Annotation of embedaddon/sqlite3/src/sqlite.h.in, revision 1.1
1.1 ! misho 1: /*
! 2: ** 2001 September 15
! 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
! 26: ** on how SQLite interfaces are suppose to operate.
! 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: */
! 33: #ifndef _SQLITE3_H_
! 34: #define _SQLITE3_H_
! 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: /*
! 46: ** Add the ability to override 'extern'
! 47: */
! 48: #ifndef SQLITE_EXTERN
! 49: # define SQLITE_EXTERN extern
! 50: #endif
! 51:
! 52: /*
! 53: ** These no-op macros are used in front of interfaces to mark those
! 54: ** interfaces as either deprecated or experimental. New applications
! 55: ** should not use deprecated interfaces - they are support for backwards
! 56: ** compatibility only. Application writers should be aware that
! 57: ** experimental interfaces are subject to change in point releases.
! 58: **
! 59: ** These macros used to resolve to various kinds of compiler magic that
! 60: ** would generate warning messages when they were used. But that
! 61: ** compiler magic ended up generating such a flurry of bug reports
! 62: ** that we have taken it all out and gone back to using simple
! 63: ** noop macros.
! 64: */
! 65: #define SQLITE_DEPRECATED
! 66: #define SQLITE_EXPERIMENTAL
! 67:
! 68: /*
! 69: ** Ensure these symbols were not defined by some previous header file.
! 70: */
! 71: #ifdef SQLITE_VERSION
! 72: # undef SQLITE_VERSION
! 73: #endif
! 74: #ifdef SQLITE_VERSION_NUMBER
! 75: # undef SQLITE_VERSION_NUMBER
! 76: #endif
! 77:
! 78: /*
! 79: ** CAPI3REF: Compile-Time Library Version Numbers
! 80: **
! 81: ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
! 82: ** evaluates to a string literal that is the SQLite version in the
! 83: ** format "X.Y.Z" where X is the major version number (always 3 for
! 84: ** SQLite3) and Y is the minor version number and Z is the release number.)^
! 85: ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
! 86: ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
! 87: ** numbers used in [SQLITE_VERSION].)^
! 88: ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
! 89: ** be larger than the release from which it is derived. Either Y will
! 90: ** be held constant and Z will be incremented or else Y will be incremented
! 91: ** and Z will be reset to zero.
! 92: **
! 93: ** Since version 3.6.18, SQLite source code has been stored in the
! 94: ** <a href="http://www.fossil-scm.org/">Fossil configuration management
! 95: ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
! 96: ** a string which identifies a particular check-in of SQLite
! 97: ** within its configuration management system. ^The SQLITE_SOURCE_ID
! 98: ** string contains the date and time of the check-in (UTC) and an SHA1
! 99: ** hash of the entire source tree.
! 100: **
! 101: ** See also: [sqlite3_libversion()],
! 102: ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
! 103: ** [sqlite_version()] and [sqlite_source_id()].
! 104: */
! 105: #define SQLITE_VERSION "--VERS--"
! 106: #define SQLITE_VERSION_NUMBER --VERSION-NUMBER--
! 107: #define SQLITE_SOURCE_ID "--SOURCE-ID--"
! 108:
! 109: /*
! 110: ** CAPI3REF: Run-Time Library Version Numbers
! 111: ** KEYWORDS: sqlite3_version, sqlite3_sourceid
! 112: **
! 113: ** These interfaces provide the same information as the [SQLITE_VERSION],
! 114: ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
! 115: ** but are associated with the library instead of the header file. ^(Cautious
! 116: ** programmers might include assert() statements in their application to
! 117: ** verify that values returned by these interfaces match the macros in
! 118: ** the header, and thus insure that the application is
! 119: ** compiled with matching library and header files.
! 120: **
! 121: ** <blockquote><pre>
! 122: ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
! 123: ** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
! 124: ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
! 125: ** </pre></blockquote>)^
! 126: **
! 127: ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
! 128: ** macro. ^The sqlite3_libversion() function returns a pointer to the
! 129: ** to the sqlite3_version[] string constant. The sqlite3_libversion()
! 130: ** function is provided for use in DLLs since DLL users usually do not have
! 131: ** direct access to string constants within the DLL. ^The
! 132: ** sqlite3_libversion_number() function returns an integer equal to
! 133: ** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
! 134: ** a pointer to a string constant whose value is the same as the
! 135: ** [SQLITE_SOURCE_ID] C preprocessor macro.
! 136: **
! 137: ** See also: [sqlite_version()] and [sqlite_source_id()].
! 138: */
! 139: SQLITE_EXTERN const char sqlite3_version[];
! 140: const char *sqlite3_libversion(void);
! 141: const char *sqlite3_sourceid(void);
! 142: int sqlite3_libversion_number(void);
! 143:
! 144: /*
! 145: ** CAPI3REF: Run-Time Library Compilation Options Diagnostics
! 146: **
! 147: ** ^The sqlite3_compileoption_used() function returns 0 or 1
! 148: ** indicating whether the specified option was defined at
! 149: ** compile time. ^The SQLITE_ prefix may be omitted from the
! 150: ** option name passed to sqlite3_compileoption_used().
! 151: **
! 152: ** ^The sqlite3_compileoption_get() function allows iterating
! 153: ** over the list of options that were defined at compile time by
! 154: ** returning the N-th compile time option string. ^If N is out of range,
! 155: ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
! 156: ** prefix is omitted from any strings returned by
! 157: ** sqlite3_compileoption_get().
! 158: **
! 159: ** ^Support for the diagnostic functions sqlite3_compileoption_used()
! 160: ** and sqlite3_compileoption_get() may be omitted by specifying the
! 161: ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
! 162: **
! 163: ** See also: SQL functions [sqlite_compileoption_used()] and
! 164: ** [sqlite_compileoption_get()] and the [compile_options pragma].
! 165: */
! 166: #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
! 167: int sqlite3_compileoption_used(const char *zOptName);
! 168: const char *sqlite3_compileoption_get(int N);
! 169: #endif
! 170:
! 171: /*
! 172: ** CAPI3REF: Test To See If The Library Is Threadsafe
! 173: **
! 174: ** ^The sqlite3_threadsafe() function returns zero if and only if
! 175: ** SQLite was compiled with mutexing code omitted due to the
! 176: ** [SQLITE_THREADSAFE] compile-time option being set to 0.
! 177: **
! 178: ** SQLite can be compiled with or without mutexes. When
! 179: ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
! 180: ** are enabled and SQLite is threadsafe. When the
! 181: ** [SQLITE_THREADSAFE] macro is 0,
! 182: ** the mutexes are omitted. Without the mutexes, it is not safe
! 183: ** to use SQLite concurrently from more than one thread.
! 184: **
! 185: ** Enabling mutexes incurs a measurable performance penalty.
! 186: ** So if speed is of utmost importance, it makes sense to disable
! 187: ** the mutexes. But for maximum safety, mutexes should be enabled.
! 188: ** ^The default behavior is for mutexes to be enabled.
! 189: **
! 190: ** This interface can be used by an application to make sure that the
! 191: ** version of SQLite that it is linking against was compiled with
! 192: ** the desired setting of the [SQLITE_THREADSAFE] macro.
! 193: **
! 194: ** This interface only reports on the compile-time mutex setting
! 195: ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
! 196: ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
! 197: ** can be fully or partially disabled using a call to [sqlite3_config()]
! 198: ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
! 199: ** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the
! 200: ** sqlite3_threadsafe() function shows only the compile-time setting of
! 201: ** thread safety, not any run-time changes to that setting made by
! 202: ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
! 203: ** is unchanged by calls to sqlite3_config().)^
! 204: **
! 205: ** See the [threading mode] documentation for additional information.
! 206: */
! 207: int sqlite3_threadsafe(void);
! 208:
! 209: /*
! 210: ** CAPI3REF: Database Connection Handle
! 211: ** KEYWORDS: {database connection} {database connections}
! 212: **
! 213: ** Each open SQLite database is represented by a pointer to an instance of
! 214: ** the opaque structure named "sqlite3". It is useful to think of an sqlite3
! 215: ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
! 216: ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
! 217: ** is its destructor. There are many other interfaces (such as
! 218: ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
! 219: ** [sqlite3_busy_timeout()] to name but three) that are methods on an
! 220: ** sqlite3 object.
! 221: */
! 222: typedef struct sqlite3 sqlite3;
! 223:
! 224: /*
! 225: ** CAPI3REF: 64-Bit Integer Types
! 226: ** KEYWORDS: sqlite_int64 sqlite_uint64
! 227: **
! 228: ** Because there is no cross-platform way to specify 64-bit integer types
! 229: ** SQLite includes typedefs for 64-bit signed and unsigned integers.
! 230: **
! 231: ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
! 232: ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
! 233: ** compatibility only.
! 234: **
! 235: ** ^The sqlite3_int64 and sqlite_int64 types can store integer values
! 236: ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
! 237: ** sqlite3_uint64 and sqlite_uint64 types can store integer values
! 238: ** between 0 and +18446744073709551615 inclusive.
! 239: */
! 240: #ifdef SQLITE_INT64_TYPE
! 241: typedef SQLITE_INT64_TYPE sqlite_int64;
! 242: typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
! 243: #elif defined(_MSC_VER) || defined(__BORLANDC__)
! 244: typedef __int64 sqlite_int64;
! 245: typedef unsigned __int64 sqlite_uint64;
! 246: #else
! 247: typedef long long int sqlite_int64;
! 248: typedef unsigned long long int sqlite_uint64;
! 249: #endif
! 250: typedef sqlite_int64 sqlite3_int64;
! 251: typedef sqlite_uint64 sqlite3_uint64;
! 252:
! 253: /*
! 254: ** If compiling for a processor that lacks floating point support,
! 255: ** substitute integer for floating-point.
! 256: */
! 257: #ifdef SQLITE_OMIT_FLOATING_POINT
! 258: # define double sqlite3_int64
! 259: #endif
! 260:
! 261: /*
! 262: ** CAPI3REF: Closing A Database Connection
! 263: **
! 264: ** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
! 265: ** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
! 266: ** successfully destroyed and all associated resources are deallocated.
! 267: **
! 268: ** Applications must [sqlite3_finalize | finalize] all [prepared statements]
! 269: ** and [sqlite3_blob_close | close] all [BLOB handles] associated with
! 270: ** the [sqlite3] object prior to attempting to close the object. ^If
! 271: ** sqlite3_close() is called on a [database connection] that still has
! 272: ** outstanding [prepared statements] or [BLOB handles], then it returns
! 273: ** SQLITE_BUSY.
! 274: **
! 275: ** ^If [sqlite3_close()] is invoked while a transaction is open,
! 276: ** the transaction is automatically rolled back.
! 277: **
! 278: ** The C parameter to [sqlite3_close(C)] must be either a NULL
! 279: ** pointer or an [sqlite3] object pointer obtained
! 280: ** from [sqlite3_open()], [sqlite3_open16()], or
! 281: ** [sqlite3_open_v2()], and not previously closed.
! 282: ** ^Calling sqlite3_close() with a NULL pointer argument is a
! 283: ** harmless no-op.
! 284: */
! 285: int sqlite3_close(sqlite3 *);
! 286:
! 287: /*
! 288: ** The type for a callback function.
! 289: ** This is legacy and deprecated. It is included for historical
! 290: ** compatibility and is not documented.
! 291: */
! 292: typedef int (*sqlite3_callback)(void*,int,char**, char**);
! 293:
! 294: /*
! 295: ** CAPI3REF: One-Step Query Execution Interface
! 296: **
! 297: ** The sqlite3_exec() interface is a convenience wrapper around
! 298: ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
! 299: ** that allows an application to run multiple statements of SQL
! 300: ** without having to use a lot of C code.
! 301: **
! 302: ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
! 303: ** semicolon-separate SQL statements passed into its 2nd argument,
! 304: ** in the context of the [database connection] passed in as its 1st
! 305: ** argument. ^If the callback function of the 3rd argument to
! 306: ** sqlite3_exec() is not NULL, then it is invoked for each result row
! 307: ** coming out of the evaluated SQL statements. ^The 4th argument to
! 308: ** sqlite3_exec() is relayed through to the 1st argument of each
! 309: ** callback invocation. ^If the callback pointer to sqlite3_exec()
! 310: ** is NULL, then no callback is ever invoked and result rows are
! 311: ** ignored.
! 312: **
! 313: ** ^If an error occurs while evaluating the SQL statements passed into
! 314: ** sqlite3_exec(), then execution of the current statement stops and
! 315: ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
! 316: ** is not NULL then any error message is written into memory obtained
! 317: ** from [sqlite3_malloc()] and passed back through the 5th parameter.
! 318: ** To avoid memory leaks, the application should invoke [sqlite3_free()]
! 319: ** on error message strings returned through the 5th parameter of
! 320: ** of sqlite3_exec() after the error message string is no longer needed.
! 321: ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
! 322: ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
! 323: ** NULL before returning.
! 324: **
! 325: ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
! 326: ** routine returns SQLITE_ABORT without invoking the callback again and
! 327: ** without running any subsequent SQL statements.
! 328: **
! 329: ** ^The 2nd argument to the sqlite3_exec() callback function is the
! 330: ** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
! 331: ** callback is an array of pointers to strings obtained as if from
! 332: ** [sqlite3_column_text()], one for each column. ^If an element of a
! 333: ** result row is NULL then the corresponding string pointer for the
! 334: ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
! 335: ** sqlite3_exec() callback is an array of pointers to strings where each
! 336: ** entry represents the name of corresponding result column as obtained
! 337: ** from [sqlite3_column_name()].
! 338: **
! 339: ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
! 340: ** to an empty string, or a pointer that contains only whitespace and/or
! 341: ** SQL comments, then no SQL statements are evaluated and the database
! 342: ** is not changed.
! 343: **
! 344: ** Restrictions:
! 345: **
! 346: ** <ul>
! 347: ** <li> The application must insure that the 1st parameter to sqlite3_exec()
! 348: ** is a valid and open [database connection].
! 349: ** <li> The application must not close [database connection] specified by
! 350: ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
! 351: ** <li> The application must not modify the SQL statement text passed into
! 352: ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
! 353: ** </ul>
! 354: */
! 355: int sqlite3_exec(
! 356: sqlite3*, /* An open database */
! 357: const char *sql, /* SQL to be evaluated */
! 358: int (*callback)(void*,int,char**,char**), /* Callback function */
! 359: void *, /* 1st argument to callback */
! 360: char **errmsg /* Error msg written here */
! 361: );
! 362:
! 363: /*
! 364: ** CAPI3REF: Result Codes
! 365: ** KEYWORDS: SQLITE_OK {error code} {error codes}
! 366: ** KEYWORDS: {result code} {result codes}
! 367: **
! 368: ** Many SQLite functions return an integer result code from the set shown
! 369: ** here in order to indicate success or failure.
! 370: **
! 371: ** New error codes may be added in future versions of SQLite.
! 372: **
! 373: ** See also: [SQLITE_IOERR_READ | extended result codes],
! 374: ** [sqlite3_vtab_on_conflict()] [SQLITE_ROLLBACK | result codes].
! 375: */
! 376: #define SQLITE_OK 0 /* Successful result */
! 377: /* beginning-of-error-codes */
! 378: #define SQLITE_ERROR 1 /* SQL error or missing database */
! 379: #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
! 380: #define SQLITE_PERM 3 /* Access permission denied */
! 381: #define SQLITE_ABORT 4 /* Callback routine requested an abort */
! 382: #define SQLITE_BUSY 5 /* The database file is locked */
! 383: #define SQLITE_LOCKED 6 /* A table in the database is locked */
! 384: #define SQLITE_NOMEM 7 /* A malloc() failed */
! 385: #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
! 386: #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
! 387: #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
! 388: #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
! 389: #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
! 390: #define SQLITE_FULL 13 /* Insertion failed because database is full */
! 391: #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
! 392: #define SQLITE_PROTOCOL 15 /* Database lock protocol error */
! 393: #define SQLITE_EMPTY 16 /* Database is empty */
! 394: #define SQLITE_SCHEMA 17 /* The database schema changed */
! 395: #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
! 396: #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
! 397: #define SQLITE_MISMATCH 20 /* Data type mismatch */
! 398: #define SQLITE_MISUSE 21 /* Library used incorrectly */
! 399: #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
! 400: #define SQLITE_AUTH 23 /* Authorization denied */
! 401: #define SQLITE_FORMAT 24 /* Auxiliary database format error */
! 402: #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
! 403: #define SQLITE_NOTADB 26 /* File opened that is not a database file */
! 404: #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
! 405: #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
! 406: /* end-of-error-codes */
! 407:
! 408: /*
! 409: ** CAPI3REF: Extended Result Codes
! 410: ** KEYWORDS: {extended error code} {extended error codes}
! 411: ** KEYWORDS: {extended result code} {extended result codes}
! 412: **
! 413: ** In its default configuration, SQLite API routines return one of 26 integer
! 414: ** [SQLITE_OK | result codes]. However, experience has shown that many of
! 415: ** these result codes are too coarse-grained. They do not provide as
! 416: ** much information about problems as programmers might like. In an effort to
! 417: ** address this, newer versions of SQLite (version 3.3.8 and later) include
! 418: ** support for additional result codes that provide more detailed information
! 419: ** about errors. The extended result codes are enabled or disabled
! 420: ** on a per database connection basis using the
! 421: ** [sqlite3_extended_result_codes()] API.
! 422: **
! 423: ** Some of the available extended result codes are listed here.
! 424: ** One may expect the number of extended result codes will be expand
! 425: ** over time. Software that uses extended result codes should expect
! 426: ** to see new result codes in future releases of SQLite.
! 427: **
! 428: ** The SQLITE_OK result code will never be extended. It will always
! 429: ** be exactly zero.
! 430: */
! 431: #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
! 432: #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
! 433: #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
! 434: #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
! 435: #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
! 436: #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
! 437: #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
! 438: #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
! 439: #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
! 440: #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
! 441: #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
! 442: #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
! 443: #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
! 444: #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
! 445: #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
! 446: #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
! 447: #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
! 448: #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
! 449: #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
! 450: #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
! 451: #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
! 452: #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
! 453: #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
! 454: #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
! 455: #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
! 456: #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
! 457: #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
! 458: #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
! 459:
! 460: /*
! 461: ** CAPI3REF: Flags For File Open Operations
! 462: **
! 463: ** These bit values are intended for use in the
! 464: ** 3rd parameter to the [sqlite3_open_v2()] interface and
! 465: ** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
! 466: */
! 467: #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
! 468: #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
! 469: #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
! 470: #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
! 471: #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
! 472: #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
! 473: #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
! 474: #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
! 475: #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
! 476: #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
! 477: #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
! 478: #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
! 479: #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
! 480: #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
! 481: #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
! 482: #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
! 483: #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
! 484: #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
! 485: #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
! 486:
! 487: /* Reserved: 0x00F00000 */
! 488:
! 489: /*
! 490: ** CAPI3REF: Device Characteristics
! 491: **
! 492: ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
! 493: ** object returns an integer which is a vector of the these
! 494: ** bit values expressing I/O characteristics of the mass storage
! 495: ** device that holds the file that the [sqlite3_io_methods]
! 496: ** refers to.
! 497: **
! 498: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
! 499: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
! 500: ** mean that writes of blocks that are nnn bytes in size and
! 501: ** are aligned to an address which is an integer multiple of
! 502: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
! 503: ** that when data is appended to a file, the data is appended
! 504: ** first then the size of the file is extended, never the other
! 505: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
! 506: ** information is written to disk in the same order as calls
! 507: ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
! 508: ** after reboot following a crash or power loss, the only bytes in a
! 509: ** file that were written at the application level might have changed
! 510: ** and that adjacent bytes, even bytes within the same sector are
! 511: ** guaranteed to be unchanged.
! 512: */
! 513: #define SQLITE_IOCAP_ATOMIC 0x00000001
! 514: #define SQLITE_IOCAP_ATOMIC512 0x00000002
! 515: #define SQLITE_IOCAP_ATOMIC1K 0x00000004
! 516: #define SQLITE_IOCAP_ATOMIC2K 0x00000008
! 517: #define SQLITE_IOCAP_ATOMIC4K 0x00000010
! 518: #define SQLITE_IOCAP_ATOMIC8K 0x00000020
! 519: #define SQLITE_IOCAP_ATOMIC16K 0x00000040
! 520: #define SQLITE_IOCAP_ATOMIC32K 0x00000080
! 521: #define SQLITE_IOCAP_ATOMIC64K 0x00000100
! 522: #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
! 523: #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
! 524: #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
! 525: #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
! 526:
! 527: /*
! 528: ** CAPI3REF: File Locking Levels
! 529: **
! 530: ** SQLite uses one of these integer values as the second
! 531: ** argument to calls it makes to the xLock() and xUnlock() methods
! 532: ** of an [sqlite3_io_methods] object.
! 533: */
! 534: #define SQLITE_LOCK_NONE 0
! 535: #define SQLITE_LOCK_SHARED 1
! 536: #define SQLITE_LOCK_RESERVED 2
! 537: #define SQLITE_LOCK_PENDING 3
! 538: #define SQLITE_LOCK_EXCLUSIVE 4
! 539:
! 540: /*
! 541: ** CAPI3REF: Synchronization Type Flags
! 542: **
! 543: ** When SQLite invokes the xSync() method of an
! 544: ** [sqlite3_io_methods] object it uses a combination of
! 545: ** these integer values as the second argument.
! 546: **
! 547: ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
! 548: ** sync operation only needs to flush data to mass storage. Inode
! 549: ** information need not be flushed. If the lower four bits of the flag
! 550: ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
! 551: ** If the lower four bits equal SQLITE_SYNC_FULL, that means
! 552: ** to use Mac OS X style fullsync instead of fsync().
! 553: **
! 554: ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
! 555: ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
! 556: ** settings. The [synchronous pragma] determines when calls to the
! 557: ** xSync VFS method occur and applies uniformly across all platforms.
! 558: ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
! 559: ** energetic or rigorous or forceful the sync operations are and
! 560: ** only make a difference on Mac OSX for the default SQLite code.
! 561: ** (Third-party VFS implementations might also make the distinction
! 562: ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
! 563: ** operating systems natively supported by SQLite, only Mac OSX
! 564: ** cares about the difference.)
! 565: */
! 566: #define SQLITE_SYNC_NORMAL 0x00002
! 567: #define SQLITE_SYNC_FULL 0x00003
! 568: #define SQLITE_SYNC_DATAONLY 0x00010
! 569:
! 570: /*
! 571: ** CAPI3REF: OS Interface Open File Handle
! 572: **
! 573: ** An [sqlite3_file] object represents an open file in the
! 574: ** [sqlite3_vfs | OS interface layer]. Individual OS interface
! 575: ** implementations will
! 576: ** want to subclass this object by appending additional fields
! 577: ** for their own use. The pMethods entry is a pointer to an
! 578: ** [sqlite3_io_methods] object that defines methods for performing
! 579: ** I/O operations on the open file.
! 580: */
! 581: typedef struct sqlite3_file sqlite3_file;
! 582: struct sqlite3_file {
! 583: const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
! 584: };
! 585:
! 586: /*
! 587: ** CAPI3REF: OS Interface File Virtual Methods Object
! 588: **
! 589: ** Every file opened by the [sqlite3_vfs.xOpen] method populates an
! 590: ** [sqlite3_file] object (or, more commonly, a subclass of the
! 591: ** [sqlite3_file] object) with a pointer to an instance of this object.
! 592: ** This object defines the methods used to perform various operations
! 593: ** against the open file represented by the [sqlite3_file] object.
! 594: **
! 595: ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
! 596: ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
! 597: ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
! 598: ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
! 599: ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
! 600: ** to NULL.
! 601: **
! 602: ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
! 603: ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
! 604: ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
! 605: ** flag may be ORed in to indicate that only the data of the file
! 606: ** and not its inode needs to be synced.
! 607: **
! 608: ** The integer values to xLock() and xUnlock() are one of
! 609: ** <ul>
! 610: ** <li> [SQLITE_LOCK_NONE],
! 611: ** <li> [SQLITE_LOCK_SHARED],
! 612: ** <li> [SQLITE_LOCK_RESERVED],
! 613: ** <li> [SQLITE_LOCK_PENDING], or
! 614: ** <li> [SQLITE_LOCK_EXCLUSIVE].
! 615: ** </ul>
! 616: ** xLock() increases the lock. xUnlock() decreases the lock.
! 617: ** The xCheckReservedLock() method checks whether any database connection,
! 618: ** either in this process or in some other process, is holding a RESERVED,
! 619: ** PENDING, or EXCLUSIVE lock on the file. It returns true
! 620: ** if such a lock exists and false otherwise.
! 621: **
! 622: ** The xFileControl() method is a generic interface that allows custom
! 623: ** VFS implementations to directly control an open file using the
! 624: ** [sqlite3_file_control()] interface. The second "op" argument is an
! 625: ** integer opcode. The third argument is a generic pointer intended to
! 626: ** point to a structure that may contain arguments or space in which to
! 627: ** write return values. Potential uses for xFileControl() might be
! 628: ** functions to enable blocking locks with timeouts, to change the
! 629: ** locking strategy (for example to use dot-file locks), to inquire
! 630: ** about the status of a lock, or to break stale locks. The SQLite
! 631: ** core reserves all opcodes less than 100 for its own use.
! 632: ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
! 633: ** Applications that define a custom xFileControl method should use opcodes
! 634: ** greater than 100 to avoid conflicts. VFS implementations should
! 635: ** return [SQLITE_NOTFOUND] for file control opcodes that they do not
! 636: ** recognize.
! 637: **
! 638: ** The xSectorSize() method returns the sector size of the
! 639: ** device that underlies the file. The sector size is the
! 640: ** minimum write that can be performed without disturbing
! 641: ** other bytes in the file. The xDeviceCharacteristics()
! 642: ** method returns a bit vector describing behaviors of the
! 643: ** underlying device:
! 644: **
! 645: ** <ul>
! 646: ** <li> [SQLITE_IOCAP_ATOMIC]
! 647: ** <li> [SQLITE_IOCAP_ATOMIC512]
! 648: ** <li> [SQLITE_IOCAP_ATOMIC1K]
! 649: ** <li> [SQLITE_IOCAP_ATOMIC2K]
! 650: ** <li> [SQLITE_IOCAP_ATOMIC4K]
! 651: ** <li> [SQLITE_IOCAP_ATOMIC8K]
! 652: ** <li> [SQLITE_IOCAP_ATOMIC16K]
! 653: ** <li> [SQLITE_IOCAP_ATOMIC32K]
! 654: ** <li> [SQLITE_IOCAP_ATOMIC64K]
! 655: ** <li> [SQLITE_IOCAP_SAFE_APPEND]
! 656: ** <li> [SQLITE_IOCAP_SEQUENTIAL]
! 657: ** </ul>
! 658: **
! 659: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
! 660: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
! 661: ** mean that writes of blocks that are nnn bytes in size and
! 662: ** are aligned to an address which is an integer multiple of
! 663: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
! 664: ** that when data is appended to a file, the data is appended
! 665: ** first then the size of the file is extended, never the other
! 666: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
! 667: ** information is written to disk in the same order as calls
! 668: ** to xWrite().
! 669: **
! 670: ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
! 671: ** in the unread portions of the buffer with zeros. A VFS that
! 672: ** fails to zero-fill short reads might seem to work. However,
! 673: ** failure to zero-fill short reads will eventually lead to
! 674: ** database corruption.
! 675: */
! 676: typedef struct sqlite3_io_methods sqlite3_io_methods;
! 677: struct sqlite3_io_methods {
! 678: int iVersion;
! 679: int (*xClose)(sqlite3_file*);
! 680: int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
! 681: int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
! 682: int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
! 683: int (*xSync)(sqlite3_file*, int flags);
! 684: int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
! 685: int (*xLock)(sqlite3_file*, int);
! 686: int (*xUnlock)(sqlite3_file*, int);
! 687: int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
! 688: int (*xFileControl)(sqlite3_file*, int op, void *pArg);
! 689: int (*xSectorSize)(sqlite3_file*);
! 690: int (*xDeviceCharacteristics)(sqlite3_file*);
! 691: /* Methods above are valid for version 1 */
! 692: int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
! 693: int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
! 694: void (*xShmBarrier)(sqlite3_file*);
! 695: int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
! 696: /* Methods above are valid for version 2 */
! 697: /* Additional methods may be added in future releases */
! 698: };
! 699:
! 700: /*
! 701: ** CAPI3REF: Standard File Control Opcodes
! 702: **
! 703: ** These integer constants are opcodes for the xFileControl method
! 704: ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
! 705: ** interface.
! 706: **
! 707: ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
! 708: ** opcode causes the xFileControl method to write the current state of
! 709: ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
! 710: ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
! 711: ** into an integer that the pArg argument points to. This capability
! 712: ** is used during testing and only needs to be supported when SQLITE_TEST
! 713: ** is defined.
! 714: **
! 715: ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
! 716: ** layer a hint of how large the database file will grow to be during the
! 717: ** current transaction. This hint is not guaranteed to be accurate but it
! 718: ** is often close. The underlying VFS might choose to preallocate database
! 719: ** file space based on this hint in order to help writes to the database
! 720: ** file run faster.
! 721: **
! 722: ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
! 723: ** extends and truncates the database file in chunks of a size specified
! 724: ** by the user. The fourth argument to [sqlite3_file_control()] should
! 725: ** point to an integer (type int) containing the new chunk-size to use
! 726: ** for the nominated database. Allocating database file space in large
! 727: ** chunks (say 1MB at a time), may reduce file-system fragmentation and
! 728: ** improve performance on some systems.
! 729: **
! 730: ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
! 731: ** to the [sqlite3_file] object associated with a particular database
! 732: ** connection. See the [sqlite3_file_control()] documentation for
! 733: ** additional information.
! 734: **
! 735: ** ^(The [SQLITE_FCNTL_SYNC_OMITTED] opcode is generated internally by
! 736: ** SQLite and sent to all VFSes in place of a call to the xSync method
! 737: ** when the database connection has [PRAGMA synchronous] set to OFF.)^
! 738: ** Some specialized VFSes need this signal in order to operate correctly
! 739: ** when [PRAGMA synchronous | PRAGMA synchronous=OFF] is set, but most
! 740: ** VFSes do not need this signal and should silently ignore this opcode.
! 741: ** Applications should not call [sqlite3_file_control()] with this
! 742: ** opcode as doing so may disrupt the operation of the specialized VFSes
! 743: ** that do require it.
! 744: **
! 745: ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
! 746: ** retry counts and intervals for certain disk I/O operations for the
! 747: ** windows [VFS] in order to provide robustness in the presence of
! 748: ** anti-virus programs. By default, the windows VFS will retry file read,
! 749: ** file write, and file delete operations up to 10 times, with a delay
! 750: ** of 25 milliseconds before the first retry and with the delay increasing
! 751: ** by an additional 25 milliseconds with each subsequent retry. This
! 752: ** opcode allows these two values (10 retries and 25 milliseconds of delay)
! 753: ** to be adjusted. The values are changed for all database connections
! 754: ** within the same process. The argument is a pointer to an array of two
! 755: ** integers where the first integer i the new retry count and the second
! 756: ** integer is the delay. If either integer is negative, then the setting
! 757: ** is not changed but instead the prior value of that setting is written
! 758: ** into the array entry, allowing the current retry settings to be
! 759: ** interrogated. The zDbName parameter is ignored.
! 760: **
! 761: ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
! 762: ** persistent [WAL | Write AHead Log] setting. By default, the auxiliary
! 763: ** write ahead log and shared memory files used for transaction control
! 764: ** are automatically deleted when the latest connection to the database
! 765: ** closes. Setting persistent WAL mode causes those files to persist after
! 766: ** close. Persisting the files is useful when other processes that do not
! 767: ** have write permission on the directory containing the database file want
! 768: ** to read the database file, as the WAL and shared memory files must exist
! 769: ** in order for the database to be readable. The fourth parameter to
! 770: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
! 771: ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
! 772: ** WAL mode. If the integer is -1, then it is overwritten with the current
! 773: ** WAL persistence setting.
! 774: **
! 775: ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
! 776: ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
! 777: ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
! 778: ** xDeviceCharacteristics methods. The fourth parameter to
! 779: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
! 780: ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
! 781: ** mode. If the integer is -1, then it is overwritten with the current
! 782: ** zero-damage mode setting.
! 783: **
! 784: ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
! 785: ** a write transaction to indicate that, unless it is rolled back for some
! 786: ** reason, the entire database file will be overwritten by the current
! 787: ** transaction. This is used by VACUUM operations.
! 788: **
! 789: ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
! 790: ** all [VFSes] in the VFS stack. The names are of all VFS shims and the
! 791: ** final bottom-level VFS are written into memory obtained from
! 792: ** [sqlite3_malloc()] and the result is stored in the char* variable
! 793: ** that the fourth parameter of [sqlite3_file_control()] points to.
! 794: ** The caller is responsible for freeing the memory when done. As with
! 795: ** all file-control actions, there is no guarantee that this will actually
! 796: ** do anything. Callers should initialize the char* variable to a NULL
! 797: ** pointer in case this file-control is not implemented. This file-control
! 798: ** is intended for diagnostic use only.
! 799: */
! 800: #define SQLITE_FCNTL_LOCKSTATE 1
! 801: #define SQLITE_GET_LOCKPROXYFILE 2
! 802: #define SQLITE_SET_LOCKPROXYFILE 3
! 803: #define SQLITE_LAST_ERRNO 4
! 804: #define SQLITE_FCNTL_SIZE_HINT 5
! 805: #define SQLITE_FCNTL_CHUNK_SIZE 6
! 806: #define SQLITE_FCNTL_FILE_POINTER 7
! 807: #define SQLITE_FCNTL_SYNC_OMITTED 8
! 808: #define SQLITE_FCNTL_WIN32_AV_RETRY 9
! 809: #define SQLITE_FCNTL_PERSIST_WAL 10
! 810: #define SQLITE_FCNTL_OVERWRITE 11
! 811: #define SQLITE_FCNTL_VFSNAME 12
! 812: #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
! 813:
! 814: /*
! 815: ** CAPI3REF: Mutex Handle
! 816: **
! 817: ** The mutex module within SQLite defines [sqlite3_mutex] to be an
! 818: ** abstract type for a mutex object. The SQLite core never looks
! 819: ** at the internal representation of an [sqlite3_mutex]. It only
! 820: ** deals with pointers to the [sqlite3_mutex] object.
! 821: **
! 822: ** Mutexes are created using [sqlite3_mutex_alloc()].
! 823: */
! 824: typedef struct sqlite3_mutex sqlite3_mutex;
! 825:
! 826: /*
! 827: ** CAPI3REF: OS Interface Object
! 828: **
! 829: ** An instance of the sqlite3_vfs object defines the interface between
! 830: ** the SQLite core and the underlying operating system. The "vfs"
! 831: ** in the name of the object stands for "virtual file system". See
! 832: ** the [VFS | VFS documentation] for further information.
! 833: **
! 834: ** The value of the iVersion field is initially 1 but may be larger in
! 835: ** future versions of SQLite. Additional fields may be appended to this
! 836: ** object when the iVersion value is increased. Note that the structure
! 837: ** of the sqlite3_vfs object changes in the transaction between
! 838: ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
! 839: ** modified.
! 840: **
! 841: ** The szOsFile field is the size of the subclassed [sqlite3_file]
! 842: ** structure used by this VFS. mxPathname is the maximum length of
! 843: ** a pathname in this VFS.
! 844: **
! 845: ** Registered sqlite3_vfs objects are kept on a linked list formed by
! 846: ** the pNext pointer. The [sqlite3_vfs_register()]
! 847: ** and [sqlite3_vfs_unregister()] interfaces manage this list
! 848: ** in a thread-safe way. The [sqlite3_vfs_find()] interface
! 849: ** searches the list. Neither the application code nor the VFS
! 850: ** implementation should use the pNext pointer.
! 851: **
! 852: ** The pNext field is the only field in the sqlite3_vfs
! 853: ** structure that SQLite will ever modify. SQLite will only access
! 854: ** or modify this field while holding a particular static mutex.
! 855: ** The application should never modify anything within the sqlite3_vfs
! 856: ** object once the object has been registered.
! 857: **
! 858: ** The zName field holds the name of the VFS module. The name must
! 859: ** be unique across all VFS modules.
! 860: **
! 861: ** [[sqlite3_vfs.xOpen]]
! 862: ** ^SQLite guarantees that the zFilename parameter to xOpen
! 863: ** is either a NULL pointer or string obtained
! 864: ** from xFullPathname() with an optional suffix added.
! 865: ** ^If a suffix is added to the zFilename parameter, it will
! 866: ** consist of a single "-" character followed by no more than
! 867: ** 11 alphanumeric and/or "-" characters.
! 868: ** ^SQLite further guarantees that
! 869: ** the string will be valid and unchanged until xClose() is
! 870: ** called. Because of the previous sentence,
! 871: ** the [sqlite3_file] can safely store a pointer to the
! 872: ** filename if it needs to remember the filename for some reason.
! 873: ** If the zFilename parameter to xOpen is a NULL pointer then xOpen
! 874: ** must invent its own temporary name for the file. ^Whenever the
! 875: ** xFilename parameter is NULL it will also be the case that the
! 876: ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
! 877: **
! 878: ** The flags argument to xOpen() includes all bits set in
! 879: ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
! 880: ** or [sqlite3_open16()] is used, then flags includes at least
! 881: ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
! 882: ** If xOpen() opens a file read-only then it sets *pOutFlags to
! 883: ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
! 884: **
! 885: ** ^(SQLite will also add one of the following flags to the xOpen()
! 886: ** call, depending on the object being opened:
! 887: **
! 888: ** <ul>
! 889: ** <li> [SQLITE_OPEN_MAIN_DB]
! 890: ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
! 891: ** <li> [SQLITE_OPEN_TEMP_DB]
! 892: ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
! 893: ** <li> [SQLITE_OPEN_TRANSIENT_DB]
! 894: ** <li> [SQLITE_OPEN_SUBJOURNAL]
! 895: ** <li> [SQLITE_OPEN_MASTER_JOURNAL]
! 896: ** <li> [SQLITE_OPEN_WAL]
! 897: ** </ul>)^
! 898: **
! 899: ** The file I/O implementation can use the object type flags to
! 900: ** change the way it deals with files. For example, an application
! 901: ** that does not care about crash recovery or rollback might make
! 902: ** the open of a journal file a no-op. Writes to this journal would
! 903: ** also be no-ops, and any attempt to read the journal would return
! 904: ** SQLITE_IOERR. Or the implementation might recognize that a database
! 905: ** file will be doing page-aligned sector reads and writes in a random
! 906: ** order and set up its I/O subsystem accordingly.
! 907: **
! 908: ** SQLite might also add one of the following flags to the xOpen method:
! 909: **
! 910: ** <ul>
! 911: ** <li> [SQLITE_OPEN_DELETEONCLOSE]
! 912: ** <li> [SQLITE_OPEN_EXCLUSIVE]
! 913: ** </ul>
! 914: **
! 915: ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
! 916: ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
! 917: ** will be set for TEMP databases and their journals, transient
! 918: ** databases, and subjournals.
! 919: **
! 920: ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
! 921: ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
! 922: ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
! 923: ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
! 924: ** SQLITE_OPEN_CREATE, is used to indicate that file should always
! 925: ** be created, and that it is an error if it already exists.
! 926: ** It is <i>not</i> used to indicate the file should be opened
! 927: ** for exclusive access.
! 928: **
! 929: ** ^At least szOsFile bytes of memory are allocated by SQLite
! 930: ** to hold the [sqlite3_file] structure passed as the third
! 931: ** argument to xOpen. The xOpen method does not have to
! 932: ** allocate the structure; it should just fill it in. Note that
! 933: ** the xOpen method must set the sqlite3_file.pMethods to either
! 934: ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
! 935: ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
! 936: ** element will be valid after xOpen returns regardless of the success
! 937: ** or failure of the xOpen call.
! 938: **
! 939: ** [[sqlite3_vfs.xAccess]]
! 940: ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
! 941: ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
! 942: ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
! 943: ** to test whether a file is at least readable. The file can be a
! 944: ** directory.
! 945: **
! 946: ** ^SQLite will always allocate at least mxPathname+1 bytes for the
! 947: ** output buffer xFullPathname. The exact size of the output buffer
! 948: ** is also passed as a parameter to both methods. If the output buffer
! 949: ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
! 950: ** handled as a fatal error by SQLite, vfs implementations should endeavor
! 951: ** to prevent this by setting mxPathname to a sufficiently large value.
! 952: **
! 953: ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
! 954: ** interfaces are not strictly a part of the filesystem, but they are
! 955: ** included in the VFS structure for completeness.
! 956: ** The xRandomness() function attempts to return nBytes bytes
! 957: ** of good-quality randomness into zOut. The return value is
! 958: ** the actual number of bytes of randomness obtained.
! 959: ** The xSleep() method causes the calling thread to sleep for at
! 960: ** least the number of microseconds given. ^The xCurrentTime()
! 961: ** method returns a Julian Day Number for the current date and time as
! 962: ** a floating point value.
! 963: ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
! 964: ** Day Number multiplied by 86400000 (the number of milliseconds in
! 965: ** a 24-hour day).
! 966: ** ^SQLite will use the xCurrentTimeInt64() method to get the current
! 967: ** date and time if that method is available (if iVersion is 2 or
! 968: ** greater and the function pointer is not NULL) and will fall back
! 969: ** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
! 970: **
! 971: ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
! 972: ** are not used by the SQLite core. These optional interfaces are provided
! 973: ** by some VFSes to facilitate testing of the VFS code. By overriding
! 974: ** system calls with functions under its control, a test program can
! 975: ** simulate faults and error conditions that would otherwise be difficult
! 976: ** or impossible to induce. The set of system calls that can be overridden
! 977: ** varies from one VFS to another, and from one version of the same VFS to the
! 978: ** next. Applications that use these interfaces must be prepared for any
! 979: ** or all of these interfaces to be NULL or for their behavior to change
! 980: ** from one release to the next. Applications must not attempt to access
! 981: ** any of these methods if the iVersion of the VFS is less than 3.
! 982: */
! 983: typedef struct sqlite3_vfs sqlite3_vfs;
! 984: typedef void (*sqlite3_syscall_ptr)(void);
! 985: struct sqlite3_vfs {
! 986: int iVersion; /* Structure version number (currently 3) */
! 987: int szOsFile; /* Size of subclassed sqlite3_file */
! 988: int mxPathname; /* Maximum file pathname length */
! 989: sqlite3_vfs *pNext; /* Next registered VFS */
! 990: const char *zName; /* Name of this virtual file system */
! 991: void *pAppData; /* Pointer to application-specific data */
! 992: int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
! 993: int flags, int *pOutFlags);
! 994: int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
! 995: int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
! 996: int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
! 997: void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
! 998: void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
! 999: void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
! 1000: void (*xDlClose)(sqlite3_vfs*, void*);
! 1001: int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
! 1002: int (*xSleep)(sqlite3_vfs*, int microseconds);
! 1003: int (*xCurrentTime)(sqlite3_vfs*, double*);
! 1004: int (*xGetLastError)(sqlite3_vfs*, int, char *);
! 1005: /*
! 1006: ** The methods above are in version 1 of the sqlite_vfs object
! 1007: ** definition. Those that follow are added in version 2 or later
! 1008: */
! 1009: int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
! 1010: /*
! 1011: ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
! 1012: ** Those below are for version 3 and greater.
! 1013: */
! 1014: int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
! 1015: sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
! 1016: const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
! 1017: /*
! 1018: ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
! 1019: ** New fields may be appended in figure versions. The iVersion
! 1020: ** value will increment whenever this happens.
! 1021: */
! 1022: };
! 1023:
! 1024: /*
! 1025: ** CAPI3REF: Flags for the xAccess VFS method
! 1026: **
! 1027: ** These integer constants can be used as the third parameter to
! 1028: ** the xAccess method of an [sqlite3_vfs] object. They determine
! 1029: ** what kind of permissions the xAccess method is looking for.
! 1030: ** With SQLITE_ACCESS_EXISTS, the xAccess method
! 1031: ** simply checks whether the file exists.
! 1032: ** With SQLITE_ACCESS_READWRITE, the xAccess method
! 1033: ** checks whether the named directory is both readable and writable
! 1034: ** (in other words, if files can be added, removed, and renamed within
! 1035: ** the directory).
! 1036: ** The SQLITE_ACCESS_READWRITE constant is currently used only by the
! 1037: ** [temp_store_directory pragma], though this could change in a future
! 1038: ** release of SQLite.
! 1039: ** With SQLITE_ACCESS_READ, the xAccess method
! 1040: ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
! 1041: ** currently unused, though it might be used in a future release of
! 1042: ** SQLite.
! 1043: */
! 1044: #define SQLITE_ACCESS_EXISTS 0
! 1045: #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
! 1046: #define SQLITE_ACCESS_READ 2 /* Unused */
! 1047:
! 1048: /*
! 1049: ** CAPI3REF: Flags for the xShmLock VFS method
! 1050: **
! 1051: ** These integer constants define the various locking operations
! 1052: ** allowed by the xShmLock method of [sqlite3_io_methods]. The
! 1053: ** following are the only legal combinations of flags to the
! 1054: ** xShmLock method:
! 1055: **
! 1056: ** <ul>
! 1057: ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
! 1058: ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
! 1059: ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
! 1060: ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
! 1061: ** </ul>
! 1062: **
! 1063: ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
! 1064: ** was given no the corresponding lock.
! 1065: **
! 1066: ** The xShmLock method can transition between unlocked and SHARED or
! 1067: ** between unlocked and EXCLUSIVE. It cannot transition between SHARED
! 1068: ** and EXCLUSIVE.
! 1069: */
! 1070: #define SQLITE_SHM_UNLOCK 1
! 1071: #define SQLITE_SHM_LOCK 2
! 1072: #define SQLITE_SHM_SHARED 4
! 1073: #define SQLITE_SHM_EXCLUSIVE 8
! 1074:
! 1075: /*
! 1076: ** CAPI3REF: Maximum xShmLock index
! 1077: **
! 1078: ** The xShmLock method on [sqlite3_io_methods] may use values
! 1079: ** between 0 and this upper bound as its "offset" argument.
! 1080: ** The SQLite core will never attempt to acquire or release a
! 1081: ** lock outside of this range
! 1082: */
! 1083: #define SQLITE_SHM_NLOCK 8
! 1084:
! 1085:
! 1086: /*
! 1087: ** CAPI3REF: Initialize The SQLite Library
! 1088: **
! 1089: ** ^The sqlite3_initialize() routine initializes the
! 1090: ** SQLite library. ^The sqlite3_shutdown() routine
! 1091: ** deallocates any resources that were allocated by sqlite3_initialize().
! 1092: ** These routines are designed to aid in process initialization and
! 1093: ** shutdown on embedded systems. Workstation applications using
! 1094: ** SQLite normally do not need to invoke either of these routines.
! 1095: **
! 1096: ** A call to sqlite3_initialize() is an "effective" call if it is
! 1097: ** the first time sqlite3_initialize() is invoked during the lifetime of
! 1098: ** the process, or if it is the first time sqlite3_initialize() is invoked
! 1099: ** following a call to sqlite3_shutdown(). ^(Only an effective call
! 1100: ** of sqlite3_initialize() does any initialization. All other calls
! 1101: ** are harmless no-ops.)^
! 1102: **
! 1103: ** A call to sqlite3_shutdown() is an "effective" call if it is the first
! 1104: ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
! 1105: ** an effective call to sqlite3_shutdown() does any deinitialization.
! 1106: ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
! 1107: **
! 1108: ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
! 1109: ** is not. The sqlite3_shutdown() interface must only be called from a
! 1110: ** single thread. All open [database connections] must be closed and all
! 1111: ** other SQLite resources must be deallocated prior to invoking
! 1112: ** sqlite3_shutdown().
! 1113: **
! 1114: ** Among other things, ^sqlite3_initialize() will invoke
! 1115: ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
! 1116: ** will invoke sqlite3_os_end().
! 1117: **
! 1118: ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
! 1119: ** ^If for some reason, sqlite3_initialize() is unable to initialize
! 1120: ** the library (perhaps it is unable to allocate a needed resource such
! 1121: ** as a mutex) it returns an [error code] other than [SQLITE_OK].
! 1122: **
! 1123: ** ^The sqlite3_initialize() routine is called internally by many other
! 1124: ** SQLite interfaces so that an application usually does not need to
! 1125: ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
! 1126: ** calls sqlite3_initialize() so the SQLite library will be automatically
! 1127: ** initialized when [sqlite3_open()] is called if it has not be initialized
! 1128: ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
! 1129: ** compile-time option, then the automatic calls to sqlite3_initialize()
! 1130: ** are omitted and the application must call sqlite3_initialize() directly
! 1131: ** prior to using any other SQLite interface. For maximum portability,
! 1132: ** it is recommended that applications always invoke sqlite3_initialize()
! 1133: ** directly prior to using any other SQLite interface. Future releases
! 1134: ** of SQLite may require this. In other words, the behavior exhibited
! 1135: ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
! 1136: ** default behavior in some future release of SQLite.
! 1137: **
! 1138: ** The sqlite3_os_init() routine does operating-system specific
! 1139: ** initialization of the SQLite library. The sqlite3_os_end()
! 1140: ** routine undoes the effect of sqlite3_os_init(). Typical tasks
! 1141: ** performed by these routines include allocation or deallocation
! 1142: ** of static resources, initialization of global variables,
! 1143: ** setting up a default [sqlite3_vfs] module, or setting up
! 1144: ** a default configuration using [sqlite3_config()].
! 1145: **
! 1146: ** The application should never invoke either sqlite3_os_init()
! 1147: ** or sqlite3_os_end() directly. The application should only invoke
! 1148: ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
! 1149: ** interface is called automatically by sqlite3_initialize() and
! 1150: ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
! 1151: ** implementations for sqlite3_os_init() and sqlite3_os_end()
! 1152: ** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
! 1153: ** When [custom builds | built for other platforms]
! 1154: ** (using the [SQLITE_OS_OTHER=1] compile-time
! 1155: ** option) the application must supply a suitable implementation for
! 1156: ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
! 1157: ** implementation of sqlite3_os_init() or sqlite3_os_end()
! 1158: ** must return [SQLITE_OK] on success and some other [error code] upon
! 1159: ** failure.
! 1160: */
! 1161: int sqlite3_initialize(void);
! 1162: int sqlite3_shutdown(void);
! 1163: int sqlite3_os_init(void);
! 1164: int sqlite3_os_end(void);
! 1165:
! 1166: /*
! 1167: ** CAPI3REF: Configuring The SQLite Library
! 1168: **
! 1169: ** The sqlite3_config() interface is used to make global configuration
! 1170: ** changes to SQLite in order to tune SQLite to the specific needs of
! 1171: ** the application. The default configuration is recommended for most
! 1172: ** applications and so this routine is usually not necessary. It is
! 1173: ** provided to support rare applications with unusual needs.
! 1174: **
! 1175: ** The sqlite3_config() interface is not threadsafe. The application
! 1176: ** must insure that no other SQLite interfaces are invoked by other
! 1177: ** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
! 1178: ** may only be invoked prior to library initialization using
! 1179: ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
! 1180: ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
! 1181: ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
! 1182: ** Note, however, that ^sqlite3_config() can be called as part of the
! 1183: ** implementation of an application-defined [sqlite3_os_init()].
! 1184: **
! 1185: ** The first argument to sqlite3_config() is an integer
! 1186: ** [configuration option] that determines
! 1187: ** what property of SQLite is to be configured. Subsequent arguments
! 1188: ** vary depending on the [configuration option]
! 1189: ** in the first argument.
! 1190: **
! 1191: ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
! 1192: ** ^If the option is unknown or SQLite is unable to set the option
! 1193: ** then this routine returns a non-zero [error code].
! 1194: */
! 1195: int sqlite3_config(int, ...);
! 1196:
! 1197: /*
! 1198: ** CAPI3REF: Configure database connections
! 1199: **
! 1200: ** The sqlite3_db_config() interface is used to make configuration
! 1201: ** changes to a [database connection]. The interface is similar to
! 1202: ** [sqlite3_config()] except that the changes apply to a single
! 1203: ** [database connection] (specified in the first argument).
! 1204: **
! 1205: ** The second argument to sqlite3_db_config(D,V,...) is the
! 1206: ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
! 1207: ** that indicates what aspect of the [database connection] is being configured.
! 1208: ** Subsequent arguments vary depending on the configuration verb.
! 1209: **
! 1210: ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
! 1211: ** the call is considered successful.
! 1212: */
! 1213: int sqlite3_db_config(sqlite3*, int op, ...);
! 1214:
! 1215: /*
! 1216: ** CAPI3REF: Memory Allocation Routines
! 1217: **
! 1218: ** An instance of this object defines the interface between SQLite
! 1219: ** and low-level memory allocation routines.
! 1220: **
! 1221: ** This object is used in only one place in the SQLite interface.
! 1222: ** A pointer to an instance of this object is the argument to
! 1223: ** [sqlite3_config()] when the configuration option is
! 1224: ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
! 1225: ** By creating an instance of this object
! 1226: ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
! 1227: ** during configuration, an application can specify an alternative
! 1228: ** memory allocation subsystem for SQLite to use for all of its
! 1229: ** dynamic memory needs.
! 1230: **
! 1231: ** Note that SQLite comes with several [built-in memory allocators]
! 1232: ** that are perfectly adequate for the overwhelming majority of applications
! 1233: ** and that this object is only useful to a tiny minority of applications
! 1234: ** with specialized memory allocation requirements. This object is
! 1235: ** also used during testing of SQLite in order to specify an alternative
! 1236: ** memory allocator that simulates memory out-of-memory conditions in
! 1237: ** order to verify that SQLite recovers gracefully from such
! 1238: ** conditions.
! 1239: **
! 1240: ** The xMalloc, xRealloc, and xFree methods must work like the
! 1241: ** malloc(), realloc() and free() functions from the standard C library.
! 1242: ** ^SQLite guarantees that the second argument to
! 1243: ** xRealloc is always a value returned by a prior call to xRoundup.
! 1244: **
! 1245: ** xSize should return the allocated size of a memory allocation
! 1246: ** previously obtained from xMalloc or xRealloc. The allocated size
! 1247: ** is always at least as big as the requested size but may be larger.
! 1248: **
! 1249: ** The xRoundup method returns what would be the allocated size of
! 1250: ** a memory allocation given a particular requested size. Most memory
! 1251: ** allocators round up memory allocations at least to the next multiple
! 1252: ** of 8. Some allocators round up to a larger multiple or to a power of 2.
! 1253: ** Every memory allocation request coming in through [sqlite3_malloc()]
! 1254: ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
! 1255: ** that causes the corresponding memory allocation to fail.
! 1256: **
! 1257: ** The xInit method initializes the memory allocator. (For example,
! 1258: ** it might allocate any require mutexes or initialize internal data
! 1259: ** structures. The xShutdown method is invoked (indirectly) by
! 1260: ** [sqlite3_shutdown()] and should deallocate any resources acquired
! 1261: ** by xInit. The pAppData pointer is used as the only parameter to
! 1262: ** xInit and xShutdown.
! 1263: **
! 1264: ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
! 1265: ** the xInit method, so the xInit method need not be threadsafe. The
! 1266: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
! 1267: ** not need to be threadsafe either. For all other methods, SQLite
! 1268: ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
! 1269: ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
! 1270: ** it is by default) and so the methods are automatically serialized.
! 1271: ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
! 1272: ** methods must be threadsafe or else make their own arrangements for
! 1273: ** serialization.
! 1274: **
! 1275: ** SQLite will never invoke xInit() more than once without an intervening
! 1276: ** call to xShutdown().
! 1277: */
! 1278: typedef struct sqlite3_mem_methods sqlite3_mem_methods;
! 1279: struct sqlite3_mem_methods {
! 1280: void *(*xMalloc)(int); /* Memory allocation function */
! 1281: void (*xFree)(void*); /* Free a prior allocation */
! 1282: void *(*xRealloc)(void*,int); /* Resize an allocation */
! 1283: int (*xSize)(void*); /* Return the size of an allocation */
! 1284: int (*xRoundup)(int); /* Round up request size to allocation size */
! 1285: int (*xInit)(void*); /* Initialize the memory allocator */
! 1286: void (*xShutdown)(void*); /* Deinitialize the memory allocator */
! 1287: void *pAppData; /* Argument to xInit() and xShutdown() */
! 1288: };
! 1289:
! 1290: /*
! 1291: ** CAPI3REF: Configuration Options
! 1292: ** KEYWORDS: {configuration option}
! 1293: **
! 1294: ** These constants are the available integer configuration options that
! 1295: ** can be passed as the first argument to the [sqlite3_config()] interface.
! 1296: **
! 1297: ** New configuration options may be added in future releases of SQLite.
! 1298: ** Existing configuration options might be discontinued. Applications
! 1299: ** should check the return code from [sqlite3_config()] to make sure that
! 1300: ** the call worked. The [sqlite3_config()] interface will return a
! 1301: ** non-zero [error code] if a discontinued or unsupported configuration option
! 1302: ** is invoked.
! 1303: **
! 1304: ** <dl>
! 1305: ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
! 1306: ** <dd>There are no arguments to this option. ^This option sets the
! 1307: ** [threading mode] to Single-thread. In other words, it disables
! 1308: ** all mutexing and puts SQLite into a mode where it can only be used
! 1309: ** by a single thread. ^If SQLite is compiled with
! 1310: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1311: ** it is not possible to change the [threading mode] from its default
! 1312: ** value of Single-thread and so [sqlite3_config()] will return
! 1313: ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
! 1314: ** configuration option.</dd>
! 1315: **
! 1316: ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
! 1317: ** <dd>There are no arguments to this option. ^This option sets the
! 1318: ** [threading mode] to Multi-thread. In other words, it disables
! 1319: ** mutexing on [database connection] and [prepared statement] objects.
! 1320: ** The application is responsible for serializing access to
! 1321: ** [database connections] and [prepared statements]. But other mutexes
! 1322: ** are enabled so that SQLite will be safe to use in a multi-threaded
! 1323: ** environment as long as no two threads attempt to use the same
! 1324: ** [database connection] at the same time. ^If SQLite is compiled with
! 1325: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1326: ** it is not possible to set the Multi-thread [threading mode] and
! 1327: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
! 1328: ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
! 1329: **
! 1330: ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
! 1331: ** <dd>There are no arguments to this option. ^This option sets the
! 1332: ** [threading mode] to Serialized. In other words, this option enables
! 1333: ** all mutexes including the recursive
! 1334: ** mutexes on [database connection] and [prepared statement] objects.
! 1335: ** In this mode (which is the default when SQLite is compiled with
! 1336: ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
! 1337: ** to [database connections] and [prepared statements] so that the
! 1338: ** application is free to use the same [database connection] or the
! 1339: ** same [prepared statement] in different threads at the same time.
! 1340: ** ^If SQLite is compiled with
! 1341: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1342: ** it is not possible to set the Serialized [threading mode] and
! 1343: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
! 1344: ** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
! 1345: **
! 1346: ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
! 1347: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1348: ** instance of the [sqlite3_mem_methods] structure. The argument specifies
! 1349: ** alternative low-level memory allocation routines to be used in place of
! 1350: ** the memory allocation routines built into SQLite.)^ ^SQLite makes
! 1351: ** its own private copy of the content of the [sqlite3_mem_methods] structure
! 1352: ** before the [sqlite3_config()] call returns.</dd>
! 1353: **
! 1354: ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
! 1355: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1356: ** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
! 1357: ** structure is filled with the currently defined memory allocation routines.)^
! 1358: ** This option can be used to overload the default memory allocation
! 1359: ** routines with a wrapper that simulations memory allocation failure or
! 1360: ** tracks memory usage, for example. </dd>
! 1361: **
! 1362: ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
! 1363: ** <dd> ^This option takes single argument of type int, interpreted as a
! 1364: ** boolean, which enables or disables the collection of memory allocation
! 1365: ** statistics. ^(When memory allocation statistics are disabled, the
! 1366: ** following SQLite interfaces become non-operational:
! 1367: ** <ul>
! 1368: ** <li> [sqlite3_memory_used()]
! 1369: ** <li> [sqlite3_memory_highwater()]
! 1370: ** <li> [sqlite3_soft_heap_limit64()]
! 1371: ** <li> [sqlite3_status()]
! 1372: ** </ul>)^
! 1373: ** ^Memory allocation statistics are enabled by default unless SQLite is
! 1374: ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
! 1375: ** allocation statistics are disabled by default.
! 1376: ** </dd>
! 1377: **
! 1378: ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
! 1379: ** <dd> ^This option specifies a static memory buffer that SQLite can use for
! 1380: ** scratch memory. There are three arguments: A pointer an 8-byte
! 1381: ** aligned memory buffer from which the scratch allocations will be
! 1382: ** drawn, the size of each scratch allocation (sz),
! 1383: ** and the maximum number of scratch allocations (N). The sz
! 1384: ** argument must be a multiple of 16.
! 1385: ** The first argument must be a pointer to an 8-byte aligned buffer
! 1386: ** of at least sz*N bytes of memory.
! 1387: ** ^SQLite will use no more than two scratch buffers per thread. So
! 1388: ** N should be set to twice the expected maximum number of threads.
! 1389: ** ^SQLite will never require a scratch buffer that is more than 6
! 1390: ** times the database page size. ^If SQLite needs needs additional
! 1391: ** scratch memory beyond what is provided by this configuration option, then
! 1392: ** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
! 1393: **
! 1394: ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
! 1395: ** <dd> ^This option specifies a static memory buffer that SQLite can use for
! 1396: ** the database page cache with the default page cache implementation.
! 1397: ** This configuration should not be used if an application-define page
! 1398: ** cache implementation is loaded using the SQLITE_CONFIG_PCACHE2 option.
! 1399: ** There are three arguments to this option: A pointer to 8-byte aligned
! 1400: ** memory, the size of each page buffer (sz), and the number of pages (N).
! 1401: ** The sz argument should be the size of the largest database page
! 1402: ** (a power of two between 512 and 32768) plus a little extra for each
! 1403: ** page header. ^The page header size is 20 to 40 bytes depending on
! 1404: ** the host architecture. ^It is harmless, apart from the wasted memory,
! 1405: ** to make sz a little too large. The first
! 1406: ** argument should point to an allocation of at least sz*N bytes of memory.
! 1407: ** ^SQLite will use the memory provided by the first argument to satisfy its
! 1408: ** memory needs for the first N pages that it adds to cache. ^If additional
! 1409: ** page cache memory is needed beyond what is provided by this option, then
! 1410: ** SQLite goes to [sqlite3_malloc()] for the additional storage space.
! 1411: ** The pointer in the first argument must
! 1412: ** be aligned to an 8-byte boundary or subsequent behavior of SQLite
! 1413: ** will be undefined.</dd>
! 1414: **
! 1415: ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
! 1416: ** <dd> ^This option specifies a static memory buffer that SQLite will use
! 1417: ** for all of its dynamic memory allocation needs beyond those provided
! 1418: ** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
! 1419: ** There are three arguments: An 8-byte aligned pointer to the memory,
! 1420: ** the number of bytes in the memory buffer, and the minimum allocation size.
! 1421: ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
! 1422: ** to using its default memory allocator (the system malloc() implementation),
! 1423: ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
! 1424: ** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
! 1425: ** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
! 1426: ** allocator is engaged to handle all of SQLites memory allocation needs.
! 1427: ** The first pointer (the memory pointer) must be aligned to an 8-byte
! 1428: ** boundary or subsequent behavior of SQLite will be undefined.
! 1429: ** The minimum allocation size is capped at 2**12. Reasonable values
! 1430: ** for the minimum allocation size are 2**5 through 2**8.</dd>
! 1431: **
! 1432: ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
! 1433: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1434: ** instance of the [sqlite3_mutex_methods] structure. The argument specifies
! 1435: ** alternative low-level mutex routines to be used in place
! 1436: ** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the
! 1437: ** content of the [sqlite3_mutex_methods] structure before the call to
! 1438: ** [sqlite3_config()] returns. ^If SQLite is compiled with
! 1439: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1440: ** the entire mutexing subsystem is omitted from the build and hence calls to
! 1441: ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
! 1442: ** return [SQLITE_ERROR].</dd>
! 1443: **
! 1444: ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
! 1445: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1446: ** instance of the [sqlite3_mutex_methods] structure. The
! 1447: ** [sqlite3_mutex_methods]
! 1448: ** structure is filled with the currently defined mutex routines.)^
! 1449: ** This option can be used to overload the default mutex allocation
! 1450: ** routines with a wrapper used to track mutex usage for performance
! 1451: ** profiling or testing, for example. ^If SQLite is compiled with
! 1452: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1453: ** the entire mutexing subsystem is omitted from the build and hence calls to
! 1454: ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
! 1455: ** return [SQLITE_ERROR].</dd>
! 1456: **
! 1457: ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
! 1458: ** <dd> ^(This option takes two arguments that determine the default
! 1459: ** memory allocation for the lookaside memory allocator on each
! 1460: ** [database connection]. The first argument is the
! 1461: ** size of each lookaside buffer slot and the second is the number of
! 1462: ** slots allocated to each database connection.)^ ^(This option sets the
! 1463: ** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
! 1464: ** verb to [sqlite3_db_config()] can be used to change the lookaside
! 1465: ** configuration on individual connections.)^ </dd>
! 1466: **
! 1467: ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
! 1468: ** <dd> ^(This option takes a single argument which is a pointer to
! 1469: ** an [sqlite3_pcache_methods2] object. This object specifies the interface
! 1470: ** to a custom page cache implementation.)^ ^SQLite makes a copy of the
! 1471: ** object and uses it for page cache memory allocations.</dd>
! 1472: **
! 1473: ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
! 1474: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1475: ** [sqlite3_pcache_methods2] object. SQLite copies of the current
! 1476: ** page cache implementation into that object.)^ </dd>
! 1477: **
! 1478: ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
! 1479: ** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
! 1480: ** function with a call signature of void(*)(void*,int,const char*),
! 1481: ** and a pointer to void. ^If the function pointer is not NULL, it is
! 1482: ** invoked by [sqlite3_log()] to process each logging event. ^If the
! 1483: ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
! 1484: ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
! 1485: ** passed through as the first parameter to the application-defined logger
! 1486: ** function whenever that function is invoked. ^The second parameter to
! 1487: ** the logger function is a copy of the first parameter to the corresponding
! 1488: ** [sqlite3_log()] call and is intended to be a [result code] or an
! 1489: ** [extended result code]. ^The third parameter passed to the logger is
! 1490: ** log message after formatting via [sqlite3_snprintf()].
! 1491: ** The SQLite logging interface is not reentrant; the logger function
! 1492: ** supplied by the application must not invoke any SQLite interface.
! 1493: ** In a multi-threaded application, the application-defined logger
! 1494: ** function must be threadsafe. </dd>
! 1495: **
! 1496: ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
! 1497: ** <dd> This option takes a single argument of type int. If non-zero, then
! 1498: ** URI handling is globally enabled. If the parameter is zero, then URI handling
! 1499: ** is globally disabled. If URI handling is globally enabled, all filenames
! 1500: ** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
! 1501: ** specified as part of [ATTACH] commands are interpreted as URIs, regardless
! 1502: ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
! 1503: ** connection is opened. If it is globally disabled, filenames are
! 1504: ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
! 1505: ** database connection is opened. By default, URI handling is globally
! 1506: ** disabled. The default value may be changed by compiling with the
! 1507: ** [SQLITE_USE_URI] symbol defined.
! 1508: **
! 1509: ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
! 1510: ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFNIG_GETPCACHE
! 1511: ** <dd> These options are obsolete and should not be used by new code.
! 1512: ** They are retained for backwards compatibility but are now no-ops.
! 1513: ** </dl>
! 1514: */
! 1515: #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
! 1516: #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
! 1517: #define SQLITE_CONFIG_SERIALIZED 3 /* nil */
! 1518: #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
! 1519: #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
! 1520: #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
! 1521: #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
! 1522: #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
! 1523: #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
! 1524: #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
! 1525: #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
! 1526: /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
! 1527: #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
! 1528: #define SQLITE_CONFIG_PCACHE 14 /* no-op */
! 1529: #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
! 1530: #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
! 1531: #define SQLITE_CONFIG_URI 17 /* int */
! 1532: #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
! 1533: #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
! 1534:
! 1535: /*
! 1536: ** CAPI3REF: Database Connection Configuration Options
! 1537: **
! 1538: ** These constants are the available integer configuration options that
! 1539: ** can be passed as the second argument to the [sqlite3_db_config()] interface.
! 1540: **
! 1541: ** New configuration options may be added in future releases of SQLite.
! 1542: ** Existing configuration options might be discontinued. Applications
! 1543: ** should check the return code from [sqlite3_db_config()] to make sure that
! 1544: ** the call worked. ^The [sqlite3_db_config()] interface will return a
! 1545: ** non-zero [error code] if a discontinued or unsupported configuration option
! 1546: ** is invoked.
! 1547: **
! 1548: ** <dl>
! 1549: ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
! 1550: ** <dd> ^This option takes three additional arguments that determine the
! 1551: ** [lookaside memory allocator] configuration for the [database connection].
! 1552: ** ^The first argument (the third parameter to [sqlite3_db_config()] is a
! 1553: ** pointer to a memory buffer to use for lookaside memory.
! 1554: ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
! 1555: ** may be NULL in which case SQLite will allocate the
! 1556: ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
! 1557: ** size of each lookaside buffer slot. ^The third argument is the number of
! 1558: ** slots. The size of the buffer in the first argument must be greater than
! 1559: ** or equal to the product of the second and third arguments. The buffer
! 1560: ** must be aligned to an 8-byte boundary. ^If the second argument to
! 1561: ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
! 1562: ** rounded down to the next smaller multiple of 8. ^(The lookaside memory
! 1563: ** configuration for a database connection can only be changed when that
! 1564: ** connection is not currently using lookaside memory, or in other words
! 1565: ** when the "current value" returned by
! 1566: ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
! 1567: ** Any attempt to change the lookaside memory configuration when lookaside
! 1568: ** memory is in use leaves the configuration unchanged and returns
! 1569: ** [SQLITE_BUSY].)^</dd>
! 1570: **
! 1571: ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
! 1572: ** <dd> ^This option is used to enable or disable the enforcement of
! 1573: ** [foreign key constraints]. There should be two additional arguments.
! 1574: ** The first argument is an integer which is 0 to disable FK enforcement,
! 1575: ** positive to enable FK enforcement or negative to leave FK enforcement
! 1576: ** unchanged. The second parameter is a pointer to an integer into which
! 1577: ** is written 0 or 1 to indicate whether FK enforcement is off or on
! 1578: ** following this call. The second parameter may be a NULL pointer, in
! 1579: ** which case the FK enforcement setting is not reported back. </dd>
! 1580: **
! 1581: ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
! 1582: ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
! 1583: ** There should be two additional arguments.
! 1584: ** The first argument is an integer which is 0 to disable triggers,
! 1585: ** positive to enable triggers or negative to leave the setting unchanged.
! 1586: ** The second parameter is a pointer to an integer into which
! 1587: ** is written 0 or 1 to indicate whether triggers are disabled or enabled
! 1588: ** following this call. The second parameter may be a NULL pointer, in
! 1589: ** which case the trigger setting is not reported back. </dd>
! 1590: **
! 1591: ** </dl>
! 1592: */
! 1593: #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
! 1594: #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
! 1595: #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
! 1596:
! 1597:
! 1598: /*
! 1599: ** CAPI3REF: Enable Or Disable Extended Result Codes
! 1600: **
! 1601: ** ^The sqlite3_extended_result_codes() routine enables or disables the
! 1602: ** [extended result codes] feature of SQLite. ^The extended result
! 1603: ** codes are disabled by default for historical compatibility.
! 1604: */
! 1605: int sqlite3_extended_result_codes(sqlite3*, int onoff);
! 1606:
! 1607: /*
! 1608: ** CAPI3REF: Last Insert Rowid
! 1609: **
! 1610: ** ^Each entry in an SQLite table has a unique 64-bit signed
! 1611: ** integer key called the [ROWID | "rowid"]. ^The rowid is always available
! 1612: ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
! 1613: ** names are not also used by explicitly declared columns. ^If
! 1614: ** the table has a column of type [INTEGER PRIMARY KEY] then that column
! 1615: ** is another alias for the rowid.
! 1616: **
! 1617: ** ^This routine returns the [rowid] of the most recent
! 1618: ** successful [INSERT] into the database from the [database connection]
! 1619: ** in the first argument. ^As of SQLite version 3.7.7, this routines
! 1620: ** records the last insert rowid of both ordinary tables and [virtual tables].
! 1621: ** ^If no successful [INSERT]s
! 1622: ** have ever occurred on that database connection, zero is returned.
! 1623: **
! 1624: ** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
! 1625: ** method, then this routine will return the [rowid] of the inserted
! 1626: ** row as long as the trigger or virtual table method is running.
! 1627: ** But once the trigger or virtual table method ends, the value returned
! 1628: ** by this routine reverts to what it was before the trigger or virtual
! 1629: ** table method began.)^
! 1630: **
! 1631: ** ^An [INSERT] that fails due to a constraint violation is not a
! 1632: ** successful [INSERT] and does not change the value returned by this
! 1633: ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
! 1634: ** and INSERT OR ABORT make no changes to the return value of this
! 1635: ** routine when their insertion fails. ^(When INSERT OR REPLACE
! 1636: ** encounters a constraint violation, it does not fail. The
! 1637: ** INSERT continues to completion after deleting rows that caused
! 1638: ** the constraint problem so INSERT OR REPLACE will always change
! 1639: ** the return value of this interface.)^
! 1640: **
! 1641: ** ^For the purposes of this routine, an [INSERT] is considered to
! 1642: ** be successful even if it is subsequently rolled back.
! 1643: **
! 1644: ** This function is accessible to SQL statements via the
! 1645: ** [last_insert_rowid() SQL function].
! 1646: **
! 1647: ** If a separate thread performs a new [INSERT] on the same
! 1648: ** database connection while the [sqlite3_last_insert_rowid()]
! 1649: ** function is running and thus changes the last insert [rowid],
! 1650: ** then the value returned by [sqlite3_last_insert_rowid()] is
! 1651: ** unpredictable and might not equal either the old or the new
! 1652: ** last insert [rowid].
! 1653: */
! 1654: sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
! 1655:
! 1656: /*
! 1657: ** CAPI3REF: Count The Number Of Rows Modified
! 1658: **
! 1659: ** ^This function returns the number of database rows that were changed
! 1660: ** or inserted or deleted by the most recently completed SQL statement
! 1661: ** on the [database connection] specified by the first parameter.
! 1662: ** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
! 1663: ** or [DELETE] statement are counted. Auxiliary changes caused by
! 1664: ** triggers or [foreign key actions] are not counted.)^ Use the
! 1665: ** [sqlite3_total_changes()] function to find the total number of changes
! 1666: ** including changes caused by triggers and foreign key actions.
! 1667: **
! 1668: ** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
! 1669: ** are not counted. Only real table changes are counted.
! 1670: **
! 1671: ** ^(A "row change" is a change to a single row of a single table
! 1672: ** caused by an INSERT, DELETE, or UPDATE statement. Rows that
! 1673: ** are changed as side effects of [REPLACE] constraint resolution,
! 1674: ** rollback, ABORT processing, [DROP TABLE], or by any other
! 1675: ** mechanisms do not count as direct row changes.)^
! 1676: **
! 1677: ** A "trigger context" is a scope of execution that begins and
! 1678: ** ends with the script of a [CREATE TRIGGER | trigger].
! 1679: ** Most SQL statements are
! 1680: ** evaluated outside of any trigger. This is the "top level"
! 1681: ** trigger context. If a trigger fires from the top level, a
! 1682: ** new trigger context is entered for the duration of that one
! 1683: ** trigger. Subtriggers create subcontexts for their duration.
! 1684: **
! 1685: ** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
! 1686: ** not create a new trigger context.
! 1687: **
! 1688: ** ^This function returns the number of direct row changes in the
! 1689: ** most recent INSERT, UPDATE, or DELETE statement within the same
! 1690: ** trigger context.
! 1691: **
! 1692: ** ^Thus, when called from the top level, this function returns the
! 1693: ** number of changes in the most recent INSERT, UPDATE, or DELETE
! 1694: ** that also occurred at the top level. ^(Within the body of a trigger,
! 1695: ** the sqlite3_changes() interface can be called to find the number of
! 1696: ** changes in the most recently completed INSERT, UPDATE, or DELETE
! 1697: ** statement within the body of the same trigger.
! 1698: ** However, the number returned does not include changes
! 1699: ** caused by subtriggers since those have their own context.)^
! 1700: **
! 1701: ** See also the [sqlite3_total_changes()] interface, the
! 1702: ** [count_changes pragma], and the [changes() SQL function].
! 1703: **
! 1704: ** If a separate thread makes changes on the same database connection
! 1705: ** while [sqlite3_changes()] is running then the value returned
! 1706: ** is unpredictable and not meaningful.
! 1707: */
! 1708: int sqlite3_changes(sqlite3*);
! 1709:
! 1710: /*
! 1711: ** CAPI3REF: Total Number Of Rows Modified
! 1712: **
! 1713: ** ^This function returns the number of row changes caused by [INSERT],
! 1714: ** [UPDATE] or [DELETE] statements since the [database connection] was opened.
! 1715: ** ^(The count returned by sqlite3_total_changes() includes all changes
! 1716: ** from all [CREATE TRIGGER | trigger] contexts and changes made by
! 1717: ** [foreign key actions]. However,
! 1718: ** the count does not include changes used to implement [REPLACE] constraints,
! 1719: ** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
! 1720: ** count does not include rows of views that fire an [INSTEAD OF trigger],
! 1721: ** though if the INSTEAD OF trigger makes changes of its own, those changes
! 1722: ** are counted.)^
! 1723: ** ^The sqlite3_total_changes() function counts the changes as soon as
! 1724: ** the statement that makes them is completed (when the statement handle
! 1725: ** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
! 1726: **
! 1727: ** See also the [sqlite3_changes()] interface, the
! 1728: ** [count_changes pragma], and the [total_changes() SQL function].
! 1729: **
! 1730: ** If a separate thread makes changes on the same database connection
! 1731: ** while [sqlite3_total_changes()] is running then the value
! 1732: ** returned is unpredictable and not meaningful.
! 1733: */
! 1734: int sqlite3_total_changes(sqlite3*);
! 1735:
! 1736: /*
! 1737: ** CAPI3REF: Interrupt A Long-Running Query
! 1738: **
! 1739: ** ^This function causes any pending database operation to abort and
! 1740: ** return at its earliest opportunity. This routine is typically
! 1741: ** called in response to a user action such as pressing "Cancel"
! 1742: ** or Ctrl-C where the user wants a long query operation to halt
! 1743: ** immediately.
! 1744: **
! 1745: ** ^It is safe to call this routine from a thread different from the
! 1746: ** thread that is currently running the database operation. But it
! 1747: ** is not safe to call this routine with a [database connection] that
! 1748: ** is closed or might close before sqlite3_interrupt() returns.
! 1749: **
! 1750: ** ^If an SQL operation is very nearly finished at the time when
! 1751: ** sqlite3_interrupt() is called, then it might not have an opportunity
! 1752: ** to be interrupted and might continue to completion.
! 1753: **
! 1754: ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
! 1755: ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
! 1756: ** that is inside an explicit transaction, then the entire transaction
! 1757: ** will be rolled back automatically.
! 1758: **
! 1759: ** ^The sqlite3_interrupt(D) call is in effect until all currently running
! 1760: ** SQL statements on [database connection] D complete. ^Any new SQL statements
! 1761: ** that are started after the sqlite3_interrupt() call and before the
! 1762: ** running statements reaches zero are interrupted as if they had been
! 1763: ** running prior to the sqlite3_interrupt() call. ^New SQL statements
! 1764: ** that are started after the running statement count reaches zero are
! 1765: ** not effected by the sqlite3_interrupt().
! 1766: ** ^A call to sqlite3_interrupt(D) that occurs when there are no running
! 1767: ** SQL statements is a no-op and has no effect on SQL statements
! 1768: ** that are started after the sqlite3_interrupt() call returns.
! 1769: **
! 1770: ** If the database connection closes while [sqlite3_interrupt()]
! 1771: ** is running then bad things will likely happen.
! 1772: */
! 1773: void sqlite3_interrupt(sqlite3*);
! 1774:
! 1775: /*
! 1776: ** CAPI3REF: Determine If An SQL Statement Is Complete
! 1777: **
! 1778: ** These routines are useful during command-line input to determine if the
! 1779: ** currently entered text seems to form a complete SQL statement or
! 1780: ** if additional input is needed before sending the text into
! 1781: ** SQLite for parsing. ^These routines return 1 if the input string
! 1782: ** appears to be a complete SQL statement. ^A statement is judged to be
! 1783: ** complete if it ends with a semicolon token and is not a prefix of a
! 1784: ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
! 1785: ** string literals or quoted identifier names or comments are not
! 1786: ** independent tokens (they are part of the token in which they are
! 1787: ** embedded) and thus do not count as a statement terminator. ^Whitespace
! 1788: ** and comments that follow the final semicolon are ignored.
! 1789: **
! 1790: ** ^These routines return 0 if the statement is incomplete. ^If a
! 1791: ** memory allocation fails, then SQLITE_NOMEM is returned.
! 1792: **
! 1793: ** ^These routines do not parse the SQL statements thus
! 1794: ** will not detect syntactically incorrect SQL.
! 1795: **
! 1796: ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
! 1797: ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
! 1798: ** automatically by sqlite3_complete16(). If that initialization fails,
! 1799: ** then the return value from sqlite3_complete16() will be non-zero
! 1800: ** regardless of whether or not the input SQL is complete.)^
! 1801: **
! 1802: ** The input to [sqlite3_complete()] must be a zero-terminated
! 1803: ** UTF-8 string.
! 1804: **
! 1805: ** The input to [sqlite3_complete16()] must be a zero-terminated
! 1806: ** UTF-16 string in native byte order.
! 1807: */
! 1808: int sqlite3_complete(const char *sql);
! 1809: int sqlite3_complete16(const void *sql);
! 1810:
! 1811: /*
! 1812: ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
! 1813: **
! 1814: ** ^This routine sets a callback function that might be invoked whenever
! 1815: ** an attempt is made to open a database table that another thread
! 1816: ** or process has locked.
! 1817: **
! 1818: ** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
! 1819: ** is returned immediately upon encountering the lock. ^If the busy callback
! 1820: ** is not NULL, then the callback might be invoked with two arguments.
! 1821: **
! 1822: ** ^The first argument to the busy handler is a copy of the void* pointer which
! 1823: ** is the third argument to sqlite3_busy_handler(). ^The second argument to
! 1824: ** the busy handler callback is the number of times that the busy handler has
! 1825: ** been invoked for this locking event. ^If the
! 1826: ** busy callback returns 0, then no additional attempts are made to
! 1827: ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
! 1828: ** ^If the callback returns non-zero, then another attempt
! 1829: ** is made to open the database for reading and the cycle repeats.
! 1830: **
! 1831: ** The presence of a busy handler does not guarantee that it will be invoked
! 1832: ** when there is lock contention. ^If SQLite determines that invoking the busy
! 1833: ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
! 1834: ** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
! 1835: ** Consider a scenario where one process is holding a read lock that
! 1836: ** it is trying to promote to a reserved lock and
! 1837: ** a second process is holding a reserved lock that it is trying
! 1838: ** to promote to an exclusive lock. The first process cannot proceed
! 1839: ** because it is blocked by the second and the second process cannot
! 1840: ** proceed because it is blocked by the first. If both processes
! 1841: ** invoke the busy handlers, neither will make any progress. Therefore,
! 1842: ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
! 1843: ** will induce the first process to release its read lock and allow
! 1844: ** the second process to proceed.
! 1845: **
! 1846: ** ^The default busy callback is NULL.
! 1847: **
! 1848: ** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
! 1849: ** when SQLite is in the middle of a large transaction where all the
! 1850: ** changes will not fit into the in-memory cache. SQLite will
! 1851: ** already hold a RESERVED lock on the database file, but it needs
! 1852: ** to promote this lock to EXCLUSIVE so that it can spill cache
! 1853: ** pages into the database file without harm to concurrent
! 1854: ** readers. ^If it is unable to promote the lock, then the in-memory
! 1855: ** cache will be left in an inconsistent state and so the error
! 1856: ** code is promoted from the relatively benign [SQLITE_BUSY] to
! 1857: ** the more severe [SQLITE_IOERR_BLOCKED]. ^This error code promotion
! 1858: ** forces an automatic rollback of the changes. See the
! 1859: ** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
! 1860: ** CorruptionFollowingBusyError</a> wiki page for a discussion of why
! 1861: ** this is important.
! 1862: **
! 1863: ** ^(There can only be a single busy handler defined for each
! 1864: ** [database connection]. Setting a new busy handler clears any
! 1865: ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
! 1866: ** will also set or clear the busy handler.
! 1867: **
! 1868: ** The busy callback should not take any actions which modify the
! 1869: ** database connection that invoked the busy handler. Any such actions
! 1870: ** result in undefined behavior.
! 1871: **
! 1872: ** A busy handler must not close the database connection
! 1873: ** or [prepared statement] that invoked the busy handler.
! 1874: */
! 1875: int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
! 1876:
! 1877: /*
! 1878: ** CAPI3REF: Set A Busy Timeout
! 1879: **
! 1880: ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
! 1881: ** for a specified amount of time when a table is locked. ^The handler
! 1882: ** will sleep multiple times until at least "ms" milliseconds of sleeping
! 1883: ** have accumulated. ^After at least "ms" milliseconds of sleeping,
! 1884: ** the handler returns 0 which causes [sqlite3_step()] to return
! 1885: ** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
! 1886: **
! 1887: ** ^Calling this routine with an argument less than or equal to zero
! 1888: ** turns off all busy handlers.
! 1889: **
! 1890: ** ^(There can only be a single busy handler for a particular
! 1891: ** [database connection] any any given moment. If another busy handler
! 1892: ** was defined (using [sqlite3_busy_handler()]) prior to calling
! 1893: ** this routine, that other busy handler is cleared.)^
! 1894: */
! 1895: int sqlite3_busy_timeout(sqlite3*, int ms);
! 1896:
! 1897: /*
! 1898: ** CAPI3REF: Convenience Routines For Running Queries
! 1899: **
! 1900: ** This is a legacy interface that is preserved for backwards compatibility.
! 1901: ** Use of this interface is not recommended.
! 1902: **
! 1903: ** Definition: A <b>result table</b> is memory data structure created by the
! 1904: ** [sqlite3_get_table()] interface. A result table records the
! 1905: ** complete query results from one or more queries.
! 1906: **
! 1907: ** The table conceptually has a number of rows and columns. But
! 1908: ** these numbers are not part of the result table itself. These
! 1909: ** numbers are obtained separately. Let N be the number of rows
! 1910: ** and M be the number of columns.
! 1911: **
! 1912: ** A result table is an array of pointers to zero-terminated UTF-8 strings.
! 1913: ** There are (N+1)*M elements in the array. The first M pointers point
! 1914: ** to zero-terminated strings that contain the names of the columns.
! 1915: ** The remaining entries all point to query results. NULL values result
! 1916: ** in NULL pointers. All other values are in their UTF-8 zero-terminated
! 1917: ** string representation as returned by [sqlite3_column_text()].
! 1918: **
! 1919: ** A result table might consist of one or more memory allocations.
! 1920: ** It is not safe to pass a result table directly to [sqlite3_free()].
! 1921: ** A result table should be deallocated using [sqlite3_free_table()].
! 1922: **
! 1923: ** ^(As an example of the result table format, suppose a query result
! 1924: ** is as follows:
! 1925: **
! 1926: ** <blockquote><pre>
! 1927: ** Name | Age
! 1928: ** -----------------------
! 1929: ** Alice | 43
! 1930: ** Bob | 28
! 1931: ** Cindy | 21
! 1932: ** </pre></blockquote>
! 1933: **
! 1934: ** There are two column (M==2) and three rows (N==3). Thus the
! 1935: ** result table has 8 entries. Suppose the result table is stored
! 1936: ** in an array names azResult. Then azResult holds this content:
! 1937: **
! 1938: ** <blockquote><pre>
! 1939: ** azResult[0] = "Name";
! 1940: ** azResult[1] = "Age";
! 1941: ** azResult[2] = "Alice";
! 1942: ** azResult[3] = "43";
! 1943: ** azResult[4] = "Bob";
! 1944: ** azResult[5] = "28";
! 1945: ** azResult[6] = "Cindy";
! 1946: ** azResult[7] = "21";
! 1947: ** </pre></blockquote>)^
! 1948: **
! 1949: ** ^The sqlite3_get_table() function evaluates one or more
! 1950: ** semicolon-separated SQL statements in the zero-terminated UTF-8
! 1951: ** string of its 2nd parameter and returns a result table to the
! 1952: ** pointer given in its 3rd parameter.
! 1953: **
! 1954: ** After the application has finished with the result from sqlite3_get_table(),
! 1955: ** it must pass the result table pointer to sqlite3_free_table() in order to
! 1956: ** release the memory that was malloced. Because of the way the
! 1957: ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
! 1958: ** function must not try to call [sqlite3_free()] directly. Only
! 1959: ** [sqlite3_free_table()] is able to release the memory properly and safely.
! 1960: **
! 1961: ** The sqlite3_get_table() interface is implemented as a wrapper around
! 1962: ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
! 1963: ** to any internal data structures of SQLite. It uses only the public
! 1964: ** interface defined here. As a consequence, errors that occur in the
! 1965: ** wrapper layer outside of the internal [sqlite3_exec()] call are not
! 1966: ** reflected in subsequent calls to [sqlite3_errcode()] or
! 1967: ** [sqlite3_errmsg()].
! 1968: */
! 1969: int sqlite3_get_table(
! 1970: sqlite3 *db, /* An open database */
! 1971: const char *zSql, /* SQL to be evaluated */
! 1972: char ***pazResult, /* Results of the query */
! 1973: int *pnRow, /* Number of result rows written here */
! 1974: int *pnColumn, /* Number of result columns written here */
! 1975: char **pzErrmsg /* Error msg written here */
! 1976: );
! 1977: void sqlite3_free_table(char **result);
! 1978:
! 1979: /*
! 1980: ** CAPI3REF: Formatted String Printing Functions
! 1981: **
! 1982: ** These routines are work-alikes of the "printf()" family of functions
! 1983: ** from the standard C library.
! 1984: **
! 1985: ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
! 1986: ** results into memory obtained from [sqlite3_malloc()].
! 1987: ** The strings returned by these two routines should be
! 1988: ** released by [sqlite3_free()]. ^Both routines return a
! 1989: ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
! 1990: ** memory to hold the resulting string.
! 1991: **
! 1992: ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
! 1993: ** the standard C library. The result is written into the
! 1994: ** buffer supplied as the second parameter whose size is given by
! 1995: ** the first parameter. Note that the order of the
! 1996: ** first two parameters is reversed from snprintf().)^ This is an
! 1997: ** historical accident that cannot be fixed without breaking
! 1998: ** backwards compatibility. ^(Note also that sqlite3_snprintf()
! 1999: ** returns a pointer to its buffer instead of the number of
! 2000: ** characters actually written into the buffer.)^ We admit that
! 2001: ** the number of characters written would be a more useful return
! 2002: ** value but we cannot change the implementation of sqlite3_snprintf()
! 2003: ** now without breaking compatibility.
! 2004: **
! 2005: ** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
! 2006: ** guarantees that the buffer is always zero-terminated. ^The first
! 2007: ** parameter "n" is the total size of the buffer, including space for
! 2008: ** the zero terminator. So the longest string that can be completely
! 2009: ** written will be n-1 characters.
! 2010: **
! 2011: ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
! 2012: **
! 2013: ** These routines all implement some additional formatting
! 2014: ** options that are useful for constructing SQL statements.
! 2015: ** All of the usual printf() formatting options apply. In addition, there
! 2016: ** is are "%q", "%Q", and "%z" options.
! 2017: **
! 2018: ** ^(The %q option works like %s in that it substitutes a nul-terminated
! 2019: ** string from the argument list. But %q also doubles every '\'' character.
! 2020: ** %q is designed for use inside a string literal.)^ By doubling each '\''
! 2021: ** character it escapes that character and allows it to be inserted into
! 2022: ** the string.
! 2023: **
! 2024: ** For example, assume the string variable zText contains text as follows:
! 2025: **
! 2026: ** <blockquote><pre>
! 2027: ** char *zText = "It's a happy day!";
! 2028: ** </pre></blockquote>
! 2029: **
! 2030: ** One can use this text in an SQL statement as follows:
! 2031: **
! 2032: ** <blockquote><pre>
! 2033: ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
! 2034: ** sqlite3_exec(db, zSQL, 0, 0, 0);
! 2035: ** sqlite3_free(zSQL);
! 2036: ** </pre></blockquote>
! 2037: **
! 2038: ** Because the %q format string is used, the '\'' character in zText
! 2039: ** is escaped and the SQL generated is as follows:
! 2040: **
! 2041: ** <blockquote><pre>
! 2042: ** INSERT INTO table1 VALUES('It''s a happy day!')
! 2043: ** </pre></blockquote>
! 2044: **
! 2045: ** This is correct. Had we used %s instead of %q, the generated SQL
! 2046: ** would have looked like this:
! 2047: **
! 2048: ** <blockquote><pre>
! 2049: ** INSERT INTO table1 VALUES('It's a happy day!');
! 2050: ** </pre></blockquote>
! 2051: **
! 2052: ** This second example is an SQL syntax error. As a general rule you should
! 2053: ** always use %q instead of %s when inserting text into a string literal.
! 2054: **
! 2055: ** ^(The %Q option works like %q except it also adds single quotes around
! 2056: ** the outside of the total string. Additionally, if the parameter in the
! 2057: ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
! 2058: ** single quotes).)^ So, for example, one could say:
! 2059: **
! 2060: ** <blockquote><pre>
! 2061: ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
! 2062: ** sqlite3_exec(db, zSQL, 0, 0, 0);
! 2063: ** sqlite3_free(zSQL);
! 2064: ** </pre></blockquote>
! 2065: **
! 2066: ** The code above will render a correct SQL statement in the zSQL
! 2067: ** variable even if the zText variable is a NULL pointer.
! 2068: **
! 2069: ** ^(The "%z" formatting option works like "%s" but with the
! 2070: ** addition that after the string has been read and copied into
! 2071: ** the result, [sqlite3_free()] is called on the input string.)^
! 2072: */
! 2073: char *sqlite3_mprintf(const char*,...);
! 2074: char *sqlite3_vmprintf(const char*, va_list);
! 2075: char *sqlite3_snprintf(int,char*,const char*, ...);
! 2076: char *sqlite3_vsnprintf(int,char*,const char*, va_list);
! 2077:
! 2078: /*
! 2079: ** CAPI3REF: Memory Allocation Subsystem
! 2080: **
! 2081: ** The SQLite core uses these three routines for all of its own
! 2082: ** internal memory allocation needs. "Core" in the previous sentence
! 2083: ** does not include operating-system specific VFS implementation. The
! 2084: ** Windows VFS uses native malloc() and free() for some operations.
! 2085: **
! 2086: ** ^The sqlite3_malloc() routine returns a pointer to a block
! 2087: ** of memory at least N bytes in length, where N is the parameter.
! 2088: ** ^If sqlite3_malloc() is unable to obtain sufficient free
! 2089: ** memory, it returns a NULL pointer. ^If the parameter N to
! 2090: ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
! 2091: ** a NULL pointer.
! 2092: **
! 2093: ** ^Calling sqlite3_free() with a pointer previously returned
! 2094: ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
! 2095: ** that it might be reused. ^The sqlite3_free() routine is
! 2096: ** a no-op if is called with a NULL pointer. Passing a NULL pointer
! 2097: ** to sqlite3_free() is harmless. After being freed, memory
! 2098: ** should neither be read nor written. Even reading previously freed
! 2099: ** memory might result in a segmentation fault or other severe error.
! 2100: ** Memory corruption, a segmentation fault, or other severe error
! 2101: ** might result if sqlite3_free() is called with a non-NULL pointer that
! 2102: ** was not obtained from sqlite3_malloc() or sqlite3_realloc().
! 2103: **
! 2104: ** ^(The sqlite3_realloc() interface attempts to resize a
! 2105: ** prior memory allocation to be at least N bytes, where N is the
! 2106: ** second parameter. The memory allocation to be resized is the first
! 2107: ** parameter.)^ ^ If the first parameter to sqlite3_realloc()
! 2108: ** is a NULL pointer then its behavior is identical to calling
! 2109: ** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
! 2110: ** ^If the second parameter to sqlite3_realloc() is zero or
! 2111: ** negative then the behavior is exactly the same as calling
! 2112: ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
! 2113: ** ^sqlite3_realloc() returns a pointer to a memory allocation
! 2114: ** of at least N bytes in size or NULL if sufficient memory is unavailable.
! 2115: ** ^If M is the size of the prior allocation, then min(N,M) bytes
! 2116: ** of the prior allocation are copied into the beginning of buffer returned
! 2117: ** by sqlite3_realloc() and the prior allocation is freed.
! 2118: ** ^If sqlite3_realloc() returns NULL, then the prior allocation
! 2119: ** is not freed.
! 2120: **
! 2121: ** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
! 2122: ** is always aligned to at least an 8 byte boundary, or to a
! 2123: ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
! 2124: ** option is used.
! 2125: **
! 2126: ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
! 2127: ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
! 2128: ** implementation of these routines to be omitted. That capability
! 2129: ** is no longer provided. Only built-in memory allocators can be used.
! 2130: **
! 2131: ** The Windows OS interface layer calls
! 2132: ** the system malloc() and free() directly when converting
! 2133: ** filenames between the UTF-8 encoding used by SQLite
! 2134: ** and whatever filename encoding is used by the particular Windows
! 2135: ** installation. Memory allocation errors are detected, but
! 2136: ** they are reported back as [SQLITE_CANTOPEN] or
! 2137: ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
! 2138: **
! 2139: ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
! 2140: ** must be either NULL or else pointers obtained from a prior
! 2141: ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
! 2142: ** not yet been released.
! 2143: **
! 2144: ** The application must not read or write any part of
! 2145: ** a block of memory after it has been released using
! 2146: ** [sqlite3_free()] or [sqlite3_realloc()].
! 2147: */
! 2148: void *sqlite3_malloc(int);
! 2149: void *sqlite3_realloc(void*, int);
! 2150: void sqlite3_free(void*);
! 2151:
! 2152: /*
! 2153: ** CAPI3REF: Memory Allocator Statistics
! 2154: **
! 2155: ** SQLite provides these two interfaces for reporting on the status
! 2156: ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
! 2157: ** routines, which form the built-in memory allocation subsystem.
! 2158: **
! 2159: ** ^The [sqlite3_memory_used()] routine returns the number of bytes
! 2160: ** of memory currently outstanding (malloced but not freed).
! 2161: ** ^The [sqlite3_memory_highwater()] routine returns the maximum
! 2162: ** value of [sqlite3_memory_used()] since the high-water mark
! 2163: ** was last reset. ^The values returned by [sqlite3_memory_used()] and
! 2164: ** [sqlite3_memory_highwater()] include any overhead
! 2165: ** added by SQLite in its implementation of [sqlite3_malloc()],
! 2166: ** but not overhead added by the any underlying system library
! 2167: ** routines that [sqlite3_malloc()] may call.
! 2168: **
! 2169: ** ^The memory high-water mark is reset to the current value of
! 2170: ** [sqlite3_memory_used()] if and only if the parameter to
! 2171: ** [sqlite3_memory_highwater()] is true. ^The value returned
! 2172: ** by [sqlite3_memory_highwater(1)] is the high-water mark
! 2173: ** prior to the reset.
! 2174: */
! 2175: sqlite3_int64 sqlite3_memory_used(void);
! 2176: sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
! 2177:
! 2178: /*
! 2179: ** CAPI3REF: Pseudo-Random Number Generator
! 2180: **
! 2181: ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
! 2182: ** select random [ROWID | ROWIDs] when inserting new records into a table that
! 2183: ** already uses the largest possible [ROWID]. The PRNG is also used for
! 2184: ** the build-in random() and randomblob() SQL functions. This interface allows
! 2185: ** applications to access the same PRNG for other purposes.
! 2186: **
! 2187: ** ^A call to this routine stores N bytes of randomness into buffer P.
! 2188: **
! 2189: ** ^The first time this routine is invoked (either internally or by
! 2190: ** the application) the PRNG is seeded using randomness obtained
! 2191: ** from the xRandomness method of the default [sqlite3_vfs] object.
! 2192: ** ^On all subsequent invocations, the pseudo-randomness is generated
! 2193: ** internally and without recourse to the [sqlite3_vfs] xRandomness
! 2194: ** method.
! 2195: */
! 2196: void sqlite3_randomness(int N, void *P);
! 2197:
! 2198: /*
! 2199: ** CAPI3REF: Compile-Time Authorization Callbacks
! 2200: **
! 2201: ** ^This routine registers an authorizer callback with a particular
! 2202: ** [database connection], supplied in the first argument.
! 2203: ** ^The authorizer callback is invoked as SQL statements are being compiled
! 2204: ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
! 2205: ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
! 2206: ** points during the compilation process, as logic is being created
! 2207: ** to perform various actions, the authorizer callback is invoked to
! 2208: ** see if those actions are allowed. ^The authorizer callback should
! 2209: ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
! 2210: ** specific action but allow the SQL statement to continue to be
! 2211: ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
! 2212: ** rejected with an error. ^If the authorizer callback returns
! 2213: ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
! 2214: ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
! 2215: ** the authorizer will fail with an error message.
! 2216: **
! 2217: ** When the callback returns [SQLITE_OK], that means the operation
! 2218: ** requested is ok. ^When the callback returns [SQLITE_DENY], the
! 2219: ** [sqlite3_prepare_v2()] or equivalent call that triggered the
! 2220: ** authorizer will fail with an error message explaining that
! 2221: ** access is denied.
! 2222: **
! 2223: ** ^The first parameter to the authorizer callback is a copy of the third
! 2224: ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
! 2225: ** to the callback is an integer [SQLITE_COPY | action code] that specifies
! 2226: ** the particular action to be authorized. ^The third through sixth parameters
! 2227: ** to the callback are zero-terminated strings that contain additional
! 2228: ** details about the action to be authorized.
! 2229: **
! 2230: ** ^If the action code is [SQLITE_READ]
! 2231: ** and the callback returns [SQLITE_IGNORE] then the
! 2232: ** [prepared statement] statement is constructed to substitute
! 2233: ** a NULL value in place of the table column that would have
! 2234: ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
! 2235: ** return can be used to deny an untrusted user access to individual
! 2236: ** columns of a table.
! 2237: ** ^If the action code is [SQLITE_DELETE] and the callback returns
! 2238: ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
! 2239: ** [truncate optimization] is disabled and all rows are deleted individually.
! 2240: **
! 2241: ** An authorizer is used when [sqlite3_prepare | preparing]
! 2242: ** SQL statements from an untrusted source, to ensure that the SQL statements
! 2243: ** do not try to access data they are not allowed to see, or that they do not
! 2244: ** try to execute malicious statements that damage the database. For
! 2245: ** example, an application may allow a user to enter arbitrary
! 2246: ** SQL queries for evaluation by a database. But the application does
! 2247: ** not want the user to be able to make arbitrary changes to the
! 2248: ** database. An authorizer could then be put in place while the
! 2249: ** user-entered SQL is being [sqlite3_prepare | prepared] that
! 2250: ** disallows everything except [SELECT] statements.
! 2251: **
! 2252: ** Applications that need to process SQL from untrusted sources
! 2253: ** might also consider lowering resource limits using [sqlite3_limit()]
! 2254: ** and limiting database size using the [max_page_count] [PRAGMA]
! 2255: ** in addition to using an authorizer.
! 2256: **
! 2257: ** ^(Only a single authorizer can be in place on a database connection
! 2258: ** at a time. Each call to sqlite3_set_authorizer overrides the
! 2259: ** previous call.)^ ^Disable the authorizer by installing a NULL callback.
! 2260: ** The authorizer is disabled by default.
! 2261: **
! 2262: ** The authorizer callback must not do anything that will modify
! 2263: ** the database connection that invoked the authorizer callback.
! 2264: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
! 2265: ** database connections for the meaning of "modify" in this paragraph.
! 2266: **
! 2267: ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
! 2268: ** statement might be re-prepared during [sqlite3_step()] due to a
! 2269: ** schema change. Hence, the application should ensure that the
! 2270: ** correct authorizer callback remains in place during the [sqlite3_step()].
! 2271: **
! 2272: ** ^Note that the authorizer callback is invoked only during
! 2273: ** [sqlite3_prepare()] or its variants. Authorization is not
! 2274: ** performed during statement evaluation in [sqlite3_step()], unless
! 2275: ** as stated in the previous paragraph, sqlite3_step() invokes
! 2276: ** sqlite3_prepare_v2() to reprepare a statement after a schema change.
! 2277: */
! 2278: int sqlite3_set_authorizer(
! 2279: sqlite3*,
! 2280: int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
! 2281: void *pUserData
! 2282: );
! 2283:
! 2284: /*
! 2285: ** CAPI3REF: Authorizer Return Codes
! 2286: **
! 2287: ** The [sqlite3_set_authorizer | authorizer callback function] must
! 2288: ** return either [SQLITE_OK] or one of these two constants in order
! 2289: ** to signal SQLite whether or not the action is permitted. See the
! 2290: ** [sqlite3_set_authorizer | authorizer documentation] for additional
! 2291: ** information.
! 2292: **
! 2293: ** Note that SQLITE_IGNORE is also used as a [SQLITE_ROLLBACK | return code]
! 2294: ** from the [sqlite3_vtab_on_conflict()] interface.
! 2295: */
! 2296: #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
! 2297: #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
! 2298:
! 2299: /*
! 2300: ** CAPI3REF: Authorizer Action Codes
! 2301: **
! 2302: ** The [sqlite3_set_authorizer()] interface registers a callback function
! 2303: ** that is invoked to authorize certain SQL statement actions. The
! 2304: ** second parameter to the callback is an integer code that specifies
! 2305: ** what action is being authorized. These are the integer action codes that
! 2306: ** the authorizer callback may be passed.
! 2307: **
! 2308: ** These action code values signify what kind of operation is to be
! 2309: ** authorized. The 3rd and 4th parameters to the authorization
! 2310: ** callback function will be parameters or NULL depending on which of these
! 2311: ** codes is used as the second parameter. ^(The 5th parameter to the
! 2312: ** authorizer callback is the name of the database ("main", "temp",
! 2313: ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
! 2314: ** is the name of the inner-most trigger or view that is responsible for
! 2315: ** the access attempt or NULL if this access attempt is directly from
! 2316: ** top-level SQL code.
! 2317: */
! 2318: /******************************************* 3rd ************ 4th ***********/
! 2319: #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
! 2320: #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
! 2321: #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
! 2322: #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
! 2323: #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
! 2324: #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
! 2325: #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
! 2326: #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
! 2327: #define SQLITE_DELETE 9 /* Table Name NULL */
! 2328: #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
! 2329: #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
! 2330: #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
! 2331: #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
! 2332: #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
! 2333: #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
! 2334: #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
! 2335: #define SQLITE_DROP_VIEW 17 /* View Name NULL */
! 2336: #define SQLITE_INSERT 18 /* Table Name NULL */
! 2337: #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
! 2338: #define SQLITE_READ 20 /* Table Name Column Name */
! 2339: #define SQLITE_SELECT 21 /* NULL NULL */
! 2340: #define SQLITE_TRANSACTION 22 /* Operation NULL */
! 2341: #define SQLITE_UPDATE 23 /* Table Name Column Name */
! 2342: #define SQLITE_ATTACH 24 /* Filename NULL */
! 2343: #define SQLITE_DETACH 25 /* Database Name NULL */
! 2344: #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
! 2345: #define SQLITE_REINDEX 27 /* Index Name NULL */
! 2346: #define SQLITE_ANALYZE 28 /* Table Name NULL */
! 2347: #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
! 2348: #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
! 2349: #define SQLITE_FUNCTION 31 /* NULL Function Name */
! 2350: #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
! 2351: #define SQLITE_COPY 0 /* No longer used */
! 2352:
! 2353: /*
! 2354: ** CAPI3REF: Tracing And Profiling Functions
! 2355: **
! 2356: ** These routines register callback functions that can be used for
! 2357: ** tracing and profiling the execution of SQL statements.
! 2358: **
! 2359: ** ^The callback function registered by sqlite3_trace() is invoked at
! 2360: ** various times when an SQL statement is being run by [sqlite3_step()].
! 2361: ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
! 2362: ** SQL statement text as the statement first begins executing.
! 2363: ** ^(Additional sqlite3_trace() callbacks might occur
! 2364: ** as each triggered subprogram is entered. The callbacks for triggers
! 2365: ** contain a UTF-8 SQL comment that identifies the trigger.)^
! 2366: **
! 2367: ** ^The callback function registered by sqlite3_profile() is invoked
! 2368: ** as each SQL statement finishes. ^The profile callback contains
! 2369: ** the original statement text and an estimate of wall-clock time
! 2370: ** of how long that statement took to run. ^The profile callback
! 2371: ** time is in units of nanoseconds, however the current implementation
! 2372: ** is only capable of millisecond resolution so the six least significant
! 2373: ** digits in the time are meaningless. Future versions of SQLite
! 2374: ** might provide greater resolution on the profiler callback. The
! 2375: ** sqlite3_profile() function is considered experimental and is
! 2376: ** subject to change in future versions of SQLite.
! 2377: */
! 2378: void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
! 2379: SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
! 2380: void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
! 2381:
! 2382: /*
! 2383: ** CAPI3REF: Query Progress Callbacks
! 2384: **
! 2385: ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
! 2386: ** function X to be invoked periodically during long running calls to
! 2387: ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
! 2388: ** database connection D. An example use for this
! 2389: ** interface is to keep a GUI updated during a large query.
! 2390: **
! 2391: ** ^The parameter P is passed through as the only parameter to the
! 2392: ** callback function X. ^The parameter N is the number of
! 2393: ** [virtual machine instructions] that are evaluated between successive
! 2394: ** invocations of the callback X.
! 2395: **
! 2396: ** ^Only a single progress handler may be defined at one time per
! 2397: ** [database connection]; setting a new progress handler cancels the
! 2398: ** old one. ^Setting parameter X to NULL disables the progress handler.
! 2399: ** ^The progress handler is also disabled by setting N to a value less
! 2400: ** than 1.
! 2401: **
! 2402: ** ^If the progress callback returns non-zero, the operation is
! 2403: ** interrupted. This feature can be used to implement a
! 2404: ** "Cancel" button on a GUI progress dialog box.
! 2405: **
! 2406: ** The progress handler callback must not do anything that will modify
! 2407: ** the database connection that invoked the progress handler.
! 2408: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
! 2409: ** database connections for the meaning of "modify" in this paragraph.
! 2410: **
! 2411: */
! 2412: void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
! 2413:
! 2414: /*
! 2415: ** CAPI3REF: Opening A New Database Connection
! 2416: **
! 2417: ** ^These routines open an SQLite database file as specified by the
! 2418: ** filename argument. ^The filename argument is interpreted as UTF-8 for
! 2419: ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
! 2420: ** order for sqlite3_open16(). ^(A [database connection] handle is usually
! 2421: ** returned in *ppDb, even if an error occurs. The only exception is that
! 2422: ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
! 2423: ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
! 2424: ** object.)^ ^(If the database is opened (and/or created) successfully, then
! 2425: ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
! 2426: ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
! 2427: ** an English language description of the error following a failure of any
! 2428: ** of the sqlite3_open() routines.
! 2429: **
! 2430: ** ^The default encoding for the database will be UTF-8 if
! 2431: ** sqlite3_open() or sqlite3_open_v2() is called and
! 2432: ** UTF-16 in the native byte order if sqlite3_open16() is used.
! 2433: **
! 2434: ** Whether or not an error occurs when it is opened, resources
! 2435: ** associated with the [database connection] handle should be released by
! 2436: ** passing it to [sqlite3_close()] when it is no longer required.
! 2437: **
! 2438: ** The sqlite3_open_v2() interface works like sqlite3_open()
! 2439: ** except that it accepts two additional parameters for additional control
! 2440: ** over the new database connection. ^(The flags parameter to
! 2441: ** sqlite3_open_v2() can take one of
! 2442: ** the following three values, optionally combined with the
! 2443: ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
! 2444: ** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
! 2445: **
! 2446: ** <dl>
! 2447: ** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
! 2448: ** <dd>The database is opened in read-only mode. If the database does not
! 2449: ** already exist, an error is returned.</dd>)^
! 2450: **
! 2451: ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
! 2452: ** <dd>The database is opened for reading and writing if possible, or reading
! 2453: ** only if the file is write protected by the operating system. In either
! 2454: ** case the database must already exist, otherwise an error is returned.</dd>)^
! 2455: **
! 2456: ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
! 2457: ** <dd>The database is opened for reading and writing, and is created if
! 2458: ** it does not already exist. This is the behavior that is always used for
! 2459: ** sqlite3_open() and sqlite3_open16().</dd>)^
! 2460: ** </dl>
! 2461: **
! 2462: ** If the 3rd parameter to sqlite3_open_v2() is not one of the
! 2463: ** combinations shown above optionally combined with other
! 2464: ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
! 2465: ** then the behavior is undefined.
! 2466: **
! 2467: ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
! 2468: ** opens in the multi-thread [threading mode] as long as the single-thread
! 2469: ** mode has not been set at compile-time or start-time. ^If the
! 2470: ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
! 2471: ** in the serialized [threading mode] unless single-thread was
! 2472: ** previously selected at compile-time or start-time.
! 2473: ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
! 2474: ** eligible to use [shared cache mode], regardless of whether or not shared
! 2475: ** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
! 2476: ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
! 2477: ** participate in [shared cache mode] even if it is enabled.
! 2478: **
! 2479: ** ^The fourth parameter to sqlite3_open_v2() is the name of the
! 2480: ** [sqlite3_vfs] object that defines the operating system interface that
! 2481: ** the new database connection should use. ^If the fourth parameter is
! 2482: ** a NULL pointer then the default [sqlite3_vfs] object is used.
! 2483: **
! 2484: ** ^If the filename is ":memory:", then a private, temporary in-memory database
! 2485: ** is created for the connection. ^This in-memory database will vanish when
! 2486: ** the database connection is closed. Future versions of SQLite might
! 2487: ** make use of additional special filenames that begin with the ":" character.
! 2488: ** It is recommended that when a database filename actually does begin with
! 2489: ** a ":" character you should prefix the filename with a pathname such as
! 2490: ** "./" to avoid ambiguity.
! 2491: **
! 2492: ** ^If the filename is an empty string, then a private, temporary
! 2493: ** on-disk database will be created. ^This private database will be
! 2494: ** automatically deleted as soon as the database connection is closed.
! 2495: **
! 2496: ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
! 2497: **
! 2498: ** ^If [URI filename] interpretation is enabled, and the filename argument
! 2499: ** begins with "file:", then the filename is interpreted as a URI. ^URI
! 2500: ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
! 2501: ** set in the fourth argument to sqlite3_open_v2(), or if it has
! 2502: ** been enabled globally using the [SQLITE_CONFIG_URI] option with the
! 2503: ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
! 2504: ** As of SQLite version 3.7.7, URI filename interpretation is turned off
! 2505: ** by default, but future releases of SQLite might enable URI filename
! 2506: ** interpretation by default. See "[URI filenames]" for additional
! 2507: ** information.
! 2508: **
! 2509: ** URI filenames are parsed according to RFC 3986. ^If the URI contains an
! 2510: ** authority, then it must be either an empty string or the string
! 2511: ** "localhost". ^If the authority is not an empty string or "localhost", an
! 2512: ** error is returned to the caller. ^The fragment component of a URI, if
! 2513: ** present, is ignored.
! 2514: **
! 2515: ** ^SQLite uses the path component of the URI as the name of the disk file
! 2516: ** which contains the database. ^If the path begins with a '/' character,
! 2517: ** then it is interpreted as an absolute path. ^If the path does not begin
! 2518: ** with a '/' (meaning that the authority section is omitted from the URI)
! 2519: ** then the path is interpreted as a relative path.
! 2520: ** ^On windows, the first component of an absolute path
! 2521: ** is a drive specification (e.g. "C:").
! 2522: **
! 2523: ** [[core URI query parameters]]
! 2524: ** The query component of a URI may contain parameters that are interpreted
! 2525: ** either by SQLite itself, or by a [VFS | custom VFS implementation].
! 2526: ** SQLite interprets the following three query parameters:
! 2527: **
! 2528: ** <ul>
! 2529: ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
! 2530: ** a VFS object that provides the operating system interface that should
! 2531: ** be used to access the database file on disk. ^If this option is set to
! 2532: ** an empty string the default VFS object is used. ^Specifying an unknown
! 2533: ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
! 2534: ** present, then the VFS specified by the option takes precedence over
! 2535: ** the value passed as the fourth parameter to sqlite3_open_v2().
! 2536: **
! 2537: ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw" or
! 2538: ** "rwc". Attempting to set it to any other value is an error)^.
! 2539: ** ^If "ro" is specified, then the database is opened for read-only
! 2540: ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
! 2541: ** third argument to sqlite3_prepare_v2(). ^If the mode option is set to
! 2542: ** "rw", then the database is opened for read-write (but not create)
! 2543: ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
! 2544: ** been set. ^Value "rwc" is equivalent to setting both
! 2545: ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If sqlite3_open_v2() is
! 2546: ** used, it is an error to specify a value for the mode parameter that is
! 2547: ** less restrictive than that specified by the flags passed as the third
! 2548: ** parameter.
! 2549: **
! 2550: ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
! 2551: ** "private". ^Setting it to "shared" is equivalent to setting the
! 2552: ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
! 2553: ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
! 2554: ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
! 2555: ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
! 2556: ** a URI filename, its value overrides any behaviour requested by setting
! 2557: ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
! 2558: ** </ul>
! 2559: **
! 2560: ** ^Specifying an unknown parameter in the query component of a URI is not an
! 2561: ** error. Future versions of SQLite might understand additional query
! 2562: ** parameters. See "[query parameters with special meaning to SQLite]" for
! 2563: ** additional information.
! 2564: **
! 2565: ** [[URI filename examples]] <h3>URI filename examples</h3>
! 2566: **
! 2567: ** <table border="1" align=center cellpadding=5>
! 2568: ** <tr><th> URI filenames <th> Results
! 2569: ** <tr><td> file:data.db <td>
! 2570: ** Open the file "data.db" in the current directory.
! 2571: ** <tr><td> file:/home/fred/data.db<br>
! 2572: ** file:///home/fred/data.db <br>
! 2573: ** file://localhost/home/fred/data.db <br> <td>
! 2574: ** Open the database file "/home/fred/data.db".
! 2575: ** <tr><td> file://darkstar/home/fred/data.db <td>
! 2576: ** An error. "darkstar" is not a recognized authority.
! 2577: ** <tr><td style="white-space:nowrap">
! 2578: ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
! 2579: ** <td> Windows only: Open the file "data.db" on fred's desktop on drive
! 2580: ** C:. Note that the %20 escaping in this example is not strictly
! 2581: ** necessary - space characters can be used literally
! 2582: ** in URI filenames.
! 2583: ** <tr><td> file:data.db?mode=ro&cache=private <td>
! 2584: ** Open file "data.db" in the current directory for read-only access.
! 2585: ** Regardless of whether or not shared-cache mode is enabled by
! 2586: ** default, use a private cache.
! 2587: ** <tr><td> file:/home/fred/data.db?vfs=unix-nolock <td>
! 2588: ** Open file "/home/fred/data.db". Use the special VFS "unix-nolock".
! 2589: ** <tr><td> file:data.db?mode=readonly <td>
! 2590: ** An error. "readonly" is not a valid option for the "mode" parameter.
! 2591: ** </table>
! 2592: **
! 2593: ** ^URI hexadecimal escape sequences (%HH) are supported within the path and
! 2594: ** query components of a URI. A hexadecimal escape sequence consists of a
! 2595: ** percent sign - "%" - followed by exactly two hexadecimal digits
! 2596: ** specifying an octet value. ^Before the path or query components of a
! 2597: ** URI filename are interpreted, they are encoded using UTF-8 and all
! 2598: ** hexadecimal escape sequences replaced by a single byte containing the
! 2599: ** corresponding octet. If this process generates an invalid UTF-8 encoding,
! 2600: ** the results are undefined.
! 2601: **
! 2602: ** <b>Note to Windows users:</b> The encoding used for the filename argument
! 2603: ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
! 2604: ** codepage is currently defined. Filenames containing international
! 2605: ** characters must be converted to UTF-8 prior to passing them into
! 2606: ** sqlite3_open() or sqlite3_open_v2().
! 2607: */
! 2608: int sqlite3_open(
! 2609: const char *filename, /* Database filename (UTF-8) */
! 2610: sqlite3 **ppDb /* OUT: SQLite db handle */
! 2611: );
! 2612: int sqlite3_open16(
! 2613: const void *filename, /* Database filename (UTF-16) */
! 2614: sqlite3 **ppDb /* OUT: SQLite db handle */
! 2615: );
! 2616: int sqlite3_open_v2(
! 2617: const char *filename, /* Database filename (UTF-8) */
! 2618: sqlite3 **ppDb, /* OUT: SQLite db handle */
! 2619: int flags, /* Flags */
! 2620: const char *zVfs /* Name of VFS module to use */
! 2621: );
! 2622:
! 2623: /*
! 2624: ** CAPI3REF: Obtain Values For URI Parameters
! 2625: **
! 2626: ** These are utility routines, useful to VFS implementations, that check
! 2627: ** to see if a database file was a URI that contained a specific query
! 2628: ** parameter, and if so obtains the value of that query parameter.
! 2629: **
! 2630: ** If F is the database filename pointer passed into the xOpen() method of
! 2631: ** a VFS implementation when the flags parameter to xOpen() has one or
! 2632: ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
! 2633: ** P is the name of the query parameter, then
! 2634: ** sqlite3_uri_parameter(F,P) returns the value of the P
! 2635: ** parameter if it exists or a NULL pointer if P does not appear as a
! 2636: ** query parameter on F. If P is a query parameter of F
! 2637: ** has no explicit value, then sqlite3_uri_parameter(F,P) returns
! 2638: ** a pointer to an empty string.
! 2639: **
! 2640: ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
! 2641: ** parameter and returns true (1) or false (0) according to the value
! 2642: ** of P. The value of P is true if it is "yes" or "true" or "on" or
! 2643: ** a non-zero number and is false otherwise. If P is not a query parameter
! 2644: ** on F then sqlite3_uri_boolean(F,P,B) returns (B!=0).
! 2645: **
! 2646: ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
! 2647: ** 64-bit signed integer and returns that integer, or D if P does not
! 2648: ** exist. If the value of P is something other than an integer, then
! 2649: ** zero is returned.
! 2650: **
! 2651: ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
! 2652: ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
! 2653: ** is not a database file pathname pointer that SQLite passed into the xOpen
! 2654: ** VFS method, then the behavior of this routine is undefined and probably
! 2655: ** undesirable.
! 2656: */
! 2657: const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
! 2658: int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
! 2659: sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
! 2660:
! 2661:
! 2662: /*
! 2663: ** CAPI3REF: Error Codes And Messages
! 2664: **
! 2665: ** ^The sqlite3_errcode() interface returns the numeric [result code] or
! 2666: ** [extended result code] for the most recent failed sqlite3_* API call
! 2667: ** associated with a [database connection]. If a prior API call failed
! 2668: ** but the most recent API call succeeded, the return value from
! 2669: ** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode()
! 2670: ** interface is the same except that it always returns the
! 2671: ** [extended result code] even when extended result codes are
! 2672: ** disabled.
! 2673: **
! 2674: ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
! 2675: ** text that describes the error, as either UTF-8 or UTF-16 respectively.
! 2676: ** ^(Memory to hold the error message string is managed internally.
! 2677: ** The application does not need to worry about freeing the result.
! 2678: ** However, the error string might be overwritten or deallocated by
! 2679: ** subsequent calls to other SQLite interface functions.)^
! 2680: **
! 2681: ** When the serialized [threading mode] is in use, it might be the
! 2682: ** case that a second error occurs on a separate thread in between
! 2683: ** the time of the first error and the call to these interfaces.
! 2684: ** When that happens, the second error will be reported since these
! 2685: ** interfaces always report the most recent result. To avoid
! 2686: ** this, each thread can obtain exclusive use of the [database connection] D
! 2687: ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
! 2688: ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
! 2689: ** all calls to the interfaces listed here are completed.
! 2690: **
! 2691: ** If an interface fails with SQLITE_MISUSE, that means the interface
! 2692: ** was invoked incorrectly by the application. In that case, the
! 2693: ** error code and message may or may not be set.
! 2694: */
! 2695: int sqlite3_errcode(sqlite3 *db);
! 2696: int sqlite3_extended_errcode(sqlite3 *db);
! 2697: const char *sqlite3_errmsg(sqlite3*);
! 2698: const void *sqlite3_errmsg16(sqlite3*);
! 2699:
! 2700: /*
! 2701: ** CAPI3REF: SQL Statement Object
! 2702: ** KEYWORDS: {prepared statement} {prepared statements}
! 2703: **
! 2704: ** An instance of this object represents a single SQL statement.
! 2705: ** This object is variously known as a "prepared statement" or a
! 2706: ** "compiled SQL statement" or simply as a "statement".
! 2707: **
! 2708: ** The life of a statement object goes something like this:
! 2709: **
! 2710: ** <ol>
! 2711: ** <li> Create the object using [sqlite3_prepare_v2()] or a related
! 2712: ** function.
! 2713: ** <li> Bind values to [host parameters] using the sqlite3_bind_*()
! 2714: ** interfaces.
! 2715: ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
! 2716: ** <li> Reset the statement using [sqlite3_reset()] then go back
! 2717: ** to step 2. Do this zero or more times.
! 2718: ** <li> Destroy the object using [sqlite3_finalize()].
! 2719: ** </ol>
! 2720: **
! 2721: ** Refer to documentation on individual methods above for additional
! 2722: ** information.
! 2723: */
! 2724: typedef struct sqlite3_stmt sqlite3_stmt;
! 2725:
! 2726: /*
! 2727: ** CAPI3REF: Run-time Limits
! 2728: **
! 2729: ** ^(This interface allows the size of various constructs to be limited
! 2730: ** on a connection by connection basis. The first parameter is the
! 2731: ** [database connection] whose limit is to be set or queried. The
! 2732: ** second parameter is one of the [limit categories] that define a
! 2733: ** class of constructs to be size limited. The third parameter is the
! 2734: ** new limit for that construct.)^
! 2735: **
! 2736: ** ^If the new limit is a negative number, the limit is unchanged.
! 2737: ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
! 2738: ** [limits | hard upper bound]
! 2739: ** set at compile-time by a C preprocessor macro called
! 2740: ** [limits | SQLITE_MAX_<i>NAME</i>].
! 2741: ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
! 2742: ** ^Attempts to increase a limit above its hard upper bound are
! 2743: ** silently truncated to the hard upper bound.
! 2744: **
! 2745: ** ^Regardless of whether or not the limit was changed, the
! 2746: ** [sqlite3_limit()] interface returns the prior value of the limit.
! 2747: ** ^Hence, to find the current value of a limit without changing it,
! 2748: ** simply invoke this interface with the third parameter set to -1.
! 2749: **
! 2750: ** Run-time limits are intended for use in applications that manage
! 2751: ** both their own internal database and also databases that are controlled
! 2752: ** by untrusted external sources. An example application might be a
! 2753: ** web browser that has its own databases for storing history and
! 2754: ** separate databases controlled by JavaScript applications downloaded
! 2755: ** off the Internet. The internal databases can be given the
! 2756: ** large, default limits. Databases managed by external sources can
! 2757: ** be given much smaller limits designed to prevent a denial of service
! 2758: ** attack. Developers might also want to use the [sqlite3_set_authorizer()]
! 2759: ** interface to further control untrusted SQL. The size of the database
! 2760: ** created by an untrusted script can be contained using the
! 2761: ** [max_page_count] [PRAGMA].
! 2762: **
! 2763: ** New run-time limit categories may be added in future releases.
! 2764: */
! 2765: int sqlite3_limit(sqlite3*, int id, int newVal);
! 2766:
! 2767: /*
! 2768: ** CAPI3REF: Run-Time Limit Categories
! 2769: ** KEYWORDS: {limit category} {*limit categories}
! 2770: **
! 2771: ** These constants define various performance limits
! 2772: ** that can be lowered at run-time using [sqlite3_limit()].
! 2773: ** The synopsis of the meanings of the various limits is shown below.
! 2774: ** Additional information is available at [limits | Limits in SQLite].
! 2775: **
! 2776: ** <dl>
! 2777: ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
! 2778: ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
! 2779: **
! 2780: ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
! 2781: ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
! 2782: **
! 2783: ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
! 2784: ** <dd>The maximum number of columns in a table definition or in the
! 2785: ** result set of a [SELECT] or the maximum number of columns in an index
! 2786: ** or in an ORDER BY or GROUP BY clause.</dd>)^
! 2787: **
! 2788: ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
! 2789: ** <dd>The maximum depth of the parse tree on any expression.</dd>)^
! 2790: **
! 2791: ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
! 2792: ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
! 2793: **
! 2794: ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
! 2795: ** <dd>The maximum number of instructions in a virtual machine program
! 2796: ** used to implement an SQL statement. This limit is not currently
! 2797: ** enforced, though that might be added in some future release of
! 2798: ** SQLite.</dd>)^
! 2799: **
! 2800: ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
! 2801: ** <dd>The maximum number of arguments on a function.</dd>)^
! 2802: **
! 2803: ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
! 2804: ** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
! 2805: **
! 2806: ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
! 2807: ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
! 2808: ** <dd>The maximum length of the pattern argument to the [LIKE] or
! 2809: ** [GLOB] operators.</dd>)^
! 2810: **
! 2811: ** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
! 2812: ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
! 2813: ** <dd>The maximum index number of any [parameter] in an SQL statement.)^
! 2814: **
! 2815: ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
! 2816: ** <dd>The maximum depth of recursion for triggers.</dd>)^
! 2817: ** </dl>
! 2818: */
! 2819: #define SQLITE_LIMIT_LENGTH 0
! 2820: #define SQLITE_LIMIT_SQL_LENGTH 1
! 2821: #define SQLITE_LIMIT_COLUMN 2
! 2822: #define SQLITE_LIMIT_EXPR_DEPTH 3
! 2823: #define SQLITE_LIMIT_COMPOUND_SELECT 4
! 2824: #define SQLITE_LIMIT_VDBE_OP 5
! 2825: #define SQLITE_LIMIT_FUNCTION_ARG 6
! 2826: #define SQLITE_LIMIT_ATTACHED 7
! 2827: #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
! 2828: #define SQLITE_LIMIT_VARIABLE_NUMBER 9
! 2829: #define SQLITE_LIMIT_TRIGGER_DEPTH 10
! 2830:
! 2831: /*
! 2832: ** CAPI3REF: Compiling An SQL Statement
! 2833: ** KEYWORDS: {SQL statement compiler}
! 2834: **
! 2835: ** To execute an SQL query, it must first be compiled into a byte-code
! 2836: ** program using one of these routines.
! 2837: **
! 2838: ** The first argument, "db", is a [database connection] obtained from a
! 2839: ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
! 2840: ** [sqlite3_open16()]. The database connection must not have been closed.
! 2841: **
! 2842: ** The second argument, "zSql", is the statement to be compiled, encoded
! 2843: ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
! 2844: ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
! 2845: ** use UTF-16.
! 2846: **
! 2847: ** ^If the nByte argument is less than zero, then zSql is read up to the
! 2848: ** first zero terminator. ^If nByte is non-negative, then it is the maximum
! 2849: ** number of bytes read from zSql. ^When nByte is non-negative, the
! 2850: ** zSql string ends at either the first '\000' or '\u0000' character or
! 2851: ** the nByte-th byte, whichever comes first. If the caller knows
! 2852: ** that the supplied string is nul-terminated, then there is a small
! 2853: ** performance advantage to be gained by passing an nByte parameter that
! 2854: ** is equal to the number of bytes in the input string <i>including</i>
! 2855: ** the nul-terminator bytes as this saves SQLite from having to
! 2856: ** make a copy of the input string.
! 2857: **
! 2858: ** ^If pzTail is not NULL then *pzTail is made to point to the first byte
! 2859: ** past the end of the first SQL statement in zSql. These routines only
! 2860: ** compile the first statement in zSql, so *pzTail is left pointing to
! 2861: ** what remains uncompiled.
! 2862: **
! 2863: ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
! 2864: ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
! 2865: ** to NULL. ^If the input text contains no SQL (if the input is an empty
! 2866: ** string or a comment) then *ppStmt is set to NULL.
! 2867: ** The calling procedure is responsible for deleting the compiled
! 2868: ** SQL statement using [sqlite3_finalize()] after it has finished with it.
! 2869: ** ppStmt may not be NULL.
! 2870: **
! 2871: ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
! 2872: ** otherwise an [error code] is returned.
! 2873: **
! 2874: ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
! 2875: ** recommended for all new programs. The two older interfaces are retained
! 2876: ** for backwards compatibility, but their use is discouraged.
! 2877: ** ^In the "v2" interfaces, the prepared statement
! 2878: ** that is returned (the [sqlite3_stmt] object) contains a copy of the
! 2879: ** original SQL text. This causes the [sqlite3_step()] interface to
! 2880: ** behave differently in three ways:
! 2881: **
! 2882: ** <ol>
! 2883: ** <li>
! 2884: ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
! 2885: ** always used to do, [sqlite3_step()] will automatically recompile the SQL
! 2886: ** statement and try to run it again.
! 2887: ** </li>
! 2888: **
! 2889: ** <li>
! 2890: ** ^When an error occurs, [sqlite3_step()] will return one of the detailed
! 2891: ** [error codes] or [extended error codes]. ^The legacy behavior was that
! 2892: ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
! 2893: ** and the application would have to make a second call to [sqlite3_reset()]
! 2894: ** in order to find the underlying cause of the problem. With the "v2" prepare
! 2895: ** interfaces, the underlying reason for the error is returned immediately.
! 2896: ** </li>
! 2897: **
! 2898: ** <li>
! 2899: ** ^If the specific value bound to [parameter | host parameter] in the
! 2900: ** WHERE clause might influence the choice of query plan for a statement,
! 2901: ** then the statement will be automatically recompiled, as if there had been
! 2902: ** a schema change, on the first [sqlite3_step()] call following any change
! 2903: ** to the [sqlite3_bind_text | bindings] of that [parameter].
! 2904: ** ^The specific value of WHERE-clause [parameter] might influence the
! 2905: ** choice of query plan if the parameter is the left-hand side of a [LIKE]
! 2906: ** or [GLOB] operator or if the parameter is compared to an indexed column
! 2907: ** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
! 2908: ** the
! 2909: ** </li>
! 2910: ** </ol>
! 2911: */
! 2912: int sqlite3_prepare(
! 2913: sqlite3 *db, /* Database handle */
! 2914: const char *zSql, /* SQL statement, UTF-8 encoded */
! 2915: int nByte, /* Maximum length of zSql in bytes. */
! 2916: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
! 2917: const char **pzTail /* OUT: Pointer to unused portion of zSql */
! 2918: );
! 2919: int sqlite3_prepare_v2(
! 2920: sqlite3 *db, /* Database handle */
! 2921: const char *zSql, /* SQL statement, UTF-8 encoded */
! 2922: int nByte, /* Maximum length of zSql in bytes. */
! 2923: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
! 2924: const char **pzTail /* OUT: Pointer to unused portion of zSql */
! 2925: );
! 2926: int sqlite3_prepare16(
! 2927: sqlite3 *db, /* Database handle */
! 2928: const void *zSql, /* SQL statement, UTF-16 encoded */
! 2929: int nByte, /* Maximum length of zSql in bytes. */
! 2930: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
! 2931: const void **pzTail /* OUT: Pointer to unused portion of zSql */
! 2932: );
! 2933: int sqlite3_prepare16_v2(
! 2934: sqlite3 *db, /* Database handle */
! 2935: const void *zSql, /* SQL statement, UTF-16 encoded */
! 2936: int nByte, /* Maximum length of zSql in bytes. */
! 2937: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
! 2938: const void **pzTail /* OUT: Pointer to unused portion of zSql */
! 2939: );
! 2940:
! 2941: /*
! 2942: ** CAPI3REF: Retrieving Statement SQL
! 2943: **
! 2944: ** ^This interface can be used to retrieve a saved copy of the original
! 2945: ** SQL text used to create a [prepared statement] if that statement was
! 2946: ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
! 2947: */
! 2948: const char *sqlite3_sql(sqlite3_stmt *pStmt);
! 2949:
! 2950: /*
! 2951: ** CAPI3REF: Determine If An SQL Statement Writes The Database
! 2952: **
! 2953: ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
! 2954: ** and only if the [prepared statement] X makes no direct changes to
! 2955: ** the content of the database file.
! 2956: **
! 2957: ** Note that [application-defined SQL functions] or
! 2958: ** [virtual tables] might change the database indirectly as a side effect.
! 2959: ** ^(For example, if an application defines a function "eval()" that
! 2960: ** calls [sqlite3_exec()], then the following SQL statement would
! 2961: ** change the database file through side-effects:
! 2962: **
! 2963: ** <blockquote><pre>
! 2964: ** SELECT eval('DELETE FROM t1') FROM t2;
! 2965: ** </pre></blockquote>
! 2966: **
! 2967: ** But because the [SELECT] statement does not change the database file
! 2968: ** directly, sqlite3_stmt_readonly() would still return true.)^
! 2969: **
! 2970: ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
! 2971: ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
! 2972: ** since the statements themselves do not actually modify the database but
! 2973: ** rather they control the timing of when other statements modify the
! 2974: ** database. ^The [ATTACH] and [DETACH] statements also cause
! 2975: ** sqlite3_stmt_readonly() to return true since, while those statements
! 2976: ** change the configuration of a database connection, they do not make
! 2977: ** changes to the content of the database files on disk.
! 2978: */
! 2979: int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
! 2980:
! 2981: /*
! 2982: ** CAPI3REF: Determine If A Prepared Statement Has Been Reset
! 2983: **
! 2984: ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
! 2985: ** [prepared statement] S has been stepped at least once using
! 2986: ** [sqlite3_step(S)] but has not run to completion and/or has not
! 2987: ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
! 2988: ** interface returns false if S is a NULL pointer. If S is not a
! 2989: ** NULL pointer and is not a pointer to a valid [prepared statement]
! 2990: ** object, then the behavior is undefined and probably undesirable.
! 2991: **
! 2992: ** This interface can be used in combination [sqlite3_next_stmt()]
! 2993: ** to locate all prepared statements associated with a database
! 2994: ** connection that are in need of being reset. This can be used,
! 2995: ** for example, in diagnostic routines to search for prepared
! 2996: ** statements that are holding a transaction open.
! 2997: */
! 2998: int sqlite3_stmt_busy(sqlite3_stmt*);
! 2999:
! 3000: /*
! 3001: ** CAPI3REF: Dynamically Typed Value Object
! 3002: ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
! 3003: **
! 3004: ** SQLite uses the sqlite3_value object to represent all values
! 3005: ** that can be stored in a database table. SQLite uses dynamic typing
! 3006: ** for the values it stores. ^Values stored in sqlite3_value objects
! 3007: ** can be integers, floating point values, strings, BLOBs, or NULL.
! 3008: **
! 3009: ** An sqlite3_value object may be either "protected" or "unprotected".
! 3010: ** Some interfaces require a protected sqlite3_value. Other interfaces
! 3011: ** will accept either a protected or an unprotected sqlite3_value.
! 3012: ** Every interface that accepts sqlite3_value arguments specifies
! 3013: ** whether or not it requires a protected sqlite3_value.
! 3014: **
! 3015: ** The terms "protected" and "unprotected" refer to whether or not
! 3016: ** a mutex is held. An internal mutex is held for a protected
! 3017: ** sqlite3_value object but no mutex is held for an unprotected
! 3018: ** sqlite3_value object. If SQLite is compiled to be single-threaded
! 3019: ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
! 3020: ** or if SQLite is run in one of reduced mutex modes
! 3021: ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
! 3022: ** then there is no distinction between protected and unprotected
! 3023: ** sqlite3_value objects and they can be used interchangeably. However,
! 3024: ** for maximum code portability it is recommended that applications
! 3025: ** still make the distinction between protected and unprotected
! 3026: ** sqlite3_value objects even when not strictly required.
! 3027: **
! 3028: ** ^The sqlite3_value objects that are passed as parameters into the
! 3029: ** implementation of [application-defined SQL functions] are protected.
! 3030: ** ^The sqlite3_value object returned by
! 3031: ** [sqlite3_column_value()] is unprotected.
! 3032: ** Unprotected sqlite3_value objects may only be used with
! 3033: ** [sqlite3_result_value()] and [sqlite3_bind_value()].
! 3034: ** The [sqlite3_value_blob | sqlite3_value_type()] family of
! 3035: ** interfaces require protected sqlite3_value objects.
! 3036: */
! 3037: typedef struct Mem sqlite3_value;
! 3038:
! 3039: /*
! 3040: ** CAPI3REF: SQL Function Context Object
! 3041: **
! 3042: ** The context in which an SQL function executes is stored in an
! 3043: ** sqlite3_context object. ^A pointer to an sqlite3_context object
! 3044: ** is always first parameter to [application-defined SQL functions].
! 3045: ** The application-defined SQL function implementation will pass this
! 3046: ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
! 3047: ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
! 3048: ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
! 3049: ** and/or [sqlite3_set_auxdata()].
! 3050: */
! 3051: typedef struct sqlite3_context sqlite3_context;
! 3052:
! 3053: /*
! 3054: ** CAPI3REF: Binding Values To Prepared Statements
! 3055: ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
! 3056: ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
! 3057: **
! 3058: ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
! 3059: ** literals may be replaced by a [parameter] that matches one of following
! 3060: ** templates:
! 3061: **
! 3062: ** <ul>
! 3063: ** <li> ?
! 3064: ** <li> ?NNN
! 3065: ** <li> :VVV
! 3066: ** <li> @VVV
! 3067: ** <li> $VVV
! 3068: ** </ul>
! 3069: **
! 3070: ** In the templates above, NNN represents an integer literal,
! 3071: ** and VVV represents an alphanumeric identifier.)^ ^The values of these
! 3072: ** parameters (also called "host parameter names" or "SQL parameters")
! 3073: ** can be set using the sqlite3_bind_*() routines defined here.
! 3074: **
! 3075: ** ^The first argument to the sqlite3_bind_*() routines is always
! 3076: ** a pointer to the [sqlite3_stmt] object returned from
! 3077: ** [sqlite3_prepare_v2()] or its variants.
! 3078: **
! 3079: ** ^The second argument is the index of the SQL parameter to be set.
! 3080: ** ^The leftmost SQL parameter has an index of 1. ^When the same named
! 3081: ** SQL parameter is used more than once, second and subsequent
! 3082: ** occurrences have the same index as the first occurrence.
! 3083: ** ^The index for named parameters can be looked up using the
! 3084: ** [sqlite3_bind_parameter_index()] API if desired. ^The index
! 3085: ** for "?NNN" parameters is the value of NNN.
! 3086: ** ^The NNN value must be between 1 and the [sqlite3_limit()]
! 3087: ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
! 3088: **
! 3089: ** ^The third argument is the value to bind to the parameter.
! 3090: **
! 3091: ** ^(In those routines that have a fourth argument, its value is the
! 3092: ** number of bytes in the parameter. To be clear: the value is the
! 3093: ** number of <u>bytes</u> in the value, not the number of characters.)^
! 3094: ** ^If the fourth parameter is negative, the length of the string is
! 3095: ** the number of bytes up to the first zero terminator.
! 3096: ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
! 3097: ** or sqlite3_bind_text16() then that parameter must be the byte offset
! 3098: ** where the NUL terminator would occur assuming the string were NUL
! 3099: ** terminated. If any NUL characters occur at byte offsets less than
! 3100: ** the value of the fourth parameter then the resulting string value will
! 3101: ** contain embedded NULs. The result of expressions involving strings
! 3102: ** with embedded NULs is undefined.
! 3103: **
! 3104: ** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
! 3105: ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
! 3106: ** string after SQLite has finished with it. ^The destructor is called
! 3107: ** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
! 3108: ** sqlite3_bind_text(), or sqlite3_bind_text16() fails.
! 3109: ** ^If the fifth argument is
! 3110: ** the special value [SQLITE_STATIC], then SQLite assumes that the
! 3111: ** information is in static, unmanaged space and does not need to be freed.
! 3112: ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
! 3113: ** SQLite makes its own private copy of the data immediately, before
! 3114: ** the sqlite3_bind_*() routine returns.
! 3115: **
! 3116: ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
! 3117: ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
! 3118: ** (just an integer to hold its size) while it is being processed.
! 3119: ** Zeroblobs are intended to serve as placeholders for BLOBs whose
! 3120: ** content is later written using
! 3121: ** [sqlite3_blob_open | incremental BLOB I/O] routines.
! 3122: ** ^A negative value for the zeroblob results in a zero-length BLOB.
! 3123: **
! 3124: ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
! 3125: ** for the [prepared statement] or with a prepared statement for which
! 3126: ** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
! 3127: ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
! 3128: ** routine is passed a [prepared statement] that has been finalized, the
! 3129: ** result is undefined and probably harmful.
! 3130: **
! 3131: ** ^Bindings are not cleared by the [sqlite3_reset()] routine.
! 3132: ** ^Unbound parameters are interpreted as NULL.
! 3133: **
! 3134: ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
! 3135: ** [error code] if anything goes wrong.
! 3136: ** ^[SQLITE_RANGE] is returned if the parameter
! 3137: ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
! 3138: **
! 3139: ** See also: [sqlite3_bind_parameter_count()],
! 3140: ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
! 3141: */
! 3142: int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
! 3143: int sqlite3_bind_double(sqlite3_stmt*, int, double);
! 3144: int sqlite3_bind_int(sqlite3_stmt*, int, int);
! 3145: int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
! 3146: int sqlite3_bind_null(sqlite3_stmt*, int);
! 3147: int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
! 3148: int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
! 3149: int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
! 3150: int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
! 3151:
! 3152: /*
! 3153: ** CAPI3REF: Number Of SQL Parameters
! 3154: **
! 3155: ** ^This routine can be used to find the number of [SQL parameters]
! 3156: ** in a [prepared statement]. SQL parameters are tokens of the
! 3157: ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
! 3158: ** placeholders for values that are [sqlite3_bind_blob | bound]
! 3159: ** to the parameters at a later time.
! 3160: **
! 3161: ** ^(This routine actually returns the index of the largest (rightmost)
! 3162: ** parameter. For all forms except ?NNN, this will correspond to the
! 3163: ** number of unique parameters. If parameters of the ?NNN form are used,
! 3164: ** there may be gaps in the list.)^
! 3165: **
! 3166: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
! 3167: ** [sqlite3_bind_parameter_name()], and
! 3168: ** [sqlite3_bind_parameter_index()].
! 3169: */
! 3170: int sqlite3_bind_parameter_count(sqlite3_stmt*);
! 3171:
! 3172: /*
! 3173: ** CAPI3REF: Name Of A Host Parameter
! 3174: **
! 3175: ** ^The sqlite3_bind_parameter_name(P,N) interface returns
! 3176: ** the name of the N-th [SQL parameter] in the [prepared statement] P.
! 3177: ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
! 3178: ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
! 3179: ** respectively.
! 3180: ** In other words, the initial ":" or "$" or "@" or "?"
! 3181: ** is included as part of the name.)^
! 3182: ** ^Parameters of the form "?" without a following integer have no name
! 3183: ** and are referred to as "nameless" or "anonymous parameters".
! 3184: **
! 3185: ** ^The first host parameter has an index of 1, not 0.
! 3186: **
! 3187: ** ^If the value N is out of range or if the N-th parameter is
! 3188: ** nameless, then NULL is returned. ^The returned string is
! 3189: ** always in UTF-8 encoding even if the named parameter was
! 3190: ** originally specified as UTF-16 in [sqlite3_prepare16()] or
! 3191: ** [sqlite3_prepare16_v2()].
! 3192: **
! 3193: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
! 3194: ** [sqlite3_bind_parameter_count()], and
! 3195: ** [sqlite3_bind_parameter_index()].
! 3196: */
! 3197: const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
! 3198:
! 3199: /*
! 3200: ** CAPI3REF: Index Of A Parameter With A Given Name
! 3201: **
! 3202: ** ^Return the index of an SQL parameter given its name. ^The
! 3203: ** index value returned is suitable for use as the second
! 3204: ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
! 3205: ** is returned if no matching parameter is found. ^The parameter
! 3206: ** name must be given in UTF-8 even if the original statement
! 3207: ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
! 3208: **
! 3209: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
! 3210: ** [sqlite3_bind_parameter_count()], and
! 3211: ** [sqlite3_bind_parameter_index()].
! 3212: */
! 3213: int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
! 3214:
! 3215: /*
! 3216: ** CAPI3REF: Reset All Bindings On A Prepared Statement
! 3217: **
! 3218: ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
! 3219: ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
! 3220: ** ^Use this routine to reset all host parameters to NULL.
! 3221: */
! 3222: int sqlite3_clear_bindings(sqlite3_stmt*);
! 3223:
! 3224: /*
! 3225: ** CAPI3REF: Number Of Columns In A Result Set
! 3226: **
! 3227: ** ^Return the number of columns in the result set returned by the
! 3228: ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
! 3229: ** statement that does not return data (for example an [UPDATE]).
! 3230: **
! 3231: ** See also: [sqlite3_data_count()]
! 3232: */
! 3233: int sqlite3_column_count(sqlite3_stmt *pStmt);
! 3234:
! 3235: /*
! 3236: ** CAPI3REF: Column Names In A Result Set
! 3237: **
! 3238: ** ^These routines return the name assigned to a particular column
! 3239: ** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
! 3240: ** interface returns a pointer to a zero-terminated UTF-8 string
! 3241: ** and sqlite3_column_name16() returns a pointer to a zero-terminated
! 3242: ** UTF-16 string. ^The first parameter is the [prepared statement]
! 3243: ** that implements the [SELECT] statement. ^The second parameter is the
! 3244: ** column number. ^The leftmost column is number 0.
! 3245: **
! 3246: ** ^The returned string pointer is valid until either the [prepared statement]
! 3247: ** is destroyed by [sqlite3_finalize()] or until the statement is automatically
! 3248: ** reprepared by the first call to [sqlite3_step()] for a particular run
! 3249: ** or until the next call to
! 3250: ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
! 3251: **
! 3252: ** ^If sqlite3_malloc() fails during the processing of either routine
! 3253: ** (for example during a conversion from UTF-8 to UTF-16) then a
! 3254: ** NULL pointer is returned.
! 3255: **
! 3256: ** ^The name of a result column is the value of the "AS" clause for
! 3257: ** that column, if there is an AS clause. If there is no AS clause
! 3258: ** then the name of the column is unspecified and may change from
! 3259: ** one release of SQLite to the next.
! 3260: */
! 3261: const char *sqlite3_column_name(sqlite3_stmt*, int N);
! 3262: const void *sqlite3_column_name16(sqlite3_stmt*, int N);
! 3263:
! 3264: /*
! 3265: ** CAPI3REF: Source Of Data In A Query Result
! 3266: **
! 3267: ** ^These routines provide a means to determine the database, table, and
! 3268: ** table column that is the origin of a particular result column in
! 3269: ** [SELECT] statement.
! 3270: ** ^The name of the database or table or column can be returned as
! 3271: ** either a UTF-8 or UTF-16 string. ^The _database_ routines return
! 3272: ** the database name, the _table_ routines return the table name, and
! 3273: ** the origin_ routines return the column name.
! 3274: ** ^The returned string is valid until the [prepared statement] is destroyed
! 3275: ** using [sqlite3_finalize()] or until the statement is automatically
! 3276: ** reprepared by the first call to [sqlite3_step()] for a particular run
! 3277: ** or until the same information is requested
! 3278: ** again in a different encoding.
! 3279: **
! 3280: ** ^The names returned are the original un-aliased names of the
! 3281: ** database, table, and column.
! 3282: **
! 3283: ** ^The first argument to these interfaces is a [prepared statement].
! 3284: ** ^These functions return information about the Nth result column returned by
! 3285: ** the statement, where N is the second function argument.
! 3286: ** ^The left-most column is column 0 for these routines.
! 3287: **
! 3288: ** ^If the Nth column returned by the statement is an expression or
! 3289: ** subquery and is not a column value, then all of these functions return
! 3290: ** NULL. ^These routine might also return NULL if a memory allocation error
! 3291: ** occurs. ^Otherwise, they return the name of the attached database, table,
! 3292: ** or column that query result column was extracted from.
! 3293: **
! 3294: ** ^As with all other SQLite APIs, those whose names end with "16" return
! 3295: ** UTF-16 encoded strings and the other functions return UTF-8.
! 3296: **
! 3297: ** ^These APIs are only available if the library was compiled with the
! 3298: ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
! 3299: **
! 3300: ** If two or more threads call one or more of these routines against the same
! 3301: ** prepared statement and column at the same time then the results are
! 3302: ** undefined.
! 3303: **
! 3304: ** If two or more threads call one or more
! 3305: ** [sqlite3_column_database_name | column metadata interfaces]
! 3306: ** for the same [prepared statement] and result column
! 3307: ** at the same time then the results are undefined.
! 3308: */
! 3309: const char *sqlite3_column_database_name(sqlite3_stmt*,int);
! 3310: const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
! 3311: const char *sqlite3_column_table_name(sqlite3_stmt*,int);
! 3312: const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
! 3313: const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
! 3314: const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
! 3315:
! 3316: /*
! 3317: ** CAPI3REF: Declared Datatype Of A Query Result
! 3318: **
! 3319: ** ^(The first parameter is a [prepared statement].
! 3320: ** If this statement is a [SELECT] statement and the Nth column of the
! 3321: ** returned result set of that [SELECT] is a table column (not an
! 3322: ** expression or subquery) then the declared type of the table
! 3323: ** column is returned.)^ ^If the Nth column of the result set is an
! 3324: ** expression or subquery, then a NULL pointer is returned.
! 3325: ** ^The returned string is always UTF-8 encoded.
! 3326: **
! 3327: ** ^(For example, given the database schema:
! 3328: **
! 3329: ** CREATE TABLE t1(c1 VARIANT);
! 3330: **
! 3331: ** and the following statement to be compiled:
! 3332: **
! 3333: ** SELECT c1 + 1, c1 FROM t1;
! 3334: **
! 3335: ** this routine would return the string "VARIANT" for the second result
! 3336: ** column (i==1), and a NULL pointer for the first result column (i==0).)^
! 3337: **
! 3338: ** ^SQLite uses dynamic run-time typing. ^So just because a column
! 3339: ** is declared to contain a particular type does not mean that the
! 3340: ** data stored in that column is of the declared type. SQLite is
! 3341: ** strongly typed, but the typing is dynamic not static. ^Type
! 3342: ** is associated with individual values, not with the containers
! 3343: ** used to hold those values.
! 3344: */
! 3345: const char *sqlite3_column_decltype(sqlite3_stmt*,int);
! 3346: const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
! 3347:
! 3348: /*
! 3349: ** CAPI3REF: Evaluate An SQL Statement
! 3350: **
! 3351: ** After a [prepared statement] has been prepared using either
! 3352: ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
! 3353: ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
! 3354: ** must be called one or more times to evaluate the statement.
! 3355: **
! 3356: ** The details of the behavior of the sqlite3_step() interface depend
! 3357: ** on whether the statement was prepared using the newer "v2" interface
! 3358: ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
! 3359: ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
! 3360: ** new "v2" interface is recommended for new applications but the legacy
! 3361: ** interface will continue to be supported.
! 3362: **
! 3363: ** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
! 3364: ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
! 3365: ** ^With the "v2" interface, any of the other [result codes] or
! 3366: ** [extended result codes] might be returned as well.
! 3367: **
! 3368: ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
! 3369: ** database locks it needs to do its job. ^If the statement is a [COMMIT]
! 3370: ** or occurs outside of an explicit transaction, then you can retry the
! 3371: ** statement. If the statement is not a [COMMIT] and occurs within an
! 3372: ** explicit transaction then you should rollback the transaction before
! 3373: ** continuing.
! 3374: **
! 3375: ** ^[SQLITE_DONE] means that the statement has finished executing
! 3376: ** successfully. sqlite3_step() should not be called again on this virtual
! 3377: ** machine without first calling [sqlite3_reset()] to reset the virtual
! 3378: ** machine back to its initial state.
! 3379: **
! 3380: ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
! 3381: ** is returned each time a new row of data is ready for processing by the
! 3382: ** caller. The values may be accessed using the [column access functions].
! 3383: ** sqlite3_step() is called again to retrieve the next row of data.
! 3384: **
! 3385: ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
! 3386: ** violation) has occurred. sqlite3_step() should not be called again on
! 3387: ** the VM. More information may be found by calling [sqlite3_errmsg()].
! 3388: ** ^With the legacy interface, a more specific error code (for example,
! 3389: ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
! 3390: ** can be obtained by calling [sqlite3_reset()] on the
! 3391: ** [prepared statement]. ^In the "v2" interface,
! 3392: ** the more specific error code is returned directly by sqlite3_step().
! 3393: **
! 3394: ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
! 3395: ** Perhaps it was called on a [prepared statement] that has
! 3396: ** already been [sqlite3_finalize | finalized] or on one that had
! 3397: ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
! 3398: ** be the case that the same database connection is being used by two or
! 3399: ** more threads at the same moment in time.
! 3400: **
! 3401: ** For all versions of SQLite up to and including 3.6.23.1, a call to
! 3402: ** [sqlite3_reset()] was required after sqlite3_step() returned anything
! 3403: ** other than [SQLITE_ROW] before any subsequent invocation of
! 3404: ** sqlite3_step(). Failure to reset the prepared statement using
! 3405: ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
! 3406: ** sqlite3_step(). But after version 3.6.23.1, sqlite3_step() began
! 3407: ** calling [sqlite3_reset()] automatically in this circumstance rather
! 3408: ** than returning [SQLITE_MISUSE]. This is not considered a compatibility
! 3409: ** break because any application that ever receives an SQLITE_MISUSE error
! 3410: ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
! 3411: ** can be used to restore the legacy behavior.
! 3412: **
! 3413: ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
! 3414: ** API always returns a generic error code, [SQLITE_ERROR], following any
! 3415: ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
! 3416: ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
! 3417: ** specific [error codes] that better describes the error.
! 3418: ** We admit that this is a goofy design. The problem has been fixed
! 3419: ** with the "v2" interface. If you prepare all of your SQL statements
! 3420: ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
! 3421: ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
! 3422: ** then the more specific [error codes] are returned directly
! 3423: ** by sqlite3_step(). The use of the "v2" interface is recommended.
! 3424: */
! 3425: int sqlite3_step(sqlite3_stmt*);
! 3426:
! 3427: /*
! 3428: ** CAPI3REF: Number of columns in a result set
! 3429: **
! 3430: ** ^The sqlite3_data_count(P) interface returns the number of columns in the
! 3431: ** current row of the result set of [prepared statement] P.
! 3432: ** ^If prepared statement P does not have results ready to return
! 3433: ** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
! 3434: ** interfaces) then sqlite3_data_count(P) returns 0.
! 3435: ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
! 3436: ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
! 3437: ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
! 3438: ** will return non-zero if previous call to [sqlite3_step](P) returned
! 3439: ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
! 3440: ** where it always returns zero since each step of that multi-step
! 3441: ** pragma returns 0 columns of data.
! 3442: **
! 3443: ** See also: [sqlite3_column_count()]
! 3444: */
! 3445: int sqlite3_data_count(sqlite3_stmt *pStmt);
! 3446:
! 3447: /*
! 3448: ** CAPI3REF: Fundamental Datatypes
! 3449: ** KEYWORDS: SQLITE_TEXT
! 3450: **
! 3451: ** ^(Every value in SQLite has one of five fundamental datatypes:
! 3452: **
! 3453: ** <ul>
! 3454: ** <li> 64-bit signed integer
! 3455: ** <li> 64-bit IEEE floating point number
! 3456: ** <li> string
! 3457: ** <li> BLOB
! 3458: ** <li> NULL
! 3459: ** </ul>)^
! 3460: **
! 3461: ** These constants are codes for each of those types.
! 3462: **
! 3463: ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
! 3464: ** for a completely different meaning. Software that links against both
! 3465: ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
! 3466: ** SQLITE_TEXT.
! 3467: */
! 3468: #define SQLITE_INTEGER 1
! 3469: #define SQLITE_FLOAT 2
! 3470: #define SQLITE_BLOB 4
! 3471: #define SQLITE_NULL 5
! 3472: #ifdef SQLITE_TEXT
! 3473: # undef SQLITE_TEXT
! 3474: #else
! 3475: # define SQLITE_TEXT 3
! 3476: #endif
! 3477: #define SQLITE3_TEXT 3
! 3478:
! 3479: /*
! 3480: ** CAPI3REF: Result Values From A Query
! 3481: ** KEYWORDS: {column access functions}
! 3482: **
! 3483: ** These routines form the "result set" interface.
! 3484: **
! 3485: ** ^These routines return information about a single column of the current
! 3486: ** result row of a query. ^In every case the first argument is a pointer
! 3487: ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
! 3488: ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
! 3489: ** and the second argument is the index of the column for which information
! 3490: ** should be returned. ^The leftmost column of the result set has the index 0.
! 3491: ** ^The number of columns in the result can be determined using
! 3492: ** [sqlite3_column_count()].
! 3493: **
! 3494: ** If the SQL statement does not currently point to a valid row, or if the
! 3495: ** column index is out of range, the result is undefined.
! 3496: ** These routines may only be called when the most recent call to
! 3497: ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
! 3498: ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
! 3499: ** If any of these routines are called after [sqlite3_reset()] or
! 3500: ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
! 3501: ** something other than [SQLITE_ROW], the results are undefined.
! 3502: ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
! 3503: ** are called from a different thread while any of these routines
! 3504: ** are pending, then the results are undefined.
! 3505: **
! 3506: ** ^The sqlite3_column_type() routine returns the
! 3507: ** [SQLITE_INTEGER | datatype code] for the initial data type
! 3508: ** of the result column. ^The returned value is one of [SQLITE_INTEGER],
! 3509: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
! 3510: ** returned by sqlite3_column_type() is only meaningful if no type
! 3511: ** conversions have occurred as described below. After a type conversion,
! 3512: ** the value returned by sqlite3_column_type() is undefined. Future
! 3513: ** versions of SQLite may change the behavior of sqlite3_column_type()
! 3514: ** following a type conversion.
! 3515: **
! 3516: ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
! 3517: ** routine returns the number of bytes in that BLOB or string.
! 3518: ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
! 3519: ** the string to UTF-8 and then returns the number of bytes.
! 3520: ** ^If the result is a numeric value then sqlite3_column_bytes() uses
! 3521: ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
! 3522: ** the number of bytes in that string.
! 3523: ** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
! 3524: **
! 3525: ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
! 3526: ** routine returns the number of bytes in that BLOB or string.
! 3527: ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
! 3528: ** the string to UTF-16 and then returns the number of bytes.
! 3529: ** ^If the result is a numeric value then sqlite3_column_bytes16() uses
! 3530: ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
! 3531: ** the number of bytes in that string.
! 3532: ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
! 3533: **
! 3534: ** ^The values returned by [sqlite3_column_bytes()] and
! 3535: ** [sqlite3_column_bytes16()] do not include the zero terminators at the end
! 3536: ** of the string. ^For clarity: the values returned by
! 3537: ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
! 3538: ** bytes in the string, not the number of characters.
! 3539: **
! 3540: ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
! 3541: ** even empty strings, are always zero-terminated. ^The return
! 3542: ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
! 3543: **
! 3544: ** ^The object returned by [sqlite3_column_value()] is an
! 3545: ** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
! 3546: ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
! 3547: ** If the [unprotected sqlite3_value] object returned by
! 3548: ** [sqlite3_column_value()] is used in any other way, including calls
! 3549: ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
! 3550: ** or [sqlite3_value_bytes()], then the behavior is undefined.
! 3551: **
! 3552: ** These routines attempt to convert the value where appropriate. ^For
! 3553: ** example, if the internal representation is FLOAT and a text result
! 3554: ** is requested, [sqlite3_snprintf()] is used internally to perform the
! 3555: ** conversion automatically. ^(The following table details the conversions
! 3556: ** that are applied:
! 3557: **
! 3558: ** <blockquote>
! 3559: ** <table border="1">
! 3560: ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
! 3561: **
! 3562: ** <tr><td> NULL <td> INTEGER <td> Result is 0
! 3563: ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
! 3564: ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
! 3565: ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
! 3566: ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
! 3567: ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
! 3568: ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
! 3569: ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
! 3570: ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
! 3571: ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
! 3572: ** <tr><td> TEXT <td> INTEGER <td> Use atoi()
! 3573: ** <tr><td> TEXT <td> FLOAT <td> Use atof()
! 3574: ** <tr><td> TEXT <td> BLOB <td> No change
! 3575: ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
! 3576: ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
! 3577: ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
! 3578: ** </table>
! 3579: ** </blockquote>)^
! 3580: **
! 3581: ** The table above makes reference to standard C library functions atoi()
! 3582: ** and atof(). SQLite does not really use these functions. It has its
! 3583: ** own equivalent internal routines. The atoi() and atof() names are
! 3584: ** used in the table for brevity and because they are familiar to most
! 3585: ** C programmers.
! 3586: **
! 3587: ** Note that when type conversions occur, pointers returned by prior
! 3588: ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
! 3589: ** sqlite3_column_text16() may be invalidated.
! 3590: ** Type conversions and pointer invalidations might occur
! 3591: ** in the following cases:
! 3592: **
! 3593: ** <ul>
! 3594: ** <li> The initial content is a BLOB and sqlite3_column_text() or
! 3595: ** sqlite3_column_text16() is called. A zero-terminator might
! 3596: ** need to be added to the string.</li>
! 3597: ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
! 3598: ** sqlite3_column_text16() is called. The content must be converted
! 3599: ** to UTF-16.</li>
! 3600: ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
! 3601: ** sqlite3_column_text() is called. The content must be converted
! 3602: ** to UTF-8.</li>
! 3603: ** </ul>
! 3604: **
! 3605: ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
! 3606: ** not invalidate a prior pointer, though of course the content of the buffer
! 3607: ** that the prior pointer references will have been modified. Other kinds
! 3608: ** of conversion are done in place when it is possible, but sometimes they
! 3609: ** are not possible and in those cases prior pointers are invalidated.
! 3610: **
! 3611: ** The safest and easiest to remember policy is to invoke these routines
! 3612: ** in one of the following ways:
! 3613: **
! 3614: ** <ul>
! 3615: ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
! 3616: ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
! 3617: ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
! 3618: ** </ul>
! 3619: **
! 3620: ** In other words, you should call sqlite3_column_text(),
! 3621: ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
! 3622: ** into the desired format, then invoke sqlite3_column_bytes() or
! 3623: ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
! 3624: ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
! 3625: ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
! 3626: ** with calls to sqlite3_column_bytes().
! 3627: **
! 3628: ** ^The pointers returned are valid until a type conversion occurs as
! 3629: ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
! 3630: ** [sqlite3_finalize()] is called. ^The memory space used to hold strings
! 3631: ** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
! 3632: ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
! 3633: ** [sqlite3_free()].
! 3634: **
! 3635: ** ^(If a memory allocation error occurs during the evaluation of any
! 3636: ** of these routines, a default value is returned. The default value
! 3637: ** is either the integer 0, the floating point number 0.0, or a NULL
! 3638: ** pointer. Subsequent calls to [sqlite3_errcode()] will return
! 3639: ** [SQLITE_NOMEM].)^
! 3640: */
! 3641: const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
! 3642: int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
! 3643: int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
! 3644: double sqlite3_column_double(sqlite3_stmt*, int iCol);
! 3645: int sqlite3_column_int(sqlite3_stmt*, int iCol);
! 3646: sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
! 3647: const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
! 3648: const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
! 3649: int sqlite3_column_type(sqlite3_stmt*, int iCol);
! 3650: sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
! 3651:
! 3652: /*
! 3653: ** CAPI3REF: Destroy A Prepared Statement Object
! 3654: **
! 3655: ** ^The sqlite3_finalize() function is called to delete a [prepared statement].
! 3656: ** ^If the most recent evaluation of the statement encountered no errors
! 3657: ** or if the statement is never been evaluated, then sqlite3_finalize() returns
! 3658: ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
! 3659: ** sqlite3_finalize(S) returns the appropriate [error code] or
! 3660: ** [extended error code].
! 3661: **
! 3662: ** ^The sqlite3_finalize(S) routine can be called at any point during
! 3663: ** the life cycle of [prepared statement] S:
! 3664: ** before statement S is ever evaluated, after
! 3665: ** one or more calls to [sqlite3_reset()], or after any call
! 3666: ** to [sqlite3_step()] regardless of whether or not the statement has
! 3667: ** completed execution.
! 3668: **
! 3669: ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
! 3670: **
! 3671: ** The application must finalize every [prepared statement] in order to avoid
! 3672: ** resource leaks. It is a grievous error for the application to try to use
! 3673: ** a prepared statement after it has been finalized. Any use of a prepared
! 3674: ** statement after it has been finalized can result in undefined and
! 3675: ** undesirable behavior such as segfaults and heap corruption.
! 3676: */
! 3677: int sqlite3_finalize(sqlite3_stmt *pStmt);
! 3678:
! 3679: /*
! 3680: ** CAPI3REF: Reset A Prepared Statement Object
! 3681: **
! 3682: ** The sqlite3_reset() function is called to reset a [prepared statement]
! 3683: ** object back to its initial state, ready to be re-executed.
! 3684: ** ^Any SQL statement variables that had values bound to them using
! 3685: ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
! 3686: ** Use [sqlite3_clear_bindings()] to reset the bindings.
! 3687: **
! 3688: ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
! 3689: ** back to the beginning of its program.
! 3690: **
! 3691: ** ^If the most recent call to [sqlite3_step(S)] for the
! 3692: ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
! 3693: ** or if [sqlite3_step(S)] has never before been called on S,
! 3694: ** then [sqlite3_reset(S)] returns [SQLITE_OK].
! 3695: **
! 3696: ** ^If the most recent call to [sqlite3_step(S)] for the
! 3697: ** [prepared statement] S indicated an error, then
! 3698: ** [sqlite3_reset(S)] returns an appropriate [error code].
! 3699: **
! 3700: ** ^The [sqlite3_reset(S)] interface does not change the values
! 3701: ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
! 3702: */
! 3703: int sqlite3_reset(sqlite3_stmt *pStmt);
! 3704:
! 3705: /*
! 3706: ** CAPI3REF: Create Or Redefine SQL Functions
! 3707: ** KEYWORDS: {function creation routines}
! 3708: ** KEYWORDS: {application-defined SQL function}
! 3709: ** KEYWORDS: {application-defined SQL functions}
! 3710: **
! 3711: ** ^These functions (collectively known as "function creation routines")
! 3712: ** are used to add SQL functions or aggregates or to redefine the behavior
! 3713: ** of existing SQL functions or aggregates. The only differences between
! 3714: ** these routines are the text encoding expected for
! 3715: ** the second parameter (the name of the function being created)
! 3716: ** and the presence or absence of a destructor callback for
! 3717: ** the application data pointer.
! 3718: **
! 3719: ** ^The first parameter is the [database connection] to which the SQL
! 3720: ** function is to be added. ^If an application uses more than one database
! 3721: ** connection then application-defined SQL functions must be added
! 3722: ** to each database connection separately.
! 3723: **
! 3724: ** ^The second parameter is the name of the SQL function to be created or
! 3725: ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
! 3726: ** representation, exclusive of the zero-terminator. ^Note that the name
! 3727: ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
! 3728: ** ^Any attempt to create a function with a longer name
! 3729: ** will result in [SQLITE_MISUSE] being returned.
! 3730: **
! 3731: ** ^The third parameter (nArg)
! 3732: ** is the number of arguments that the SQL function or
! 3733: ** aggregate takes. ^If this parameter is -1, then the SQL function or
! 3734: ** aggregate may take any number of arguments between 0 and the limit
! 3735: ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
! 3736: ** parameter is less than -1 or greater than 127 then the behavior is
! 3737: ** undefined.
! 3738: **
! 3739: ** ^The fourth parameter, eTextRep, specifies what
! 3740: ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
! 3741: ** its parameters. Every SQL function implementation must be able to work
! 3742: ** with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
! 3743: ** more efficient with one encoding than another. ^An application may
! 3744: ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
! 3745: ** times with the same function but with different values of eTextRep.
! 3746: ** ^When multiple implementations of the same function are available, SQLite
! 3747: ** will pick the one that involves the least amount of data conversion.
! 3748: ** If there is only a single implementation which does not care what text
! 3749: ** encoding is used, then the fourth argument should be [SQLITE_ANY].
! 3750: **
! 3751: ** ^(The fifth parameter is an arbitrary pointer. The implementation of the
! 3752: ** function can gain access to this pointer using [sqlite3_user_data()].)^
! 3753: **
! 3754: ** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
! 3755: ** pointers to C-language functions that implement the SQL function or
! 3756: ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
! 3757: ** callback only; NULL pointers must be passed as the xStep and xFinal
! 3758: ** parameters. ^An aggregate SQL function requires an implementation of xStep
! 3759: ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
! 3760: ** SQL function or aggregate, pass NULL pointers for all three function
! 3761: ** callbacks.
! 3762: **
! 3763: ** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
! 3764: ** then it is destructor for the application data pointer.
! 3765: ** The destructor is invoked when the function is deleted, either by being
! 3766: ** overloaded or when the database connection closes.)^
! 3767: ** ^The destructor is also invoked if the call to
! 3768: ** sqlite3_create_function_v2() fails.
! 3769: ** ^When the destructor callback of the tenth parameter is invoked, it
! 3770: ** is passed a single argument which is a copy of the application data
! 3771: ** pointer which was the fifth parameter to sqlite3_create_function_v2().
! 3772: **
! 3773: ** ^It is permitted to register multiple implementations of the same
! 3774: ** functions with the same name but with either differing numbers of
! 3775: ** arguments or differing preferred text encodings. ^SQLite will use
! 3776: ** the implementation that most closely matches the way in which the
! 3777: ** SQL function is used. ^A function implementation with a non-negative
! 3778: ** nArg parameter is a better match than a function implementation with
! 3779: ** a negative nArg. ^A function where the preferred text encoding
! 3780: ** matches the database encoding is a better
! 3781: ** match than a function where the encoding is different.
! 3782: ** ^A function where the encoding difference is between UTF16le and UTF16be
! 3783: ** is a closer match than a function where the encoding difference is
! 3784: ** between UTF8 and UTF16.
! 3785: **
! 3786: ** ^Built-in functions may be overloaded by new application-defined functions.
! 3787: **
! 3788: ** ^An application-defined function is permitted to call other
! 3789: ** SQLite interfaces. However, such calls must not
! 3790: ** close the database connection nor finalize or reset the prepared
! 3791: ** statement in which the function is running.
! 3792: */
! 3793: int sqlite3_create_function(
! 3794: sqlite3 *db,
! 3795: const char *zFunctionName,
! 3796: int nArg,
! 3797: int eTextRep,
! 3798: void *pApp,
! 3799: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
! 3800: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
! 3801: void (*xFinal)(sqlite3_context*)
! 3802: );
! 3803: int sqlite3_create_function16(
! 3804: sqlite3 *db,
! 3805: const void *zFunctionName,
! 3806: int nArg,
! 3807: int eTextRep,
! 3808: void *pApp,
! 3809: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
! 3810: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
! 3811: void (*xFinal)(sqlite3_context*)
! 3812: );
! 3813: int sqlite3_create_function_v2(
! 3814: sqlite3 *db,
! 3815: const char *zFunctionName,
! 3816: int nArg,
! 3817: int eTextRep,
! 3818: void *pApp,
! 3819: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
! 3820: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
! 3821: void (*xFinal)(sqlite3_context*),
! 3822: void(*xDestroy)(void*)
! 3823: );
! 3824:
! 3825: /*
! 3826: ** CAPI3REF: Text Encodings
! 3827: **
! 3828: ** These constant define integer codes that represent the various
! 3829: ** text encodings supported by SQLite.
! 3830: */
! 3831: #define SQLITE_UTF8 1
! 3832: #define SQLITE_UTF16LE 2
! 3833: #define SQLITE_UTF16BE 3
! 3834: #define SQLITE_UTF16 4 /* Use native byte order */
! 3835: #define SQLITE_ANY 5 /* sqlite3_create_function only */
! 3836: #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
! 3837:
! 3838: /*
! 3839: ** CAPI3REF: Deprecated Functions
! 3840: ** DEPRECATED
! 3841: **
! 3842: ** These functions are [deprecated]. In order to maintain
! 3843: ** backwards compatibility with older code, these functions continue
! 3844: ** to be supported. However, new applications should avoid
! 3845: ** the use of these functions. To help encourage people to avoid
! 3846: ** using these functions, we are not going to tell you what they do.
! 3847: */
! 3848: #ifndef SQLITE_OMIT_DEPRECATED
! 3849: SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
! 3850: SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
! 3851: SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
! 3852: SQLITE_DEPRECATED int sqlite3_global_recover(void);
! 3853: SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
! 3854: SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
! 3855: #endif
! 3856:
! 3857: /*
! 3858: ** CAPI3REF: Obtaining SQL Function Parameter Values
! 3859: **
! 3860: ** The C-language implementation of SQL functions and aggregates uses
! 3861: ** this set of interface routines to access the parameter values on
! 3862: ** the function or aggregate.
! 3863: **
! 3864: ** The xFunc (for scalar functions) or xStep (for aggregates) parameters
! 3865: ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
! 3866: ** define callbacks that implement the SQL functions and aggregates.
! 3867: ** The 3rd parameter to these callbacks is an array of pointers to
! 3868: ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
! 3869: ** each parameter to the SQL function. These routines are used to
! 3870: ** extract values from the [sqlite3_value] objects.
! 3871: **
! 3872: ** These routines work only with [protected sqlite3_value] objects.
! 3873: ** Any attempt to use these routines on an [unprotected sqlite3_value]
! 3874: ** object results in undefined behavior.
! 3875: **
! 3876: ** ^These routines work just like the corresponding [column access functions]
! 3877: ** except that these routines take a single [protected sqlite3_value] object
! 3878: ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
! 3879: **
! 3880: ** ^The sqlite3_value_text16() interface extracts a UTF-16 string
! 3881: ** in the native byte-order of the host machine. ^The
! 3882: ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
! 3883: ** extract UTF-16 strings as big-endian and little-endian respectively.
! 3884: **
! 3885: ** ^(The sqlite3_value_numeric_type() interface attempts to apply
! 3886: ** numeric affinity to the value. This means that an attempt is
! 3887: ** made to convert the value to an integer or floating point. If
! 3888: ** such a conversion is possible without loss of information (in other
! 3889: ** words, if the value is a string that looks like a number)
! 3890: ** then the conversion is performed. Otherwise no conversion occurs.
! 3891: ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
! 3892: **
! 3893: ** Please pay particular attention to the fact that the pointer returned
! 3894: ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
! 3895: ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
! 3896: ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
! 3897: ** or [sqlite3_value_text16()].
! 3898: **
! 3899: ** These routines must be called from the same thread as
! 3900: ** the SQL function that supplied the [sqlite3_value*] parameters.
! 3901: */
! 3902: const void *sqlite3_value_blob(sqlite3_value*);
! 3903: int sqlite3_value_bytes(sqlite3_value*);
! 3904: int sqlite3_value_bytes16(sqlite3_value*);
! 3905: double sqlite3_value_double(sqlite3_value*);
! 3906: int sqlite3_value_int(sqlite3_value*);
! 3907: sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
! 3908: const unsigned char *sqlite3_value_text(sqlite3_value*);
! 3909: const void *sqlite3_value_text16(sqlite3_value*);
! 3910: const void *sqlite3_value_text16le(sqlite3_value*);
! 3911: const void *sqlite3_value_text16be(sqlite3_value*);
! 3912: int sqlite3_value_type(sqlite3_value*);
! 3913: int sqlite3_value_numeric_type(sqlite3_value*);
! 3914:
! 3915: /*
! 3916: ** CAPI3REF: Obtain Aggregate Function Context
! 3917: **
! 3918: ** Implementations of aggregate SQL functions use this
! 3919: ** routine to allocate memory for storing their state.
! 3920: **
! 3921: ** ^The first time the sqlite3_aggregate_context(C,N) routine is called
! 3922: ** for a particular aggregate function, SQLite
! 3923: ** allocates N of memory, zeroes out that memory, and returns a pointer
! 3924: ** to the new memory. ^On second and subsequent calls to
! 3925: ** sqlite3_aggregate_context() for the same aggregate function instance,
! 3926: ** the same buffer is returned. Sqlite3_aggregate_context() is normally
! 3927: ** called once for each invocation of the xStep callback and then one
! 3928: ** last time when the xFinal callback is invoked. ^(When no rows match
! 3929: ** an aggregate query, the xStep() callback of the aggregate function
! 3930: ** implementation is never called and xFinal() is called exactly once.
! 3931: ** In those cases, sqlite3_aggregate_context() might be called for the
! 3932: ** first time from within xFinal().)^
! 3933: **
! 3934: ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
! 3935: ** less than or equal to zero or if a memory allocate error occurs.
! 3936: **
! 3937: ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
! 3938: ** determined by the N parameter on first successful call. Changing the
! 3939: ** value of N in subsequent call to sqlite3_aggregate_context() within
! 3940: ** the same aggregate function instance will not resize the memory
! 3941: ** allocation.)^
! 3942: **
! 3943: ** ^SQLite automatically frees the memory allocated by
! 3944: ** sqlite3_aggregate_context() when the aggregate query concludes.
! 3945: **
! 3946: ** The first parameter must be a copy of the
! 3947: ** [sqlite3_context | SQL function context] that is the first parameter
! 3948: ** to the xStep or xFinal callback routine that implements the aggregate
! 3949: ** function.
! 3950: **
! 3951: ** This routine must be called from the same thread in which
! 3952: ** the aggregate SQL function is running.
! 3953: */
! 3954: void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
! 3955:
! 3956: /*
! 3957: ** CAPI3REF: User Data For Functions
! 3958: **
! 3959: ** ^The sqlite3_user_data() interface returns a copy of
! 3960: ** the pointer that was the pUserData parameter (the 5th parameter)
! 3961: ** of the [sqlite3_create_function()]
! 3962: ** and [sqlite3_create_function16()] routines that originally
! 3963: ** registered the application defined function.
! 3964: **
! 3965: ** This routine must be called from the same thread in which
! 3966: ** the application-defined function is running.
! 3967: */
! 3968: void *sqlite3_user_data(sqlite3_context*);
! 3969:
! 3970: /*
! 3971: ** CAPI3REF: Database Connection For Functions
! 3972: **
! 3973: ** ^The sqlite3_context_db_handle() interface returns a copy of
! 3974: ** the pointer to the [database connection] (the 1st parameter)
! 3975: ** of the [sqlite3_create_function()]
! 3976: ** and [sqlite3_create_function16()] routines that originally
! 3977: ** registered the application defined function.
! 3978: */
! 3979: sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
! 3980:
! 3981: /*
! 3982: ** CAPI3REF: Function Auxiliary Data
! 3983: **
! 3984: ** The following two functions may be used by scalar SQL functions to
! 3985: ** associate metadata with argument values. If the same value is passed to
! 3986: ** multiple invocations of the same SQL function during query execution, under
! 3987: ** some circumstances the associated metadata may be preserved. This may
! 3988: ** be used, for example, to add a regular-expression matching scalar
! 3989: ** function. The compiled version of the regular expression is stored as
! 3990: ** metadata associated with the SQL value passed as the regular expression
! 3991: ** pattern. The compiled regular expression can be reused on multiple
! 3992: ** invocations of the same function so that the original pattern string
! 3993: ** does not need to be recompiled on each invocation.
! 3994: **
! 3995: ** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
! 3996: ** associated by the sqlite3_set_auxdata() function with the Nth argument
! 3997: ** value to the application-defined function. ^If no metadata has been ever
! 3998: ** been set for the Nth argument of the function, or if the corresponding
! 3999: ** function parameter has changed since the meta-data was set,
! 4000: ** then sqlite3_get_auxdata() returns a NULL pointer.
! 4001: **
! 4002: ** ^The sqlite3_set_auxdata() interface saves the metadata
! 4003: ** pointed to by its 3rd parameter as the metadata for the N-th
! 4004: ** argument of the application-defined function. Subsequent
! 4005: ** calls to sqlite3_get_auxdata() might return this data, if it has
! 4006: ** not been destroyed.
! 4007: ** ^If it is not NULL, SQLite will invoke the destructor
! 4008: ** function given by the 4th parameter to sqlite3_set_auxdata() on
! 4009: ** the metadata when the corresponding function parameter changes
! 4010: ** or when the SQL statement completes, whichever comes first.
! 4011: **
! 4012: ** SQLite is free to call the destructor and drop metadata on any
! 4013: ** parameter of any function at any time. ^The only guarantee is that
! 4014: ** the destructor will be called before the metadata is dropped.
! 4015: **
! 4016: ** ^(In practice, metadata is preserved between function calls for
! 4017: ** expressions that are constant at compile time. This includes literal
! 4018: ** values and [parameters].)^
! 4019: **
! 4020: ** These routines must be called from the same thread in which
! 4021: ** the SQL function is running.
! 4022: */
! 4023: void *sqlite3_get_auxdata(sqlite3_context*, int N);
! 4024: void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
! 4025:
! 4026:
! 4027: /*
! 4028: ** CAPI3REF: Constants Defining Special Destructor Behavior
! 4029: **
! 4030: ** These are special values for the destructor that is passed in as the
! 4031: ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
! 4032: ** argument is SQLITE_STATIC, it means that the content pointer is constant
! 4033: ** and will never change. It does not need to be destroyed. ^The
! 4034: ** SQLITE_TRANSIENT value means that the content will likely change in
! 4035: ** the near future and that SQLite should make its own private copy of
! 4036: ** the content before returning.
! 4037: **
! 4038: ** The typedef is necessary to work around problems in certain
! 4039: ** C++ compilers. See ticket #2191.
! 4040: */
! 4041: typedef void (*sqlite3_destructor_type)(void*);
! 4042: #define SQLITE_STATIC ((sqlite3_destructor_type)0)
! 4043: #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
! 4044:
! 4045: /*
! 4046: ** CAPI3REF: Setting The Result Of An SQL Function
! 4047: **
! 4048: ** These routines are used by the xFunc or xFinal callbacks that
! 4049: ** implement SQL functions and aggregates. See
! 4050: ** [sqlite3_create_function()] and [sqlite3_create_function16()]
! 4051: ** for additional information.
! 4052: **
! 4053: ** These functions work very much like the [parameter binding] family of
! 4054: ** functions used to bind values to host parameters in prepared statements.
! 4055: ** Refer to the [SQL parameter] documentation for additional information.
! 4056: **
! 4057: ** ^The sqlite3_result_blob() interface sets the result from
! 4058: ** an application-defined function to be the BLOB whose content is pointed
! 4059: ** to by the second parameter and which is N bytes long where N is the
! 4060: ** third parameter.
! 4061: **
! 4062: ** ^The sqlite3_result_zeroblob() interfaces set the result of
! 4063: ** the application-defined function to be a BLOB containing all zero
! 4064: ** bytes and N bytes in size, where N is the value of the 2nd parameter.
! 4065: **
! 4066: ** ^The sqlite3_result_double() interface sets the result from
! 4067: ** an application-defined function to be a floating point value specified
! 4068: ** by its 2nd argument.
! 4069: **
! 4070: ** ^The sqlite3_result_error() and sqlite3_result_error16() functions
! 4071: ** cause the implemented SQL function to throw an exception.
! 4072: ** ^SQLite uses the string pointed to by the
! 4073: ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
! 4074: ** as the text of an error message. ^SQLite interprets the error
! 4075: ** message string from sqlite3_result_error() as UTF-8. ^SQLite
! 4076: ** interprets the string from sqlite3_result_error16() as UTF-16 in native
! 4077: ** byte order. ^If the third parameter to sqlite3_result_error()
! 4078: ** or sqlite3_result_error16() is negative then SQLite takes as the error
! 4079: ** message all text up through the first zero character.
! 4080: ** ^If the third parameter to sqlite3_result_error() or
! 4081: ** sqlite3_result_error16() is non-negative then SQLite takes that many
! 4082: ** bytes (not characters) from the 2nd parameter as the error message.
! 4083: ** ^The sqlite3_result_error() and sqlite3_result_error16()
! 4084: ** routines make a private copy of the error message text before
! 4085: ** they return. Hence, the calling function can deallocate or
! 4086: ** modify the text after they return without harm.
! 4087: ** ^The sqlite3_result_error_code() function changes the error code
! 4088: ** returned by SQLite as a result of an error in a function. ^By default,
! 4089: ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
! 4090: ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
! 4091: **
! 4092: ** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
! 4093: ** indicating that a string or BLOB is too long to represent.
! 4094: **
! 4095: ** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
! 4096: ** indicating that a memory allocation failed.
! 4097: **
! 4098: ** ^The sqlite3_result_int() interface sets the return value
! 4099: ** of the application-defined function to be the 32-bit signed integer
! 4100: ** value given in the 2nd argument.
! 4101: ** ^The sqlite3_result_int64() interface sets the return value
! 4102: ** of the application-defined function to be the 64-bit signed integer
! 4103: ** value given in the 2nd argument.
! 4104: **
! 4105: ** ^The sqlite3_result_null() interface sets the return value
! 4106: ** of the application-defined function to be NULL.
! 4107: **
! 4108: ** ^The sqlite3_result_text(), sqlite3_result_text16(),
! 4109: ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
! 4110: ** set the return value of the application-defined function to be
! 4111: ** a text string which is represented as UTF-8, UTF-16 native byte order,
! 4112: ** UTF-16 little endian, or UTF-16 big endian, respectively.
! 4113: ** ^SQLite takes the text result from the application from
! 4114: ** the 2nd parameter of the sqlite3_result_text* interfaces.
! 4115: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
! 4116: ** is negative, then SQLite takes result text from the 2nd parameter
! 4117: ** through the first zero character.
! 4118: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
! 4119: ** is non-negative, then as many bytes (not characters) of the text
! 4120: ** pointed to by the 2nd parameter are taken as the application-defined
! 4121: ** function result. If the 3rd parameter is non-negative, then it
! 4122: ** must be the byte offset into the string where the NUL terminator would
! 4123: ** appear if the string where NUL terminated. If any NUL characters occur
! 4124: ** in the string at a byte offset that is less than the value of the 3rd
! 4125: ** parameter, then the resulting string will contain embedded NULs and the
! 4126: ** result of expressions operating on strings with embedded NULs is undefined.
! 4127: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
! 4128: ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
! 4129: ** function as the destructor on the text or BLOB result when it has
! 4130: ** finished using that result.
! 4131: ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
! 4132: ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
! 4133: ** assumes that the text or BLOB result is in constant space and does not
! 4134: ** copy the content of the parameter nor call a destructor on the content
! 4135: ** when it has finished using that result.
! 4136: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
! 4137: ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
! 4138: ** then SQLite makes a copy of the result into space obtained from
! 4139: ** from [sqlite3_malloc()] before it returns.
! 4140: **
! 4141: ** ^The sqlite3_result_value() interface sets the result of
! 4142: ** the application-defined function to be a copy the
! 4143: ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
! 4144: ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
! 4145: ** so that the [sqlite3_value] specified in the parameter may change or
! 4146: ** be deallocated after sqlite3_result_value() returns without harm.
! 4147: ** ^A [protected sqlite3_value] object may always be used where an
! 4148: ** [unprotected sqlite3_value] object is required, so either
! 4149: ** kind of [sqlite3_value] object can be used with this interface.
! 4150: **
! 4151: ** If these routines are called from within the different thread
! 4152: ** than the one containing the application-defined function that received
! 4153: ** the [sqlite3_context] pointer, the results are undefined.
! 4154: */
! 4155: void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
! 4156: void sqlite3_result_double(sqlite3_context*, double);
! 4157: void sqlite3_result_error(sqlite3_context*, const char*, int);
! 4158: void sqlite3_result_error16(sqlite3_context*, const void*, int);
! 4159: void sqlite3_result_error_toobig(sqlite3_context*);
! 4160: void sqlite3_result_error_nomem(sqlite3_context*);
! 4161: void sqlite3_result_error_code(sqlite3_context*, int);
! 4162: void sqlite3_result_int(sqlite3_context*, int);
! 4163: void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
! 4164: void sqlite3_result_null(sqlite3_context*);
! 4165: void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
! 4166: void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
! 4167: void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
! 4168: void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
! 4169: void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
! 4170: void sqlite3_result_zeroblob(sqlite3_context*, int n);
! 4171:
! 4172: /*
! 4173: ** CAPI3REF: Define New Collating Sequences
! 4174: **
! 4175: ** ^These functions add, remove, or modify a [collation] associated
! 4176: ** with the [database connection] specified as the first argument.
! 4177: **
! 4178: ** ^The name of the collation is a UTF-8 string
! 4179: ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
! 4180: ** and a UTF-16 string in native byte order for sqlite3_create_collation16().
! 4181: ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
! 4182: ** considered to be the same name.
! 4183: **
! 4184: ** ^(The third argument (eTextRep) must be one of the constants:
! 4185: ** <ul>
! 4186: ** <li> [SQLITE_UTF8],
! 4187: ** <li> [SQLITE_UTF16LE],
! 4188: ** <li> [SQLITE_UTF16BE],
! 4189: ** <li> [SQLITE_UTF16], or
! 4190: ** <li> [SQLITE_UTF16_ALIGNED].
! 4191: ** </ul>)^
! 4192: ** ^The eTextRep argument determines the encoding of strings passed
! 4193: ** to the collating function callback, xCallback.
! 4194: ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
! 4195: ** force strings to be UTF16 with native byte order.
! 4196: ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
! 4197: ** on an even byte address.
! 4198: **
! 4199: ** ^The fourth argument, pArg, is an application data pointer that is passed
! 4200: ** through as the first argument to the collating function callback.
! 4201: **
! 4202: ** ^The fifth argument, xCallback, is a pointer to the collating function.
! 4203: ** ^Multiple collating functions can be registered using the same name but
! 4204: ** with different eTextRep parameters and SQLite will use whichever
! 4205: ** function requires the least amount of data transformation.
! 4206: ** ^If the xCallback argument is NULL then the collating function is
! 4207: ** deleted. ^When all collating functions having the same name are deleted,
! 4208: ** that collation is no longer usable.
! 4209: **
! 4210: ** ^The collating function callback is invoked with a copy of the pArg
! 4211: ** application data pointer and with two strings in the encoding specified
! 4212: ** by the eTextRep argument. The collating function must return an
! 4213: ** integer that is negative, zero, or positive
! 4214: ** if the first string is less than, equal to, or greater than the second,
! 4215: ** respectively. A collating function must always return the same answer
! 4216: ** given the same inputs. If two or more collating functions are registered
! 4217: ** to the same collation name (using different eTextRep values) then all
! 4218: ** must give an equivalent answer when invoked with equivalent strings.
! 4219: ** The collating function must obey the following properties for all
! 4220: ** strings A, B, and C:
! 4221: **
! 4222: ** <ol>
! 4223: ** <li> If A==B then B==A.
! 4224: ** <li> If A==B and B==C then A==C.
! 4225: ** <li> If A<B THEN B>A.
! 4226: ** <li> If A<B and B<C then A<C.
! 4227: ** </ol>
! 4228: **
! 4229: ** If a collating function fails any of the above constraints and that
! 4230: ** collating function is registered and used, then the behavior of SQLite
! 4231: ** is undefined.
! 4232: **
! 4233: ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
! 4234: ** with the addition that the xDestroy callback is invoked on pArg when
! 4235: ** the collating function is deleted.
! 4236: ** ^Collating functions are deleted when they are overridden by later
! 4237: ** calls to the collation creation functions or when the
! 4238: ** [database connection] is closed using [sqlite3_close()].
! 4239: **
! 4240: ** ^The xDestroy callback is <u>not</u> called if the
! 4241: ** sqlite3_create_collation_v2() function fails. Applications that invoke
! 4242: ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
! 4243: ** check the return code and dispose of the application data pointer
! 4244: ** themselves rather than expecting SQLite to deal with it for them.
! 4245: ** This is different from every other SQLite interface. The inconsistency
! 4246: ** is unfortunate but cannot be changed without breaking backwards
! 4247: ** compatibility.
! 4248: **
! 4249: ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
! 4250: */
! 4251: int sqlite3_create_collation(
! 4252: sqlite3*,
! 4253: const char *zName,
! 4254: int eTextRep,
! 4255: void *pArg,
! 4256: int(*xCompare)(void*,int,const void*,int,const void*)
! 4257: );
! 4258: int sqlite3_create_collation_v2(
! 4259: sqlite3*,
! 4260: const char *zName,
! 4261: int eTextRep,
! 4262: void *pArg,
! 4263: int(*xCompare)(void*,int,const void*,int,const void*),
! 4264: void(*xDestroy)(void*)
! 4265: );
! 4266: int sqlite3_create_collation16(
! 4267: sqlite3*,
! 4268: const void *zName,
! 4269: int eTextRep,
! 4270: void *pArg,
! 4271: int(*xCompare)(void*,int,const void*,int,const void*)
! 4272: );
! 4273:
! 4274: /*
! 4275: ** CAPI3REF: Collation Needed Callbacks
! 4276: **
! 4277: ** ^To avoid having to register all collation sequences before a database
! 4278: ** can be used, a single callback function may be registered with the
! 4279: ** [database connection] to be invoked whenever an undefined collation
! 4280: ** sequence is required.
! 4281: **
! 4282: ** ^If the function is registered using the sqlite3_collation_needed() API,
! 4283: ** then it is passed the names of undefined collation sequences as strings
! 4284: ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
! 4285: ** the names are passed as UTF-16 in machine native byte order.
! 4286: ** ^A call to either function replaces the existing collation-needed callback.
! 4287: **
! 4288: ** ^(When the callback is invoked, the first argument passed is a copy
! 4289: ** of the second argument to sqlite3_collation_needed() or
! 4290: ** sqlite3_collation_needed16(). The second argument is the database
! 4291: ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
! 4292: ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
! 4293: ** sequence function required. The fourth parameter is the name of the
! 4294: ** required collation sequence.)^
! 4295: **
! 4296: ** The callback function should register the desired collation using
! 4297: ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
! 4298: ** [sqlite3_create_collation_v2()].
! 4299: */
! 4300: int sqlite3_collation_needed(
! 4301: sqlite3*,
! 4302: void*,
! 4303: void(*)(void*,sqlite3*,int eTextRep,const char*)
! 4304: );
! 4305: int sqlite3_collation_needed16(
! 4306: sqlite3*,
! 4307: void*,
! 4308: void(*)(void*,sqlite3*,int eTextRep,const void*)
! 4309: );
! 4310:
! 4311: #ifdef SQLITE_HAS_CODEC
! 4312: /*
! 4313: ** Specify the key for an encrypted database. This routine should be
! 4314: ** called right after sqlite3_open().
! 4315: **
! 4316: ** The code to implement this API is not available in the public release
! 4317: ** of SQLite.
! 4318: */
! 4319: int sqlite3_key(
! 4320: sqlite3 *db, /* Database to be rekeyed */
! 4321: const void *pKey, int nKey /* The key */
! 4322: );
! 4323:
! 4324: /*
! 4325: ** Change the key on an open database. If the current database is not
! 4326: ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
! 4327: ** database is decrypted.
! 4328: **
! 4329: ** The code to implement this API is not available in the public release
! 4330: ** of SQLite.
! 4331: */
! 4332: int sqlite3_rekey(
! 4333: sqlite3 *db, /* Database to be rekeyed */
! 4334: const void *pKey, int nKey /* The new key */
! 4335: );
! 4336:
! 4337: /*
! 4338: ** Specify the activation key for a SEE database. Unless
! 4339: ** activated, none of the SEE routines will work.
! 4340: */
! 4341: void sqlite3_activate_see(
! 4342: const char *zPassPhrase /* Activation phrase */
! 4343: );
! 4344: #endif
! 4345:
! 4346: #ifdef SQLITE_ENABLE_CEROD
! 4347: /*
! 4348: ** Specify the activation key for a CEROD database. Unless
! 4349: ** activated, none of the CEROD routines will work.
! 4350: */
! 4351: void sqlite3_activate_cerod(
! 4352: const char *zPassPhrase /* Activation phrase */
! 4353: );
! 4354: #endif
! 4355:
! 4356: /*
! 4357: ** CAPI3REF: Suspend Execution For A Short Time
! 4358: **
! 4359: ** The sqlite3_sleep() function causes the current thread to suspend execution
! 4360: ** for at least a number of milliseconds specified in its parameter.
! 4361: **
! 4362: ** If the operating system does not support sleep requests with
! 4363: ** millisecond time resolution, then the time will be rounded up to
! 4364: ** the nearest second. The number of milliseconds of sleep actually
! 4365: ** requested from the operating system is returned.
! 4366: **
! 4367: ** ^SQLite implements this interface by calling the xSleep()
! 4368: ** method of the default [sqlite3_vfs] object. If the xSleep() method
! 4369: ** of the default VFS is not implemented correctly, or not implemented at
! 4370: ** all, then the behavior of sqlite3_sleep() may deviate from the description
! 4371: ** in the previous paragraphs.
! 4372: */
! 4373: int sqlite3_sleep(int);
! 4374:
! 4375: /*
! 4376: ** CAPI3REF: Name Of The Folder Holding Temporary Files
! 4377: **
! 4378: ** ^(If this global variable is made to point to a string which is
! 4379: ** the name of a folder (a.k.a. directory), then all temporary files
! 4380: ** created by SQLite when using a built-in [sqlite3_vfs | VFS]
! 4381: ** will be placed in that directory.)^ ^If this variable
! 4382: ** is a NULL pointer, then SQLite performs a search for an appropriate
! 4383: ** temporary file directory.
! 4384: **
! 4385: ** It is not safe to read or modify this variable in more than one
! 4386: ** thread at a time. It is not safe to read or modify this variable
! 4387: ** if a [database connection] is being used at the same time in a separate
! 4388: ** thread.
! 4389: ** It is intended that this variable be set once
! 4390: ** as part of process initialization and before any SQLite interface
! 4391: ** routines have been called and that this variable remain unchanged
! 4392: ** thereafter.
! 4393: **
! 4394: ** ^The [temp_store_directory pragma] may modify this variable and cause
! 4395: ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
! 4396: ** the [temp_store_directory pragma] always assumes that any string
! 4397: ** that this variable points to is held in memory obtained from
! 4398: ** [sqlite3_malloc] and the pragma may attempt to free that memory
! 4399: ** using [sqlite3_free].
! 4400: ** Hence, if this variable is modified directly, either it should be
! 4401: ** made NULL or made to point to memory obtained from [sqlite3_malloc]
! 4402: ** or else the use of the [temp_store_directory pragma] should be avoided.
! 4403: */
! 4404: SQLITE_EXTERN char *sqlite3_temp_directory;
! 4405:
! 4406: /*
! 4407: ** CAPI3REF: Test For Auto-Commit Mode
! 4408: ** KEYWORDS: {autocommit mode}
! 4409: **
! 4410: ** ^The sqlite3_get_autocommit() interface returns non-zero or
! 4411: ** zero if the given database connection is or is not in autocommit mode,
! 4412: ** respectively. ^Autocommit mode is on by default.
! 4413: ** ^Autocommit mode is disabled by a [BEGIN] statement.
! 4414: ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
! 4415: **
! 4416: ** If certain kinds of errors occur on a statement within a multi-statement
! 4417: ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
! 4418: ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
! 4419: ** transaction might be rolled back automatically. The only way to
! 4420: ** find out whether SQLite automatically rolled back the transaction after
! 4421: ** an error is to use this function.
! 4422: **
! 4423: ** If another thread changes the autocommit status of the database
! 4424: ** connection while this routine is running, then the return value
! 4425: ** is undefined.
! 4426: */
! 4427: int sqlite3_get_autocommit(sqlite3*);
! 4428:
! 4429: /*
! 4430: ** CAPI3REF: Find The Database Handle Of A Prepared Statement
! 4431: **
! 4432: ** ^The sqlite3_db_handle interface returns the [database connection] handle
! 4433: ** to which a [prepared statement] belongs. ^The [database connection]
! 4434: ** returned by sqlite3_db_handle is the same [database connection]
! 4435: ** that was the first argument
! 4436: ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
! 4437: ** create the statement in the first place.
! 4438: */
! 4439: sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
! 4440:
! 4441: /*
! 4442: ** CAPI3REF: Return The Filename For A Database Connection
! 4443: **
! 4444: ** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
! 4445: ** associated with database N of connection D. ^The main database file
! 4446: ** has the name "main". If there is no attached database N on the database
! 4447: ** connection D, or if database N is a temporary or in-memory database, then
! 4448: ** a NULL pointer is returned.
! 4449: **
! 4450: ** ^The filename returned by this function is the output of the
! 4451: ** xFullPathname method of the [VFS]. ^In other words, the filename
! 4452: ** will be an absolute pathname, even if the filename used
! 4453: ** to open the database originally was a URI or relative pathname.
! 4454: */
! 4455: const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
! 4456:
! 4457: /*
! 4458: ** CAPI3REF: Find the next prepared statement
! 4459: **
! 4460: ** ^This interface returns a pointer to the next [prepared statement] after
! 4461: ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
! 4462: ** then this interface returns a pointer to the first prepared statement
! 4463: ** associated with the database connection pDb. ^If no prepared statement
! 4464: ** satisfies the conditions of this routine, it returns NULL.
! 4465: **
! 4466: ** The [database connection] pointer D in a call to
! 4467: ** [sqlite3_next_stmt(D,S)] must refer to an open database
! 4468: ** connection and in particular must not be a NULL pointer.
! 4469: */
! 4470: sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
! 4471:
! 4472: /*
! 4473: ** CAPI3REF: Commit And Rollback Notification Callbacks
! 4474: **
! 4475: ** ^The sqlite3_commit_hook() interface registers a callback
! 4476: ** function to be invoked whenever a transaction is [COMMIT | committed].
! 4477: ** ^Any callback set by a previous call to sqlite3_commit_hook()
! 4478: ** for the same database connection is overridden.
! 4479: ** ^The sqlite3_rollback_hook() interface registers a callback
! 4480: ** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
! 4481: ** ^Any callback set by a previous call to sqlite3_rollback_hook()
! 4482: ** for the same database connection is overridden.
! 4483: ** ^The pArg argument is passed through to the callback.
! 4484: ** ^If the callback on a commit hook function returns non-zero,
! 4485: ** then the commit is converted into a rollback.
! 4486: **
! 4487: ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
! 4488: ** return the P argument from the previous call of the same function
! 4489: ** on the same [database connection] D, or NULL for
! 4490: ** the first call for each function on D.
! 4491: **
! 4492: ** The commit and rollback hook callbacks are not reentrant.
! 4493: ** The callback implementation must not do anything that will modify
! 4494: ** the database connection that invoked the callback. Any actions
! 4495: ** to modify the database connection must be deferred until after the
! 4496: ** completion of the [sqlite3_step()] call that triggered the commit
! 4497: ** or rollback hook in the first place.
! 4498: ** Note that running any other SQL statements, including SELECT statements,
! 4499: ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
! 4500: ** the database connections for the meaning of "modify" in this paragraph.
! 4501: **
! 4502: ** ^Registering a NULL function disables the callback.
! 4503: **
! 4504: ** ^When the commit hook callback routine returns zero, the [COMMIT]
! 4505: ** operation is allowed to continue normally. ^If the commit hook
! 4506: ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
! 4507: ** ^The rollback hook is invoked on a rollback that results from a commit
! 4508: ** hook returning non-zero, just as it would be with any other rollback.
! 4509: **
! 4510: ** ^For the purposes of this API, a transaction is said to have been
! 4511: ** rolled back if an explicit "ROLLBACK" statement is executed, or
! 4512: ** an error or constraint causes an implicit rollback to occur.
! 4513: ** ^The rollback callback is not invoked if a transaction is
! 4514: ** automatically rolled back because the database connection is closed.
! 4515: **
! 4516: ** See also the [sqlite3_update_hook()] interface.
! 4517: */
! 4518: void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
! 4519: void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
! 4520:
! 4521: /*
! 4522: ** CAPI3REF: Data Change Notification Callbacks
! 4523: **
! 4524: ** ^The sqlite3_update_hook() interface registers a callback function
! 4525: ** with the [database connection] identified by the first argument
! 4526: ** to be invoked whenever a row is updated, inserted or deleted.
! 4527: ** ^Any callback set by a previous call to this function
! 4528: ** for the same database connection is overridden.
! 4529: **
! 4530: ** ^The second argument is a pointer to the function to invoke when a
! 4531: ** row is updated, inserted or deleted.
! 4532: ** ^The first argument to the callback is a copy of the third argument
! 4533: ** to sqlite3_update_hook().
! 4534: ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
! 4535: ** or [SQLITE_UPDATE], depending on the operation that caused the callback
! 4536: ** to be invoked.
! 4537: ** ^The third and fourth arguments to the callback contain pointers to the
! 4538: ** database and table name containing the affected row.
! 4539: ** ^The final callback parameter is the [rowid] of the row.
! 4540: ** ^In the case of an update, this is the [rowid] after the update takes place.
! 4541: **
! 4542: ** ^(The update hook is not invoked when internal system tables are
! 4543: ** modified (i.e. sqlite_master and sqlite_sequence).)^
! 4544: **
! 4545: ** ^In the current implementation, the update hook
! 4546: ** is not invoked when duplication rows are deleted because of an
! 4547: ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
! 4548: ** invoked when rows are deleted using the [truncate optimization].
! 4549: ** The exceptions defined in this paragraph might change in a future
! 4550: ** release of SQLite.
! 4551: **
! 4552: ** The update hook implementation must not do anything that will modify
! 4553: ** the database connection that invoked the update hook. Any actions
! 4554: ** to modify the database connection must be deferred until after the
! 4555: ** completion of the [sqlite3_step()] call that triggered the update hook.
! 4556: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
! 4557: ** database connections for the meaning of "modify" in this paragraph.
! 4558: **
! 4559: ** ^The sqlite3_update_hook(D,C,P) function
! 4560: ** returns the P argument from the previous call
! 4561: ** on the same [database connection] D, or NULL for
! 4562: ** the first call on D.
! 4563: **
! 4564: ** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
! 4565: ** interfaces.
! 4566: */
! 4567: void *sqlite3_update_hook(
! 4568: sqlite3*,
! 4569: void(*)(void *,int ,char const *,char const *,sqlite3_int64),
! 4570: void*
! 4571: );
! 4572:
! 4573: /*
! 4574: ** CAPI3REF: Enable Or Disable Shared Pager Cache
! 4575: ** KEYWORDS: {shared cache}
! 4576: **
! 4577: ** ^(This routine enables or disables the sharing of the database cache
! 4578: ** and schema data structures between [database connection | connections]
! 4579: ** to the same database. Sharing is enabled if the argument is true
! 4580: ** and disabled if the argument is false.)^
! 4581: **
! 4582: ** ^Cache sharing is enabled and disabled for an entire process.
! 4583: ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
! 4584: ** sharing was enabled or disabled for each thread separately.
! 4585: **
! 4586: ** ^(The cache sharing mode set by this interface effects all subsequent
! 4587: ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
! 4588: ** Existing database connections continue use the sharing mode
! 4589: ** that was in effect at the time they were opened.)^
! 4590: **
! 4591: ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
! 4592: ** successfully. An [error code] is returned otherwise.)^
! 4593: **
! 4594: ** ^Shared cache is disabled by default. But this might change in
! 4595: ** future releases of SQLite. Applications that care about shared
! 4596: ** cache setting should set it explicitly.
! 4597: **
! 4598: ** See Also: [SQLite Shared-Cache Mode]
! 4599: */
! 4600: int sqlite3_enable_shared_cache(int);
! 4601:
! 4602: /*
! 4603: ** CAPI3REF: Attempt To Free Heap Memory
! 4604: **
! 4605: ** ^The sqlite3_release_memory() interface attempts to free N bytes
! 4606: ** of heap memory by deallocating non-essential memory allocations
! 4607: ** held by the database library. Memory used to cache database
! 4608: ** pages to improve performance is an example of non-essential memory.
! 4609: ** ^sqlite3_release_memory() returns the number of bytes actually freed,
! 4610: ** which might be more or less than the amount requested.
! 4611: ** ^The sqlite3_release_memory() routine is a no-op returning zero
! 4612: ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
! 4613: **
! 4614: ** See also: [sqlite3_db_release_memory()]
! 4615: */
! 4616: int sqlite3_release_memory(int);
! 4617:
! 4618: /*
! 4619: ** CAPI3REF: Free Memory Used By A Database Connection
! 4620: **
! 4621: ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
! 4622: ** memory as possible from database connection D. Unlike the
! 4623: ** [sqlite3_release_memory()] interface, this interface is effect even
! 4624: ** when then [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
! 4625: ** omitted.
! 4626: **
! 4627: ** See also: [sqlite3_release_memory()]
! 4628: */
! 4629: int sqlite3_db_release_memory(sqlite3*);
! 4630:
! 4631: /*
! 4632: ** CAPI3REF: Impose A Limit On Heap Size
! 4633: **
! 4634: ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
! 4635: ** soft limit on the amount of heap memory that may be allocated by SQLite.
! 4636: ** ^SQLite strives to keep heap memory utilization below the soft heap
! 4637: ** limit by reducing the number of pages held in the page cache
! 4638: ** as heap memory usages approaches the limit.
! 4639: ** ^The soft heap limit is "soft" because even though SQLite strives to stay
! 4640: ** below the limit, it will exceed the limit rather than generate
! 4641: ** an [SQLITE_NOMEM] error. In other words, the soft heap limit
! 4642: ** is advisory only.
! 4643: **
! 4644: ** ^The return value from sqlite3_soft_heap_limit64() is the size of
! 4645: ** the soft heap limit prior to the call, or negative in the case of an
! 4646: ** error. ^If the argument N is negative
! 4647: ** then no change is made to the soft heap limit. Hence, the current
! 4648: ** size of the soft heap limit can be determined by invoking
! 4649: ** sqlite3_soft_heap_limit64() with a negative argument.
! 4650: **
! 4651: ** ^If the argument N is zero then the soft heap limit is disabled.
! 4652: **
! 4653: ** ^(The soft heap limit is not enforced in the current implementation
! 4654: ** if one or more of following conditions are true:
! 4655: **
! 4656: ** <ul>
! 4657: ** <li> The soft heap limit is set to zero.
! 4658: ** <li> Memory accounting is disabled using a combination of the
! 4659: ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
! 4660: ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
! 4661: ** <li> An alternative page cache implementation is specified using
! 4662: ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
! 4663: ** <li> The page cache allocates from its own memory pool supplied
! 4664: ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
! 4665: ** from the heap.
! 4666: ** </ul>)^
! 4667: **
! 4668: ** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
! 4669: ** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
! 4670: ** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
! 4671: ** the soft heap limit is enforced on every memory allocation. Without
! 4672: ** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
! 4673: ** when memory is allocated by the page cache. Testing suggests that because
! 4674: ** the page cache is the predominate memory user in SQLite, most
! 4675: ** applications will achieve adequate soft heap limit enforcement without
! 4676: ** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
! 4677: **
! 4678: ** The circumstances under which SQLite will enforce the soft heap limit may
! 4679: ** changes in future releases of SQLite.
! 4680: */
! 4681: sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
! 4682:
! 4683: /*
! 4684: ** CAPI3REF: Deprecated Soft Heap Limit Interface
! 4685: ** DEPRECATED
! 4686: **
! 4687: ** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
! 4688: ** interface. This routine is provided for historical compatibility
! 4689: ** only. All new applications should use the
! 4690: ** [sqlite3_soft_heap_limit64()] interface rather than this one.
! 4691: */
! 4692: SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
! 4693:
! 4694:
! 4695: /*
! 4696: ** CAPI3REF: Extract Metadata About A Column Of A Table
! 4697: **
! 4698: ** ^This routine returns metadata about a specific column of a specific
! 4699: ** database table accessible using the [database connection] handle
! 4700: ** passed as the first function argument.
! 4701: **
! 4702: ** ^The column is identified by the second, third and fourth parameters to
! 4703: ** this function. ^The second parameter is either the name of the database
! 4704: ** (i.e. "main", "temp", or an attached database) containing the specified
! 4705: ** table or NULL. ^If it is NULL, then all attached databases are searched
! 4706: ** for the table using the same algorithm used by the database engine to
! 4707: ** resolve unqualified table references.
! 4708: **
! 4709: ** ^The third and fourth parameters to this function are the table and column
! 4710: ** name of the desired column, respectively. Neither of these parameters
! 4711: ** may be NULL.
! 4712: **
! 4713: ** ^Metadata is returned by writing to the memory locations passed as the 5th
! 4714: ** and subsequent parameters to this function. ^Any of these arguments may be
! 4715: ** NULL, in which case the corresponding element of metadata is omitted.
! 4716: **
! 4717: ** ^(<blockquote>
! 4718: ** <table border="1">
! 4719: ** <tr><th> Parameter <th> Output<br>Type <th> Description
! 4720: **
! 4721: ** <tr><td> 5th <td> const char* <td> Data type
! 4722: ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
! 4723: ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
! 4724: ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
! 4725: ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
! 4726: ** </table>
! 4727: ** </blockquote>)^
! 4728: **
! 4729: ** ^The memory pointed to by the character pointers returned for the
! 4730: ** declaration type and collation sequence is valid only until the next
! 4731: ** call to any SQLite API function.
! 4732: **
! 4733: ** ^If the specified table is actually a view, an [error code] is returned.
! 4734: **
! 4735: ** ^If the specified column is "rowid", "oid" or "_rowid_" and an
! 4736: ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
! 4737: ** parameters are set for the explicitly declared column. ^(If there is no
! 4738: ** explicitly declared [INTEGER PRIMARY KEY] column, then the output
! 4739: ** parameters are set as follows:
! 4740: **
! 4741: ** <pre>
! 4742: ** data type: "INTEGER"
! 4743: ** collation sequence: "BINARY"
! 4744: ** not null: 0
! 4745: ** primary key: 1
! 4746: ** auto increment: 0
! 4747: ** </pre>)^
! 4748: **
! 4749: ** ^(This function may load one or more schemas from database files. If an
! 4750: ** error occurs during this process, or if the requested table or column
! 4751: ** cannot be found, an [error code] is returned and an error message left
! 4752: ** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
! 4753: **
! 4754: ** ^This API is only available if the library was compiled with the
! 4755: ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
! 4756: */
! 4757: int sqlite3_table_column_metadata(
! 4758: sqlite3 *db, /* Connection handle */
! 4759: const char *zDbName, /* Database name or NULL */
! 4760: const char *zTableName, /* Table name */
! 4761: const char *zColumnName, /* Column name */
! 4762: char const **pzDataType, /* OUTPUT: Declared data type */
! 4763: char const **pzCollSeq, /* OUTPUT: Collation sequence name */
! 4764: int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
! 4765: int *pPrimaryKey, /* OUTPUT: True if column part of PK */
! 4766: int *pAutoinc /* OUTPUT: True if column is auto-increment */
! 4767: );
! 4768:
! 4769: /*
! 4770: ** CAPI3REF: Load An Extension
! 4771: **
! 4772: ** ^This interface loads an SQLite extension library from the named file.
! 4773: **
! 4774: ** ^The sqlite3_load_extension() interface attempts to load an
! 4775: ** SQLite extension library contained in the file zFile.
! 4776: **
! 4777: ** ^The entry point is zProc.
! 4778: ** ^zProc may be 0, in which case the name of the entry point
! 4779: ** defaults to "sqlite3_extension_init".
! 4780: ** ^The sqlite3_load_extension() interface returns
! 4781: ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
! 4782: ** ^If an error occurs and pzErrMsg is not 0, then the
! 4783: ** [sqlite3_load_extension()] interface shall attempt to
! 4784: ** fill *pzErrMsg with error message text stored in memory
! 4785: ** obtained from [sqlite3_malloc()]. The calling function
! 4786: ** should free this memory by calling [sqlite3_free()].
! 4787: **
! 4788: ** ^Extension loading must be enabled using
! 4789: ** [sqlite3_enable_load_extension()] prior to calling this API,
! 4790: ** otherwise an error will be returned.
! 4791: **
! 4792: ** See also the [load_extension() SQL function].
! 4793: */
! 4794: int sqlite3_load_extension(
! 4795: sqlite3 *db, /* Load the extension into this database connection */
! 4796: const char *zFile, /* Name of the shared library containing extension */
! 4797: const char *zProc, /* Entry point. Derived from zFile if 0 */
! 4798: char **pzErrMsg /* Put error message here if not 0 */
! 4799: );
! 4800:
! 4801: /*
! 4802: ** CAPI3REF: Enable Or Disable Extension Loading
! 4803: **
! 4804: ** ^So as not to open security holes in older applications that are
! 4805: ** unprepared to deal with extension loading, and as a means of disabling
! 4806: ** extension loading while evaluating user-entered SQL, the following API
! 4807: ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
! 4808: **
! 4809: ** ^Extension loading is off by default. See ticket #1863.
! 4810: ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
! 4811: ** to turn extension loading on and call it with onoff==0 to turn
! 4812: ** it back off again.
! 4813: */
! 4814: int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
! 4815:
! 4816: /*
! 4817: ** CAPI3REF: Automatically Load Statically Linked Extensions
! 4818: **
! 4819: ** ^This interface causes the xEntryPoint() function to be invoked for
! 4820: ** each new [database connection] that is created. The idea here is that
! 4821: ** xEntryPoint() is the entry point for a statically linked SQLite extension
! 4822: ** that is to be automatically loaded into all new database connections.
! 4823: **
! 4824: ** ^(Even though the function prototype shows that xEntryPoint() takes
! 4825: ** no arguments and returns void, SQLite invokes xEntryPoint() with three
! 4826: ** arguments and expects and integer result as if the signature of the
! 4827: ** entry point where as follows:
! 4828: **
! 4829: ** <blockquote><pre>
! 4830: ** int xEntryPoint(
! 4831: ** sqlite3 *db,
! 4832: ** const char **pzErrMsg,
! 4833: ** const struct sqlite3_api_routines *pThunk
! 4834: ** );
! 4835: ** </pre></blockquote>)^
! 4836: **
! 4837: ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
! 4838: ** point to an appropriate error message (obtained from [sqlite3_mprintf()])
! 4839: ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
! 4840: ** is NULL before calling the xEntryPoint(). ^SQLite will invoke
! 4841: ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
! 4842: ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
! 4843: ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
! 4844: **
! 4845: ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
! 4846: ** on the list of automatic extensions is a harmless no-op. ^No entry point
! 4847: ** will be called more than once for each database connection that is opened.
! 4848: **
! 4849: ** See also: [sqlite3_reset_auto_extension()].
! 4850: */
! 4851: int sqlite3_auto_extension(void (*xEntryPoint)(void));
! 4852:
! 4853: /*
! 4854: ** CAPI3REF: Reset Automatic Extension Loading
! 4855: **
! 4856: ** ^This interface disables all automatic extensions previously
! 4857: ** registered using [sqlite3_auto_extension()].
! 4858: */
! 4859: void sqlite3_reset_auto_extension(void);
! 4860:
! 4861: /*
! 4862: ** The interface to the virtual-table mechanism is currently considered
! 4863: ** to be experimental. The interface might change in incompatible ways.
! 4864: ** If this is a problem for you, do not use the interface at this time.
! 4865: **
! 4866: ** When the virtual-table mechanism stabilizes, we will declare the
! 4867: ** interface fixed, support it indefinitely, and remove this comment.
! 4868: */
! 4869:
! 4870: /*
! 4871: ** Structures used by the virtual table interface
! 4872: */
! 4873: typedef struct sqlite3_vtab sqlite3_vtab;
! 4874: typedef struct sqlite3_index_info sqlite3_index_info;
! 4875: typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
! 4876: typedef struct sqlite3_module sqlite3_module;
! 4877:
! 4878: /*
! 4879: ** CAPI3REF: Virtual Table Object
! 4880: ** KEYWORDS: sqlite3_module {virtual table module}
! 4881: **
! 4882: ** This structure, sometimes called a "virtual table module",
! 4883: ** defines the implementation of a [virtual tables].
! 4884: ** This structure consists mostly of methods for the module.
! 4885: **
! 4886: ** ^A virtual table module is created by filling in a persistent
! 4887: ** instance of this structure and passing a pointer to that instance
! 4888: ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
! 4889: ** ^The registration remains valid until it is replaced by a different
! 4890: ** module or until the [database connection] closes. The content
! 4891: ** of this structure must not change while it is registered with
! 4892: ** any database connection.
! 4893: */
! 4894: struct sqlite3_module {
! 4895: int iVersion;
! 4896: int (*xCreate)(sqlite3*, void *pAux,
! 4897: int argc, const char *const*argv,
! 4898: sqlite3_vtab **ppVTab, char**);
! 4899: int (*xConnect)(sqlite3*, void *pAux,
! 4900: int argc, const char *const*argv,
! 4901: sqlite3_vtab **ppVTab, char**);
! 4902: int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
! 4903: int (*xDisconnect)(sqlite3_vtab *pVTab);
! 4904: int (*xDestroy)(sqlite3_vtab *pVTab);
! 4905: int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
! 4906: int (*xClose)(sqlite3_vtab_cursor*);
! 4907: int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
! 4908: int argc, sqlite3_value **argv);
! 4909: int (*xNext)(sqlite3_vtab_cursor*);
! 4910: int (*xEof)(sqlite3_vtab_cursor*);
! 4911: int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
! 4912: int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
! 4913: int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
! 4914: int (*xBegin)(sqlite3_vtab *pVTab);
! 4915: int (*xSync)(sqlite3_vtab *pVTab);
! 4916: int (*xCommit)(sqlite3_vtab *pVTab);
! 4917: int (*xRollback)(sqlite3_vtab *pVTab);
! 4918: int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
! 4919: void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
! 4920: void **ppArg);
! 4921: int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
! 4922: /* The methods above are in version 1 of the sqlite_module object. Those
! 4923: ** below are for version 2 and greater. */
! 4924: int (*xSavepoint)(sqlite3_vtab *pVTab, int);
! 4925: int (*xRelease)(sqlite3_vtab *pVTab, int);
! 4926: int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
! 4927: };
! 4928:
! 4929: /*
! 4930: ** CAPI3REF: Virtual Table Indexing Information
! 4931: ** KEYWORDS: sqlite3_index_info
! 4932: **
! 4933: ** The sqlite3_index_info structure and its substructures is used as part
! 4934: ** of the [virtual table] interface to
! 4935: ** pass information into and receive the reply from the [xBestIndex]
! 4936: ** method of a [virtual table module]. The fields under **Inputs** are the
! 4937: ** inputs to xBestIndex and are read-only. xBestIndex inserts its
! 4938: ** results into the **Outputs** fields.
! 4939: **
! 4940: ** ^(The aConstraint[] array records WHERE clause constraints of the form:
! 4941: **
! 4942: ** <blockquote>column OP expr</blockquote>
! 4943: **
! 4944: ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
! 4945: ** stored in aConstraint[].op using one of the
! 4946: ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
! 4947: ** ^(The index of the column is stored in
! 4948: ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
! 4949: ** expr on the right-hand side can be evaluated (and thus the constraint
! 4950: ** is usable) and false if it cannot.)^
! 4951: **
! 4952: ** ^The optimizer automatically inverts terms of the form "expr OP column"
! 4953: ** and makes other simplifications to the WHERE clause in an attempt to
! 4954: ** get as many WHERE clause terms into the form shown above as possible.
! 4955: ** ^The aConstraint[] array only reports WHERE clause terms that are
! 4956: ** relevant to the particular virtual table being queried.
! 4957: **
! 4958: ** ^Information about the ORDER BY clause is stored in aOrderBy[].
! 4959: ** ^Each term of aOrderBy records a column of the ORDER BY clause.
! 4960: **
! 4961: ** The [xBestIndex] method must fill aConstraintUsage[] with information
! 4962: ** about what parameters to pass to xFilter. ^If argvIndex>0 then
! 4963: ** the right-hand side of the corresponding aConstraint[] is evaluated
! 4964: ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
! 4965: ** is true, then the constraint is assumed to be fully handled by the
! 4966: ** virtual table and is not checked again by SQLite.)^
! 4967: **
! 4968: ** ^The idxNum and idxPtr values are recorded and passed into the
! 4969: ** [xFilter] method.
! 4970: ** ^[sqlite3_free()] is used to free idxPtr if and only if
! 4971: ** needToFreeIdxPtr is true.
! 4972: **
! 4973: ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
! 4974: ** the correct order to satisfy the ORDER BY clause so that no separate
! 4975: ** sorting step is required.
! 4976: **
! 4977: ** ^The estimatedCost value is an estimate of the cost of doing the
! 4978: ** particular lookup. A full scan of a table with N entries should have
! 4979: ** a cost of N. A binary search of a table of N entries should have a
! 4980: ** cost of approximately log(N).
! 4981: */
! 4982: struct sqlite3_index_info {
! 4983: /* Inputs */
! 4984: int nConstraint; /* Number of entries in aConstraint */
! 4985: struct sqlite3_index_constraint {
! 4986: int iColumn; /* Column on left-hand side of constraint */
! 4987: unsigned char op; /* Constraint operator */
! 4988: unsigned char usable; /* True if this constraint is usable */
! 4989: int iTermOffset; /* Used internally - xBestIndex should ignore */
! 4990: } *aConstraint; /* Table of WHERE clause constraints */
! 4991: int nOrderBy; /* Number of terms in the ORDER BY clause */
! 4992: struct sqlite3_index_orderby {
! 4993: int iColumn; /* Column number */
! 4994: unsigned char desc; /* True for DESC. False for ASC. */
! 4995: } *aOrderBy; /* The ORDER BY clause */
! 4996: /* Outputs */
! 4997: struct sqlite3_index_constraint_usage {
! 4998: int argvIndex; /* if >0, constraint is part of argv to xFilter */
! 4999: unsigned char omit; /* Do not code a test for this constraint */
! 5000: } *aConstraintUsage;
! 5001: int idxNum; /* Number used to identify the index */
! 5002: char *idxStr; /* String, possibly obtained from sqlite3_malloc */
! 5003: int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
! 5004: int orderByConsumed; /* True if output is already ordered */
! 5005: double estimatedCost; /* Estimated cost of using this index */
! 5006: };
! 5007:
! 5008: /*
! 5009: ** CAPI3REF: Virtual Table Constraint Operator Codes
! 5010: **
! 5011: ** These macros defined the allowed values for the
! 5012: ** [sqlite3_index_info].aConstraint[].op field. Each value represents
! 5013: ** an operator that is part of a constraint term in the wHERE clause of
! 5014: ** a query that uses a [virtual table].
! 5015: */
! 5016: #define SQLITE_INDEX_CONSTRAINT_EQ 2
! 5017: #define SQLITE_INDEX_CONSTRAINT_GT 4
! 5018: #define SQLITE_INDEX_CONSTRAINT_LE 8
! 5019: #define SQLITE_INDEX_CONSTRAINT_LT 16
! 5020: #define SQLITE_INDEX_CONSTRAINT_GE 32
! 5021: #define SQLITE_INDEX_CONSTRAINT_MATCH 64
! 5022:
! 5023: /*
! 5024: ** CAPI3REF: Register A Virtual Table Implementation
! 5025: **
! 5026: ** ^These routines are used to register a new [virtual table module] name.
! 5027: ** ^Module names must be registered before
! 5028: ** creating a new [virtual table] using the module and before using a
! 5029: ** preexisting [virtual table] for the module.
! 5030: **
! 5031: ** ^The module name is registered on the [database connection] specified
! 5032: ** by the first parameter. ^The name of the module is given by the
! 5033: ** second parameter. ^The third parameter is a pointer to
! 5034: ** the implementation of the [virtual table module]. ^The fourth
! 5035: ** parameter is an arbitrary client data pointer that is passed through
! 5036: ** into the [xCreate] and [xConnect] methods of the virtual table module
! 5037: ** when a new virtual table is be being created or reinitialized.
! 5038: **
! 5039: ** ^The sqlite3_create_module_v2() interface has a fifth parameter which
! 5040: ** is a pointer to a destructor for the pClientData. ^SQLite will
! 5041: ** invoke the destructor function (if it is not NULL) when SQLite
! 5042: ** no longer needs the pClientData pointer. ^The destructor will also
! 5043: ** be invoked if the call to sqlite3_create_module_v2() fails.
! 5044: ** ^The sqlite3_create_module()
! 5045: ** interface is equivalent to sqlite3_create_module_v2() with a NULL
! 5046: ** destructor.
! 5047: */
! 5048: int sqlite3_create_module(
! 5049: sqlite3 *db, /* SQLite connection to register module with */
! 5050: const char *zName, /* Name of the module */
! 5051: const sqlite3_module *p, /* Methods for the module */
! 5052: void *pClientData /* Client data for xCreate/xConnect */
! 5053: );
! 5054: int sqlite3_create_module_v2(
! 5055: sqlite3 *db, /* SQLite connection to register module with */
! 5056: const char *zName, /* Name of the module */
! 5057: const sqlite3_module *p, /* Methods for the module */
! 5058: void *pClientData, /* Client data for xCreate/xConnect */
! 5059: void(*xDestroy)(void*) /* Module destructor function */
! 5060: );
! 5061:
! 5062: /*
! 5063: ** CAPI3REF: Virtual Table Instance Object
! 5064: ** KEYWORDS: sqlite3_vtab
! 5065: **
! 5066: ** Every [virtual table module] implementation uses a subclass
! 5067: ** of this object to describe a particular instance
! 5068: ** of the [virtual table]. Each subclass will
! 5069: ** be tailored to the specific needs of the module implementation.
! 5070: ** The purpose of this superclass is to define certain fields that are
! 5071: ** common to all module implementations.
! 5072: **
! 5073: ** ^Virtual tables methods can set an error message by assigning a
! 5074: ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
! 5075: ** take care that any prior string is freed by a call to [sqlite3_free()]
! 5076: ** prior to assigning a new string to zErrMsg. ^After the error message
! 5077: ** is delivered up to the client application, the string will be automatically
! 5078: ** freed by sqlite3_free() and the zErrMsg field will be zeroed.
! 5079: */
! 5080: struct sqlite3_vtab {
! 5081: const sqlite3_module *pModule; /* The module for this virtual table */
! 5082: int nRef; /* NO LONGER USED */
! 5083: char *zErrMsg; /* Error message from sqlite3_mprintf() */
! 5084: /* Virtual table implementations will typically add additional fields */
! 5085: };
! 5086:
! 5087: /*
! 5088: ** CAPI3REF: Virtual Table Cursor Object
! 5089: ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
! 5090: **
! 5091: ** Every [virtual table module] implementation uses a subclass of the
! 5092: ** following structure to describe cursors that point into the
! 5093: ** [virtual table] and are used
! 5094: ** to loop through the virtual table. Cursors are created using the
! 5095: ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
! 5096: ** by the [sqlite3_module.xClose | xClose] method. Cursors are used
! 5097: ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
! 5098: ** of the module. Each module implementation will define
! 5099: ** the content of a cursor structure to suit its own needs.
! 5100: **
! 5101: ** This superclass exists in order to define fields of the cursor that
! 5102: ** are common to all implementations.
! 5103: */
! 5104: struct sqlite3_vtab_cursor {
! 5105: sqlite3_vtab *pVtab; /* Virtual table of this cursor */
! 5106: /* Virtual table implementations will typically add additional fields */
! 5107: };
! 5108:
! 5109: /*
! 5110: ** CAPI3REF: Declare The Schema Of A Virtual Table
! 5111: **
! 5112: ** ^The [xCreate] and [xConnect] methods of a
! 5113: ** [virtual table module] call this interface
! 5114: ** to declare the format (the names and datatypes of the columns) of
! 5115: ** the virtual tables they implement.
! 5116: */
! 5117: int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
! 5118:
! 5119: /*
! 5120: ** CAPI3REF: Overload A Function For A Virtual Table
! 5121: **
! 5122: ** ^(Virtual tables can provide alternative implementations of functions
! 5123: ** using the [xFindFunction] method of the [virtual table module].
! 5124: ** But global versions of those functions
! 5125: ** must exist in order to be overloaded.)^
! 5126: **
! 5127: ** ^(This API makes sure a global version of a function with a particular
! 5128: ** name and number of parameters exists. If no such function exists
! 5129: ** before this API is called, a new function is created.)^ ^The implementation
! 5130: ** of the new function always causes an exception to be thrown. So
! 5131: ** the new function is not good for anything by itself. Its only
! 5132: ** purpose is to be a placeholder function that can be overloaded
! 5133: ** by a [virtual table].
! 5134: */
! 5135: int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
! 5136:
! 5137: /*
! 5138: ** The interface to the virtual-table mechanism defined above (back up
! 5139: ** to a comment remarkably similar to this one) is currently considered
! 5140: ** to be experimental. The interface might change in incompatible ways.
! 5141: ** If this is a problem for you, do not use the interface at this time.
! 5142: **
! 5143: ** When the virtual-table mechanism stabilizes, we will declare the
! 5144: ** interface fixed, support it indefinitely, and remove this comment.
! 5145: */
! 5146:
! 5147: /*
! 5148: ** CAPI3REF: A Handle To An Open BLOB
! 5149: ** KEYWORDS: {BLOB handle} {BLOB handles}
! 5150: **
! 5151: ** An instance of this object represents an open BLOB on which
! 5152: ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
! 5153: ** ^Objects of this type are created by [sqlite3_blob_open()]
! 5154: ** and destroyed by [sqlite3_blob_close()].
! 5155: ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
! 5156: ** can be used to read or write small subsections of the BLOB.
! 5157: ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
! 5158: */
! 5159: typedef struct sqlite3_blob sqlite3_blob;
! 5160:
! 5161: /*
! 5162: ** CAPI3REF: Open A BLOB For Incremental I/O
! 5163: **
! 5164: ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
! 5165: ** in row iRow, column zColumn, table zTable in database zDb;
! 5166: ** in other words, the same BLOB that would be selected by:
! 5167: **
! 5168: ** <pre>
! 5169: ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
! 5170: ** </pre>)^
! 5171: **
! 5172: ** ^If the flags parameter is non-zero, then the BLOB is opened for read
! 5173: ** and write access. ^If it is zero, the BLOB is opened for read access.
! 5174: ** ^It is not possible to open a column that is part of an index or primary
! 5175: ** key for writing. ^If [foreign key constraints] are enabled, it is
! 5176: ** not possible to open a column that is part of a [child key] for writing.
! 5177: **
! 5178: ** ^Note that the database name is not the filename that contains
! 5179: ** the database but rather the symbolic name of the database that
! 5180: ** appears after the AS keyword when the database is connected using [ATTACH].
! 5181: ** ^For the main database file, the database name is "main".
! 5182: ** ^For TEMP tables, the database name is "temp".
! 5183: **
! 5184: ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
! 5185: ** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
! 5186: ** to be a null pointer.)^
! 5187: ** ^This function sets the [database connection] error code and message
! 5188: ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
! 5189: ** functions. ^Note that the *ppBlob variable is always initialized in a
! 5190: ** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
! 5191: ** regardless of the success or failure of this routine.
! 5192: **
! 5193: ** ^(If the row that a BLOB handle points to is modified by an
! 5194: ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
! 5195: ** then the BLOB handle is marked as "expired".
! 5196: ** This is true if any column of the row is changed, even a column
! 5197: ** other than the one the BLOB handle is open on.)^
! 5198: ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
! 5199: ** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
! 5200: ** ^(Changes written into a BLOB prior to the BLOB expiring are not
! 5201: ** rolled back by the expiration of the BLOB. Such changes will eventually
! 5202: ** commit if the transaction continues to completion.)^
! 5203: **
! 5204: ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
! 5205: ** the opened blob. ^The size of a blob may not be changed by this
! 5206: ** interface. Use the [UPDATE] SQL command to change the size of a
! 5207: ** blob.
! 5208: **
! 5209: ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
! 5210: ** and the built-in [zeroblob] SQL function can be used, if desired,
! 5211: ** to create an empty, zero-filled blob in which to read or write using
! 5212: ** this interface.
! 5213: **
! 5214: ** To avoid a resource leak, every open [BLOB handle] should eventually
! 5215: ** be released by a call to [sqlite3_blob_close()].
! 5216: */
! 5217: int sqlite3_blob_open(
! 5218: sqlite3*,
! 5219: const char *zDb,
! 5220: const char *zTable,
! 5221: const char *zColumn,
! 5222: sqlite3_int64 iRow,
! 5223: int flags,
! 5224: sqlite3_blob **ppBlob
! 5225: );
! 5226:
! 5227: /*
! 5228: ** CAPI3REF: Move a BLOB Handle to a New Row
! 5229: **
! 5230: ** ^This function is used to move an existing blob handle so that it points
! 5231: ** to a different row of the same database table. ^The new row is identified
! 5232: ** by the rowid value passed as the second argument. Only the row can be
! 5233: ** changed. ^The database, table and column on which the blob handle is open
! 5234: ** remain the same. Moving an existing blob handle to a new row can be
! 5235: ** faster than closing the existing handle and opening a new one.
! 5236: **
! 5237: ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
! 5238: ** it must exist and there must be either a blob or text value stored in
! 5239: ** the nominated column.)^ ^If the new row is not present in the table, or if
! 5240: ** it does not contain a blob or text value, or if another error occurs, an
! 5241: ** SQLite error code is returned and the blob handle is considered aborted.
! 5242: ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
! 5243: ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
! 5244: ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
! 5245: ** always returns zero.
! 5246: **
! 5247: ** ^This function sets the database handle error code and message.
! 5248: */
! 5249: SQLITE_EXPERIMENTAL int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
! 5250:
! 5251: /*
! 5252: ** CAPI3REF: Close A BLOB Handle
! 5253: **
! 5254: ** ^Closes an open [BLOB handle].
! 5255: **
! 5256: ** ^Closing a BLOB shall cause the current transaction to commit
! 5257: ** if there are no other BLOBs, no pending prepared statements, and the
! 5258: ** database connection is in [autocommit mode].
! 5259: ** ^If any writes were made to the BLOB, they might be held in cache
! 5260: ** until the close operation if they will fit.
! 5261: **
! 5262: ** ^(Closing the BLOB often forces the changes
! 5263: ** out to disk and so if any I/O errors occur, they will likely occur
! 5264: ** at the time when the BLOB is closed. Any errors that occur during
! 5265: ** closing are reported as a non-zero return value.)^
! 5266: **
! 5267: ** ^(The BLOB is closed unconditionally. Even if this routine returns
! 5268: ** an error code, the BLOB is still closed.)^
! 5269: **
! 5270: ** ^Calling this routine with a null pointer (such as would be returned
! 5271: ** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
! 5272: */
! 5273: int sqlite3_blob_close(sqlite3_blob *);
! 5274:
! 5275: /*
! 5276: ** CAPI3REF: Return The Size Of An Open BLOB
! 5277: **
! 5278: ** ^Returns the size in bytes of the BLOB accessible via the
! 5279: ** successfully opened [BLOB handle] in its only argument. ^The
! 5280: ** incremental blob I/O routines can only read or overwriting existing
! 5281: ** blob content; they cannot change the size of a blob.
! 5282: **
! 5283: ** This routine only works on a [BLOB handle] which has been created
! 5284: ** by a prior successful call to [sqlite3_blob_open()] and which has not
! 5285: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
! 5286: ** to this routine results in undefined and probably undesirable behavior.
! 5287: */
! 5288: int sqlite3_blob_bytes(sqlite3_blob *);
! 5289:
! 5290: /*
! 5291: ** CAPI3REF: Read Data From A BLOB Incrementally
! 5292: **
! 5293: ** ^(This function is used to read data from an open [BLOB handle] into a
! 5294: ** caller-supplied buffer. N bytes of data are copied into buffer Z
! 5295: ** from the open BLOB, starting at offset iOffset.)^
! 5296: **
! 5297: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
! 5298: ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
! 5299: ** less than zero, [SQLITE_ERROR] is returned and no data is read.
! 5300: ** ^The size of the blob (and hence the maximum value of N+iOffset)
! 5301: ** can be determined using the [sqlite3_blob_bytes()] interface.
! 5302: **
! 5303: ** ^An attempt to read from an expired [BLOB handle] fails with an
! 5304: ** error code of [SQLITE_ABORT].
! 5305: **
! 5306: ** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
! 5307: ** Otherwise, an [error code] or an [extended error code] is returned.)^
! 5308: **
! 5309: ** This routine only works on a [BLOB handle] which has been created
! 5310: ** by a prior successful call to [sqlite3_blob_open()] and which has not
! 5311: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
! 5312: ** to this routine results in undefined and probably undesirable behavior.
! 5313: **
! 5314: ** See also: [sqlite3_blob_write()].
! 5315: */
! 5316: int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
! 5317:
! 5318: /*
! 5319: ** CAPI3REF: Write Data Into A BLOB Incrementally
! 5320: **
! 5321: ** ^This function is used to write data into an open [BLOB handle] from a
! 5322: ** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
! 5323: ** into the open BLOB, starting at offset iOffset.
! 5324: **
! 5325: ** ^If the [BLOB handle] passed as the first argument was not opened for
! 5326: ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
! 5327: ** this function returns [SQLITE_READONLY].
! 5328: **
! 5329: ** ^This function may only modify the contents of the BLOB; it is
! 5330: ** not possible to increase the size of a BLOB using this API.
! 5331: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
! 5332: ** [SQLITE_ERROR] is returned and no data is written. ^If N is
! 5333: ** less than zero [SQLITE_ERROR] is returned and no data is written.
! 5334: ** The size of the BLOB (and hence the maximum value of N+iOffset)
! 5335: ** can be determined using the [sqlite3_blob_bytes()] interface.
! 5336: **
! 5337: ** ^An attempt to write to an expired [BLOB handle] fails with an
! 5338: ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
! 5339: ** before the [BLOB handle] expired are not rolled back by the
! 5340: ** expiration of the handle, though of course those changes might
! 5341: ** have been overwritten by the statement that expired the BLOB handle
! 5342: ** or by other independent statements.
! 5343: **
! 5344: ** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
! 5345: ** Otherwise, an [error code] or an [extended error code] is returned.)^
! 5346: **
! 5347: ** This routine only works on a [BLOB handle] which has been created
! 5348: ** by a prior successful call to [sqlite3_blob_open()] and which has not
! 5349: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
! 5350: ** to this routine results in undefined and probably undesirable behavior.
! 5351: **
! 5352: ** See also: [sqlite3_blob_read()].
! 5353: */
! 5354: int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
! 5355:
! 5356: /*
! 5357: ** CAPI3REF: Virtual File System Objects
! 5358: **
! 5359: ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
! 5360: ** that SQLite uses to interact
! 5361: ** with the underlying operating system. Most SQLite builds come with a
! 5362: ** single default VFS that is appropriate for the host computer.
! 5363: ** New VFSes can be registered and existing VFSes can be unregistered.
! 5364: ** The following interfaces are provided.
! 5365: **
! 5366: ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
! 5367: ** ^Names are case sensitive.
! 5368: ** ^Names are zero-terminated UTF-8 strings.
! 5369: ** ^If there is no match, a NULL pointer is returned.
! 5370: ** ^If zVfsName is NULL then the default VFS is returned.
! 5371: **
! 5372: ** ^New VFSes are registered with sqlite3_vfs_register().
! 5373: ** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
! 5374: ** ^The same VFS can be registered multiple times without injury.
! 5375: ** ^To make an existing VFS into the default VFS, register it again
! 5376: ** with the makeDflt flag set. If two different VFSes with the
! 5377: ** same name are registered, the behavior is undefined. If a
! 5378: ** VFS is registered with a name that is NULL or an empty string,
! 5379: ** then the behavior is undefined.
! 5380: **
! 5381: ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
! 5382: ** ^(If the default VFS is unregistered, another VFS is chosen as
! 5383: ** the default. The choice for the new VFS is arbitrary.)^
! 5384: */
! 5385: sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
! 5386: int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
! 5387: int sqlite3_vfs_unregister(sqlite3_vfs*);
! 5388:
! 5389: /*
! 5390: ** CAPI3REF: Mutexes
! 5391: **
! 5392: ** The SQLite core uses these routines for thread
! 5393: ** synchronization. Though they are intended for internal
! 5394: ** use by SQLite, code that links against SQLite is
! 5395: ** permitted to use any of these routines.
! 5396: **
! 5397: ** The SQLite source code contains multiple implementations
! 5398: ** of these mutex routines. An appropriate implementation
! 5399: ** is selected automatically at compile-time. ^(The following
! 5400: ** implementations are available in the SQLite core:
! 5401: **
! 5402: ** <ul>
! 5403: ** <li> SQLITE_MUTEX_OS2
! 5404: ** <li> SQLITE_MUTEX_PTHREADS
! 5405: ** <li> SQLITE_MUTEX_W32
! 5406: ** <li> SQLITE_MUTEX_NOOP
! 5407: ** </ul>)^
! 5408: **
! 5409: ** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
! 5410: ** that does no real locking and is appropriate for use in
! 5411: ** a single-threaded application. ^The SQLITE_MUTEX_OS2,
! 5412: ** SQLITE_MUTEX_PTHREADS, and SQLITE_MUTEX_W32 implementations
! 5413: ** are appropriate for use on OS/2, Unix, and Windows.
! 5414: **
! 5415: ** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
! 5416: ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
! 5417: ** implementation is included with the library. In this case the
! 5418: ** application must supply a custom mutex implementation using the
! 5419: ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
! 5420: ** before calling sqlite3_initialize() or any other public sqlite3_
! 5421: ** function that calls sqlite3_initialize().)^
! 5422: **
! 5423: ** ^The sqlite3_mutex_alloc() routine allocates a new
! 5424: ** mutex and returns a pointer to it. ^If it returns NULL
! 5425: ** that means that a mutex could not be allocated. ^SQLite
! 5426: ** will unwind its stack and return an error. ^(The argument
! 5427: ** to sqlite3_mutex_alloc() is one of these integer constants:
! 5428: **
! 5429: ** <ul>
! 5430: ** <li> SQLITE_MUTEX_FAST
! 5431: ** <li> SQLITE_MUTEX_RECURSIVE
! 5432: ** <li> SQLITE_MUTEX_STATIC_MASTER
! 5433: ** <li> SQLITE_MUTEX_STATIC_MEM
! 5434: ** <li> SQLITE_MUTEX_STATIC_MEM2
! 5435: ** <li> SQLITE_MUTEX_STATIC_PRNG
! 5436: ** <li> SQLITE_MUTEX_STATIC_LRU
! 5437: ** <li> SQLITE_MUTEX_STATIC_LRU2
! 5438: ** </ul>)^
! 5439: **
! 5440: ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
! 5441: ** cause sqlite3_mutex_alloc() to create
! 5442: ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
! 5443: ** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
! 5444: ** The mutex implementation does not need to make a distinction
! 5445: ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
! 5446: ** not want to. ^SQLite will only request a recursive mutex in
! 5447: ** cases where it really needs one. ^If a faster non-recursive mutex
! 5448: ** implementation is available on the host platform, the mutex subsystem
! 5449: ** might return such a mutex in response to SQLITE_MUTEX_FAST.
! 5450: **
! 5451: ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
! 5452: ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
! 5453: ** a pointer to a static preexisting mutex. ^Six static mutexes are
! 5454: ** used by the current version of SQLite. Future versions of SQLite
! 5455: ** may add additional static mutexes. Static mutexes are for internal
! 5456: ** use by SQLite only. Applications that use SQLite mutexes should
! 5457: ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
! 5458: ** SQLITE_MUTEX_RECURSIVE.
! 5459: **
! 5460: ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
! 5461: ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
! 5462: ** returns a different mutex on every call. ^But for the static
! 5463: ** mutex types, the same mutex is returned on every call that has
! 5464: ** the same type number.
! 5465: **
! 5466: ** ^The sqlite3_mutex_free() routine deallocates a previously
! 5467: ** allocated dynamic mutex. ^SQLite is careful to deallocate every
! 5468: ** dynamic mutex that it allocates. The dynamic mutexes must not be in
! 5469: ** use when they are deallocated. Attempting to deallocate a static
! 5470: ** mutex results in undefined behavior. ^SQLite never deallocates
! 5471: ** a static mutex.
! 5472: **
! 5473: ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
! 5474: ** to enter a mutex. ^If another thread is already within the mutex,
! 5475: ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
! 5476: ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
! 5477: ** upon successful entry. ^(Mutexes created using
! 5478: ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
! 5479: ** In such cases the,
! 5480: ** mutex must be exited an equal number of times before another thread
! 5481: ** can enter.)^ ^(If the same thread tries to enter any other
! 5482: ** kind of mutex more than once, the behavior is undefined.
! 5483: ** SQLite will never exhibit
! 5484: ** such behavior in its own use of mutexes.)^
! 5485: **
! 5486: ** ^(Some systems (for example, Windows 95) do not support the operation
! 5487: ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
! 5488: ** will always return SQLITE_BUSY. The SQLite core only ever uses
! 5489: ** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
! 5490: **
! 5491: ** ^The sqlite3_mutex_leave() routine exits a mutex that was
! 5492: ** previously entered by the same thread. ^(The behavior
! 5493: ** is undefined if the mutex is not currently entered by the
! 5494: ** calling thread or is not currently allocated. SQLite will
! 5495: ** never do either.)^
! 5496: **
! 5497: ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
! 5498: ** sqlite3_mutex_leave() is a NULL pointer, then all three routines
! 5499: ** behave as no-ops.
! 5500: **
! 5501: ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
! 5502: */
! 5503: sqlite3_mutex *sqlite3_mutex_alloc(int);
! 5504: void sqlite3_mutex_free(sqlite3_mutex*);
! 5505: void sqlite3_mutex_enter(sqlite3_mutex*);
! 5506: int sqlite3_mutex_try(sqlite3_mutex*);
! 5507: void sqlite3_mutex_leave(sqlite3_mutex*);
! 5508:
! 5509: /*
! 5510: ** CAPI3REF: Mutex Methods Object
! 5511: **
! 5512: ** An instance of this structure defines the low-level routines
! 5513: ** used to allocate and use mutexes.
! 5514: **
! 5515: ** Usually, the default mutex implementations provided by SQLite are
! 5516: ** sufficient, however the user has the option of substituting a custom
! 5517: ** implementation for specialized deployments or systems for which SQLite
! 5518: ** does not provide a suitable implementation. In this case, the user
! 5519: ** creates and populates an instance of this structure to pass
! 5520: ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
! 5521: ** Additionally, an instance of this structure can be used as an
! 5522: ** output variable when querying the system for the current mutex
! 5523: ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
! 5524: **
! 5525: ** ^The xMutexInit method defined by this structure is invoked as
! 5526: ** part of system initialization by the sqlite3_initialize() function.
! 5527: ** ^The xMutexInit routine is called by SQLite exactly once for each
! 5528: ** effective call to [sqlite3_initialize()].
! 5529: **
! 5530: ** ^The xMutexEnd method defined by this structure is invoked as
! 5531: ** part of system shutdown by the sqlite3_shutdown() function. The
! 5532: ** implementation of this method is expected to release all outstanding
! 5533: ** resources obtained by the mutex methods implementation, especially
! 5534: ** those obtained by the xMutexInit method. ^The xMutexEnd()
! 5535: ** interface is invoked exactly once for each call to [sqlite3_shutdown()].
! 5536: **
! 5537: ** ^(The remaining seven methods defined by this structure (xMutexAlloc,
! 5538: ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
! 5539: ** xMutexNotheld) implement the following interfaces (respectively):
! 5540: **
! 5541: ** <ul>
! 5542: ** <li> [sqlite3_mutex_alloc()] </li>
! 5543: ** <li> [sqlite3_mutex_free()] </li>
! 5544: ** <li> [sqlite3_mutex_enter()] </li>
! 5545: ** <li> [sqlite3_mutex_try()] </li>
! 5546: ** <li> [sqlite3_mutex_leave()] </li>
! 5547: ** <li> [sqlite3_mutex_held()] </li>
! 5548: ** <li> [sqlite3_mutex_notheld()] </li>
! 5549: ** </ul>)^
! 5550: **
! 5551: ** The only difference is that the public sqlite3_XXX functions enumerated
! 5552: ** above silently ignore any invocations that pass a NULL pointer instead
! 5553: ** of a valid mutex handle. The implementations of the methods defined
! 5554: ** by this structure are not required to handle this case, the results
! 5555: ** of passing a NULL pointer instead of a valid mutex handle are undefined
! 5556: ** (i.e. it is acceptable to provide an implementation that segfaults if
! 5557: ** it is passed a NULL pointer).
! 5558: **
! 5559: ** The xMutexInit() method must be threadsafe. ^It must be harmless to
! 5560: ** invoke xMutexInit() multiple times within the same process and without
! 5561: ** intervening calls to xMutexEnd(). Second and subsequent calls to
! 5562: ** xMutexInit() must be no-ops.
! 5563: **
! 5564: ** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
! 5565: ** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory
! 5566: ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
! 5567: ** memory allocation for a fast or recursive mutex.
! 5568: **
! 5569: ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
! 5570: ** called, but only if the prior call to xMutexInit returned SQLITE_OK.
! 5571: ** If xMutexInit fails in any way, it is expected to clean up after itself
! 5572: ** prior to returning.
! 5573: */
! 5574: typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
! 5575: struct sqlite3_mutex_methods {
! 5576: int (*xMutexInit)(void);
! 5577: int (*xMutexEnd)(void);
! 5578: sqlite3_mutex *(*xMutexAlloc)(int);
! 5579: void (*xMutexFree)(sqlite3_mutex *);
! 5580: void (*xMutexEnter)(sqlite3_mutex *);
! 5581: int (*xMutexTry)(sqlite3_mutex *);
! 5582: void (*xMutexLeave)(sqlite3_mutex *);
! 5583: int (*xMutexHeld)(sqlite3_mutex *);
! 5584: int (*xMutexNotheld)(sqlite3_mutex *);
! 5585: };
! 5586:
! 5587: /*
! 5588: ** CAPI3REF: Mutex Verification Routines
! 5589: **
! 5590: ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
! 5591: ** are intended for use inside assert() statements. ^The SQLite core
! 5592: ** never uses these routines except inside an assert() and applications
! 5593: ** are advised to follow the lead of the core. ^The SQLite core only
! 5594: ** provides implementations for these routines when it is compiled
! 5595: ** with the SQLITE_DEBUG flag. ^External mutex implementations
! 5596: ** are only required to provide these routines if SQLITE_DEBUG is
! 5597: ** defined and if NDEBUG is not defined.
! 5598: **
! 5599: ** ^These routines should return true if the mutex in their argument
! 5600: ** is held or not held, respectively, by the calling thread.
! 5601: **
! 5602: ** ^The implementation is not required to provide versions of these
! 5603: ** routines that actually work. If the implementation does not provide working
! 5604: ** versions of these routines, it should at least provide stubs that always
! 5605: ** return true so that one does not get spurious assertion failures.
! 5606: **
! 5607: ** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
! 5608: ** the routine should return 1. This seems counter-intuitive since
! 5609: ** clearly the mutex cannot be held if it does not exist. But
! 5610: ** the reason the mutex does not exist is because the build is not
! 5611: ** using mutexes. And we do not want the assert() containing the
! 5612: ** call to sqlite3_mutex_held() to fail, so a non-zero return is
! 5613: ** the appropriate thing to do. ^The sqlite3_mutex_notheld()
! 5614: ** interface should also return 1 when given a NULL pointer.
! 5615: */
! 5616: #ifndef NDEBUG
! 5617: int sqlite3_mutex_held(sqlite3_mutex*);
! 5618: int sqlite3_mutex_notheld(sqlite3_mutex*);
! 5619: #endif
! 5620:
! 5621: /*
! 5622: ** CAPI3REF: Mutex Types
! 5623: **
! 5624: ** The [sqlite3_mutex_alloc()] interface takes a single argument
! 5625: ** which is one of these integer constants.
! 5626: **
! 5627: ** The set of static mutexes may change from one SQLite release to the
! 5628: ** next. Applications that override the built-in mutex logic must be
! 5629: ** prepared to accommodate additional static mutexes.
! 5630: */
! 5631: #define SQLITE_MUTEX_FAST 0
! 5632: #define SQLITE_MUTEX_RECURSIVE 1
! 5633: #define SQLITE_MUTEX_STATIC_MASTER 2
! 5634: #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
! 5635: #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
! 5636: #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
! 5637: #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
! 5638: #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
! 5639: #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
! 5640: #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
! 5641:
! 5642: /*
! 5643: ** CAPI3REF: Retrieve the mutex for a database connection
! 5644: **
! 5645: ** ^This interface returns a pointer the [sqlite3_mutex] object that
! 5646: ** serializes access to the [database connection] given in the argument
! 5647: ** when the [threading mode] is Serialized.
! 5648: ** ^If the [threading mode] is Single-thread or Multi-thread then this
! 5649: ** routine returns a NULL pointer.
! 5650: */
! 5651: sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
! 5652:
! 5653: /*
! 5654: ** CAPI3REF: Low-Level Control Of Database Files
! 5655: **
! 5656: ** ^The [sqlite3_file_control()] interface makes a direct call to the
! 5657: ** xFileControl method for the [sqlite3_io_methods] object associated
! 5658: ** with a particular database identified by the second argument. ^The
! 5659: ** name of the database is "main" for the main database or "temp" for the
! 5660: ** TEMP database, or the name that appears after the AS keyword for
! 5661: ** databases that are added using the [ATTACH] SQL command.
! 5662: ** ^A NULL pointer can be used in place of "main" to refer to the
! 5663: ** main database file.
! 5664: ** ^The third and fourth parameters to this routine
! 5665: ** are passed directly through to the second and third parameters of
! 5666: ** the xFileControl method. ^The return value of the xFileControl
! 5667: ** method becomes the return value of this routine.
! 5668: **
! 5669: ** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
! 5670: ** a pointer to the underlying [sqlite3_file] object to be written into
! 5671: ** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER
! 5672: ** case is a short-circuit path which does not actually invoke the
! 5673: ** underlying sqlite3_io_methods.xFileControl method.
! 5674: **
! 5675: ** ^If the second parameter (zDbName) does not match the name of any
! 5676: ** open database file, then SQLITE_ERROR is returned. ^This error
! 5677: ** code is not remembered and will not be recalled by [sqlite3_errcode()]
! 5678: ** or [sqlite3_errmsg()]. The underlying xFileControl method might
! 5679: ** also return SQLITE_ERROR. There is no way to distinguish between
! 5680: ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
! 5681: ** xFileControl method.
! 5682: **
! 5683: ** See also: [SQLITE_FCNTL_LOCKSTATE]
! 5684: */
! 5685: int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
! 5686:
! 5687: /*
! 5688: ** CAPI3REF: Testing Interface
! 5689: **
! 5690: ** ^The sqlite3_test_control() interface is used to read out internal
! 5691: ** state of SQLite and to inject faults into SQLite for testing
! 5692: ** purposes. ^The first parameter is an operation code that determines
! 5693: ** the number, meaning, and operation of all subsequent parameters.
! 5694: **
! 5695: ** This interface is not for use by applications. It exists solely
! 5696: ** for verifying the correct operation of the SQLite library. Depending
! 5697: ** on how the SQLite library is compiled, this interface might not exist.
! 5698: **
! 5699: ** The details of the operation codes, their meanings, the parameters
! 5700: ** they take, and what they do are all subject to change without notice.
! 5701: ** Unlike most of the SQLite API, this function is not guaranteed to
! 5702: ** operate consistently from one release to the next.
! 5703: */
! 5704: int sqlite3_test_control(int op, ...);
! 5705:
! 5706: /*
! 5707: ** CAPI3REF: Testing Interface Operation Codes
! 5708: **
! 5709: ** These constants are the valid operation code parameters used
! 5710: ** as the first argument to [sqlite3_test_control()].
! 5711: **
! 5712: ** These parameters and their meanings are subject to change
! 5713: ** without notice. These values are for testing purposes only.
! 5714: ** Applications should not use any of these parameters or the
! 5715: ** [sqlite3_test_control()] interface.
! 5716: */
! 5717: #define SQLITE_TESTCTRL_FIRST 5
! 5718: #define SQLITE_TESTCTRL_PRNG_SAVE 5
! 5719: #define SQLITE_TESTCTRL_PRNG_RESTORE 6
! 5720: #define SQLITE_TESTCTRL_PRNG_RESET 7
! 5721: #define SQLITE_TESTCTRL_BITVEC_TEST 8
! 5722: #define SQLITE_TESTCTRL_FAULT_INSTALL 9
! 5723: #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
! 5724: #define SQLITE_TESTCTRL_PENDING_BYTE 11
! 5725: #define SQLITE_TESTCTRL_ASSERT 12
! 5726: #define SQLITE_TESTCTRL_ALWAYS 13
! 5727: #define SQLITE_TESTCTRL_RESERVE 14
! 5728: #define SQLITE_TESTCTRL_OPTIMIZATIONS 15
! 5729: #define SQLITE_TESTCTRL_ISKEYWORD 16
! 5730: #define SQLITE_TESTCTRL_SCRATCHMALLOC 17
! 5731: #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
! 5732: #define SQLITE_TESTCTRL_EXPLAIN_STMT 19
! 5733: #define SQLITE_TESTCTRL_LAST 19
! 5734:
! 5735: /*
! 5736: ** CAPI3REF: SQLite Runtime Status
! 5737: **
! 5738: ** ^This interface is used to retrieve runtime status information
! 5739: ** about the performance of SQLite, and optionally to reset various
! 5740: ** highwater marks. ^The first argument is an integer code for
! 5741: ** the specific parameter to measure. ^(Recognized integer codes
! 5742: ** are of the form [status parameters | SQLITE_STATUS_...].)^
! 5743: ** ^The current value of the parameter is returned into *pCurrent.
! 5744: ** ^The highest recorded value is returned in *pHighwater. ^If the
! 5745: ** resetFlag is true, then the highest record value is reset after
! 5746: ** *pHighwater is written. ^(Some parameters do not record the highest
! 5747: ** value. For those parameters
! 5748: ** nothing is written into *pHighwater and the resetFlag is ignored.)^
! 5749: ** ^(Other parameters record only the highwater mark and not the current
! 5750: ** value. For these latter parameters nothing is written into *pCurrent.)^
! 5751: **
! 5752: ** ^The sqlite3_status() routine returns SQLITE_OK on success and a
! 5753: ** non-zero [error code] on failure.
! 5754: **
! 5755: ** This routine is threadsafe but is not atomic. This routine can be
! 5756: ** called while other threads are running the same or different SQLite
! 5757: ** interfaces. However the values returned in *pCurrent and
! 5758: ** *pHighwater reflect the status of SQLite at different points in time
! 5759: ** and it is possible that another thread might change the parameter
! 5760: ** in between the times when *pCurrent and *pHighwater are written.
! 5761: **
! 5762: ** See also: [sqlite3_db_status()]
! 5763: */
! 5764: int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
! 5765:
! 5766:
! 5767: /*
! 5768: ** CAPI3REF: Status Parameters
! 5769: ** KEYWORDS: {status parameters}
! 5770: **
! 5771: ** These integer constants designate various run-time status parameters
! 5772: ** that can be returned by [sqlite3_status()].
! 5773: **
! 5774: ** <dl>
! 5775: ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
! 5776: ** <dd>This parameter is the current amount of memory checked out
! 5777: ** using [sqlite3_malloc()], either directly or indirectly. The
! 5778: ** figure includes calls made to [sqlite3_malloc()] by the application
! 5779: ** and internal memory usage by the SQLite library. Scratch memory
! 5780: ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
! 5781: ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
! 5782: ** this parameter. The amount returned is the sum of the allocation
! 5783: ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
! 5784: **
! 5785: ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
! 5786: ** <dd>This parameter records the largest memory allocation request
! 5787: ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
! 5788: ** internal equivalents). Only the value returned in the
! 5789: ** *pHighwater parameter to [sqlite3_status()] is of interest.
! 5790: ** The value written into the *pCurrent parameter is undefined.</dd>)^
! 5791: **
! 5792: ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
! 5793: ** <dd>This parameter records the number of separate memory allocations
! 5794: ** currently checked out.</dd>)^
! 5795: **
! 5796: ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
! 5797: ** <dd>This parameter returns the number of pages used out of the
! 5798: ** [pagecache memory allocator] that was configured using
! 5799: ** [SQLITE_CONFIG_PAGECACHE]. The
! 5800: ** value returned is in pages, not in bytes.</dd>)^
! 5801: **
! 5802: ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
! 5803: ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
! 5804: ** <dd>This parameter returns the number of bytes of page cache
! 5805: ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
! 5806: ** buffer and where forced to overflow to [sqlite3_malloc()]. The
! 5807: ** returned value includes allocations that overflowed because they
! 5808: ** where too large (they were larger than the "sz" parameter to
! 5809: ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
! 5810: ** no space was left in the page cache.</dd>)^
! 5811: **
! 5812: ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
! 5813: ** <dd>This parameter records the largest memory allocation request
! 5814: ** handed to [pagecache memory allocator]. Only the value returned in the
! 5815: ** *pHighwater parameter to [sqlite3_status()] is of interest.
! 5816: ** The value written into the *pCurrent parameter is undefined.</dd>)^
! 5817: **
! 5818: ** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
! 5819: ** <dd>This parameter returns the number of allocations used out of the
! 5820: ** [scratch memory allocator] configured using
! 5821: ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
! 5822: ** in bytes. Since a single thread may only have one scratch allocation
! 5823: ** outstanding at time, this parameter also reports the number of threads
! 5824: ** using scratch memory at the same time.</dd>)^
! 5825: **
! 5826: ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
! 5827: ** <dd>This parameter returns the number of bytes of scratch memory
! 5828: ** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
! 5829: ** buffer and where forced to overflow to [sqlite3_malloc()]. The values
! 5830: ** returned include overflows because the requested allocation was too
! 5831: ** larger (that is, because the requested allocation was larger than the
! 5832: ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
! 5833: ** slots were available.
! 5834: ** </dd>)^
! 5835: **
! 5836: ** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
! 5837: ** <dd>This parameter records the largest memory allocation request
! 5838: ** handed to [scratch memory allocator]. Only the value returned in the
! 5839: ** *pHighwater parameter to [sqlite3_status()] is of interest.
! 5840: ** The value written into the *pCurrent parameter is undefined.</dd>)^
! 5841: **
! 5842: ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
! 5843: ** <dd>This parameter records the deepest parser stack. It is only
! 5844: ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
! 5845: ** </dl>
! 5846: **
! 5847: ** New status parameters may be added from time to time.
! 5848: */
! 5849: #define SQLITE_STATUS_MEMORY_USED 0
! 5850: #define SQLITE_STATUS_PAGECACHE_USED 1
! 5851: #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
! 5852: #define SQLITE_STATUS_SCRATCH_USED 3
! 5853: #define SQLITE_STATUS_SCRATCH_OVERFLOW 4
! 5854: #define SQLITE_STATUS_MALLOC_SIZE 5
! 5855: #define SQLITE_STATUS_PARSER_STACK 6
! 5856: #define SQLITE_STATUS_PAGECACHE_SIZE 7
! 5857: #define SQLITE_STATUS_SCRATCH_SIZE 8
! 5858: #define SQLITE_STATUS_MALLOC_COUNT 9
! 5859:
! 5860: /*
! 5861: ** CAPI3REF: Database Connection Status
! 5862: **
! 5863: ** ^This interface is used to retrieve runtime status information
! 5864: ** about a single [database connection]. ^The first argument is the
! 5865: ** database connection object to be interrogated. ^The second argument
! 5866: ** is an integer constant, taken from the set of
! 5867: ** [SQLITE_DBSTATUS options], that
! 5868: ** determines the parameter to interrogate. The set of
! 5869: ** [SQLITE_DBSTATUS options] is likely
! 5870: ** to grow in future releases of SQLite.
! 5871: **
! 5872: ** ^The current value of the requested parameter is written into *pCur
! 5873: ** and the highest instantaneous value is written into *pHiwtr. ^If
! 5874: ** the resetFlg is true, then the highest instantaneous value is
! 5875: ** reset back down to the current value.
! 5876: **
! 5877: ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
! 5878: ** non-zero [error code] on failure.
! 5879: **
! 5880: ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
! 5881: */
! 5882: int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
! 5883:
! 5884: /*
! 5885: ** CAPI3REF: Status Parameters for database connections
! 5886: ** KEYWORDS: {SQLITE_DBSTATUS options}
! 5887: **
! 5888: ** These constants are the available integer "verbs" that can be passed as
! 5889: ** the second argument to the [sqlite3_db_status()] interface.
! 5890: **
! 5891: ** New verbs may be added in future releases of SQLite. Existing verbs
! 5892: ** might be discontinued. Applications should check the return code from
! 5893: ** [sqlite3_db_status()] to make sure that the call worked.
! 5894: ** The [sqlite3_db_status()] interface will return a non-zero error code
! 5895: ** if a discontinued or unsupported verb is invoked.
! 5896: **
! 5897: ** <dl>
! 5898: ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
! 5899: ** <dd>This parameter returns the number of lookaside memory slots currently
! 5900: ** checked out.</dd>)^
! 5901: **
! 5902: ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
! 5903: ** <dd>This parameter returns the number malloc attempts that were
! 5904: ** satisfied using lookaside memory. Only the high-water value is meaningful;
! 5905: ** the current value is always zero.)^
! 5906: **
! 5907: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
! 5908: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
! 5909: ** <dd>This parameter returns the number malloc attempts that might have
! 5910: ** been satisfied using lookaside memory but failed due to the amount of
! 5911: ** memory requested being larger than the lookaside slot size.
! 5912: ** Only the high-water value is meaningful;
! 5913: ** the current value is always zero.)^
! 5914: **
! 5915: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
! 5916: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
! 5917: ** <dd>This parameter returns the number malloc attempts that might have
! 5918: ** been satisfied using lookaside memory but failed due to all lookaside
! 5919: ** memory already being in use.
! 5920: ** Only the high-water value is meaningful;
! 5921: ** the current value is always zero.)^
! 5922: **
! 5923: ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
! 5924: ** <dd>This parameter returns the approximate number of of bytes of heap
! 5925: ** memory used by all pager caches associated with the database connection.)^
! 5926: ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
! 5927: **
! 5928: ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
! 5929: ** <dd>This parameter returns the approximate number of of bytes of heap
! 5930: ** memory used to store the schema for all databases associated
! 5931: ** with the connection - main, temp, and any [ATTACH]-ed databases.)^
! 5932: ** ^The full amount of memory used by the schemas is reported, even if the
! 5933: ** schema memory is shared with other database connections due to
! 5934: ** [shared cache mode] being enabled.
! 5935: ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
! 5936: **
! 5937: ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
! 5938: ** <dd>This parameter returns the approximate number of of bytes of heap
! 5939: ** and lookaside memory used by all prepared statements associated with
! 5940: ** the database connection.)^
! 5941: ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
! 5942: ** </dd>
! 5943: **
! 5944: ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
! 5945: ** <dd>This parameter returns the number of pager cache hits that have
! 5946: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
! 5947: ** is always 0.
! 5948: ** </dd>
! 5949: **
! 5950: ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
! 5951: ** <dd>This parameter returns the number of pager cache misses that have
! 5952: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
! 5953: ** is always 0.
! 5954: ** </dd>
! 5955: ** </dl>
! 5956: */
! 5957: #define SQLITE_DBSTATUS_LOOKASIDE_USED 0
! 5958: #define SQLITE_DBSTATUS_CACHE_USED 1
! 5959: #define SQLITE_DBSTATUS_SCHEMA_USED 2
! 5960: #define SQLITE_DBSTATUS_STMT_USED 3
! 5961: #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
! 5962: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
! 5963: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
! 5964: #define SQLITE_DBSTATUS_CACHE_HIT 7
! 5965: #define SQLITE_DBSTATUS_CACHE_MISS 8
! 5966: #define SQLITE_DBSTATUS_MAX 8 /* Largest defined DBSTATUS */
! 5967:
! 5968:
! 5969: /*
! 5970: ** CAPI3REF: Prepared Statement Status
! 5971: **
! 5972: ** ^(Each prepared statement maintains various
! 5973: ** [SQLITE_STMTSTATUS counters] that measure the number
! 5974: ** of times it has performed specific operations.)^ These counters can
! 5975: ** be used to monitor the performance characteristics of the prepared
! 5976: ** statements. For example, if the number of table steps greatly exceeds
! 5977: ** the number of table searches or result rows, that would tend to indicate
! 5978: ** that the prepared statement is using a full table scan rather than
! 5979: ** an index.
! 5980: **
! 5981: ** ^(This interface is used to retrieve and reset counter values from
! 5982: ** a [prepared statement]. The first argument is the prepared statement
! 5983: ** object to be interrogated. The second argument
! 5984: ** is an integer code for a specific [SQLITE_STMTSTATUS counter]
! 5985: ** to be interrogated.)^
! 5986: ** ^The current value of the requested counter is returned.
! 5987: ** ^If the resetFlg is true, then the counter is reset to zero after this
! 5988: ** interface call returns.
! 5989: **
! 5990: ** See also: [sqlite3_status()] and [sqlite3_db_status()].
! 5991: */
! 5992: int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
! 5993:
! 5994: /*
! 5995: ** CAPI3REF: Status Parameters for prepared statements
! 5996: ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
! 5997: **
! 5998: ** These preprocessor macros define integer codes that name counter
! 5999: ** values associated with the [sqlite3_stmt_status()] interface.
! 6000: ** The meanings of the various counters are as follows:
! 6001: **
! 6002: ** <dl>
! 6003: ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
! 6004: ** <dd>^This is the number of times that SQLite has stepped forward in
! 6005: ** a table as part of a full table scan. Large numbers for this counter
! 6006: ** may indicate opportunities for performance improvement through
! 6007: ** careful use of indices.</dd>
! 6008: **
! 6009: ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
! 6010: ** <dd>^This is the number of sort operations that have occurred.
! 6011: ** A non-zero value in this counter may indicate an opportunity to
! 6012: ** improvement performance through careful use of indices.</dd>
! 6013: **
! 6014: ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
! 6015: ** <dd>^This is the number of rows inserted into transient indices that
! 6016: ** were created automatically in order to help joins run faster.
! 6017: ** A non-zero value in this counter may indicate an opportunity to
! 6018: ** improvement performance by adding permanent indices that do not
! 6019: ** need to be reinitialized each time the statement is run.</dd>
! 6020: ** </dl>
! 6021: */
! 6022: #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
! 6023: #define SQLITE_STMTSTATUS_SORT 2
! 6024: #define SQLITE_STMTSTATUS_AUTOINDEX 3
! 6025:
! 6026: /*
! 6027: ** CAPI3REF: Custom Page Cache Object
! 6028: **
! 6029: ** The sqlite3_pcache type is opaque. It is implemented by
! 6030: ** the pluggable module. The SQLite core has no knowledge of
! 6031: ** its size or internal structure and never deals with the
! 6032: ** sqlite3_pcache object except by holding and passing pointers
! 6033: ** to the object.
! 6034: **
! 6035: ** See [sqlite3_pcache_methods2] for additional information.
! 6036: */
! 6037: typedef struct sqlite3_pcache sqlite3_pcache;
! 6038:
! 6039: /*
! 6040: ** CAPI3REF: Custom Page Cache Object
! 6041: **
! 6042: ** The sqlite3_pcache_page object represents a single page in the
! 6043: ** page cache. The page cache will allocate instances of this
! 6044: ** object. Various methods of the page cache use pointers to instances
! 6045: ** of this object as parameters or as their return value.
! 6046: **
! 6047: ** See [sqlite3_pcache_methods2] for additional information.
! 6048: */
! 6049: typedef struct sqlite3_pcache_page sqlite3_pcache_page;
! 6050: struct sqlite3_pcache_page {
! 6051: void *pBuf; /* The content of the page */
! 6052: void *pExtra; /* Extra information associated with the page */
! 6053: };
! 6054:
! 6055: /*
! 6056: ** CAPI3REF: Application Defined Page Cache.
! 6057: ** KEYWORDS: {page cache}
! 6058: **
! 6059: ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
! 6060: ** register an alternative page cache implementation by passing in an
! 6061: ** instance of the sqlite3_pcache_methods2 structure.)^
! 6062: ** In many applications, most of the heap memory allocated by
! 6063: ** SQLite is used for the page cache.
! 6064: ** By implementing a
! 6065: ** custom page cache using this API, an application can better control
! 6066: ** the amount of memory consumed by SQLite, the way in which
! 6067: ** that memory is allocated and released, and the policies used to
! 6068: ** determine exactly which parts of a database file are cached and for
! 6069: ** how long.
! 6070: **
! 6071: ** The alternative page cache mechanism is an
! 6072: ** extreme measure that is only needed by the most demanding applications.
! 6073: ** The built-in page cache is recommended for most uses.
! 6074: **
! 6075: ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
! 6076: ** internal buffer by SQLite within the call to [sqlite3_config]. Hence
! 6077: ** the application may discard the parameter after the call to
! 6078: ** [sqlite3_config()] returns.)^
! 6079: **
! 6080: ** [[the xInit() page cache method]]
! 6081: ** ^(The xInit() method is called once for each effective
! 6082: ** call to [sqlite3_initialize()])^
! 6083: ** (usually only once during the lifetime of the process). ^(The xInit()
! 6084: ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
! 6085: ** The intent of the xInit() method is to set up global data structures
! 6086: ** required by the custom page cache implementation.
! 6087: ** ^(If the xInit() method is NULL, then the
! 6088: ** built-in default page cache is used instead of the application defined
! 6089: ** page cache.)^
! 6090: **
! 6091: ** [[the xShutdown() page cache method]]
! 6092: ** ^The xShutdown() method is called by [sqlite3_shutdown()].
! 6093: ** It can be used to clean up
! 6094: ** any outstanding resources before process shutdown, if required.
! 6095: ** ^The xShutdown() method may be NULL.
! 6096: **
! 6097: ** ^SQLite automatically serializes calls to the xInit method,
! 6098: ** so the xInit method need not be threadsafe. ^The
! 6099: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
! 6100: ** not need to be threadsafe either. All other methods must be threadsafe
! 6101: ** in multithreaded applications.
! 6102: **
! 6103: ** ^SQLite will never invoke xInit() more than once without an intervening
! 6104: ** call to xShutdown().
! 6105: **
! 6106: ** [[the xCreate() page cache methods]]
! 6107: ** ^SQLite invokes the xCreate() method to construct a new cache instance.
! 6108: ** SQLite will typically create one cache instance for each open database file,
! 6109: ** though this is not guaranteed. ^The
! 6110: ** first parameter, szPage, is the size in bytes of the pages that must
! 6111: ** be allocated by the cache. ^szPage will always a power of two. ^The
! 6112: ** second parameter szExtra is a number of bytes of extra storage
! 6113: ** associated with each page cache entry. ^The szExtra parameter will
! 6114: ** a number less than 250. SQLite will use the
! 6115: ** extra szExtra bytes on each page to store metadata about the underlying
! 6116: ** database page on disk. The value passed into szExtra depends
! 6117: ** on the SQLite version, the target platform, and how SQLite was compiled.
! 6118: ** ^The third argument to xCreate(), bPurgeable, is true if the cache being
! 6119: ** created will be used to cache database pages of a file stored on disk, or
! 6120: ** false if it is used for an in-memory database. The cache implementation
! 6121: ** does not have to do anything special based with the value of bPurgeable;
! 6122: ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
! 6123: ** never invoke xUnpin() except to deliberately delete a page.
! 6124: ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
! 6125: ** false will always have the "discard" flag set to true.
! 6126: ** ^Hence, a cache created with bPurgeable false will
! 6127: ** never contain any unpinned pages.
! 6128: **
! 6129: ** [[the xCachesize() page cache method]]
! 6130: ** ^(The xCachesize() method may be called at any time by SQLite to set the
! 6131: ** suggested maximum cache-size (number of pages stored by) the cache
! 6132: ** instance passed as the first argument. This is the value configured using
! 6133: ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
! 6134: ** parameter, the implementation is not required to do anything with this
! 6135: ** value; it is advisory only.
! 6136: **
! 6137: ** [[the xPagecount() page cache methods]]
! 6138: ** The xPagecount() method must return the number of pages currently
! 6139: ** stored in the cache, both pinned and unpinned.
! 6140: **
! 6141: ** [[the xFetch() page cache methods]]
! 6142: ** The xFetch() method locates a page in the cache and returns a pointer to
! 6143: ** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
! 6144: ** The pBuf element of the returned sqlite3_pcache_page object will be a
! 6145: ** pointer to a buffer of szPage bytes used to store the content of a
! 6146: ** single database page. The pExtra element of sqlite3_pcache_page will be
! 6147: ** a pointer to the szExtra bytes of extra storage that SQLite has requested
! 6148: ** for each entry in the page cache.
! 6149: **
! 6150: ** The page to be fetched is determined by the key. ^The minimum key value
! 6151: ** is 1. After it has been retrieved using xFetch, the page is considered
! 6152: ** to be "pinned".
! 6153: **
! 6154: ** If the requested page is already in the page cache, then the page cache
! 6155: ** implementation must return a pointer to the page buffer with its content
! 6156: ** intact. If the requested page is not already in the cache, then the
! 6157: ** cache implementation should use the value of the createFlag
! 6158: ** parameter to help it determined what action to take:
! 6159: **
! 6160: ** <table border=1 width=85% align=center>
! 6161: ** <tr><th> createFlag <th> Behaviour when page is not already in cache
! 6162: ** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
! 6163: ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
! 6164: ** Otherwise return NULL.
! 6165: ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
! 6166: ** NULL if allocating a new page is effectively impossible.
! 6167: ** </table>
! 6168: **
! 6169: ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
! 6170: ** will only use a createFlag of 2 after a prior call with a createFlag of 1
! 6171: ** failed.)^ In between the to xFetch() calls, SQLite may
! 6172: ** attempt to unpin one or more cache pages by spilling the content of
! 6173: ** pinned pages to disk and synching the operating system disk cache.
! 6174: **
! 6175: ** [[the xUnpin() page cache method]]
! 6176: ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
! 6177: ** as its second argument. If the third parameter, discard, is non-zero,
! 6178: ** then the page must be evicted from the cache.
! 6179: ** ^If the discard parameter is
! 6180: ** zero, then the page may be discarded or retained at the discretion of
! 6181: ** page cache implementation. ^The page cache implementation
! 6182: ** may choose to evict unpinned pages at any time.
! 6183: **
! 6184: ** The cache must not perform any reference counting. A single
! 6185: ** call to xUnpin() unpins the page regardless of the number of prior calls
! 6186: ** to xFetch().
! 6187: **
! 6188: ** [[the xRekey() page cache methods]]
! 6189: ** The xRekey() method is used to change the key value associated with the
! 6190: ** page passed as the second argument. If the cache
! 6191: ** previously contains an entry associated with newKey, it must be
! 6192: ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
! 6193: ** to be pinned.
! 6194: **
! 6195: ** When SQLite calls the xTruncate() method, the cache must discard all
! 6196: ** existing cache entries with page numbers (keys) greater than or equal
! 6197: ** to the value of the iLimit parameter passed to xTruncate(). If any
! 6198: ** of these pages are pinned, they are implicitly unpinned, meaning that
! 6199: ** they can be safely discarded.
! 6200: **
! 6201: ** [[the xDestroy() page cache method]]
! 6202: ** ^The xDestroy() method is used to delete a cache allocated by xCreate().
! 6203: ** All resources associated with the specified cache should be freed. ^After
! 6204: ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
! 6205: ** handle invalid, and will not use it with any other sqlite3_pcache_methods2
! 6206: ** functions.
! 6207: **
! 6208: ** [[the xShrink() page cache method]]
! 6209: ** ^SQLite invokes the xShrink() method when it wants the page cache to
! 6210: ** free up as much of heap memory as possible. The page cache implementation
! 6211: ** is not obligated to free any memory, but well-behaved implementations should
! 6212: ** do their best.
! 6213: */
! 6214: typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
! 6215: struct sqlite3_pcache_methods2 {
! 6216: int iVersion;
! 6217: void *pArg;
! 6218: int (*xInit)(void*);
! 6219: void (*xShutdown)(void*);
! 6220: sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
! 6221: void (*xCachesize)(sqlite3_pcache*, int nCachesize);
! 6222: int (*xPagecount)(sqlite3_pcache*);
! 6223: sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
! 6224: void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
! 6225: void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
! 6226: unsigned oldKey, unsigned newKey);
! 6227: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
! 6228: void (*xDestroy)(sqlite3_pcache*);
! 6229: void (*xShrink)(sqlite3_pcache*);
! 6230: };
! 6231:
! 6232: /*
! 6233: ** This is the obsolete pcache_methods object that has now been replaced
! 6234: ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
! 6235: ** retained in the header file for backwards compatibility only.
! 6236: */
! 6237: typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
! 6238: struct sqlite3_pcache_methods {
! 6239: void *pArg;
! 6240: int (*xInit)(void*);
! 6241: void (*xShutdown)(void*);
! 6242: sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
! 6243: void (*xCachesize)(sqlite3_pcache*, int nCachesize);
! 6244: int (*xPagecount)(sqlite3_pcache*);
! 6245: void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
! 6246: void (*xUnpin)(sqlite3_pcache*, void*, int discard);
! 6247: void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
! 6248: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
! 6249: void (*xDestroy)(sqlite3_pcache*);
! 6250: };
! 6251:
! 6252:
! 6253: /*
! 6254: ** CAPI3REF: Online Backup Object
! 6255: **
! 6256: ** The sqlite3_backup object records state information about an ongoing
! 6257: ** online backup operation. ^The sqlite3_backup object is created by
! 6258: ** a call to [sqlite3_backup_init()] and is destroyed by a call to
! 6259: ** [sqlite3_backup_finish()].
! 6260: **
! 6261: ** See Also: [Using the SQLite Online Backup API]
! 6262: */
! 6263: typedef struct sqlite3_backup sqlite3_backup;
! 6264:
! 6265: /*
! 6266: ** CAPI3REF: Online Backup API.
! 6267: **
! 6268: ** The backup API copies the content of one database into another.
! 6269: ** It is useful either for creating backups of databases or
! 6270: ** for copying in-memory databases to or from persistent files.
! 6271: **
! 6272: ** See Also: [Using the SQLite Online Backup API]
! 6273: **
! 6274: ** ^SQLite holds a write transaction open on the destination database file
! 6275: ** for the duration of the backup operation.
! 6276: ** ^The source database is read-locked only while it is being read;
! 6277: ** it is not locked continuously for the entire backup operation.
! 6278: ** ^Thus, the backup may be performed on a live source database without
! 6279: ** preventing other database connections from
! 6280: ** reading or writing to the source database while the backup is underway.
! 6281: **
! 6282: ** ^(To perform a backup operation:
! 6283: ** <ol>
! 6284: ** <li><b>sqlite3_backup_init()</b> is called once to initialize the
! 6285: ** backup,
! 6286: ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
! 6287: ** the data between the two databases, and finally
! 6288: ** <li><b>sqlite3_backup_finish()</b> is called to release all resources
! 6289: ** associated with the backup operation.
! 6290: ** </ol>)^
! 6291: ** There should be exactly one call to sqlite3_backup_finish() for each
! 6292: ** successful call to sqlite3_backup_init().
! 6293: **
! 6294: ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
! 6295: **
! 6296: ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
! 6297: ** [database connection] associated with the destination database
! 6298: ** and the database name, respectively.
! 6299: ** ^The database name is "main" for the main database, "temp" for the
! 6300: ** temporary database, or the name specified after the AS keyword in
! 6301: ** an [ATTACH] statement for an attached database.
! 6302: ** ^The S and M arguments passed to
! 6303: ** sqlite3_backup_init(D,N,S,M) identify the [database connection]
! 6304: ** and database name of the source database, respectively.
! 6305: ** ^The source and destination [database connections] (parameters S and D)
! 6306: ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
! 6307: ** an error.
! 6308: **
! 6309: ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
! 6310: ** returned and an error code and error message are stored in the
! 6311: ** destination [database connection] D.
! 6312: ** ^The error code and message for the failed call to sqlite3_backup_init()
! 6313: ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
! 6314: ** [sqlite3_errmsg16()] functions.
! 6315: ** ^A successful call to sqlite3_backup_init() returns a pointer to an
! 6316: ** [sqlite3_backup] object.
! 6317: ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
! 6318: ** sqlite3_backup_finish() functions to perform the specified backup
! 6319: ** operation.
! 6320: **
! 6321: ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
! 6322: **
! 6323: ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
! 6324: ** the source and destination databases specified by [sqlite3_backup] object B.
! 6325: ** ^If N is negative, all remaining source pages are copied.
! 6326: ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
! 6327: ** are still more pages to be copied, then the function returns [SQLITE_OK].
! 6328: ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
! 6329: ** from source to destination, then it returns [SQLITE_DONE].
! 6330: ** ^If an error occurs while running sqlite3_backup_step(B,N),
! 6331: ** then an [error code] is returned. ^As well as [SQLITE_OK] and
! 6332: ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
! 6333: ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
! 6334: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
! 6335: **
! 6336: ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
! 6337: ** <ol>
! 6338: ** <li> the destination database was opened read-only, or
! 6339: ** <li> the destination database is using write-ahead-log journaling
! 6340: ** and the destination and source page sizes differ, or
! 6341: ** <li> the destination database is an in-memory database and the
! 6342: ** destination and source page sizes differ.
! 6343: ** </ol>)^
! 6344: **
! 6345: ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
! 6346: ** the [sqlite3_busy_handler | busy-handler function]
! 6347: ** is invoked (if one is specified). ^If the
! 6348: ** busy-handler returns non-zero before the lock is available, then
! 6349: ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
! 6350: ** sqlite3_backup_step() can be retried later. ^If the source
! 6351: ** [database connection]
! 6352: ** is being used to write to the source database when sqlite3_backup_step()
! 6353: ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
! 6354: ** case the call to sqlite3_backup_step() can be retried later on. ^(If
! 6355: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
! 6356: ** [SQLITE_READONLY] is returned, then
! 6357: ** there is no point in retrying the call to sqlite3_backup_step(). These
! 6358: ** errors are considered fatal.)^ The application must accept
! 6359: ** that the backup operation has failed and pass the backup operation handle
! 6360: ** to the sqlite3_backup_finish() to release associated resources.
! 6361: **
! 6362: ** ^The first call to sqlite3_backup_step() obtains an exclusive lock
! 6363: ** on the destination file. ^The exclusive lock is not released until either
! 6364: ** sqlite3_backup_finish() is called or the backup operation is complete
! 6365: ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
! 6366: ** sqlite3_backup_step() obtains a [shared lock] on the source database that
! 6367: ** lasts for the duration of the sqlite3_backup_step() call.
! 6368: ** ^Because the source database is not locked between calls to
! 6369: ** sqlite3_backup_step(), the source database may be modified mid-way
! 6370: ** through the backup process. ^If the source database is modified by an
! 6371: ** external process or via a database connection other than the one being
! 6372: ** used by the backup operation, then the backup will be automatically
! 6373: ** restarted by the next call to sqlite3_backup_step(). ^If the source
! 6374: ** database is modified by the using the same database connection as is used
! 6375: ** by the backup operation, then the backup database is automatically
! 6376: ** updated at the same time.
! 6377: **
! 6378: ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
! 6379: **
! 6380: ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
! 6381: ** application wishes to abandon the backup operation, the application
! 6382: ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
! 6383: ** ^The sqlite3_backup_finish() interfaces releases all
! 6384: ** resources associated with the [sqlite3_backup] object.
! 6385: ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
! 6386: ** active write-transaction on the destination database is rolled back.
! 6387: ** The [sqlite3_backup] object is invalid
! 6388: ** and may not be used following a call to sqlite3_backup_finish().
! 6389: **
! 6390: ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
! 6391: ** sqlite3_backup_step() errors occurred, regardless or whether or not
! 6392: ** sqlite3_backup_step() completed.
! 6393: ** ^If an out-of-memory condition or IO error occurred during any prior
! 6394: ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
! 6395: ** sqlite3_backup_finish() returns the corresponding [error code].
! 6396: **
! 6397: ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
! 6398: ** is not a permanent error and does not affect the return value of
! 6399: ** sqlite3_backup_finish().
! 6400: **
! 6401: ** [[sqlite3_backup__remaining()]] [[sqlite3_backup_pagecount()]]
! 6402: ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
! 6403: **
! 6404: ** ^Each call to sqlite3_backup_step() sets two values inside
! 6405: ** the [sqlite3_backup] object: the number of pages still to be backed
! 6406: ** up and the total number of pages in the source database file.
! 6407: ** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
! 6408: ** retrieve these two values, respectively.
! 6409: **
! 6410: ** ^The values returned by these functions are only updated by
! 6411: ** sqlite3_backup_step(). ^If the source database is modified during a backup
! 6412: ** operation, then the values are not updated to account for any extra
! 6413: ** pages that need to be updated or the size of the source database file
! 6414: ** changing.
! 6415: **
! 6416: ** <b>Concurrent Usage of Database Handles</b>
! 6417: **
! 6418: ** ^The source [database connection] may be used by the application for other
! 6419: ** purposes while a backup operation is underway or being initialized.
! 6420: ** ^If SQLite is compiled and configured to support threadsafe database
! 6421: ** connections, then the source database connection may be used concurrently
! 6422: ** from within other threads.
! 6423: **
! 6424: ** However, the application must guarantee that the destination
! 6425: ** [database connection] is not passed to any other API (by any thread) after
! 6426: ** sqlite3_backup_init() is called and before the corresponding call to
! 6427: ** sqlite3_backup_finish(). SQLite does not currently check to see
! 6428: ** if the application incorrectly accesses the destination [database connection]
! 6429: ** and so no error code is reported, but the operations may malfunction
! 6430: ** nevertheless. Use of the destination database connection while a
! 6431: ** backup is in progress might also also cause a mutex deadlock.
! 6432: **
! 6433: ** If running in [shared cache mode], the application must
! 6434: ** guarantee that the shared cache used by the destination database
! 6435: ** is not accessed while the backup is running. In practice this means
! 6436: ** that the application must guarantee that the disk file being
! 6437: ** backed up to is not accessed by any connection within the process,
! 6438: ** not just the specific connection that was passed to sqlite3_backup_init().
! 6439: **
! 6440: ** The [sqlite3_backup] object itself is partially threadsafe. Multiple
! 6441: ** threads may safely make multiple concurrent calls to sqlite3_backup_step().
! 6442: ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
! 6443: ** APIs are not strictly speaking threadsafe. If they are invoked at the
! 6444: ** same time as another thread is invoking sqlite3_backup_step() it is
! 6445: ** possible that they return invalid values.
! 6446: */
! 6447: sqlite3_backup *sqlite3_backup_init(
! 6448: sqlite3 *pDest, /* Destination database handle */
! 6449: const char *zDestName, /* Destination database name */
! 6450: sqlite3 *pSource, /* Source database handle */
! 6451: const char *zSourceName /* Source database name */
! 6452: );
! 6453: int sqlite3_backup_step(sqlite3_backup *p, int nPage);
! 6454: int sqlite3_backup_finish(sqlite3_backup *p);
! 6455: int sqlite3_backup_remaining(sqlite3_backup *p);
! 6456: int sqlite3_backup_pagecount(sqlite3_backup *p);
! 6457:
! 6458: /*
! 6459: ** CAPI3REF: Unlock Notification
! 6460: **
! 6461: ** ^When running in shared-cache mode, a database operation may fail with
! 6462: ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
! 6463: ** individual tables within the shared-cache cannot be obtained. See
! 6464: ** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
! 6465: ** ^This API may be used to register a callback that SQLite will invoke
! 6466: ** when the connection currently holding the required lock relinquishes it.
! 6467: ** ^This API is only available if the library was compiled with the
! 6468: ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
! 6469: **
! 6470: ** See Also: [Using the SQLite Unlock Notification Feature].
! 6471: **
! 6472: ** ^Shared-cache locks are released when a database connection concludes
! 6473: ** its current transaction, either by committing it or rolling it back.
! 6474: **
! 6475: ** ^When a connection (known as the blocked connection) fails to obtain a
! 6476: ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
! 6477: ** identity of the database connection (the blocking connection) that
! 6478: ** has locked the required resource is stored internally. ^After an
! 6479: ** application receives an SQLITE_LOCKED error, it may call the
! 6480: ** sqlite3_unlock_notify() method with the blocked connection handle as
! 6481: ** the first argument to register for a callback that will be invoked
! 6482: ** when the blocking connections current transaction is concluded. ^The
! 6483: ** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
! 6484: ** call that concludes the blocking connections transaction.
! 6485: **
! 6486: ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
! 6487: ** there is a chance that the blocking connection will have already
! 6488: ** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
! 6489: ** If this happens, then the specified callback is invoked immediately,
! 6490: ** from within the call to sqlite3_unlock_notify().)^
! 6491: **
! 6492: ** ^If the blocked connection is attempting to obtain a write-lock on a
! 6493: ** shared-cache table, and more than one other connection currently holds
! 6494: ** a read-lock on the same table, then SQLite arbitrarily selects one of
! 6495: ** the other connections to use as the blocking connection.
! 6496: **
! 6497: ** ^(There may be at most one unlock-notify callback registered by a
! 6498: ** blocked connection. If sqlite3_unlock_notify() is called when the
! 6499: ** blocked connection already has a registered unlock-notify callback,
! 6500: ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
! 6501: ** called with a NULL pointer as its second argument, then any existing
! 6502: ** unlock-notify callback is canceled. ^The blocked connections
! 6503: ** unlock-notify callback may also be canceled by closing the blocked
! 6504: ** connection using [sqlite3_close()].
! 6505: **
! 6506: ** The unlock-notify callback is not reentrant. If an application invokes
! 6507: ** any sqlite3_xxx API functions from within an unlock-notify callback, a
! 6508: ** crash or deadlock may be the result.
! 6509: **
! 6510: ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
! 6511: ** returns SQLITE_OK.
! 6512: **
! 6513: ** <b>Callback Invocation Details</b>
! 6514: **
! 6515: ** When an unlock-notify callback is registered, the application provides a
! 6516: ** single void* pointer that is passed to the callback when it is invoked.
! 6517: ** However, the signature of the callback function allows SQLite to pass
! 6518: ** it an array of void* context pointers. The first argument passed to
! 6519: ** an unlock-notify callback is a pointer to an array of void* pointers,
! 6520: ** and the second is the number of entries in the array.
! 6521: **
! 6522: ** When a blocking connections transaction is concluded, there may be
! 6523: ** more than one blocked connection that has registered for an unlock-notify
! 6524: ** callback. ^If two or more such blocked connections have specified the
! 6525: ** same callback function, then instead of invoking the callback function
! 6526: ** multiple times, it is invoked once with the set of void* context pointers
! 6527: ** specified by the blocked connections bundled together into an array.
! 6528: ** This gives the application an opportunity to prioritize any actions
! 6529: ** related to the set of unblocked database connections.
! 6530: **
! 6531: ** <b>Deadlock Detection</b>
! 6532: **
! 6533: ** Assuming that after registering for an unlock-notify callback a
! 6534: ** database waits for the callback to be issued before taking any further
! 6535: ** action (a reasonable assumption), then using this API may cause the
! 6536: ** application to deadlock. For example, if connection X is waiting for
! 6537: ** connection Y's transaction to be concluded, and similarly connection
! 6538: ** Y is waiting on connection X's transaction, then neither connection
! 6539: ** will proceed and the system may remain deadlocked indefinitely.
! 6540: **
! 6541: ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
! 6542: ** detection. ^If a given call to sqlite3_unlock_notify() would put the
! 6543: ** system in a deadlocked state, then SQLITE_LOCKED is returned and no
! 6544: ** unlock-notify callback is registered. The system is said to be in
! 6545: ** a deadlocked state if connection A has registered for an unlock-notify
! 6546: ** callback on the conclusion of connection B's transaction, and connection
! 6547: ** B has itself registered for an unlock-notify callback when connection
! 6548: ** A's transaction is concluded. ^Indirect deadlock is also detected, so
! 6549: ** the system is also considered to be deadlocked if connection B has
! 6550: ** registered for an unlock-notify callback on the conclusion of connection
! 6551: ** C's transaction, where connection C is waiting on connection A. ^Any
! 6552: ** number of levels of indirection are allowed.
! 6553: **
! 6554: ** <b>The "DROP TABLE" Exception</b>
! 6555: **
! 6556: ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
! 6557: ** always appropriate to call sqlite3_unlock_notify(). There is however,
! 6558: ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
! 6559: ** SQLite checks if there are any currently executing SELECT statements
! 6560: ** that belong to the same connection. If there are, SQLITE_LOCKED is
! 6561: ** returned. In this case there is no "blocking connection", so invoking
! 6562: ** sqlite3_unlock_notify() results in the unlock-notify callback being
! 6563: ** invoked immediately. If the application then re-attempts the "DROP TABLE"
! 6564: ** or "DROP INDEX" query, an infinite loop might be the result.
! 6565: **
! 6566: ** One way around this problem is to check the extended error code returned
! 6567: ** by an sqlite3_step() call. ^(If there is a blocking connection, then the
! 6568: ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
! 6569: ** the special "DROP TABLE/INDEX" case, the extended error code is just
! 6570: ** SQLITE_LOCKED.)^
! 6571: */
! 6572: int sqlite3_unlock_notify(
! 6573: sqlite3 *pBlocked, /* Waiting connection */
! 6574: void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
! 6575: void *pNotifyArg /* Argument to pass to xNotify */
! 6576: );
! 6577:
! 6578:
! 6579: /*
! 6580: ** CAPI3REF: String Comparison
! 6581: **
! 6582: ** ^The [sqlite3_strnicmp()] API allows applications and extensions to
! 6583: ** compare the contents of two buffers containing UTF-8 strings in a
! 6584: ** case-independent fashion, using the same definition of case independence
! 6585: ** that SQLite uses internally when comparing identifiers.
! 6586: */
! 6587: int sqlite3_strnicmp(const char *, const char *, int);
! 6588:
! 6589: /*
! 6590: ** CAPI3REF: Error Logging Interface
! 6591: **
! 6592: ** ^The [sqlite3_log()] interface writes a message into the error log
! 6593: ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
! 6594: ** ^If logging is enabled, the zFormat string and subsequent arguments are
! 6595: ** used with [sqlite3_snprintf()] to generate the final output string.
! 6596: **
! 6597: ** The sqlite3_log() interface is intended for use by extensions such as
! 6598: ** virtual tables, collating functions, and SQL functions. While there is
! 6599: ** nothing to prevent an application from calling sqlite3_log(), doing so
! 6600: ** is considered bad form.
! 6601: **
! 6602: ** The zFormat string must not be NULL.
! 6603: **
! 6604: ** To avoid deadlocks and other threading problems, the sqlite3_log() routine
! 6605: ** will not use dynamically allocated memory. The log message is stored in
! 6606: ** a fixed-length buffer on the stack. If the log message is longer than
! 6607: ** a few hundred characters, it will be truncated to the length of the
! 6608: ** buffer.
! 6609: */
! 6610: void sqlite3_log(int iErrCode, const char *zFormat, ...);
! 6611:
! 6612: /*
! 6613: ** CAPI3REF: Write-Ahead Log Commit Hook
! 6614: **
! 6615: ** ^The [sqlite3_wal_hook()] function is used to register a callback that
! 6616: ** will be invoked each time a database connection commits data to a
! 6617: ** [write-ahead log] (i.e. whenever a transaction is committed in
! 6618: ** [journal_mode | journal_mode=WAL mode]).
! 6619: **
! 6620: ** ^The callback is invoked by SQLite after the commit has taken place and
! 6621: ** the associated write-lock on the database released, so the implementation
! 6622: ** may read, write or [checkpoint] the database as required.
! 6623: **
! 6624: ** ^The first parameter passed to the callback function when it is invoked
! 6625: ** is a copy of the third parameter passed to sqlite3_wal_hook() when
! 6626: ** registering the callback. ^The second is a copy of the database handle.
! 6627: ** ^The third parameter is the name of the database that was written to -
! 6628: ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
! 6629: ** is the number of pages currently in the write-ahead log file,
! 6630: ** including those that were just committed.
! 6631: **
! 6632: ** The callback function should normally return [SQLITE_OK]. ^If an error
! 6633: ** code is returned, that error will propagate back up through the
! 6634: ** SQLite code base to cause the statement that provoked the callback
! 6635: ** to report an error, though the commit will have still occurred. If the
! 6636: ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
! 6637: ** that does not correspond to any valid SQLite error code, the results
! 6638: ** are undefined.
! 6639: **
! 6640: ** A single database handle may have at most a single write-ahead log callback
! 6641: ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
! 6642: ** previously registered write-ahead log callback. ^Note that the
! 6643: ** [sqlite3_wal_autocheckpoint()] interface and the
! 6644: ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
! 6645: ** those overwrite any prior [sqlite3_wal_hook()] settings.
! 6646: */
! 6647: void *sqlite3_wal_hook(
! 6648: sqlite3*,
! 6649: int(*)(void *,sqlite3*,const char*,int),
! 6650: void*
! 6651: );
! 6652:
! 6653: /*
! 6654: ** CAPI3REF: Configure an auto-checkpoint
! 6655: **
! 6656: ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
! 6657: ** [sqlite3_wal_hook()] that causes any database on [database connection] D
! 6658: ** to automatically [checkpoint]
! 6659: ** after committing a transaction if there are N or
! 6660: ** more frames in the [write-ahead log] file. ^Passing zero or
! 6661: ** a negative value as the nFrame parameter disables automatic
! 6662: ** checkpoints entirely.
! 6663: **
! 6664: ** ^The callback registered by this function replaces any existing callback
! 6665: ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
! 6666: ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
! 6667: ** configured by this function.
! 6668: **
! 6669: ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
! 6670: ** from SQL.
! 6671: **
! 6672: ** ^Every new [database connection] defaults to having the auto-checkpoint
! 6673: ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
! 6674: ** pages. The use of this interface
! 6675: ** is only necessary if the default setting is found to be suboptimal
! 6676: ** for a particular application.
! 6677: */
! 6678: int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
! 6679:
! 6680: /*
! 6681: ** CAPI3REF: Checkpoint a database
! 6682: **
! 6683: ** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X
! 6684: ** on [database connection] D to be [checkpointed]. ^If X is NULL or an
! 6685: ** empty string, then a checkpoint is run on all databases of
! 6686: ** connection D. ^If the database connection D is not in
! 6687: ** [WAL | write-ahead log mode] then this interface is a harmless no-op.
! 6688: **
! 6689: ** ^The [wal_checkpoint pragma] can be used to invoke this interface
! 6690: ** from SQL. ^The [sqlite3_wal_autocheckpoint()] interface and the
! 6691: ** [wal_autocheckpoint pragma] can be used to cause this interface to be
! 6692: ** run whenever the WAL reaches a certain size threshold.
! 6693: **
! 6694: ** See also: [sqlite3_wal_checkpoint_v2()]
! 6695: */
! 6696: int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
! 6697:
! 6698: /*
! 6699: ** CAPI3REF: Checkpoint a database
! 6700: **
! 6701: ** Run a checkpoint operation on WAL database zDb attached to database
! 6702: ** handle db. The specific operation is determined by the value of the
! 6703: ** eMode parameter:
! 6704: **
! 6705: ** <dl>
! 6706: ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
! 6707: ** Checkpoint as many frames as possible without waiting for any database
! 6708: ** readers or writers to finish. Sync the db file if all frames in the log
! 6709: ** are checkpointed. This mode is the same as calling
! 6710: ** sqlite3_wal_checkpoint(). The busy-handler callback is never invoked.
! 6711: **
! 6712: ** <dt>SQLITE_CHECKPOINT_FULL<dd>
! 6713: ** This mode blocks (calls the busy-handler callback) until there is no
! 6714: ** database writer and all readers are reading from the most recent database
! 6715: ** snapshot. It then checkpoints all frames in the log file and syncs the
! 6716: ** database file. This call blocks database writers while it is running,
! 6717: ** but not database readers.
! 6718: **
! 6719: ** <dt>SQLITE_CHECKPOINT_RESTART<dd>
! 6720: ** This mode works the same way as SQLITE_CHECKPOINT_FULL, except after
! 6721: ** checkpointing the log file it blocks (calls the busy-handler callback)
! 6722: ** until all readers are reading from the database file only. This ensures
! 6723: ** that the next client to write to the database file restarts the log file
! 6724: ** from the beginning. This call blocks database writers while it is running,
! 6725: ** but not database readers.
! 6726: ** </dl>
! 6727: **
! 6728: ** If pnLog is not NULL, then *pnLog is set to the total number of frames in
! 6729: ** the log file before returning. If pnCkpt is not NULL, then *pnCkpt is set to
! 6730: ** the total number of checkpointed frames (including any that were already
! 6731: ** checkpointed when this function is called). *pnLog and *pnCkpt may be
! 6732: ** populated even if sqlite3_wal_checkpoint_v2() returns other than SQLITE_OK.
! 6733: ** If no values are available because of an error, they are both set to -1
! 6734: ** before returning to communicate this to the caller.
! 6735: **
! 6736: ** All calls obtain an exclusive "checkpoint" lock on the database file. If
! 6737: ** any other process is running a checkpoint operation at the same time, the
! 6738: ** lock cannot be obtained and SQLITE_BUSY is returned. Even if there is a
! 6739: ** busy-handler configured, it will not be invoked in this case.
! 6740: **
! 6741: ** The SQLITE_CHECKPOINT_FULL and RESTART modes also obtain the exclusive
! 6742: ** "writer" lock on the database file. If the writer lock cannot be obtained
! 6743: ** immediately, and a busy-handler is configured, it is invoked and the writer
! 6744: ** lock retried until either the busy-handler returns 0 or the lock is
! 6745: ** successfully obtained. The busy-handler is also invoked while waiting for
! 6746: ** database readers as described above. If the busy-handler returns 0 before
! 6747: ** the writer lock is obtained or while waiting for database readers, the
! 6748: ** checkpoint operation proceeds from that point in the same way as
! 6749: ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
! 6750: ** without blocking any further. SQLITE_BUSY is returned in this case.
! 6751: **
! 6752: ** If parameter zDb is NULL or points to a zero length string, then the
! 6753: ** specified operation is attempted on all WAL databases. In this case the
! 6754: ** values written to output parameters *pnLog and *pnCkpt are undefined. If
! 6755: ** an SQLITE_BUSY error is encountered when processing one or more of the
! 6756: ** attached WAL databases, the operation is still attempted on any remaining
! 6757: ** attached databases and SQLITE_BUSY is returned to the caller. If any other
! 6758: ** error occurs while processing an attached database, processing is abandoned
! 6759: ** and the error code returned to the caller immediately. If no error
! 6760: ** (SQLITE_BUSY or otherwise) is encountered while processing the attached
! 6761: ** databases, SQLITE_OK is returned.
! 6762: **
! 6763: ** If database zDb is the name of an attached database that is not in WAL
! 6764: ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. If
! 6765: ** zDb is not NULL (or a zero length string) and is not the name of any
! 6766: ** attached database, SQLITE_ERROR is returned to the caller.
! 6767: */
! 6768: int sqlite3_wal_checkpoint_v2(
! 6769: sqlite3 *db, /* Database handle */
! 6770: const char *zDb, /* Name of attached database (or NULL) */
! 6771: int eMode, /* SQLITE_CHECKPOINT_* value */
! 6772: int *pnLog, /* OUT: Size of WAL log in frames */
! 6773: int *pnCkpt /* OUT: Total number of frames checkpointed */
! 6774: );
! 6775:
! 6776: /*
! 6777: ** CAPI3REF: Checkpoint operation parameters
! 6778: **
! 6779: ** These constants can be used as the 3rd parameter to
! 6780: ** [sqlite3_wal_checkpoint_v2()]. See the [sqlite3_wal_checkpoint_v2()]
! 6781: ** documentation for additional information about the meaning and use of
! 6782: ** each of these values.
! 6783: */
! 6784: #define SQLITE_CHECKPOINT_PASSIVE 0
! 6785: #define SQLITE_CHECKPOINT_FULL 1
! 6786: #define SQLITE_CHECKPOINT_RESTART 2
! 6787:
! 6788: /*
! 6789: ** CAPI3REF: Virtual Table Interface Configuration
! 6790: **
! 6791: ** This function may be called by either the [xConnect] or [xCreate] method
! 6792: ** of a [virtual table] implementation to configure
! 6793: ** various facets of the virtual table interface.
! 6794: **
! 6795: ** If this interface is invoked outside the context of an xConnect or
! 6796: ** xCreate virtual table method then the behavior is undefined.
! 6797: **
! 6798: ** At present, there is only one option that may be configured using
! 6799: ** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options
! 6800: ** may be added in the future.
! 6801: */
! 6802: int sqlite3_vtab_config(sqlite3*, int op, ...);
! 6803:
! 6804: /*
! 6805: ** CAPI3REF: Virtual Table Configuration Options
! 6806: **
! 6807: ** These macros define the various options to the
! 6808: ** [sqlite3_vtab_config()] interface that [virtual table] implementations
! 6809: ** can use to customize and optimize their behavior.
! 6810: **
! 6811: ** <dl>
! 6812: ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT
! 6813: ** <dd>Calls of the form
! 6814: ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
! 6815: ** where X is an integer. If X is zero, then the [virtual table] whose
! 6816: ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
! 6817: ** support constraints. In this configuration (which is the default) if
! 6818: ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
! 6819: ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
! 6820: ** specified as part of the users SQL statement, regardless of the actual
! 6821: ** ON CONFLICT mode specified.
! 6822: **
! 6823: ** If X is non-zero, then the virtual table implementation guarantees
! 6824: ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
! 6825: ** any modifications to internal or persistent data structures have been made.
! 6826: ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
! 6827: ** is able to roll back a statement or database transaction, and abandon
! 6828: ** or continue processing the current SQL statement as appropriate.
! 6829: ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
! 6830: ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
! 6831: ** had been ABORT.
! 6832: **
! 6833: ** Virtual table implementations that are required to handle OR REPLACE
! 6834: ** must do so within the [xUpdate] method. If a call to the
! 6835: ** [sqlite3_vtab_on_conflict()] function indicates that the current ON
! 6836: ** CONFLICT policy is REPLACE, the virtual table implementation should
! 6837: ** silently replace the appropriate rows within the xUpdate callback and
! 6838: ** return SQLITE_OK. Or, if this is not possible, it may return
! 6839: ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
! 6840: ** constraint handling.
! 6841: ** </dl>
! 6842: */
! 6843: #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
! 6844:
! 6845: /*
! 6846: ** CAPI3REF: Determine The Virtual Table Conflict Policy
! 6847: **
! 6848: ** This function may only be called from within a call to the [xUpdate] method
! 6849: ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
! 6850: ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
! 6851: ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
! 6852: ** of the SQL statement that triggered the call to the [xUpdate] method of the
! 6853: ** [virtual table].
! 6854: */
! 6855: int sqlite3_vtab_on_conflict(sqlite3 *);
! 6856:
! 6857: /*
! 6858: ** CAPI3REF: Conflict resolution modes
! 6859: **
! 6860: ** These constants are returned by [sqlite3_vtab_on_conflict()] to
! 6861: ** inform a [virtual table] implementation what the [ON CONFLICT] mode
! 6862: ** is for the SQL statement being evaluated.
! 6863: **
! 6864: ** Note that the [SQLITE_IGNORE] constant is also used as a potential
! 6865: ** return value from the [sqlite3_set_authorizer()] callback and that
! 6866: ** [SQLITE_ABORT] is also a [result code].
! 6867: */
! 6868: #define SQLITE_ROLLBACK 1
! 6869: /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
! 6870: #define SQLITE_FAIL 3
! 6871: /* #define SQLITE_ABORT 4 // Also an error code */
! 6872: #define SQLITE_REPLACE 5
! 6873:
! 6874:
! 6875:
! 6876: /*
! 6877: ** Undo the hack that converts floating point types to integer for
! 6878: ** builds on processors without floating point support.
! 6879: */
! 6880: #ifdef SQLITE_OMIT_FLOATING_POINT
! 6881: # undef double
! 6882: #endif
! 6883:
! 6884: #ifdef __cplusplus
! 6885: } /* End of the 'extern "C"' block */
! 6886: #endif
! 6887: #endif
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