAPI3REF: Mutex Types
                   8069: **
                   8070: ** The [sqlite3_mutex_alloc()] interface takes a single argument
                   8071: ** which is one of these integer constants.
                   8072: **
                   8073: ** The set of static mutexes may change from one SQLite release to the
                   8074: ** next.  Applications that override the built-in mutex logic must be
                   8075: ** prepared to accommodate additional static mutexes.
                   8076: */
                   8077: #define SQLITE_MUTEX_FAST             0
                   8078: #define SQLITE_MUTEX_RECURSIVE        1
1.5       misho    8079: #define SQLITE_MUTEX_STATIC_MAIN      2
1.2       misho    8080: #define SQLITE_MUTEX_STATIC_MEM       3  /* sqlite3_malloc() */
                   8081: #define SQLITE_MUTEX_STATIC_MEM2      4  /* NOT USED */
                   8082: #define SQLITE_MUTEX_STATIC_OPEN      4  /* sqlite3BtreeOpen() */
1.5       misho    8083: #define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_randomness() */
1.2       misho    8084: #define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
                   8085: #define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
                   8086: #define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
1.4       misho    8087: #define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
                   8088: #define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
                   8089: #define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */
                   8090: #define SQLITE_MUTEX_STATIC_VFS1     11  /* For use by built-in VFS */
                   8091: #define SQLITE_MUTEX_STATIC_VFS2     12  /* For use by extension VFS */
                   8092: #define SQLITE_MUTEX_STATIC_VFS3     13  /* For use by application VFS */
1.2       misho    8093: 
1.5       misho    8094: /* Legacy compatibility: */
                   8095: #define SQLITE_MUTEX_STATIC_MASTER    2
                   8096: 
                   8097: 
1.2       misho    8098: /*
                   8099: ** CAPI3REF: Retrieve the mutex for a database connection
1.4       misho    8100: ** METHOD: sqlite3
1.2       misho    8101: **
1.5       misho    8102: ** ^This interface returns a pointer the [sqlite3_mutex] object that
1.2       misho    8103: ** serializes access to the [database connection] given in the argument
                   8104: ** when the [threading mode] is Serialized.
                   8105: ** ^If the [threading mode] is Single-thread or Multi-thread then this
                   8106: ** routine returns a NULL pointer.
                   8107: */
                   8108: SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
                   8109: 
                   8110: /*
                   8111: ** CAPI3REF: Low-Level Control Of Database Files
1.4       misho    8112: ** METHOD: sqlite3
1.5       misho    8113: ** KEYWORDS: {file control}
1.2       misho    8114: **
                   8115: ** ^The [sqlite3_file_control()] interface makes a direct call to the
                   8116: ** xFileControl method for the [sqlite3_io_methods] object associated
                   8117: ** with a particular database identified by the second argument. ^The
                   8118: ** name of the database is "main" for the main database or "temp" for the
                   8119: ** TEMP database, or the name that appears after the AS keyword for
                   8120: ** databases that are added using the [ATTACH] SQL command.
                   8121: ** ^A NULL pointer can be used in place of "main" to refer to the
                   8122: ** main database file.
                   8123: ** ^The third and fourth parameters to this routine
                   8124: ** are passed directly through to the second and third parameters of
                   8125: ** the xFileControl method.  ^The return value of the xFileControl
                   8126: ** method becomes the return value of this routine.
                   8127: **
1.5       misho    8128: ** A few opcodes for [sqlite3_file_control()] are handled directly
                   8129: ** by the SQLite core and never invoke the
                   8130: ** sqlite3_io_methods.xFileControl method.
                   8131: ** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes
1.2       misho    8132: ** a pointer to the underlying [sqlite3_file] object to be written into
1.5       misho    8133: ** the space pointed to by the 4th parameter.  The
                   8134: ** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns
                   8135: ** the [sqlite3_file] object associated with the journal file instead of
                   8136: ** the main database.  The [SQLITE_FCNTL_VFS_POINTER] opcode returns
                   8137: ** a pointer to the underlying [sqlite3_vfs] object for the file.
                   8138: ** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter
                   8139: ** from the pager.
1.2       misho    8140: **
                   8141: ** ^If the second parameter (zDbName) does not match the name of any
                   8142: ** open database file, then SQLITE_ERROR is returned.  ^This error
                   8143: ** code is not remembered and will not be recalled by [sqlite3_errcode()]
                   8144: ** or [sqlite3_errmsg()].  The underlying xFileControl method might
                   8145: ** also return SQLITE_ERROR.  There is no way to distinguish between
                   8146: ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
                   8147: ** xFileControl method.
                   8148: **
1.5       misho    8149: ** See also: [file control opcodes]
1.2       misho    8150: */
                   8151: SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
                   8152: 
                   8153: /*
                   8154: ** CAPI3REF: Testing Interface
                   8155: **
                   8156: ** ^The sqlite3_test_control() interface is used to read out internal
                   8157: ** state of SQLite and to inject faults into SQLite for testing
                   8158: ** purposes.  ^The first parameter is an operation code that determines
                   8159: ** the number, meaning, and operation of all subsequent parameters.
                   8160: **
                   8161: ** This interface is not for use by applications.  It exists solely
                   8162: ** for verifying the correct operation of the SQLite library.  Depending
                   8163: ** on how the SQLite library is compiled, this interface might not exist.
                   8164: **
                   8165: ** The details of the operation codes, their meanings, the parameters
                   8166: ** they take, and what they do are all subject to change without notice.
                   8167: ** Unlike most of the SQLite API, this function is not guaranteed to
                   8168: ** operate consistently from one release to the next.
                   8169: */
                   8170: SQLITE_API int sqlite3_test_control(int op, ...);
                   8171: 
                   8172: /*
                   8173: ** CAPI3REF: Testing Interface Operation Codes
                   8174: **
                   8175: ** These constants are the valid operation code parameters used
                   8176: ** as the first argument to [sqlite3_test_control()].
                   8177: **
                   8178: ** These parameters and their meanings are subject to change
                   8179: ** without notice.  These values are for testing purposes only.
                   8180: ** Applications should not use any of these parameters or the
                   8181: ** [sqlite3_test_control()] interface.
                   8182: */
                   8183: #define SQLITE_TESTCTRL_FIRST                    5
                   8184: #define SQLITE_TESTCTRL_PRNG_SAVE                5
                   8185: #define SQLITE_TESTCTRL_PRNG_RESTORE             6
1.5       misho    8186: #define SQLITE_TESTCTRL_PRNG_RESET               7  /* NOT USED */
1.2       misho    8187: #define SQLITE_TESTCTRL_BITVEC_TEST              8
                   8188: #define SQLITE_TESTCTRL_FAULT_INSTALL            9
                   8189: #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS     10
                   8190: #define SQLITE_TESTCTRL_PENDING_BYTE            11
                   8191: #define SQLITE_TESTCTRL_ASSERT                  12
                   8192: #define SQLITE_TESTCTRL_ALWAYS                  13
1.5       misho    8193: #define SQLITE_TESTCTRL_RESERVE                 14  /* NOT USED */
1.2       misho    8194: #define SQLITE_TESTCTRL_OPTIMIZATIONS           15
1.5       misho    8195: #define SQLITE_TESTCTRL_ISKEYWORD               16  /* NOT USED */
                   8196: #define SQLITE_TESTCTRL_SCRATCHMALLOC           17  /* NOT USED */
                   8197: #define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS      17
1.2       misho    8198: #define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
1.4       misho    8199: #define SQLITE_TESTCTRL_EXPLAIN_STMT            19  /* NOT USED */
1.5       misho    8200: #define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD    19
1.4       misho    8201: #define SQLITE_TESTCTRL_NEVER_CORRUPT           20
                   8202: #define SQLITE_TESTCTRL_VDBE_COVERAGE           21
                   8203: #define SQLITE_TESTCTRL_BYTEORDER               22
                   8204: #define SQLITE_TESTCTRL_ISINIT                  23
                   8205: #define SQLITE_TESTCTRL_SORTER_MMAP             24
                   8206: #define SQLITE_TESTCTRL_IMPOSTER                25
1.5       misho    8207: #define SQLITE_TESTCTRL_PARSER_COVERAGE         26
                   8208: #define SQLITE_TESTCTRL_RESULT_INTREAL          27
                   8209: #define SQLITE_TESTCTRL_PRNG_SEED               28
                   8210: #define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS     29
1.6       misho    8211: #define SQLITE_TESTCTRL_SEEK_COUNT              30
                   8212: #define SQLITE_TESTCTRL_TRACEFLAGS              31
1.6.2.1 ! misho    8213: #define SQLITE_TESTCTRL_TUNE                    32
        !          8214: #define SQLITE_TESTCTRL_LOGEST                  33
        !          8215: #define SQLITE_TESTCTRL_USELONGDOUBLE           34
        !          8216: #define SQLITE_TESTCTRL_LAST                    34  /* Largest TESTCTRL */
1.5       misho    8217: 
                   8218: /*
                   8219: ** CAPI3REF: SQL Keyword Checking
                   8220: **
                   8221: ** These routines provide access to the set of SQL language keywords
                   8222: ** recognized by SQLite.  Applications can uses these routines to determine
                   8223: ** whether or not a specific identifier needs to be escaped (for example,
                   8224: ** by enclosing in double-quotes) so as not to confuse the parser.
                   8225: **
                   8226: ** The sqlite3_keyword_count() interface returns the number of distinct
                   8227: ** keywords understood by SQLite.
                   8228: **
                   8229: ** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and
                   8230: ** makes *Z point to that keyword expressed as UTF8 and writes the number
                   8231: ** of bytes in the keyword into *L.  The string that *Z points to is not
                   8232: ** zero-terminated.  The sqlite3_keyword_name(N,Z,L) routine returns
                   8233: ** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z
                   8234: ** or L are NULL or invalid pointers then calls to
                   8235: ** sqlite3_keyword_name(N,Z,L) result in undefined behavior.
                   8236: **
                   8237: ** The sqlite3_keyword_check(Z,L) interface checks to see whether or not
                   8238: ** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero
                   8239: ** if it is and zero if not.
                   8240: **
                   8241: ** The parser used by SQLite is forgiving.  It is often possible to use
                   8242: ** a keyword as an identifier as long as such use does not result in a
                   8243: ** parsing ambiguity.  For example, the statement
                   8244: ** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and
                   8245: ** creates a new table named "BEGIN" with three columns named
                   8246: ** "REPLACE", "PRAGMA", and "END".  Nevertheless, best practice is to avoid
                   8247: ** using keywords as identifiers.  Common techniques used to avoid keyword
                   8248: ** name collisions include:
                   8249: ** <ul>
                   8250: ** <li> Put all identifier names inside double-quotes.  This is the official
                   8251: **      SQL way to escape identifier names.
                   8252: ** <li> Put identifier names inside &#91;...&#93;.  This is not standard SQL,
                   8253: **      but it is what SQL Server does and so lots of programmers use this
                   8254: **      technique.
                   8255: ** <li> Begin every identifier with the letter "Z" as no SQL keywords start
                   8256: **      with "Z".
                   8257: ** <li> Include a digit somewhere in every identifier name.
                   8258: ** </ul>
                   8259: **
                   8260: ** Note that the number of keywords understood by SQLite can depend on
                   8261: ** compile-time options.  For example, "VACUUM" is not a keyword if
                   8262: ** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option.  Also,
                   8263: ** new keywords may be added to future releases of SQLite.
                   8264: */
                   8265: SQLITE_API int sqlite3_keyword_count(void);
                   8266: SQLITE_API int sqlite3_keyword_name(int,const char**,int*);
                   8267: SQLITE_API int sqlite3_keyword_check(const char*,int);
                   8268: 
                   8269: /*
                   8270: ** CAPI3REF: Dynamic String Object
                   8271: ** KEYWORDS: {dynamic string}
                   8272: **
                   8273: ** An instance of the sqlite3_str object contains a dynamically-sized
                   8274: ** string under construction.
                   8275: **
                   8276: ** The lifecycle of an sqlite3_str object is as follows:
                   8277: ** <ol>
                   8278: ** <li> ^The sqlite3_str object is created using [sqlite3_str_new()].
                   8279: ** <li> ^Text is appended to the sqlite3_str object using various
                   8280: ** methods, such as [sqlite3_str_appendf()].
                   8281: ** <li> ^The sqlite3_str object is destroyed and the string it created
                   8282: ** is returned using the [sqlite3_str_finish()] interface.
                   8283: ** </ol>
                   8284: */
                   8285: typedef struct sqlite3_str sqlite3_str;
                   8286: 
                   8287: /*
                   8288: ** CAPI3REF: Create A New Dynamic String Object
                   8289: ** CONSTRUCTOR: sqlite3_str
                   8290: **
                   8291: ** ^The [sqlite3_str_new(D)] interface allocates and initializes
                   8292: ** a new [sqlite3_str] object.  To avoid memory leaks, the object returned by
                   8293: ** [sqlite3_str_new()] must be freed by a subsequent call to
                   8294: ** [sqlite3_str_finish(X)].
                   8295: **
                   8296: ** ^The [sqlite3_str_new(D)] interface always returns a pointer to a
                   8297: ** valid [sqlite3_str] object, though in the event of an out-of-memory
                   8298: ** error the returned object might be a special singleton that will
                   8299: ** silently reject new text, always return SQLITE_NOMEM from
                   8300: ** [sqlite3_str_errcode()], always return 0 for
                   8301: ** [sqlite3_str_length()], and always return NULL from
                   8302: ** [sqlite3_str_finish(X)].  It is always safe to use the value
                   8303: ** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter
                   8304: ** to any of the other [sqlite3_str] methods.
                   8305: **
                   8306: ** The D parameter to [sqlite3_str_new(D)] may be NULL.  If the
                   8307: ** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum
                   8308: ** length of the string contained in the [sqlite3_str] object will be
                   8309: ** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead
                   8310: ** of [SQLITE_MAX_LENGTH].
                   8311: */
                   8312: SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*);
                   8313: 
                   8314: /*
                   8315: ** CAPI3REF: Finalize A Dynamic String
                   8316: ** DESTRUCTOR: sqlite3_str
                   8317: **
                   8318: ** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X
                   8319: ** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()]
                   8320: ** that contains the constructed string.  The calling application should
                   8321: ** pass the returned value to [sqlite3_free()] to avoid a memory leak.
                   8322: ** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any
                   8323: ** errors were encountered during construction of the string.  ^The
                   8324: ** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the
                   8325: ** string in [sqlite3_str] object X is zero bytes long.
                   8326: */
                   8327: SQLITE_API char *sqlite3_str_finish(sqlite3_str*);
                   8328: 
                   8329: /*
                   8330: ** CAPI3REF: Add Content To A Dynamic String
                   8331: ** METHOD: sqlite3_str
                   8332: **
                   8333: ** These interfaces add content to an sqlite3_str object previously obtained
                   8334: ** from [sqlite3_str_new()].
                   8335: **
                   8336: ** ^The [sqlite3_str_appendf(X,F,...)] and
                   8337: ** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf]
                   8338: ** functionality of SQLite to append formatted text onto the end of
                   8339: ** [sqlite3_str] object X.
                   8340: **
                   8341: ** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S
                   8342: ** onto the end of the [sqlite3_str] object X.  N must be non-negative.
                   8343: ** S must contain at least N non-zero bytes of content.  To append a
                   8344: ** zero-terminated string in its entirety, use the [sqlite3_str_appendall()]
                   8345: ** method instead.
                   8346: **
                   8347: ** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of
                   8348: ** zero-terminated string S onto the end of [sqlite3_str] object X.
                   8349: **
                   8350: ** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the
                   8351: ** single-byte character C onto the end of [sqlite3_str] object X.
                   8352: ** ^This method can be used, for example, to add whitespace indentation.
                   8353: **
                   8354: ** ^The [sqlite3_str_reset(X)] method resets the string under construction
                   8355: ** inside [sqlite3_str] object X back to zero bytes in length.
                   8356: **
                   8357: ** These methods do not return a result code.  ^If an error occurs, that fact
                   8358: ** is recorded in the [sqlite3_str] object and can be recovered by a
                   8359: ** subsequent call to [sqlite3_str_errcode(X)].
                   8360: */
                   8361: SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...);
                   8362: SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list);
                   8363: SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N);
                   8364: SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn);
                   8365: SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C);
                   8366: SQLITE_API void sqlite3_str_reset(sqlite3_str*);
                   8367: 
                   8368: /*
                   8369: ** CAPI3REF: Status Of A Dynamic String
                   8370: ** METHOD: sqlite3_str
                   8371: **
                   8372: ** These interfaces return the current status of an [sqlite3_str] object.
                   8373: **
                   8374: ** ^If any prior errors have occurred while constructing the dynamic string
                   8375: ** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return
                   8376: ** an appropriate error code.  ^The [sqlite3_str_errcode(X)] method returns
                   8377: ** [SQLITE_NOMEM] following any out-of-memory error, or
                   8378: ** [SQLITE_TOOBIG] if the size of the dynamic string exceeds
                   8379: ** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors.
                   8380: **
                   8381: ** ^The [sqlite3_str_length(X)] method returns the current length, in bytes,
                   8382: ** of the dynamic string under construction in [sqlite3_str] object X.
                   8383: ** ^The length returned by [sqlite3_str_length(X)] does not include the
                   8384: ** zero-termination byte.
                   8385: **
                   8386: ** ^The [sqlite3_str_value(X)] method returns a pointer to the current
                   8387: ** content of the dynamic string under construction in X.  The value
                   8388: ** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X
                   8389: ** and might be freed or altered by any subsequent method on the same
                   8390: ** [sqlite3_str] object.  Applications must not used the pointer returned
                   8391: ** [sqlite3_str_value(X)] after any subsequent method call on the same
                   8392: ** object.  ^Applications may change the content of the string returned
                   8393: ** by [sqlite3_str_value(X)] as long as they do not write into any bytes
                   8394: ** outside the range of 0 to [sqlite3_str_length(X)] and do not read or
                   8395: ** write any byte after any subsequent sqlite3_str method call.
                   8396: */
                   8397: SQLITE_API int sqlite3_str_errcode(sqlite3_str*);
                   8398: SQLITE_API int sqlite3_str_length(sqlite3_str*);
                   8399: SQLITE_API char *sqlite3_str_value(sqlite3_str*);
1.2       misho    8400: 
                   8401: /*
                   8402: ** CAPI3REF: SQLite Runtime Status
                   8403: **
1.4       misho    8404: ** ^These interfaces are used to retrieve runtime status information
1.2       misho    8405: ** about the performance of SQLite, and optionally to reset various
                   8406: ** highwater marks.  ^The first argument is an integer code for
                   8407: ** the specific parameter to measure.  ^(Recognized integer codes
                   8408: ** are of the form [status parameters | SQLITE_STATUS_...].)^
                   8409: ** ^The current value of the parameter is returned into *pCurrent.
                   8410: ** ^The highest recorded value is returned in *pHighwater.  ^If the
                   8411: ** resetFlag is true, then the highest record value is reset after
                   8412: ** *pHighwater is written.  ^(Some parameters do not record the highest
                   8413: ** value.  For those parameters
                   8414: ** nothing is written into *pHighwater and the resetFlag is ignored.)^
                   8415: ** ^(Other parameters record only the highwater mark and not the current
                   8416: ** value.  For these latter parameters nothing is written into *pCurrent.)^
                   8417: **
1.4       misho    8418: ** ^The sqlite3_status() and sqlite3_status64() routines return
                   8419: ** SQLITE_OK on success and a non-zero [error code] on failure.
1.2       misho    8420: **
1.4       misho    8421: ** If either the current value or the highwater mark is too large to
                   8422: ** be represented by a 32-bit integer, then the values returned by
                   8423: ** sqlite3_status() are undefined.
1.2       misho    8424: **
                   8425: ** See also: [sqlite3_db_status()]
                   8426: */
                   8427: SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
1.4       misho    8428: SQLITE_API int sqlite3_status64(
                   8429:   int op,
                   8430:   sqlite3_int64 *pCurrent,
                   8431:   sqlite3_int64 *pHighwater,
                   8432:   int resetFlag
                   8433: );
1.2       misho    8434: 
                   8435: 
                   8436: /*
                   8437: ** CAPI3REF: Status Parameters
                   8438: ** KEYWORDS: {status parameters}
                   8439: **
                   8440: ** These integer constants designate various run-time status parameters
                   8441: ** that can be returned by [sqlite3_status()].
                   8442: **
                   8443: ** <dl>
                   8444: ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
                   8445: ** <dd>This parameter is the current amount of memory checked out
                   8446: ** using [sqlite3_malloc()], either directly or indirectly.  The
                   8447: ** figure includes calls made to [sqlite3_malloc()] by the application
1.5       misho    8448: ** and internal memory usage by the SQLite library.  Auxiliary page-cache
1.2       misho    8449: ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
                   8450: ** this parameter.  The amount returned is the sum of the allocation
                   8451: ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
                   8452: **
                   8453: ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
                   8454: ** <dd>This parameter records the largest memory allocation request
                   8455: ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
                   8456: ** internal equivalents).  Only the value returned in the
1.5       misho    8457: ** *pHighwater parameter to [sqlite3_status()] is of interest.
1.2       misho    8458: ** The value written into the *pCurrent parameter is undefined.</dd>)^
                   8459: **
                   8460: ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
                   8461: ** <dd>This parameter records the number of separate memory allocations
                   8462: ** currently checked out.</dd>)^
                   8463: **
                   8464: ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
                   8465: ** <dd>This parameter returns the number of pages used out of the
1.5       misho    8466: ** [pagecache memory allocator] that was configured using
1.2       misho    8467: ** [SQLITE_CONFIG_PAGECACHE].  The
                   8468: ** value returned is in pages, not in bytes.</dd>)^
                   8469: **
1.5       misho    8470: ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
1.2       misho    8471: ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
                   8472: ** <dd>This parameter returns the number of bytes of page cache
                   8473: ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
                   8474: ** buffer and where forced to overflow to [sqlite3_malloc()].  The
                   8475: ** returned value includes allocations that overflowed because they
                   8476: ** where too large (they were larger than the "sz" parameter to
                   8477: ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
                   8478: ** no space was left in the page cache.</dd>)^
                   8479: **
                   8480: ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
                   8481: ** <dd>This parameter records the largest memory allocation request
1.5       misho    8482: ** handed to the [pagecache memory allocator].  Only the value returned in the
                   8483: ** *pHighwater parameter to [sqlite3_status()] is of interest.
1.2       misho    8484: ** The value written into the *pCurrent parameter is undefined.</dd>)^
                   8485: **
1.5       misho    8486: ** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt>
                   8487: ** <dd>No longer used.</dd>
1.2       misho    8488: **
                   8489: ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
1.5       misho    8490: ** <dd>No longer used.</dd>
1.2       misho    8491: **
1.5       misho    8492: ** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
                   8493: ** <dd>No longer used.</dd>
1.2       misho    8494: **
                   8495: ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
1.5       misho    8496: ** <dd>The *pHighwater parameter records the deepest parser stack.
1.4       misho    8497: ** The *pCurrent value is undefined.  The *pHighwater value is only
1.2       misho    8498: ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
                   8499: ** </dl>
                   8500: **
                   8501: ** New status parameters may be added from time to time.
                   8502: */
                   8503: #define SQLITE_STATUS_MEMORY_USED          0
                   8504: #define SQLITE_STATUS_PAGECACHE_USED       1
                   8505: #define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
1.5       misho    8506: #define SQLITE_STATUS_SCRATCH_USED         3  /* NOT USED */
                   8507: #define SQLITE_STATUS_SCRATCH_OVERFLOW     4  /* NOT USED */
1.2       misho    8508: #define SQLITE_STATUS_MALLOC_SIZE          5
                   8509: #define SQLITE_STATUS_PARSER_STACK         6
                   8510: #define SQLITE_STATUS_PAGECACHE_SIZE       7
1.5       misho    8511: #define SQLITE_STATUS_SCRATCH_SIZE         8  /* NOT USED */
1.2       misho    8512: #define SQLITE_STATUS_MALLOC_COUNT         9
                   8513: 
                   8514: /*
                   8515: ** CAPI3REF: Database Connection Status
1.4       misho    8516: ** METHOD: sqlite3
1.2       misho    8517: **
1.5       misho    8518: ** ^This interface is used to retrieve runtime status information
1.2       misho    8519: ** about a single [database connection].  ^The first argument is the
                   8520: ** database connection object to be interrogated.  ^The second argument
                   8521: ** is an integer constant, taken from the set of
                   8522: ** [SQLITE_DBSTATUS options], that
1.5       misho    8523: ** determines the parameter to interrogate.  The set of
1.2       misho    8524: ** [SQLITE_DBSTATUS options] is likely
                   8525: ** to grow in future releases of SQLite.
                   8526: **
                   8527: ** ^The current value of the requested parameter is written into *pCur
                   8528: ** and the highest instantaneous value is written into *pHiwtr.  ^If
                   8529: ** the resetFlg is true, then the highest instantaneous value is
                   8530: ** reset back down to the current value.
                   8531: **
                   8532: ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
                   8533: ** non-zero [error code] on failure.
                   8534: **
                   8535: ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
                   8536: */
                   8537: SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
                   8538: 
                   8539: /*
                   8540: ** CAPI3REF: Status Parameters for database connections
                   8541: ** KEYWORDS: {SQLITE_DBSTATUS options}
                   8542: **
                   8543: ** These constants are the available integer "verbs" that can be passed as
                   8544: ** the second argument to the [sqlite3_db_status()] interface.
                   8545: **
                   8546: ** New verbs may be added in future releases of SQLite. Existing verbs
                   8547: ** might be discontinued. Applications should check the return code from
                   8548: ** [sqlite3_db_status()] to make sure that the call worked.
                   8549: ** The [sqlite3_db_status()] interface will return a non-zero error code
                   8550: ** if a discontinued or unsupported verb is invoked.
                   8551: **
                   8552: ** <dl>
                   8553: ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
                   8554: ** <dd>This parameter returns the number of lookaside memory slots currently
                   8555: ** checked out.</dd>)^
                   8556: **
                   8557: ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
1.5       misho    8558: ** <dd>This parameter returns the number of malloc attempts that were
1.2       misho    8559: ** satisfied using lookaside memory. Only the high-water value is meaningful;
                   8560: ** the current value is always zero.)^
                   8561: **
                   8562: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
                   8563: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
                   8564: ** <dd>This parameter returns the number malloc attempts that might have
                   8565: ** been satisfied using lookaside memory but failed due to the amount of
                   8566: ** memory requested being larger than the lookaside slot size.
                   8567: ** Only the high-water value is meaningful;
                   8568: ** the current value is always zero.)^
                   8569: **
                   8570: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
                   8571: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
                   8572: ** <dd>This parameter returns the number malloc attempts that might have
                   8573: ** been satisfied using lookaside memory but failed due to all lookaside
                   8574: ** memory already being in use.
                   8575: ** Only the high-water value is meaningful;
                   8576: ** the current value is always zero.)^
                   8577: **
                   8578: ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
1.4       misho    8579: ** <dd>This parameter returns the approximate number of bytes of heap
1.2       misho    8580: ** memory used by all pager caches associated with the database connection.)^
                   8581: ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
                   8582: **
1.5       misho    8583: ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]]
1.4       misho    8584: ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>
                   8585: ** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a
                   8586: ** pager cache is shared between two or more connections the bytes of heap
                   8587: ** memory used by that pager cache is divided evenly between the attached
                   8588: ** connections.)^  In other words, if none of the pager caches associated
                   8589: ** with the database connection are shared, this request returns the same
                   8590: ** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are
                   8591: ** shared, the value returned by this call will be smaller than that returned
                   8592: ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with
                   8593: ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.
                   8594: **
1.2       misho    8595: ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
1.4       misho    8596: ** <dd>This parameter returns the approximate number of bytes of heap
1.2       misho    8597: ** memory used to store the schema for all databases associated
1.5       misho    8598: ** with the connection - main, temp, and any [ATTACH]-ed databases.)^
1.2       misho    8599: ** ^The full amount of memory used by the schemas is reported, even if the
                   8600: ** schema memory is shared with other database connections due to
                   8601: ** [shared cache mode] being enabled.
                   8602: ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
                   8603: **
                   8604: ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
1.4       misho    8605: ** <dd>This parameter returns the approximate number of bytes of heap
1.2       misho    8606: ** and lookaside memory used by all prepared statements associated with
                   8607: ** the database connection.)^
                   8608: ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
                   8609: ** </dd>
                   8610: **
                   8611: ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
                   8612: ** <dd>This parameter returns the number of pager cache hits that have
1.5       misho    8613: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
1.2       misho    8614: ** is always 0.
                   8615: ** </dd>
                   8616: **
                   8617: ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
                   8618: ** <dd>This parameter returns the number of pager cache misses that have
1.5       misho    8619: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
1.2       misho    8620: ** is always 0.
                   8621: ** </dd>
1.3       misho    8622: **
                   8623: ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>
                   8624: ** <dd>This parameter returns the number of dirty cache entries that have
                   8625: ** been written to disk. Specifically, the number of pages written to the
                   8626: ** wal file in wal mode databases, or the number of pages written to the
                   8627: ** database file in rollback mode databases. Any pages written as part of
                   8628: ** transaction rollback or database recovery operations are not included.
                   8629: ** If an IO or other error occurs while writing a page to disk, the effect
                   8630: ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
                   8631: ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
                   8632: ** </dd>
1.4       misho    8633: **
1.5       misho    8634: ** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt>
                   8635: ** <dd>This parameter returns the number of dirty cache entries that have
                   8636: ** been written to disk in the middle of a transaction due to the page
                   8637: ** cache overflowing. Transactions are more efficient if they are written
                   8638: ** to disk all at once. When pages spill mid-transaction, that introduces
                   8639: ** additional overhead. This parameter can be used help identify
                   8640: ** inefficiencies that can be resolved by increasing the cache size.
                   8641: ** </dd>
                   8642: **
1.4       misho    8643: ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
                   8644: ** <dd>This parameter returns zero for the current value if and only if
                   8645: ** all foreign key constraints (deferred or immediate) have been
                   8646: ** resolved.)^  ^The highwater mark is always 0.
                   8647: ** </dd>
1.2       misho    8648: ** </dl>
                   8649: */
                   8650: #define SQLITE_DBSTATUS_LOOKASIDE_USED       0
                   8651: #define SQLITE_DBSTATUS_CACHE_USED           1
                   8652: #define SQLITE_DBSTATUS_SCHEMA_USED          2
                   8653: #define SQLITE_DBSTATUS_STMT_USED            3
                   8654: #define SQLITE_DBSTATUS_LOOKASIDE_HIT        4
                   8655: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE  5
                   8656: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL  6
                   8657: #define SQLITE_DBSTATUS_CACHE_HIT            7
                   8658: #define SQLITE_DBSTATUS_CACHE_MISS           8
1.3       misho    8659: #define SQLITE_DBSTATUS_CACHE_WRITE          9
1.4       misho    8660: #define SQLITE_DBSTATUS_DEFERRED_FKS        10
                   8661: #define SQLITE_DBSTATUS_CACHE_USED_SHARED   11
1.5       misho    8662: #define SQLITE_DBSTATUS_CACHE_SPILL         12
                   8663: #define SQLITE_DBSTATUS_MAX                 12   /* Largest defined DBSTATUS */
1.2       misho    8664: 
                   8665: 
                   8666: /*
                   8667: ** CAPI3REF: Prepared Statement Status
1.4       misho    8668: ** METHOD: sqlite3_stmt
1.2       misho    8669: **
                   8670: ** ^(Each prepared statement maintains various
                   8671: ** [SQLITE_STMTSTATUS counters] that measure the number
                   8672: ** of times it has performed specific operations.)^  These counters can
                   8673: ** be used to monitor the performance characteristics of the prepared
                   8674: ** statements.  For example, if the number of table steps greatly exceeds
                   8675: ** the number of table searches or result rows, that would tend to indicate
                   8676: ** that the prepared statement is using a full table scan rather than
1.5       misho    8677: ** an index.
1.2       misho    8678: **
                   8679: ** ^(This interface is used to retrieve and reset counter values from
                   8680: ** a [prepared statement].  The first argument is the prepared statement
                   8681: ** object to be interrogated.  The second argument
                   8682: ** is an integer code for a specific [SQLITE_STMTSTATUS counter]
                   8683: ** to be interrogated.)^
                   8684: ** ^The current value of the requested counter is returned.
                   8685: ** ^If the resetFlg is true, then the counter is reset to zero after this
                   8686: ** interface call returns.
                   8687: **
                   8688: ** See also: [sqlite3_status()] and [sqlite3_db_status()].
                   8689: */
                   8690: SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
                   8691: 
                   8692: /*
                   8693: ** CAPI3REF: Status Parameters for prepared statements
                   8694: ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
                   8695: **
                   8696: ** These preprocessor macros define integer codes that name counter
                   8697: ** values associated with the [sqlite3_stmt_status()] interface.
                   8698: ** The meanings of the various counters are as follows:
                   8699: **
                   8700: ** <dl>
                   8701: ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
                   8702: ** <dd>^This is the number of times that SQLite has stepped forward in
                   8703: ** a table as part of a full table scan.  Large numbers for this counter
1.5       misho    8704: ** may indicate opportunities for performance improvement through
1.2       misho    8705: ** careful use of indices.</dd>
                   8706: **
                   8707: ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
                   8708: ** <dd>^This is the number of sort operations that have occurred.
                   8709: ** A non-zero value in this counter may indicate an opportunity to
                   8710: ** improvement performance through careful use of indices.</dd>
                   8711: **
                   8712: ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
                   8713: ** <dd>^This is the number of rows inserted into transient indices that
                   8714: ** were created automatically in order to help joins run faster.
                   8715: ** A non-zero value in this counter may indicate an opportunity to
                   8716: ** improvement performance by adding permanent indices that do not
                   8717: ** need to be reinitialized each time the statement is run.</dd>
1.4       misho    8718: **
                   8719: ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
                   8720: ** <dd>^This is the number of virtual machine operations executed
                   8721: ** by the prepared statement if that number is less than or equal
1.5       misho    8722: ** to 2147483647.  The number of virtual machine operations can be
1.4       misho    8723: ** used as a proxy for the total work done by the prepared statement.
                   8724: ** If the number of virtual machine operations exceeds 2147483647
                   8725: ** then the value returned by this statement status code is undefined.
1.5       misho    8726: **
                   8727: ** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt>
                   8728: ** <dd>^This is the number of times that the prepare statement has been
                   8729: ** automatically regenerated due to schema changes or changes to
                   8730: ** [bound parameters] that might affect the query plan.
                   8731: **
                   8732: ** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt>
                   8733: ** <dd>^This is the number of times that the prepared statement has
                   8734: ** been run.  A single "run" for the purposes of this counter is one
                   8735: ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()].
                   8736: ** The counter is incremented on the first [sqlite3_step()] call of each
                   8737: ** cycle.
                   8738: **
1.6.2.1 ! misho    8739: ** [[SQLITE_STMTSTATUS_FILTER_MISS]]
        !          8740: ** [[SQLITE_STMTSTATUS_FILTER HIT]]
        !          8741: ** <dt>SQLITE_STMTSTATUS_FILTER_HIT<br>
        !          8742: ** SQLITE_STMTSTATUS_FILTER_MISS</dt>
        !          8743: ** <dd>^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join
        !          8744: ** step was bypassed because a Bloom filter returned not-found.  The
        !          8745: ** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of
        !          8746: ** times that the Bloom filter returned a find, and thus the join step
        !          8747: ** had to be processed as normal.
        !          8748: **
1.5       misho    8749: ** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt>
                   8750: ** <dd>^This is the approximate number of bytes of heap memory
                   8751: ** used to store the prepared statement.  ^This value is not actually
                   8752: ** a counter, and so the resetFlg parameter to sqlite3_stmt_status()
                   8753: ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED.
1.4       misho    8754: ** </dd>
1.2       misho    8755: ** </dl>
                   8756: */
                   8757: #define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
                   8758: #define SQLITE_STMTSTATUS_SORT              2
                   8759: #define SQLITE_STMTSTATUS_AUTOINDEX         3
1.4       misho    8760: #define SQLITE_STMTSTATUS_VM_STEP           4
1.5       misho    8761: #define SQLITE_STMTSTATUS_REPREPARE         5
                   8762: #define SQLITE_STMTSTATUS_RUN               6
1.6.2.1 ! misho    8763: #define SQLITE_STMTSTATUS_FILTER_MISS       7
        !          8764: #define SQLITE_STMTSTATUS_FILTER_HIT        8
1.5       misho    8765: #define SQLITE_STMTSTATUS_MEMUSED           99
1.2       misho    8766: 
                   8767: /*
                   8768: ** CAPI3REF: Custom Page Cache Object
                   8769: **
                   8770: ** The sqlite3_pcache type is opaque.  It is implemented by
                   8771: ** the pluggable module.  The SQLite core has no knowledge of
                   8772: ** its size or internal structure and never deals with the
                   8773: ** sqlite3_pcache object except by holding and passing pointers
                   8774: ** to the object.
                   8775: **
                   8776: ** See [sqlite3_pcache_methods2] for additional information.
                   8777: */
                   8778: typedef struct sqlite3_pcache sqlite3_pcache;
                   8779: 
                   8780: /*
                   8781: ** CAPI3REF: Custom Page Cache Object
                   8782: **
                   8783: ** The sqlite3_pcache_page object represents a single page in the
                   8784: ** page cache.  The page cache will allocate instances of this
                   8785: ** object.  Various methods of the page cache use pointers to instances
                   8786: ** of this object as parameters or as their return value.
                   8787: **
                   8788: ** See [sqlite3_pcache_methods2] for additional information.
                   8789: */
                   8790: typedef struct sqlite3_pcache_page sqlite3_pcache_page;
                   8791: struct sqlite3_pcache_page {
                   8792:   void *pBuf;        /* The content of the page */
                   8793:   void *pExtra;      /* Extra information associated with the page */
                   8794: };
                   8795: 
                   8796: /*
                   8797: ** CAPI3REF: Application Defined Page Cache.
                   8798: ** KEYWORDS: {page cache}
                   8799: **
                   8800: ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
1.5       misho    8801: ** register an alternative page cache implementation by passing in an
1.2       misho    8802: ** instance of the sqlite3_pcache_methods2 structure.)^
1.5       misho    8803: ** In many applications, most of the heap memory allocated by
1.2       misho    8804: ** SQLite is used for the page cache.
1.5       misho    8805: ** By implementing a
1.2       misho    8806: ** custom page cache using this API, an application can better control
1.5       misho    8807: ** the amount of memory consumed by SQLite, the way in which
                   8808: ** that memory is allocated and released, and the policies used to
                   8809: ** determine exactly which parts of a database file are cached and for
1.2       misho    8810: ** how long.
                   8811: **
                   8812: ** The alternative page cache mechanism is an
                   8813: ** extreme measure that is only needed by the most demanding applications.
                   8814: ** The built-in page cache is recommended for most uses.
                   8815: **
                   8816: ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
                   8817: ** internal buffer by SQLite within the call to [sqlite3_config].  Hence
                   8818: ** the application may discard the parameter after the call to
                   8819: ** [sqlite3_config()] returns.)^
                   8820: **
                   8821: ** [[the xInit() page cache method]]
1.5       misho    8822: ** ^(The xInit() method is called once for each effective
1.2       misho    8823: ** call to [sqlite3_initialize()])^
                   8824: ** (usually only once during the lifetime of the process). ^(The xInit()
                   8825: ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
1.5       misho    8826: ** The intent of the xInit() method is to set up global data structures
                   8827: ** required by the custom page cache implementation.
                   8828: ** ^(If the xInit() method is NULL, then the
1.2       misho    8829: ** built-in default page cache is used instead of the application defined
                   8830: ** page cache.)^
                   8831: **
                   8832: ** [[the xShutdown() page cache method]]
                   8833: ** ^The xShutdown() method is called by [sqlite3_shutdown()].
1.5       misho    8834: ** It can be used to clean up
1.2       misho    8835: ** any outstanding resources before process shutdown, if required.
                   8836: ** ^The xShutdown() method may be NULL.
                   8837: **
                   8838: ** ^SQLite automatically serializes calls to the xInit method,
                   8839: ** so the xInit method need not be threadsafe.  ^The
                   8840: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
                   8841: ** not need to be threadsafe either.  All other methods must be threadsafe
                   8842: ** in multithreaded applications.
                   8843: **
                   8844: ** ^SQLite will never invoke xInit() more than once without an intervening
                   8845: ** call to xShutdown().
                   8846: **
                   8847: ** [[the xCreate() page cache methods]]
                   8848: ** ^SQLite invokes the xCreate() method to construct a new cache instance.
                   8849: ** SQLite will typically create one cache instance for each open database file,
                   8850: ** though this is not guaranteed. ^The
                   8851: ** first parameter, szPage, is the size in bytes of the pages that must
                   8852: ** be allocated by the cache.  ^szPage will always a power of two.  ^The
1.5       misho    8853: ** second parameter szExtra is a number of bytes of extra storage
1.2       misho    8854: ** associated with each page cache entry.  ^The szExtra parameter will
                   8855: ** a number less than 250.  SQLite will use the
                   8856: ** extra szExtra bytes on each page to store metadata about the underlying
                   8857: ** database page on disk.  The value passed into szExtra depends
                   8858: ** on the SQLite version, the target platform, and how SQLite was compiled.
                   8859: ** ^The third argument to xCreate(), bPurgeable, is true if the cache being
                   8860: ** created will be used to cache database pages of a file stored on disk, or
                   8861: ** false if it is used for an in-memory database. The cache implementation
                   8862: ** does not have to do anything special based with the value of bPurgeable;
                   8863: ** it is purely advisory.  ^On a cache where bPurgeable is false, SQLite will
                   8864: ** never invoke xUnpin() except to deliberately delete a page.
                   8865: ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
1.5       misho    8866: ** false will always have the "discard" flag set to true.
1.2       misho    8867: ** ^Hence, a cache created with bPurgeable false will
                   8868: ** never contain any unpinned pages.
                   8869: **
                   8870: ** [[the xCachesize() page cache method]]
                   8871: ** ^(The xCachesize() method may be called at any time by SQLite to set the
                   8872: ** suggested maximum cache-size (number of pages stored by) the cache
                   8873: ** instance passed as the first argument. This is the value configured using
                   8874: ** the SQLite "[PRAGMA cache_size]" command.)^  As with the bPurgeable
                   8875: ** parameter, the implementation is not required to do anything with this
                   8876: ** value; it is advisory only.
                   8877: **
                   8878: ** [[the xPagecount() page cache methods]]
                   8879: ** The xPagecount() method must return the number of pages currently
                   8880: ** stored in the cache, both pinned and unpinned.
1.5       misho    8881: **
1.2       misho    8882: ** [[the xFetch() page cache methods]]
1.5       misho    8883: ** The xFetch() method locates a page in the cache and returns a pointer to
1.2       misho    8884: ** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
                   8885: ** The pBuf element of the returned sqlite3_pcache_page object will be a
1.5       misho    8886: ** pointer to a buffer of szPage bytes used to store the content of a
1.2       misho    8887: ** single database page.  The pExtra element of sqlite3_pcache_page will be
                   8888: ** a pointer to the szExtra bytes of extra storage that SQLite has requested
                   8889: ** for each entry in the page cache.
                   8890: **
                   8891: ** The page to be fetched is determined by the key. ^The minimum key value
                   8892: ** is 1.  After it has been retrieved using xFetch, the page is considered
                   8893: ** to be "pinned".
                   8894: **
                   8895: ** If the requested page is already in the page cache, then the page cache
                   8896: ** implementation must return a pointer to the page buffer with its content
                   8897: ** intact.  If the requested page is not already in the cache, then the
                   8898: ** cache implementation should use the value of the createFlag
                   8899: ** parameter to help it determined what action to take:
                   8900: **
                   8901: ** <table border=1 width=85% align=center>
1.4       misho    8902: ** <tr><th> createFlag <th> Behavior when page is not already in cache
1.2       misho    8903: ** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
                   8904: ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
                   8905: **                 Otherwise return NULL.
                   8906: ** <tr><td> 2 <td> Make every effort to allocate a new page.  Only return
                   8907: **                 NULL if allocating a new page is effectively impossible.
                   8908: ** </table>
                   8909: **
                   8910: ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1.  SQLite
                   8911: ** will only use a createFlag of 2 after a prior call with a createFlag of 1
1.5       misho    8912: ** failed.)^  In between the xFetch() calls, SQLite may
1.2       misho    8913: ** attempt to unpin one or more cache pages by spilling the content of
                   8914: ** pinned pages to disk and synching the operating system disk cache.
                   8915: **
                   8916: ** [[the xUnpin() page cache method]]
                   8917: ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
                   8918: ** as its second argument.  If the third parameter, discard, is non-zero,
                   8919: ** then the page must be evicted from the cache.
                   8920: ** ^If the discard parameter is
                   8921: ** zero, then the page may be discarded or retained at the discretion of
                   8922: ** page cache implementation. ^The page cache implementation
                   8923: ** may choose to evict unpinned pages at any time.
                   8924: **
1.5       misho    8925: ** The cache must not perform any reference counting. A single
                   8926: ** call to xUnpin() unpins the page regardless of the number of prior calls
1.2       misho    8927: ** to xFetch().
                   8928: **
                   8929: ** [[the xRekey() page cache methods]]
                   8930: ** The xRekey() method is used to change the key value associated with the
                   8931: ** page passed as the second argument. If the cache
                   8932: ** previously contains an entry associated with newKey, it must be
                   8933: ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
                   8934: ** to be pinned.
                   8935: **
                   8936: ** When SQLite calls the xTruncate() method, the cache must discard all
                   8937: ** existing cache entries with page numbers (keys) greater than or equal
                   8938: ** to the value of the iLimit parameter passed to xTruncate(). If any
                   8939: ** of these pages are pinned, they are implicitly unpinned, meaning that
                   8940: ** they can be safely discarded.
                   8941: **
                   8942: ** [[the xDestroy() page cache method]]
                   8943: ** ^The xDestroy() method is used to delete a cache allocated by xCreate().
                   8944: ** All resources associated with the specified cache should be freed. ^After
                   8945: ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
                   8946: ** handle invalid, and will not use it with any other sqlite3_pcache_methods2
                   8947: ** functions.
                   8948: **
                   8949: ** [[the xShrink() page cache method]]
                   8950: ** ^SQLite invokes the xShrink() method when it wants the page cache to
                   8951: ** free up as much of heap memory as possible.  The page cache implementation
                   8952: ** is not obligated to free any memory, but well-behaved implementations should
                   8953: ** do their best.
                   8954: */
                   8955: typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
                   8956: struct sqlite3_pcache_methods2 {
                   8957:   int iVersion;
                   8958:   void *pArg;
                   8959:   int (*xInit)(void*);
                   8960:   void (*xShutdown)(void*);
                   8961:   sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
                   8962:   void (*xCachesize)(sqlite3_pcache*, int nCachesize);
                   8963:   int (*xPagecount)(sqlite3_pcache*);
                   8964:   sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
                   8965:   void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
1.5       misho    8966:   void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
1.2       misho    8967:       unsigned oldKey, unsigned newKey);
                   8968:   void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
                   8969:   void (*xDestroy)(sqlite3_pcache*);
                   8970:   void (*xShrink)(sqlite3_pcache*);
                   8971: };
                   8972: 
                   8973: /*
                   8974: ** This is the obsolete pcache_methods object that has now been replaced
                   8975: ** by sqlite3_pcache_methods2.  This object is not used by SQLite.  It is
                   8976: ** retained in the header file for backwards compatibility only.
                   8977: */
                   8978: typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
                   8979: struct sqlite3_pcache_methods {
                   8980:   void *pArg;
                   8981:   int (*xInit)(void*);
                   8982:   void (*xShutdown)(void*);
                   8983:   sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
                   8984:   void (*xCachesize)(sqlite3_pcache*, int nCachesize);
                   8985:   int (*xPagecount)(sqlite3_pcache*);
                   8986:   void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
                   8987:   void (*xUnpin)(sqlite3_pcache*, void*, int discard);
                   8988:   void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
                   8989:   void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
                   8990:   void (*xDestroy)(sqlite3_pcache*);
                   8991: };
                   8992: 
                   8993: 
                   8994: /*
                   8995: ** CAPI3REF: Online Backup Object
                   8996: **
                   8997: ** The sqlite3_backup object records state information about an ongoing
                   8998: ** online backup operation.  ^The sqlite3_backup object is created by
                   8999: ** a call to [sqlite3_backup_init()] and is destroyed by a call to
                   9000: ** [sqlite3_backup_finish()].
                   9001: **
                   9002: ** See Also: [Using the SQLite Online Backup API]
                   9003: */
                   9004: typedef struct sqlite3_backup sqlite3_backup;
                   9005: 
                   9006: /*
                   9007: ** CAPI3REF: Online Backup API.
                   9008: **
                   9009: ** The backup API copies the content of one database into another.
                   9010: ** It is useful either for creating backups of databases or
1.5       misho    9011: ** for copying in-memory databases to or from persistent files.
1.2       misho    9012: **
                   9013: ** See Also: [Using the SQLite Online Backup API]
                   9014: **
                   9015: ** ^SQLite holds a write transaction open on the destination database file
                   9016: ** for the duration of the backup operation.
                   9017: ** ^The source database is read-locked only while it is being read;
                   9018: ** it is not locked continuously for the entire backup operation.
                   9019: ** ^Thus, the backup may be performed on a live source database without
                   9020: ** preventing other database connections from
                   9021: ** reading or writing to the source database while the backup is underway.
1.5       misho    9022: **
                   9023: ** ^(To perform a backup operation:
1.2       misho    9024: **   <ol>
                   9025: **     <li><b>sqlite3_backup_init()</b> is called once to initialize the
1.5       misho    9026: **         backup,
                   9027: **     <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
1.2       misho    9028: **         the data between the two databases, and finally
1.5       misho    9029: **     <li><b>sqlite3_backup_finish()</b> is called to release all resources
                   9030: **         associated with the backup operation.
1.2       misho    9031: **   </ol>)^
                   9032: ** There should be exactly one call to sqlite3_backup_finish() for each
                   9033: ** successful call to sqlite3_backup_init().
                   9034: **
                   9035: ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
                   9036: **
1.5       misho    9037: ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
                   9038: ** [database connection] associated with the destination database
1.2       misho    9039: ** and the database name, respectively.
                   9040: ** ^The database name is "main" for the main database, "temp" for the
                   9041: ** temporary database, or the name specified after the AS keyword in
                   9042: ** an [ATTACH] statement for an attached database.
1.5       misho    9043: ** ^The S and M arguments passed to
1.2       misho    9044: ** sqlite3_backup_init(D,N,S,M) identify the [database connection]
                   9045: ** and database name of the source database, respectively.
                   9046: ** ^The source and destination [database connections] (parameters S and D)
                   9047: ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
                   9048: ** an error.
                   9049: **
1.5       misho    9050: ** ^A call to sqlite3_backup_init() will fail, returning NULL, if
                   9051: ** there is already a read or read-write transaction open on the
1.4       misho    9052: ** destination database.
                   9053: **
1.2       misho    9054: ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
                   9055: ** returned and an error code and error message are stored in the
                   9056: ** destination [database connection] D.
                   9057: ** ^The error code and message for the failed call to sqlite3_backup_init()
                   9058: ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
                   9059: ** [sqlite3_errmsg16()] functions.
                   9060: ** ^A successful call to sqlite3_backup_init() returns a pointer to an
                   9061: ** [sqlite3_backup] object.
                   9062: ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
1.5       misho    9063: ** sqlite3_backup_finish() functions to perform the specified backup
1.2       misho    9064: ** operation.
                   9065: **
                   9066: ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
                   9067: **
1.5       misho    9068: ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
1.2       misho    9069: ** the source and destination databases specified by [sqlite3_backup] object B.
1.5       misho    9070: ** ^If N is negative, all remaining source pages are copied.
1.2       misho    9071: ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
                   9072: ** are still more pages to be copied, then the function returns [SQLITE_OK].
                   9073: ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
                   9074: ** from source to destination, then it returns [SQLITE_DONE].
                   9075: ** ^If an error occurs while running sqlite3_backup_step(B,N),
                   9076: ** then an [error code] is returned. ^As well as [SQLITE_OK] and
                   9077: ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
                   9078: ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
                   9079: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
                   9080: **
                   9081: ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
                   9082: ** <ol>
                   9083: ** <li> the destination database was opened read-only, or
                   9084: ** <li> the destination database is using write-ahead-log journaling
                   9085: ** and the destination and source page sizes differ, or
                   9086: ** <li> the destination database is an in-memory database and the
                   9087: ** destination and source page sizes differ.
                   9088: ** </ol>)^
                   9089: **
                   9090: ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
                   9091: ** the [sqlite3_busy_handler | busy-handler function]
1.5       misho    9092: ** is invoked (if one is specified). ^If the
                   9093: ** busy-handler returns non-zero before the lock is available, then
1.2       misho    9094: ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
                   9095: ** sqlite3_backup_step() can be retried later. ^If the source
                   9096: ** [database connection]
                   9097: ** is being used to write to the source database when sqlite3_backup_step()
                   9098: ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
                   9099: ** case the call to sqlite3_backup_step() can be retried later on. ^(If
                   9100: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
1.5       misho    9101: ** [SQLITE_READONLY] is returned, then
                   9102: ** there is no point in retrying the call to sqlite3_backup_step(). These
                   9103: ** errors are considered fatal.)^  The application must accept
                   9104: ** that the backup operation has failed and pass the backup operation handle
1.2       misho    9105: ** to the sqlite3_backup_finish() to release associated resources.
                   9106: **
                   9107: ** ^The first call to sqlite3_backup_step() obtains an exclusive lock
1.5       misho    9108: ** on the destination file. ^The exclusive lock is not released until either
                   9109: ** sqlite3_backup_finish() is called or the backup operation is complete
1.2       misho    9110: ** and sqlite3_backup_step() returns [SQLITE_DONE].  ^Every call to
                   9111: ** sqlite3_backup_step() obtains a [shared lock] on the source database that
                   9112: ** lasts for the duration of the sqlite3_backup_step() call.
                   9113: ** ^Because the source database is not locked between calls to
                   9114: ** sqlite3_backup_step(), the source database may be modified mid-way
                   9115: ** through the backup process.  ^If the source database is modified by an
                   9116: ** external process or via a database connection other than the one being
                   9117: ** used by the backup operation, then the backup will be automatically
1.5       misho    9118: ** restarted by the next call to sqlite3_backup_step(). ^If the source
1.2       misho    9119: ** database is modified by the using the same database connection as is used
                   9120: ** by the backup operation, then the backup database is automatically
                   9121: ** updated at the same time.
                   9122: **
                   9123: ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
                   9124: **
1.5       misho    9125: ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
1.2       misho    9126: ** application wishes to abandon the backup operation, the application
                   9127: ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
                   9128: ** ^The sqlite3_backup_finish() interfaces releases all
1.5       misho    9129: ** resources associated with the [sqlite3_backup] object.
1.2       misho    9130: ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
                   9131: ** active write-transaction on the destination database is rolled back.
                   9132: ** The [sqlite3_backup] object is invalid
                   9133: ** and may not be used following a call to sqlite3_backup_finish().
                   9134: **
                   9135: ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
                   9136: ** sqlite3_backup_step() errors occurred, regardless or whether or not
                   9137: ** sqlite3_backup_step() completed.
                   9138: ** ^If an out-of-memory condition or IO error occurred during any prior
                   9139: ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
                   9140: ** sqlite3_backup_finish() returns the corresponding [error code].
                   9141: **
                   9142: ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
                   9143: ** is not a permanent error and does not affect the return value of
                   9144: ** sqlite3_backup_finish().
                   9145: **
1.4       misho    9146: ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]
1.2       misho    9147: ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
                   9148: **
1.4       misho    9149: ** ^The sqlite3_backup_remaining() routine returns the number of pages still
                   9150: ** to be backed up at the conclusion of the most recent sqlite3_backup_step().
                   9151: ** ^The sqlite3_backup_pagecount() routine returns the total number of pages
                   9152: ** in the source database at the conclusion of the most recent
                   9153: ** sqlite3_backup_step().
                   9154: ** ^(The values returned by these functions are only updated by
                   9155: ** sqlite3_backup_step(). If the source database is modified in a way that
                   9156: ** changes the size of the source database or the number of pages remaining,
                   9157: ** those changes are not reflected in the output of sqlite3_backup_pagecount()
                   9158: ** and sqlite3_backup_remaining() until after the next
                   9159: ** sqlite3_backup_step().)^
1.2       misho    9160: **
                   9161: ** <b>Concurrent Usage of Database Handles</b>
                   9162: **
                   9163: ** ^The source [database connection] may be used by the application for other
                   9164: ** purposes while a backup operation is underway or being initialized.
                   9165: ** ^If SQLite is compiled and configured to support threadsafe database
                   9166: ** connections, then the source database connection may be used concurrently
                   9167: ** from within other threads.
                   9168: **
1.5       misho    9169: ** However, the application must guarantee that the destination
                   9170: ** [database connection] is not passed to any other API (by any thread) after
1.2       misho    9171: ** sqlite3_backup_init() is called and before the corresponding call to
                   9172: ** sqlite3_backup_finish().  SQLite does not currently check to see
                   9173: ** if the application incorrectly accesses the destination [database connection]
                   9174: ** and so no error code is reported, but the operations may malfunction
                   9175: ** nevertheless.  Use of the destination database connection while a
1.6.2.1 ! misho    9176: ** backup is in progress might also cause a mutex deadlock.
1.2       misho    9177: **
                   9178: ** If running in [shared cache mode], the application must
                   9179: ** guarantee that the shared cache used by the destination database
                   9180: ** is not accessed while the backup is running. In practice this means
1.5       misho    9181: ** that the application must guarantee that the disk file being
1.2       misho    9182: ** backed up to is not accessed by any connection within the process,
                   9183: ** not just the specific connection that was passed to sqlite3_backup_init().
                   9184: **
1.5       misho    9185: ** The [sqlite3_backup] object itself is partially threadsafe. Multiple
1.2       misho    9186: ** threads may safely make multiple concurrent calls to sqlite3_backup_step().
                   9187: ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
                   9188: ** APIs are not strictly speaking threadsafe. If they are invoked at the
                   9189: ** same time as another thread is invoking sqlite3_backup_step() it is
                   9190: ** possible that they return invalid values.
                   9191: */
                   9192: SQLITE_API sqlite3_backup *sqlite3_backup_init(
                   9193:   sqlite3 *pDest,                        /* Destination database handle */
                   9194:   const char *zDestName,                 /* Destination database name */
                   9195:   sqlite3 *pSource,                      /* Source database handle */
                   9196:   const char *zSourceName                /* Source database name */
                   9197: );
                   9198: SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
                   9199: SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
                   9200: SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
                   9201: SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
                   9202: 
                   9203: /*
                   9204: ** CAPI3REF: Unlock Notification
1.4       misho    9205: ** METHOD: sqlite3
1.2       misho    9206: **
                   9207: ** ^When running in shared-cache mode, a database operation may fail with
                   9208: ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
                   9209: ** individual tables within the shared-cache cannot be obtained. See
1.5       misho    9210: ** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
                   9211: ** ^This API may be used to register a callback that SQLite will invoke
1.2       misho    9212: ** when the connection currently holding the required lock relinquishes it.
                   9213: ** ^This API is only available if the library was compiled with the
                   9214: ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
                   9215: **
                   9216: ** See Also: [Using the SQLite Unlock Notification Feature].
                   9217: **
                   9218: ** ^Shared-cache locks are released when a database connection concludes
1.5       misho    9219: ** its current transaction, either by committing it or rolling it back.
1.2       misho    9220: **
                   9221: ** ^When a connection (known as the blocked connection) fails to obtain a
                   9222: ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
                   9223: ** identity of the database connection (the blocking connection) that
1.5       misho    9224: ** has locked the required resource is stored internally. ^After an
1.2       misho    9225: ** application receives an SQLITE_LOCKED error, it may call the
1.5       misho    9226: ** sqlite3_unlock_notify() method with the blocked connection handle as
1.2       misho    9227: ** the first argument to register for a callback that will be invoked
                   9228: ** when the blocking connections current transaction is concluded. ^The
                   9229: ** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
1.5       misho    9230: ** call that concludes the blocking connection's transaction.
1.2       misho    9231: **
                   9232: ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
                   9233: ** there is a chance that the blocking connection will have already
                   9234: ** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
                   9235: ** If this happens, then the specified callback is invoked immediately,
                   9236: ** from within the call to sqlite3_unlock_notify().)^
                   9237: **
                   9238: ** ^If the blocked connection is attempting to obtain a write-lock on a
                   9239: ** shared-cache table, and more than one other connection currently holds
1.5       misho    9240: ** a read-lock on the same table, then SQLite arbitrarily selects one of
1.2       misho    9241: ** the other connections to use as the blocking connection.
                   9242: **
1.5       misho    9243: ** ^(There may be at most one unlock-notify callback registered by a
1.2       misho    9244: ** blocked connection. If sqlite3_unlock_notify() is called when the
                   9245: ** blocked connection already has a registered unlock-notify callback,
                   9246: ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
                   9247: ** called with a NULL pointer as its second argument, then any existing
1.6.2.1 ! misho    9248: ** unlock-notify callback is cancelled. ^The blocked connections
        !          9249: ** unlock-notify callback may also be cancelled by closing the blocked
1.2       misho    9250: ** connection using [sqlite3_close()].
                   9251: **
                   9252: ** The unlock-notify callback is not reentrant. If an application invokes
                   9253: ** any sqlite3_xxx API functions from within an unlock-notify callback, a
                   9254: ** crash or deadlock may be the result.
                   9255: **
                   9256: ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
                   9257: ** returns SQLITE_OK.
                   9258: **
                   9259: ** <b>Callback Invocation Details</b>
                   9260: **
1.5       misho    9261: ** When an unlock-notify callback is registered, the application provides a
1.2       misho    9262: ** single void* pointer that is passed to the callback when it is invoked.
                   9263: ** However, the signature of the callback function allows SQLite to pass
                   9264: ** it an array of void* context pointers. The first argument passed to
                   9265: ** an unlock-notify callback is a pointer to an array of void* pointers,
                   9266: ** and the second is the number of entries in the array.
                   9267: **
1.5       misho    9268: ** When a blocking connection's transaction is concluded, there may be
1.2       misho    9269: ** more than one blocked connection that has registered for an unlock-notify
                   9270: ** callback. ^If two or more such blocked connections have specified the
                   9271: ** same callback function, then instead of invoking the callback function
                   9272: ** multiple times, it is invoked once with the set of void* context pointers
                   9273: ** specified by the blocked connections bundled together into an array.
1.5       misho    9274: ** This gives the application an opportunity to prioritize any actions
1.2       misho    9275: ** related to the set of unblocked database connections.
                   9276: **
                   9277: ** <b>Deadlock Detection</b>
                   9278: **
1.5       misho    9279: ** Assuming that after registering for an unlock-notify callback a
1.2       misho    9280: ** database waits for the callback to be issued before taking any further
                   9281: ** action (a reasonable assumption), then using this API may cause the
                   9282: ** application to deadlock. For example, if connection X is waiting for
                   9283: ** connection Y's transaction to be concluded, and similarly connection
                   9284: ** Y is waiting on connection X's transaction, then neither connection
                   9285: ** will proceed and the system may remain deadlocked indefinitely.
                   9286: **
                   9287: ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
                   9288: ** detection. ^If a given call to sqlite3_unlock_notify() would put the
                   9289: ** system in a deadlocked state, then SQLITE_LOCKED is returned and no
                   9290: ** unlock-notify callback is registered. The system is said to be in
                   9291: ** a deadlocked state if connection A has registered for an unlock-notify
                   9292: ** callback on the conclusion of connection B's transaction, and connection
                   9293: ** B has itself registered for an unlock-notify callback when connection
                   9294: ** A's transaction is concluded. ^Indirect deadlock is also detected, so
                   9295: ** the system is also considered to be deadlocked if connection B has
                   9296: ** registered for an unlock-notify callback on the conclusion of connection
                   9297: ** C's transaction, where connection C is waiting on connection A. ^Any
                   9298: ** number of levels of indirection are allowed.
                   9299: **
                   9300: ** <b>The "DROP TABLE" Exception</b>
                   9301: **
1.5       misho    9302: ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
1.2       misho    9303: ** always appropriate to call sqlite3_unlock_notify(). There is however,
                   9304: ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
                   9305: ** SQLite checks if there are any currently executing SELECT statements
                   9306: ** that belong to the same connection. If there are, SQLITE_LOCKED is
                   9307: ** returned. In this case there is no "blocking connection", so invoking
                   9308: ** sqlite3_unlock_notify() results in the unlock-notify callback being
                   9309: ** invoked immediately. If the application then re-attempts the "DROP TABLE"
                   9310: ** or "DROP INDEX" query, an infinite loop might be the result.
                   9311: **
                   9312: ** One way around this problem is to check the extended error code returned
                   9313: ** by an sqlite3_step() call. ^(If there is a blocking connection, then the
                   9314: ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
1.5       misho    9315: ** the special "DROP TABLE/INDEX" case, the extended error code is just
1.2       misho    9316: ** SQLITE_LOCKED.)^
                   9317: */
                   9318: SQLITE_API int sqlite3_unlock_notify(
                   9319:   sqlite3 *pBlocked,                          /* Waiting connection */
                   9320:   void (*xNotify)(void **apArg, int nArg),    /* Callback function to invoke */
                   9321:   void *pNotifyArg                            /* Argument to pass to xNotify */
                   9322: );
                   9323: 
                   9324: 
                   9325: /*
                   9326: ** CAPI3REF: String Comparison
                   9327: **
1.3       misho    9328: ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications
                   9329: ** and extensions to compare the contents of two buffers containing UTF-8
                   9330: ** strings in a case-independent fashion, using the same definition of "case
                   9331: ** independence" that SQLite uses internally when comparing identifiers.
1.2       misho    9332: */
1.3       misho    9333: SQLITE_API int sqlite3_stricmp(const char *, const char *);
1.2       misho    9334: SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
                   9335: 
                   9336: /*
1.4       misho    9337: ** CAPI3REF: String Globbing
                   9338: *
                   9339: ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if
                   9340: ** string X matches the [GLOB] pattern P.
                   9341: ** ^The definition of [GLOB] pattern matching used in
                   9342: ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
                   9343: ** SQL dialect understood by SQLite.  ^The [sqlite3_strglob(P,X)] function
                   9344: ** is case sensitive.
                   9345: **
                   9346: ** Note that this routine returns zero on a match and non-zero if the strings
                   9347: ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
                   9348: **
                   9349: ** See also: [sqlite3_strlike()].
                   9350: */
                   9351: SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
                   9352: 
                   9353: /*
                   9354: ** CAPI3REF: String LIKE Matching
                   9355: *
                   9356: ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if
                   9357: ** string X matches the [LIKE] pattern P with escape character E.
                   9358: ** ^The definition of [LIKE] pattern matching used in
                   9359: ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"
                   9360: ** operator in the SQL dialect understood by SQLite.  ^For "X LIKE P" without
                   9361: ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.
                   9362: ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case
                   9363: ** insensitive - equivalent upper and lower case ASCII characters match
                   9364: ** one another.
                   9365: **
                   9366: ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though
                   9367: ** only ASCII characters are case folded.
                   9368: **
                   9369: ** Note that this routine returns zero on a match and non-zero if the strings
                   9370: ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
                   9371: **
                   9372: ** See also: [sqlite3_strglob()].
                   9373: */
                   9374: SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc);
                   9375: 
                   9376: /*
1.2       misho    9377: ** CAPI3REF: Error Logging Interface
                   9378: **
1.4       misho    9379: ** ^The [sqlite3_log()] interface writes a message into the [error log]
1.2       misho    9380: ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
                   9381: ** ^If logging is enabled, the zFormat string and subsequent arguments are
                   9382: ** used with [sqlite3_snprintf()] to generate the final output string.
                   9383: **
                   9384: ** The sqlite3_log() interface is intended for use by extensions such as
                   9385: ** virtual tables, collating functions, and SQL functions.  While there is
                   9386: ** nothing to prevent an application from calling sqlite3_log(), doing so
                   9387: ** is considered bad form.
                   9388: **
                   9389: ** The zFormat string must not be NULL.
                   9390: **
                   9391: ** To avoid deadlocks and other threading problems, the sqlite3_log() routine
                   9392: ** will not use dynamically allocated memory.  The log message is stored in
                   9393: ** a fixed-length buffer on the stack.  If the log message is longer than
                   9394: ** a few hundred characters, it will be truncated to the length of the
                   9395: ** buffer.
                   9396: */
                   9397: SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
                   9398: 
                   9399: /*
                   9400: ** CAPI3REF: Write-Ahead Log Commit Hook
1.4       misho    9401: ** METHOD: sqlite3
1.2       misho    9402: **
                   9403: ** ^The [sqlite3_wal_hook()] function is used to register a callback that
1.4       misho    9404: ** is invoked each time data is committed to a database in wal mode.
1.2       misho    9405: **
1.5       misho    9406: ** ^(The callback is invoked by SQLite after the commit has taken place and
                   9407: ** the associated write-lock on the database released)^, so the implementation
1.2       misho    9408: ** may read, write or [checkpoint] the database as required.
                   9409: **
                   9410: ** ^The first parameter passed to the callback function when it is invoked
                   9411: ** is a copy of the third parameter passed to sqlite3_wal_hook() when
                   9412: ** registering the callback. ^The second is a copy of the database handle.
                   9413: ** ^The third parameter is the name of the database that was written to -
                   9414: ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
                   9415: ** is the number of pages currently in the write-ahead log file,
                   9416: ** including those that were just committed.
                   9417: **
                   9418: ** The callback function should normally return [SQLITE_OK].  ^If an error
                   9419: ** code is returned, that error will propagate back up through the
                   9420: ** SQLite code base to cause the statement that provoked the callback
                   9421: ** to report an error, though the commit will have still occurred. If the
                   9422: ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
                   9423: ** that does not correspond to any valid SQLite error code, the results
                   9424: ** are undefined.
                   9425: **
1.5       misho    9426: ** A single database handle may have at most a single write-ahead log callback
1.2       misho    9427: ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
1.6.2.1 ! misho    9428: ** previously registered write-ahead log callback. ^The return value is
        !          9429: ** a copy of the third parameter from the previous call, if any, or 0.
        !          9430: ** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the
1.2       misho    9431: ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
1.4       misho    9432: ** overwrite any prior [sqlite3_wal_hook()] settings.
1.2       misho    9433: */
                   9434: SQLITE_API void *sqlite3_wal_hook(
1.5       misho    9435:   sqlite3*,
1.2       misho    9436:   int(*)(void *,sqlite3*,const char*,int),
                   9437:   void*
                   9438: );
                   9439: 
                   9440: /*
                   9441: ** CAPI3REF: Configure an auto-checkpoint
1.4       misho    9442: ** METHOD: sqlite3
1.2       misho    9443: **
                   9444: ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
                   9445: ** [sqlite3_wal_hook()] that causes any database on [database connection] D
                   9446: ** to automatically [checkpoint]
                   9447: ** after committing a transaction if there are N or
1.5       misho    9448: ** more frames in the [write-ahead log] file.  ^Passing zero or
1.2       misho    9449: ** a negative value as the nFrame parameter disables automatic
                   9450: ** checkpoints entirely.
                   9451: **
                   9452: ** ^The callback registered by this function replaces any existing callback
                   9453: ** registered using [sqlite3_wal_hook()].  ^Likewise, registering a callback
                   9454: ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
                   9455: ** configured by this function.
                   9456: **
                   9457: ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
                   9458: ** from SQL.
                   9459: **
1.4       misho    9460: ** ^Checkpoints initiated by this mechanism are
                   9461: ** [sqlite3_wal_checkpoint_v2|PASSIVE].
                   9462: **
1.2       misho    9463: ** ^Every new [database connection] defaults to having the auto-checkpoint
                   9464: ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
                   9465: ** pages.  The use of this interface
                   9466: ** is only necessary if the default setting is found to be suboptimal
                   9467: ** for a particular application.
                   9468: */
                   9469: SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
                   9470: 
                   9471: /*
                   9472: ** CAPI3REF: Checkpoint a database
1.4       misho    9473: ** METHOD: sqlite3
1.2       misho    9474: **
1.4       misho    9475: ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to
                   9476: ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^
1.2       misho    9477: **
1.5       misho    9478: ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the
1.4       misho    9479: ** [write-ahead log] for database X on [database connection] D to be
                   9480: ** transferred into the database file and for the write-ahead log to
                   9481: ** be reset.  See the [checkpointing] documentation for addition
                   9482: ** information.
                   9483: **
                   9484: ** This interface used to be the only way to cause a checkpoint to
                   9485: ** occur.  But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]
                   9486: ** interface was added.  This interface is retained for backwards
                   9487: ** compatibility and as a convenience for applications that need to manually
                   9488: ** start a callback but which do not need the full power (and corresponding
                   9489: ** complication) of [sqlite3_wal_checkpoint_v2()].
1.2       misho    9490: */
                   9491: SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
                   9492: 
                   9493: /*
                   9494: ** CAPI3REF: Checkpoint a database
1.4       misho    9495: ** METHOD: sqlite3
1.2       misho    9496: **
1.4       misho    9497: ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint
                   9498: ** operation on database X of [database connection] D in mode M.  Status
                   9499: ** information is written back into integers pointed to by L and C.)^
                   9500: ** ^(The M parameter must be a valid [checkpoint mode]:)^
1.2       misho    9501: **
                   9502: ** <dl>
                   9503: ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
1.5       misho    9504: **   ^Checkpoint as many frames as possible without waiting for any database
                   9505: **   readers or writers to finish, then sync the database file if all frames
1.4       misho    9506: **   in the log were checkpointed. ^The [busy-handler callback]
1.5       misho    9507: **   is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode.
1.4       misho    9508: **   ^On the other hand, passive mode might leave the checkpoint unfinished
                   9509: **   if there are concurrent readers or writers.
1.2       misho    9510: **
                   9511: ** <dt>SQLITE_CHECKPOINT_FULL<dd>
1.4       misho    9512: **   ^This mode blocks (it invokes the
                   9513: **   [sqlite3_busy_handler|busy-handler callback]) until there is no
1.2       misho    9514: **   database writer and all readers are reading from the most recent database
1.4       misho    9515: **   snapshot. ^It then checkpoints all frames in the log file and syncs the
                   9516: **   database file. ^This mode blocks new database writers while it is pending,
                   9517: **   but new database readers are allowed to continue unimpeded.
1.2       misho    9518: **
                   9519: ** <dt>SQLITE_CHECKPOINT_RESTART<dd>
1.4       misho    9520: **   ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition
1.5       misho    9521: **   that after checkpointing the log file it blocks (calls the
1.4       misho    9522: **   [busy-handler callback])
1.5       misho    9523: **   until all readers are reading from the database file only. ^This ensures
1.4       misho    9524: **   that the next writer will restart the log file from the beginning.
                   9525: **   ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new
                   9526: **   database writer attempts while it is pending, but does not impede readers.
                   9527: **
                   9528: ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>
                   9529: **   ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the
                   9530: **   addition that it also truncates the log file to zero bytes just prior
                   9531: **   to a successful return.
1.2       misho    9532: ** </dl>
                   9533: **
1.4       misho    9534: ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in
                   9535: ** the log file or to -1 if the checkpoint could not run because
                   9536: ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not
                   9537: ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the
                   9538: ** log file (including any that were already checkpointed before the function
                   9539: ** was called) or to -1 if the checkpoint could not run due to an error or
                   9540: ** because the database is not in WAL mode. ^Note that upon successful
                   9541: ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been
                   9542: ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.
1.2       misho    9543: **
1.4       misho    9544: ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If
1.5       misho    9545: ** any other process is running a checkpoint operation at the same time, the
                   9546: ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a
1.2       misho    9547: ** busy-handler configured, it will not be invoked in this case.
                   9548: **
1.5       misho    9549: ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the
1.4       misho    9550: ** exclusive "writer" lock on the database file. ^If the writer lock cannot be
                   9551: ** obtained immediately, and a busy-handler is configured, it is invoked and
                   9552: ** the writer lock retried until either the busy-handler returns 0 or the lock
                   9553: ** is successfully obtained. ^The busy-handler is also invoked while waiting for
                   9554: ** database readers as described above. ^If the busy-handler returns 0 before
1.2       misho    9555: ** the writer lock is obtained or while waiting for database readers, the
1.5       misho    9556: ** checkpoint operation proceeds from that point in the same way as
                   9557: ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
1.4       misho    9558: ** without blocking any further. ^SQLITE_BUSY is returned in this case.
1.2       misho    9559: **
1.4       misho    9560: ** ^If parameter zDb is NULL or points to a zero length string, then the
1.5       misho    9561: ** specified operation is attempted on all WAL databases [attached] to
1.4       misho    9562: ** [database connection] db.  In this case the
1.5       misho    9563: ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If
                   9564: ** an SQLITE_BUSY error is encountered when processing one or more of the
                   9565: ** attached WAL databases, the operation is still attempted on any remaining
                   9566: ** attached databases and SQLITE_BUSY is returned at the end. ^If any other
                   9567: ** error occurs while processing an attached database, processing is abandoned
                   9568: ** and the error code is returned to the caller immediately. ^If no error
                   9569: ** (SQLITE_BUSY or otherwise) is encountered while processing the attached
1.2       misho    9570: ** databases, SQLITE_OK is returned.
                   9571: **
1.4       misho    9572: ** ^If database zDb is the name of an attached database that is not in WAL
                   9573: ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If
1.2       misho    9574: ** zDb is not NULL (or a zero length string) and is not the name of any
                   9575: ** attached database, SQLITE_ERROR is returned to the caller.
1.4       misho    9576: **
                   9577: ** ^Unless it returns SQLITE_MISUSE,
                   9578: ** the sqlite3_wal_checkpoint_v2() interface
                   9579: ** sets the error information that is queried by
                   9580: ** [sqlite3_errcode()] and [sqlite3_errmsg()].
                   9581: **
                   9582: ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface
                   9583: ** from SQL.
1.2       misho    9584: */
                   9585: SQLITE_API int sqlite3_wal_checkpoint_v2(
                   9586:   sqlite3 *db,                    /* Database handle */
                   9587:   const char *zDb,                /* Name of attached database (or NULL) */
                   9588:   int eMode,                      /* SQLITE_CHECKPOINT_* value */
                   9589:   int *pnLog,                     /* OUT: Size of WAL log in frames */
                   9590:   int *pnCkpt                     /* OUT: Total number of frames checkpointed */
                   9591: );
                   9592: 
                   9593: /*
1.4       misho    9594: ** CAPI3REF: Checkpoint Mode Values
                   9595: ** KEYWORDS: {checkpoint mode}
1.2       misho    9596: **
1.4       misho    9597: ** These constants define all valid values for the "checkpoint mode" passed
                   9598: ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.
                   9599: ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the
                   9600: ** meaning of each of these checkpoint modes.
                   9601: */
                   9602: #define SQLITE_CHECKPOINT_PASSIVE  0  /* Do as much as possible w/o blocking */
                   9603: #define SQLITE_CHECKPOINT_FULL     1  /* Wait for writers, then checkpoint */
1.6.2.1 ! misho    9604: #define SQLITE_CHECKPOINT_RESTART  2  /* Like FULL but wait for readers */
1.4       misho    9605: #define SQLITE_CHECKPOINT_TRUNCATE 3  /* Like RESTART but also truncate WAL */
1.2       misho    9606: 
                   9607: /*
                   9608: ** CAPI3REF: Virtual Table Interface Configuration
                   9609: **
                   9610: ** This function may be called by either the [xConnect] or [xCreate] method
                   9611: ** of a [virtual table] implementation to configure
                   9612: ** various facets of the virtual table interface.
                   9613: **
                   9614: ** If this interface is invoked outside the context of an xConnect or
                   9615: ** xCreate virtual table method then the behavior is undefined.
                   9616: **
1.5       misho    9617: ** In the call sqlite3_vtab_config(D,C,...) the D parameter is the
                   9618: ** [database connection] in which the virtual table is being created and
                   9619: ** which is passed in as the first argument to the [xConnect] or [xCreate]
                   9620: ** method that is invoking sqlite3_vtab_config().  The C parameter is one
                   9621: ** of the [virtual table configuration options].  The presence and meaning
                   9622: ** of parameters after C depend on which [virtual table configuration option]
                   9623: ** is used.
1.2       misho    9624: */
                   9625: SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
                   9626: 
                   9627: /*
                   9628: ** CAPI3REF: Virtual Table Configuration Options
1.5       misho    9629: ** KEYWORDS: {virtual table configuration options}
                   9630: ** KEYWORDS: {virtual table configuration option}
1.2       misho    9631: **
                   9632: ** These macros define the various options to the
                   9633: ** [sqlite3_vtab_config()] interface that [virtual table] implementations
                   9634: ** can use to customize and optimize their behavior.
                   9635: **
                   9636: ** <dl>
1.5       misho    9637: ** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]]
                   9638: ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt>
1.2       misho    9639: ** <dd>Calls of the form
                   9640: ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
                   9641: ** where X is an integer.  If X is zero, then the [virtual table] whose
                   9642: ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
                   9643: ** support constraints.  In this configuration (which is the default) if
                   9644: ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
                   9645: ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
                   9646: ** specified as part of the users SQL statement, regardless of the actual
                   9647: ** ON CONFLICT mode specified.
                   9648: **
                   9649: ** If X is non-zero, then the virtual table implementation guarantees
                   9650: ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
                   9651: ** any modifications to internal or persistent data structures have been made.
1.5       misho    9652: ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
1.2       misho    9653: ** is able to roll back a statement or database transaction, and abandon
1.5       misho    9654: ** or continue processing the current SQL statement as appropriate.
1.2       misho    9655: ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
                   9656: ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
                   9657: ** had been ABORT.
                   9658: **
                   9659: ** Virtual table implementations that are required to handle OR REPLACE
1.5       misho    9660: ** must do so within the [xUpdate] method. If a call to the
                   9661: ** [sqlite3_vtab_on_conflict()] function indicates that the current ON
                   9662: ** CONFLICT policy is REPLACE, the virtual table implementation should
1.2       misho    9663: ** silently replace the appropriate rows within the xUpdate callback and
                   9664: ** return SQLITE_OK. Or, if this is not possible, it may return
1.5       misho    9665: ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
1.2       misho    9666: ** constraint handling.
1.5       misho    9667: ** </dd>
                   9668: **
                   9669: ** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt>
                   9670: ** <dd>Calls of the form
                   9671: ** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the
1.6.2.1 ! misho    9672: ** the [xConnect] or [xCreate] methods of a [virtual table] implementation
1.5       misho    9673: ** prohibits that virtual table from being used from within triggers and
                   9674: ** views.
                   9675: ** </dd>
                   9676: **
                   9677: ** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt>
                   9678: ** <dd>Calls of the form
                   9679: ** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the
1.6.2.1 ! misho    9680: ** the [xConnect] or [xCreate] methods of a [virtual table] implementation
1.5       misho    9681: ** identify that virtual table as being safe to use from within triggers
                   9682: ** and views.  Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the
                   9683: ** virtual table can do no serious harm even if it is controlled by a
                   9684: ** malicious hacker.  Developers should avoid setting the SQLITE_VTAB_INNOCUOUS
                   9685: ** flag unless absolutely necessary.
                   9686: ** </dd>
1.6.2.1 ! misho    9687: **
        !          9688: ** [[SQLITE_VTAB_USES_ALL_SCHEMAS]]<dt>SQLITE_VTAB_USES_ALL_SCHEMAS</dt>
        !          9689: ** <dd>Calls of the form
        !          9690: ** [sqlite3_vtab_config](db,SQLITE_VTAB_USES_ALL_SCHEMA) from within the
        !          9691: ** the [xConnect] or [xCreate] methods of a [virtual table] implementation
        !          9692: ** instruct the query planner to begin at least a read transaction on
        !          9693: ** all schemas ("main", "temp", and any ATTACH-ed databases) whenever the
        !          9694: ** virtual table is used.
        !          9695: ** </dd>
1.2       misho    9696: ** </dl>
                   9697: */
                   9698: #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
1.5       misho    9699: #define SQLITE_VTAB_INNOCUOUS          2
                   9700: #define SQLITE_VTAB_DIRECTONLY         3
1.6.2.1 ! misho    9701: #define SQLITE_VTAB_USES_ALL_SCHEMAS   4
1.2       misho    9702: 
                   9703: /*
                   9704: ** CAPI3REF: Determine The Virtual Table Conflict Policy
                   9705: **
                   9706: ** This function may only be called from within a call to the [xUpdate] method
                   9707: ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
                   9708: ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
                   9709: ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
                   9710: ** of the SQL statement that triggered the call to the [xUpdate] method of the
                   9711: ** [virtual table].
                   9712: */
                   9713: SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
                   9714: 
                   9715: /*
1.5       misho    9716: ** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE
                   9717: **
                   9718: ** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn]
1.6       misho    9719: ** method of a [virtual table], then it might return true if the
1.5       misho    9720: ** column is being fetched as part of an UPDATE operation during which the
1.6       misho    9721: ** column value will not change.  The virtual table implementation can use
                   9722: ** this hint as permission to substitute a return value that is less
                   9723: ** expensive to compute and that the corresponding
1.5       misho    9724: ** [xUpdate] method understands as a "no-change" value.
                   9725: **
                   9726: ** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that
                   9727: ** the column is not changed by the UPDATE statement, then the xColumn
                   9728: ** method can optionally return without setting a result, without calling
                   9729: ** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces].
                   9730: ** In that case, [sqlite3_value_nochange(X)] will return true for the
                   9731: ** same column in the [xUpdate] method.
1.6       misho    9732: **
                   9733: ** The sqlite3_vtab_nochange() routine is an optimization.  Virtual table
                   9734: ** implementations should continue to give a correct answer even if the
                   9735: ** sqlite3_vtab_nochange() interface were to always return false.  In the
                   9736: ** current implementation, the sqlite3_vtab_nochange() interface does always
                   9737: ** returns false for the enhanced [UPDATE FROM] statement.
1.5       misho    9738: */
                   9739: SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*);
                   9740: 
                   9741: /*
                   9742: ** CAPI3REF: Determine The Collation For a Virtual Table Constraint
1.6.2.1 ! misho    9743: ** METHOD: sqlite3_index_info
1.5       misho    9744: **
                   9745: ** This function may only be called from within a call to the [xBestIndex]
1.6.2.1 ! misho    9746: ** method of a [virtual table].  This function returns a pointer to a string
        !          9747: ** that is the name of the appropriate collation sequence to use for text
        !          9748: ** comparisons on the constraint identified by its arguments.
        !          9749: **
        !          9750: ** The first argument must be the pointer to the [sqlite3_index_info] object
        !          9751: ** that is the first parameter to the xBestIndex() method. The second argument
        !          9752: ** must be an index into the aConstraint[] array belonging to the
        !          9753: ** sqlite3_index_info structure passed to xBestIndex.
        !          9754: **
        !          9755: ** Important:
        !          9756: ** The first parameter must be the same pointer that is passed into the
        !          9757: ** xBestMethod() method.  The first parameter may not be a pointer to a
        !          9758: ** different [sqlite3_index_info] object, even an exact copy.
        !          9759: **
        !          9760: ** The return value is computed as follows:
        !          9761: **
        !          9762: ** <ol>
        !          9763: ** <li><p> If the constraint comes from a WHERE clause expression that contains
        !          9764: **         a [COLLATE operator], then the name of the collation specified by
        !          9765: **         that COLLATE operator is returned.
        !          9766: ** <li><p> If there is no COLLATE operator, but the column that is the subject
        !          9767: **         of the constraint specifies an alternative collating sequence via
        !          9768: **         a [COLLATE clause] on the column definition within the CREATE TABLE
        !          9769: **         statement that was passed into [sqlite3_declare_vtab()], then the
        !          9770: **         name of that alternative collating sequence is returned.
        !          9771: ** <li><p> Otherwise, "BINARY" is returned.
        !          9772: ** </ol>
        !          9773: */
        !          9774: SQLITE_API const char *sqlite3_vtab_collation(sqlite3_index_info*,int);
        !          9775: 
        !          9776: /*
        !          9777: ** CAPI3REF: Determine if a virtual table query is DISTINCT
        !          9778: ** METHOD: sqlite3_index_info
        !          9779: **
        !          9780: ** This API may only be used from within an [xBestIndex|xBestIndex method]
        !          9781: ** of a [virtual table] implementation. The result of calling this
        !          9782: ** interface from outside of xBestIndex() is undefined and probably harmful.
        !          9783: **
        !          9784: ** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and
        !          9785: ** 3.  The integer returned by sqlite3_vtab_distinct()
        !          9786: ** gives the virtual table additional information about how the query
        !          9787: ** planner wants the output to be ordered. As long as the virtual table
        !          9788: ** can meet the ordering requirements of the query planner, it may set
        !          9789: ** the "orderByConsumed" flag.
        !          9790: **
        !          9791: ** <ol><li value="0"><p>
        !          9792: ** ^If the sqlite3_vtab_distinct() interface returns 0, that means
        !          9793: ** that the query planner needs the virtual table to return all rows in the
        !          9794: ** sort order defined by the "nOrderBy" and "aOrderBy" fields of the
        !          9795: ** [sqlite3_index_info] object.  This is the default expectation.  If the
        !          9796: ** virtual table outputs all rows in sorted order, then it is always safe for
        !          9797: ** the xBestIndex method to set the "orderByConsumed" flag, regardless of
        !          9798: ** the return value from sqlite3_vtab_distinct().
        !          9799: ** <li value="1"><p>
        !          9800: ** ^(If the sqlite3_vtab_distinct() interface returns 1, that means
        !          9801: ** that the query planner does not need the rows to be returned in sorted order
        !          9802: ** as long as all rows with the same values in all columns identified by the
        !          9803: ** "aOrderBy" field are adjacent.)^  This mode is used when the query planner
        !          9804: ** is doing a GROUP BY.
        !          9805: ** <li value="2"><p>
        !          9806: ** ^(If the sqlite3_vtab_distinct() interface returns 2, that means
        !          9807: ** that the query planner does not need the rows returned in any particular
        !          9808: ** order, as long as rows with the same values in all "aOrderBy" columns
        !          9809: ** are adjacent.)^  ^(Furthermore, only a single row for each particular
        !          9810: ** combination of values in the columns identified by the "aOrderBy" field
        !          9811: ** needs to be returned.)^  ^It is always ok for two or more rows with the same
        !          9812: ** values in all "aOrderBy" columns to be returned, as long as all such rows
        !          9813: ** are adjacent.  ^The virtual table may, if it chooses, omit extra rows
        !          9814: ** that have the same value for all columns identified by "aOrderBy".
        !          9815: ** ^However omitting the extra rows is optional.
        !          9816: ** This mode is used for a DISTINCT query.
        !          9817: ** <li value="3"><p>
        !          9818: ** ^(If the sqlite3_vtab_distinct() interface returns 3, that means
        !          9819: ** that the query planner needs only distinct rows but it does need the
        !          9820: ** rows to be sorted.)^ ^The virtual table implementation is free to omit
        !          9821: ** rows that are identical in all aOrderBy columns, if it wants to, but
        !          9822: ** it is not required to omit any rows.  This mode is used for queries
        !          9823: ** that have both DISTINCT and ORDER BY clauses.
        !          9824: ** </ol>
        !          9825: **
        !          9826: ** ^For the purposes of comparing virtual table output values to see if the
        !          9827: ** values are same value for sorting purposes, two NULL values are considered
        !          9828: ** to be the same.  In other words, the comparison operator is "IS"
        !          9829: ** (or "IS NOT DISTINCT FROM") and not "==".
        !          9830: **
        !          9831: ** If a virtual table implementation is unable to meet the requirements
        !          9832: ** specified above, then it must not set the "orderByConsumed" flag in the
        !          9833: ** [sqlite3_index_info] object or an incorrect answer may result.
        !          9834: **
        !          9835: ** ^A virtual table implementation is always free to return rows in any order
        !          9836: ** it wants, as long as the "orderByConsumed" flag is not set.  ^When the
        !          9837: ** the "orderByConsumed" flag is unset, the query planner will add extra
        !          9838: ** [bytecode] to ensure that the final results returned by the SQL query are
        !          9839: ** ordered correctly.  The use of the "orderByConsumed" flag and the
        !          9840: ** sqlite3_vtab_distinct() interface is merely an optimization.  ^Careful
        !          9841: ** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed"
        !          9842: ** flag might help queries against a virtual table to run faster.  Being
        !          9843: ** overly aggressive and setting the "orderByConsumed" flag when it is not
        !          9844: ** valid to do so, on the other hand, might cause SQLite to return incorrect
        !          9845: ** results.
        !          9846: */
        !          9847: SQLITE_API int sqlite3_vtab_distinct(sqlite3_index_info*);
        !          9848: 
        !          9849: /*
        !          9850: ** CAPI3REF: Identify and handle IN constraints in xBestIndex
        !          9851: **
        !          9852: ** This interface may only be used from within an
        !          9853: ** [xBestIndex|xBestIndex() method] of a [virtual table] implementation.
        !          9854: ** The result of invoking this interface from any other context is
        !          9855: ** undefined and probably harmful.
        !          9856: **
        !          9857: ** ^(A constraint on a virtual table of the form
        !          9858: ** "[IN operator|column IN (...)]" is
        !          9859: ** communicated to the xBestIndex method as a
        !          9860: ** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^  If xBestIndex wants to use
        !          9861: ** this constraint, it must set the corresponding
        !          9862: ** aConstraintUsage[].argvIndex to a positive integer.  ^(Then, under
        !          9863: ** the usual mode of handling IN operators, SQLite generates [bytecode]
        !          9864: ** that invokes the [xFilter|xFilter() method] once for each value
        !          9865: ** on the right-hand side of the IN operator.)^  Thus the virtual table
        !          9866: ** only sees a single value from the right-hand side of the IN operator
        !          9867: ** at a time.
        !          9868: **
        !          9869: ** In some cases, however, it would be advantageous for the virtual
        !          9870: ** table to see all values on the right-hand of the IN operator all at
        !          9871: ** once.  The sqlite3_vtab_in() interfaces facilitates this in two ways:
        !          9872: **
        !          9873: ** <ol>
        !          9874: ** <li><p>
        !          9875: **   ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero)
        !          9876: **   if and only if the [sqlite3_index_info|P->aConstraint][N] constraint
        !          9877: **   is an [IN operator] that can be processed all at once.  ^In other words,
        !          9878: **   sqlite3_vtab_in() with -1 in the third argument is a mechanism
        !          9879: **   by which the virtual table can ask SQLite if all-at-once processing
        !          9880: **   of the IN operator is even possible.
        !          9881: **
        !          9882: ** <li><p>
        !          9883: **   ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates
        !          9884: **   to SQLite that the virtual table does or does not want to process
        !          9885: **   the IN operator all-at-once, respectively.  ^Thus when the third
        !          9886: **   parameter (F) is non-negative, this interface is the mechanism by
        !          9887: **   which the virtual table tells SQLite how it wants to process the
        !          9888: **   IN operator.
        !          9889: ** </ol>
        !          9890: **
        !          9891: ** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times
        !          9892: ** within the same xBestIndex method call.  ^For any given P,N pair,
        !          9893: ** the return value from sqlite3_vtab_in(P,N,F) will always be the same
        !          9894: ** within the same xBestIndex call.  ^If the interface returns true
        !          9895: ** (non-zero), that means that the constraint is an IN operator
        !          9896: ** that can be processed all-at-once.  ^If the constraint is not an IN
        !          9897: ** operator or cannot be processed all-at-once, then the interface returns
        !          9898: ** false.
        !          9899: **
        !          9900: ** ^(All-at-once processing of the IN operator is selected if both of the
        !          9901: ** following conditions are met:
        !          9902: **
        !          9903: ** <ol>
        !          9904: ** <li><p> The P->aConstraintUsage[N].argvIndex value is set to a positive
        !          9905: ** integer.  This is how the virtual table tells SQLite that it wants to
        !          9906: ** use the N-th constraint.
        !          9907: **
        !          9908: ** <li><p> The last call to sqlite3_vtab_in(P,N,F) for which F was
        !          9909: ** non-negative had F>=1.
        !          9910: ** </ol>)^
        !          9911: **
        !          9912: ** ^If either or both of the conditions above are false, then SQLite uses
        !          9913: ** the traditional one-at-a-time processing strategy for the IN constraint.
        !          9914: ** ^If both conditions are true, then the argvIndex-th parameter to the
        !          9915: ** xFilter method will be an [sqlite3_value] that appears to be NULL,
        !          9916: ** but which can be passed to [sqlite3_vtab_in_first()] and
        !          9917: ** [sqlite3_vtab_in_next()] to find all values on the right-hand side
        !          9918: ** of the IN constraint.
        !          9919: */
        !          9920: SQLITE_API int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle);
        !          9921: 
        !          9922: /*
        !          9923: ** CAPI3REF: Find all elements on the right-hand side of an IN constraint.
        !          9924: **
        !          9925: ** These interfaces are only useful from within the
        !          9926: ** [xFilter|xFilter() method] of a [virtual table] implementation.
        !          9927: ** The result of invoking these interfaces from any other context
        !          9928: ** is undefined and probably harmful.
        !          9929: **
        !          9930: ** The X parameter in a call to sqlite3_vtab_in_first(X,P) or
        !          9931: ** sqlite3_vtab_in_next(X,P) should be one of the parameters to the
        !          9932: ** xFilter method which invokes these routines, and specifically
        !          9933: ** a parameter that was previously selected for all-at-once IN constraint
        !          9934: ** processing use the [sqlite3_vtab_in()] interface in the
        !          9935: ** [xBestIndex|xBestIndex method].  ^(If the X parameter is not
        !          9936: ** an xFilter argument that was selected for all-at-once IN constraint
        !          9937: ** processing, then these routines return [SQLITE_ERROR].)^
        !          9938: **
        !          9939: ** ^(Use these routines to access all values on the right-hand side
        !          9940: ** of the IN constraint using code like the following:
        !          9941: **
        !          9942: ** <blockquote><pre>
        !          9943: ** &nbsp;  for(rc=sqlite3_vtab_in_first(pList, &pVal);
        !          9944: ** &nbsp;      rc==SQLITE_OK && pVal;
        !          9945: ** &nbsp;      rc=sqlite3_vtab_in_next(pList, &pVal)
        !          9946: ** &nbsp;  ){
        !          9947: ** &nbsp;    // do something with pVal
        !          9948: ** &nbsp;  }
        !          9949: ** &nbsp;  if( rc!=SQLITE_OK ){
        !          9950: ** &nbsp;    // an error has occurred
        !          9951: ** &nbsp;  }
        !          9952: ** </pre></blockquote>)^
        !          9953: **
        !          9954: ** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P)
        !          9955: ** routines return SQLITE_OK and set *P to point to the first or next value
        !          9956: ** on the RHS of the IN constraint.  ^If there are no more values on the
        !          9957: ** right hand side of the IN constraint, then *P is set to NULL and these
        !          9958: ** routines return [SQLITE_DONE].  ^The return value might be
        !          9959: ** some other value, such as SQLITE_NOMEM, in the event of a malfunction.
        !          9960: **
        !          9961: ** The *ppOut values returned by these routines are only valid until the
        !          9962: ** next call to either of these routines or until the end of the xFilter
        !          9963: ** method from which these routines were called.  If the virtual table
        !          9964: ** implementation needs to retain the *ppOut values for longer, it must make
        !          9965: ** copies.  The *ppOut values are [protected sqlite3_value|protected].
        !          9966: */
        !          9967: SQLITE_API int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut);
        !          9968: SQLITE_API int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut);
        !          9969: 
        !          9970: /*
        !          9971: ** CAPI3REF: Constraint values in xBestIndex()
        !          9972: ** METHOD: sqlite3_index_info
        !          9973: **
        !          9974: ** This API may only be used from within the [xBestIndex|xBestIndex method]
        !          9975: ** of a [virtual table] implementation. The result of calling this interface
        !          9976: ** from outside of an xBestIndex method are undefined and probably harmful.
        !          9977: **
        !          9978: ** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within
        !          9979: ** the [xBestIndex] method of a [virtual table] implementation, with P being
        !          9980: ** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and
        !          9981: ** J being a 0-based index into P->aConstraint[], then this routine
        !          9982: ** attempts to set *V to the value of the right-hand operand of
        !          9983: ** that constraint if the right-hand operand is known.  ^If the
        !          9984: ** right-hand operand is not known, then *V is set to a NULL pointer.
        !          9985: ** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if
        !          9986: ** and only if *V is set to a value.  ^The sqlite3_vtab_rhs_value(P,J,V)
        !          9987: ** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th
        !          9988: ** constraint is not available.  ^The sqlite3_vtab_rhs_value() interface
        !          9989: ** can return an result code other than SQLITE_OK or SQLITE_NOTFOUND if
        !          9990: ** something goes wrong.
        !          9991: **
        !          9992: ** The sqlite3_vtab_rhs_value() interface is usually only successful if
        !          9993: ** the right-hand operand of a constraint is a literal value in the original
        !          9994: ** SQL statement.  If the right-hand operand is an expression or a reference
        !          9995: ** to some other column or a [host parameter], then sqlite3_vtab_rhs_value()
        !          9996: ** will probably return [SQLITE_NOTFOUND].
        !          9997: **
        !          9998: ** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and
        !          9999: ** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand.  For such
        !          10000: ** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^
        !          10001: **
        !          10002: ** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value
        !          10003: ** and remains valid for the duration of the xBestIndex method call.
        !          10004: ** ^When xBestIndex returns, the sqlite3_value object returned by
        !          10005: ** sqlite3_vtab_rhs_value() is automatically deallocated.
1.5       misho    10006: **
1.6.2.1 ! misho    10007: ** The "_rhs_" in the name of this routine is an abbreviation for
        !          10008: ** "Right-Hand Side".
1.5       misho    10009: */
1.6.2.1 ! misho    10010: SQLITE_API int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal);
1.5       misho    10011: 
                   10012: /*
1.2       misho    10013: ** CAPI3REF: Conflict resolution modes
1.4       misho    10014: ** KEYWORDS: {conflict resolution mode}
1.2       misho    10015: **
                   10016: ** These constants are returned by [sqlite3_vtab_on_conflict()] to
                   10017: ** inform a [virtual table] implementation what the [ON CONFLICT] mode
                   10018: ** is for the SQL statement being evaluated.
                   10019: **
                   10020: ** Note that the [SQLITE_IGNORE] constant is also used as a potential
                   10021: ** return value from the [sqlite3_set_authorizer()] callback and that
                   10022: ** [SQLITE_ABORT] is also a [result code].
                   10023: */
                   10024: #define SQLITE_ROLLBACK 1
                   10025: /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
                   10026: #define SQLITE_FAIL     3
                   10027: /* #define SQLITE_ABORT 4  // Also an error code */
                   10028: #define SQLITE_REPLACE  5
                   10029: 
1.4       misho    10030: /*
                   10031: ** CAPI3REF: Prepared Statement Scan Status Opcodes
                   10032: ** KEYWORDS: {scanstatus options}
                   10033: **
                   10034: ** The following constants can be used for the T parameter to the
                   10035: ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface.  Each constant designates a
                   10036: ** different metric for sqlite3_stmt_scanstatus() to return.
                   10037: **
                   10038: ** When the value returned to V is a string, space to hold that string is
                   10039: ** managed by the prepared statement S and will be automatically freed when
                   10040: ** S is finalized.
                   10041: **
1.6.2.1 ! misho    10042: ** Not all values are available for all query elements. When a value is
        !          10043: ** not available, the output variable is set to -1 if the value is numeric,
        !          10044: ** or to NULL if it is a string (SQLITE_SCANSTAT_NAME).
        !          10045: **
1.4       misho    10046: ** <dl>
                   10047: ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>
1.5       misho    10048: ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be
1.4       misho    10049: ** set to the total number of times that the X-th loop has run.</dd>
                   10050: **
                   10051: ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>
1.5       misho    10052: ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set
1.4       misho    10053: ** to the total number of rows examined by all iterations of the X-th loop.</dd>
                   10054: **
                   10055: ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>
1.5       misho    10056: ** <dd>^The "double" variable pointed to by the V parameter will be set to the
1.4       misho    10057: ** query planner's estimate for the average number of rows output from each
                   10058: ** iteration of the X-th loop.  If the query planner's estimates was accurate,
                   10059: ** then this value will approximate the quotient NVISIT/NLOOP and the
                   10060: ** product of this value for all prior loops with the same SELECTID will
                   10061: ** be the NLOOP value for the current loop.
                   10062: **
                   10063: ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>
1.5       misho    10064: ** <dd>^The "const char *" variable pointed to by the V parameter will be set
1.4       misho    10065: ** to a zero-terminated UTF-8 string containing the name of the index or table
                   10066: ** used for the X-th loop.
                   10067: **
                   10068: ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>
1.5       misho    10069: ** <dd>^The "const char *" variable pointed to by the V parameter will be set
1.4       misho    10070: ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]
                   10071: ** description for the X-th loop.
                   10072: **
1.6.2.1 ! misho    10073: ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECTID</dt>
1.5       misho    10074: ** <dd>^The "int" variable pointed to by the V parameter will be set to the
1.6.2.1 ! misho    10075: ** id for the X-th query plan element. The id value is unique within the
        !          10076: ** statement. The select-id is the same value as is output in the first
        !          10077: ** column of an [EXPLAIN QUERY PLAN] query.
        !          10078: **
        !          10079: ** [[SQLITE_SCANSTAT_PARENTID]] <dt>SQLITE_SCANSTAT_PARENTID</dt>
        !          10080: ** <dd>The "int" variable pointed to by the V parameter will be set to the
        !          10081: ** the id of the parent of the current query element, if applicable, or
        !          10082: ** to zero if the query element has no parent. This is the same value as
        !          10083: ** returned in the second column of an [EXPLAIN QUERY PLAN] query.
        !          10084: **
        !          10085: ** [[SQLITE_SCANSTAT_NCYCLE]] <dt>SQLITE_SCANSTAT_NCYCLE</dt>
        !          10086: ** <dd>The sqlite3_int64 output value is set to the number of cycles,
        !          10087: ** according to the processor time-stamp counter, that elapsed while the
        !          10088: ** query element was being processed. This value is not available for
        !          10089: ** all query elements - if it is unavailable the output variable is
        !          10090: ** set to -1.
1.4       misho    10091: ** </dl>
                   10092: */
                   10093: #define SQLITE_SCANSTAT_NLOOP    0
                   10094: #define SQLITE_SCANSTAT_NVISIT   1
                   10095: #define SQLITE_SCANSTAT_EST      2
                   10096: #define SQLITE_SCANSTAT_NAME     3
                   10097: #define SQLITE_SCANSTAT_EXPLAIN  4
                   10098: #define SQLITE_SCANSTAT_SELECTID 5
1.6.2.1 ! misho    10099: #define SQLITE_SCANSTAT_PARENTID 6
        !          10100: #define SQLITE_SCANSTAT_NCYCLE   7
1.4       misho    10101: 
                   10102: /*
                   10103: ** CAPI3REF: Prepared Statement Scan Status
                   10104: ** METHOD: sqlite3_stmt
                   10105: **
1.6.2.1 ! misho    10106: ** These interfaces return information about the predicted and measured
1.4       misho    10107: ** performance for pStmt.  Advanced applications can use this
                   10108: ** interface to compare the predicted and the measured performance and
                   10109: ** issue warnings and/or rerun [ANALYZE] if discrepancies are found.
                   10110: **
                   10111: ** Since this interface is expected to be rarely used, it is only
                   10112: ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]
                   10113: ** compile-time option.
                   10114: **
                   10115: ** The "iScanStatusOp" parameter determines which status information to return.
                   10116: ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior
1.6.2.1 ! misho    10117: ** of this interface is undefined. ^The requested measurement is written into
        !          10118: ** a variable pointed to by the "pOut" parameter.
        !          10119: **
        !          10120: ** The "flags" parameter must be passed a mask of flags. At present only
        !          10121: ** one flag is defined - SQLITE_SCANSTAT_COMPLEX. If SQLITE_SCANSTAT_COMPLEX
        !          10122: ** is specified, then status information is available for all elements
        !          10123: ** of a query plan that are reported by "EXPLAIN QUERY PLAN" output. If
        !          10124: ** SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements
        !          10125: ** that correspond to query loops (the "SCAN..." and "SEARCH..." elements of
        !          10126: ** the EXPLAIN QUERY PLAN output) are available. Invoking API
        !          10127: ** sqlite3_stmt_scanstatus() is equivalent to calling
        !          10128: ** sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter.
        !          10129: **
        !          10130: ** Parameter "idx" identifies the specific query element to retrieve statistics
        !          10131: ** for. Query elements are numbered starting from zero. A value of -1 may be
        !          10132: ** to query for statistics regarding the entire query. ^If idx is out of range
        !          10133: ** - less than -1 or greater than or equal to the total number of query
        !          10134: ** elements used to implement the statement - a non-zero value is returned and
        !          10135: ** the variable that pOut points to is unchanged.
1.4       misho    10136: **
                   10137: ** See also: [sqlite3_stmt_scanstatus_reset()]
                   10138: */
                   10139: SQLITE_API int sqlite3_stmt_scanstatus(
                   10140:   sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
                   10141:   int idx,                  /* Index of loop to report on */
                   10142:   int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
                   10143:   void *pOut                /* Result written here */
1.5       misho    10144: );
1.6.2.1 ! misho    10145: SQLITE_API int sqlite3_stmt_scanstatus_v2(
        !          10146:   sqlite3_stmt *pStmt,      /* Prepared statement for which info desired */
        !          10147:   int idx,                  /* Index of loop to report on */
        !          10148:   int iScanStatusOp,        /* Information desired.  SQLITE_SCANSTAT_* */
        !          10149:   int flags,                /* Mask of flags defined below */
        !          10150:   void *pOut                /* Result written here */
        !          10151: );
        !          10152: 
        !          10153: /*
        !          10154: ** CAPI3REF: Prepared Statement Scan Status
        !          10155: ** KEYWORDS: {scan status flags}
        !          10156: */
        !          10157: #define SQLITE_SCANSTAT_COMPLEX 0x0001
1.4       misho    10158: 
                   10159: /*
                   10160: ** CAPI3REF: Zero Scan-Status Counters
                   10161: ** METHOD: sqlite3_stmt
                   10162: **
                   10163: ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.
                   10164: **
                   10165: ** This API is only available if the library is built with pre-processor
                   10166: ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.
                   10167: */
                   10168: SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
                   10169: 
                   10170: /*
                   10171: ** CAPI3REF: Flush caches to disk mid-transaction
1.6       misho    10172: ** METHOD: sqlite3
1.4       misho    10173: **
                   10174: ** ^If a write-transaction is open on [database connection] D when the
                   10175: ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
1.5       misho    10176: ** pages in the pager-cache that are not currently in use are written out
1.4       misho    10177: ** to disk. A dirty page may be in use if a database cursor created by an
                   10178: ** active SQL statement is reading from it, or if it is page 1 of a database
                   10179: ** file (page 1 is always "in use").  ^The [sqlite3_db_cacheflush(D)]
                   10180: ** interface flushes caches for all schemas - "main", "temp", and
                   10181: ** any [attached] databases.
                   10182: **
1.5       misho    10183: ** ^If this function needs to obtain extra database locks before dirty pages
                   10184: ** can be flushed to disk, it does so. ^If those locks cannot be obtained
1.4       misho    10185: ** immediately and there is a busy-handler callback configured, it is invoked
                   10186: ** in the usual manner. ^If the required lock still cannot be obtained, then
                   10187: ** the database is skipped and an attempt made to flush any dirty pages
                   10188: ** belonging to the next (if any) database. ^If any databases are skipped
                   10189: ** because locks cannot be obtained, but no other error occurs, this
                   10190: ** function returns SQLITE_BUSY.
                   10191: **
                   10192: ** ^If any other error occurs while flushing dirty pages to disk (for
                   10193: ** example an IO error or out-of-memory condition), then processing is
                   10194: ** abandoned and an SQLite [error code] is returned to the caller immediately.
                   10195: **
                   10196: ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.
                   10197: **
                   10198: ** ^This function does not set the database handle error code or message
                   10199: ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.
                   10200: */
                   10201: SQLITE_API int sqlite3_db_cacheflush(sqlite3*);
                   10202: 
                   10203: /*
                   10204: ** CAPI3REF: The pre-update hook.
1.6       misho    10205: ** METHOD: sqlite3
1.4       misho    10206: **
                   10207: ** ^These interfaces are only available if SQLite is compiled using the
                   10208: ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.
                   10209: **
                   10210: ** ^The [sqlite3_preupdate_hook()] interface registers a callback function
                   10211: ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation
1.5       misho    10212: ** on a database table.
1.4       misho    10213: ** ^At most one preupdate hook may be registered at a time on a single
                   10214: ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides
                   10215: ** the previous setting.
                   10216: ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]
                   10217: ** with a NULL pointer as the second parameter.
                   10218: ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as
                   10219: ** the first parameter to callbacks.
                   10220: **
1.5       misho    10221: ** ^The preupdate hook only fires for changes to real database tables; the
                   10222: ** preupdate hook is not invoked for changes to [virtual tables] or to
                   10223: ** system tables like sqlite_sequence or sqlite_stat1.
1.4       misho    10224: **
                   10225: ** ^The second parameter to the preupdate callback is a pointer to
                   10226: ** the [database connection] that registered the preupdate hook.
                   10227: ** ^The third parameter to the preupdate callback is one of the constants
                   10228: ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the
                   10229: ** kind of update operation that is about to occur.
                   10230: ** ^(The fourth parameter to the preupdate callback is the name of the
                   10231: ** database within the database connection that is being modified.  This
1.5       misho    10232: ** will be "main" for the main database or "temp" for TEMP tables or
1.4       misho    10233: ** the name given after the AS keyword in the [ATTACH] statement for attached
                   10234: ** databases.)^
                   10235: ** ^The fifth parameter to the preupdate callback is the name of the
                   10236: ** table that is being modified.
1.5       misho    10237: **
                   10238: ** For an UPDATE or DELETE operation on a [rowid table], the sixth
                   10239: ** parameter passed to the preupdate callback is the initial [rowid] of the
                   10240: ** row being modified or deleted. For an INSERT operation on a rowid table,
                   10241: ** or any operation on a WITHOUT ROWID table, the value of the sixth
                   10242: ** parameter is undefined. For an INSERT or UPDATE on a rowid table the
                   10243: ** seventh parameter is the final rowid value of the row being inserted
                   10244: ** or updated. The value of the seventh parameter passed to the callback
                   10245: ** function is not defined for operations on WITHOUT ROWID tables, or for
1.6       misho    10246: ** DELETE operations on rowid tables.
1.4       misho    10247: **
1.6.2.1 ! misho    10248: ** ^The sqlite3_preupdate_hook(D,C,P) function returns the P argument from
        !          10249: ** the previous call on the same [database connection] D, or NULL for
        !          10250: ** the first call on D.
        !          10251: **
1.4       misho    10252: ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],
                   10253: ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces
                   10254: ** provide additional information about a preupdate event. These routines
                   10255: ** may only be called from within a preupdate callback.  Invoking any of
                   10256: ** these routines from outside of a preupdate callback or with a
                   10257: ** [database connection] pointer that is different from the one supplied
                   10258: ** to the preupdate callback results in undefined and probably undesirable
                   10259: ** behavior.
                   10260: **
                   10261: ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns
                   10262: ** in the row that is being inserted, updated, or deleted.
                   10263: **
                   10264: ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to
                   10265: ** a [protected sqlite3_value] that contains the value of the Nth column of
                   10266: ** the table row before it is updated.  The N parameter must be between 0
                   10267: ** and one less than the number of columns or the behavior will be
                   10268: ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE
                   10269: ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the
                   10270: ** behavior is undefined.  The [sqlite3_value] that P points to
                   10271: ** will be destroyed when the preupdate callback returns.
                   10272: **
                   10273: ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to
                   10274: ** a [protected sqlite3_value] that contains the value of the Nth column of
                   10275: ** the table row after it is updated.  The N parameter must be between 0
                   10276: ** and one less than the number of columns or the behavior will be
                   10277: ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE
                   10278: ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the
                   10279: ** behavior is undefined.  The [sqlite3_value] that P points to
                   10280: ** will be destroyed when the preupdate callback returns.
                   10281: **
                   10282: ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate
                   10283: ** callback was invoked as a result of a direct insert, update, or delete
1.5       misho    10284: ** operation; or 1 for inserts, updates, or deletes invoked by top-level
1.4       misho    10285: ** triggers; or 2 for changes resulting from triggers called by top-level
                   10286: ** triggers; and so forth.
                   10287: **
1.6.2.1 ! misho    10288: ** When the [sqlite3_blob_write()] API is used to update a blob column,
        !          10289: ** the pre-update hook is invoked with SQLITE_DELETE. This is because the
        !          10290: ** in this case the new values are not available. In this case, when a
        !          10291: ** callback made with op==SQLITE_DELETE is actually a write using the
        !          10292: ** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns
        !          10293: ** the index of the column being written. In other cases, where the
        !          10294: ** pre-update hook is being invoked for some other reason, including a
        !          10295: ** regular DELETE, sqlite3_preupdate_blobwrite() returns -1.
        !          10296: **
1.4       misho    10297: ** See also:  [sqlite3_update_hook()]
                   10298: */
1.5       misho    10299: #if defined(SQLITE_ENABLE_PREUPDATE_HOOK)
                   10300: SQLITE_API void *sqlite3_preupdate_hook(
1.4       misho    10301:   sqlite3 *db,
                   10302:   void(*xPreUpdate)(
                   10303:     void *pCtx,                   /* Copy of third arg to preupdate_hook() */
                   10304:     sqlite3 *db,                  /* Database handle */
                   10305:     int op,                       /* SQLITE_UPDATE, DELETE or INSERT */
                   10306:     char const *zDb,              /* Database name */
                   10307:     char const *zName,            /* Table name */
                   10308:     sqlite3_int64 iKey1,          /* Rowid of row about to be deleted/updated */
                   10309:     sqlite3_int64 iKey2           /* New rowid value (for a rowid UPDATE) */
                   10310:   ),
                   10311:   void*
                   10312: );
1.5       misho    10313: SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **);
                   10314: SQLITE_API int sqlite3_preupdate_count(sqlite3 *);
                   10315: SQLITE_API int sqlite3_preupdate_depth(sqlite3 *);
                   10316: SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **);
1.6.2.1 ! misho    10317: SQLITE_API int sqlite3_preupdate_blobwrite(sqlite3 *);
1.5       misho    10318: #endif
1.4       misho    10319: 
                   10320: /*
                   10321: ** CAPI3REF: Low-level system error code
1.6       misho    10322: ** METHOD: sqlite3
1.4       misho    10323: **
                   10324: ** ^Attempt to return the underlying operating system error code or error
                   10325: ** number that caused the most recent I/O error or failure to open a file.
                   10326: ** The return value is OS-dependent.  For example, on unix systems, after
                   10327: ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be
                   10328: ** called to get back the underlying "errno" that caused the problem, such
1.5       misho    10329: ** as ENOSPC, EAUTH, EISDIR, and so forth.
1.4       misho    10330: */
                   10331: SQLITE_API int sqlite3_system_errno(sqlite3*);
                   10332: 
                   10333: /*
                   10334: ** CAPI3REF: Database Snapshot
1.5       misho    10335: ** KEYWORDS: {snapshot} {sqlite3_snapshot}
1.4       misho    10336: **
                   10337: ** An instance of the snapshot object records the state of a [WAL mode]
                   10338: ** database for some specific point in history.
                   10339: **
                   10340: ** In [WAL mode], multiple [database connections] that are open on the
                   10341: ** same database file can each be reading a different historical version
                   10342: ** of the database file.  When a [database connection] begins a read
                   10343: ** transaction, that connection sees an unchanging copy of the database
                   10344: ** as it existed for the point in time when the transaction first started.
                   10345: ** Subsequent changes to the database from other connections are not seen
                   10346: ** by the reader until a new read transaction is started.
                   10347: **
                   10348: ** The sqlite3_snapshot object records state information about an historical
                   10349: ** version of the database file so that it is possible to later open a new read
                   10350: ** transaction that sees that historical version of the database rather than
                   10351: ** the most recent version.
                   10352: */
1.5       misho    10353: typedef struct sqlite3_snapshot {
                   10354:   unsigned char hidden[48];
                   10355: } sqlite3_snapshot;
1.4       misho    10356: 
                   10357: /*
                   10358: ** CAPI3REF: Record A Database Snapshot
1.5       misho    10359: ** CONSTRUCTOR: sqlite3_snapshot
1.4       misho    10360: **
                   10361: ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a
                   10362: ** new [sqlite3_snapshot] object that records the current state of
                   10363: ** schema S in database connection D.  ^On success, the
                   10364: ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly
                   10365: ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.
1.5       misho    10366: ** If there is not already a read-transaction open on schema S when
                   10367: ** this function is called, one is opened automatically.
                   10368: **
                   10369: ** The following must be true for this function to succeed. If any of
                   10370: ** the following statements are false when sqlite3_snapshot_get() is
                   10371: ** called, SQLITE_ERROR is returned. The final value of *P is undefined
                   10372: ** in this case.
                   10373: **
                   10374: ** <ul>
                   10375: **   <li> The database handle must not be in [autocommit mode].
                   10376: **
                   10377: **   <li> Schema S of [database connection] D must be a [WAL mode] database.
                   10378: **
                   10379: **   <li> There must not be a write transaction open on schema S of database
                   10380: **        connection D.
                   10381: **
                   10382: **   <li> One or more transactions must have been written to the current wal
                   10383: **        file since it was created on disk (by any connection). This means
                   10384: **        that a snapshot cannot be taken on a wal mode database with no wal
                   10385: **        file immediately after it is first opened. At least one transaction
                   10386: **        must be written to it first.
                   10387: ** </ul>
                   10388: **
                   10389: ** This function may also return SQLITE_NOMEM.  If it is called with the
                   10390: ** database handle in autocommit mode but fails for some other reason,
                   10391: ** whether or not a read transaction is opened on schema S is undefined.
1.4       misho    10392: **
                   10393: ** The [sqlite3_snapshot] object returned from a successful call to
                   10394: ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]
                   10395: ** to avoid a memory leak.
                   10396: **
                   10397: ** The [sqlite3_snapshot_get()] interface is only available when the
1.5       misho    10398: ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
1.4       misho    10399: */
                   10400: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get(
                   10401:   sqlite3 *db,
                   10402:   const char *zSchema,
                   10403:   sqlite3_snapshot **ppSnapshot
                   10404: );
                   10405: 
                   10406: /*
                   10407: ** CAPI3REF: Start a read transaction on an historical snapshot
1.5       misho    10408: ** METHOD: sqlite3_snapshot
                   10409: **
                   10410: ** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read
                   10411: ** transaction or upgrades an existing one for schema S of
                   10412: ** [database connection] D such that the read transaction refers to
                   10413: ** historical [snapshot] P, rather than the most recent change to the
                   10414: ** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK
                   10415: ** on success or an appropriate [error code] if it fails.
                   10416: **
                   10417: ** ^In order to succeed, the database connection must not be in
                   10418: ** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there
                   10419: ** is already a read transaction open on schema S, then the database handle
                   10420: ** must have no active statements (SELECT statements that have been passed
                   10421: ** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()).
                   10422: ** SQLITE_ERROR is returned if either of these conditions is violated, or
                   10423: ** if schema S does not exist, or if the snapshot object is invalid.
                   10424: **
                   10425: ** ^A call to sqlite3_snapshot_open() will fail to open if the specified
                   10426: ** snapshot has been overwritten by a [checkpoint]. In this case
                   10427: ** SQLITE_ERROR_SNAPSHOT is returned.
                   10428: **
                   10429: ** If there is already a read transaction open when this function is
                   10430: ** invoked, then the same read transaction remains open (on the same
                   10431: ** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT
                   10432: ** is returned. If another error code - for example SQLITE_PROTOCOL or an
                   10433: ** SQLITE_IOERR error code - is returned, then the final state of the
                   10434: ** read transaction is undefined. If SQLITE_OK is returned, then the
                   10435: ** read transaction is now open on database snapshot P.
1.4       misho    10436: **
                   10437: ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the
                   10438: ** database connection D does not know that the database file for
                   10439: ** schema S is in [WAL mode].  A database connection might not know
                   10440: ** that the database file is in [WAL mode] if there has been no prior
1.5       misho    10441: ** I/O on that database connection, or if the database entered [WAL mode]
1.4       misho    10442: ** after the most recent I/O on the database connection.)^
                   10443: ** (Hint: Run "[PRAGMA application_id]" against a newly opened
                   10444: ** database connection in order to make it ready to use snapshots.)
                   10445: **
                   10446: ** The [sqlite3_snapshot_open()] interface is only available when the
1.5       misho    10447: ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
1.4       misho    10448: */
                   10449: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open(
                   10450:   sqlite3 *db,
                   10451:   const char *zSchema,
                   10452:   sqlite3_snapshot *pSnapshot
                   10453: );
                   10454: 
                   10455: /*
                   10456: ** CAPI3REF: Destroy a snapshot
1.5       misho    10457: ** DESTRUCTOR: sqlite3_snapshot
1.4       misho    10458: **
                   10459: ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.
                   10460: ** The application must eventually free every [sqlite3_snapshot] object
                   10461: ** using this routine to avoid a memory leak.
                   10462: **
                   10463: ** The [sqlite3_snapshot_free()] interface is only available when the
1.5       misho    10464: ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used.
1.4       misho    10465: */
                   10466: SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*);
1.2       misho    10467: 
1.4       misho    10468: /*
                   10469: ** CAPI3REF: Compare the ages of two snapshot handles.
1.5       misho    10470: ** METHOD: sqlite3_snapshot
1.4       misho    10471: **
                   10472: ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages
1.5       misho    10473: ** of two valid snapshot handles.
1.4       misho    10474: **
1.5       misho    10475: ** If the two snapshot handles are not associated with the same database
                   10476: ** file, the result of the comparison is undefined.
1.4       misho    10477: **
                   10478: ** Additionally, the result of the comparison is only valid if both of the
                   10479: ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the
                   10480: ** last time the wal file was deleted. The wal file is deleted when the
                   10481: ** database is changed back to rollback mode or when the number of database
1.5       misho    10482: ** clients drops to zero. If either snapshot handle was obtained before the
                   10483: ** wal file was last deleted, the value returned by this function
1.4       misho    10484: ** is undefined.
                   10485: **
                   10486: ** Otherwise, this API returns a negative value if P1 refers to an older
                   10487: ** snapshot than P2, zero if the two handles refer to the same database
                   10488: ** snapshot, and a positive value if P1 is a newer snapshot than P2.
1.5       misho    10489: **
                   10490: ** This interface is only available if SQLite is compiled with the
                   10491: ** [SQLITE_ENABLE_SNAPSHOT] option.
1.4       misho    10492: */
                   10493: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp(
                   10494:   sqlite3_snapshot *p1,
                   10495:   sqlite3_snapshot *p2
                   10496: );
1.2       misho    10497: 
                   10498: /*
1.5       misho    10499: ** CAPI3REF: Recover snapshots from a wal file
                   10500: ** METHOD: sqlite3_snapshot
                   10501: **
                   10502: ** If a [WAL file] remains on disk after all database connections close
                   10503: ** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control]
                   10504: ** or because the last process to have the database opened exited without
                   10505: ** calling [sqlite3_close()]) and a new connection is subsequently opened
                   10506: ** on that database and [WAL file], the [sqlite3_snapshot_open()] interface
                   10507: ** will only be able to open the last transaction added to the WAL file
                   10508: ** even though the WAL file contains other valid transactions.
                   10509: **
                   10510: ** This function attempts to scan the WAL file associated with database zDb
                   10511: ** of database handle db and make all valid snapshots available to
                   10512: ** sqlite3_snapshot_open(). It is an error if there is already a read
                   10513: ** transaction open on the database, or if the database is not a WAL mode
                   10514: ** database.
                   10515: **
                   10516: ** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
                   10517: **
                   10518: ** This interface is only available if SQLite is compiled with the
                   10519: ** [SQLITE_ENABLE_SNAPSHOT] option.
                   10520: */
                   10521: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb);
                   10522: 
                   10523: /*
                   10524: ** CAPI3REF: Serialize a database
                   10525: **
                   10526: ** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory
                   10527: ** that is a serialization of the S database on [database connection] D.
                   10528: ** If P is not a NULL pointer, then the size of the database in bytes
                   10529: ** is written into *P.
                   10530: **
                   10531: ** For an ordinary on-disk database file, the serialization is just a
                   10532: ** copy of the disk file.  For an in-memory database or a "TEMP" database,
                   10533: ** the serialization is the same sequence of bytes which would be written
                   10534: ** to disk if that database where backed up to disk.
                   10535: **
                   10536: ** The usual case is that sqlite3_serialize() copies the serialization of
                   10537: ** the database into memory obtained from [sqlite3_malloc64()] and returns
                   10538: ** a pointer to that memory.  The caller is responsible for freeing the
                   10539: ** returned value to avoid a memory leak.  However, if the F argument
                   10540: ** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations
                   10541: ** are made, and the sqlite3_serialize() function will return a pointer
                   10542: ** to the contiguous memory representation of the database that SQLite
                   10543: ** is currently using for that database, or NULL if the no such contiguous
                   10544: ** memory representation of the database exists.  A contiguous memory
                   10545: ** representation of the database will usually only exist if there has
                   10546: ** been a prior call to [sqlite3_deserialize(D,S,...)] with the same
                   10547: ** values of D and S.
                   10548: ** The size of the database is written into *P even if the
                   10549: ** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy
                   10550: ** of the database exists.
                   10551: **
                   10552: ** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the
                   10553: ** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory
                   10554: ** allocation error occurs.
                   10555: **
1.6.2.1 ! misho    10556: ** This interface is omitted if SQLite is compiled with the
        !          10557: ** [SQLITE_OMIT_DESERIALIZE] option.
1.5       misho    10558: */
                   10559: SQLITE_API unsigned char *sqlite3_serialize(
                   10560:   sqlite3 *db,           /* The database connection */
                   10561:   const char *zSchema,   /* Which DB to serialize. ex: "main", "temp", ... */
                   10562:   sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */
                   10563:   unsigned int mFlags    /* Zero or more SQLITE_SERIALIZE_* flags */
                   10564: );
                   10565: 
                   10566: /*
                   10567: ** CAPI3REF: Flags for sqlite3_serialize
                   10568: **
                   10569: ** Zero or more of the following constants can be OR-ed together for
                   10570: ** the F argument to [sqlite3_serialize(D,S,P,F)].
                   10571: **
                   10572: ** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return
                   10573: ** a pointer to contiguous in-memory database that it is currently using,
                   10574: ** without making a copy of the database.  If SQLite is not currently using
                   10575: ** a contiguous in-memory database, then this option causes
                   10576: ** [sqlite3_serialize()] to return a NULL pointer.  SQLite will only be
                   10577: ** using a contiguous in-memory database if it has been initialized by a
                   10578: ** prior call to [sqlite3_deserialize()].
                   10579: */
                   10580: #define SQLITE_SERIALIZE_NOCOPY 0x001   /* Do no memory allocations */
                   10581: 
                   10582: /*
                   10583: ** CAPI3REF: Deserialize a database
                   10584: **
                   10585: ** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the
                   10586: ** [database connection] D to disconnect from database S and then
                   10587: ** reopen S as an in-memory database based on the serialization contained
                   10588: ** in P.  The serialized database P is N bytes in size.  M is the size of
                   10589: ** the buffer P, which might be larger than N.  If M is larger than N, and
                   10590: ** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is
                   10591: ** permitted to add content to the in-memory database as long as the total
                   10592: ** size does not exceed M bytes.
                   10593: **
                   10594: ** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will
                   10595: ** invoke sqlite3_free() on the serialization buffer when the database
                   10596: ** connection closes.  If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then
                   10597: ** SQLite will try to increase the buffer size using sqlite3_realloc64()
                   10598: ** if writes on the database cause it to grow larger than M bytes.
                   10599: **
                   10600: ** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the
                   10601: ** database is currently in a read transaction or is involved in a backup
                   10602: ** operation.
                   10603: **
1.6.2.1 ! misho    10604: ** It is not possible to deserialized into the TEMP database.  If the
        !          10605: ** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the
        !          10606: ** function returns SQLITE_ERROR.
        !          10607: **
1.5       misho    10608: ** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the
                   10609: ** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then
                   10610: ** [sqlite3_free()] is invoked on argument P prior to returning.
                   10611: **
1.6.2.1 ! misho    10612: ** This interface is omitted if SQLite is compiled with the
        !          10613: ** [SQLITE_OMIT_DESERIALIZE] option.
1.5       misho    10614: */
                   10615: SQLITE_API int sqlite3_deserialize(
                   10616:   sqlite3 *db,            /* The database connection */
                   10617:   const char *zSchema,    /* Which DB to reopen with the deserialization */
                   10618:   unsigned char *pData,   /* The serialized database content */
                   10619:   sqlite3_int64 szDb,     /* Number bytes in the deserialization */
                   10620:   sqlite3_int64 szBuf,    /* Total size of buffer pData[] */
                   10621:   unsigned mFlags         /* Zero or more SQLITE_DESERIALIZE_* flags */
                   10622: );
                   10623: 
                   10624: /*
                   10625: ** CAPI3REF: Flags for sqlite3_deserialize()
                   10626: **
                   10627: ** The following are allowed values for 6th argument (the F argument) to
                   10628: ** the [sqlite3_deserialize(D,S,P,N,M,F)] interface.
                   10629: **
                   10630: ** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization
                   10631: ** in the P argument is held in memory obtained from [sqlite3_malloc64()]
                   10632: ** and that SQLite should take ownership of this memory and automatically
                   10633: ** free it when it has finished using it.  Without this flag, the caller
                   10634: ** is responsible for freeing any dynamically allocated memory.
                   10635: **
                   10636: ** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to
                   10637: ** grow the size of the database using calls to [sqlite3_realloc64()].  This
                   10638: ** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used.
                   10639: ** Without this flag, the deserialized database cannot increase in size beyond
                   10640: ** the number of bytes specified by the M parameter.
                   10641: **
                   10642: ** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database
                   10643: ** should be treated as read-only.
                   10644: */
                   10645: #define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */
                   10646: #define SQLITE_DESERIALIZE_RESIZEABLE  2 /* Resize using sqlite3_realloc64() */
                   10647: #define SQLITE_DESERIALIZE_READONLY    4 /* Database is read-only */
                   10648: 
                   10649: /*
1.2       misho    10650: ** Undo the hack that converts floating point types to integer for
                   10651: ** builds on processors without floating point support.
                   10652: */
                   10653: #ifdef SQLITE_OMIT_FLOATING_POINT
                   10654: # undef double
                   10655: #endif
                   10656: 
1.6.2.1 ! misho    10657: #if defined(__wasi__)
        !          10658: # undef SQLITE_WASI
        !          10659: # define SQLITE_WASI 1
        !          10660: # undef SQLITE_OMIT_WAL
        !          10661: # define SQLITE_OMIT_WAL 1/* because it requires shared memory APIs */
        !          10662: # ifndef SQLITE_OMIT_LOAD_EXTENSION
        !          10663: #  define SQLITE_OMIT_LOAD_EXTENSION
        !          10664: # endif
        !          10665: # ifndef SQLITE_THREADSAFE
        !          10666: #  define SQLITE_THREADSAFE 0
        !          10667: # endif
        !          10668: #endif
        !          10669: 
1.2       misho    10670: #ifdef __cplusplus
                   10671: }  /* End of the 'extern "C"' block */
                   10672: #endif
1.4       misho    10673: #endif /* SQLITE3_H */
1.2       misho    10674: 
1.4       misho    10675: /******** Begin file sqlite3rtree.h *********/
1.2       misho    10676: /*
                   10677: ** 2010 August 30
                   10678: **
                   10679: ** The author disclaims copyright to this source code.  In place of
                   10680: ** a legal notice, here is a blessing:
                   10681: **
                   10682: **    May you do good and not evil.
                   10683: **    May you find forgiveness for yourself and forgive others.
                   10684: **    May you share freely, never taking more than you give.
                   10685: **
                   10686: *************************************************************************
                   10687: */
                   10688: 
                   10689: #ifndef _SQLITE3RTREE_H_
                   10690: #define _SQLITE3RTREE_H_
                   10691: 
                   10692: 
                   10693: #ifdef __cplusplus
                   10694: extern "C" {
                   10695: #endif
                   10696: 
                   10697: typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
1.4       misho    10698: typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info;
                   10699: 
                   10700: /* The double-precision datatype used by RTree depends on the
                   10701: ** SQLITE_RTREE_INT_ONLY compile-time option.
                   10702: */
                   10703: #ifdef SQLITE_RTREE_INT_ONLY
                   10704:   typedef sqlite3_int64 sqlite3_rtree_dbl;
                   10705: #else
                   10706:   typedef double sqlite3_rtree_dbl;
                   10707: #endif
1.2       misho    10708: 
                   10709: /*
                   10710: ** Register a geometry callback named zGeom that can be used as part of an
                   10711: ** R-Tree geometry query as follows:
                   10712: **
                   10713: **   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
                   10714: */
                   10715: SQLITE_API int sqlite3_rtree_geometry_callback(
                   10716:   sqlite3 *db,
                   10717:   const char *zGeom,
1.4       misho    10718:   int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*),
1.2       misho    10719:   void *pContext
                   10720: );
                   10721: 
                   10722: 
                   10723: /*
                   10724: ** A pointer to a structure of the following type is passed as the first
                   10725: ** argument to callbacks registered using rtree_geometry_callback().
                   10726: */
                   10727: struct sqlite3_rtree_geometry {
                   10728:   void *pContext;                 /* Copy of pContext passed to s_r_g_c() */
                   10729:   int nParam;                     /* Size of array aParam[] */
1.4       misho    10730:   sqlite3_rtree_dbl *aParam;      /* Parameters passed to SQL geom function */
1.2       misho    10731:   void *pUser;                    /* Callback implementation user data */
                   10732:   void (*xDelUser)(void *);       /* Called by SQLite to clean up pUser */
                   10733: };
                   10734: 
1.4       misho    10735: /*
1.5       misho    10736: ** Register a 2nd-generation geometry callback named zScore that can be
1.4       misho    10737: ** used as part of an R-Tree geometry query as follows:
                   10738: **
                   10739: **   SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)
                   10740: */
                   10741: SQLITE_API int sqlite3_rtree_query_callback(
                   10742:   sqlite3 *db,
                   10743:   const char *zQueryFunc,
                   10744:   int (*xQueryFunc)(sqlite3_rtree_query_info*),
                   10745:   void *pContext,
                   10746:   void (*xDestructor)(void*)
                   10747: );
                   10748: 
                   10749: 
                   10750: /*
1.5       misho    10751: ** A pointer to a structure of the following type is passed as the
1.4       misho    10752: ** argument to scored geometry callback registered using
                   10753: ** sqlite3_rtree_query_callback().
                   10754: **
                   10755: ** Note that the first 5 fields of this structure are identical to
                   10756: ** sqlite3_rtree_geometry.  This structure is a subclass of
                   10757: ** sqlite3_rtree_geometry.
                   10758: */
                   10759: struct sqlite3_rtree_query_info {
                   10760:   void *pContext;                   /* pContext from when function registered */
                   10761:   int nParam;                       /* Number of function parameters */
                   10762:   sqlite3_rtree_dbl *aParam;        /* value of function parameters */
                   10763:   void *pUser;                      /* callback can use this, if desired */
                   10764:   void (*xDelUser)(void*);          /* function to free pUser */
                   10765:   sqlite3_rtree_dbl *aCoord;        /* Coordinates of node or entry to check */
                   10766:   unsigned int *anQueue;            /* Number of pending entries in the queue */
                   10767:   int nCoord;                       /* Number of coordinates */
                   10768:   int iLevel;                       /* Level of current node or entry */
                   10769:   int mxLevel;                      /* The largest iLevel value in the tree */
                   10770:   sqlite3_int64 iRowid;             /* Rowid for current entry */
                   10771:   sqlite3_rtree_dbl rParentScore;   /* Score of parent node */
                   10772:   int eParentWithin;                /* Visibility of parent node */
1.5       misho    10773:   int eWithin;                      /* OUT: Visibility */
1.4       misho    10774:   sqlite3_rtree_dbl rScore;         /* OUT: Write the score here */
                   10775:   /* The following fields are only available in 3.8.11 and later */
                   10776:   sqlite3_value **apSqlParam;       /* Original SQL values of parameters */
                   10777: };
                   10778: 
                   10779: /*
                   10780: ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.
                   10781: */
                   10782: #define NOT_WITHIN       0   /* Object completely outside of query region */
                   10783: #define PARTLY_WITHIN    1   /* Object partially overlaps query region */
                   10784: #define FULLY_WITHIN     2   /* Object fully contained within query region */
                   10785: 
1.2       misho    10786: 
                   10787: #ifdef __cplusplus
                   10788: }  /* end of the 'extern "C"' block */
                   10789: #endif
                   10790: 
                   10791: #endif  /* ifndef _SQLITE3RTREE_H_ */
                   10792: 
1.4       misho    10793: /******** End of sqlite3rtree.h *********/
                   10794: /******** Begin file sqlite3session.h *********/
                   10795: 
                   10796: #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)
                   10797: #define __SQLITESESSION_H_ 1
                   10798: 
                   10799: /*
                   10800: ** Make sure we can call this stuff from C++.
                   10801: */
                   10802: #ifdef __cplusplus
                   10803: extern "C" {
                   10804: #endif
                   10805: 
                   10806: 
                   10807: /*
                   10808: ** CAPI3REF: Session Object Handle
1.5       misho    10809: **
                   10810: ** An instance of this object is a [session] that can be used to
                   10811: ** record changes to a database.
1.4       misho    10812: */
                   10813: typedef struct sqlite3_session sqlite3_session;
                   10814: 
                   10815: /*
                   10816: ** CAPI3REF: Changeset Iterator Handle
1.5       misho    10817: **
                   10818: ** An instance of this object acts as a cursor for iterating
                   10819: ** over the elements of a [changeset] or [patchset].
1.4       misho    10820: */
                   10821: typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
                   10822: 
                   10823: /*
                   10824: ** CAPI3REF: Create A New Session Object
1.5       misho    10825: ** CONSTRUCTOR: sqlite3_session
1.4       misho    10826: **
                   10827: ** Create a new session object attached to database handle db. If successful,
                   10828: ** a pointer to the new object is written to *ppSession and SQLITE_OK is
                   10829: ** returned. If an error occurs, *ppSession is set to NULL and an SQLite
                   10830: ** error code (e.g. SQLITE_NOMEM) is returned.
                   10831: **
                   10832: ** It is possible to create multiple session objects attached to a single
                   10833: ** database handle.
                   10834: **
                   10835: ** Session objects created using this function should be deleted using the
                   10836: ** [sqlite3session_delete()] function before the database handle that they
                   10837: ** are attached to is itself closed. If the database handle is closed before
                   10838: ** the session object is deleted, then the results of calling any session
                   10839: ** module function, including [sqlite3session_delete()] on the session object
                   10840: ** are undefined.
                   10841: **
                   10842: ** Because the session module uses the [sqlite3_preupdate_hook()] API, it
                   10843: ** is not possible for an application to register a pre-update hook on a
                   10844: ** database handle that has one or more session objects attached. Nor is
                   10845: ** it possible to create a session object attached to a database handle for
1.5       misho    10846: ** which a pre-update hook is already defined. The results of attempting
1.4       misho    10847: ** either of these things are undefined.
                   10848: **
                   10849: ** The session object will be used to create changesets for tables in
                   10850: ** database zDb, where zDb is either "main", or "temp", or the name of an
                   10851: ** attached database. It is not an error if database zDb is not attached
                   10852: ** to the database when the session object is created.
                   10853: */
1.5       misho    10854: SQLITE_API int sqlite3session_create(
1.4       misho    10855:   sqlite3 *db,                    /* Database handle */
                   10856:   const char *zDb,                /* Name of db (e.g. "main") */
                   10857:   sqlite3_session **ppSession     /* OUT: New session object */
                   10858: );
                   10859: 
                   10860: /*
                   10861: ** CAPI3REF: Delete A Session Object
1.5       misho    10862: ** DESTRUCTOR: sqlite3_session
1.4       misho    10863: **
1.5       misho    10864: ** Delete a session object previously allocated using
1.4       misho    10865: ** [sqlite3session_create()]. Once a session object has been deleted, the
                   10866: ** results of attempting to use pSession with any other session module
                   10867: ** function are undefined.
                   10868: **
                   10869: ** Session objects must be deleted before the database handle to which they
1.5       misho    10870: ** are attached is closed. Refer to the documentation for
1.4       misho    10871: ** [sqlite3session_create()] for details.
                   10872: */
1.5       misho    10873: SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
1.4       misho    10874: 
1.6.2.1 ! misho    10875: /*
        !          10876: ** CAPI3REF: Configure a Session Object
        !          10877: ** METHOD: sqlite3_session
        !          10878: **
        !          10879: ** This method is used to configure a session object after it has been
        !          10880: ** created. At present the only valid values for the second parameter are
        !          10881: ** [SQLITE_SESSION_OBJCONFIG_SIZE] and [SQLITE_SESSION_OBJCONFIG_ROWID].
        !          10882: **
        !          10883: */
        !          10884: SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg);
        !          10885: 
        !          10886: /*
        !          10887: ** CAPI3REF: Options for sqlite3session_object_config
        !          10888: **
        !          10889: ** The following values may passed as the the 2nd parameter to
        !          10890: ** sqlite3session_object_config().
        !          10891: **
        !          10892: ** <dt>SQLITE_SESSION_OBJCONFIG_SIZE <dd>
        !          10893: **   This option is used to set, clear or query the flag that enables
        !          10894: **   the [sqlite3session_changeset_size()] API. Because it imposes some
        !          10895: **   computational overhead, this API is disabled by default. Argument
        !          10896: **   pArg must point to a value of type (int). If the value is initially
        !          10897: **   0, then the sqlite3session_changeset_size() API is disabled. If it
        !          10898: **   is greater than 0, then the same API is enabled. Or, if the initial
        !          10899: **   value is less than zero, no change is made. In all cases the (int)
        !          10900: **   variable is set to 1 if the sqlite3session_changeset_size() API is
        !          10901: **   enabled following the current call, or 0 otherwise.
        !          10902: **
        !          10903: **   It is an error (SQLITE_MISUSE) to attempt to modify this setting after
        !          10904: **   the first table has been attached to the session object.
        !          10905: **
        !          10906: ** <dt>SQLITE_SESSION_OBJCONFIG_ROWID <dd>
        !          10907: **   This option is used to set, clear or query the flag that enables
        !          10908: **   collection of data for tables with no explicit PRIMARY KEY.
        !          10909: **
        !          10910: **   Normally, tables with no explicit PRIMARY KEY are simply ignored
        !          10911: **   by the sessions module. However, if this flag is set, it behaves
        !          10912: **   as if such tables have a column "_rowid_ INTEGER PRIMARY KEY" inserted
        !          10913: **   as their leftmost columns.
        !          10914: **
        !          10915: **   It is an error (SQLITE_MISUSE) to attempt to modify this setting after
        !          10916: **   the first table has been attached to the session object.
        !          10917: */
        !          10918: #define SQLITE_SESSION_OBJCONFIG_SIZE  1
        !          10919: #define SQLITE_SESSION_OBJCONFIG_ROWID 2
1.4       misho    10920: 
                   10921: /*
                   10922: ** CAPI3REF: Enable Or Disable A Session Object
1.5       misho    10923: ** METHOD: sqlite3_session
1.4       misho    10924: **
                   10925: ** Enable or disable the recording of changes by a session object. When
                   10926: ** enabled, a session object records changes made to the database. When
                   10927: ** disabled - it does not. A newly created session object is enabled.
                   10928: ** Refer to the documentation for [sqlite3session_changeset()] for further
                   10929: ** details regarding how enabling and disabling a session object affects
                   10930: ** the eventual changesets.
                   10931: **
                   10932: ** Passing zero to this function disables the session. Passing a value
1.5       misho    10933: ** greater than zero enables it. Passing a value less than zero is a
1.4       misho    10934: ** no-op, and may be used to query the current state of the session.
                   10935: **
1.5       misho    10936: ** The return value indicates the final state of the session object: 0 if
1.4       misho    10937: ** the session is disabled, or 1 if it is enabled.
                   10938: */
1.5       misho    10939: SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable);
1.4       misho    10940: 
                   10941: /*
                   10942: ** CAPI3REF: Set Or Clear the Indirect Change Flag
1.5       misho    10943: ** METHOD: sqlite3_session
1.4       misho    10944: **
                   10945: ** Each change recorded by a session object is marked as either direct or
                   10946: ** indirect. A change is marked as indirect if either:
                   10947: **
                   10948: ** <ul>
                   10949: **   <li> The session object "indirect" flag is set when the change is
                   10950: **        made, or
1.5       misho    10951: **   <li> The change is made by an SQL trigger or foreign key action
1.4       misho    10952: **        instead of directly as a result of a users SQL statement.
                   10953: ** </ul>
                   10954: **
                   10955: ** If a single row is affected by more than one operation within a session,
                   10956: ** then the change is considered indirect if all operations meet the criteria
                   10957: ** for an indirect change above, or direct otherwise.
                   10958: **
                   10959: ** This function is used to set, clear or query the session object indirect
                   10960: ** flag.  If the second argument passed to this function is zero, then the
                   10961: ** indirect flag is cleared. If it is greater than zero, the indirect flag
                   10962: ** is set. Passing a value less than zero does not modify the current value
1.5       misho    10963: ** of the indirect flag, and may be used to query the current state of the
1.4       misho    10964: ** indirect flag for the specified session object.
                   10965: **
1.5       misho    10966: ** The return value indicates the final state of the indirect flag: 0 if
1.4       misho    10967: ** it is clear, or 1 if it is set.
                   10968: */
1.5       misho    10969: SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect);
1.4       misho    10970: 
                   10971: /*
                   10972: ** CAPI3REF: Attach A Table To A Session Object
1.5       misho    10973: ** METHOD: sqlite3_session
1.4       misho    10974: **
                   10975: ** If argument zTab is not NULL, then it is the name of a table to attach
1.5       misho    10976: ** to the session object passed as the first argument. All subsequent changes
                   10977: ** made to the table while the session object is enabled will be recorded. See
1.4       misho    10978: ** documentation for [sqlite3session_changeset()] for further details.
                   10979: **
                   10980: ** Or, if argument zTab is NULL, then changes are recorded for all tables
1.5       misho    10981: ** in the database. If additional tables are added to the database (by
                   10982: ** executing "CREATE TABLE" statements) after this call is made, changes for
1.4       misho    10983: ** the new tables are also recorded.
                   10984: **
                   10985: ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly
1.5       misho    10986: ** defined as part of their CREATE TABLE statement. It does not matter if the
1.4       misho    10987: ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY
                   10988: ** KEY may consist of a single column, or may be a composite key.
1.5       misho    10989: **
1.4       misho    10990: ** It is not an error if the named table does not exist in the database. Nor
                   10991: ** is it an error if the named table does not have a PRIMARY KEY. However,
                   10992: ** no changes will be recorded in either of these scenarios.
                   10993: **
                   10994: ** Changes are not recorded for individual rows that have NULL values stored
                   10995: ** in one or more of their PRIMARY KEY columns.
                   10996: **
1.5       misho    10997: ** SQLITE_OK is returned if the call completes without error. Or, if an error
1.4       misho    10998: ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
1.5       misho    10999: **
                   11000: ** <h3>Special sqlite_stat1 Handling</h3>
                   11001: **
                   11002: ** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to
                   11003: ** some of the rules above. In SQLite, the schema of sqlite_stat1 is:
                   11004: **  <pre>
                   11005: **  &nbsp;     CREATE TABLE sqlite_stat1(tbl,idx,stat)
                   11006: **  </pre>
                   11007: **
                   11008: ** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are
                   11009: ** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes
                   11010: ** are recorded for rows for which (idx IS NULL) is true. However, for such
                   11011: ** rows a zero-length blob (SQL value X'') is stored in the changeset or
                   11012: ** patchset instead of a NULL value. This allows such changesets to be
                   11013: ** manipulated by legacy implementations of sqlite3changeset_invert(),
                   11014: ** concat() and similar.
                   11015: **
                   11016: ** The sqlite3changeset_apply() function automatically converts the
                   11017: ** zero-length blob back to a NULL value when updating the sqlite_stat1
                   11018: ** table. However, if the application calls sqlite3changeset_new(),
                   11019: ** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset
                   11020: ** iterator directly (including on a changeset iterator passed to a
                   11021: ** conflict-handler callback) then the X'' value is returned. The application
                   11022: ** must translate X'' to NULL itself if required.
                   11023: **
                   11024: ** Legacy (older than 3.22.0) versions of the sessions module cannot capture
                   11025: ** changes made to the sqlite_stat1 table. Legacy versions of the
                   11026: ** sqlite3changeset_apply() function silently ignore any modifications to the
                   11027: ** sqlite_stat1 table that are part of a changeset or patchset.
1.4       misho    11028: */
1.5       misho    11029: SQLITE_API int sqlite3session_attach(
1.4       misho    11030:   sqlite3_session *pSession,      /* Session object */
                   11031:   const char *zTab                /* Table name */
                   11032: );
                   11033: 
                   11034: /*
                   11035: ** CAPI3REF: Set a table filter on a Session Object.
1.5       misho    11036: ** METHOD: sqlite3_session
1.4       misho    11037: **
1.5       misho    11038: ** The second argument (xFilter) is the "filter callback". For changes to rows
                   11039: ** in tables that are not attached to the Session object, the filter is called
                   11040: ** to determine whether changes to the table's rows should be tracked or not.
                   11041: ** If xFilter returns 0, changes are not tracked. Note that once a table is
1.4       misho    11042: ** attached, xFilter will not be called again.
                   11043: */
1.5       misho    11044: SQLITE_API void sqlite3session_table_filter(
1.4       misho    11045:   sqlite3_session *pSession,      /* Session object */
                   11046:   int(*xFilter)(
                   11047:     void *pCtx,                   /* Copy of third arg to _filter_table() */
                   11048:     const char *zTab              /* Table name */
                   11049:   ),
                   11050:   void *pCtx                      /* First argument passed to xFilter */
                   11051: );
                   11052: 
                   11053: /*
                   11054: ** CAPI3REF: Generate A Changeset From A Session Object
1.5       misho    11055: ** METHOD: sqlite3_session
1.4       misho    11056: **
1.5       misho    11057: ** Obtain a changeset containing changes to the tables attached to the
                   11058: ** session object passed as the first argument. If successful,
                   11059: ** set *ppChangeset to point to a buffer containing the changeset
1.4       misho    11060: ** and *pnChangeset to the size of the changeset in bytes before returning
                   11061: ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to
                   11062: ** zero and return an SQLite error code.
                   11063: **
                   11064: ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,
                   11065: ** each representing a change to a single row of an attached table. An INSERT
                   11066: ** change contains the values of each field of a new database row. A DELETE
                   11067: ** contains the original values of each field of a deleted database row. An
                   11068: ** UPDATE change contains the original values of each field of an updated
                   11069: ** database row along with the updated values for each updated non-primary-key
                   11070: ** column. It is not possible for an UPDATE change to represent a change that
                   11071: ** modifies the values of primary key columns. If such a change is made, it
                   11072: ** is represented in a changeset as a DELETE followed by an INSERT.
                   11073: **
1.5       misho    11074: ** Changes are not recorded for rows that have NULL values stored in one or
1.4       misho    11075: ** more of their PRIMARY KEY columns. If such a row is inserted or deleted,
                   11076: ** no corresponding change is present in the changesets returned by this
                   11077: ** function. If an existing row with one or more NULL values stored in
                   11078: ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,
                   11079: ** only an INSERT is appears in the changeset. Similarly, if an existing row
                   11080: ** with non-NULL PRIMARY KEY values is updated so that one or more of its
                   11081: ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a
                   11082: ** DELETE change only.
                   11083: **
                   11084: ** The contents of a changeset may be traversed using an iterator created
                   11085: ** using the [sqlite3changeset_start()] API. A changeset may be applied to
                   11086: ** a database with a compatible schema using the [sqlite3changeset_apply()]
                   11087: ** API.
                   11088: **
                   11089: ** Within a changeset generated by this function, all changes related to a
                   11090: ** single table are grouped together. In other words, when iterating through
                   11091: ** a changeset or when applying a changeset to a database, all changes related
                   11092: ** to a single table are processed before moving on to the next table. Tables
                   11093: ** are sorted in the same order in which they were attached (or auto-attached)
                   11094: ** to the sqlite3_session object. The order in which the changes related to
                   11095: ** a single table are stored is undefined.
                   11096: **
                   11097: ** Following a successful call to this function, it is the responsibility of
                   11098: ** the caller to eventually free the buffer that *ppChangeset points to using
                   11099: ** [sqlite3_free()].
                   11100: **
                   11101: ** <h3>Changeset Generation</h3>
                   11102: **
                   11103: ** Once a table has been attached to a session object, the session object
                   11104: ** records the primary key values of all new rows inserted into the table.
                   11105: ** It also records the original primary key and other column values of any
                   11106: ** deleted or updated rows. For each unique primary key value, data is only
                   11107: ** recorded once - the first time a row with said primary key is inserted,
                   11108: ** updated or deleted in the lifetime of the session.
                   11109: **
                   11110: ** There is one exception to the previous paragraph: when a row is inserted,
                   11111: ** updated or deleted, if one or more of its primary key columns contain a
                   11112: ** NULL value, no record of the change is made.
                   11113: **
                   11114: ** The session object therefore accumulates two types of records - those
                   11115: ** that consist of primary key values only (created when the user inserts
                   11116: ** a new record) and those that consist of the primary key values and the
                   11117: ** original values of other table columns (created when the users deletes
                   11118: ** or updates a record).
                   11119: **
                   11120: ** When this function is called, the requested changeset is created using
                   11121: ** both the accumulated records and the current contents of the database
                   11122: ** file. Specifically:
                   11123: **
                   11124: ** <ul>
                   11125: **   <li> For each record generated by an insert, the database is queried
                   11126: **        for a row with a matching primary key. If one is found, an INSERT
1.5       misho    11127: **        change is added to the changeset. If no such row is found, no change
1.4       misho    11128: **        is added to the changeset.
                   11129: **
1.5       misho    11130: **   <li> For each record generated by an update or delete, the database is
1.4       misho    11131: **        queried for a row with a matching primary key. If such a row is
                   11132: **        found and one or more of the non-primary key fields have been
1.5       misho    11133: **        modified from their original values, an UPDATE change is added to
                   11134: **        the changeset. Or, if no such row is found in the table, a DELETE
1.4       misho    11135: **        change is added to the changeset. If there is a row with a matching
                   11136: **        primary key in the database, but all fields contain their original
                   11137: **        values, no change is added to the changeset.
                   11138: ** </ul>
                   11139: **
                   11140: ** This means, amongst other things, that if a row is inserted and then later
                   11141: ** deleted while a session object is active, neither the insert nor the delete
1.5       misho    11142: ** will be present in the changeset. Or if a row is deleted and then later a
1.4       misho    11143: ** row with the same primary key values inserted while a session object is
                   11144: ** active, the resulting changeset will contain an UPDATE change instead of
                   11145: ** a DELETE and an INSERT.
                   11146: **
                   11147: ** When a session object is disabled (see the [sqlite3session_enable()] API),
                   11148: ** it does not accumulate records when rows are inserted, updated or deleted.
                   11149: ** This may appear to have some counter-intuitive effects if a single row
                   11150: ** is written to more than once during a session. For example, if a row
1.5       misho    11151: ** is inserted while a session object is enabled, then later deleted while
1.4       misho    11152: ** the same session object is disabled, no INSERT record will appear in the
                   11153: ** changeset, even though the delete took place while the session was disabled.
1.5       misho    11154: ** Or, if one field of a row is updated while a session is disabled, and
1.4       misho    11155: ** another field of the same row is updated while the session is enabled, the
                   11156: ** resulting changeset will contain an UPDATE change that updates both fields.
                   11157: */
1.5       misho    11158: SQLITE_API int sqlite3session_changeset(
1.4       misho    11159:   sqlite3_session *pSession,      /* Session object */
                   11160:   int *pnChangeset,               /* OUT: Size of buffer at *ppChangeset */
                   11161:   void **ppChangeset              /* OUT: Buffer containing changeset */
                   11162: );
                   11163: 
                   11164: /*
1.6.2.1 ! misho    11165: ** CAPI3REF: Return An Upper-limit For The Size Of The Changeset
        !          11166: ** METHOD: sqlite3_session
        !          11167: **
        !          11168: ** By default, this function always returns 0. For it to return
        !          11169: ** a useful result, the sqlite3_session object must have been configured
        !          11170: ** to enable this API using sqlite3session_object_config() with the
        !          11171: ** SQLITE_SESSION_OBJCONFIG_SIZE verb.
        !          11172: **
        !          11173: ** When enabled, this function returns an upper limit, in bytes, for the size
        !          11174: ** of the changeset that might be produced if sqlite3session_changeset() were
        !          11175: ** called. The final changeset size might be equal to or smaller than the
        !          11176: ** size in bytes returned by this function.
        !          11177: */
        !          11178: SQLITE_API sqlite3_int64 sqlite3session_changeset_size(sqlite3_session *pSession);
        !          11179: 
        !          11180: /*
1.5       misho    11181: ** CAPI3REF: Load The Difference Between Tables Into A Session
                   11182: ** METHOD: sqlite3_session
1.4       misho    11183: **
                   11184: ** If it is not already attached to the session object passed as the first
                   11185: ** argument, this function attaches table zTbl in the same manner as the
                   11186: ** [sqlite3session_attach()] function. If zTbl does not exist, or if it
                   11187: ** does not have a primary key, this function is a no-op (but does not return
                   11188: ** an error).
                   11189: **
                   11190: ** Argument zFromDb must be the name of a database ("main", "temp" etc.)
1.5       misho    11191: ** attached to the same database handle as the session object that contains
1.4       misho    11192: ** a table compatible with the table attached to the session by this function.
                   11193: ** A table is considered compatible if it:
                   11194: **
                   11195: ** <ul>
                   11196: **   <li> Has the same name,
                   11197: **   <li> Has the same set of columns declared in the same order, and
                   11198: **   <li> Has the same PRIMARY KEY definition.
                   11199: ** </ul>
                   11200: **
                   11201: ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables
                   11202: ** are compatible but do not have any PRIMARY KEY columns, it is not an error
                   11203: ** but no changes are added to the session object. As with other session
                   11204: ** APIs, tables without PRIMARY KEYs are simply ignored.
                   11205: **
                   11206: ** This function adds a set of changes to the session object that could be
1.5       misho    11207: ** used to update the table in database zFrom (call this the "from-table")
                   11208: ** so that its content is the same as the table attached to the session
1.4       misho    11209: ** object (call this the "to-table"). Specifically:
                   11210: **
                   11211: ** <ul>
1.5       misho    11212: **   <li> For each row (primary key) that exists in the to-table but not in
1.4       misho    11213: **     the from-table, an INSERT record is added to the session object.
                   11214: **
1.5       misho    11215: **   <li> For each row (primary key) that exists in the to-table but not in
1.4       misho    11216: **     the from-table, a DELETE record is added to the session object.
                   11217: **
1.5       misho    11218: **   <li> For each row (primary key) that exists in both tables, but features
                   11219: **     different non-PK values in each, an UPDATE record is added to the
                   11220: **     session.
1.4       misho    11221: ** </ul>
                   11222: **
                   11223: ** To clarify, if this function is called and then a changeset constructed
1.5       misho    11224: ** using [sqlite3session_changeset()], then after applying that changeset to
                   11225: ** database zFrom the contents of the two compatible tables would be
1.4       misho    11226: ** identical.
                   11227: **
                   11228: ** It an error if database zFrom does not exist or does not contain the
                   11229: ** required compatible table.
                   11230: **
1.5       misho    11231: ** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite
1.4       misho    11232: ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg
1.5       misho    11233: ** may be set to point to a buffer containing an English language error
1.4       misho    11234: ** message. It is the responsibility of the caller to free this buffer using
                   11235: ** sqlite3_free().
                   11236: */
1.5       misho    11237: SQLITE_API int sqlite3session_diff(
1.4       misho    11238:   sqlite3_session *pSession,
                   11239:   const char *zFromDb,
                   11240:   const char *zTbl,
                   11241:   char **pzErrMsg
                   11242: );
                   11243: 
                   11244: 
                   11245: /*
                   11246: ** CAPI3REF: Generate A Patchset From A Session Object
1.5       misho    11247: ** METHOD: sqlite3_session
1.4       misho    11248: **
                   11249: ** The differences between a patchset and a changeset are that:
                   11250: **
                   11251: ** <ul>
1.5       misho    11252: **   <li> DELETE records consist of the primary key fields only. The
1.4       misho    11253: **        original values of other fields are omitted.
1.5       misho    11254: **   <li> The original values of any modified fields are omitted from
1.4       misho    11255: **        UPDATE records.
                   11256: ** </ul>
                   11257: **
1.5       misho    11258: ** A patchset blob may be used with up to date versions of all
                   11259: ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(),
1.4       misho    11260: ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,
                   11261: ** attempting to use a patchset blob with old versions of the
1.5       misho    11262: ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error.
1.4       misho    11263: **
1.5       misho    11264: ** Because the non-primary key "old.*" fields are omitted, no
1.4       misho    11265: ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset
                   11266: ** is passed to the sqlite3changeset_apply() API. Other conflict types work
                   11267: ** in the same way as for changesets.
                   11268: **
                   11269: ** Changes within a patchset are ordered in the same way as for changesets
                   11270: ** generated by the sqlite3session_changeset() function (i.e. all changes for
                   11271: ** a single table are grouped together, tables appear in the order in which
                   11272: ** they were attached to the session object).
                   11273: */
1.5       misho    11274: SQLITE_API int sqlite3session_patchset(
1.4       misho    11275:   sqlite3_session *pSession,      /* Session object */
1.5       misho    11276:   int *pnPatchset,                /* OUT: Size of buffer at *ppPatchset */
                   11277:   void **ppPatchset               /* OUT: Buffer containing patchset */
1.4       misho    11278: );
                   11279: 
                   11280: /*
                   11281: ** CAPI3REF: Test if a changeset has recorded any changes.
                   11282: **
1.5       misho    11283: ** Return non-zero if no changes to attached tables have been recorded by
                   11284: ** the session object passed as the first argument. Otherwise, if one or
1.4       misho    11285: ** more changes have been recorded, return zero.
                   11286: **
                   11287: ** Even if this function returns zero, it is possible that calling
                   11288: ** [sqlite3session_changeset()] on the session handle may still return a
1.5       misho    11289: ** changeset that contains no changes. This can happen when a row in
                   11290: ** an attached table is modified and then later on the original values
1.4       misho    11291: ** are restored. However, if this function returns non-zero, then it is
1.5       misho    11292: ** guaranteed that a call to sqlite3session_changeset() will return a
1.4       misho    11293: ** changeset containing zero changes.
                   11294: */
1.5       misho    11295: SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession);
1.4       misho    11296: 
                   11297: /*
1.6       misho    11298: ** CAPI3REF: Query for the amount of heap memory used by a session object.
                   11299: **
                   11300: ** This API returns the total amount of heap memory in bytes currently
                   11301: ** used by the session object passed as the only argument.
                   11302: */
                   11303: SQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession);
                   11304: 
                   11305: /*
1.5       misho    11306: ** CAPI3REF: Create An Iterator To Traverse A Changeset
                   11307: ** CONSTRUCTOR: sqlite3_changeset_iter
1.4       misho    11308: **
                   11309: ** Create an iterator used to iterate through the contents of a changeset.
                   11310: ** If successful, *pp is set to point to the iterator handle and SQLITE_OK
                   11311: ** is returned. Otherwise, if an error occurs, *pp is set to zero and an
                   11312: ** SQLite error code is returned.
                   11313: **
1.5       misho    11314: ** The following functions can be used to advance and query a changeset
1.4       misho    11315: ** iterator created by this function:
                   11316: **
                   11317: ** <ul>
                   11318: **   <li> [sqlite3changeset_next()]
                   11319: **   <li> [sqlite3changeset_op()]
                   11320: **   <li> [sqlite3changeset_new()]
                   11321: **   <li> [sqlite3changeset_old()]
                   11322: ** </ul>
                   11323: **
                   11324: ** It is the responsibility of the caller to eventually destroy the iterator
                   11325: ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the
                   11326: ** changeset (pChangeset) must remain valid until after the iterator is
                   11327: ** destroyed.
                   11328: **
                   11329: ** Assuming the changeset blob was created by one of the
                   11330: ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or
1.5       misho    11331: ** [sqlite3changeset_invert()] functions, all changes within the changeset
                   11332: ** that apply to a single table are grouped together. This means that when
                   11333: ** an application iterates through a changeset using an iterator created by
                   11334: ** this function, all changes that relate to a single table are visited
                   11335: ** consecutively. There is no chance that the iterator will visit a change
                   11336: ** the applies to table X, then one for table Y, and then later on visit
1.4       misho    11337: ** another change for table X.
1.5       misho    11338: **
                   11339: ** The behavior of sqlite3changeset_start_v2() and its streaming equivalent
                   11340: ** may be modified by passing a combination of
                   11341: ** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter.
                   11342: **
                   11343: ** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b>
                   11344: ** and therefore subject to change.
1.4       misho    11345: */
1.5       misho    11346: SQLITE_API int sqlite3changeset_start(
1.4       misho    11347:   sqlite3_changeset_iter **pp,    /* OUT: New changeset iterator handle */
                   11348:   int nChangeset,                 /* Size of changeset blob in bytes */
                   11349:   void *pChangeset                /* Pointer to blob containing changeset */
                   11350: );
1.5       misho    11351: SQLITE_API int sqlite3changeset_start_v2(
                   11352:   sqlite3_changeset_iter **pp,    /* OUT: New changeset iterator handle */
                   11353:   int nChangeset,                 /* Size of changeset blob in bytes */
                   11354:   void *pChangeset,               /* Pointer to blob containing changeset */
                   11355:   int flags                       /* SESSION_CHANGESETSTART_* flags */
                   11356: );
                   11357: 
                   11358: /*
                   11359: ** CAPI3REF: Flags for sqlite3changeset_start_v2
                   11360: **
                   11361: ** The following flags may passed via the 4th parameter to
                   11362: ** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]:
                   11363: **
                   11364: ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
                   11365: **   Invert the changeset while iterating through it. This is equivalent to
                   11366: **   inverting a changeset using sqlite3changeset_invert() before applying it.
                   11367: **   It is an error to specify this flag with a patchset.
                   11368: */
                   11369: #define SQLITE_CHANGESETSTART_INVERT        0x0002
1.4       misho    11370: 
                   11371: 
                   11372: /*
                   11373: ** CAPI3REF: Advance A Changeset Iterator
1.5       misho    11374: ** METHOD: sqlite3_changeset_iter
1.4       misho    11375: **
1.5       misho    11376: ** This function may only be used with iterators created by the function
1.4       misho    11377: ** [sqlite3changeset_start()]. If it is called on an iterator passed to
                   11378: ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE
                   11379: ** is returned and the call has no effect.
                   11380: **
                   11381: ** Immediately after an iterator is created by sqlite3changeset_start(), it
                   11382: ** does not point to any change in the changeset. Assuming the changeset
                   11383: ** is not empty, the first call to this function advances the iterator to
                   11384: ** point to the first change in the changeset. Each subsequent call advances
                   11385: ** the iterator to point to the next change in the changeset (if any). If
                   11386: ** no error occurs and the iterator points to a valid change after a call
1.5       misho    11387: ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned.
1.4       misho    11388: ** Otherwise, if all changes in the changeset have already been visited,
                   11389: ** SQLITE_DONE is returned.
                   11390: **
1.5       misho    11391: ** If an error occurs, an SQLite error code is returned. Possible error
                   11392: ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or
1.4       misho    11393: ** SQLITE_NOMEM.
                   11394: */
1.5       misho    11395: SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter);
1.4       misho    11396: 
                   11397: /*
                   11398: ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator
1.5       misho    11399: ** METHOD: sqlite3_changeset_iter
1.4       misho    11400: **
                   11401: ** The pIter argument passed to this function may either be an iterator
                   11402: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
                   11403: ** created by [sqlite3changeset_start()]. In the latter case, the most recent
                   11404: ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this
                   11405: ** is not the case, this function returns [SQLITE_MISUSE].
                   11406: **
1.6       misho    11407: ** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three
                   11408: ** outputs are set through these pointers:
                   11409: **
                   11410: ** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE],
                   11411: ** depending on the type of change that the iterator currently points to;
                   11412: **
                   11413: ** *pnCol is set to the number of columns in the table affected by the change; and
                   11414: **
                   11415: ** *pzTab is set to point to a nul-terminated utf-8 encoded string containing
                   11416: ** the name of the table affected by the current change. The buffer remains
                   11417: ** valid until either sqlite3changeset_next() is called on the iterator
                   11418: ** or until the conflict-handler function returns.
                   11419: **
                   11420: ** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change
1.4       misho    11421: ** is an indirect change, or false (0) otherwise. See the documentation for
                   11422: ** [sqlite3session_indirect()] for a description of direct and indirect
1.6       misho    11423: ** changes.
1.4       misho    11424: **
                   11425: ** If no error occurs, SQLITE_OK is returned. If an error does occur, an
                   11426: ** SQLite error code is returned. The values of the output variables may not
                   11427: ** be trusted in this case.
                   11428: */
1.5       misho    11429: SQLITE_API int sqlite3changeset_op(
1.4       misho    11430:   sqlite3_changeset_iter *pIter,  /* Iterator object */
                   11431:   const char **pzTab,             /* OUT: Pointer to table name */
                   11432:   int *pnCol,                     /* OUT: Number of columns in table */
                   11433:   int *pOp,                       /* OUT: SQLITE_INSERT, DELETE or UPDATE */
                   11434:   int *pbIndirect                 /* OUT: True for an 'indirect' change */
                   11435: );
                   11436: 
                   11437: /*
                   11438: ** CAPI3REF: Obtain The Primary Key Definition Of A Table
1.5       misho    11439: ** METHOD: sqlite3_changeset_iter
1.4       misho    11440: **
                   11441: ** For each modified table, a changeset includes the following:
                   11442: **
                   11443: ** <ul>
                   11444: **   <li> The number of columns in the table, and
                   11445: **   <li> Which of those columns make up the tables PRIMARY KEY.
                   11446: ** </ul>
                   11447: **
                   11448: ** This function is used to find which columns comprise the PRIMARY KEY of
                   11449: ** the table modified by the change that iterator pIter currently points to.
                   11450: ** If successful, *pabPK is set to point to an array of nCol entries, where
                   11451: ** nCol is the number of columns in the table. Elements of *pabPK are set to
                   11452: ** 0x01 if the corresponding column is part of the tables primary key, or
                   11453: ** 0x00 if it is not.
                   11454: **
1.5       misho    11455: ** If argument pnCol is not NULL, then *pnCol is set to the number of columns
1.4       misho    11456: ** in the table.
                   11457: **
                   11458: ** If this function is called when the iterator does not point to a valid
                   11459: ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,
                   11460: ** SQLITE_OK is returned and the output variables populated as described
                   11461: ** above.
                   11462: */
1.5       misho    11463: SQLITE_API int sqlite3changeset_pk(
1.4       misho    11464:   sqlite3_changeset_iter *pIter,  /* Iterator object */
                   11465:   unsigned char **pabPK,          /* OUT: Array of boolean - true for PK cols */
                   11466:   int *pnCol                      /* OUT: Number of entries in output array */
                   11467: );
                   11468: 
                   11469: /*
                   11470: ** CAPI3REF: Obtain old.* Values From A Changeset Iterator
1.5       misho    11471: ** METHOD: sqlite3_changeset_iter
1.4       misho    11472: **
                   11473: ** The pIter argument passed to this function may either be an iterator
                   11474: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
                   11475: ** created by [sqlite3changeset_start()]. In the latter case, the most recent
1.5       misho    11476: ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
1.4       misho    11477: ** Furthermore, it may only be called if the type of change that the iterator
                   11478: ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,
                   11479: ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
                   11480: **
                   11481: ** Argument iVal must be greater than or equal to 0, and less than the number
                   11482: ** of columns in the table affected by the current change. Otherwise,
                   11483: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
                   11484: **
                   11485: ** If successful, this function sets *ppValue to point to a protected
1.5       misho    11486: ** sqlite3_value object containing the iVal'th value from the vector of
1.4       misho    11487: ** original row values stored as part of the UPDATE or DELETE change and
1.5       misho    11488: ** returns SQLITE_OK. The name of the function comes from the fact that this
1.4       misho    11489: ** is similar to the "old.*" columns available to update or delete triggers.
                   11490: **
                   11491: ** If some other error occurs (e.g. an OOM condition), an SQLite error code
                   11492: ** is returned and *ppValue is set to NULL.
                   11493: */
1.5       misho    11494: SQLITE_API int sqlite3changeset_old(
1.4       misho    11495:   sqlite3_changeset_iter *pIter,  /* Changeset iterator */
                   11496:   int iVal,                       /* Column number */
                   11497:   sqlite3_value **ppValue         /* OUT: Old value (or NULL pointer) */
                   11498: );
                   11499: 
                   11500: /*
                   11501: ** CAPI3REF: Obtain new.* Values From A Changeset Iterator
1.5       misho    11502: ** METHOD: sqlite3_changeset_iter
1.4       misho    11503: **
                   11504: ** The pIter argument passed to this function may either be an iterator
                   11505: ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator
                   11506: ** created by [sqlite3changeset_start()]. In the latter case, the most recent
1.5       misho    11507: ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW.
1.4       misho    11508: ** Furthermore, it may only be called if the type of change that the iterator
                   11509: ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,
                   11510: ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.
                   11511: **
                   11512: ** Argument iVal must be greater than or equal to 0, and less than the number
                   11513: ** of columns in the table affected by the current change. Otherwise,
                   11514: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
                   11515: **
                   11516: ** If successful, this function sets *ppValue to point to a protected
1.5       misho    11517: ** sqlite3_value object containing the iVal'th value from the vector of
1.4       misho    11518: ** new row values stored as part of the UPDATE or INSERT change and
                   11519: ** returns SQLITE_OK. If the change is an UPDATE and does not include
1.5       misho    11520: ** a new value for the requested column, *ppValue is set to NULL and
                   11521: ** SQLITE_OK returned. The name of the function comes from the fact that
                   11522: ** this is similar to the "new.*" columns available to update or delete
1.4       misho    11523: ** triggers.
                   11524: **
                   11525: ** If some other error occurs (e.g. an OOM condition), an SQLite error code
                   11526: ** is returned and *ppValue is set to NULL.
                   11527: */
1.5       misho    11528: SQLITE_API int sqlite3changeset_new(
1.4       misho    11529:   sqlite3_changeset_iter *pIter,  /* Changeset iterator */
                   11530:   int iVal,                       /* Column number */
                   11531:   sqlite3_value **ppValue         /* OUT: New value (or NULL pointer) */
                   11532: );
                   11533: 
                   11534: /*
                   11535: ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator
1.5       misho    11536: ** METHOD: sqlite3_changeset_iter
1.4       misho    11537: **
                   11538: ** This function should only be used with iterator objects passed to a
                   11539: ** conflict-handler callback by [sqlite3changeset_apply()] with either
                   11540: ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function
                   11541: ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue
                   11542: ** is set to NULL.
                   11543: **
                   11544: ** Argument iVal must be greater than or equal to 0, and less than the number
                   11545: ** of columns in the table affected by the current change. Otherwise,
                   11546: ** [SQLITE_RANGE] is returned and *ppValue is set to NULL.
                   11547: **
                   11548: ** If successful, this function sets *ppValue to point to a protected
1.5       misho    11549: ** sqlite3_value object containing the iVal'th value from the
1.4       misho    11550: ** "conflicting row" associated with the current conflict-handler callback
                   11551: ** and returns SQLITE_OK.
                   11552: **
                   11553: ** If some other error occurs (e.g. an OOM condition), an SQLite error code
                   11554: ** is returned and *ppValue is set to NULL.
                   11555: */
1.5       misho    11556: SQLITE_API int sqlite3changeset_conflict(
1.4       misho    11557:   sqlite3_changeset_iter *pIter,  /* Changeset iterator */
                   11558:   int iVal,                       /* Column number */
                   11559:   sqlite3_value **ppValue         /* OUT: Value from conflicting row */
                   11560: );
                   11561: 
                   11562: /*
                   11563: ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations
1.5       misho    11564: ** METHOD: sqlite3_changeset_iter
1.4       misho    11565: **
                   11566: ** This function may only be called with an iterator passed to an
                   11567: ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case
                   11568: ** it sets the output variable to the total number of known foreign key
                   11569: ** violations in the destination database and returns SQLITE_OK.
                   11570: **
                   11571: ** In all other cases this function returns SQLITE_MISUSE.
                   11572: */
1.5       misho    11573: SQLITE_API int sqlite3changeset_fk_conflicts(
1.4       misho    11574:   sqlite3_changeset_iter *pIter,  /* Changeset iterator */
                   11575:   int *pnOut                      /* OUT: Number of FK violations */
                   11576: );
                   11577: 
                   11578: 
                   11579: /*
                   11580: ** CAPI3REF: Finalize A Changeset Iterator
1.5       misho    11581: ** METHOD: sqlite3_changeset_iter
1.4       misho    11582: **
                   11583: ** This function is used to finalize an iterator allocated with
                   11584: ** [sqlite3changeset_start()].
                   11585: **
                   11586: ** This function should only be called on iterators created using the
                   11587: ** [sqlite3changeset_start()] function. If an application calls this
                   11588: ** function with an iterator passed to a conflict-handler by
                   11589: ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the
                   11590: ** call has no effect.
                   11591: **
                   11592: ** If an error was encountered within a call to an sqlite3changeset_xxx()
1.5       misho    11593: ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an
1.4       misho    11594: ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding
                   11595: ** to that error is returned by this function. Otherwise, SQLITE_OK is
                   11596: ** returned. This is to allow the following pattern (pseudo-code):
                   11597: **
1.5       misho    11598: ** <pre>
1.4       misho    11599: **   sqlite3changeset_start();
                   11600: **   while( SQLITE_ROW==sqlite3changeset_next() ){
                   11601: **     // Do something with change.
                   11602: **   }
                   11603: **   rc = sqlite3changeset_finalize();
                   11604: **   if( rc!=SQLITE_OK ){
1.5       misho    11605: **     // An error has occurred
1.4       misho    11606: **   }
1.5       misho    11607: ** </pre>
1.4       misho    11608: */
1.5       misho    11609: SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter);
1.4       misho    11610: 
                   11611: /*
                   11612: ** CAPI3REF: Invert A Changeset
                   11613: **
                   11614: ** This function is used to "invert" a changeset object. Applying an inverted
                   11615: ** changeset to a database reverses the effects of applying the uninverted
                   11616: ** changeset. Specifically:
                   11617: **
                   11618: ** <ul>
                   11619: **   <li> Each DELETE change is changed to an INSERT, and
                   11620: **   <li> Each INSERT change is changed to a DELETE, and
                   11621: **   <li> For each UPDATE change, the old.* and new.* values are exchanged.
                   11622: ** </ul>
                   11623: **
                   11624: ** This function does not change the order in which changes appear within
                   11625: ** the changeset. It merely reverses the sense of each individual change.
                   11626: **
                   11627: ** If successful, a pointer to a buffer containing the inverted changeset
                   11628: ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and
                   11629: ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are
                   11630: ** zeroed and an SQLite error code returned.
                   11631: **
                   11632: ** It is the responsibility of the caller to eventually call sqlite3_free()
1.5       misho    11633: ** on the *ppOut pointer to free the buffer allocation following a successful
1.4       misho    11634: ** call to this function.
                   11635: **
                   11636: ** WARNING/TODO: This function currently assumes that the input is a valid
                   11637: ** changeset. If it is not, the results are undefined.
                   11638: */
1.5       misho    11639: SQLITE_API int sqlite3changeset_invert(
1.4       misho    11640:   int nIn, const void *pIn,       /* Input changeset */
                   11641:   int *pnOut, void **ppOut        /* OUT: Inverse of input */
                   11642: );
                   11643: 
                   11644: /*
                   11645: ** CAPI3REF: Concatenate Two Changeset Objects
                   11646: **
1.5       misho    11647: ** This function is used to concatenate two changesets, A and B, into a
1.4       misho    11648: ** single changeset. The result is a changeset equivalent to applying
1.5       misho    11649: ** changeset A followed by changeset B.
1.4       misho    11650: **
1.5       misho    11651: ** This function combines the two input changesets using an
1.4       misho    11652: ** sqlite3_changegroup object. Calling it produces similar results as the
                   11653: ** following code fragment:
                   11654: **
1.5       misho    11655: ** <pre>
1.4       misho    11656: **   sqlite3_changegroup *pGrp;
                   11657: **   rc = sqlite3_changegroup_new(&pGrp);
                   11658: **   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);
                   11659: **   if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);
                   11660: **   if( rc==SQLITE_OK ){
                   11661: **     rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);
                   11662: **   }else{
                   11663: **     *ppOut = 0;
                   11664: **     *pnOut = 0;
                   11665: **   }
1.5       misho    11666: ** </pre>
1.4       misho    11667: **
                   11668: ** Refer to the sqlite3_changegroup documentation below for details.
                   11669: */
1.5       misho    11670: SQLITE_API int sqlite3changeset_concat(
1.4       misho    11671:   int nA,                         /* Number of bytes in buffer pA */
                   11672:   void *pA,                       /* Pointer to buffer containing changeset A */
                   11673:   int nB,                         /* Number of bytes in buffer pB */
                   11674:   void *pB,                       /* Pointer to buffer containing changeset B */
                   11675:   int *pnOut,                     /* OUT: Number of bytes in output changeset */
                   11676:   void **ppOut                    /* OUT: Buffer containing output changeset */
                   11677: );
                   11678: 
                   11679: 
                   11680: /*
1.5       misho    11681: ** CAPI3REF: Changegroup Handle
                   11682: **
                   11683: ** A changegroup is an object used to combine two or more
                   11684: ** [changesets] or [patchsets]
1.4       misho    11685: */
                   11686: typedef struct sqlite3_changegroup sqlite3_changegroup;
                   11687: 
                   11688: /*
1.5       misho    11689: ** CAPI3REF: Create A New Changegroup Object
                   11690: ** CONSTRUCTOR: sqlite3_changegroup
1.4       misho    11691: **
                   11692: ** An sqlite3_changegroup object is used to combine two or more changesets
                   11693: ** (or patchsets) into a single changeset (or patchset). A single changegroup
                   11694: ** object may combine changesets or patchsets, but not both. The output is
                   11695: ** always in the same format as the input.
                   11696: **
                   11697: ** If successful, this function returns SQLITE_OK and populates (*pp) with
                   11698: ** a pointer to a new sqlite3_changegroup object before returning. The caller
1.5       misho    11699: ** should eventually free the returned object using a call to
1.4       misho    11700: ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code
                   11701: ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.
                   11702: **
                   11703: ** The usual usage pattern for an sqlite3_changegroup object is as follows:
                   11704: **
                   11705: ** <ul>
                   11706: **   <li> It is created using a call to sqlite3changegroup_new().
                   11707: **
                   11708: **   <li> Zero or more changesets (or patchsets) are added to the object
                   11709: **        by calling sqlite3changegroup_add().
                   11710: **
1.5       misho    11711: **   <li> The result of combining all input changesets together is obtained
1.4       misho    11712: **        by the application via a call to sqlite3changegroup_output().
                   11713: **
                   11714: **   <li> The object is deleted using a call to sqlite3changegroup_delete().
                   11715: ** </ul>
                   11716: **
                   11717: ** Any number of calls to add() and output() may be made between the calls to
                   11718: ** new() and delete(), and in any order.
                   11719: **
1.5       misho    11720: ** As well as the regular sqlite3changegroup_add() and
1.4       misho    11721: ** sqlite3changegroup_output() functions, also available are the streaming
                   11722: ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().
                   11723: */
1.5       misho    11724: SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp);
1.4       misho    11725: 
                   11726: /*
1.5       misho    11727: ** CAPI3REF: Add A Changeset To A Changegroup
                   11728: ** METHOD: sqlite3_changegroup
                   11729: **
1.4       misho    11730: ** Add all changes within the changeset (or patchset) in buffer pData (size
1.5       misho    11731: ** nData bytes) to the changegroup.
1.4       misho    11732: **
                   11733: ** If the buffer contains a patchset, then all prior calls to this function
                   11734: ** on the same changegroup object must also have specified patchsets. Or, if
                   11735: ** the buffer contains a changeset, so must have the earlier calls to this
                   11736: ** function. Otherwise, SQLITE_ERROR is returned and no changes are added
                   11737: ** to the changegroup.
                   11738: **
                   11739: ** Rows within the changeset and changegroup are identified by the values in
                   11740: ** their PRIMARY KEY columns. A change in the changeset is considered to
                   11741: ** apply to the same row as a change already present in the changegroup if
                   11742: ** the two rows have the same primary key.
                   11743: **
1.5       misho    11744: ** Changes to rows that do not already appear in the changegroup are
1.4       misho    11745: ** simply copied into it. Or, if both the new changeset and the changegroup
                   11746: ** contain changes that apply to a single row, the final contents of the
                   11747: ** changegroup depends on the type of each change, as follows:
                   11748: **
                   11749: ** <table border=1 style="margin-left:8ex;margin-right:8ex">
                   11750: **   <tr><th style="white-space:pre">Existing Change  </th>
                   11751: **       <th style="white-space:pre">New Change       </th>
                   11752: **       <th>Output Change
                   11753: **   <tr><td>INSERT <td>INSERT <td>
                   11754: **       The new change is ignored. This case does not occur if the new
                   11755: **       changeset was recorded immediately after the changesets already
                   11756: **       added to the changegroup.
                   11757: **   <tr><td>INSERT <td>UPDATE <td>
1.5       misho    11758: **       The INSERT change remains in the changegroup. The values in the
1.4       misho    11759: **       INSERT change are modified as if the row was inserted by the
                   11760: **       existing change and then updated according to the new change.
                   11761: **   <tr><td>INSERT <td>DELETE <td>
                   11762: **       The existing INSERT is removed from the changegroup. The DELETE is
                   11763: **       not added.
                   11764: **   <tr><td>UPDATE <td>INSERT <td>
                   11765: **       The new change is ignored. This case does not occur if the new
                   11766: **       changeset was recorded immediately after the changesets already
                   11767: **       added to the changegroup.
                   11768: **   <tr><td>UPDATE <td>UPDATE <td>
1.5       misho    11769: **       The existing UPDATE remains within the changegroup. It is amended
                   11770: **       so that the accompanying values are as if the row was updated once
1.4       misho    11771: **       by the existing change and then again by the new change.
                   11772: **   <tr><td>UPDATE <td>DELETE <td>
                   11773: **       The existing UPDATE is replaced by the new DELETE within the
                   11774: **       changegroup.
                   11775: **   <tr><td>DELETE <td>INSERT <td>
                   11776: **       If one or more of the column values in the row inserted by the
1.5       misho    11777: **       new change differ from those in the row deleted by the existing
1.4       misho    11778: **       change, the existing DELETE is replaced by an UPDATE within the
1.5       misho    11779: **       changegroup. Otherwise, if the inserted row is exactly the same
1.4       misho    11780: **       as the deleted row, the existing DELETE is simply discarded.
                   11781: **   <tr><td>DELETE <td>UPDATE <td>
                   11782: **       The new change is ignored. This case does not occur if the new
                   11783: **       changeset was recorded immediately after the changesets already
                   11784: **       added to the changegroup.
                   11785: **   <tr><td>DELETE <td>DELETE <td>
                   11786: **       The new change is ignored. This case does not occur if the new
                   11787: **       changeset was recorded immediately after the changesets already
                   11788: **       added to the changegroup.
                   11789: ** </table>
                   11790: **
                   11791: ** If the new changeset contains changes to a table that is already present
                   11792: ** in the changegroup, then the number of columns and the position of the
                   11793: ** primary key columns for the table must be consistent. If this is not the
                   11794: ** case, this function fails with SQLITE_SCHEMA. If the input changeset
                   11795: ** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is
                   11796: ** returned. Or, if an out-of-memory condition occurs during processing, this
1.5       misho    11797: ** function returns SQLITE_NOMEM. In all cases, if an error occurs the state
                   11798: ** of the final contents of the changegroup is undefined.
1.4       misho    11799: **
                   11800: ** If no error occurs, SQLITE_OK is returned.
                   11801: */
1.5       misho    11802: SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData);
1.4       misho    11803: 
                   11804: /*
1.5       misho    11805: ** CAPI3REF: Obtain A Composite Changeset From A Changegroup
                   11806: ** METHOD: sqlite3_changegroup
                   11807: **
1.4       misho    11808: ** Obtain a buffer containing a changeset (or patchset) representing the
                   11809: ** current contents of the changegroup. If the inputs to the changegroup
                   11810: ** were themselves changesets, the output is a changeset. Or, if the
                   11811: ** inputs were patchsets, the output is also a patchset.
                   11812: **
                   11813: ** As with the output of the sqlite3session_changeset() and
                   11814: ** sqlite3session_patchset() functions, all changes related to a single
                   11815: ** table are grouped together in the output of this function. Tables appear
                   11816: ** in the same order as for the very first changeset added to the changegroup.
                   11817: ** If the second or subsequent changesets added to the changegroup contain
                   11818: ** changes for tables that do not appear in the first changeset, they are
                   11819: ** appended onto the end of the output changeset, again in the order in
                   11820: ** which they are first encountered.
                   11821: **
                   11822: ** If an error occurs, an SQLite error code is returned and the output
                   11823: ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK
1.5       misho    11824: ** is returned and the output variables are set to the size of and a
1.4       misho    11825: ** pointer to the output buffer, respectively. In this case it is the
                   11826: ** responsibility of the caller to eventually free the buffer using a
                   11827: ** call to sqlite3_free().
                   11828: */
1.5       misho    11829: SQLITE_API int sqlite3changegroup_output(
1.4       misho    11830:   sqlite3_changegroup*,
                   11831:   int *pnData,                    /* OUT: Size of output buffer in bytes */
                   11832:   void **ppData                   /* OUT: Pointer to output buffer */
                   11833: );
                   11834: 
                   11835: /*
1.5       misho    11836: ** CAPI3REF: Delete A Changegroup Object
                   11837: ** DESTRUCTOR: sqlite3_changegroup
1.4       misho    11838: */
1.5       misho    11839: SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*);
1.4       misho    11840: 
                   11841: /*
                   11842: ** CAPI3REF: Apply A Changeset To A Database
                   11843: **
1.5       misho    11844: ** Apply a changeset or patchset to a database. These functions attempt to
                   11845: ** update the "main" database attached to handle db with the changes found in
                   11846: ** the changeset passed via the second and third arguments.
1.4       misho    11847: **
1.5       misho    11848: ** The fourth argument (xFilter) passed to these functions is the "filter
1.4       misho    11849: ** callback". If it is not NULL, then for each table affected by at least one
                   11850: ** change in the changeset, the filter callback is invoked with
                   11851: ** the table name as the second argument, and a copy of the context pointer
1.5       misho    11852: ** passed as the sixth argument as the first. If the "filter callback"
                   11853: ** returns zero, then no attempt is made to apply any changes to the table.
                   11854: ** Otherwise, if the return value is non-zero or the xFilter argument to
                   11855: ** is NULL, all changes related to the table are attempted.
1.4       misho    11856: **
1.5       misho    11857: ** For each table that is not excluded by the filter callback, this function
                   11858: ** tests that the target database contains a compatible table. A table is
1.4       misho    11859: ** considered compatible if all of the following are true:
                   11860: **
                   11861: ** <ul>
1.5       misho    11862: **   <li> The table has the same name as the name recorded in the
1.4       misho    11863: **        changeset, and
1.5       misho    11864: **   <li> The table has at least as many columns as recorded in the
1.4       misho    11865: **        changeset, and
1.5       misho    11866: **   <li> The table has primary key columns in the same position as
1.4       misho    11867: **        recorded in the changeset.
                   11868: ** </ul>
                   11869: **
                   11870: ** If there is no compatible table, it is not an error, but none of the
                   11871: ** changes associated with the table are applied. A warning message is issued
                   11872: ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most
                   11873: ** one such warning is issued for each table in the changeset.
                   11874: **
1.5       misho    11875: ** For each change for which there is a compatible table, an attempt is made
                   11876: ** to modify the table contents according to the UPDATE, INSERT or DELETE
                   11877: ** change. If a change cannot be applied cleanly, the conflict handler
                   11878: ** function passed as the fifth argument to sqlite3changeset_apply() may be
                   11879: ** invoked. A description of exactly when the conflict handler is invoked for
1.4       misho    11880: ** each type of change is below.
                   11881: **
                   11882: ** Unlike the xFilter argument, xConflict may not be passed NULL. The results
                   11883: ** of passing anything other than a valid function pointer as the xConflict
                   11884: ** argument are undefined.
                   11885: **
                   11886: ** Each time the conflict handler function is invoked, it must return one
1.5       misho    11887: ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or
1.4       misho    11888: ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned
                   11889: ** if the second argument passed to the conflict handler is either
                   11890: ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler
                   11891: ** returns an illegal value, any changes already made are rolled back and
1.5       misho    11892: ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different
1.4       misho    11893: ** actions are taken by sqlite3changeset_apply() depending on the value
                   11894: ** returned by each invocation of the conflict-handler function. Refer to
1.5       misho    11895: ** the documentation for the three
1.4       misho    11896: ** [SQLITE_CHANGESET_OMIT|available return values] for details.
                   11897: **
                   11898: ** <dl>
                   11899: ** <dt>DELETE Changes<dd>
1.5       misho    11900: **   For each DELETE change, the function checks if the target database
                   11901: **   contains a row with the same primary key value (or values) as the
                   11902: **   original row values stored in the changeset. If it does, and the values
                   11903: **   stored in all non-primary key columns also match the values stored in
1.4       misho    11904: **   the changeset the row is deleted from the target database.
                   11905: **
                   11906: **   If a row with matching primary key values is found, but one or more of
                   11907: **   the non-primary key fields contains a value different from the original
                   11908: **   row value stored in the changeset, the conflict-handler function is
1.5       misho    11909: **   invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the
                   11910: **   database table has more columns than are recorded in the changeset,
                   11911: **   only the values of those non-primary key fields are compared against
                   11912: **   the current database contents - any trailing database table columns
                   11913: **   are ignored.
1.4       misho    11914: **
                   11915: **   If no row with matching primary key values is found in the database,
                   11916: **   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
                   11917: **   passed as the second argument.
                   11918: **
                   11919: **   If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT
                   11920: **   (which can only happen if a foreign key constraint is violated), the
                   11921: **   conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]
                   11922: **   passed as the second argument. This includes the case where the DELETE
                   11923: **   operation is attempted because an earlier call to the conflict handler
                   11924: **   function returned [SQLITE_CHANGESET_REPLACE].
                   11925: **
                   11926: ** <dt>INSERT Changes<dd>
                   11927: **   For each INSERT change, an attempt is made to insert the new row into
1.5       misho    11928: **   the database. If the changeset row contains fewer fields than the
                   11929: **   database table, the trailing fields are populated with their default
                   11930: **   values.
1.4       misho    11931: **
1.5       misho    11932: **   If the attempt to insert the row fails because the database already
1.4       misho    11933: **   contains a row with the same primary key values, the conflict handler
1.5       misho    11934: **   function is invoked with the second argument set to
1.4       misho    11935: **   [SQLITE_CHANGESET_CONFLICT].
                   11936: **
                   11937: **   If the attempt to insert the row fails because of some other constraint
1.5       misho    11938: **   violation (e.g. NOT NULL or UNIQUE), the conflict handler function is
1.4       misho    11939: **   invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].
1.5       misho    11940: **   This includes the case where the INSERT operation is re-attempted because
                   11941: **   an earlier call to the conflict handler function returned
1.4       misho    11942: **   [SQLITE_CHANGESET_REPLACE].
                   11943: **
                   11944: ** <dt>UPDATE Changes<dd>
1.5       misho    11945: **   For each UPDATE change, the function checks if the target database
                   11946: **   contains a row with the same primary key value (or values) as the
                   11947: **   original row values stored in the changeset. If it does, and the values
                   11948: **   stored in all modified non-primary key columns also match the values
                   11949: **   stored in the changeset the row is updated within the target database.
1.4       misho    11950: **
                   11951: **   If a row with matching primary key values is found, but one or more of
1.5       misho    11952: **   the modified non-primary key fields contains a value different from an
                   11953: **   original row value stored in the changeset, the conflict-handler function
                   11954: **   is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since
1.4       misho    11955: **   UPDATE changes only contain values for non-primary key fields that are
                   11956: **   to be modified, only those fields need to match the original values to
                   11957: **   avoid the SQLITE_CHANGESET_DATA conflict-handler callback.
                   11958: **
                   11959: **   If no row with matching primary key values is found in the database,
                   11960: **   the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]
                   11961: **   passed as the second argument.
                   11962: **
1.5       misho    11963: **   If the UPDATE operation is attempted, but SQLite returns
                   11964: **   SQLITE_CONSTRAINT, the conflict-handler function is invoked with
1.4       misho    11965: **   [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.
1.5       misho    11966: **   This includes the case where the UPDATE operation is attempted after
1.4       misho    11967: **   an earlier call to the conflict handler function returned
1.5       misho    11968: **   [SQLITE_CHANGESET_REPLACE].
1.4       misho    11969: ** </dl>
                   11970: **
                   11971: ** It is safe to execute SQL statements, including those that write to the
                   11972: ** table that the callback related to, from within the xConflict callback.
1.5       misho    11973: ** This can be used to further customize the application's conflict
1.4       misho    11974: ** resolution strategy.
                   11975: **
1.5       misho    11976: ** All changes made by these functions are enclosed in a savepoint transaction.
1.4       misho    11977: ** If any other error (aside from a constraint failure when attempting to
                   11978: ** write to the target database) occurs, then the savepoint transaction is
1.5       misho    11979: ** rolled back, restoring the target database to its original state, and an
1.4       misho    11980: ** SQLite error code returned.
1.5       misho    11981: **
                   11982: ** If the output parameters (ppRebase) and (pnRebase) are non-NULL and
                   11983: ** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2()
                   11984: ** may set (*ppRebase) to point to a "rebase" that may be used with the
                   11985: ** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase)
                   11986: ** is set to the size of the buffer in bytes. It is the responsibility of the
                   11987: ** caller to eventually free any such buffer using sqlite3_free(). The buffer
                   11988: ** is only allocated and populated if one or more conflicts were encountered
                   11989: ** while applying the patchset. See comments surrounding the sqlite3_rebaser
                   11990: ** APIs for further details.
                   11991: **
                   11992: ** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent
                   11993: ** may be modified by passing a combination of
                   11994: ** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter.
                   11995: **
                   11996: ** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b>
                   11997: ** and therefore subject to change.
1.4       misho    11998: */
1.5       misho    11999: SQLITE_API int sqlite3changeset_apply(
1.4       misho    12000:   sqlite3 *db,                    /* Apply change to "main" db of this handle */
                   12001:   int nChangeset,                 /* Size of changeset in bytes */
                   12002:   void *pChangeset,               /* Changeset blob */
                   12003:   int(*xFilter)(
                   12004:     void *pCtx,                   /* Copy of sixth arg to _apply() */
                   12005:     const char *zTab              /* Table name */
                   12006:   ),
                   12007:   int(*xConflict)(
                   12008:     void *pCtx,                   /* Copy of sixth arg to _apply() */
                   12009:     int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
                   12010:     sqlite3_changeset_iter *p     /* Handle describing change and conflict */
                   12011:   ),
                   12012:   void *pCtx                      /* First argument passed to xConflict */
                   12013: );
1.5       misho    12014: SQLITE_API int sqlite3changeset_apply_v2(
                   12015:   sqlite3 *db,                    /* Apply change to "main" db of this handle */
                   12016:   int nChangeset,                 /* Size of changeset in bytes */
                   12017:   void *pChangeset,               /* Changeset blob */
                   12018:   int(*xFilter)(
                   12019:     void *pCtx,                   /* Copy of sixth arg to _apply() */
                   12020:     const char *zTab              /* Table name */
                   12021:   ),
                   12022:   int(*xConflict)(
                   12023:     void *pCtx,                   /* Copy of sixth arg to _apply() */
                   12024:     int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
                   12025:     sqlite3_changeset_iter *p     /* Handle describing change and conflict */
                   12026:   ),
                   12027:   void *pCtx,                     /* First argument passed to xConflict */
                   12028:   void **ppRebase, int *pnRebase, /* OUT: Rebase data */
                   12029:   int flags                       /* SESSION_CHANGESETAPPLY_* flags */
                   12030: );
1.4       misho    12031: 
1.5       misho    12032: /*
                   12033: ** CAPI3REF: Flags for sqlite3changeset_apply_v2
                   12034: **
                   12035: ** The following flags may passed via the 9th parameter to
                   12036: ** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]:
                   12037: **
                   12038: ** <dl>
                   12039: ** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd>
                   12040: **   Usually, the sessions module encloses all operations performed by
                   12041: **   a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The
                   12042: **   SAVEPOINT is committed if the changeset or patchset is successfully
                   12043: **   applied, or rolled back if an error occurs. Specifying this flag
                   12044: **   causes the sessions module to omit this savepoint. In this case, if the
                   12045: **   caller has an open transaction or savepoint when apply_v2() is called,
                   12046: **   it may revert the partially applied changeset by rolling it back.
                   12047: **
                   12048: ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd>
                   12049: **   Invert the changeset before applying it. This is equivalent to inverting
                   12050: **   a changeset using sqlite3changeset_invert() before applying it. It is
                   12051: **   an error to specify this flag with a patchset.
1.6.2.1 ! misho    12052: **
        !          12053: ** <dt>SQLITE_CHANGESETAPPLY_IGNORENOOP <dd>
        !          12054: **   Do not invoke the conflict handler callback for any changes that
        !          12055: **   would not actually modify the database even if they were applied.
        !          12056: **   Specifically, this means that the conflict handler is not invoked
        !          12057: **   for:
        !          12058: **    <ul>
        !          12059: **    <li>a delete change if the row being deleted cannot be found,
        !          12060: **    <li>an update change if the modified fields are already set to
        !          12061: **        their new values in the conflicting row, or
        !          12062: **    <li>an insert change if all fields of the conflicting row match
        !          12063: **        the row being inserted.
        !          12064: **    </ul>
1.5       misho    12065: */
                   12066: #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT   0x0001
                   12067: #define SQLITE_CHANGESETAPPLY_INVERT        0x0002
1.6.2.1 ! misho    12068: #define SQLITE_CHANGESETAPPLY_IGNORENOOP    0x0004
1.5       misho    12069: 
                   12070: /*
1.4       misho    12071: ** CAPI3REF: Constants Passed To The Conflict Handler
                   12072: **
                   12073: ** Values that may be passed as the second argument to a conflict-handler.
                   12074: **
                   12075: ** <dl>
                   12076: ** <dt>SQLITE_CHANGESET_DATA<dd>
                   12077: **   The conflict handler is invoked with CHANGESET_DATA as the second argument
                   12078: **   when processing a DELETE or UPDATE change if a row with the required
1.5       misho    12079: **   PRIMARY KEY fields is present in the database, but one or more other
                   12080: **   (non primary-key) fields modified by the update do not contain the
1.4       misho    12081: **   expected "before" values.
1.5       misho    12082: **
1.4       misho    12083: **   The conflicting row, in this case, is the database row with the matching
                   12084: **   primary key.
1.5       misho    12085: **
1.4       misho    12086: ** <dt>SQLITE_CHANGESET_NOTFOUND<dd>
                   12087: **   The conflict handler is invoked with CHANGESET_NOTFOUND as the second
                   12088: **   argument when processing a DELETE or UPDATE change if a row with the
                   12089: **   required PRIMARY KEY fields is not present in the database.
1.5       misho    12090: **
1.4       misho    12091: **   There is no conflicting row in this case. The results of invoking the
                   12092: **   sqlite3changeset_conflict() API are undefined.
1.5       misho    12093: **
1.4       misho    12094: ** <dt>SQLITE_CHANGESET_CONFLICT<dd>
                   12095: **   CHANGESET_CONFLICT is passed as the second argument to the conflict
1.5       misho    12096: **   handler while processing an INSERT change if the operation would result
1.4       misho    12097: **   in duplicate primary key values.
1.5       misho    12098: **
1.4       misho    12099: **   The conflicting row in this case is the database row with the matching
                   12100: **   primary key.
                   12101: **
                   12102: ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>
                   12103: **   If foreign key handling is enabled, and applying a changeset leaves the
1.5       misho    12104: **   database in a state containing foreign key violations, the conflict
1.4       misho    12105: **   handler is invoked with CHANGESET_FOREIGN_KEY as the second argument
                   12106: **   exactly once before the changeset is committed. If the conflict handler
                   12107: **   returns CHANGESET_OMIT, the changes, including those that caused the
                   12108: **   foreign key constraint violation, are committed. Or, if it returns
                   12109: **   CHANGESET_ABORT, the changeset is rolled back.
                   12110: **
                   12111: **   No current or conflicting row information is provided. The only function
                   12112: **   it is possible to call on the supplied sqlite3_changeset_iter handle
                   12113: **   is sqlite3changeset_fk_conflicts().
1.5       misho    12114: **
1.4       misho    12115: ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>
1.5       misho    12116: **   If any other constraint violation occurs while applying a change (i.e.
                   12117: **   a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is
1.4       misho    12118: **   invoked with CHANGESET_CONSTRAINT as the second argument.
1.5       misho    12119: **
1.4       misho    12120: **   There is no conflicting row in this case. The results of invoking the
                   12121: **   sqlite3changeset_conflict() API are undefined.
                   12122: **
                   12123: ** </dl>
                   12124: */
                   12125: #define SQLITE_CHANGESET_DATA        1
                   12126: #define SQLITE_CHANGESET_NOTFOUND    2
                   12127: #define SQLITE_CHANGESET_CONFLICT    3
                   12128: #define SQLITE_CHANGESET_CONSTRAINT  4
                   12129: #define SQLITE_CHANGESET_FOREIGN_KEY 5
                   12130: 
1.5       misho    12131: /*
1.4       misho    12132: ** CAPI3REF: Constants Returned By The Conflict Handler
                   12133: **
                   12134: ** A conflict handler callback must return one of the following three values.
                   12135: **
                   12136: ** <dl>
                   12137: ** <dt>SQLITE_CHANGESET_OMIT<dd>
                   12138: **   If a conflict handler returns this value no special action is taken. The
1.5       misho    12139: **   change that caused the conflict is not applied. The session module
1.4       misho    12140: **   continues to the next change in the changeset.
                   12141: **
                   12142: ** <dt>SQLITE_CHANGESET_REPLACE<dd>
                   12143: **   This value may only be returned if the second argument to the conflict
                   12144: **   handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this
1.5       misho    12145: **   is not the case, any changes applied so far are rolled back and the
1.4       misho    12146: **   call to sqlite3changeset_apply() returns SQLITE_MISUSE.
                   12147: **
                   12148: **   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict
                   12149: **   handler, then the conflicting row is either updated or deleted, depending
                   12150: **   on the type of change.
                   12151: **
                   12152: **   If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict
                   12153: **   handler, then the conflicting row is removed from the database and a
                   12154: **   second attempt to apply the change is made. If this second attempt fails,
                   12155: **   the original row is restored to the database before continuing.
                   12156: **
                   12157: ** <dt>SQLITE_CHANGESET_ABORT<dd>
1.5       misho    12158: **   If this value is returned, any changes applied so far are rolled back
1.4       misho    12159: **   and the call to sqlite3changeset_apply() returns SQLITE_ABORT.
                   12160: ** </dl>
                   12161: */
                   12162: #define SQLITE_CHANGESET_OMIT       0
                   12163: #define SQLITE_CHANGESET_REPLACE    1
                   12164: #define SQLITE_CHANGESET_ABORT      2
                   12165: 
                   12166: /*
1.5       misho    12167: ** CAPI3REF: Rebasing changesets
                   12168: ** EXPERIMENTAL
                   12169: **
                   12170: ** Suppose there is a site hosting a database in state S0. And that
                   12171: ** modifications are made that move that database to state S1 and a
                   12172: ** changeset recorded (the "local" changeset). Then, a changeset based
                   12173: ** on S0 is received from another site (the "remote" changeset) and
                   12174: ** applied to the database. The database is then in state
                   12175: ** (S1+"remote"), where the exact state depends on any conflict
                   12176: ** resolution decisions (OMIT or REPLACE) made while applying "remote".
                   12177: ** Rebasing a changeset is to update it to take those conflict
                   12178: ** resolution decisions into account, so that the same conflicts
                   12179: ** do not have to be resolved elsewhere in the network.
                   12180: **
                   12181: ** For example, if both the local and remote changesets contain an
                   12182: ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)":
                   12183: **
                   12184: **   local:  INSERT INTO t1 VALUES(1, 'v1');
                   12185: **   remote: INSERT INTO t1 VALUES(1, 'v2');
                   12186: **
                   12187: ** and the conflict resolution is REPLACE, then the INSERT change is
                   12188: ** removed from the local changeset (it was overridden). Or, if the
                   12189: ** conflict resolution was "OMIT", then the local changeset is modified
                   12190: ** to instead contain:
                   12191: **
                   12192: **           UPDATE t1 SET b = 'v2' WHERE a=1;
                   12193: **
                   12194: ** Changes within the local changeset are rebased as follows:
                   12195: **
                   12196: ** <dl>
                   12197: ** <dt>Local INSERT<dd>
                   12198: **   This may only conflict with a remote INSERT. If the conflict
                   12199: **   resolution was OMIT, then add an UPDATE change to the rebased
                   12200: **   changeset. Or, if the conflict resolution was REPLACE, add
                   12201: **   nothing to the rebased changeset.
                   12202: **
                   12203: ** <dt>Local DELETE<dd>
                   12204: **   This may conflict with a remote UPDATE or DELETE. In both cases the
                   12205: **   only possible resolution is OMIT. If the remote operation was a
                   12206: **   DELETE, then add no change to the rebased changeset. If the remote
                   12207: **   operation was an UPDATE, then the old.* fields of change are updated
                   12208: **   to reflect the new.* values in the UPDATE.
                   12209: **
                   12210: ** <dt>Local UPDATE<dd>
                   12211: **   This may conflict with a remote UPDATE or DELETE. If it conflicts
                   12212: **   with a DELETE, and the conflict resolution was OMIT, then the update
                   12213: **   is changed into an INSERT. Any undefined values in the new.* record
                   12214: **   from the update change are filled in using the old.* values from
                   12215: **   the conflicting DELETE. Or, if the conflict resolution was REPLACE,
                   12216: **   the UPDATE change is simply omitted from the rebased changeset.
                   12217: **
                   12218: **   If conflict is with a remote UPDATE and the resolution is OMIT, then
                   12219: **   the old.* values are rebased using the new.* values in the remote
                   12220: **   change. Or, if the resolution is REPLACE, then the change is copied
                   12221: **   into the rebased changeset with updates to columns also updated by
                   12222: **   the conflicting remote UPDATE removed. If this means no columns would
                   12223: **   be updated, the change is omitted.
                   12224: ** </dl>
                   12225: **
                   12226: ** A local change may be rebased against multiple remote changes
                   12227: ** simultaneously. If a single key is modified by multiple remote
                   12228: ** changesets, they are combined as follows before the local changeset
                   12229: ** is rebased:
                   12230: **
                   12231: ** <ul>
                   12232: **    <li> If there has been one or more REPLACE resolutions on a
                   12233: **         key, it is rebased according to a REPLACE.
                   12234: **
                   12235: **    <li> If there have been no REPLACE resolutions on a key, then
                   12236: **         the local changeset is rebased according to the most recent
                   12237: **         of the OMIT resolutions.
                   12238: ** </ul>
                   12239: **
                   12240: ** Note that conflict resolutions from multiple remote changesets are
                   12241: ** combined on a per-field basis, not per-row. This means that in the
                   12242: ** case of multiple remote UPDATE operations, some fields of a single
                   12243: ** local change may be rebased for REPLACE while others are rebased for
                   12244: ** OMIT.
                   12245: **
                   12246: ** In order to rebase a local changeset, the remote changeset must first
                   12247: ** be applied to the local database using sqlite3changeset_apply_v2() and
                   12248: ** the buffer of rebase information captured. Then:
                   12249: **
                   12250: ** <ol>
                   12251: **   <li> An sqlite3_rebaser object is created by calling
                   12252: **        sqlite3rebaser_create().
                   12253: **   <li> The new object is configured with the rebase buffer obtained from
                   12254: **        sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure().
                   12255: **        If the local changeset is to be rebased against multiple remote
                   12256: **        changesets, then sqlite3rebaser_configure() should be called
                   12257: **        multiple times, in the same order that the multiple
                   12258: **        sqlite3changeset_apply_v2() calls were made.
                   12259: **   <li> Each local changeset is rebased by calling sqlite3rebaser_rebase().
                   12260: **   <li> The sqlite3_rebaser object is deleted by calling
                   12261: **        sqlite3rebaser_delete().
                   12262: ** </ol>
                   12263: */
                   12264: typedef struct sqlite3_rebaser sqlite3_rebaser;
                   12265: 
                   12266: /*
                   12267: ** CAPI3REF: Create a changeset rebaser object.
                   12268: ** EXPERIMENTAL
                   12269: **
                   12270: ** Allocate a new changeset rebaser object. If successful, set (*ppNew) to
                   12271: ** point to the new object and return SQLITE_OK. Otherwise, if an error
                   12272: ** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew)
                   12273: ** to NULL.
                   12274: */
                   12275: SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew);
                   12276: 
                   12277: /*
                   12278: ** CAPI3REF: Configure a changeset rebaser object.
                   12279: ** EXPERIMENTAL
                   12280: **
                   12281: ** Configure the changeset rebaser object to rebase changesets according
                   12282: ** to the conflict resolutions described by buffer pRebase (size nRebase
                   12283: ** bytes), which must have been obtained from a previous call to
                   12284: ** sqlite3changeset_apply_v2().
                   12285: */
                   12286: SQLITE_API int sqlite3rebaser_configure(
                   12287:   sqlite3_rebaser*,
                   12288:   int nRebase, const void *pRebase
                   12289: );
                   12290: 
                   12291: /*
                   12292: ** CAPI3REF: Rebase a changeset
                   12293: ** EXPERIMENTAL
                   12294: **
                   12295: ** Argument pIn must point to a buffer containing a changeset nIn bytes
                   12296: ** in size. This function allocates and populates a buffer with a copy
                   12297: ** of the changeset rebased according to the configuration of the
                   12298: ** rebaser object passed as the first argument. If successful, (*ppOut)
                   12299: ** is set to point to the new buffer containing the rebased changeset and
                   12300: ** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the
                   12301: ** responsibility of the caller to eventually free the new buffer using
                   12302: ** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut)
                   12303: ** are set to zero and an SQLite error code returned.
                   12304: */
                   12305: SQLITE_API int sqlite3rebaser_rebase(
                   12306:   sqlite3_rebaser*,
                   12307:   int nIn, const void *pIn,
                   12308:   int *pnOut, void **ppOut
                   12309: );
                   12310: 
                   12311: /*
                   12312: ** CAPI3REF: Delete a changeset rebaser object.
                   12313: ** EXPERIMENTAL
                   12314: **
                   12315: ** Delete the changeset rebaser object and all associated resources. There
                   12316: ** should be one call to this function for each successful invocation
                   12317: ** of sqlite3rebaser_create().
                   12318: */
                   12319: SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p);
                   12320: 
                   12321: /*
1.4       misho    12322: ** CAPI3REF: Streaming Versions of API functions.
                   12323: **
1.5       misho    12324: ** The six streaming API xxx_strm() functions serve similar purposes to the
1.4       misho    12325: ** corresponding non-streaming API functions:
                   12326: **
                   12327: ** <table border=1 style="margin-left:8ex;margin-right:8ex">
                   12328: **   <tr><th>Streaming function<th>Non-streaming equivalent</th>
1.5       misho    12329: **   <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply]
                   12330: **   <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2]
                   12331: **   <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat]
                   12332: **   <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert]
                   12333: **   <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start]
                   12334: **   <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset]
                   12335: **   <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset]
1.4       misho    12336: ** </table>
                   12337: **
                   12338: ** Non-streaming functions that accept changesets (or patchsets) as input
1.5       misho    12339: ** require that the entire changeset be stored in a single buffer in memory.
                   12340: ** Similarly, those that return a changeset or patchset do so by returning
                   12341: ** a pointer to a single large buffer allocated using sqlite3_malloc().
                   12342: ** Normally this is convenient. However, if an application running in a
1.4       misho    12343: ** low-memory environment is required to handle very large changesets, the
                   12344: ** large contiguous memory allocations required can become onerous.
                   12345: **
                   12346: ** In order to avoid this problem, instead of a single large buffer, input
                   12347: ** is passed to a streaming API functions by way of a callback function that
                   12348: ** the sessions module invokes to incrementally request input data as it is
                   12349: ** required. In all cases, a pair of API function parameters such as
                   12350: **
                   12351: **  <pre>
                   12352: **  &nbsp;     int nChangeset,
                   12353: **  &nbsp;     void *pChangeset,
                   12354: **  </pre>
                   12355: **
                   12356: ** Is replaced by:
                   12357: **
                   12358: **  <pre>
                   12359: **  &nbsp;     int (*xInput)(void *pIn, void *pData, int *pnData),
                   12360: **  &nbsp;     void *pIn,
                   12361: **  </pre>
                   12362: **
                   12363: ** Each time the xInput callback is invoked by the sessions module, the first
1.5       misho    12364: ** argument passed is a copy of the supplied pIn context pointer. The second
                   12365: ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no
                   12366: ** error occurs the xInput method should copy up to (*pnData) bytes of data
                   12367: ** into the buffer and set (*pnData) to the actual number of bytes copied
                   12368: ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData)
                   12369: ** should be set to zero to indicate this. Or, if an error occurs, an SQLite
1.4       misho    12370: ** error code should be returned. In all cases, if an xInput callback returns
                   12371: ** an error, all processing is abandoned and the streaming API function
                   12372: ** returns a copy of the error code to the caller.
                   12373: **
                   12374: ** In the case of sqlite3changeset_start_strm(), the xInput callback may be
                   12375: ** invoked by the sessions module at any point during the lifetime of the
                   12376: ** iterator. If such an xInput callback returns an error, the iterator enters
1.5       misho    12377: ** an error state, whereby all subsequent calls to iterator functions
1.4       misho    12378: ** immediately fail with the same error code as returned by xInput.
                   12379: **
                   12380: ** Similarly, streaming API functions that return changesets (or patchsets)
                   12381: ** return them in chunks by way of a callback function instead of via a
                   12382: ** pointer to a single large buffer. In this case, a pair of parameters such
                   12383: ** as:
                   12384: **
                   12385: **  <pre>
                   12386: **  &nbsp;     int *pnChangeset,
                   12387: **  &nbsp;     void **ppChangeset,
                   12388: **  </pre>
                   12389: **
                   12390: ** Is replaced by:
                   12391: **
                   12392: **  <pre>
                   12393: **  &nbsp;     int (*xOutput)(void *pOut, const void *pData, int nData),
                   12394: **  &nbsp;     void *pOut
                   12395: **  </pre>
                   12396: **
                   12397: ** The xOutput callback is invoked zero or more times to return data to
                   12398: ** the application. The first parameter passed to each call is a copy of the
                   12399: ** pOut pointer supplied by the application. The second parameter, pData,
                   12400: ** points to a buffer nData bytes in size containing the chunk of output
                   12401: ** data being returned. If the xOutput callback successfully processes the
                   12402: ** supplied data, it should return SQLITE_OK to indicate success. Otherwise,
                   12403: ** it should return some other SQLite error code. In this case processing
                   12404: ** is immediately abandoned and the streaming API function returns a copy
                   12405: ** of the xOutput error code to the application.
                   12406: **
1.5       misho    12407: ** The sessions module never invokes an xOutput callback with the third
1.4       misho    12408: ** parameter set to a value less than or equal to zero. Other than this,
                   12409: ** no guarantees are made as to the size of the chunks of data returned.
                   12410: */
1.5       misho    12411: SQLITE_API int sqlite3changeset_apply_strm(
1.4       misho    12412:   sqlite3 *db,                    /* Apply change to "main" db of this handle */
                   12413:   int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
                   12414:   void *pIn,                                          /* First arg for xInput */
                   12415:   int(*xFilter)(
                   12416:     void *pCtx,                   /* Copy of sixth arg to _apply() */
                   12417:     const char *zTab              /* Table name */
                   12418:   ),
                   12419:   int(*xConflict)(
                   12420:     void *pCtx,                   /* Copy of sixth arg to _apply() */
                   12421:     int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
                   12422:     sqlite3_changeset_iter *p     /* Handle describing change and conflict */
                   12423:   ),
                   12424:   void *pCtx                      /* First argument passed to xConflict */
                   12425: );
1.5       misho    12426: SQLITE_API int sqlite3changeset_apply_v2_strm(
                   12427:   sqlite3 *db,                    /* Apply change to "main" db of this handle */
                   12428:   int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */
                   12429:   void *pIn,                                          /* First arg for xInput */
                   12430:   int(*xFilter)(
                   12431:     void *pCtx,                   /* Copy of sixth arg to _apply() */
                   12432:     const char *zTab              /* Table name */
                   12433:   ),
                   12434:   int(*xConflict)(
                   12435:     void *pCtx,                   /* Copy of sixth arg to _apply() */
                   12436:     int eConflict,                /* DATA, MISSING, CONFLICT, CONSTRAINT */
                   12437:     sqlite3_changeset_iter *p     /* Handle describing change and conflict */
                   12438:   ),
                   12439:   void *pCtx,                     /* First argument passed to xConflict */
                   12440:   void **ppRebase, int *pnRebase,
                   12441:   int flags
                   12442: );
                   12443: SQLITE_API int sqlite3changeset_concat_strm(
1.4       misho    12444:   int (*xInputA)(void *pIn, void *pData, int *pnData),
                   12445:   void *pInA,
                   12446:   int (*xInputB)(void *pIn, void *pData, int *pnData),
                   12447:   void *pInB,
                   12448:   int (*xOutput)(void *pOut, const void *pData, int nData),
                   12449:   void *pOut
                   12450: );
1.5       misho    12451: SQLITE_API int sqlite3changeset_invert_strm(
1.4       misho    12452:   int (*xInput)(void *pIn, void *pData, int *pnData),
                   12453:   void *pIn,
                   12454:   int (*xOutput)(void *pOut, const void *pData, int nData),
                   12455:   void *pOut
                   12456: );
1.5       misho    12457: SQLITE_API int sqlite3changeset_start_strm(
1.4       misho    12458:   sqlite3_changeset_iter **pp,
                   12459:   int (*xInput)(void *pIn, void *pData, int *pnData),
                   12460:   void *pIn
                   12461: );
1.5       misho    12462: SQLITE_API int sqlite3changeset_start_v2_strm(
                   12463:   sqlite3_changeset_iter **pp,
                   12464:   int (*xInput)(void *pIn, void *pData, int *pnData),
                   12465:   void *pIn,
                   12466:   int flags
                   12467: );
                   12468: SQLITE_API int sqlite3session_changeset_strm(
1.4       misho    12469:   sqlite3_session *pSession,
                   12470:   int (*xOutput)(void *pOut, const void *pData, int nData),
                   12471:   void *pOut
                   12472: );
1.5       misho    12473: SQLITE_API int sqlite3session_patchset_strm(
1.4       misho    12474:   sqlite3_session *pSession,
                   12475:   int (*xOutput)(void *pOut, const void *pData, int nData),
                   12476:   void *pOut
                   12477: );
1.5       misho    12478: SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*,
1.4       misho    12479:     int (*xInput)(void *pIn, void *pData, int *pnData),
                   12480:     void *pIn
                   12481: );
1.5       misho    12482: SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*,
                   12483:     int (*xOutput)(void *pOut, const void *pData, int nData),
1.4       misho    12484:     void *pOut
                   12485: );
1.5       misho    12486: SQLITE_API int sqlite3rebaser_rebase_strm(
                   12487:   sqlite3_rebaser *pRebaser,
                   12488:   int (*xInput)(void *pIn, void *pData, int *pnData),
                   12489:   void *pIn,
                   12490:   int (*xOutput)(void *pOut, const void *pData, int nData),
                   12491:   void *pOut
                   12492: );
                   12493: 
                   12494: /*
                   12495: ** CAPI3REF: Configure global parameters
                   12496: **
                   12497: ** The sqlite3session_config() interface is used to make global configuration
                   12498: ** changes to the sessions module in order to tune it to the specific needs
                   12499: ** of the application.
                   12500: **
                   12501: ** The sqlite3session_config() interface is not threadsafe. If it is invoked
                   12502: ** while any other thread is inside any other sessions method then the
                   12503: ** results are undefined. Furthermore, if it is invoked after any sessions
                   12504: ** related objects have been created, the results are also undefined.
                   12505: **
                   12506: ** The first argument to the sqlite3session_config() function must be one
                   12507: ** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The
                   12508: ** interpretation of the (void*) value passed as the second parameter and
                   12509: ** the effect of calling this function depends on the value of the first
                   12510: ** parameter.
                   12511: **
                   12512: ** <dl>
                   12513: ** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd>
                   12514: **    By default, the sessions module streaming interfaces attempt to input
                   12515: **    and output data in approximately 1 KiB chunks. This operand may be used
                   12516: **    to set and query the value of this configuration setting. The pointer
                   12517: **    passed as the second argument must point to a value of type (int).
                   12518: **    If this value is greater than 0, it is used as the new streaming data
                   12519: **    chunk size for both input and output. Before returning, the (int) value
                   12520: **    pointed to by pArg is set to the final value of the streaming interface
                   12521: **    chunk size.
                   12522: ** </dl>
                   12523: **
                   12524: ** This function returns SQLITE_OK if successful, or an SQLite error code
                   12525: ** otherwise.
                   12526: */
                   12527: SQLITE_API int sqlite3session_config(int op, void *pArg);
1.4       misho    12528: 
1.5       misho    12529: /*
                   12530: ** CAPI3REF: Values for sqlite3session_config().
                   12531: */
                   12532: #define SQLITE_SESSION_CONFIG_STRMSIZE 1
1.4       misho    12533: 
                   12534: /*
                   12535: ** Make sure we can call this stuff from C++.
                   12536: */
                   12537: #ifdef __cplusplus
                   12538: }
                   12539: #endif
                   12540: 
                   12541: #endif  /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */
                   12542: 
                   12543: /******** End of sqlite3session.h *********/
                   12544: /******** Begin file fts5.h *********/
                   12545: /*
                   12546: ** 2014 May 31
                   12547: **
                   12548: ** The author disclaims copyright to this source code.  In place of
                   12549: ** a legal notice, here is a blessing:
                   12550: **
                   12551: **    May you do good and not evil.
                   12552: **    May you find forgiveness for yourself and forgive others.
                   12553: **    May you share freely, never taking more than you give.
                   12554: **
                   12555: ******************************************************************************
                   12556: **
1.5       misho    12557: ** Interfaces to extend FTS5. Using the interfaces defined in this file,
1.4       misho    12558: ** FTS5 may be extended with:
                   12559: **
                   12560: **     * custom tokenizers, and
                   12561: **     * custom auxiliary functions.
                   12562: */
                   12563: 
                   12564: 
                   12565: #ifndef _FTS5_H
                   12566: #define _FTS5_H
                   12567: 
                   12568: 
                   12569: #ifdef __cplusplus
                   12570: extern "C" {
                   12571: #endif
                   12572: 
                   12573: /*************************************************************************
                   12574: ** CUSTOM AUXILIARY FUNCTIONS
                   12575: **
                   12576: ** Virtual table implementations may overload SQL functions by implementing
                   12577: ** the sqlite3_module.xFindFunction() method.
                   12578: */
                   12579: 
                   12580: typedef struct Fts5ExtensionApi Fts5ExtensionApi;
                   12581: typedef struct Fts5Context Fts5Context;
                   12582: typedef struct Fts5PhraseIter Fts5PhraseIter;
                   12583: 
                   12584: typedef void (*fts5_extension_function)(
                   12585:   const Fts5ExtensionApi *pApi,   /* API offered by current FTS version */
                   12586:   Fts5Context *pFts,              /* First arg to pass to pApi functions */
                   12587:   sqlite3_context *pCtx,          /* Context for returning result/error */
                   12588:   int nVal,                       /* Number of values in apVal[] array */
                   12589:   sqlite3_value **apVal           /* Array of trailing arguments */
                   12590: );
                   12591: 
                   12592: struct Fts5PhraseIter {
                   12593:   const unsigned char *a;
                   12594:   const unsigned char *b;
                   12595: };
                   12596: 
                   12597: /*
                   12598: ** EXTENSION API FUNCTIONS
                   12599: **
                   12600: ** xUserData(pFts):
1.5       misho    12601: **   Return a copy of the context pointer the extension function was
1.4       misho    12602: **   registered with.
                   12603: **
                   12604: ** xColumnTotalSize(pFts, iCol, pnToken):
                   12605: **   If parameter iCol is less than zero, set output variable *pnToken
                   12606: **   to the total number of tokens in the FTS5 table. Or, if iCol is
                   12607: **   non-negative but less than the number of columns in the table, return
1.5       misho    12608: **   the total number of tokens in column iCol, considering all rows in
1.4       misho    12609: **   the FTS5 table.
                   12610: **
                   12611: **   If parameter iCol is greater than or equal to the number of columns
                   12612: **   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
1.5       misho    12613: **   an OOM condition or IO error), an appropriate SQLite error code is
1.4       misho    12614: **   returned.
                   12615: **
                   12616: ** xColumnCount(pFts):
                   12617: **   Return the number of columns in the table.
                   12618: **
                   12619: ** xColumnSize(pFts, iCol, pnToken):
                   12620: **   If parameter iCol is less than zero, set output variable *pnToken
                   12621: **   to the total number of tokens in the current row. Or, if iCol is
                   12622: **   non-negative but less than the number of columns in the table, set
                   12623: **   *pnToken to the number of tokens in column iCol of the current row.
                   12624: **
                   12625: **   If parameter iCol is greater than or equal to the number of columns
                   12626: **   in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.
1.5       misho    12627: **   an OOM condition or IO error), an appropriate SQLite error code is
1.4       misho    12628: **   returned.
                   12629: **
                   12630: **   This function may be quite inefficient if used with an FTS5 table
                   12631: **   created with the "columnsize=0" option.
                   12632: **
                   12633: ** xColumnText:
                   12634: **   This function attempts to retrieve the text of column iCol of the
                   12635: **   current document. If successful, (*pz) is set to point to a buffer
                   12636: **   containing the text in utf-8 encoding, (*pn) is set to the size in bytes
                   12637: **   (not characters) of the buffer and SQLITE_OK is returned. Otherwise,
                   12638: **   if an error occurs, an SQLite error code is returned and the final values
                   12639: **   of (*pz) and (*pn) are undefined.
                   12640: **
                   12641: ** xPhraseCount:
                   12642: **   Returns the number of phrases in the current query expression.
                   12643: **
                   12644: ** xPhraseSize:
                   12645: **   Returns the number of tokens in phrase iPhrase of the query. Phrases
                   12646: **   are numbered starting from zero.
                   12647: **
                   12648: ** xInstCount:
                   12649: **   Set *pnInst to the total number of occurrences of all phrases within
                   12650: **   the query within the current row. Return SQLITE_OK if successful, or
                   12651: **   an error code (i.e. SQLITE_NOMEM) if an error occurs.
                   12652: **
                   12653: **   This API can be quite slow if used with an FTS5 table created with the
1.5       misho    12654: **   "detail=none" or "detail=column" option. If the FTS5 table is created
                   12655: **   with either "detail=none" or "detail=column" and "content=" option
1.4       misho    12656: **   (i.e. if it is a contentless table), then this API always returns 0.
                   12657: **
                   12658: ** xInst:
                   12659: **   Query for the details of phrase match iIdx within the current row.
                   12660: **   Phrase matches are numbered starting from zero, so the iIdx argument
                   12661: **   should be greater than or equal to zero and smaller than the value
                   12662: **   output by xInstCount().
                   12663: **
                   12664: **   Usually, output parameter *piPhrase is set to the phrase number, *piCol
                   12665: **   to the column in which it occurs and *piOff the token offset of the
1.5       misho    12666: **   first token of the phrase. Returns SQLITE_OK if successful, or an error
                   12667: **   code (i.e. SQLITE_NOMEM) if an error occurs.
1.4       misho    12668: **
                   12669: **   This API can be quite slow if used with an FTS5 table created with the
1.5       misho    12670: **   "detail=none" or "detail=column" option.
1.4       misho    12671: **
                   12672: ** xRowid:
                   12673: **   Returns the rowid of the current row.
                   12674: **
                   12675: ** xTokenize:
                   12676: **   Tokenize text using the tokenizer belonging to the FTS5 table.
                   12677: **
                   12678: ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):
                   12679: **   This API function is used to query the FTS table for phrase iPhrase
                   12680: **   of the current query. Specifically, a query equivalent to:
                   12681: **
                   12682: **       ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid
                   12683: **
                   12684: **   with $p set to a phrase equivalent to the phrase iPhrase of the
                   12685: **   current query is executed. Any column filter that applies to
1.5       misho    12686: **   phrase iPhrase of the current query is included in $p. For each
                   12687: **   row visited, the callback function passed as the fourth argument
                   12688: **   is invoked. The context and API objects passed to the callback
1.4       misho    12689: **   function may be used to access the properties of each matched row.
1.5       misho    12690: **   Invoking Api.xUserData() returns a copy of the pointer passed as
1.4       misho    12691: **   the third argument to pUserData.
                   12692: **
                   12693: **   If the callback function returns any value other than SQLITE_OK, the
                   12694: **   query is abandoned and the xQueryPhrase function returns immediately.
                   12695: **   If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.
                   12696: **   Otherwise, the error code is propagated upwards.
                   12697: **
                   12698: **   If the query runs to completion without incident, SQLITE_OK is returned.
                   12699: **   Or, if some error occurs before the query completes or is aborted by
                   12700: **   the callback, an SQLite error code is returned.
                   12701: **
                   12702: **
                   12703: ** xSetAuxdata(pFts5, pAux, xDelete)
                   12704: **
1.5       misho    12705: **   Save the pointer passed as the second argument as the extension function's
1.4       misho    12706: **   "auxiliary data". The pointer may then be retrieved by the current or any
                   12707: **   future invocation of the same fts5 extension function made as part of
1.5       misho    12708: **   the same MATCH query using the xGetAuxdata() API.
1.4       misho    12709: **
                   12710: **   Each extension function is allocated a single auxiliary data slot for
1.5       misho    12711: **   each FTS query (MATCH expression). If the extension function is invoked
                   12712: **   more than once for a single FTS query, then all invocations share a
1.4       misho    12713: **   single auxiliary data context.
                   12714: **
                   12715: **   If there is already an auxiliary data pointer when this function is
                   12716: **   invoked, then it is replaced by the new pointer. If an xDelete callback
                   12717: **   was specified along with the original pointer, it is invoked at this
                   12718: **   point.
                   12719: **
                   12720: **   The xDelete callback, if one is specified, is also invoked on the
                   12721: **   auxiliary data pointer after the FTS5 query has finished.
                   12722: **
1.5       misho    12723: **   If an error (e.g. an OOM condition) occurs within this function,
1.4       misho    12724: **   the auxiliary data is set to NULL and an error code returned. If the
                   12725: **   xDelete parameter was not NULL, it is invoked on the auxiliary data
                   12726: **   pointer before returning.
                   12727: **
                   12728: **
                   12729: ** xGetAuxdata(pFts5, bClear)
                   12730: **
1.5       misho    12731: **   Returns the current auxiliary data pointer for the fts5 extension
1.4       misho    12732: **   function. See the xSetAuxdata() method for details.
                   12733: **
                   12734: **   If the bClear argument is non-zero, then the auxiliary data is cleared
                   12735: **   (set to NULL) before this function returns. In this case the xDelete,
                   12736: **   if any, is not invoked.
                   12737: **
                   12738: **
                   12739: ** xRowCount(pFts5, pnRow)
                   12740: **
                   12741: **   This function is used to retrieve the total number of rows in the table.
                   12742: **   In other words, the same value that would be returned by:
                   12743: **
                   12744: **        SELECT count(*) FROM ftstable;
                   12745: **
                   12746: ** xPhraseFirst()
                   12747: **   This function is used, along with type Fts5PhraseIter and the xPhraseNext
                   12748: **   method, to iterate through all instances of a single query phrase within
                   12749: **   the current row. This is the same information as is accessible via the
                   12750: **   xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient
1.5       misho    12751: **   to use, this API may be faster under some circumstances. To iterate
1.4       misho    12752: **   through instances of phrase iPhrase, use the following code:
                   12753: **
                   12754: **       Fts5PhraseIter iter;
                   12755: **       int iCol, iOff;
                   12756: **       for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);
                   12757: **           iCol>=0;
                   12758: **           pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)
                   12759: **       ){
                   12760: **         // An instance of phrase iPhrase at offset iOff of column iCol
                   12761: **       }
                   12762: **
                   12763: **   The Fts5PhraseIter structure is defined above. Applications should not
                   12764: **   modify this structure directly - it should only be used as shown above
                   12765: **   with the xPhraseFirst() and xPhraseNext() API methods (and by
                   12766: **   xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).
                   12767: **
                   12768: **   This API can be quite slow if used with an FTS5 table created with the
1.5       misho    12769: **   "detail=none" or "detail=column" option. If the FTS5 table is created
                   12770: **   with either "detail=none" or "detail=column" and "content=" option
1.4       misho    12771: **   (i.e. if it is a contentless table), then this API always iterates
                   12772: **   through an empty set (all calls to xPhraseFirst() set iCol to -1).
                   12773: **
                   12774: ** xPhraseNext()
                   12775: **   See xPhraseFirst above.
                   12776: **
                   12777: ** xPhraseFirstColumn()
                   12778: **   This function and xPhraseNextColumn() are similar to the xPhraseFirst()
                   12779: **   and xPhraseNext() APIs described above. The difference is that instead
                   12780: **   of iterating through all instances of a phrase in the current row, these
                   12781: **   APIs are used to iterate through the set of columns in the current row
                   12782: **   that contain one or more instances of a specified phrase. For example:
                   12783: **
                   12784: **       Fts5PhraseIter iter;
                   12785: **       int iCol;
                   12786: **       for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);
                   12787: **           iCol>=0;
                   12788: **           pApi->xPhraseNextColumn(pFts, &iter, &iCol)
                   12789: **       ){
                   12790: **         // Column iCol contains at least one instance of phrase iPhrase
                   12791: **       }
                   12792: **
                   12793: **   This API can be quite slow if used with an FTS5 table created with the
1.5       misho    12794: **   "detail=none" option. If the FTS5 table is created with either
                   12795: **   "detail=none" "content=" option (i.e. if it is a contentless table),
                   12796: **   then this API always iterates through an empty set (all calls to
1.4       misho    12797: **   xPhraseFirstColumn() set iCol to -1).
                   12798: **
                   12799: **   The information accessed using this API and its companion
                   12800: **   xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext
                   12801: **   (or xInst/xInstCount). The chief advantage of this API is that it is
                   12802: **   significantly more efficient than those alternatives when used with
1.5       misho    12803: **   "detail=column" tables.
1.4       misho    12804: **
                   12805: ** xPhraseNextColumn()
                   12806: **   See xPhraseFirstColumn above.
                   12807: */
                   12808: struct Fts5ExtensionApi {
1.6.2.1 ! misho    12809:   int iVersion;                   /* Currently always set to 2 */
1.4       misho    12810: 
                   12811:   void *(*xUserData)(Fts5Context*);
                   12812: 
                   12813:   int (*xColumnCount)(Fts5Context*);
                   12814:   int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow);
                   12815:   int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken);
                   12816: 
1.5       misho    12817:   int (*xTokenize)(Fts5Context*,
1.4       misho    12818:     const char *pText, int nText, /* Text to tokenize */
                   12819:     void *pCtx,                   /* Context passed to xToken() */
                   12820:     int (*xToken)(void*, int, const char*, int, int, int)       /* Callback */
                   12821:   );
                   12822: 
                   12823:   int (*xPhraseCount)(Fts5Context*);
                   12824:   int (*xPhraseSize)(Fts5Context*, int iPhrase);
                   12825: 
                   12826:   int (*xInstCount)(Fts5Context*, int *pnInst);
                   12827:   int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff);
                   12828: 
                   12829:   sqlite3_int64 (*xRowid)(Fts5Context*);
                   12830:   int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn);
                   12831:   int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken);
                   12832: 
                   12833:   int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData,
                   12834:     int(*)(const Fts5ExtensionApi*,Fts5Context*,void*)
                   12835:   );
                   12836:   int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*));
                   12837:   void *(*xGetAuxdata)(Fts5Context*, int bClear);
                   12838: 
                   12839:   int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*);
                   12840:   void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff);
                   12841: 
                   12842:   int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*);
                   12843:   void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol);
                   12844: };
                   12845: 
1.5       misho    12846: /*
1.4       misho    12847: ** CUSTOM AUXILIARY FUNCTIONS
                   12848: *************************************************************************/
                   12849: 
                   12850: /*************************************************************************
                   12851: ** CUSTOM TOKENIZERS
                   12852: **
1.5       misho    12853: ** Applications may also register custom tokenizer types. A tokenizer
                   12854: ** is registered by providing fts5 with a populated instance of the
1.4       misho    12855: ** following structure. All structure methods must be defined, setting
                   12856: ** any member of the fts5_tokenizer struct to NULL leads to undefined
                   12857: ** behaviour. The structure methods are expected to function as follows:
                   12858: **
                   12859: ** xCreate:
                   12860: **   This function is used to allocate and initialize a tokenizer instance.
                   12861: **   A tokenizer instance is required to actually tokenize text.
                   12862: **
                   12863: **   The first argument passed to this function is a copy of the (void*)
                   12864: **   pointer provided by the application when the fts5_tokenizer object
1.5       misho    12865: **   was registered with FTS5 (the third argument to xCreateTokenizer()).
1.4       misho    12866: **   The second and third arguments are an array of nul-terminated strings
                   12867: **   containing the tokenizer arguments, if any, specified following the
                   12868: **   tokenizer name as part of the CREATE VIRTUAL TABLE statement used
                   12869: **   to create the FTS5 table.
                   12870: **
1.5       misho    12871: **   The final argument is an output variable. If successful, (*ppOut)
1.4       misho    12872: **   should be set to point to the new tokenizer handle and SQLITE_OK
                   12873: **   returned. If an error occurs, some value other than SQLITE_OK should
1.5       misho    12874: **   be returned. In this case, fts5 assumes that the final value of *ppOut
1.4       misho    12875: **   is undefined.
                   12876: **
                   12877: ** xDelete:
                   12878: **   This function is invoked to delete a tokenizer handle previously
                   12879: **   allocated using xCreate(). Fts5 guarantees that this function will
                   12880: **   be invoked exactly once for each successful call to xCreate().
                   12881: **
                   12882: ** xTokenize:
1.5       misho    12883: **   This function is expected to tokenize the nText byte string indicated
1.4       misho    12884: **   by argument pText. pText may or may not be nul-terminated. The first
                   12885: **   argument passed to this function is a pointer to an Fts5Tokenizer object
                   12886: **   returned by an earlier call to xCreate().
                   12887: **
                   12888: **   The second argument indicates the reason that FTS5 is requesting
                   12889: **   tokenization of the supplied text. This is always one of the following
                   12890: **   four values:
                   12891: **
                   12892: **   <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into
                   12893: **            or removed from the FTS table. The tokenizer is being invoked to
                   12894: **            determine the set of tokens to add to (or delete from) the
                   12895: **            FTS index.
                   12896: **
1.5       misho    12897: **       <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed
                   12898: **            against the FTS index. The tokenizer is being called to tokenize
1.4       misho    12899: **            a bareword or quoted string specified as part of the query.
                   12900: **
                   12901: **       <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as
                   12902: **            FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is
                   12903: **            followed by a "*" character, indicating that the last token
                   12904: **            returned by the tokenizer will be treated as a token prefix.
                   12905: **
1.5       misho    12906: **       <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to
1.4       misho    12907: **            satisfy an fts5_api.xTokenize() request made by an auxiliary
                   12908: **            function. Or an fts5_api.xColumnSize() request made by the same
1.5       misho    12909: **            on a columnsize=0 database.
1.4       misho    12910: **   </ul>
                   12911: **
                   12912: **   For each token in the input string, the supplied callback xToken() must
                   12913: **   be invoked. The first argument to it should be a copy of the pointer
                   12914: **   passed as the second argument to xTokenize(). The third and fourth
                   12915: **   arguments are a pointer to a buffer containing the token text, and the
                   12916: **   size of the token in bytes. The 4th and 5th arguments are the byte offsets
                   12917: **   of the first byte of and first byte immediately following the text from
                   12918: **   which the token is derived within the input.
                   12919: **
                   12920: **   The second argument passed to the xToken() callback ("tflags") should
1.5       misho    12921: **   normally be set to 0. The exception is if the tokenizer supports
1.4       misho    12922: **   synonyms. In this case see the discussion below for details.
                   12923: **
1.5       misho    12924: **   FTS5 assumes the xToken() callback is invoked for each token in the
1.4       misho    12925: **   order that they occur within the input text.
                   12926: **
                   12927: **   If an xToken() callback returns any value other than SQLITE_OK, then
                   12928: **   the tokenization should be abandoned and the xTokenize() method should
                   12929: **   immediately return a copy of the xToken() return value. Or, if the
                   12930: **   input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,
                   12931: **   if an error occurs with the xTokenize() implementation itself, it
                   12932: **   may abandon the tokenization and return any error code other than
                   12933: **   SQLITE_OK or SQLITE_DONE.
                   12934: **
                   12935: ** SYNONYM SUPPORT
                   12936: **
                   12937: **   Custom tokenizers may also support synonyms. Consider a case in which a
1.5       misho    12938: **   user wishes to query for a phrase such as "first place". Using the
1.4       misho    12939: **   built-in tokenizers, the FTS5 query 'first + place' will match instances
                   12940: **   of "first place" within the document set, but not alternative forms
                   12941: **   such as "1st place". In some applications, it would be better to match
                   12942: **   all instances of "first place" or "1st place" regardless of which form
                   12943: **   the user specified in the MATCH query text.
                   12944: **
                   12945: **   There are several ways to approach this in FTS5:
                   12946: **
1.5       misho    12947: **   <ol><li> By mapping all synonyms to a single token. In this case, using
                   12948: **            the above example, this means that the tokenizer returns the
1.4       misho    12949: **            same token for inputs "first" and "1st". Say that token is in
                   12950: **            fact "first", so that when the user inserts the document "I won
                   12951: **            1st place" entries are added to the index for tokens "i", "won",
                   12952: **            "first" and "place". If the user then queries for '1st + place',
                   12953: **            the tokenizer substitutes "first" for "1st" and the query works
                   12954: **            as expected.
                   12955: **
1.5       misho    12956: **       <li> By querying the index for all synonyms of each query term
                   12957: **            separately. In this case, when tokenizing query text, the
                   12958: **            tokenizer may provide multiple synonyms for a single term
                   12959: **            within the document. FTS5 then queries the index for each
                   12960: **            synonym individually. For example, faced with the query:
1.4       misho    12961: **
                   12962: **   <codeblock>
                   12963: **     ... MATCH 'first place'</codeblock>
                   12964: **
                   12965: **            the tokenizer offers both "1st" and "first" as synonyms for the
1.5       misho    12966: **            first token in the MATCH query and FTS5 effectively runs a query
1.4       misho    12967: **            similar to:
                   12968: **
                   12969: **   <codeblock>
                   12970: **     ... MATCH '(first OR 1st) place'</codeblock>
                   12971: **
                   12972: **            except that, for the purposes of auxiliary functions, the query
1.5       misho    12973: **            still appears to contain just two phrases - "(first OR 1st)"
1.4       misho    12974: **            being treated as a single phrase.
                   12975: **
                   12976: **       <li> By adding multiple synonyms for a single term to the FTS index.
                   12977: **            Using this method, when tokenizing document text, the tokenizer
1.5       misho    12978: **            provides multiple synonyms for each token. So that when a
1.4       misho    12979: **            document such as "I won first place" is tokenized, entries are
                   12980: **            added to the FTS index for "i", "won", "first", "1st" and
                   12981: **            "place".
                   12982: **
                   12983: **            This way, even if the tokenizer does not provide synonyms
1.5       misho    12984: **            when tokenizing query text (it should not - to do so would be
                   12985: **            inefficient), it doesn't matter if the user queries for
                   12986: **            'first + place' or '1st + place', as there are entries in the
1.4       misho    12987: **            FTS index corresponding to both forms of the first token.
                   12988: **   </ol>
                   12989: **
                   12990: **   Whether it is parsing document or query text, any call to xToken that
                   12991: **   specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit
                   12992: **   is considered to supply a synonym for the previous token. For example,
                   12993: **   when parsing the document "I won first place", a tokenizer that supports
                   12994: **   synonyms would call xToken() 5 times, as follows:
                   12995: **
                   12996: **   <codeblock>
                   12997: **       xToken(pCtx, 0, "i",                      1,  0,  1);
                   12998: **       xToken(pCtx, 0, "won",                    3,  2,  5);
                   12999: **       xToken(pCtx, 0, "first",                  5,  6, 11);
                   13000: **       xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3,  6, 11);
                   13001: **       xToken(pCtx, 0, "place",                  5, 12, 17);
                   13002: **</codeblock>
                   13003: **
                   13004: **   It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time
                   13005: **   xToken() is called. Multiple synonyms may be specified for a single token
1.5       misho    13006: **   by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence.
1.4       misho    13007: **   There is no limit to the number of synonyms that may be provided for a
                   13008: **   single token.
                   13009: **
1.5       misho    13010: **   In many cases, method (1) above is the best approach. It does not add
1.4       misho    13011: **   extra data to the FTS index or require FTS5 to query for multiple terms,
                   13012: **   so it is efficient in terms of disk space and query speed. However, it
                   13013: **   does not support prefix queries very well. If, as suggested above, the
1.5       misho    13014: **   token "first" is substituted for "1st" by the tokenizer, then the query:
1.4       misho    13015: **
                   13016: **   <codeblock>
                   13017: **     ... MATCH '1s*'</codeblock>
                   13018: **
                   13019: **   will not match documents that contain the token "1st" (as the tokenizer
                   13020: **   will probably not map "1s" to any prefix of "first").
                   13021: **
1.5       misho    13022: **   For full prefix support, method (3) may be preferred. In this case,
1.4       misho    13023: **   because the index contains entries for both "first" and "1st", prefix
                   13024: **   queries such as 'fi*' or '1s*' will match correctly. However, because
                   13025: **   extra entries are added to the FTS index, this method uses more space
                   13026: **   within the database.
                   13027: **
                   13028: **   Method (2) offers a midpoint between (1) and (3). Using this method,
1.5       misho    13029: **   a query such as '1s*' will match documents that contain the literal
1.4       misho    13030: **   token "1st", but not "first" (assuming the tokenizer is not able to
                   13031: **   provide synonyms for prefixes). However, a non-prefix query like '1st'
                   13032: **   will match against "1st" and "first". This method does not require
1.5       misho    13033: **   extra disk space, as no extra entries are added to the FTS index.
1.4       misho    13034: **   On the other hand, it may require more CPU cycles to run MATCH queries,
                   13035: **   as separate queries of the FTS index are required for each synonym.
                   13036: **
                   13037: **   When using methods (2) or (3), it is important that the tokenizer only
1.6.2.1 ! misho    13038: **   provide synonyms when tokenizing document text (method (3)) or query
        !          13039: **   text (method (2)), not both. Doing so will not cause any errors, but is
1.4       misho    13040: **   inefficient.
                   13041: */
                   13042: typedef struct Fts5Tokenizer Fts5Tokenizer;
                   13043: typedef struct fts5_tokenizer fts5_tokenizer;
                   13044: struct fts5_tokenizer {
                   13045:   int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut);
                   13046:   void (*xDelete)(Fts5Tokenizer*);
1.5       misho    13047:   int (*xTokenize)(Fts5Tokenizer*,
1.4       misho    13048:       void *pCtx,
                   13049:       int flags,            /* Mask of FTS5_TOKENIZE_* flags */
1.5       misho    13050:       const char *pText, int nText,
1.4       misho    13051:       int (*xToken)(
                   13052:         void *pCtx,         /* Copy of 2nd argument to xTokenize() */
                   13053:         int tflags,         /* Mask of FTS5_TOKEN_* flags */
                   13054:         const char *pToken, /* Pointer to buffer containing token */
                   13055:         int nToken,         /* Size of token in bytes */
                   13056:         int iStart,         /* Byte offset of token within input text */
                   13057:         int iEnd            /* Byte offset of end of token within input text */
                   13058:       )
                   13059:   );
                   13060: };
                   13061: 
                   13062: /* Flags that may be passed as the third argument to xTokenize() */
                   13063: #define FTS5_TOKENIZE_QUERY     0x0001
                   13064: #define FTS5_TOKENIZE_PREFIX    0x0002
                   13065: #define FTS5_TOKENIZE_DOCUMENT  0x0004
                   13066: #define FTS5_TOKENIZE_AUX       0x0008
                   13067: 
                   13068: /* Flags that may be passed by the tokenizer implementation back to FTS5
                   13069: ** as the third argument to the supplied xToken callback. */
                   13070: #define FTS5_TOKEN_COLOCATED    0x0001      /* Same position as prev. token */
                   13071: 
                   13072: /*
                   13073: ** END OF CUSTOM TOKENIZERS
                   13074: *************************************************************************/
                   13075: 
                   13076: /*************************************************************************
                   13077: ** FTS5 EXTENSION REGISTRATION API
                   13078: */
                   13079: typedef struct fts5_api fts5_api;
                   13080: struct fts5_api {
                   13081:   int iVersion;                   /* Currently always set to 2 */
                   13082: 
                   13083:   /* Create a new tokenizer */
                   13084:   int (*xCreateTokenizer)(
                   13085:     fts5_api *pApi,
                   13086:     const char *zName,
1.6.2.1 ! misho    13087:     void *pUserData,
1.4       misho    13088:     fts5_tokenizer *pTokenizer,
                   13089:     void (*xDestroy)(void*)
                   13090:   );
                   13091: 
                   13092:   /* Find an existing tokenizer */
                   13093:   int (*xFindTokenizer)(
                   13094:     fts5_api *pApi,
                   13095:     const char *zName,
1.6.2.1 ! misho    13096:     void **ppUserData,
1.4       misho    13097:     fts5_tokenizer *pTokenizer
                   13098:   );
                   13099: 
                   13100:   /* Create a new auxiliary function */
                   13101:   int (*xCreateFunction)(
                   13102:     fts5_api *pApi,
                   13103:     const char *zName,
1.6.2.1 ! misho    13104:     void *pUserData,
1.4       misho    13105:     fts5_extension_function xFunction,
                   13106:     void (*xDestroy)(void*)
                   13107:   );
                   13108: };
                   13109: 
                   13110: /*
                   13111: ** END OF REGISTRATION API
                   13112: *************************************************************************/
                   13113: 
                   13114: #ifdef __cplusplus
                   13115: }  /* end of the 'extern "C"' block */
                   13116: #endif
                   13117: 
                   13118: #endif /* _FTS5_H */
                   13119: 
                   13120: /******** End of fts5.h *********/

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