Annotation of elwix/files/sqlite/dist/sqlite3.h, revision 1.1.2.1
1.1.2.1 ! 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: #ifndef SQLITE_API
! 53: # define SQLITE_API
! 54: #endif
! 55:
! 56:
! 57: /*
! 58: ** These no-op macros are used in front of interfaces to mark those
! 59: ** interfaces as either deprecated or experimental. New applications
! 60: ** should not use deprecated interfaces - they are support for backwards
! 61: ** compatibility only. Application writers should be aware that
! 62: ** experimental interfaces are subject to change in point releases.
! 63: **
! 64: ** These macros used to resolve to various kinds of compiler magic that
! 65: ** would generate warning messages when they were used. But that
! 66: ** compiler magic ended up generating such a flurry of bug reports
! 67: ** that we have taken it all out and gone back to using simple
! 68: ** noop macros.
! 69: */
! 70: #define SQLITE_DEPRECATED
! 71: #define SQLITE_EXPERIMENTAL
! 72:
! 73: /*
! 74: ** Ensure these symbols were not defined by some previous header file.
! 75: */
! 76: #ifdef SQLITE_VERSION
! 77: # undef SQLITE_VERSION
! 78: #endif
! 79: #ifdef SQLITE_VERSION_NUMBER
! 80: # undef SQLITE_VERSION_NUMBER
! 81: #endif
! 82:
! 83: /*
! 84: ** CAPI3REF: Compile-Time Library Version Numbers
! 85: **
! 86: ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header
! 87: ** evaluates to a string literal that is the SQLite version in the
! 88: ** format "X.Y.Z" where X is the major version number (always 3 for
! 89: ** SQLite3) and Y is the minor version number and Z is the release number.)^
! 90: ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer
! 91: ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same
! 92: ** numbers used in [SQLITE_VERSION].)^
! 93: ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also
! 94: ** be larger than the release from which it is derived. Either Y will
! 95: ** be held constant and Z will be incremented or else Y will be incremented
! 96: ** and Z will be reset to zero.
! 97: **
! 98: ** Since version 3.6.18, SQLite source code has been stored in the
! 99: ** <a href="http://www.fossil-scm.org/">Fossil configuration management
! 100: ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to
! 101: ** a string which identifies a particular check-in of SQLite
! 102: ** within its configuration management system. ^The SQLITE_SOURCE_ID
! 103: ** string contains the date and time of the check-in (UTC) and an SHA1
! 104: ** hash of the entire source tree.
! 105: **
! 106: ** See also: [sqlite3_libversion()],
! 107: ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
! 108: ** [sqlite_version()] and [sqlite_source_id()].
! 109: */
! 110: #define SQLITE_VERSION "3.7.10"
! 111: #define SQLITE_VERSION_NUMBER 3007010
! 112: #define SQLITE_SOURCE_ID "2012-01-16 13:28:40 ebd01a8deffb5024a5d7494eef800d2366d97204"
! 113:
! 114: /*
! 115: ** CAPI3REF: Run-Time Library Version Numbers
! 116: ** KEYWORDS: sqlite3_version, sqlite3_sourceid
! 117: **
! 118: ** These interfaces provide the same information as the [SQLITE_VERSION],
! 119: ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros
! 120: ** but are associated with the library instead of the header file. ^(Cautious
! 121: ** programmers might include assert() statements in their application to
! 122: ** verify that values returned by these interfaces match the macros in
! 123: ** the header, and thus insure that the application is
! 124: ** compiled with matching library and header files.
! 125: **
! 126: ** <blockquote><pre>
! 127: ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
! 128: ** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );
! 129: ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
! 130: ** </pre></blockquote>)^
! 131: **
! 132: ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]
! 133: ** macro. ^The sqlite3_libversion() function returns a pointer to the
! 134: ** to the sqlite3_version[] string constant. The sqlite3_libversion()
! 135: ** function is provided for use in DLLs since DLL users usually do not have
! 136: ** direct access to string constants within the DLL. ^The
! 137: ** sqlite3_libversion_number() function returns an integer equal to
! 138: ** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns
! 139: ** a pointer to a string constant whose value is the same as the
! 140: ** [SQLITE_SOURCE_ID] C preprocessor macro.
! 141: **
! 142: ** See also: [sqlite_version()] and [sqlite_source_id()].
! 143: */
! 144: SQLITE_API SQLITE_EXTERN const char sqlite3_version[];
! 145: SQLITE_API const char *sqlite3_libversion(void);
! 146: SQLITE_API const char *sqlite3_sourceid(void);
! 147: SQLITE_API int sqlite3_libversion_number(void);
! 148:
! 149: /*
! 150: ** CAPI3REF: Run-Time Library Compilation Options Diagnostics
! 151: **
! 152: ** ^The sqlite3_compileoption_used() function returns 0 or 1
! 153: ** indicating whether the specified option was defined at
! 154: ** compile time. ^The SQLITE_ prefix may be omitted from the
! 155: ** option name passed to sqlite3_compileoption_used().
! 156: **
! 157: ** ^The sqlite3_compileoption_get() function allows iterating
! 158: ** over the list of options that were defined at compile time by
! 159: ** returning the N-th compile time option string. ^If N is out of range,
! 160: ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_
! 161: ** prefix is omitted from any strings returned by
! 162: ** sqlite3_compileoption_get().
! 163: **
! 164: ** ^Support for the diagnostic functions sqlite3_compileoption_used()
! 165: ** and sqlite3_compileoption_get() may be omitted by specifying the
! 166: ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.
! 167: **
! 168: ** See also: SQL functions [sqlite_compileoption_used()] and
! 169: ** [sqlite_compileoption_get()] and the [compile_options pragma].
! 170: */
! 171: #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
! 172: SQLITE_API int sqlite3_compileoption_used(const char *zOptName);
! 173: SQLITE_API const char *sqlite3_compileoption_get(int N);
! 174: #endif
! 175:
! 176: /*
! 177: ** CAPI3REF: Test To See If The Library Is Threadsafe
! 178: **
! 179: ** ^The sqlite3_threadsafe() function returns zero if and only if
! 180: ** SQLite was compiled with mutexing code omitted due to the
! 181: ** [SQLITE_THREADSAFE] compile-time option being set to 0.
! 182: **
! 183: ** SQLite can be compiled with or without mutexes. When
! 184: ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes
! 185: ** are enabled and SQLite is threadsafe. When the
! 186: ** [SQLITE_THREADSAFE] macro is 0,
! 187: ** the mutexes are omitted. Without the mutexes, it is not safe
! 188: ** to use SQLite concurrently from more than one thread.
! 189: **
! 190: ** Enabling mutexes incurs a measurable performance penalty.
! 191: ** So if speed is of utmost importance, it makes sense to disable
! 192: ** the mutexes. But for maximum safety, mutexes should be enabled.
! 193: ** ^The default behavior is for mutexes to be enabled.
! 194: **
! 195: ** This interface can be used by an application to make sure that the
! 196: ** version of SQLite that it is linking against was compiled with
! 197: ** the desired setting of the [SQLITE_THREADSAFE] macro.
! 198: **
! 199: ** This interface only reports on the compile-time mutex setting
! 200: ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with
! 201: ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but
! 202: ** can be fully or partially disabled using a call to [sqlite3_config()]
! 203: ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],
! 204: ** or [SQLITE_CONFIG_MUTEX]. ^(The return value of the
! 205: ** sqlite3_threadsafe() function shows only the compile-time setting of
! 206: ** thread safety, not any run-time changes to that setting made by
! 207: ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()
! 208: ** is unchanged by calls to sqlite3_config().)^
! 209: **
! 210: ** See the [threading mode] documentation for additional information.
! 211: */
! 212: SQLITE_API int sqlite3_threadsafe(void);
! 213:
! 214: /*
! 215: ** CAPI3REF: Database Connection Handle
! 216: ** KEYWORDS: {database connection} {database connections}
! 217: **
! 218: ** Each open SQLite database is represented by a pointer to an instance of
! 219: ** the opaque structure named "sqlite3". It is useful to think of an sqlite3
! 220: ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and
! 221: ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
! 222: ** is its destructor. There are many other interfaces (such as
! 223: ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
! 224: ** [sqlite3_busy_timeout()] to name but three) that are methods on an
! 225: ** sqlite3 object.
! 226: */
! 227: typedef struct sqlite3 sqlite3;
! 228:
! 229: /*
! 230: ** CAPI3REF: 64-Bit Integer Types
! 231: ** KEYWORDS: sqlite_int64 sqlite_uint64
! 232: **
! 233: ** Because there is no cross-platform way to specify 64-bit integer types
! 234: ** SQLite includes typedefs for 64-bit signed and unsigned integers.
! 235: **
! 236: ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.
! 237: ** The sqlite_int64 and sqlite_uint64 types are supported for backwards
! 238: ** compatibility only.
! 239: **
! 240: ** ^The sqlite3_int64 and sqlite_int64 types can store integer values
! 241: ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The
! 242: ** sqlite3_uint64 and sqlite_uint64 types can store integer values
! 243: ** between 0 and +18446744073709551615 inclusive.
! 244: */
! 245: #ifdef SQLITE_INT64_TYPE
! 246: typedef SQLITE_INT64_TYPE sqlite_int64;
! 247: typedef unsigned SQLITE_INT64_TYPE sqlite_uint64;
! 248: #elif defined(_MSC_VER) || defined(__BORLANDC__)
! 249: typedef __int64 sqlite_int64;
! 250: typedef unsigned __int64 sqlite_uint64;
! 251: #else
! 252: typedef long long int sqlite_int64;
! 253: typedef unsigned long long int sqlite_uint64;
! 254: #endif
! 255: typedef sqlite_int64 sqlite3_int64;
! 256: typedef sqlite_uint64 sqlite3_uint64;
! 257:
! 258: /*
! 259: ** If compiling for a processor that lacks floating point support,
! 260: ** substitute integer for floating-point.
! 261: */
! 262: #ifdef SQLITE_OMIT_FLOATING_POINT
! 263: # define double sqlite3_int64
! 264: #endif
! 265:
! 266: /*
! 267: ** CAPI3REF: Closing A Database Connection
! 268: **
! 269: ** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
! 270: ** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
! 271: ** successfully destroyed and all associated resources are deallocated.
! 272: **
! 273: ** Applications must [sqlite3_finalize | finalize] all [prepared statements]
! 274: ** and [sqlite3_blob_close | close] all [BLOB handles] associated with
! 275: ** the [sqlite3] object prior to attempting to close the object. ^If
! 276: ** sqlite3_close() is called on a [database connection] that still has
! 277: ** outstanding [prepared statements] or [BLOB handles], then it returns
! 278: ** SQLITE_BUSY.
! 279: **
! 280: ** ^If [sqlite3_close()] is invoked while a transaction is open,
! 281: ** the transaction is automatically rolled back.
! 282: **
! 283: ** The C parameter to [sqlite3_close(C)] must be either a NULL
! 284: ** pointer or an [sqlite3] object pointer obtained
! 285: ** from [sqlite3_open()], [sqlite3_open16()], or
! 286: ** [sqlite3_open_v2()], and not previously closed.
! 287: ** ^Calling sqlite3_close() with a NULL pointer argument is a
! 288: ** harmless no-op.
! 289: */
! 290: SQLITE_API int sqlite3_close(sqlite3 *);
! 291:
! 292: /*
! 293: ** The type for a callback function.
! 294: ** This is legacy and deprecated. It is included for historical
! 295: ** compatibility and is not documented.
! 296: */
! 297: typedef int (*sqlite3_callback)(void*,int,char**, char**);
! 298:
! 299: /*
! 300: ** CAPI3REF: One-Step Query Execution Interface
! 301: **
! 302: ** The sqlite3_exec() interface is a convenience wrapper around
! 303: ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],
! 304: ** that allows an application to run multiple statements of SQL
! 305: ** without having to use a lot of C code.
! 306: **
! 307: ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,
! 308: ** semicolon-separate SQL statements passed into its 2nd argument,
! 309: ** in the context of the [database connection] passed in as its 1st
! 310: ** argument. ^If the callback function of the 3rd argument to
! 311: ** sqlite3_exec() is not NULL, then it is invoked for each result row
! 312: ** coming out of the evaluated SQL statements. ^The 4th argument to
! 313: ** sqlite3_exec() is relayed through to the 1st argument of each
! 314: ** callback invocation. ^If the callback pointer to sqlite3_exec()
! 315: ** is NULL, then no callback is ever invoked and result rows are
! 316: ** ignored.
! 317: **
! 318: ** ^If an error occurs while evaluating the SQL statements passed into
! 319: ** sqlite3_exec(), then execution of the current statement stops and
! 320: ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()
! 321: ** is not NULL then any error message is written into memory obtained
! 322: ** from [sqlite3_malloc()] and passed back through the 5th parameter.
! 323: ** To avoid memory leaks, the application should invoke [sqlite3_free()]
! 324: ** on error message strings returned through the 5th parameter of
! 325: ** of sqlite3_exec() after the error message string is no longer needed.
! 326: ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
! 327: ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
! 328: ** NULL before returning.
! 329: **
! 330: ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()
! 331: ** routine returns SQLITE_ABORT without invoking the callback again and
! 332: ** without running any subsequent SQL statements.
! 333: **
! 334: ** ^The 2nd argument to the sqlite3_exec() callback function is the
! 335: ** number of columns in the result. ^The 3rd argument to the sqlite3_exec()
! 336: ** callback is an array of pointers to strings obtained as if from
! 337: ** [sqlite3_column_text()], one for each column. ^If an element of a
! 338: ** result row is NULL then the corresponding string pointer for the
! 339: ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the
! 340: ** sqlite3_exec() callback is an array of pointers to strings where each
! 341: ** entry represents the name of corresponding result column as obtained
! 342: ** from [sqlite3_column_name()].
! 343: **
! 344: ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer
! 345: ** to an empty string, or a pointer that contains only whitespace and/or
! 346: ** SQL comments, then no SQL statements are evaluated and the database
! 347: ** is not changed.
! 348: **
! 349: ** Restrictions:
! 350: **
! 351: ** <ul>
! 352: ** <li> The application must insure that the 1st parameter to sqlite3_exec()
! 353: ** is a valid and open [database connection].
! 354: ** <li> The application must not close [database connection] specified by
! 355: ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.
! 356: ** <li> The application must not modify the SQL statement text passed into
! 357: ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.
! 358: ** </ul>
! 359: */
! 360: SQLITE_API int sqlite3_exec(
! 361: sqlite3*, /* An open database */
! 362: const char *sql, /* SQL to be evaluated */
! 363: int (*callback)(void*,int,char**,char**), /* Callback function */
! 364: void *, /* 1st argument to callback */
! 365: char **errmsg /* Error msg written here */
! 366: );
! 367:
! 368: /*
! 369: ** CAPI3REF: Result Codes
! 370: ** KEYWORDS: SQLITE_OK {error code} {error codes}
! 371: ** KEYWORDS: {result code} {result codes}
! 372: **
! 373: ** Many SQLite functions return an integer result code from the set shown
! 374: ** here in order to indicate success or failure.
! 375: **
! 376: ** New error codes may be added in future versions of SQLite.
! 377: **
! 378: ** See also: [SQLITE_IOERR_READ | extended result codes],
! 379: ** [sqlite3_vtab_on_conflict()] [SQLITE_ROLLBACK | result codes].
! 380: */
! 381: #define SQLITE_OK 0 /* Successful result */
! 382: /* beginning-of-error-codes */
! 383: #define SQLITE_ERROR 1 /* SQL error or missing database */
! 384: #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */
! 385: #define SQLITE_PERM 3 /* Access permission denied */
! 386: #define SQLITE_ABORT 4 /* Callback routine requested an abort */
! 387: #define SQLITE_BUSY 5 /* The database file is locked */
! 388: #define SQLITE_LOCKED 6 /* A table in the database is locked */
! 389: #define SQLITE_NOMEM 7 /* A malloc() failed */
! 390: #define SQLITE_READONLY 8 /* Attempt to write a readonly database */
! 391: #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/
! 392: #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */
! 393: #define SQLITE_CORRUPT 11 /* The database disk image is malformed */
! 394: #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */
! 395: #define SQLITE_FULL 13 /* Insertion failed because database is full */
! 396: #define SQLITE_CANTOPEN 14 /* Unable to open the database file */
! 397: #define SQLITE_PROTOCOL 15 /* Database lock protocol error */
! 398: #define SQLITE_EMPTY 16 /* Database is empty */
! 399: #define SQLITE_SCHEMA 17 /* The database schema changed */
! 400: #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */
! 401: #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */
! 402: #define SQLITE_MISMATCH 20 /* Data type mismatch */
! 403: #define SQLITE_MISUSE 21 /* Library used incorrectly */
! 404: #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */
! 405: #define SQLITE_AUTH 23 /* Authorization denied */
! 406: #define SQLITE_FORMAT 24 /* Auxiliary database format error */
! 407: #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */
! 408: #define SQLITE_NOTADB 26 /* File opened that is not a database file */
! 409: #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */
! 410: #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */
! 411: /* end-of-error-codes */
! 412:
! 413: /*
! 414: ** CAPI3REF: Extended Result Codes
! 415: ** KEYWORDS: {extended error code} {extended error codes}
! 416: ** KEYWORDS: {extended result code} {extended result codes}
! 417: **
! 418: ** In its default configuration, SQLite API routines return one of 26 integer
! 419: ** [SQLITE_OK | result codes]. However, experience has shown that many of
! 420: ** these result codes are too coarse-grained. They do not provide as
! 421: ** much information about problems as programmers might like. In an effort to
! 422: ** address this, newer versions of SQLite (version 3.3.8 and later) include
! 423: ** support for additional result codes that provide more detailed information
! 424: ** about errors. The extended result codes are enabled or disabled
! 425: ** on a per database connection basis using the
! 426: ** [sqlite3_extended_result_codes()] API.
! 427: **
! 428: ** Some of the available extended result codes are listed here.
! 429: ** One may expect the number of extended result codes will be expand
! 430: ** over time. Software that uses extended result codes should expect
! 431: ** to see new result codes in future releases of SQLite.
! 432: **
! 433: ** The SQLITE_OK result code will never be extended. It will always
! 434: ** be exactly zero.
! 435: */
! 436: #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))
! 437: #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))
! 438: #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))
! 439: #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))
! 440: #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))
! 441: #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))
! 442: #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))
! 443: #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))
! 444: #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))
! 445: #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))
! 446: #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))
! 447: #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))
! 448: #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))
! 449: #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))
! 450: #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))
! 451: #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))
! 452: #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))
! 453: #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))
! 454: #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))
! 455: #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))
! 456: #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))
! 457: #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))
! 458: #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))
! 459: #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))
! 460: #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))
! 461: #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))
! 462: #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))
! 463: #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))
! 464:
! 465: /*
! 466: ** CAPI3REF: Flags For File Open Operations
! 467: **
! 468: ** These bit values are intended for use in the
! 469: ** 3rd parameter to the [sqlite3_open_v2()] interface and
! 470: ** in the 4th parameter to the [sqlite3_vfs.xOpen] method.
! 471: */
! 472: #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */
! 473: #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */
! 474: #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */
! 475: #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */
! 476: #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */
! 477: #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */
! 478: #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */
! 479: #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */
! 480: #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */
! 481: #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */
! 482: #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */
! 483: #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */
! 484: #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */
! 485: #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */
! 486: #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */
! 487: #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */
! 488: #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */
! 489: #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */
! 490: #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */
! 491:
! 492: /* Reserved: 0x00F00000 */
! 493:
! 494: /*
! 495: ** CAPI3REF: Device Characteristics
! 496: **
! 497: ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
! 498: ** object returns an integer which is a vector of the these
! 499: ** bit values expressing I/O characteristics of the mass storage
! 500: ** device that holds the file that the [sqlite3_io_methods]
! 501: ** refers to.
! 502: **
! 503: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
! 504: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
! 505: ** mean that writes of blocks that are nnn bytes in size and
! 506: ** are aligned to an address which is an integer multiple of
! 507: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
! 508: ** that when data is appended to a file, the data is appended
! 509: ** first then the size of the file is extended, never the other
! 510: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
! 511: ** information is written to disk in the same order as calls
! 512: ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that
! 513: ** after reboot following a crash or power loss, the only bytes in a
! 514: ** file that were written at the application level might have changed
! 515: ** and that adjacent bytes, even bytes within the same sector are
! 516: ** guaranteed to be unchanged.
! 517: */
! 518: #define SQLITE_IOCAP_ATOMIC 0x00000001
! 519: #define SQLITE_IOCAP_ATOMIC512 0x00000002
! 520: #define SQLITE_IOCAP_ATOMIC1K 0x00000004
! 521: #define SQLITE_IOCAP_ATOMIC2K 0x00000008
! 522: #define SQLITE_IOCAP_ATOMIC4K 0x00000010
! 523: #define SQLITE_IOCAP_ATOMIC8K 0x00000020
! 524: #define SQLITE_IOCAP_ATOMIC16K 0x00000040
! 525: #define SQLITE_IOCAP_ATOMIC32K 0x00000080
! 526: #define SQLITE_IOCAP_ATOMIC64K 0x00000100
! 527: #define SQLITE_IOCAP_SAFE_APPEND 0x00000200
! 528: #define SQLITE_IOCAP_SEQUENTIAL 0x00000400
! 529: #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800
! 530: #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000
! 531:
! 532: /*
! 533: ** CAPI3REF: File Locking Levels
! 534: **
! 535: ** SQLite uses one of these integer values as the second
! 536: ** argument to calls it makes to the xLock() and xUnlock() methods
! 537: ** of an [sqlite3_io_methods] object.
! 538: */
! 539: #define SQLITE_LOCK_NONE 0
! 540: #define SQLITE_LOCK_SHARED 1
! 541: #define SQLITE_LOCK_RESERVED 2
! 542: #define SQLITE_LOCK_PENDING 3
! 543: #define SQLITE_LOCK_EXCLUSIVE 4
! 544:
! 545: /*
! 546: ** CAPI3REF: Synchronization Type Flags
! 547: **
! 548: ** When SQLite invokes the xSync() method of an
! 549: ** [sqlite3_io_methods] object it uses a combination of
! 550: ** these integer values as the second argument.
! 551: **
! 552: ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the
! 553: ** sync operation only needs to flush data to mass storage. Inode
! 554: ** information need not be flushed. If the lower four bits of the flag
! 555: ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.
! 556: ** If the lower four bits equal SQLITE_SYNC_FULL, that means
! 557: ** to use Mac OS X style fullsync instead of fsync().
! 558: **
! 559: ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags
! 560: ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL
! 561: ** settings. The [synchronous pragma] determines when calls to the
! 562: ** xSync VFS method occur and applies uniformly across all platforms.
! 563: ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how
! 564: ** energetic or rigorous or forceful the sync operations are and
! 565: ** only make a difference on Mac OSX for the default SQLite code.
! 566: ** (Third-party VFS implementations might also make the distinction
! 567: ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the
! 568: ** operating systems natively supported by SQLite, only Mac OSX
! 569: ** cares about the difference.)
! 570: */
! 571: #define SQLITE_SYNC_NORMAL 0x00002
! 572: #define SQLITE_SYNC_FULL 0x00003
! 573: #define SQLITE_SYNC_DATAONLY 0x00010
! 574:
! 575: /*
! 576: ** CAPI3REF: OS Interface Open File Handle
! 577: **
! 578: ** An [sqlite3_file] object represents an open file in the
! 579: ** [sqlite3_vfs | OS interface layer]. Individual OS interface
! 580: ** implementations will
! 581: ** want to subclass this object by appending additional fields
! 582: ** for their own use. The pMethods entry is a pointer to an
! 583: ** [sqlite3_io_methods] object that defines methods for performing
! 584: ** I/O operations on the open file.
! 585: */
! 586: typedef struct sqlite3_file sqlite3_file;
! 587: struct sqlite3_file {
! 588: const struct sqlite3_io_methods *pMethods; /* Methods for an open file */
! 589: };
! 590:
! 591: /*
! 592: ** CAPI3REF: OS Interface File Virtual Methods Object
! 593: **
! 594: ** Every file opened by the [sqlite3_vfs.xOpen] method populates an
! 595: ** [sqlite3_file] object (or, more commonly, a subclass of the
! 596: ** [sqlite3_file] object) with a pointer to an instance of this object.
! 597: ** This object defines the methods used to perform various operations
! 598: ** against the open file represented by the [sqlite3_file] object.
! 599: **
! 600: ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element
! 601: ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method
! 602: ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The
! 603: ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]
! 604: ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element
! 605: ** to NULL.
! 606: **
! 607: ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or
! 608: ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().
! 609: ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]
! 610: ** flag may be ORed in to indicate that only the data of the file
! 611: ** and not its inode needs to be synced.
! 612: **
! 613: ** The integer values to xLock() and xUnlock() are one of
! 614: ** <ul>
! 615: ** <li> [SQLITE_LOCK_NONE],
! 616: ** <li> [SQLITE_LOCK_SHARED],
! 617: ** <li> [SQLITE_LOCK_RESERVED],
! 618: ** <li> [SQLITE_LOCK_PENDING], or
! 619: ** <li> [SQLITE_LOCK_EXCLUSIVE].
! 620: ** </ul>
! 621: ** xLock() increases the lock. xUnlock() decreases the lock.
! 622: ** The xCheckReservedLock() method checks whether any database connection,
! 623: ** either in this process or in some other process, is holding a RESERVED,
! 624: ** PENDING, or EXCLUSIVE lock on the file. It returns true
! 625: ** if such a lock exists and false otherwise.
! 626: **
! 627: ** The xFileControl() method is a generic interface that allows custom
! 628: ** VFS implementations to directly control an open file using the
! 629: ** [sqlite3_file_control()] interface. The second "op" argument is an
! 630: ** integer opcode. The third argument is a generic pointer intended to
! 631: ** point to a structure that may contain arguments or space in which to
! 632: ** write return values. Potential uses for xFileControl() might be
! 633: ** functions to enable blocking locks with timeouts, to change the
! 634: ** locking strategy (for example to use dot-file locks), to inquire
! 635: ** about the status of a lock, or to break stale locks. The SQLite
! 636: ** core reserves all opcodes less than 100 for its own use.
! 637: ** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available.
! 638: ** Applications that define a custom xFileControl method should use opcodes
! 639: ** greater than 100 to avoid conflicts. VFS implementations should
! 640: ** return [SQLITE_NOTFOUND] for file control opcodes that they do not
! 641: ** recognize.
! 642: **
! 643: ** The xSectorSize() method returns the sector size of the
! 644: ** device that underlies the file. The sector size is the
! 645: ** minimum write that can be performed without disturbing
! 646: ** other bytes in the file. The xDeviceCharacteristics()
! 647: ** method returns a bit vector describing behaviors of the
! 648: ** underlying device:
! 649: **
! 650: ** <ul>
! 651: ** <li> [SQLITE_IOCAP_ATOMIC]
! 652: ** <li> [SQLITE_IOCAP_ATOMIC512]
! 653: ** <li> [SQLITE_IOCAP_ATOMIC1K]
! 654: ** <li> [SQLITE_IOCAP_ATOMIC2K]
! 655: ** <li> [SQLITE_IOCAP_ATOMIC4K]
! 656: ** <li> [SQLITE_IOCAP_ATOMIC8K]
! 657: ** <li> [SQLITE_IOCAP_ATOMIC16K]
! 658: ** <li> [SQLITE_IOCAP_ATOMIC32K]
! 659: ** <li> [SQLITE_IOCAP_ATOMIC64K]
! 660: ** <li> [SQLITE_IOCAP_SAFE_APPEND]
! 661: ** <li> [SQLITE_IOCAP_SEQUENTIAL]
! 662: ** </ul>
! 663: **
! 664: ** The SQLITE_IOCAP_ATOMIC property means that all writes of
! 665: ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values
! 666: ** mean that writes of blocks that are nnn bytes in size and
! 667: ** are aligned to an address which is an integer multiple of
! 668: ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means
! 669: ** that when data is appended to a file, the data is appended
! 670: ** first then the size of the file is extended, never the other
! 671: ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that
! 672: ** information is written to disk in the same order as calls
! 673: ** to xWrite().
! 674: **
! 675: ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill
! 676: ** in the unread portions of the buffer with zeros. A VFS that
! 677: ** fails to zero-fill short reads might seem to work. However,
! 678: ** failure to zero-fill short reads will eventually lead to
! 679: ** database corruption.
! 680: */
! 681: typedef struct sqlite3_io_methods sqlite3_io_methods;
! 682: struct sqlite3_io_methods {
! 683: int iVersion;
! 684: int (*xClose)(sqlite3_file*);
! 685: int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
! 686: int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst);
! 687: int (*xTruncate)(sqlite3_file*, sqlite3_int64 size);
! 688: int (*xSync)(sqlite3_file*, int flags);
! 689: int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize);
! 690: int (*xLock)(sqlite3_file*, int);
! 691: int (*xUnlock)(sqlite3_file*, int);
! 692: int (*xCheckReservedLock)(sqlite3_file*, int *pResOut);
! 693: int (*xFileControl)(sqlite3_file*, int op, void *pArg);
! 694: int (*xSectorSize)(sqlite3_file*);
! 695: int (*xDeviceCharacteristics)(sqlite3_file*);
! 696: /* Methods above are valid for version 1 */
! 697: int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**);
! 698: int (*xShmLock)(sqlite3_file*, int offset, int n, int flags);
! 699: void (*xShmBarrier)(sqlite3_file*);
! 700: int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
! 701: /* Methods above are valid for version 2 */
! 702: /* Additional methods may be added in future releases */
! 703: };
! 704:
! 705: /*
! 706: ** CAPI3REF: Standard File Control Opcodes
! 707: **
! 708: ** These integer constants are opcodes for the xFileControl method
! 709: ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]
! 710: ** interface.
! 711: **
! 712: ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This
! 713: ** opcode causes the xFileControl method to write the current state of
! 714: ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
! 715: ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
! 716: ** into an integer that the pArg argument points to. This capability
! 717: ** is used during testing and only needs to be supported when SQLITE_TEST
! 718: ** is defined.
! 719: **
! 720: ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
! 721: ** layer a hint of how large the database file will grow to be during the
! 722: ** current transaction. This hint is not guaranteed to be accurate but it
! 723: ** is often close. The underlying VFS might choose to preallocate database
! 724: ** file space based on this hint in order to help writes to the database
! 725: ** file run faster.
! 726: **
! 727: ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS
! 728: ** extends and truncates the database file in chunks of a size specified
! 729: ** by the user. The fourth argument to [sqlite3_file_control()] should
! 730: ** point to an integer (type int) containing the new chunk-size to use
! 731: ** for the nominated database. Allocating database file space in large
! 732: ** chunks (say 1MB at a time), may reduce file-system fragmentation and
! 733: ** improve performance on some systems.
! 734: **
! 735: ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer
! 736: ** to the [sqlite3_file] object associated with a particular database
! 737: ** connection. See the [sqlite3_file_control()] documentation for
! 738: ** additional information.
! 739: **
! 740: ** ^(The [SQLITE_FCNTL_SYNC_OMITTED] opcode is generated internally by
! 741: ** SQLite and sent to all VFSes in place of a call to the xSync method
! 742: ** when the database connection has [PRAGMA synchronous] set to OFF.)^
! 743: ** Some specialized VFSes need this signal in order to operate correctly
! 744: ** when [PRAGMA synchronous | PRAGMA synchronous=OFF] is set, but most
! 745: ** VFSes do not need this signal and should silently ignore this opcode.
! 746: ** Applications should not call [sqlite3_file_control()] with this
! 747: ** opcode as doing so may disrupt the operation of the specialized VFSes
! 748: ** that do require it.
! 749: **
! 750: ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic
! 751: ** retry counts and intervals for certain disk I/O operations for the
! 752: ** windows [VFS] in order to provide robustness in the presence of
! 753: ** anti-virus programs. By default, the windows VFS will retry file read,
! 754: ** file write, and file delete operations up to 10 times, with a delay
! 755: ** of 25 milliseconds before the first retry and with the delay increasing
! 756: ** by an additional 25 milliseconds with each subsequent retry. This
! 757: ** opcode allows these two values (10 retries and 25 milliseconds of delay)
! 758: ** to be adjusted. The values are changed for all database connections
! 759: ** within the same process. The argument is a pointer to an array of two
! 760: ** integers where the first integer i the new retry count and the second
! 761: ** integer is the delay. If either integer is negative, then the setting
! 762: ** is not changed but instead the prior value of that setting is written
! 763: ** into the array entry, allowing the current retry settings to be
! 764: ** interrogated. The zDbName parameter is ignored.
! 765: **
! 766: ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the
! 767: ** persistent [WAL | Write AHead Log] setting. By default, the auxiliary
! 768: ** write ahead log and shared memory files used for transaction control
! 769: ** are automatically deleted when the latest connection to the database
! 770: ** closes. Setting persistent WAL mode causes those files to persist after
! 771: ** close. Persisting the files is useful when other processes that do not
! 772: ** have write permission on the directory containing the database file want
! 773: ** to read the database file, as the WAL and shared memory files must exist
! 774: ** in order for the database to be readable. The fourth parameter to
! 775: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
! 776: ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent
! 777: ** WAL mode. If the integer is -1, then it is overwritten with the current
! 778: ** WAL persistence setting.
! 779: **
! 780: ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the
! 781: ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting
! 782: ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the
! 783: ** xDeviceCharacteristics methods. The fourth parameter to
! 784: ** [sqlite3_file_control()] for this opcode should be a pointer to an integer.
! 785: ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage
! 786: ** mode. If the integer is -1, then it is overwritten with the current
! 787: ** zero-damage mode setting.
! 788: **
! 789: ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening
! 790: ** a write transaction to indicate that, unless it is rolled back for some
! 791: ** reason, the entire database file will be overwritten by the current
! 792: ** transaction. This is used by VACUUM operations.
! 793: **
! 794: ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of
! 795: ** all [VFSes] in the VFS stack. The names are of all VFS shims and the
! 796: ** final bottom-level VFS are written into memory obtained from
! 797: ** [sqlite3_malloc()] and the result is stored in the char* variable
! 798: ** that the fourth parameter of [sqlite3_file_control()] points to.
! 799: ** The caller is responsible for freeing the memory when done. As with
! 800: ** all file-control actions, there is no guarantee that this will actually
! 801: ** do anything. Callers should initialize the char* variable to a NULL
! 802: ** pointer in case this file-control is not implemented. This file-control
! 803: ** is intended for diagnostic use only.
! 804: */
! 805: #define SQLITE_FCNTL_LOCKSTATE 1
! 806: #define SQLITE_GET_LOCKPROXYFILE 2
! 807: #define SQLITE_SET_LOCKPROXYFILE 3
! 808: #define SQLITE_LAST_ERRNO 4
! 809: #define SQLITE_FCNTL_SIZE_HINT 5
! 810: #define SQLITE_FCNTL_CHUNK_SIZE 6
! 811: #define SQLITE_FCNTL_FILE_POINTER 7
! 812: #define SQLITE_FCNTL_SYNC_OMITTED 8
! 813: #define SQLITE_FCNTL_WIN32_AV_RETRY 9
! 814: #define SQLITE_FCNTL_PERSIST_WAL 10
! 815: #define SQLITE_FCNTL_OVERWRITE 11
! 816: #define SQLITE_FCNTL_VFSNAME 12
! 817: #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13
! 818:
! 819: /*
! 820: ** CAPI3REF: Mutex Handle
! 821: **
! 822: ** The mutex module within SQLite defines [sqlite3_mutex] to be an
! 823: ** abstract type for a mutex object. The SQLite core never looks
! 824: ** at the internal representation of an [sqlite3_mutex]. It only
! 825: ** deals with pointers to the [sqlite3_mutex] object.
! 826: **
! 827: ** Mutexes are created using [sqlite3_mutex_alloc()].
! 828: */
! 829: typedef struct sqlite3_mutex sqlite3_mutex;
! 830:
! 831: /*
! 832: ** CAPI3REF: OS Interface Object
! 833: **
! 834: ** An instance of the sqlite3_vfs object defines the interface between
! 835: ** the SQLite core and the underlying operating system. The "vfs"
! 836: ** in the name of the object stands for "virtual file system". See
! 837: ** the [VFS | VFS documentation] for further information.
! 838: **
! 839: ** The value of the iVersion field is initially 1 but may be larger in
! 840: ** future versions of SQLite. Additional fields may be appended to this
! 841: ** object when the iVersion value is increased. Note that the structure
! 842: ** of the sqlite3_vfs object changes in the transaction between
! 843: ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not
! 844: ** modified.
! 845: **
! 846: ** The szOsFile field is the size of the subclassed [sqlite3_file]
! 847: ** structure used by this VFS. mxPathname is the maximum length of
! 848: ** a pathname in this VFS.
! 849: **
! 850: ** Registered sqlite3_vfs objects are kept on a linked list formed by
! 851: ** the pNext pointer. The [sqlite3_vfs_register()]
! 852: ** and [sqlite3_vfs_unregister()] interfaces manage this list
! 853: ** in a thread-safe way. The [sqlite3_vfs_find()] interface
! 854: ** searches the list. Neither the application code nor the VFS
! 855: ** implementation should use the pNext pointer.
! 856: **
! 857: ** The pNext field is the only field in the sqlite3_vfs
! 858: ** structure that SQLite will ever modify. SQLite will only access
! 859: ** or modify this field while holding a particular static mutex.
! 860: ** The application should never modify anything within the sqlite3_vfs
! 861: ** object once the object has been registered.
! 862: **
! 863: ** The zName field holds the name of the VFS module. The name must
! 864: ** be unique across all VFS modules.
! 865: **
! 866: ** [[sqlite3_vfs.xOpen]]
! 867: ** ^SQLite guarantees that the zFilename parameter to xOpen
! 868: ** is either a NULL pointer or string obtained
! 869: ** from xFullPathname() with an optional suffix added.
! 870: ** ^If a suffix is added to the zFilename parameter, it will
! 871: ** consist of a single "-" character followed by no more than
! 872: ** 11 alphanumeric and/or "-" characters.
! 873: ** ^SQLite further guarantees that
! 874: ** the string will be valid and unchanged until xClose() is
! 875: ** called. Because of the previous sentence,
! 876: ** the [sqlite3_file] can safely store a pointer to the
! 877: ** filename if it needs to remember the filename for some reason.
! 878: ** If the zFilename parameter to xOpen is a NULL pointer then xOpen
! 879: ** must invent its own temporary name for the file. ^Whenever the
! 880: ** xFilename parameter is NULL it will also be the case that the
! 881: ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].
! 882: **
! 883: ** The flags argument to xOpen() includes all bits set in
! 884: ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]
! 885: ** or [sqlite3_open16()] is used, then flags includes at least
! 886: ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE].
! 887: ** If xOpen() opens a file read-only then it sets *pOutFlags to
! 888: ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.
! 889: **
! 890: ** ^(SQLite will also add one of the following flags to the xOpen()
! 891: ** call, depending on the object being opened:
! 892: **
! 893: ** <ul>
! 894: ** <li> [SQLITE_OPEN_MAIN_DB]
! 895: ** <li> [SQLITE_OPEN_MAIN_JOURNAL]
! 896: ** <li> [SQLITE_OPEN_TEMP_DB]
! 897: ** <li> [SQLITE_OPEN_TEMP_JOURNAL]
! 898: ** <li> [SQLITE_OPEN_TRANSIENT_DB]
! 899: ** <li> [SQLITE_OPEN_SUBJOURNAL]
! 900: ** <li> [SQLITE_OPEN_MASTER_JOURNAL]
! 901: ** <li> [SQLITE_OPEN_WAL]
! 902: ** </ul>)^
! 903: **
! 904: ** The file I/O implementation can use the object type flags to
! 905: ** change the way it deals with files. For example, an application
! 906: ** that does not care about crash recovery or rollback might make
! 907: ** the open of a journal file a no-op. Writes to this journal would
! 908: ** also be no-ops, and any attempt to read the journal would return
! 909: ** SQLITE_IOERR. Or the implementation might recognize that a database
! 910: ** file will be doing page-aligned sector reads and writes in a random
! 911: ** order and set up its I/O subsystem accordingly.
! 912: **
! 913: ** SQLite might also add one of the following flags to the xOpen method:
! 914: **
! 915: ** <ul>
! 916: ** <li> [SQLITE_OPEN_DELETEONCLOSE]
! 917: ** <li> [SQLITE_OPEN_EXCLUSIVE]
! 918: ** </ul>
! 919: **
! 920: ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be
! 921: ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]
! 922: ** will be set for TEMP databases and their journals, transient
! 923: ** databases, and subjournals.
! 924: **
! 925: ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction
! 926: ** with the [SQLITE_OPEN_CREATE] flag, which are both directly
! 927: ** analogous to the O_EXCL and O_CREAT flags of the POSIX open()
! 928: ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the
! 929: ** SQLITE_OPEN_CREATE, is used to indicate that file should always
! 930: ** be created, and that it is an error if it already exists.
! 931: ** It is <i>not</i> used to indicate the file should be opened
! 932: ** for exclusive access.
! 933: **
! 934: ** ^At least szOsFile bytes of memory are allocated by SQLite
! 935: ** to hold the [sqlite3_file] structure passed as the third
! 936: ** argument to xOpen. The xOpen method does not have to
! 937: ** allocate the structure; it should just fill it in. Note that
! 938: ** the xOpen method must set the sqlite3_file.pMethods to either
! 939: ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do
! 940: ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods
! 941: ** element will be valid after xOpen returns regardless of the success
! 942: ** or failure of the xOpen call.
! 943: **
! 944: ** [[sqlite3_vfs.xAccess]]
! 945: ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]
! 946: ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to
! 947: ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]
! 948: ** to test whether a file is at least readable. The file can be a
! 949: ** directory.
! 950: **
! 951: ** ^SQLite will always allocate at least mxPathname+1 bytes for the
! 952: ** output buffer xFullPathname. The exact size of the output buffer
! 953: ** is also passed as a parameter to both methods. If the output buffer
! 954: ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is
! 955: ** handled as a fatal error by SQLite, vfs implementations should endeavor
! 956: ** to prevent this by setting mxPathname to a sufficiently large value.
! 957: **
! 958: ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()
! 959: ** interfaces are not strictly a part of the filesystem, but they are
! 960: ** included in the VFS structure for completeness.
! 961: ** The xRandomness() function attempts to return nBytes bytes
! 962: ** of good-quality randomness into zOut. The return value is
! 963: ** the actual number of bytes of randomness obtained.
! 964: ** The xSleep() method causes the calling thread to sleep for at
! 965: ** least the number of microseconds given. ^The xCurrentTime()
! 966: ** method returns a Julian Day Number for the current date and time as
! 967: ** a floating point value.
! 968: ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian
! 969: ** Day Number multiplied by 86400000 (the number of milliseconds in
! 970: ** a 24-hour day).
! 971: ** ^SQLite will use the xCurrentTimeInt64() method to get the current
! 972: ** date and time if that method is available (if iVersion is 2 or
! 973: ** greater and the function pointer is not NULL) and will fall back
! 974: ** to xCurrentTime() if xCurrentTimeInt64() is unavailable.
! 975: **
! 976: ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces
! 977: ** are not used by the SQLite core. These optional interfaces are provided
! 978: ** by some VFSes to facilitate testing of the VFS code. By overriding
! 979: ** system calls with functions under its control, a test program can
! 980: ** simulate faults and error conditions that would otherwise be difficult
! 981: ** or impossible to induce. The set of system calls that can be overridden
! 982: ** varies from one VFS to another, and from one version of the same VFS to the
! 983: ** next. Applications that use these interfaces must be prepared for any
! 984: ** or all of these interfaces to be NULL or for their behavior to change
! 985: ** from one release to the next. Applications must not attempt to access
! 986: ** any of these methods if the iVersion of the VFS is less than 3.
! 987: */
! 988: typedef struct sqlite3_vfs sqlite3_vfs;
! 989: typedef void (*sqlite3_syscall_ptr)(void);
! 990: struct sqlite3_vfs {
! 991: int iVersion; /* Structure version number (currently 3) */
! 992: int szOsFile; /* Size of subclassed sqlite3_file */
! 993: int mxPathname; /* Maximum file pathname length */
! 994: sqlite3_vfs *pNext; /* Next registered VFS */
! 995: const char *zName; /* Name of this virtual file system */
! 996: void *pAppData; /* Pointer to application-specific data */
! 997: int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
! 998: int flags, int *pOutFlags);
! 999: int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
! 1000: int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
! 1001: int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
! 1002: void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
! 1003: void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
! 1004: void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);
! 1005: void (*xDlClose)(sqlite3_vfs*, void*);
! 1006: int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
! 1007: int (*xSleep)(sqlite3_vfs*, int microseconds);
! 1008: int (*xCurrentTime)(sqlite3_vfs*, double*);
! 1009: int (*xGetLastError)(sqlite3_vfs*, int, char *);
! 1010: /*
! 1011: ** The methods above are in version 1 of the sqlite_vfs object
! 1012: ** definition. Those that follow are added in version 2 or later
! 1013: */
! 1014: int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*);
! 1015: /*
! 1016: ** The methods above are in versions 1 and 2 of the sqlite_vfs object.
! 1017: ** Those below are for version 3 and greater.
! 1018: */
! 1019: int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr);
! 1020: sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName);
! 1021: const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName);
! 1022: /*
! 1023: ** The methods above are in versions 1 through 3 of the sqlite_vfs object.
! 1024: ** New fields may be appended in figure versions. The iVersion
! 1025: ** value will increment whenever this happens.
! 1026: */
! 1027: };
! 1028:
! 1029: /*
! 1030: ** CAPI3REF: Flags for the xAccess VFS method
! 1031: **
! 1032: ** These integer constants can be used as the third parameter to
! 1033: ** the xAccess method of an [sqlite3_vfs] object. They determine
! 1034: ** what kind of permissions the xAccess method is looking for.
! 1035: ** With SQLITE_ACCESS_EXISTS, the xAccess method
! 1036: ** simply checks whether the file exists.
! 1037: ** With SQLITE_ACCESS_READWRITE, the xAccess method
! 1038: ** checks whether the named directory is both readable and writable
! 1039: ** (in other words, if files can be added, removed, and renamed within
! 1040: ** the directory).
! 1041: ** The SQLITE_ACCESS_READWRITE constant is currently used only by the
! 1042: ** [temp_store_directory pragma], though this could change in a future
! 1043: ** release of SQLite.
! 1044: ** With SQLITE_ACCESS_READ, the xAccess method
! 1045: ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is
! 1046: ** currently unused, though it might be used in a future release of
! 1047: ** SQLite.
! 1048: */
! 1049: #define SQLITE_ACCESS_EXISTS 0
! 1050: #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */
! 1051: #define SQLITE_ACCESS_READ 2 /* Unused */
! 1052:
! 1053: /*
! 1054: ** CAPI3REF: Flags for the xShmLock VFS method
! 1055: **
! 1056: ** These integer constants define the various locking operations
! 1057: ** allowed by the xShmLock method of [sqlite3_io_methods]. The
! 1058: ** following are the only legal combinations of flags to the
! 1059: ** xShmLock method:
! 1060: **
! 1061: ** <ul>
! 1062: ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED
! 1063: ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE
! 1064: ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED
! 1065: ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE
! 1066: ** </ul>
! 1067: **
! 1068: ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as
! 1069: ** was given no the corresponding lock.
! 1070: **
! 1071: ** The xShmLock method can transition between unlocked and SHARED or
! 1072: ** between unlocked and EXCLUSIVE. It cannot transition between SHARED
! 1073: ** and EXCLUSIVE.
! 1074: */
! 1075: #define SQLITE_SHM_UNLOCK 1
! 1076: #define SQLITE_SHM_LOCK 2
! 1077: #define SQLITE_SHM_SHARED 4
! 1078: #define SQLITE_SHM_EXCLUSIVE 8
! 1079:
! 1080: /*
! 1081: ** CAPI3REF: Maximum xShmLock index
! 1082: **
! 1083: ** The xShmLock method on [sqlite3_io_methods] may use values
! 1084: ** between 0 and this upper bound as its "offset" argument.
! 1085: ** The SQLite core will never attempt to acquire or release a
! 1086: ** lock outside of this range
! 1087: */
! 1088: #define SQLITE_SHM_NLOCK 8
! 1089:
! 1090:
! 1091: /*
! 1092: ** CAPI3REF: Initialize The SQLite Library
! 1093: **
! 1094: ** ^The sqlite3_initialize() routine initializes the
! 1095: ** SQLite library. ^The sqlite3_shutdown() routine
! 1096: ** deallocates any resources that were allocated by sqlite3_initialize().
! 1097: ** These routines are designed to aid in process initialization and
! 1098: ** shutdown on embedded systems. Workstation applications using
! 1099: ** SQLite normally do not need to invoke either of these routines.
! 1100: **
! 1101: ** A call to sqlite3_initialize() is an "effective" call if it is
! 1102: ** the first time sqlite3_initialize() is invoked during the lifetime of
! 1103: ** the process, or if it is the first time sqlite3_initialize() is invoked
! 1104: ** following a call to sqlite3_shutdown(). ^(Only an effective call
! 1105: ** of sqlite3_initialize() does any initialization. All other calls
! 1106: ** are harmless no-ops.)^
! 1107: **
! 1108: ** A call to sqlite3_shutdown() is an "effective" call if it is the first
! 1109: ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only
! 1110: ** an effective call to sqlite3_shutdown() does any deinitialization.
! 1111: ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^
! 1112: **
! 1113: ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()
! 1114: ** is not. The sqlite3_shutdown() interface must only be called from a
! 1115: ** single thread. All open [database connections] must be closed and all
! 1116: ** other SQLite resources must be deallocated prior to invoking
! 1117: ** sqlite3_shutdown().
! 1118: **
! 1119: ** Among other things, ^sqlite3_initialize() will invoke
! 1120: ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()
! 1121: ** will invoke sqlite3_os_end().
! 1122: **
! 1123: ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.
! 1124: ** ^If for some reason, sqlite3_initialize() is unable to initialize
! 1125: ** the library (perhaps it is unable to allocate a needed resource such
! 1126: ** as a mutex) it returns an [error code] other than [SQLITE_OK].
! 1127: **
! 1128: ** ^The sqlite3_initialize() routine is called internally by many other
! 1129: ** SQLite interfaces so that an application usually does not need to
! 1130: ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]
! 1131: ** calls sqlite3_initialize() so the SQLite library will be automatically
! 1132: ** initialized when [sqlite3_open()] is called if it has not be initialized
! 1133: ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
! 1134: ** compile-time option, then the automatic calls to sqlite3_initialize()
! 1135: ** are omitted and the application must call sqlite3_initialize() directly
! 1136: ** prior to using any other SQLite interface. For maximum portability,
! 1137: ** it is recommended that applications always invoke sqlite3_initialize()
! 1138: ** directly prior to using any other SQLite interface. Future releases
! 1139: ** of SQLite may require this. In other words, the behavior exhibited
! 1140: ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
! 1141: ** default behavior in some future release of SQLite.
! 1142: **
! 1143: ** The sqlite3_os_init() routine does operating-system specific
! 1144: ** initialization of the SQLite library. The sqlite3_os_end()
! 1145: ** routine undoes the effect of sqlite3_os_init(). Typical tasks
! 1146: ** performed by these routines include allocation or deallocation
! 1147: ** of static resources, initialization of global variables,
! 1148: ** setting up a default [sqlite3_vfs] module, or setting up
! 1149: ** a default configuration using [sqlite3_config()].
! 1150: **
! 1151: ** The application should never invoke either sqlite3_os_init()
! 1152: ** or sqlite3_os_end() directly. The application should only invoke
! 1153: ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()
! 1154: ** interface is called automatically by sqlite3_initialize() and
! 1155: ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate
! 1156: ** implementations for sqlite3_os_init() and sqlite3_os_end()
! 1157: ** are built into SQLite when it is compiled for Unix, Windows, or OS/2.
! 1158: ** When [custom builds | built for other platforms]
! 1159: ** (using the [SQLITE_OS_OTHER=1] compile-time
! 1160: ** option) the application must supply a suitable implementation for
! 1161: ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied
! 1162: ** implementation of sqlite3_os_init() or sqlite3_os_end()
! 1163: ** must return [SQLITE_OK] on success and some other [error code] upon
! 1164: ** failure.
! 1165: */
! 1166: SQLITE_API int sqlite3_initialize(void);
! 1167: SQLITE_API int sqlite3_shutdown(void);
! 1168: SQLITE_API int sqlite3_os_init(void);
! 1169: SQLITE_API int sqlite3_os_end(void);
! 1170:
! 1171: /*
! 1172: ** CAPI3REF: Configuring The SQLite Library
! 1173: **
! 1174: ** The sqlite3_config() interface is used to make global configuration
! 1175: ** changes to SQLite in order to tune SQLite to the specific needs of
! 1176: ** the application. The default configuration is recommended for most
! 1177: ** applications and so this routine is usually not necessary. It is
! 1178: ** provided to support rare applications with unusual needs.
! 1179: **
! 1180: ** The sqlite3_config() interface is not threadsafe. The application
! 1181: ** must insure that no other SQLite interfaces are invoked by other
! 1182: ** threads while sqlite3_config() is running. Furthermore, sqlite3_config()
! 1183: ** may only be invoked prior to library initialization using
! 1184: ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
! 1185: ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
! 1186: ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
! 1187: ** Note, however, that ^sqlite3_config() can be called as part of the
! 1188: ** implementation of an application-defined [sqlite3_os_init()].
! 1189: **
! 1190: ** The first argument to sqlite3_config() is an integer
! 1191: ** [configuration option] that determines
! 1192: ** what property of SQLite is to be configured. Subsequent arguments
! 1193: ** vary depending on the [configuration option]
! 1194: ** in the first argument.
! 1195: **
! 1196: ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
! 1197: ** ^If the option is unknown or SQLite is unable to set the option
! 1198: ** then this routine returns a non-zero [error code].
! 1199: */
! 1200: SQLITE_API int sqlite3_config(int, ...);
! 1201:
! 1202: /*
! 1203: ** CAPI3REF: Configure database connections
! 1204: **
! 1205: ** The sqlite3_db_config() interface is used to make configuration
! 1206: ** changes to a [database connection]. The interface is similar to
! 1207: ** [sqlite3_config()] except that the changes apply to a single
! 1208: ** [database connection] (specified in the first argument).
! 1209: **
! 1210: ** The second argument to sqlite3_db_config(D,V,...) is the
! 1211: ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code
! 1212: ** that indicates what aspect of the [database connection] is being configured.
! 1213: ** Subsequent arguments vary depending on the configuration verb.
! 1214: **
! 1215: ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if
! 1216: ** the call is considered successful.
! 1217: */
! 1218: SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...);
! 1219:
! 1220: /*
! 1221: ** CAPI3REF: Memory Allocation Routines
! 1222: **
! 1223: ** An instance of this object defines the interface between SQLite
! 1224: ** and low-level memory allocation routines.
! 1225: **
! 1226: ** This object is used in only one place in the SQLite interface.
! 1227: ** A pointer to an instance of this object is the argument to
! 1228: ** [sqlite3_config()] when the configuration option is
! 1229: ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC].
! 1230: ** By creating an instance of this object
! 1231: ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])
! 1232: ** during configuration, an application can specify an alternative
! 1233: ** memory allocation subsystem for SQLite to use for all of its
! 1234: ** dynamic memory needs.
! 1235: **
! 1236: ** Note that SQLite comes with several [built-in memory allocators]
! 1237: ** that are perfectly adequate for the overwhelming majority of applications
! 1238: ** and that this object is only useful to a tiny minority of applications
! 1239: ** with specialized memory allocation requirements. This object is
! 1240: ** also used during testing of SQLite in order to specify an alternative
! 1241: ** memory allocator that simulates memory out-of-memory conditions in
! 1242: ** order to verify that SQLite recovers gracefully from such
! 1243: ** conditions.
! 1244: **
! 1245: ** The xMalloc, xRealloc, and xFree methods must work like the
! 1246: ** malloc(), realloc() and free() functions from the standard C library.
! 1247: ** ^SQLite guarantees that the second argument to
! 1248: ** xRealloc is always a value returned by a prior call to xRoundup.
! 1249: **
! 1250: ** xSize should return the allocated size of a memory allocation
! 1251: ** previously obtained from xMalloc or xRealloc. The allocated size
! 1252: ** is always at least as big as the requested size but may be larger.
! 1253: **
! 1254: ** The xRoundup method returns what would be the allocated size of
! 1255: ** a memory allocation given a particular requested size. Most memory
! 1256: ** allocators round up memory allocations at least to the next multiple
! 1257: ** of 8. Some allocators round up to a larger multiple or to a power of 2.
! 1258: ** Every memory allocation request coming in through [sqlite3_malloc()]
! 1259: ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0,
! 1260: ** that causes the corresponding memory allocation to fail.
! 1261: **
! 1262: ** The xInit method initializes the memory allocator. (For example,
! 1263: ** it might allocate any require mutexes or initialize internal data
! 1264: ** structures. The xShutdown method is invoked (indirectly) by
! 1265: ** [sqlite3_shutdown()] and should deallocate any resources acquired
! 1266: ** by xInit. The pAppData pointer is used as the only parameter to
! 1267: ** xInit and xShutdown.
! 1268: **
! 1269: ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes
! 1270: ** the xInit method, so the xInit method need not be threadsafe. The
! 1271: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
! 1272: ** not need to be threadsafe either. For all other methods, SQLite
! 1273: ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the
! 1274: ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which
! 1275: ** it is by default) and so the methods are automatically serialized.
! 1276: ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other
! 1277: ** methods must be threadsafe or else make their own arrangements for
! 1278: ** serialization.
! 1279: **
! 1280: ** SQLite will never invoke xInit() more than once without an intervening
! 1281: ** call to xShutdown().
! 1282: */
! 1283: typedef struct sqlite3_mem_methods sqlite3_mem_methods;
! 1284: struct sqlite3_mem_methods {
! 1285: void *(*xMalloc)(int); /* Memory allocation function */
! 1286: void (*xFree)(void*); /* Free a prior allocation */
! 1287: void *(*xRealloc)(void*,int); /* Resize an allocation */
! 1288: int (*xSize)(void*); /* Return the size of an allocation */
! 1289: int (*xRoundup)(int); /* Round up request size to allocation size */
! 1290: int (*xInit)(void*); /* Initialize the memory allocator */
! 1291: void (*xShutdown)(void*); /* Deinitialize the memory allocator */
! 1292: void *pAppData; /* Argument to xInit() and xShutdown() */
! 1293: };
! 1294:
! 1295: /*
! 1296: ** CAPI3REF: Configuration Options
! 1297: ** KEYWORDS: {configuration option}
! 1298: **
! 1299: ** These constants are the available integer configuration options that
! 1300: ** can be passed as the first argument to the [sqlite3_config()] interface.
! 1301: **
! 1302: ** New configuration options may be added in future releases of SQLite.
! 1303: ** Existing configuration options might be discontinued. Applications
! 1304: ** should check the return code from [sqlite3_config()] to make sure that
! 1305: ** the call worked. The [sqlite3_config()] interface will return a
! 1306: ** non-zero [error code] if a discontinued or unsupported configuration option
! 1307: ** is invoked.
! 1308: **
! 1309: ** <dl>
! 1310: ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>
! 1311: ** <dd>There are no arguments to this option. ^This option sets the
! 1312: ** [threading mode] to Single-thread. In other words, it disables
! 1313: ** all mutexing and puts SQLite into a mode where it can only be used
! 1314: ** by a single thread. ^If SQLite is compiled with
! 1315: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1316: ** it is not possible to change the [threading mode] from its default
! 1317: ** value of Single-thread and so [sqlite3_config()] will return
! 1318: ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD
! 1319: ** configuration option.</dd>
! 1320: **
! 1321: ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>
! 1322: ** <dd>There are no arguments to this option. ^This option sets the
! 1323: ** [threading mode] to Multi-thread. In other words, it disables
! 1324: ** mutexing on [database connection] and [prepared statement] objects.
! 1325: ** The application is responsible for serializing access to
! 1326: ** [database connections] and [prepared statements]. But other mutexes
! 1327: ** are enabled so that SQLite will be safe to use in a multi-threaded
! 1328: ** environment as long as no two threads attempt to use the same
! 1329: ** [database connection] at the same time. ^If SQLite is compiled with
! 1330: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1331: ** it is not possible to set the Multi-thread [threading mode] and
! 1332: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
! 1333: ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>
! 1334: **
! 1335: ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>
! 1336: ** <dd>There are no arguments to this option. ^This option sets the
! 1337: ** [threading mode] to Serialized. In other words, this option enables
! 1338: ** all mutexes including the recursive
! 1339: ** mutexes on [database connection] and [prepared statement] objects.
! 1340: ** In this mode (which is the default when SQLite is compiled with
! 1341: ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access
! 1342: ** to [database connections] and [prepared statements] so that the
! 1343: ** application is free to use the same [database connection] or the
! 1344: ** same [prepared statement] in different threads at the same time.
! 1345: ** ^If SQLite is compiled with
! 1346: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1347: ** it is not possible to set the Serialized [threading mode] and
! 1348: ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the
! 1349: ** SQLITE_CONFIG_SERIALIZED configuration option.</dd>
! 1350: **
! 1351: ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>
! 1352: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1353: ** instance of the [sqlite3_mem_methods] structure. The argument specifies
! 1354: ** alternative low-level memory allocation routines to be used in place of
! 1355: ** the memory allocation routines built into SQLite.)^ ^SQLite makes
! 1356: ** its own private copy of the content of the [sqlite3_mem_methods] structure
! 1357: ** before the [sqlite3_config()] call returns.</dd>
! 1358: **
! 1359: ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>
! 1360: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1361: ** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods]
! 1362: ** structure is filled with the currently defined memory allocation routines.)^
! 1363: ** This option can be used to overload the default memory allocation
! 1364: ** routines with a wrapper that simulations memory allocation failure or
! 1365: ** tracks memory usage, for example. </dd>
! 1366: **
! 1367: ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>
! 1368: ** <dd> ^This option takes single argument of type int, interpreted as a
! 1369: ** boolean, which enables or disables the collection of memory allocation
! 1370: ** statistics. ^(When memory allocation statistics are disabled, the
! 1371: ** following SQLite interfaces become non-operational:
! 1372: ** <ul>
! 1373: ** <li> [sqlite3_memory_used()]
! 1374: ** <li> [sqlite3_memory_highwater()]
! 1375: ** <li> [sqlite3_soft_heap_limit64()]
! 1376: ** <li> [sqlite3_status()]
! 1377: ** </ul>)^
! 1378: ** ^Memory allocation statistics are enabled by default unless SQLite is
! 1379: ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory
! 1380: ** allocation statistics are disabled by default.
! 1381: ** </dd>
! 1382: **
! 1383: ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>
! 1384: ** <dd> ^This option specifies a static memory buffer that SQLite can use for
! 1385: ** scratch memory. There are three arguments: A pointer an 8-byte
! 1386: ** aligned memory buffer from which the scratch allocations will be
! 1387: ** drawn, the size of each scratch allocation (sz),
! 1388: ** and the maximum number of scratch allocations (N). The sz
! 1389: ** argument must be a multiple of 16.
! 1390: ** The first argument must be a pointer to an 8-byte aligned buffer
! 1391: ** of at least sz*N bytes of memory.
! 1392: ** ^SQLite will use no more than two scratch buffers per thread. So
! 1393: ** N should be set to twice the expected maximum number of threads.
! 1394: ** ^SQLite will never require a scratch buffer that is more than 6
! 1395: ** times the database page size. ^If SQLite needs needs additional
! 1396: ** scratch memory beyond what is provided by this configuration option, then
! 1397: ** [sqlite3_malloc()] will be used to obtain the memory needed.</dd>
! 1398: **
! 1399: ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>
! 1400: ** <dd> ^This option specifies a static memory buffer that SQLite can use for
! 1401: ** the database page cache with the default page cache implementation.
! 1402: ** This configuration should not be used if an application-define page
! 1403: ** cache implementation is loaded using the SQLITE_CONFIG_PCACHE2 option.
! 1404: ** There are three arguments to this option: A pointer to 8-byte aligned
! 1405: ** memory, the size of each page buffer (sz), and the number of pages (N).
! 1406: ** The sz argument should be the size of the largest database page
! 1407: ** (a power of two between 512 and 32768) plus a little extra for each
! 1408: ** page header. ^The page header size is 20 to 40 bytes depending on
! 1409: ** the host architecture. ^It is harmless, apart from the wasted memory,
! 1410: ** to make sz a little too large. The first
! 1411: ** argument should point to an allocation of at least sz*N bytes of memory.
! 1412: ** ^SQLite will use the memory provided by the first argument to satisfy its
! 1413: ** memory needs for the first N pages that it adds to cache. ^If additional
! 1414: ** page cache memory is needed beyond what is provided by this option, then
! 1415: ** SQLite goes to [sqlite3_malloc()] for the additional storage space.
! 1416: ** The pointer in the first argument must
! 1417: ** be aligned to an 8-byte boundary or subsequent behavior of SQLite
! 1418: ** will be undefined.</dd>
! 1419: **
! 1420: ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>
! 1421: ** <dd> ^This option specifies a static memory buffer that SQLite will use
! 1422: ** for all of its dynamic memory allocation needs beyond those provided
! 1423: ** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE].
! 1424: ** There are three arguments: An 8-byte aligned pointer to the memory,
! 1425: ** the number of bytes in the memory buffer, and the minimum allocation size.
! 1426: ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts
! 1427: ** to using its default memory allocator (the system malloc() implementation),
! 1428: ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the
! 1429: ** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or
! 1430: ** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory
! 1431: ** allocator is engaged to handle all of SQLites memory allocation needs.
! 1432: ** The first pointer (the memory pointer) must be aligned to an 8-byte
! 1433: ** boundary or subsequent behavior of SQLite will be undefined.
! 1434: ** The minimum allocation size is capped at 2**12. Reasonable values
! 1435: ** for the minimum allocation size are 2**5 through 2**8.</dd>
! 1436: **
! 1437: ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>
! 1438: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1439: ** instance of the [sqlite3_mutex_methods] structure. The argument specifies
! 1440: ** alternative low-level mutex routines to be used in place
! 1441: ** the mutex routines built into SQLite.)^ ^SQLite makes a copy of the
! 1442: ** content of the [sqlite3_mutex_methods] structure before the call to
! 1443: ** [sqlite3_config()] returns. ^If SQLite is compiled with
! 1444: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1445: ** the entire mutexing subsystem is omitted from the build and hence calls to
! 1446: ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will
! 1447: ** return [SQLITE_ERROR].</dd>
! 1448: **
! 1449: ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>
! 1450: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1451: ** instance of the [sqlite3_mutex_methods] structure. The
! 1452: ** [sqlite3_mutex_methods]
! 1453: ** structure is filled with the currently defined mutex routines.)^
! 1454: ** This option can be used to overload the default mutex allocation
! 1455: ** routines with a wrapper used to track mutex usage for performance
! 1456: ** profiling or testing, for example. ^If SQLite is compiled with
! 1457: ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then
! 1458: ** the entire mutexing subsystem is omitted from the build and hence calls to
! 1459: ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will
! 1460: ** return [SQLITE_ERROR].</dd>
! 1461: **
! 1462: ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>
! 1463: ** <dd> ^(This option takes two arguments that determine the default
! 1464: ** memory allocation for the lookaside memory allocator on each
! 1465: ** [database connection]. The first argument is the
! 1466: ** size of each lookaside buffer slot and the second is the number of
! 1467: ** slots allocated to each database connection.)^ ^(This option sets the
! 1468: ** <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]
! 1469: ** verb to [sqlite3_db_config()] can be used to change the lookaside
! 1470: ** configuration on individual connections.)^ </dd>
! 1471: **
! 1472: ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>
! 1473: ** <dd> ^(This option takes a single argument which is a pointer to
! 1474: ** an [sqlite3_pcache_methods2] object. This object specifies the interface
! 1475: ** to a custom page cache implementation.)^ ^SQLite makes a copy of the
! 1476: ** object and uses it for page cache memory allocations.</dd>
! 1477: **
! 1478: ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>
! 1479: ** <dd> ^(This option takes a single argument which is a pointer to an
! 1480: ** [sqlite3_pcache_methods2] object. SQLite copies of the current
! 1481: ** page cache implementation into that object.)^ </dd>
! 1482: **
! 1483: ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
! 1484: ** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
! 1485: ** function with a call signature of void(*)(void*,int,const char*),
! 1486: ** and a pointer to void. ^If the function pointer is not NULL, it is
! 1487: ** invoked by [sqlite3_log()] to process each logging event. ^If the
! 1488: ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.
! 1489: ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is
! 1490: ** passed through as the first parameter to the application-defined logger
! 1491: ** function whenever that function is invoked. ^The second parameter to
! 1492: ** the logger function is a copy of the first parameter to the corresponding
! 1493: ** [sqlite3_log()] call and is intended to be a [result code] or an
! 1494: ** [extended result code]. ^The third parameter passed to the logger is
! 1495: ** log message after formatting via [sqlite3_snprintf()].
! 1496: ** The SQLite logging interface is not reentrant; the logger function
! 1497: ** supplied by the application must not invoke any SQLite interface.
! 1498: ** In a multi-threaded application, the application-defined logger
! 1499: ** function must be threadsafe. </dd>
! 1500: **
! 1501: ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI
! 1502: ** <dd> This option takes a single argument of type int. If non-zero, then
! 1503: ** URI handling is globally enabled. If the parameter is zero, then URI handling
! 1504: ** is globally disabled. If URI handling is globally enabled, all filenames
! 1505: ** passed to [sqlite3_open()], [sqlite3_open_v2()], [sqlite3_open16()] or
! 1506: ** specified as part of [ATTACH] commands are interpreted as URIs, regardless
! 1507: ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database
! 1508: ** connection is opened. If it is globally disabled, filenames are
! 1509: ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the
! 1510: ** database connection is opened. By default, URI handling is globally
! 1511: ** disabled. The default value may be changed by compiling with the
! 1512: ** [SQLITE_USE_URI] symbol defined.
! 1513: **
! 1514: ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
! 1515: ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFNIG_GETPCACHE
! 1516: ** <dd> These options are obsolete and should not be used by new code.
! 1517: ** They are retained for backwards compatibility but are now no-ops.
! 1518: ** </dl>
! 1519: */
! 1520: #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */
! 1521: #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */
! 1522: #define SQLITE_CONFIG_SERIALIZED 3 /* nil */
! 1523: #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */
! 1524: #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */
! 1525: #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */
! 1526: #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */
! 1527: #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */
! 1528: #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */
! 1529: #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */
! 1530: #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */
! 1531: /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
! 1532: #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */
! 1533: #define SQLITE_CONFIG_PCACHE 14 /* no-op */
! 1534: #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */
! 1535: #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */
! 1536: #define SQLITE_CONFIG_URI 17 /* int */
! 1537: #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */
! 1538: #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */
! 1539:
! 1540: /*
! 1541: ** CAPI3REF: Database Connection Configuration Options
! 1542: **
! 1543: ** These constants are the available integer configuration options that
! 1544: ** can be passed as the second argument to the [sqlite3_db_config()] interface.
! 1545: **
! 1546: ** New configuration options may be added in future releases of SQLite.
! 1547: ** Existing configuration options might be discontinued. Applications
! 1548: ** should check the return code from [sqlite3_db_config()] to make sure that
! 1549: ** the call worked. ^The [sqlite3_db_config()] interface will return a
! 1550: ** non-zero [error code] if a discontinued or unsupported configuration option
! 1551: ** is invoked.
! 1552: **
! 1553: ** <dl>
! 1554: ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>
! 1555: ** <dd> ^This option takes three additional arguments that determine the
! 1556: ** [lookaside memory allocator] configuration for the [database connection].
! 1557: ** ^The first argument (the third parameter to [sqlite3_db_config()] is a
! 1558: ** pointer to a memory buffer to use for lookaside memory.
! 1559: ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb
! 1560: ** may be NULL in which case SQLite will allocate the
! 1561: ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the
! 1562: ** size of each lookaside buffer slot. ^The third argument is the number of
! 1563: ** slots. The size of the buffer in the first argument must be greater than
! 1564: ** or equal to the product of the second and third arguments. The buffer
! 1565: ** must be aligned to an 8-byte boundary. ^If the second argument to
! 1566: ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally
! 1567: ** rounded down to the next smaller multiple of 8. ^(The lookaside memory
! 1568: ** configuration for a database connection can only be changed when that
! 1569: ** connection is not currently using lookaside memory, or in other words
! 1570: ** when the "current value" returned by
! 1571: ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.
! 1572: ** Any attempt to change the lookaside memory configuration when lookaside
! 1573: ** memory is in use leaves the configuration unchanged and returns
! 1574: ** [SQLITE_BUSY].)^</dd>
! 1575: **
! 1576: ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>
! 1577: ** <dd> ^This option is used to enable or disable the enforcement of
! 1578: ** [foreign key constraints]. There should be two additional arguments.
! 1579: ** The first argument is an integer which is 0 to disable FK enforcement,
! 1580: ** positive to enable FK enforcement or negative to leave FK enforcement
! 1581: ** unchanged. The second parameter is a pointer to an integer into which
! 1582: ** is written 0 or 1 to indicate whether FK enforcement is off or on
! 1583: ** following this call. The second parameter may be a NULL pointer, in
! 1584: ** which case the FK enforcement setting is not reported back. </dd>
! 1585: **
! 1586: ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>
! 1587: ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].
! 1588: ** There should be two additional arguments.
! 1589: ** The first argument is an integer which is 0 to disable triggers,
! 1590: ** positive to enable triggers or negative to leave the setting unchanged.
! 1591: ** The second parameter is a pointer to an integer into which
! 1592: ** is written 0 or 1 to indicate whether triggers are disabled or enabled
! 1593: ** following this call. The second parameter may be a NULL pointer, in
! 1594: ** which case the trigger setting is not reported back. </dd>
! 1595: **
! 1596: ** </dl>
! 1597: */
! 1598: #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */
! 1599: #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */
! 1600: #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */
! 1601:
! 1602:
! 1603: /*
! 1604: ** CAPI3REF: Enable Or Disable Extended Result Codes
! 1605: **
! 1606: ** ^The sqlite3_extended_result_codes() routine enables or disables the
! 1607: ** [extended result codes] feature of SQLite. ^The extended result
! 1608: ** codes are disabled by default for historical compatibility.
! 1609: */
! 1610: SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff);
! 1611:
! 1612: /*
! 1613: ** CAPI3REF: Last Insert Rowid
! 1614: **
! 1615: ** ^Each entry in an SQLite table has a unique 64-bit signed
! 1616: ** integer key called the [ROWID | "rowid"]. ^The rowid is always available
! 1617: ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
! 1618: ** names are not also used by explicitly declared columns. ^If
! 1619: ** the table has a column of type [INTEGER PRIMARY KEY] then that column
! 1620: ** is another alias for the rowid.
! 1621: **
! 1622: ** ^This routine returns the [rowid] of the most recent
! 1623: ** successful [INSERT] into the database from the [database connection]
! 1624: ** in the first argument. ^As of SQLite version 3.7.7, this routines
! 1625: ** records the last insert rowid of both ordinary tables and [virtual tables].
! 1626: ** ^If no successful [INSERT]s
! 1627: ** have ever occurred on that database connection, zero is returned.
! 1628: **
! 1629: ** ^(If an [INSERT] occurs within a trigger or within a [virtual table]
! 1630: ** method, then this routine will return the [rowid] of the inserted
! 1631: ** row as long as the trigger or virtual table method is running.
! 1632: ** But once the trigger or virtual table method ends, the value returned
! 1633: ** by this routine reverts to what it was before the trigger or virtual
! 1634: ** table method began.)^
! 1635: **
! 1636: ** ^An [INSERT] that fails due to a constraint violation is not a
! 1637: ** successful [INSERT] and does not change the value returned by this
! 1638: ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
! 1639: ** and INSERT OR ABORT make no changes to the return value of this
! 1640: ** routine when their insertion fails. ^(When INSERT OR REPLACE
! 1641: ** encounters a constraint violation, it does not fail. The
! 1642: ** INSERT continues to completion after deleting rows that caused
! 1643: ** the constraint problem so INSERT OR REPLACE will always change
! 1644: ** the return value of this interface.)^
! 1645: **
! 1646: ** ^For the purposes of this routine, an [INSERT] is considered to
! 1647: ** be successful even if it is subsequently rolled back.
! 1648: **
! 1649: ** This function is accessible to SQL statements via the
! 1650: ** [last_insert_rowid() SQL function].
! 1651: **
! 1652: ** If a separate thread performs a new [INSERT] on the same
! 1653: ** database connection while the [sqlite3_last_insert_rowid()]
! 1654: ** function is running and thus changes the last insert [rowid],
! 1655: ** then the value returned by [sqlite3_last_insert_rowid()] is
! 1656: ** unpredictable and might not equal either the old or the new
! 1657: ** last insert [rowid].
! 1658: */
! 1659: SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);
! 1660:
! 1661: /*
! 1662: ** CAPI3REF: Count The Number Of Rows Modified
! 1663: **
! 1664: ** ^This function returns the number of database rows that were changed
! 1665: ** or inserted or deleted by the most recently completed SQL statement
! 1666: ** on the [database connection] specified by the first parameter.
! 1667: ** ^(Only changes that are directly specified by the [INSERT], [UPDATE],
! 1668: ** or [DELETE] statement are counted. Auxiliary changes caused by
! 1669: ** triggers or [foreign key actions] are not counted.)^ Use the
! 1670: ** [sqlite3_total_changes()] function to find the total number of changes
! 1671: ** including changes caused by triggers and foreign key actions.
! 1672: **
! 1673: ** ^Changes to a view that are simulated by an [INSTEAD OF trigger]
! 1674: ** are not counted. Only real table changes are counted.
! 1675: **
! 1676: ** ^(A "row change" is a change to a single row of a single table
! 1677: ** caused by an INSERT, DELETE, or UPDATE statement. Rows that
! 1678: ** are changed as side effects of [REPLACE] constraint resolution,
! 1679: ** rollback, ABORT processing, [DROP TABLE], or by any other
! 1680: ** mechanisms do not count as direct row changes.)^
! 1681: **
! 1682: ** A "trigger context" is a scope of execution that begins and
! 1683: ** ends with the script of a [CREATE TRIGGER | trigger].
! 1684: ** Most SQL statements are
! 1685: ** evaluated outside of any trigger. This is the "top level"
! 1686: ** trigger context. If a trigger fires from the top level, a
! 1687: ** new trigger context is entered for the duration of that one
! 1688: ** trigger. Subtriggers create subcontexts for their duration.
! 1689: **
! 1690: ** ^Calling [sqlite3_exec()] or [sqlite3_step()] recursively does
! 1691: ** not create a new trigger context.
! 1692: **
! 1693: ** ^This function returns the number of direct row changes in the
! 1694: ** most recent INSERT, UPDATE, or DELETE statement within the same
! 1695: ** trigger context.
! 1696: **
! 1697: ** ^Thus, when called from the top level, this function returns the
! 1698: ** number of changes in the most recent INSERT, UPDATE, or DELETE
! 1699: ** that also occurred at the top level. ^(Within the body of a trigger,
! 1700: ** the sqlite3_changes() interface can be called to find the number of
! 1701: ** changes in the most recently completed INSERT, UPDATE, or DELETE
! 1702: ** statement within the body of the same trigger.
! 1703: ** However, the number returned does not include changes
! 1704: ** caused by subtriggers since those have their own context.)^
! 1705: **
! 1706: ** See also the [sqlite3_total_changes()] interface, the
! 1707: ** [count_changes pragma], and the [changes() SQL function].
! 1708: **
! 1709: ** If a separate thread makes changes on the same database connection
! 1710: ** while [sqlite3_changes()] is running then the value returned
! 1711: ** is unpredictable and not meaningful.
! 1712: */
! 1713: SQLITE_API int sqlite3_changes(sqlite3*);
! 1714:
! 1715: /*
! 1716: ** CAPI3REF: Total Number Of Rows Modified
! 1717: **
! 1718: ** ^This function returns the number of row changes caused by [INSERT],
! 1719: ** [UPDATE] or [DELETE] statements since the [database connection] was opened.
! 1720: ** ^(The count returned by sqlite3_total_changes() includes all changes
! 1721: ** from all [CREATE TRIGGER | trigger] contexts and changes made by
! 1722: ** [foreign key actions]. However,
! 1723: ** the count does not include changes used to implement [REPLACE] constraints,
! 1724: ** do rollbacks or ABORT processing, or [DROP TABLE] processing. The
! 1725: ** count does not include rows of views that fire an [INSTEAD OF trigger],
! 1726: ** though if the INSTEAD OF trigger makes changes of its own, those changes
! 1727: ** are counted.)^
! 1728: ** ^The sqlite3_total_changes() function counts the changes as soon as
! 1729: ** the statement that makes them is completed (when the statement handle
! 1730: ** is passed to [sqlite3_reset()] or [sqlite3_finalize()]).
! 1731: **
! 1732: ** See also the [sqlite3_changes()] interface, the
! 1733: ** [count_changes pragma], and the [total_changes() SQL function].
! 1734: **
! 1735: ** If a separate thread makes changes on the same database connection
! 1736: ** while [sqlite3_total_changes()] is running then the value
! 1737: ** returned is unpredictable and not meaningful.
! 1738: */
! 1739: SQLITE_API int sqlite3_total_changes(sqlite3*);
! 1740:
! 1741: /*
! 1742: ** CAPI3REF: Interrupt A Long-Running Query
! 1743: **
! 1744: ** ^This function causes any pending database operation to abort and
! 1745: ** return at its earliest opportunity. This routine is typically
! 1746: ** called in response to a user action such as pressing "Cancel"
! 1747: ** or Ctrl-C where the user wants a long query operation to halt
! 1748: ** immediately.
! 1749: **
! 1750: ** ^It is safe to call this routine from a thread different from the
! 1751: ** thread that is currently running the database operation. But it
! 1752: ** is not safe to call this routine with a [database connection] that
! 1753: ** is closed or might close before sqlite3_interrupt() returns.
! 1754: **
! 1755: ** ^If an SQL operation is very nearly finished at the time when
! 1756: ** sqlite3_interrupt() is called, then it might not have an opportunity
! 1757: ** to be interrupted and might continue to completion.
! 1758: **
! 1759: ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].
! 1760: ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE
! 1761: ** that is inside an explicit transaction, then the entire transaction
! 1762: ** will be rolled back automatically.
! 1763: **
! 1764: ** ^The sqlite3_interrupt(D) call is in effect until all currently running
! 1765: ** SQL statements on [database connection] D complete. ^Any new SQL statements
! 1766: ** that are started after the sqlite3_interrupt() call and before the
! 1767: ** running statements reaches zero are interrupted as if they had been
! 1768: ** running prior to the sqlite3_interrupt() call. ^New SQL statements
! 1769: ** that are started after the running statement count reaches zero are
! 1770: ** not effected by the sqlite3_interrupt().
! 1771: ** ^A call to sqlite3_interrupt(D) that occurs when there are no running
! 1772: ** SQL statements is a no-op and has no effect on SQL statements
! 1773: ** that are started after the sqlite3_interrupt() call returns.
! 1774: **
! 1775: ** If the database connection closes while [sqlite3_interrupt()]
! 1776: ** is running then bad things will likely happen.
! 1777: */
! 1778: SQLITE_API void sqlite3_interrupt(sqlite3*);
! 1779:
! 1780: /*
! 1781: ** CAPI3REF: Determine If An SQL Statement Is Complete
! 1782: **
! 1783: ** These routines are useful during command-line input to determine if the
! 1784: ** currently entered text seems to form a complete SQL statement or
! 1785: ** if additional input is needed before sending the text into
! 1786: ** SQLite for parsing. ^These routines return 1 if the input string
! 1787: ** appears to be a complete SQL statement. ^A statement is judged to be
! 1788: ** complete if it ends with a semicolon token and is not a prefix of a
! 1789: ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within
! 1790: ** string literals or quoted identifier names or comments are not
! 1791: ** independent tokens (they are part of the token in which they are
! 1792: ** embedded) and thus do not count as a statement terminator. ^Whitespace
! 1793: ** and comments that follow the final semicolon are ignored.
! 1794: **
! 1795: ** ^These routines return 0 if the statement is incomplete. ^If a
! 1796: ** memory allocation fails, then SQLITE_NOMEM is returned.
! 1797: **
! 1798: ** ^These routines do not parse the SQL statements thus
! 1799: ** will not detect syntactically incorrect SQL.
! 1800: **
! 1801: ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior
! 1802: ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked
! 1803: ** automatically by sqlite3_complete16(). If that initialization fails,
! 1804: ** then the return value from sqlite3_complete16() will be non-zero
! 1805: ** regardless of whether or not the input SQL is complete.)^
! 1806: **
! 1807: ** The input to [sqlite3_complete()] must be a zero-terminated
! 1808: ** UTF-8 string.
! 1809: **
! 1810: ** The input to [sqlite3_complete16()] must be a zero-terminated
! 1811: ** UTF-16 string in native byte order.
! 1812: */
! 1813: SQLITE_API int sqlite3_complete(const char *sql);
! 1814: SQLITE_API int sqlite3_complete16(const void *sql);
! 1815:
! 1816: /*
! 1817: ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors
! 1818: **
! 1819: ** ^This routine sets a callback function that might be invoked whenever
! 1820: ** an attempt is made to open a database table that another thread
! 1821: ** or process has locked.
! 1822: **
! 1823: ** ^If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]
! 1824: ** is returned immediately upon encountering the lock. ^If the busy callback
! 1825: ** is not NULL, then the callback might be invoked with two arguments.
! 1826: **
! 1827: ** ^The first argument to the busy handler is a copy of the void* pointer which
! 1828: ** is the third argument to sqlite3_busy_handler(). ^The second argument to
! 1829: ** the busy handler callback is the number of times that the busy handler has
! 1830: ** been invoked for this locking event. ^If the
! 1831: ** busy callback returns 0, then no additional attempts are made to
! 1832: ** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned.
! 1833: ** ^If the callback returns non-zero, then another attempt
! 1834: ** is made to open the database for reading and the cycle repeats.
! 1835: **
! 1836: ** The presence of a busy handler does not guarantee that it will be invoked
! 1837: ** when there is lock contention. ^If SQLite determines that invoking the busy
! 1838: ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]
! 1839: ** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler.
! 1840: ** Consider a scenario where one process is holding a read lock that
! 1841: ** it is trying to promote to a reserved lock and
! 1842: ** a second process is holding a reserved lock that it is trying
! 1843: ** to promote to an exclusive lock. The first process cannot proceed
! 1844: ** because it is blocked by the second and the second process cannot
! 1845: ** proceed because it is blocked by the first. If both processes
! 1846: ** invoke the busy handlers, neither will make any progress. Therefore,
! 1847: ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this
! 1848: ** will induce the first process to release its read lock and allow
! 1849: ** the second process to proceed.
! 1850: **
! 1851: ** ^The default busy callback is NULL.
! 1852: **
! 1853: ** ^The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED]
! 1854: ** when SQLite is in the middle of a large transaction where all the
! 1855: ** changes will not fit into the in-memory cache. SQLite will
! 1856: ** already hold a RESERVED lock on the database file, but it needs
! 1857: ** to promote this lock to EXCLUSIVE so that it can spill cache
! 1858: ** pages into the database file without harm to concurrent
! 1859: ** readers. ^If it is unable to promote the lock, then the in-memory
! 1860: ** cache will be left in an inconsistent state and so the error
! 1861: ** code is promoted from the relatively benign [SQLITE_BUSY] to
! 1862: ** the more severe [SQLITE_IOERR_BLOCKED]. ^This error code promotion
! 1863: ** forces an automatic rollback of the changes. See the
! 1864: ** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError">
! 1865: ** CorruptionFollowingBusyError</a> wiki page for a discussion of why
! 1866: ** this is important.
! 1867: **
! 1868: ** ^(There can only be a single busy handler defined for each
! 1869: ** [database connection]. Setting a new busy handler clears any
! 1870: ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]
! 1871: ** will also set or clear the busy handler.
! 1872: **
! 1873: ** The busy callback should not take any actions which modify the
! 1874: ** database connection that invoked the busy handler. Any such actions
! 1875: ** result in undefined behavior.
! 1876: **
! 1877: ** A busy handler must not close the database connection
! 1878: ** or [prepared statement] that invoked the busy handler.
! 1879: */
! 1880: SQLITE_API int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*);
! 1881:
! 1882: /*
! 1883: ** CAPI3REF: Set A Busy Timeout
! 1884: **
! 1885: ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps
! 1886: ** for a specified amount of time when a table is locked. ^The handler
! 1887: ** will sleep multiple times until at least "ms" milliseconds of sleeping
! 1888: ** have accumulated. ^After at least "ms" milliseconds of sleeping,
! 1889: ** the handler returns 0 which causes [sqlite3_step()] to return
! 1890: ** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED].
! 1891: **
! 1892: ** ^Calling this routine with an argument less than or equal to zero
! 1893: ** turns off all busy handlers.
! 1894: **
! 1895: ** ^(There can only be a single busy handler for a particular
! 1896: ** [database connection] any any given moment. If another busy handler
! 1897: ** was defined (using [sqlite3_busy_handler()]) prior to calling
! 1898: ** this routine, that other busy handler is cleared.)^
! 1899: */
! 1900: SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms);
! 1901:
! 1902: /*
! 1903: ** CAPI3REF: Convenience Routines For Running Queries
! 1904: **
! 1905: ** This is a legacy interface that is preserved for backwards compatibility.
! 1906: ** Use of this interface is not recommended.
! 1907: **
! 1908: ** Definition: A <b>result table</b> is memory data structure created by the
! 1909: ** [sqlite3_get_table()] interface. A result table records the
! 1910: ** complete query results from one or more queries.
! 1911: **
! 1912: ** The table conceptually has a number of rows and columns. But
! 1913: ** these numbers are not part of the result table itself. These
! 1914: ** numbers are obtained separately. Let N be the number of rows
! 1915: ** and M be the number of columns.
! 1916: **
! 1917: ** A result table is an array of pointers to zero-terminated UTF-8 strings.
! 1918: ** There are (N+1)*M elements in the array. The first M pointers point
! 1919: ** to zero-terminated strings that contain the names of the columns.
! 1920: ** The remaining entries all point to query results. NULL values result
! 1921: ** in NULL pointers. All other values are in their UTF-8 zero-terminated
! 1922: ** string representation as returned by [sqlite3_column_text()].
! 1923: **
! 1924: ** A result table might consist of one or more memory allocations.
! 1925: ** It is not safe to pass a result table directly to [sqlite3_free()].
! 1926: ** A result table should be deallocated using [sqlite3_free_table()].
! 1927: **
! 1928: ** ^(As an example of the result table format, suppose a query result
! 1929: ** is as follows:
! 1930: **
! 1931: ** <blockquote><pre>
! 1932: ** Name | Age
! 1933: ** -----------------------
! 1934: ** Alice | 43
! 1935: ** Bob | 28
! 1936: ** Cindy | 21
! 1937: ** </pre></blockquote>
! 1938: **
! 1939: ** There are two column (M==2) and three rows (N==3). Thus the
! 1940: ** result table has 8 entries. Suppose the result table is stored
! 1941: ** in an array names azResult. Then azResult holds this content:
! 1942: **
! 1943: ** <blockquote><pre>
! 1944: ** azResult[0] = "Name";
! 1945: ** azResult[1] = "Age";
! 1946: ** azResult[2] = "Alice";
! 1947: ** azResult[3] = "43";
! 1948: ** azResult[4] = "Bob";
! 1949: ** azResult[5] = "28";
! 1950: ** azResult[6] = "Cindy";
! 1951: ** azResult[7] = "21";
! 1952: ** </pre></blockquote>)^
! 1953: **
! 1954: ** ^The sqlite3_get_table() function evaluates one or more
! 1955: ** semicolon-separated SQL statements in the zero-terminated UTF-8
! 1956: ** string of its 2nd parameter and returns a result table to the
! 1957: ** pointer given in its 3rd parameter.
! 1958: **
! 1959: ** After the application has finished with the result from sqlite3_get_table(),
! 1960: ** it must pass the result table pointer to sqlite3_free_table() in order to
! 1961: ** release the memory that was malloced. Because of the way the
! 1962: ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling
! 1963: ** function must not try to call [sqlite3_free()] directly. Only
! 1964: ** [sqlite3_free_table()] is able to release the memory properly and safely.
! 1965: **
! 1966: ** The sqlite3_get_table() interface is implemented as a wrapper around
! 1967: ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access
! 1968: ** to any internal data structures of SQLite. It uses only the public
! 1969: ** interface defined here. As a consequence, errors that occur in the
! 1970: ** wrapper layer outside of the internal [sqlite3_exec()] call are not
! 1971: ** reflected in subsequent calls to [sqlite3_errcode()] or
! 1972: ** [sqlite3_errmsg()].
! 1973: */
! 1974: SQLITE_API int sqlite3_get_table(
! 1975: sqlite3 *db, /* An open database */
! 1976: const char *zSql, /* SQL to be evaluated */
! 1977: char ***pazResult, /* Results of the query */
! 1978: int *pnRow, /* Number of result rows written here */
! 1979: int *pnColumn, /* Number of result columns written here */
! 1980: char **pzErrmsg /* Error msg written here */
! 1981: );
! 1982: SQLITE_API void sqlite3_free_table(char **result);
! 1983:
! 1984: /*
! 1985: ** CAPI3REF: Formatted String Printing Functions
! 1986: **
! 1987: ** These routines are work-alikes of the "printf()" family of functions
! 1988: ** from the standard C library.
! 1989: **
! 1990: ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their
! 1991: ** results into memory obtained from [sqlite3_malloc()].
! 1992: ** The strings returned by these two routines should be
! 1993: ** released by [sqlite3_free()]. ^Both routines return a
! 1994: ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough
! 1995: ** memory to hold the resulting string.
! 1996: **
! 1997: ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from
! 1998: ** the standard C library. The result is written into the
! 1999: ** buffer supplied as the second parameter whose size is given by
! 2000: ** the first parameter. Note that the order of the
! 2001: ** first two parameters is reversed from snprintf().)^ This is an
! 2002: ** historical accident that cannot be fixed without breaking
! 2003: ** backwards compatibility. ^(Note also that sqlite3_snprintf()
! 2004: ** returns a pointer to its buffer instead of the number of
! 2005: ** characters actually written into the buffer.)^ We admit that
! 2006: ** the number of characters written would be a more useful return
! 2007: ** value but we cannot change the implementation of sqlite3_snprintf()
! 2008: ** now without breaking compatibility.
! 2009: **
! 2010: ** ^As long as the buffer size is greater than zero, sqlite3_snprintf()
! 2011: ** guarantees that the buffer is always zero-terminated. ^The first
! 2012: ** parameter "n" is the total size of the buffer, including space for
! 2013: ** the zero terminator. So the longest string that can be completely
! 2014: ** written will be n-1 characters.
! 2015: **
! 2016: ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().
! 2017: **
! 2018: ** These routines all implement some additional formatting
! 2019: ** options that are useful for constructing SQL statements.
! 2020: ** All of the usual printf() formatting options apply. In addition, there
! 2021: ** is are "%q", "%Q", and "%z" options.
! 2022: **
! 2023: ** ^(The %q option works like %s in that it substitutes a nul-terminated
! 2024: ** string from the argument list. But %q also doubles every '\'' character.
! 2025: ** %q is designed for use inside a string literal.)^ By doubling each '\''
! 2026: ** character it escapes that character and allows it to be inserted into
! 2027: ** the string.
! 2028: **
! 2029: ** For example, assume the string variable zText contains text as follows:
! 2030: **
! 2031: ** <blockquote><pre>
! 2032: ** char *zText = "It's a happy day!";
! 2033: ** </pre></blockquote>
! 2034: **
! 2035: ** One can use this text in an SQL statement as follows:
! 2036: **
! 2037: ** <blockquote><pre>
! 2038: ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);
! 2039: ** sqlite3_exec(db, zSQL, 0, 0, 0);
! 2040: ** sqlite3_free(zSQL);
! 2041: ** </pre></blockquote>
! 2042: **
! 2043: ** Because the %q format string is used, the '\'' character in zText
! 2044: ** is escaped and the SQL generated is as follows:
! 2045: **
! 2046: ** <blockquote><pre>
! 2047: ** INSERT INTO table1 VALUES('It''s a happy day!')
! 2048: ** </pre></blockquote>
! 2049: **
! 2050: ** This is correct. Had we used %s instead of %q, the generated SQL
! 2051: ** would have looked like this:
! 2052: **
! 2053: ** <blockquote><pre>
! 2054: ** INSERT INTO table1 VALUES('It's a happy day!');
! 2055: ** </pre></blockquote>
! 2056: **
! 2057: ** This second example is an SQL syntax error. As a general rule you should
! 2058: ** always use %q instead of %s when inserting text into a string literal.
! 2059: **
! 2060: ** ^(The %Q option works like %q except it also adds single quotes around
! 2061: ** the outside of the total string. Additionally, if the parameter in the
! 2062: ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without
! 2063: ** single quotes).)^ So, for example, one could say:
! 2064: **
! 2065: ** <blockquote><pre>
! 2066: ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
! 2067: ** sqlite3_exec(db, zSQL, 0, 0, 0);
! 2068: ** sqlite3_free(zSQL);
! 2069: ** </pre></blockquote>
! 2070: **
! 2071: ** The code above will render a correct SQL statement in the zSQL
! 2072: ** variable even if the zText variable is a NULL pointer.
! 2073: **
! 2074: ** ^(The "%z" formatting option works like "%s" but with the
! 2075: ** addition that after the string has been read and copied into
! 2076: ** the result, [sqlite3_free()] is called on the input string.)^
! 2077: */
! 2078: SQLITE_API char *sqlite3_mprintf(const char*,...);
! 2079: SQLITE_API char *sqlite3_vmprintf(const char*, va_list);
! 2080: SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...);
! 2081: SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list);
! 2082:
! 2083: /*
! 2084: ** CAPI3REF: Memory Allocation Subsystem
! 2085: **
! 2086: ** The SQLite core uses these three routines for all of its own
! 2087: ** internal memory allocation needs. "Core" in the previous sentence
! 2088: ** does not include operating-system specific VFS implementation. The
! 2089: ** Windows VFS uses native malloc() and free() for some operations.
! 2090: **
! 2091: ** ^The sqlite3_malloc() routine returns a pointer to a block
! 2092: ** of memory at least N bytes in length, where N is the parameter.
! 2093: ** ^If sqlite3_malloc() is unable to obtain sufficient free
! 2094: ** memory, it returns a NULL pointer. ^If the parameter N to
! 2095: ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns
! 2096: ** a NULL pointer.
! 2097: **
! 2098: ** ^Calling sqlite3_free() with a pointer previously returned
! 2099: ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so
! 2100: ** that it might be reused. ^The sqlite3_free() routine is
! 2101: ** a no-op if is called with a NULL pointer. Passing a NULL pointer
! 2102: ** to sqlite3_free() is harmless. After being freed, memory
! 2103: ** should neither be read nor written. Even reading previously freed
! 2104: ** memory might result in a segmentation fault or other severe error.
! 2105: ** Memory corruption, a segmentation fault, or other severe error
! 2106: ** might result if sqlite3_free() is called with a non-NULL pointer that
! 2107: ** was not obtained from sqlite3_malloc() or sqlite3_realloc().
! 2108: **
! 2109: ** ^(The sqlite3_realloc() interface attempts to resize a
! 2110: ** prior memory allocation to be at least N bytes, where N is the
! 2111: ** second parameter. The memory allocation to be resized is the first
! 2112: ** parameter.)^ ^ If the first parameter to sqlite3_realloc()
! 2113: ** is a NULL pointer then its behavior is identical to calling
! 2114: ** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc().
! 2115: ** ^If the second parameter to sqlite3_realloc() is zero or
! 2116: ** negative then the behavior is exactly the same as calling
! 2117: ** sqlite3_free(P) where P is the first parameter to sqlite3_realloc().
! 2118: ** ^sqlite3_realloc() returns a pointer to a memory allocation
! 2119: ** of at least N bytes in size or NULL if sufficient memory is unavailable.
! 2120: ** ^If M is the size of the prior allocation, then min(N,M) bytes
! 2121: ** of the prior allocation are copied into the beginning of buffer returned
! 2122: ** by sqlite3_realloc() and the prior allocation is freed.
! 2123: ** ^If sqlite3_realloc() returns NULL, then the prior allocation
! 2124: ** is not freed.
! 2125: **
! 2126: ** ^The memory returned by sqlite3_malloc() and sqlite3_realloc()
! 2127: ** is always aligned to at least an 8 byte boundary, or to a
! 2128: ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time
! 2129: ** option is used.
! 2130: **
! 2131: ** In SQLite version 3.5.0 and 3.5.1, it was possible to define
! 2132: ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in
! 2133: ** implementation of these routines to be omitted. That capability
! 2134: ** is no longer provided. Only built-in memory allocators can be used.
! 2135: **
! 2136: ** The Windows OS interface layer calls
! 2137: ** the system malloc() and free() directly when converting
! 2138: ** filenames between the UTF-8 encoding used by SQLite
! 2139: ** and whatever filename encoding is used by the particular Windows
! 2140: ** installation. Memory allocation errors are detected, but
! 2141: ** they are reported back as [SQLITE_CANTOPEN] or
! 2142: ** [SQLITE_IOERR] rather than [SQLITE_NOMEM].
! 2143: **
! 2144: ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]
! 2145: ** must be either NULL or else pointers obtained from a prior
! 2146: ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have
! 2147: ** not yet been released.
! 2148: **
! 2149: ** The application must not read or write any part of
! 2150: ** a block of memory after it has been released using
! 2151: ** [sqlite3_free()] or [sqlite3_realloc()].
! 2152: */
! 2153: SQLITE_API void *sqlite3_malloc(int);
! 2154: SQLITE_API void *sqlite3_realloc(void*, int);
! 2155: SQLITE_API void sqlite3_free(void*);
! 2156:
! 2157: /*
! 2158: ** CAPI3REF: Memory Allocator Statistics
! 2159: **
! 2160: ** SQLite provides these two interfaces for reporting on the status
! 2161: ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]
! 2162: ** routines, which form the built-in memory allocation subsystem.
! 2163: **
! 2164: ** ^The [sqlite3_memory_used()] routine returns the number of bytes
! 2165: ** of memory currently outstanding (malloced but not freed).
! 2166: ** ^The [sqlite3_memory_highwater()] routine returns the maximum
! 2167: ** value of [sqlite3_memory_used()] since the high-water mark
! 2168: ** was last reset. ^The values returned by [sqlite3_memory_used()] and
! 2169: ** [sqlite3_memory_highwater()] include any overhead
! 2170: ** added by SQLite in its implementation of [sqlite3_malloc()],
! 2171: ** but not overhead added by the any underlying system library
! 2172: ** routines that [sqlite3_malloc()] may call.
! 2173: **
! 2174: ** ^The memory high-water mark is reset to the current value of
! 2175: ** [sqlite3_memory_used()] if and only if the parameter to
! 2176: ** [sqlite3_memory_highwater()] is true. ^The value returned
! 2177: ** by [sqlite3_memory_highwater(1)] is the high-water mark
! 2178: ** prior to the reset.
! 2179: */
! 2180: SQLITE_API sqlite3_int64 sqlite3_memory_used(void);
! 2181: SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag);
! 2182:
! 2183: /*
! 2184: ** CAPI3REF: Pseudo-Random Number Generator
! 2185: **
! 2186: ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to
! 2187: ** select random [ROWID | ROWIDs] when inserting new records into a table that
! 2188: ** already uses the largest possible [ROWID]. The PRNG is also used for
! 2189: ** the build-in random() and randomblob() SQL functions. This interface allows
! 2190: ** applications to access the same PRNG for other purposes.
! 2191: **
! 2192: ** ^A call to this routine stores N bytes of randomness into buffer P.
! 2193: **
! 2194: ** ^The first time this routine is invoked (either internally or by
! 2195: ** the application) the PRNG is seeded using randomness obtained
! 2196: ** from the xRandomness method of the default [sqlite3_vfs] object.
! 2197: ** ^On all subsequent invocations, the pseudo-randomness is generated
! 2198: ** internally and without recourse to the [sqlite3_vfs] xRandomness
! 2199: ** method.
! 2200: */
! 2201: SQLITE_API void sqlite3_randomness(int N, void *P);
! 2202:
! 2203: /*
! 2204: ** CAPI3REF: Compile-Time Authorization Callbacks
! 2205: **
! 2206: ** ^This routine registers an authorizer callback with a particular
! 2207: ** [database connection], supplied in the first argument.
! 2208: ** ^The authorizer callback is invoked as SQL statements are being compiled
! 2209: ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],
! 2210: ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various
! 2211: ** points during the compilation process, as logic is being created
! 2212: ** to perform various actions, the authorizer callback is invoked to
! 2213: ** see if those actions are allowed. ^The authorizer callback should
! 2214: ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the
! 2215: ** specific action but allow the SQL statement to continue to be
! 2216: ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be
! 2217: ** rejected with an error. ^If the authorizer callback returns
! 2218: ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]
! 2219: ** then the [sqlite3_prepare_v2()] or equivalent call that triggered
! 2220: ** the authorizer will fail with an error message.
! 2221: **
! 2222: ** When the callback returns [SQLITE_OK], that means the operation
! 2223: ** requested is ok. ^When the callback returns [SQLITE_DENY], the
! 2224: ** [sqlite3_prepare_v2()] or equivalent call that triggered the
! 2225: ** authorizer will fail with an error message explaining that
! 2226: ** access is denied.
! 2227: **
! 2228: ** ^The first parameter to the authorizer callback is a copy of the third
! 2229: ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter
! 2230: ** to the callback is an integer [SQLITE_COPY | action code] that specifies
! 2231: ** the particular action to be authorized. ^The third through sixth parameters
! 2232: ** to the callback are zero-terminated strings that contain additional
! 2233: ** details about the action to be authorized.
! 2234: **
! 2235: ** ^If the action code is [SQLITE_READ]
! 2236: ** and the callback returns [SQLITE_IGNORE] then the
! 2237: ** [prepared statement] statement is constructed to substitute
! 2238: ** a NULL value in place of the table column that would have
! 2239: ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]
! 2240: ** return can be used to deny an untrusted user access to individual
! 2241: ** columns of a table.
! 2242: ** ^If the action code is [SQLITE_DELETE] and the callback returns
! 2243: ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the
! 2244: ** [truncate optimization] is disabled and all rows are deleted individually.
! 2245: **
! 2246: ** An authorizer is used when [sqlite3_prepare | preparing]
! 2247: ** SQL statements from an untrusted source, to ensure that the SQL statements
! 2248: ** do not try to access data they are not allowed to see, or that they do not
! 2249: ** try to execute malicious statements that damage the database. For
! 2250: ** example, an application may allow a user to enter arbitrary
! 2251: ** SQL queries for evaluation by a database. But the application does
! 2252: ** not want the user to be able to make arbitrary changes to the
! 2253: ** database. An authorizer could then be put in place while the
! 2254: ** user-entered SQL is being [sqlite3_prepare | prepared] that
! 2255: ** disallows everything except [SELECT] statements.
! 2256: **
! 2257: ** Applications that need to process SQL from untrusted sources
! 2258: ** might also consider lowering resource limits using [sqlite3_limit()]
! 2259: ** and limiting database size using the [max_page_count] [PRAGMA]
! 2260: ** in addition to using an authorizer.
! 2261: **
! 2262: ** ^(Only a single authorizer can be in place on a database connection
! 2263: ** at a time. Each call to sqlite3_set_authorizer overrides the
! 2264: ** previous call.)^ ^Disable the authorizer by installing a NULL callback.
! 2265: ** The authorizer is disabled by default.
! 2266: **
! 2267: ** The authorizer callback must not do anything that will modify
! 2268: ** the database connection that invoked the authorizer callback.
! 2269: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
! 2270: ** database connections for the meaning of "modify" in this paragraph.
! 2271: **
! 2272: ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the
! 2273: ** statement might be re-prepared during [sqlite3_step()] due to a
! 2274: ** schema change. Hence, the application should ensure that the
! 2275: ** correct authorizer callback remains in place during the [sqlite3_step()].
! 2276: **
! 2277: ** ^Note that the authorizer callback is invoked only during
! 2278: ** [sqlite3_prepare()] or its variants. Authorization is not
! 2279: ** performed during statement evaluation in [sqlite3_step()], unless
! 2280: ** as stated in the previous paragraph, sqlite3_step() invokes
! 2281: ** sqlite3_prepare_v2() to reprepare a statement after a schema change.
! 2282: */
! 2283: SQLITE_API int sqlite3_set_authorizer(
! 2284: sqlite3*,
! 2285: int (*xAuth)(void*,int,const char*,const char*,const char*,const char*),
! 2286: void *pUserData
! 2287: );
! 2288:
! 2289: /*
! 2290: ** CAPI3REF: Authorizer Return Codes
! 2291: **
! 2292: ** The [sqlite3_set_authorizer | authorizer callback function] must
! 2293: ** return either [SQLITE_OK] or one of these two constants in order
! 2294: ** to signal SQLite whether or not the action is permitted. See the
! 2295: ** [sqlite3_set_authorizer | authorizer documentation] for additional
! 2296: ** information.
! 2297: **
! 2298: ** Note that SQLITE_IGNORE is also used as a [SQLITE_ROLLBACK | return code]
! 2299: ** from the [sqlite3_vtab_on_conflict()] interface.
! 2300: */
! 2301: #define SQLITE_DENY 1 /* Abort the SQL statement with an error */
! 2302: #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */
! 2303:
! 2304: /*
! 2305: ** CAPI3REF: Authorizer Action Codes
! 2306: **
! 2307: ** The [sqlite3_set_authorizer()] interface registers a callback function
! 2308: ** that is invoked to authorize certain SQL statement actions. The
! 2309: ** second parameter to the callback is an integer code that specifies
! 2310: ** what action is being authorized. These are the integer action codes that
! 2311: ** the authorizer callback may be passed.
! 2312: **
! 2313: ** These action code values signify what kind of operation is to be
! 2314: ** authorized. The 3rd and 4th parameters to the authorization
! 2315: ** callback function will be parameters or NULL depending on which of these
! 2316: ** codes is used as the second parameter. ^(The 5th parameter to the
! 2317: ** authorizer callback is the name of the database ("main", "temp",
! 2318: ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback
! 2319: ** is the name of the inner-most trigger or view that is responsible for
! 2320: ** the access attempt or NULL if this access attempt is directly from
! 2321: ** top-level SQL code.
! 2322: */
! 2323: /******************************************* 3rd ************ 4th ***********/
! 2324: #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */
! 2325: #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */
! 2326: #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */
! 2327: #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */
! 2328: #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */
! 2329: #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */
! 2330: #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */
! 2331: #define SQLITE_CREATE_VIEW 8 /* View Name NULL */
! 2332: #define SQLITE_DELETE 9 /* Table Name NULL */
! 2333: #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */
! 2334: #define SQLITE_DROP_TABLE 11 /* Table Name NULL */
! 2335: #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */
! 2336: #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */
! 2337: #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */
! 2338: #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */
! 2339: #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */
! 2340: #define SQLITE_DROP_VIEW 17 /* View Name NULL */
! 2341: #define SQLITE_INSERT 18 /* Table Name NULL */
! 2342: #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */
! 2343: #define SQLITE_READ 20 /* Table Name Column Name */
! 2344: #define SQLITE_SELECT 21 /* NULL NULL */
! 2345: #define SQLITE_TRANSACTION 22 /* Operation NULL */
! 2346: #define SQLITE_UPDATE 23 /* Table Name Column Name */
! 2347: #define SQLITE_ATTACH 24 /* Filename NULL */
! 2348: #define SQLITE_DETACH 25 /* Database Name NULL */
! 2349: #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */
! 2350: #define SQLITE_REINDEX 27 /* Index Name NULL */
! 2351: #define SQLITE_ANALYZE 28 /* Table Name NULL */
! 2352: #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */
! 2353: #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */
! 2354: #define SQLITE_FUNCTION 31 /* NULL Function Name */
! 2355: #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */
! 2356: #define SQLITE_COPY 0 /* No longer used */
! 2357:
! 2358: /*
! 2359: ** CAPI3REF: Tracing And Profiling Functions
! 2360: **
! 2361: ** These routines register callback functions that can be used for
! 2362: ** tracing and profiling the execution of SQL statements.
! 2363: **
! 2364: ** ^The callback function registered by sqlite3_trace() is invoked at
! 2365: ** various times when an SQL statement is being run by [sqlite3_step()].
! 2366: ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the
! 2367: ** SQL statement text as the statement first begins executing.
! 2368: ** ^(Additional sqlite3_trace() callbacks might occur
! 2369: ** as each triggered subprogram is entered. The callbacks for triggers
! 2370: ** contain a UTF-8 SQL comment that identifies the trigger.)^
! 2371: **
! 2372: ** ^The callback function registered by sqlite3_profile() is invoked
! 2373: ** as each SQL statement finishes. ^The profile callback contains
! 2374: ** the original statement text and an estimate of wall-clock time
! 2375: ** of how long that statement took to run. ^The profile callback
! 2376: ** time is in units of nanoseconds, however the current implementation
! 2377: ** is only capable of millisecond resolution so the six least significant
! 2378: ** digits in the time are meaningless. Future versions of SQLite
! 2379: ** might provide greater resolution on the profiler callback. The
! 2380: ** sqlite3_profile() function is considered experimental and is
! 2381: ** subject to change in future versions of SQLite.
! 2382: */
! 2383: SQLITE_API void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*);
! 2384: SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
! 2385: void(*xProfile)(void*,const char*,sqlite3_uint64), void*);
! 2386:
! 2387: /*
! 2388: ** CAPI3REF: Query Progress Callbacks
! 2389: **
! 2390: ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback
! 2391: ** function X to be invoked periodically during long running calls to
! 2392: ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for
! 2393: ** database connection D. An example use for this
! 2394: ** interface is to keep a GUI updated during a large query.
! 2395: **
! 2396: ** ^The parameter P is passed through as the only parameter to the
! 2397: ** callback function X. ^The parameter N is the number of
! 2398: ** [virtual machine instructions] that are evaluated between successive
! 2399: ** invocations of the callback X.
! 2400: **
! 2401: ** ^Only a single progress handler may be defined at one time per
! 2402: ** [database connection]; setting a new progress handler cancels the
! 2403: ** old one. ^Setting parameter X to NULL disables the progress handler.
! 2404: ** ^The progress handler is also disabled by setting N to a value less
! 2405: ** than 1.
! 2406: **
! 2407: ** ^If the progress callback returns non-zero, the operation is
! 2408: ** interrupted. This feature can be used to implement a
! 2409: ** "Cancel" button on a GUI progress dialog box.
! 2410: **
! 2411: ** The progress handler callback must not do anything that will modify
! 2412: ** the database connection that invoked the progress handler.
! 2413: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
! 2414: ** database connections for the meaning of "modify" in this paragraph.
! 2415: **
! 2416: */
! 2417: SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
! 2418:
! 2419: /*
! 2420: ** CAPI3REF: Opening A New Database Connection
! 2421: **
! 2422: ** ^These routines open an SQLite database file as specified by the
! 2423: ** filename argument. ^The filename argument is interpreted as UTF-8 for
! 2424: ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte
! 2425: ** order for sqlite3_open16(). ^(A [database connection] handle is usually
! 2426: ** returned in *ppDb, even if an error occurs. The only exception is that
! 2427: ** if SQLite is unable to allocate memory to hold the [sqlite3] object,
! 2428: ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]
! 2429: ** object.)^ ^(If the database is opened (and/or created) successfully, then
! 2430: ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The
! 2431: ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain
! 2432: ** an English language description of the error following a failure of any
! 2433: ** of the sqlite3_open() routines.
! 2434: **
! 2435: ** ^The default encoding for the database will be UTF-8 if
! 2436: ** sqlite3_open() or sqlite3_open_v2() is called and
! 2437: ** UTF-16 in the native byte order if sqlite3_open16() is used.
! 2438: **
! 2439: ** Whether or not an error occurs when it is opened, resources
! 2440: ** associated with the [database connection] handle should be released by
! 2441: ** passing it to [sqlite3_close()] when it is no longer required.
! 2442: **
! 2443: ** The sqlite3_open_v2() interface works like sqlite3_open()
! 2444: ** except that it accepts two additional parameters for additional control
! 2445: ** over the new database connection. ^(The flags parameter to
! 2446: ** sqlite3_open_v2() can take one of
! 2447: ** the following three values, optionally combined with the
! 2448: ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],
! 2449: ** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^
! 2450: **
! 2451: ** <dl>
! 2452: ** ^(<dt>[SQLITE_OPEN_READONLY]</dt>
! 2453: ** <dd>The database is opened in read-only mode. If the database does not
! 2454: ** already exist, an error is returned.</dd>)^
! 2455: **
! 2456: ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>
! 2457: ** <dd>The database is opened for reading and writing if possible, or reading
! 2458: ** only if the file is write protected by the operating system. In either
! 2459: ** case the database must already exist, otherwise an error is returned.</dd>)^
! 2460: **
! 2461: ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>
! 2462: ** <dd>The database is opened for reading and writing, and is created if
! 2463: ** it does not already exist. This is the behavior that is always used for
! 2464: ** sqlite3_open() and sqlite3_open16().</dd>)^
! 2465: ** </dl>
! 2466: **
! 2467: ** If the 3rd parameter to sqlite3_open_v2() is not one of the
! 2468: ** combinations shown above optionally combined with other
! 2469: ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]
! 2470: ** then the behavior is undefined.
! 2471: **
! 2472: ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection
! 2473: ** opens in the multi-thread [threading mode] as long as the single-thread
! 2474: ** mode has not been set at compile-time or start-time. ^If the
! 2475: ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens
! 2476: ** in the serialized [threading mode] unless single-thread was
! 2477: ** previously selected at compile-time or start-time.
! 2478: ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be
! 2479: ** eligible to use [shared cache mode], regardless of whether or not shared
! 2480: ** cache is enabled using [sqlite3_enable_shared_cache()]. ^The
! 2481: ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not
! 2482: ** participate in [shared cache mode] even if it is enabled.
! 2483: **
! 2484: ** ^The fourth parameter to sqlite3_open_v2() is the name of the
! 2485: ** [sqlite3_vfs] object that defines the operating system interface that
! 2486: ** the new database connection should use. ^If the fourth parameter is
! 2487: ** a NULL pointer then the default [sqlite3_vfs] object is used.
! 2488: **
! 2489: ** ^If the filename is ":memory:", then a private, temporary in-memory database
! 2490: ** is created for the connection. ^This in-memory database will vanish when
! 2491: ** the database connection is closed. Future versions of SQLite might
! 2492: ** make use of additional special filenames that begin with the ":" character.
! 2493: ** It is recommended that when a database filename actually does begin with
! 2494: ** a ":" character you should prefix the filename with a pathname such as
! 2495: ** "./" to avoid ambiguity.
! 2496: **
! 2497: ** ^If the filename is an empty string, then a private, temporary
! 2498: ** on-disk database will be created. ^This private database will be
! 2499: ** automatically deleted as soon as the database connection is closed.
! 2500: **
! 2501: ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>
! 2502: **
! 2503: ** ^If [URI filename] interpretation is enabled, and the filename argument
! 2504: ** begins with "file:", then the filename is interpreted as a URI. ^URI
! 2505: ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is
! 2506: ** set in the fourth argument to sqlite3_open_v2(), or if it has
! 2507: ** been enabled globally using the [SQLITE_CONFIG_URI] option with the
! 2508: ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.
! 2509: ** As of SQLite version 3.7.7, URI filename interpretation is turned off
! 2510: ** by default, but future releases of SQLite might enable URI filename
! 2511: ** interpretation by default. See "[URI filenames]" for additional
! 2512: ** information.
! 2513: **
! 2514: ** URI filenames are parsed according to RFC 3986. ^If the URI contains an
! 2515: ** authority, then it must be either an empty string or the string
! 2516: ** "localhost". ^If the authority is not an empty string or "localhost", an
! 2517: ** error is returned to the caller. ^The fragment component of a URI, if
! 2518: ** present, is ignored.
! 2519: **
! 2520: ** ^SQLite uses the path component of the URI as the name of the disk file
! 2521: ** which contains the database. ^If the path begins with a '/' character,
! 2522: ** then it is interpreted as an absolute path. ^If the path does not begin
! 2523: ** with a '/' (meaning that the authority section is omitted from the URI)
! 2524: ** then the path is interpreted as a relative path.
! 2525: ** ^On windows, the first component of an absolute path
! 2526: ** is a drive specification (e.g. "C:").
! 2527: **
! 2528: ** [[core URI query parameters]]
! 2529: ** The query component of a URI may contain parameters that are interpreted
! 2530: ** either by SQLite itself, or by a [VFS | custom VFS implementation].
! 2531: ** SQLite interprets the following three query parameters:
! 2532: **
! 2533: ** <ul>
! 2534: ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of
! 2535: ** a VFS object that provides the operating system interface that should
! 2536: ** be used to access the database file on disk. ^If this option is set to
! 2537: ** an empty string the default VFS object is used. ^Specifying an unknown
! 2538: ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is
! 2539: ** present, then the VFS specified by the option takes precedence over
! 2540: ** the value passed as the fourth parameter to sqlite3_open_v2().
! 2541: **
! 2542: ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw" or
! 2543: ** "rwc". Attempting to set it to any other value is an error)^.
! 2544: ** ^If "ro" is specified, then the database is opened for read-only
! 2545: ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the
! 2546: ** third argument to sqlite3_prepare_v2(). ^If the mode option is set to
! 2547: ** "rw", then the database is opened for read-write (but not create)
! 2548: ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had
! 2549: ** been set. ^Value "rwc" is equivalent to setting both
! 2550: ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If sqlite3_open_v2() is
! 2551: ** used, it is an error to specify a value for the mode parameter that is
! 2552: ** less restrictive than that specified by the flags passed as the third
! 2553: ** parameter.
! 2554: **
! 2555: ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or
! 2556: ** "private". ^Setting it to "shared" is equivalent to setting the
! 2557: ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to
! 2558: ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is
! 2559: ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
! 2560: ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in
! 2561: ** a URI filename, its value overrides any behaviour requested by setting
! 2562: ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
! 2563: ** </ul>
! 2564: **
! 2565: ** ^Specifying an unknown parameter in the query component of a URI is not an
! 2566: ** error. Future versions of SQLite might understand additional query
! 2567: ** parameters. See "[query parameters with special meaning to SQLite]" for
! 2568: ** additional information.
! 2569: **
! 2570: ** [[URI filename examples]] <h3>URI filename examples</h3>
! 2571: **
! 2572: ** <table border="1" align=center cellpadding=5>
! 2573: ** <tr><th> URI filenames <th> Results
! 2574: ** <tr><td> file:data.db <td>
! 2575: ** Open the file "data.db" in the current directory.
! 2576: ** <tr><td> file:/home/fred/data.db<br>
! 2577: ** file:///home/fred/data.db <br>
! 2578: ** file://localhost/home/fred/data.db <br> <td>
! 2579: ** Open the database file "/home/fred/data.db".
! 2580: ** <tr><td> file://darkstar/home/fred/data.db <td>
! 2581: ** An error. "darkstar" is not a recognized authority.
! 2582: ** <tr><td style="white-space:nowrap">
! 2583: ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db
! 2584: ** <td> Windows only: Open the file "data.db" on fred's desktop on drive
! 2585: ** C:. Note that the %20 escaping in this example is not strictly
! 2586: ** necessary - space characters can be used literally
! 2587: ** in URI filenames.
! 2588: ** <tr><td> file:data.db?mode=ro&cache=private <td>
! 2589: ** Open file "data.db" in the current directory for read-only access.
! 2590: ** Regardless of whether or not shared-cache mode is enabled by
! 2591: ** default, use a private cache.
! 2592: ** <tr><td> file:/home/fred/data.db?vfs=unix-nolock <td>
! 2593: ** Open file "/home/fred/data.db". Use the special VFS "unix-nolock".
! 2594: ** <tr><td> file:data.db?mode=readonly <td>
! 2595: ** An error. "readonly" is not a valid option for the "mode" parameter.
! 2596: ** </table>
! 2597: **
! 2598: ** ^URI hexadecimal escape sequences (%HH) are supported within the path and
! 2599: ** query components of a URI. A hexadecimal escape sequence consists of a
! 2600: ** percent sign - "%" - followed by exactly two hexadecimal digits
! 2601: ** specifying an octet value. ^Before the path or query components of a
! 2602: ** URI filename are interpreted, they are encoded using UTF-8 and all
! 2603: ** hexadecimal escape sequences replaced by a single byte containing the
! 2604: ** corresponding octet. If this process generates an invalid UTF-8 encoding,
! 2605: ** the results are undefined.
! 2606: **
! 2607: ** <b>Note to Windows users:</b> The encoding used for the filename argument
! 2608: ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever
! 2609: ** codepage is currently defined. Filenames containing international
! 2610: ** characters must be converted to UTF-8 prior to passing them into
! 2611: ** sqlite3_open() or sqlite3_open_v2().
! 2612: */
! 2613: SQLITE_API int sqlite3_open(
! 2614: const char *filename, /* Database filename (UTF-8) */
! 2615: sqlite3 **ppDb /* OUT: SQLite db handle */
! 2616: );
! 2617: SQLITE_API int sqlite3_open16(
! 2618: const void *filename, /* Database filename (UTF-16) */
! 2619: sqlite3 **ppDb /* OUT: SQLite db handle */
! 2620: );
! 2621: SQLITE_API int sqlite3_open_v2(
! 2622: const char *filename, /* Database filename (UTF-8) */
! 2623: sqlite3 **ppDb, /* OUT: SQLite db handle */
! 2624: int flags, /* Flags */
! 2625: const char *zVfs /* Name of VFS module to use */
! 2626: );
! 2627:
! 2628: /*
! 2629: ** CAPI3REF: Obtain Values For URI Parameters
! 2630: **
! 2631: ** These are utility routines, useful to VFS implementations, that check
! 2632: ** to see if a database file was a URI that contained a specific query
! 2633: ** parameter, and if so obtains the value of that query parameter.
! 2634: **
! 2635: ** If F is the database filename pointer passed into the xOpen() method of
! 2636: ** a VFS implementation when the flags parameter to xOpen() has one or
! 2637: ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and
! 2638: ** P is the name of the query parameter, then
! 2639: ** sqlite3_uri_parameter(F,P) returns the value of the P
! 2640: ** parameter if it exists or a NULL pointer if P does not appear as a
! 2641: ** query parameter on F. If P is a query parameter of F
! 2642: ** has no explicit value, then sqlite3_uri_parameter(F,P) returns
! 2643: ** a pointer to an empty string.
! 2644: **
! 2645: ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean
! 2646: ** parameter and returns true (1) or false (0) according to the value
! 2647: ** of P. The value of P is true if it is "yes" or "true" or "on" or
! 2648: ** a non-zero number and is false otherwise. If P is not a query parameter
! 2649: ** on F then sqlite3_uri_boolean(F,P,B) returns (B!=0).
! 2650: **
! 2651: ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a
! 2652: ** 64-bit signed integer and returns that integer, or D if P does not
! 2653: ** exist. If the value of P is something other than an integer, then
! 2654: ** zero is returned.
! 2655: **
! 2656: ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and
! 2657: ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and
! 2658: ** is not a database file pathname pointer that SQLite passed into the xOpen
! 2659: ** VFS method, then the behavior of this routine is undefined and probably
! 2660: ** undesirable.
! 2661: */
! 2662: SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam);
! 2663: SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault);
! 2664: SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64);
! 2665:
! 2666:
! 2667: /*
! 2668: ** CAPI3REF: Error Codes And Messages
! 2669: **
! 2670: ** ^The sqlite3_errcode() interface returns the numeric [result code] or
! 2671: ** [extended result code] for the most recent failed sqlite3_* API call
! 2672: ** associated with a [database connection]. If a prior API call failed
! 2673: ** but the most recent API call succeeded, the return value from
! 2674: ** sqlite3_errcode() is undefined. ^The sqlite3_extended_errcode()
! 2675: ** interface is the same except that it always returns the
! 2676: ** [extended result code] even when extended result codes are
! 2677: ** disabled.
! 2678: **
! 2679: ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language
! 2680: ** text that describes the error, as either UTF-8 or UTF-16 respectively.
! 2681: ** ^(Memory to hold the error message string is managed internally.
! 2682: ** The application does not need to worry about freeing the result.
! 2683: ** However, the error string might be overwritten or deallocated by
! 2684: ** subsequent calls to other SQLite interface functions.)^
! 2685: **
! 2686: ** When the serialized [threading mode] is in use, it might be the
! 2687: ** case that a second error occurs on a separate thread in between
! 2688: ** the time of the first error and the call to these interfaces.
! 2689: ** When that happens, the second error will be reported since these
! 2690: ** interfaces always report the most recent result. To avoid
! 2691: ** this, each thread can obtain exclusive use of the [database connection] D
! 2692: ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning
! 2693: ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after
! 2694: ** all calls to the interfaces listed here are completed.
! 2695: **
! 2696: ** If an interface fails with SQLITE_MISUSE, that means the interface
! 2697: ** was invoked incorrectly by the application. In that case, the
! 2698: ** error code and message may or may not be set.
! 2699: */
! 2700: SQLITE_API int sqlite3_errcode(sqlite3 *db);
! 2701: SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
! 2702: SQLITE_API const char *sqlite3_errmsg(sqlite3*);
! 2703: SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
! 2704:
! 2705: /*
! 2706: ** CAPI3REF: SQL Statement Object
! 2707: ** KEYWORDS: {prepared statement} {prepared statements}
! 2708: **
! 2709: ** An instance of this object represents a single SQL statement.
! 2710: ** This object is variously known as a "prepared statement" or a
! 2711: ** "compiled SQL statement" or simply as a "statement".
! 2712: **
! 2713: ** The life of a statement object goes something like this:
! 2714: **
! 2715: ** <ol>
! 2716: ** <li> Create the object using [sqlite3_prepare_v2()] or a related
! 2717: ** function.
! 2718: ** <li> Bind values to [host parameters] using the sqlite3_bind_*()
! 2719: ** interfaces.
! 2720: ** <li> Run the SQL by calling [sqlite3_step()] one or more times.
! 2721: ** <li> Reset the statement using [sqlite3_reset()] then go back
! 2722: ** to step 2. Do this zero or more times.
! 2723: ** <li> Destroy the object using [sqlite3_finalize()].
! 2724: ** </ol>
! 2725: **
! 2726: ** Refer to documentation on individual methods above for additional
! 2727: ** information.
! 2728: */
! 2729: typedef struct sqlite3_stmt sqlite3_stmt;
! 2730:
! 2731: /*
! 2732: ** CAPI3REF: Run-time Limits
! 2733: **
! 2734: ** ^(This interface allows the size of various constructs to be limited
! 2735: ** on a connection by connection basis. The first parameter is the
! 2736: ** [database connection] whose limit is to be set or queried. The
! 2737: ** second parameter is one of the [limit categories] that define a
! 2738: ** class of constructs to be size limited. The third parameter is the
! 2739: ** new limit for that construct.)^
! 2740: **
! 2741: ** ^If the new limit is a negative number, the limit is unchanged.
! 2742: ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a
! 2743: ** [limits | hard upper bound]
! 2744: ** set at compile-time by a C preprocessor macro called
! 2745: ** [limits | SQLITE_MAX_<i>NAME</i>].
! 2746: ** (The "_LIMIT_" in the name is changed to "_MAX_".))^
! 2747: ** ^Attempts to increase a limit above its hard upper bound are
! 2748: ** silently truncated to the hard upper bound.
! 2749: **
! 2750: ** ^Regardless of whether or not the limit was changed, the
! 2751: ** [sqlite3_limit()] interface returns the prior value of the limit.
! 2752: ** ^Hence, to find the current value of a limit without changing it,
! 2753: ** simply invoke this interface with the third parameter set to -1.
! 2754: **
! 2755: ** Run-time limits are intended for use in applications that manage
! 2756: ** both their own internal database and also databases that are controlled
! 2757: ** by untrusted external sources. An example application might be a
! 2758: ** web browser that has its own databases for storing history and
! 2759: ** separate databases controlled by JavaScript applications downloaded
! 2760: ** off the Internet. The internal databases can be given the
! 2761: ** large, default limits. Databases managed by external sources can
! 2762: ** be given much smaller limits designed to prevent a denial of service
! 2763: ** attack. Developers might also want to use the [sqlite3_set_authorizer()]
! 2764: ** interface to further control untrusted SQL. The size of the database
! 2765: ** created by an untrusted script can be contained using the
! 2766: ** [max_page_count] [PRAGMA].
! 2767: **
! 2768: ** New run-time limit categories may be added in future releases.
! 2769: */
! 2770: SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
! 2771:
! 2772: /*
! 2773: ** CAPI3REF: Run-Time Limit Categories
! 2774: ** KEYWORDS: {limit category} {*limit categories}
! 2775: **
! 2776: ** These constants define various performance limits
! 2777: ** that can be lowered at run-time using [sqlite3_limit()].
! 2778: ** The synopsis of the meanings of the various limits is shown below.
! 2779: ** Additional information is available at [limits | Limits in SQLite].
! 2780: **
! 2781: ** <dl>
! 2782: ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>
! 2783: ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^
! 2784: **
! 2785: ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>
! 2786: ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^
! 2787: **
! 2788: ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>
! 2789: ** <dd>The maximum number of columns in a table definition or in the
! 2790: ** result set of a [SELECT] or the maximum number of columns in an index
! 2791: ** or in an ORDER BY or GROUP BY clause.</dd>)^
! 2792: **
! 2793: ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>
! 2794: ** <dd>The maximum depth of the parse tree on any expression.</dd>)^
! 2795: **
! 2796: ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>
! 2797: ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^
! 2798: **
! 2799: ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>
! 2800: ** <dd>The maximum number of instructions in a virtual machine program
! 2801: ** used to implement an SQL statement. This limit is not currently
! 2802: ** enforced, though that might be added in some future release of
! 2803: ** SQLite.</dd>)^
! 2804: **
! 2805: ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>
! 2806: ** <dd>The maximum number of arguments on a function.</dd>)^
! 2807: **
! 2808: ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>
! 2809: ** <dd>The maximum number of [ATTACH | attached databases].)^</dd>
! 2810: **
! 2811: ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]
! 2812: ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>
! 2813: ** <dd>The maximum length of the pattern argument to the [LIKE] or
! 2814: ** [GLOB] operators.</dd>)^
! 2815: **
! 2816: ** [[SQLITE_LIMIT_VARIABLE_NUMBER]]
! 2817: ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>
! 2818: ** <dd>The maximum index number of any [parameter] in an SQL statement.)^
! 2819: **
! 2820: ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>
! 2821: ** <dd>The maximum depth of recursion for triggers.</dd>)^
! 2822: ** </dl>
! 2823: */
! 2824: #define SQLITE_LIMIT_LENGTH 0
! 2825: #define SQLITE_LIMIT_SQL_LENGTH 1
! 2826: #define SQLITE_LIMIT_COLUMN 2
! 2827: #define SQLITE_LIMIT_EXPR_DEPTH 3
! 2828: #define SQLITE_LIMIT_COMPOUND_SELECT 4
! 2829: #define SQLITE_LIMIT_VDBE_OP 5
! 2830: #define SQLITE_LIMIT_FUNCTION_ARG 6
! 2831: #define SQLITE_LIMIT_ATTACHED 7
! 2832: #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8
! 2833: #define SQLITE_LIMIT_VARIABLE_NUMBER 9
! 2834: #define SQLITE_LIMIT_TRIGGER_DEPTH 10
! 2835:
! 2836: /*
! 2837: ** CAPI3REF: Compiling An SQL Statement
! 2838: ** KEYWORDS: {SQL statement compiler}
! 2839: **
! 2840: ** To execute an SQL query, it must first be compiled into a byte-code
! 2841: ** program using one of these routines.
! 2842: **
! 2843: ** The first argument, "db", is a [database connection] obtained from a
! 2844: ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
! 2845: ** [sqlite3_open16()]. The database connection must not have been closed.
! 2846: **
! 2847: ** The second argument, "zSql", is the statement to be compiled, encoded
! 2848: ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()
! 2849: ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
! 2850: ** use UTF-16.
! 2851: **
! 2852: ** ^If the nByte argument is less than zero, then zSql is read up to the
! 2853: ** first zero terminator. ^If nByte is non-negative, then it is the maximum
! 2854: ** number of bytes read from zSql. ^When nByte is non-negative, the
! 2855: ** zSql string ends at either the first '\000' or '\u0000' character or
! 2856: ** the nByte-th byte, whichever comes first. If the caller knows
! 2857: ** that the supplied string is nul-terminated, then there is a small
! 2858: ** performance advantage to be gained by passing an nByte parameter that
! 2859: ** is equal to the number of bytes in the input string <i>including</i>
! 2860: ** the nul-terminator bytes as this saves SQLite from having to
! 2861: ** make a copy of the input string.
! 2862: **
! 2863: ** ^If pzTail is not NULL then *pzTail is made to point to the first byte
! 2864: ** past the end of the first SQL statement in zSql. These routines only
! 2865: ** compile the first statement in zSql, so *pzTail is left pointing to
! 2866: ** what remains uncompiled.
! 2867: **
! 2868: ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be
! 2869: ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set
! 2870: ** to NULL. ^If the input text contains no SQL (if the input is an empty
! 2871: ** string or a comment) then *ppStmt is set to NULL.
! 2872: ** The calling procedure is responsible for deleting the compiled
! 2873: ** SQL statement using [sqlite3_finalize()] after it has finished with it.
! 2874: ** ppStmt may not be NULL.
! 2875: **
! 2876: ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];
! 2877: ** otherwise an [error code] is returned.
! 2878: **
! 2879: ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
! 2880: ** recommended for all new programs. The two older interfaces are retained
! 2881: ** for backwards compatibility, but their use is discouraged.
! 2882: ** ^In the "v2" interfaces, the prepared statement
! 2883: ** that is returned (the [sqlite3_stmt] object) contains a copy of the
! 2884: ** original SQL text. This causes the [sqlite3_step()] interface to
! 2885: ** behave differently in three ways:
! 2886: **
! 2887: ** <ol>
! 2888: ** <li>
! 2889: ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
! 2890: ** always used to do, [sqlite3_step()] will automatically recompile the SQL
! 2891: ** statement and try to run it again.
! 2892: ** </li>
! 2893: **
! 2894: ** <li>
! 2895: ** ^When an error occurs, [sqlite3_step()] will return one of the detailed
! 2896: ** [error codes] or [extended error codes]. ^The legacy behavior was that
! 2897: ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code
! 2898: ** and the application would have to make a second call to [sqlite3_reset()]
! 2899: ** in order to find the underlying cause of the problem. With the "v2" prepare
! 2900: ** interfaces, the underlying reason for the error is returned immediately.
! 2901: ** </li>
! 2902: **
! 2903: ** <li>
! 2904: ** ^If the specific value bound to [parameter | host parameter] in the
! 2905: ** WHERE clause might influence the choice of query plan for a statement,
! 2906: ** then the statement will be automatically recompiled, as if there had been
! 2907: ** a schema change, on the first [sqlite3_step()] call following any change
! 2908: ** to the [sqlite3_bind_text | bindings] of that [parameter].
! 2909: ** ^The specific value of WHERE-clause [parameter] might influence the
! 2910: ** choice of query plan if the parameter is the left-hand side of a [LIKE]
! 2911: ** or [GLOB] operator or if the parameter is compared to an indexed column
! 2912: ** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.
! 2913: ** the
! 2914: ** </li>
! 2915: ** </ol>
! 2916: */
! 2917: SQLITE_API int sqlite3_prepare(
! 2918: sqlite3 *db, /* Database handle */
! 2919: const char *zSql, /* SQL statement, UTF-8 encoded */
! 2920: int nByte, /* Maximum length of zSql in bytes. */
! 2921: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
! 2922: const char **pzTail /* OUT: Pointer to unused portion of zSql */
! 2923: );
! 2924: SQLITE_API int sqlite3_prepare_v2(
! 2925: sqlite3 *db, /* Database handle */
! 2926: const char *zSql, /* SQL statement, UTF-8 encoded */
! 2927: int nByte, /* Maximum length of zSql in bytes. */
! 2928: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
! 2929: const char **pzTail /* OUT: Pointer to unused portion of zSql */
! 2930: );
! 2931: SQLITE_API int sqlite3_prepare16(
! 2932: sqlite3 *db, /* Database handle */
! 2933: const void *zSql, /* SQL statement, UTF-16 encoded */
! 2934: int nByte, /* Maximum length of zSql in bytes. */
! 2935: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
! 2936: const void **pzTail /* OUT: Pointer to unused portion of zSql */
! 2937: );
! 2938: SQLITE_API int sqlite3_prepare16_v2(
! 2939: sqlite3 *db, /* Database handle */
! 2940: const void *zSql, /* SQL statement, UTF-16 encoded */
! 2941: int nByte, /* Maximum length of zSql in bytes. */
! 2942: sqlite3_stmt **ppStmt, /* OUT: Statement handle */
! 2943: const void **pzTail /* OUT: Pointer to unused portion of zSql */
! 2944: );
! 2945:
! 2946: /*
! 2947: ** CAPI3REF: Retrieving Statement SQL
! 2948: **
! 2949: ** ^This interface can be used to retrieve a saved copy of the original
! 2950: ** SQL text used to create a [prepared statement] if that statement was
! 2951: ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
! 2952: */
! 2953: SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt);
! 2954:
! 2955: /*
! 2956: ** CAPI3REF: Determine If An SQL Statement Writes The Database
! 2957: **
! 2958: ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if
! 2959: ** and only if the [prepared statement] X makes no direct changes to
! 2960: ** the content of the database file.
! 2961: **
! 2962: ** Note that [application-defined SQL functions] or
! 2963: ** [virtual tables] might change the database indirectly as a side effect.
! 2964: ** ^(For example, if an application defines a function "eval()" that
! 2965: ** calls [sqlite3_exec()], then the following SQL statement would
! 2966: ** change the database file through side-effects:
! 2967: **
! 2968: ** <blockquote><pre>
! 2969: ** SELECT eval('DELETE FROM t1') FROM t2;
! 2970: ** </pre></blockquote>
! 2971: **
! 2972: ** But because the [SELECT] statement does not change the database file
! 2973: ** directly, sqlite3_stmt_readonly() would still return true.)^
! 2974: **
! 2975: ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],
! 2976: ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,
! 2977: ** since the statements themselves do not actually modify the database but
! 2978: ** rather they control the timing of when other statements modify the
! 2979: ** database. ^The [ATTACH] and [DETACH] statements also cause
! 2980: ** sqlite3_stmt_readonly() to return true since, while those statements
! 2981: ** change the configuration of a database connection, they do not make
! 2982: ** changes to the content of the database files on disk.
! 2983: */
! 2984: SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt);
! 2985:
! 2986: /*
! 2987: ** CAPI3REF: Determine If A Prepared Statement Has Been Reset
! 2988: **
! 2989: ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the
! 2990: ** [prepared statement] S has been stepped at least once using
! 2991: ** [sqlite3_step(S)] but has not run to completion and/or has not
! 2992: ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)
! 2993: ** interface returns false if S is a NULL pointer. If S is not a
! 2994: ** NULL pointer and is not a pointer to a valid [prepared statement]
! 2995: ** object, then the behavior is undefined and probably undesirable.
! 2996: **
! 2997: ** This interface can be used in combination [sqlite3_next_stmt()]
! 2998: ** to locate all prepared statements associated with a database
! 2999: ** connection that are in need of being reset. This can be used,
! 3000: ** for example, in diagnostic routines to search for prepared
! 3001: ** statements that are holding a transaction open.
! 3002: */
! 3003: SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*);
! 3004:
! 3005: /*
! 3006: ** CAPI3REF: Dynamically Typed Value Object
! 3007: ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}
! 3008: **
! 3009: ** SQLite uses the sqlite3_value object to represent all values
! 3010: ** that can be stored in a database table. SQLite uses dynamic typing
! 3011: ** for the values it stores. ^Values stored in sqlite3_value objects
! 3012: ** can be integers, floating point values, strings, BLOBs, or NULL.
! 3013: **
! 3014: ** An sqlite3_value object may be either "protected" or "unprotected".
! 3015: ** Some interfaces require a protected sqlite3_value. Other interfaces
! 3016: ** will accept either a protected or an unprotected sqlite3_value.
! 3017: ** Every interface that accepts sqlite3_value arguments specifies
! 3018: ** whether or not it requires a protected sqlite3_value.
! 3019: **
! 3020: ** The terms "protected" and "unprotected" refer to whether or not
! 3021: ** a mutex is held. An internal mutex is held for a protected
! 3022: ** sqlite3_value object but no mutex is held for an unprotected
! 3023: ** sqlite3_value object. If SQLite is compiled to be single-threaded
! 3024: ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)
! 3025: ** or if SQLite is run in one of reduced mutex modes
! 3026: ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]
! 3027: ** then there is no distinction between protected and unprotected
! 3028: ** sqlite3_value objects and they can be used interchangeably. However,
! 3029: ** for maximum code portability it is recommended that applications
! 3030: ** still make the distinction between protected and unprotected
! 3031: ** sqlite3_value objects even when not strictly required.
! 3032: **
! 3033: ** ^The sqlite3_value objects that are passed as parameters into the
! 3034: ** implementation of [application-defined SQL functions] are protected.
! 3035: ** ^The sqlite3_value object returned by
! 3036: ** [sqlite3_column_value()] is unprotected.
! 3037: ** Unprotected sqlite3_value objects may only be used with
! 3038: ** [sqlite3_result_value()] and [sqlite3_bind_value()].
! 3039: ** The [sqlite3_value_blob | sqlite3_value_type()] family of
! 3040: ** interfaces require protected sqlite3_value objects.
! 3041: */
! 3042: typedef struct Mem sqlite3_value;
! 3043:
! 3044: /*
! 3045: ** CAPI3REF: SQL Function Context Object
! 3046: **
! 3047: ** The context in which an SQL function executes is stored in an
! 3048: ** sqlite3_context object. ^A pointer to an sqlite3_context object
! 3049: ** is always first parameter to [application-defined SQL functions].
! 3050: ** The application-defined SQL function implementation will pass this
! 3051: ** pointer through into calls to [sqlite3_result_int | sqlite3_result()],
! 3052: ** [sqlite3_aggregate_context()], [sqlite3_user_data()],
! 3053: ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],
! 3054: ** and/or [sqlite3_set_auxdata()].
! 3055: */
! 3056: typedef struct sqlite3_context sqlite3_context;
! 3057:
! 3058: /*
! 3059: ** CAPI3REF: Binding Values To Prepared Statements
! 3060: ** KEYWORDS: {host parameter} {host parameters} {host parameter name}
! 3061: ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}
! 3062: **
! 3063: ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,
! 3064: ** literals may be replaced by a [parameter] that matches one of following
! 3065: ** templates:
! 3066: **
! 3067: ** <ul>
! 3068: ** <li> ?
! 3069: ** <li> ?NNN
! 3070: ** <li> :VVV
! 3071: ** <li> @VVV
! 3072: ** <li> $VVV
! 3073: ** </ul>
! 3074: **
! 3075: ** In the templates above, NNN represents an integer literal,
! 3076: ** and VVV represents an alphanumeric identifier.)^ ^The values of these
! 3077: ** parameters (also called "host parameter names" or "SQL parameters")
! 3078: ** can be set using the sqlite3_bind_*() routines defined here.
! 3079: **
! 3080: ** ^The first argument to the sqlite3_bind_*() routines is always
! 3081: ** a pointer to the [sqlite3_stmt] object returned from
! 3082: ** [sqlite3_prepare_v2()] or its variants.
! 3083: **
! 3084: ** ^The second argument is the index of the SQL parameter to be set.
! 3085: ** ^The leftmost SQL parameter has an index of 1. ^When the same named
! 3086: ** SQL parameter is used more than once, second and subsequent
! 3087: ** occurrences have the same index as the first occurrence.
! 3088: ** ^The index for named parameters can be looked up using the
! 3089: ** [sqlite3_bind_parameter_index()] API if desired. ^The index
! 3090: ** for "?NNN" parameters is the value of NNN.
! 3091: ** ^The NNN value must be between 1 and the [sqlite3_limit()]
! 3092: ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
! 3093: **
! 3094: ** ^The third argument is the value to bind to the parameter.
! 3095: **
! 3096: ** ^(In those routines that have a fourth argument, its value is the
! 3097: ** number of bytes in the parameter. To be clear: the value is the
! 3098: ** number of <u>bytes</u> in the value, not the number of characters.)^
! 3099: ** ^If the fourth parameter is negative, the length of the string is
! 3100: ** the number of bytes up to the first zero terminator.
! 3101: ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
! 3102: ** or sqlite3_bind_text16() then that parameter must be the byte offset
! 3103: ** where the NUL terminator would occur assuming the string were NUL
! 3104: ** terminated. If any NUL characters occur at byte offsets less than
! 3105: ** the value of the fourth parameter then the resulting string value will
! 3106: ** contain embedded NULs. The result of expressions involving strings
! 3107: ** with embedded NULs is undefined.
! 3108: **
! 3109: ** ^The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and
! 3110: ** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or
! 3111: ** string after SQLite has finished with it. ^The destructor is called
! 3112: ** to dispose of the BLOB or string even if the call to sqlite3_bind_blob(),
! 3113: ** sqlite3_bind_text(), or sqlite3_bind_text16() fails.
! 3114: ** ^If the fifth argument is
! 3115: ** the special value [SQLITE_STATIC], then SQLite assumes that the
! 3116: ** information is in static, unmanaged space and does not need to be freed.
! 3117: ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then
! 3118: ** SQLite makes its own private copy of the data immediately, before
! 3119: ** the sqlite3_bind_*() routine returns.
! 3120: **
! 3121: ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that
! 3122: ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory
! 3123: ** (just an integer to hold its size) while it is being processed.
! 3124: ** Zeroblobs are intended to serve as placeholders for BLOBs whose
! 3125: ** content is later written using
! 3126: ** [sqlite3_blob_open | incremental BLOB I/O] routines.
! 3127: ** ^A negative value for the zeroblob results in a zero-length BLOB.
! 3128: **
! 3129: ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer
! 3130: ** for the [prepared statement] or with a prepared statement for which
! 3131: ** [sqlite3_step()] has been called more recently than [sqlite3_reset()],
! 3132: ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()
! 3133: ** routine is passed a [prepared statement] that has been finalized, the
! 3134: ** result is undefined and probably harmful.
! 3135: **
! 3136: ** ^Bindings are not cleared by the [sqlite3_reset()] routine.
! 3137: ** ^Unbound parameters are interpreted as NULL.
! 3138: **
! 3139: ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an
! 3140: ** [error code] if anything goes wrong.
! 3141: ** ^[SQLITE_RANGE] is returned if the parameter
! 3142: ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.
! 3143: **
! 3144: ** See also: [sqlite3_bind_parameter_count()],
! 3145: ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].
! 3146: */
! 3147: SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*));
! 3148: SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double);
! 3149: SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int);
! 3150: SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64);
! 3151: SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int);
! 3152: SQLITE_API int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*));
! 3153: SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*));
! 3154: SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*);
! 3155: SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n);
! 3156:
! 3157: /*
! 3158: ** CAPI3REF: Number Of SQL Parameters
! 3159: **
! 3160: ** ^This routine can be used to find the number of [SQL parameters]
! 3161: ** in a [prepared statement]. SQL parameters are tokens of the
! 3162: ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as
! 3163: ** placeholders for values that are [sqlite3_bind_blob | bound]
! 3164: ** to the parameters at a later time.
! 3165: **
! 3166: ** ^(This routine actually returns the index of the largest (rightmost)
! 3167: ** parameter. For all forms except ?NNN, this will correspond to the
! 3168: ** number of unique parameters. If parameters of the ?NNN form are used,
! 3169: ** there may be gaps in the list.)^
! 3170: **
! 3171: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
! 3172: ** [sqlite3_bind_parameter_name()], and
! 3173: ** [sqlite3_bind_parameter_index()].
! 3174: */
! 3175: SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*);
! 3176:
! 3177: /*
! 3178: ** CAPI3REF: Name Of A Host Parameter
! 3179: **
! 3180: ** ^The sqlite3_bind_parameter_name(P,N) interface returns
! 3181: ** the name of the N-th [SQL parameter] in the [prepared statement] P.
! 3182: ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"
! 3183: ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"
! 3184: ** respectively.
! 3185: ** In other words, the initial ":" or "$" or "@" or "?"
! 3186: ** is included as part of the name.)^
! 3187: ** ^Parameters of the form "?" without a following integer have no name
! 3188: ** and are referred to as "nameless" or "anonymous parameters".
! 3189: **
! 3190: ** ^The first host parameter has an index of 1, not 0.
! 3191: **
! 3192: ** ^If the value N is out of range or if the N-th parameter is
! 3193: ** nameless, then NULL is returned. ^The returned string is
! 3194: ** always in UTF-8 encoding even if the named parameter was
! 3195: ** originally specified as UTF-16 in [sqlite3_prepare16()] or
! 3196: ** [sqlite3_prepare16_v2()].
! 3197: **
! 3198: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
! 3199: ** [sqlite3_bind_parameter_count()], and
! 3200: ** [sqlite3_bind_parameter_index()].
! 3201: */
! 3202: SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int);
! 3203:
! 3204: /*
! 3205: ** CAPI3REF: Index Of A Parameter With A Given Name
! 3206: **
! 3207: ** ^Return the index of an SQL parameter given its name. ^The
! 3208: ** index value returned is suitable for use as the second
! 3209: ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero
! 3210: ** is returned if no matching parameter is found. ^The parameter
! 3211: ** name must be given in UTF-8 even if the original statement
! 3212: ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].
! 3213: **
! 3214: ** See also: [sqlite3_bind_blob|sqlite3_bind()],
! 3215: ** [sqlite3_bind_parameter_count()], and
! 3216: ** [sqlite3_bind_parameter_index()].
! 3217: */
! 3218: SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName);
! 3219:
! 3220: /*
! 3221: ** CAPI3REF: Reset All Bindings On A Prepared Statement
! 3222: **
! 3223: ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset
! 3224: ** the [sqlite3_bind_blob | bindings] on a [prepared statement].
! 3225: ** ^Use this routine to reset all host parameters to NULL.
! 3226: */
! 3227: SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*);
! 3228:
! 3229: /*
! 3230: ** CAPI3REF: Number Of Columns In A Result Set
! 3231: **
! 3232: ** ^Return the number of columns in the result set returned by the
! 3233: ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL
! 3234: ** statement that does not return data (for example an [UPDATE]).
! 3235: **
! 3236: ** See also: [sqlite3_data_count()]
! 3237: */
! 3238: SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt);
! 3239:
! 3240: /*
! 3241: ** CAPI3REF: Column Names In A Result Set
! 3242: **
! 3243: ** ^These routines return the name assigned to a particular column
! 3244: ** in the result set of a [SELECT] statement. ^The sqlite3_column_name()
! 3245: ** interface returns a pointer to a zero-terminated UTF-8 string
! 3246: ** and sqlite3_column_name16() returns a pointer to a zero-terminated
! 3247: ** UTF-16 string. ^The first parameter is the [prepared statement]
! 3248: ** that implements the [SELECT] statement. ^The second parameter is the
! 3249: ** column number. ^The leftmost column is number 0.
! 3250: **
! 3251: ** ^The returned string pointer is valid until either the [prepared statement]
! 3252: ** is destroyed by [sqlite3_finalize()] or until the statement is automatically
! 3253: ** reprepared by the first call to [sqlite3_step()] for a particular run
! 3254: ** or until the next call to
! 3255: ** sqlite3_column_name() or sqlite3_column_name16() on the same column.
! 3256: **
! 3257: ** ^If sqlite3_malloc() fails during the processing of either routine
! 3258: ** (for example during a conversion from UTF-8 to UTF-16) then a
! 3259: ** NULL pointer is returned.
! 3260: **
! 3261: ** ^The name of a result column is the value of the "AS" clause for
! 3262: ** that column, if there is an AS clause. If there is no AS clause
! 3263: ** then the name of the column is unspecified and may change from
! 3264: ** one release of SQLite to the next.
! 3265: */
! 3266: SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N);
! 3267: SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N);
! 3268:
! 3269: /*
! 3270: ** CAPI3REF: Source Of Data In A Query Result
! 3271: **
! 3272: ** ^These routines provide a means to determine the database, table, and
! 3273: ** table column that is the origin of a particular result column in
! 3274: ** [SELECT] statement.
! 3275: ** ^The name of the database or table or column can be returned as
! 3276: ** either a UTF-8 or UTF-16 string. ^The _database_ routines return
! 3277: ** the database name, the _table_ routines return the table name, and
! 3278: ** the origin_ routines return the column name.
! 3279: ** ^The returned string is valid until the [prepared statement] is destroyed
! 3280: ** using [sqlite3_finalize()] or until the statement is automatically
! 3281: ** reprepared by the first call to [sqlite3_step()] for a particular run
! 3282: ** or until the same information is requested
! 3283: ** again in a different encoding.
! 3284: **
! 3285: ** ^The names returned are the original un-aliased names of the
! 3286: ** database, table, and column.
! 3287: **
! 3288: ** ^The first argument to these interfaces is a [prepared statement].
! 3289: ** ^These functions return information about the Nth result column returned by
! 3290: ** the statement, where N is the second function argument.
! 3291: ** ^The left-most column is column 0 for these routines.
! 3292: **
! 3293: ** ^If the Nth column returned by the statement is an expression or
! 3294: ** subquery and is not a column value, then all of these functions return
! 3295: ** NULL. ^These routine might also return NULL if a memory allocation error
! 3296: ** occurs. ^Otherwise, they return the name of the attached database, table,
! 3297: ** or column that query result column was extracted from.
! 3298: **
! 3299: ** ^As with all other SQLite APIs, those whose names end with "16" return
! 3300: ** UTF-16 encoded strings and the other functions return UTF-8.
! 3301: **
! 3302: ** ^These APIs are only available if the library was compiled with the
! 3303: ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.
! 3304: **
! 3305: ** If two or more threads call one or more of these routines against the same
! 3306: ** prepared statement and column at the same time then the results are
! 3307: ** undefined.
! 3308: **
! 3309: ** If two or more threads call one or more
! 3310: ** [sqlite3_column_database_name | column metadata interfaces]
! 3311: ** for the same [prepared statement] and result column
! 3312: ** at the same time then the results are undefined.
! 3313: */
! 3314: SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int);
! 3315: SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int);
! 3316: SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int);
! 3317: SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int);
! 3318: SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int);
! 3319: SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int);
! 3320:
! 3321: /*
! 3322: ** CAPI3REF: Declared Datatype Of A Query Result
! 3323: **
! 3324: ** ^(The first parameter is a [prepared statement].
! 3325: ** If this statement is a [SELECT] statement and the Nth column of the
! 3326: ** returned result set of that [SELECT] is a table column (not an
! 3327: ** expression or subquery) then the declared type of the table
! 3328: ** column is returned.)^ ^If the Nth column of the result set is an
! 3329: ** expression or subquery, then a NULL pointer is returned.
! 3330: ** ^The returned string is always UTF-8 encoded.
! 3331: **
! 3332: ** ^(For example, given the database schema:
! 3333: **
! 3334: ** CREATE TABLE t1(c1 VARIANT);
! 3335: **
! 3336: ** and the following statement to be compiled:
! 3337: **
! 3338: ** SELECT c1 + 1, c1 FROM t1;
! 3339: **
! 3340: ** this routine would return the string "VARIANT" for the second result
! 3341: ** column (i==1), and a NULL pointer for the first result column (i==0).)^
! 3342: **
! 3343: ** ^SQLite uses dynamic run-time typing. ^So just because a column
! 3344: ** is declared to contain a particular type does not mean that the
! 3345: ** data stored in that column is of the declared type. SQLite is
! 3346: ** strongly typed, but the typing is dynamic not static. ^Type
! 3347: ** is associated with individual values, not with the containers
! 3348: ** used to hold those values.
! 3349: */
! 3350: SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int);
! 3351: SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int);
! 3352:
! 3353: /*
! 3354: ** CAPI3REF: Evaluate An SQL Statement
! 3355: **
! 3356: ** After a [prepared statement] has been prepared using either
! 3357: ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy
! 3358: ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function
! 3359: ** must be called one or more times to evaluate the statement.
! 3360: **
! 3361: ** The details of the behavior of the sqlite3_step() interface depend
! 3362: ** on whether the statement was prepared using the newer "v2" interface
! 3363: ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy
! 3364: ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the
! 3365: ** new "v2" interface is recommended for new applications but the legacy
! 3366: ** interface will continue to be supported.
! 3367: **
! 3368: ** ^In the legacy interface, the return value will be either [SQLITE_BUSY],
! 3369: ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].
! 3370: ** ^With the "v2" interface, any of the other [result codes] or
! 3371: ** [extended result codes] might be returned as well.
! 3372: **
! 3373: ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the
! 3374: ** database locks it needs to do its job. ^If the statement is a [COMMIT]
! 3375: ** or occurs outside of an explicit transaction, then you can retry the
! 3376: ** statement. If the statement is not a [COMMIT] and occurs within an
! 3377: ** explicit transaction then you should rollback the transaction before
! 3378: ** continuing.
! 3379: **
! 3380: ** ^[SQLITE_DONE] means that the statement has finished executing
! 3381: ** successfully. sqlite3_step() should not be called again on this virtual
! 3382: ** machine without first calling [sqlite3_reset()] to reset the virtual
! 3383: ** machine back to its initial state.
! 3384: **
! 3385: ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]
! 3386: ** is returned each time a new row of data is ready for processing by the
! 3387: ** caller. The values may be accessed using the [column access functions].
! 3388: ** sqlite3_step() is called again to retrieve the next row of data.
! 3389: **
! 3390: ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint
! 3391: ** violation) has occurred. sqlite3_step() should not be called again on
! 3392: ** the VM. More information may be found by calling [sqlite3_errmsg()].
! 3393: ** ^With the legacy interface, a more specific error code (for example,
! 3394: ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)
! 3395: ** can be obtained by calling [sqlite3_reset()] on the
! 3396: ** [prepared statement]. ^In the "v2" interface,
! 3397: ** the more specific error code is returned directly by sqlite3_step().
! 3398: **
! 3399: ** [SQLITE_MISUSE] means that the this routine was called inappropriately.
! 3400: ** Perhaps it was called on a [prepared statement] that has
! 3401: ** already been [sqlite3_finalize | finalized] or on one that had
! 3402: ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could
! 3403: ** be the case that the same database connection is being used by two or
! 3404: ** more threads at the same moment in time.
! 3405: **
! 3406: ** For all versions of SQLite up to and including 3.6.23.1, a call to
! 3407: ** [sqlite3_reset()] was required after sqlite3_step() returned anything
! 3408: ** other than [SQLITE_ROW] before any subsequent invocation of
! 3409: ** sqlite3_step(). Failure to reset the prepared statement using
! 3410: ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from
! 3411: ** sqlite3_step(). But after version 3.6.23.1, sqlite3_step() began
! 3412: ** calling [sqlite3_reset()] automatically in this circumstance rather
! 3413: ** than returning [SQLITE_MISUSE]. This is not considered a compatibility
! 3414: ** break because any application that ever receives an SQLITE_MISUSE error
! 3415: ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option
! 3416: ** can be used to restore the legacy behavior.
! 3417: **
! 3418: ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()
! 3419: ** API always returns a generic error code, [SQLITE_ERROR], following any
! 3420: ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call
! 3421: ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the
! 3422: ** specific [error codes] that better describes the error.
! 3423: ** We admit that this is a goofy design. The problem has been fixed
! 3424: ** with the "v2" interface. If you prepare all of your SQL statements
! 3425: ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead
! 3426: ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,
! 3427: ** then the more specific [error codes] are returned directly
! 3428: ** by sqlite3_step(). The use of the "v2" interface is recommended.
! 3429: */
! 3430: SQLITE_API int sqlite3_step(sqlite3_stmt*);
! 3431:
! 3432: /*
! 3433: ** CAPI3REF: Number of columns in a result set
! 3434: **
! 3435: ** ^The sqlite3_data_count(P) interface returns the number of columns in the
! 3436: ** current row of the result set of [prepared statement] P.
! 3437: ** ^If prepared statement P does not have results ready to return
! 3438: ** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of
! 3439: ** interfaces) then sqlite3_data_count(P) returns 0.
! 3440: ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.
! 3441: ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to
! 3442: ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)
! 3443: ** will return non-zero if previous call to [sqlite3_step](P) returned
! 3444: ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]
! 3445: ** where it always returns zero since each step of that multi-step
! 3446: ** pragma returns 0 columns of data.
! 3447: **
! 3448: ** See also: [sqlite3_column_count()]
! 3449: */
! 3450: SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt);
! 3451:
! 3452: /*
! 3453: ** CAPI3REF: Fundamental Datatypes
! 3454: ** KEYWORDS: SQLITE_TEXT
! 3455: **
! 3456: ** ^(Every value in SQLite has one of five fundamental datatypes:
! 3457: **
! 3458: ** <ul>
! 3459: ** <li> 64-bit signed integer
! 3460: ** <li> 64-bit IEEE floating point number
! 3461: ** <li> string
! 3462: ** <li> BLOB
! 3463: ** <li> NULL
! 3464: ** </ul>)^
! 3465: **
! 3466: ** These constants are codes for each of those types.
! 3467: **
! 3468: ** Note that the SQLITE_TEXT constant was also used in SQLite version 2
! 3469: ** for a completely different meaning. Software that links against both
! 3470: ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not
! 3471: ** SQLITE_TEXT.
! 3472: */
! 3473: #define SQLITE_INTEGER 1
! 3474: #define SQLITE_FLOAT 2
! 3475: #define SQLITE_BLOB 4
! 3476: #define SQLITE_NULL 5
! 3477: #ifdef SQLITE_TEXT
! 3478: # undef SQLITE_TEXT
! 3479: #else
! 3480: # define SQLITE_TEXT 3
! 3481: #endif
! 3482: #define SQLITE3_TEXT 3
! 3483:
! 3484: /*
! 3485: ** CAPI3REF: Result Values From A Query
! 3486: ** KEYWORDS: {column access functions}
! 3487: **
! 3488: ** These routines form the "result set" interface.
! 3489: **
! 3490: ** ^These routines return information about a single column of the current
! 3491: ** result row of a query. ^In every case the first argument is a pointer
! 3492: ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]
! 3493: ** that was returned from [sqlite3_prepare_v2()] or one of its variants)
! 3494: ** and the second argument is the index of the column for which information
! 3495: ** should be returned. ^The leftmost column of the result set has the index 0.
! 3496: ** ^The number of columns in the result can be determined using
! 3497: ** [sqlite3_column_count()].
! 3498: **
! 3499: ** If the SQL statement does not currently point to a valid row, or if the
! 3500: ** column index is out of range, the result is undefined.
! 3501: ** These routines may only be called when the most recent call to
! 3502: ** [sqlite3_step()] has returned [SQLITE_ROW] and neither
! 3503: ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.
! 3504: ** If any of these routines are called after [sqlite3_reset()] or
! 3505: ** [sqlite3_finalize()] or after [sqlite3_step()] has returned
! 3506: ** something other than [SQLITE_ROW], the results are undefined.
! 3507: ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]
! 3508: ** are called from a different thread while any of these routines
! 3509: ** are pending, then the results are undefined.
! 3510: **
! 3511: ** ^The sqlite3_column_type() routine returns the
! 3512: ** [SQLITE_INTEGER | datatype code] for the initial data type
! 3513: ** of the result column. ^The returned value is one of [SQLITE_INTEGER],
! 3514: ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value
! 3515: ** returned by sqlite3_column_type() is only meaningful if no type
! 3516: ** conversions have occurred as described below. After a type conversion,
! 3517: ** the value returned by sqlite3_column_type() is undefined. Future
! 3518: ** versions of SQLite may change the behavior of sqlite3_column_type()
! 3519: ** following a type conversion.
! 3520: **
! 3521: ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()
! 3522: ** routine returns the number of bytes in that BLOB or string.
! 3523: ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts
! 3524: ** the string to UTF-8 and then returns the number of bytes.
! 3525: ** ^If the result is a numeric value then sqlite3_column_bytes() uses
! 3526: ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns
! 3527: ** the number of bytes in that string.
! 3528: ** ^If the result is NULL, then sqlite3_column_bytes() returns zero.
! 3529: **
! 3530: ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()
! 3531: ** routine returns the number of bytes in that BLOB or string.
! 3532: ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts
! 3533: ** the string to UTF-16 and then returns the number of bytes.
! 3534: ** ^If the result is a numeric value then sqlite3_column_bytes16() uses
! 3535: ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns
! 3536: ** the number of bytes in that string.
! 3537: ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.
! 3538: **
! 3539: ** ^The values returned by [sqlite3_column_bytes()] and
! 3540: ** [sqlite3_column_bytes16()] do not include the zero terminators at the end
! 3541: ** of the string. ^For clarity: the values returned by
! 3542: ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of
! 3543: ** bytes in the string, not the number of characters.
! 3544: **
! 3545: ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),
! 3546: ** even empty strings, are always zero-terminated. ^The return
! 3547: ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.
! 3548: **
! 3549: ** ^The object returned by [sqlite3_column_value()] is an
! 3550: ** [unprotected sqlite3_value] object. An unprotected sqlite3_value object
! 3551: ** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()].
! 3552: ** If the [unprotected sqlite3_value] object returned by
! 3553: ** [sqlite3_column_value()] is used in any other way, including calls
! 3554: ** to routines like [sqlite3_value_int()], [sqlite3_value_text()],
! 3555: ** or [sqlite3_value_bytes()], then the behavior is undefined.
! 3556: **
! 3557: ** These routines attempt to convert the value where appropriate. ^For
! 3558: ** example, if the internal representation is FLOAT and a text result
! 3559: ** is requested, [sqlite3_snprintf()] is used internally to perform the
! 3560: ** conversion automatically. ^(The following table details the conversions
! 3561: ** that are applied:
! 3562: **
! 3563: ** <blockquote>
! 3564: ** <table border="1">
! 3565: ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion
! 3566: **
! 3567: ** <tr><td> NULL <td> INTEGER <td> Result is 0
! 3568: ** <tr><td> NULL <td> FLOAT <td> Result is 0.0
! 3569: ** <tr><td> NULL <td> TEXT <td> Result is NULL pointer
! 3570: ** <tr><td> NULL <td> BLOB <td> Result is NULL pointer
! 3571: ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float
! 3572: ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer
! 3573: ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT
! 3574: ** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer
! 3575: ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float
! 3576: ** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT
! 3577: ** <tr><td> TEXT <td> INTEGER <td> Use atoi()
! 3578: ** <tr><td> TEXT <td> FLOAT <td> Use atof()
! 3579: ** <tr><td> TEXT <td> BLOB <td> No change
! 3580: ** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi()
! 3581: ** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof()
! 3582: ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed
! 3583: ** </table>
! 3584: ** </blockquote>)^
! 3585: **
! 3586: ** The table above makes reference to standard C library functions atoi()
! 3587: ** and atof(). SQLite does not really use these functions. It has its
! 3588: ** own equivalent internal routines. The atoi() and atof() names are
! 3589: ** used in the table for brevity and because they are familiar to most
! 3590: ** C programmers.
! 3591: **
! 3592: ** Note that when type conversions occur, pointers returned by prior
! 3593: ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or
! 3594: ** sqlite3_column_text16() may be invalidated.
! 3595: ** Type conversions and pointer invalidations might occur
! 3596: ** in the following cases:
! 3597: **
! 3598: ** <ul>
! 3599: ** <li> The initial content is a BLOB and sqlite3_column_text() or
! 3600: ** sqlite3_column_text16() is called. A zero-terminator might
! 3601: ** need to be added to the string.</li>
! 3602: ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or
! 3603: ** sqlite3_column_text16() is called. The content must be converted
! 3604: ** to UTF-16.</li>
! 3605: ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or
! 3606: ** sqlite3_column_text() is called. The content must be converted
! 3607: ** to UTF-8.</li>
! 3608: ** </ul>
! 3609: **
! 3610: ** ^Conversions between UTF-16be and UTF-16le are always done in place and do
! 3611: ** not invalidate a prior pointer, though of course the content of the buffer
! 3612: ** that the prior pointer references will have been modified. Other kinds
! 3613: ** of conversion are done in place when it is possible, but sometimes they
! 3614: ** are not possible and in those cases prior pointers are invalidated.
! 3615: **
! 3616: ** The safest and easiest to remember policy is to invoke these routines
! 3617: ** in one of the following ways:
! 3618: **
! 3619: ** <ul>
! 3620: ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>
! 3621: ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>
! 3622: ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>
! 3623: ** </ul>
! 3624: **
! 3625: ** In other words, you should call sqlite3_column_text(),
! 3626: ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result
! 3627: ** into the desired format, then invoke sqlite3_column_bytes() or
! 3628: ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls
! 3629: ** to sqlite3_column_text() or sqlite3_column_blob() with calls to
! 3630: ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()
! 3631: ** with calls to sqlite3_column_bytes().
! 3632: **
! 3633: ** ^The pointers returned are valid until a type conversion occurs as
! 3634: ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or
! 3635: ** [sqlite3_finalize()] is called. ^The memory space used to hold strings
! 3636: ** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned
! 3637: ** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into
! 3638: ** [sqlite3_free()].
! 3639: **
! 3640: ** ^(If a memory allocation error occurs during the evaluation of any
! 3641: ** of these routines, a default value is returned. The default value
! 3642: ** is either the integer 0, the floating point number 0.0, or a NULL
! 3643: ** pointer. Subsequent calls to [sqlite3_errcode()] will return
! 3644: ** [SQLITE_NOMEM].)^
! 3645: */
! 3646: SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol);
! 3647: SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol);
! 3648: SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol);
! 3649: SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol);
! 3650: SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol);
! 3651: SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
! 3652: SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
! 3653: SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
! 3654: SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol);
! 3655: SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol);
! 3656:
! 3657: /*
! 3658: ** CAPI3REF: Destroy A Prepared Statement Object
! 3659: **
! 3660: ** ^The sqlite3_finalize() function is called to delete a [prepared statement].
! 3661: ** ^If the most recent evaluation of the statement encountered no errors
! 3662: ** or if the statement is never been evaluated, then sqlite3_finalize() returns
! 3663: ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then
! 3664: ** sqlite3_finalize(S) returns the appropriate [error code] or
! 3665: ** [extended error code].
! 3666: **
! 3667: ** ^The sqlite3_finalize(S) routine can be called at any point during
! 3668: ** the life cycle of [prepared statement] S:
! 3669: ** before statement S is ever evaluated, after
! 3670: ** one or more calls to [sqlite3_reset()], or after any call
! 3671: ** to [sqlite3_step()] regardless of whether or not the statement has
! 3672: ** completed execution.
! 3673: **
! 3674: ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.
! 3675: **
! 3676: ** The application must finalize every [prepared statement] in order to avoid
! 3677: ** resource leaks. It is a grievous error for the application to try to use
! 3678: ** a prepared statement after it has been finalized. Any use of a prepared
! 3679: ** statement after it has been finalized can result in undefined and
! 3680: ** undesirable behavior such as segfaults and heap corruption.
! 3681: */
! 3682: SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt);
! 3683:
! 3684: /*
! 3685: ** CAPI3REF: Reset A Prepared Statement Object
! 3686: **
! 3687: ** The sqlite3_reset() function is called to reset a [prepared statement]
! 3688: ** object back to its initial state, ready to be re-executed.
! 3689: ** ^Any SQL statement variables that had values bound to them using
! 3690: ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.
! 3691: ** Use [sqlite3_clear_bindings()] to reset the bindings.
! 3692: **
! 3693: ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S
! 3694: ** back to the beginning of its program.
! 3695: **
! 3696: ** ^If the most recent call to [sqlite3_step(S)] for the
! 3697: ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],
! 3698: ** or if [sqlite3_step(S)] has never before been called on S,
! 3699: ** then [sqlite3_reset(S)] returns [SQLITE_OK].
! 3700: **
! 3701: ** ^If the most recent call to [sqlite3_step(S)] for the
! 3702: ** [prepared statement] S indicated an error, then
! 3703: ** [sqlite3_reset(S)] returns an appropriate [error code].
! 3704: **
! 3705: ** ^The [sqlite3_reset(S)] interface does not change the values
! 3706: ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.
! 3707: */
! 3708: SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt);
! 3709:
! 3710: /*
! 3711: ** CAPI3REF: Create Or Redefine SQL Functions
! 3712: ** KEYWORDS: {function creation routines}
! 3713: ** KEYWORDS: {application-defined SQL function}
! 3714: ** KEYWORDS: {application-defined SQL functions}
! 3715: **
! 3716: ** ^These functions (collectively known as "function creation routines")
! 3717: ** are used to add SQL functions or aggregates or to redefine the behavior
! 3718: ** of existing SQL functions or aggregates. The only differences between
! 3719: ** these routines are the text encoding expected for
! 3720: ** the second parameter (the name of the function being created)
! 3721: ** and the presence or absence of a destructor callback for
! 3722: ** the application data pointer.
! 3723: **
! 3724: ** ^The first parameter is the [database connection] to which the SQL
! 3725: ** function is to be added. ^If an application uses more than one database
! 3726: ** connection then application-defined SQL functions must be added
! 3727: ** to each database connection separately.
! 3728: **
! 3729: ** ^The second parameter is the name of the SQL function to be created or
! 3730: ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8
! 3731: ** representation, exclusive of the zero-terminator. ^Note that the name
! 3732: ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes.
! 3733: ** ^Any attempt to create a function with a longer name
! 3734: ** will result in [SQLITE_MISUSE] being returned.
! 3735: **
! 3736: ** ^The third parameter (nArg)
! 3737: ** is the number of arguments that the SQL function or
! 3738: ** aggregate takes. ^If this parameter is -1, then the SQL function or
! 3739: ** aggregate may take any number of arguments between 0 and the limit
! 3740: ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third
! 3741: ** parameter is less than -1 or greater than 127 then the behavior is
! 3742: ** undefined.
! 3743: **
! 3744: ** ^The fourth parameter, eTextRep, specifies what
! 3745: ** [SQLITE_UTF8 | text encoding] this SQL function prefers for
! 3746: ** its parameters. Every SQL function implementation must be able to work
! 3747: ** with UTF-8, UTF-16le, or UTF-16be. But some implementations may be
! 3748: ** more efficient with one encoding than another. ^An application may
! 3749: ** invoke sqlite3_create_function() or sqlite3_create_function16() multiple
! 3750: ** times with the same function but with different values of eTextRep.
! 3751: ** ^When multiple implementations of the same function are available, SQLite
! 3752: ** will pick the one that involves the least amount of data conversion.
! 3753: ** If there is only a single implementation which does not care what text
! 3754: ** encoding is used, then the fourth argument should be [SQLITE_ANY].
! 3755: **
! 3756: ** ^(The fifth parameter is an arbitrary pointer. The implementation of the
! 3757: ** function can gain access to this pointer using [sqlite3_user_data()].)^
! 3758: **
! 3759: ** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are
! 3760: ** pointers to C-language functions that implement the SQL function or
! 3761: ** aggregate. ^A scalar SQL function requires an implementation of the xFunc
! 3762: ** callback only; NULL pointers must be passed as the xStep and xFinal
! 3763: ** parameters. ^An aggregate SQL function requires an implementation of xStep
! 3764: ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing
! 3765: ** SQL function or aggregate, pass NULL pointers for all three function
! 3766: ** callbacks.
! 3767: **
! 3768: ** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,
! 3769: ** then it is destructor for the application data pointer.
! 3770: ** The destructor is invoked when the function is deleted, either by being
! 3771: ** overloaded or when the database connection closes.)^
! 3772: ** ^The destructor is also invoked if the call to
! 3773: ** sqlite3_create_function_v2() fails.
! 3774: ** ^When the destructor callback of the tenth parameter is invoked, it
! 3775: ** is passed a single argument which is a copy of the application data
! 3776: ** pointer which was the fifth parameter to sqlite3_create_function_v2().
! 3777: **
! 3778: ** ^It is permitted to register multiple implementations of the same
! 3779: ** functions with the same name but with either differing numbers of
! 3780: ** arguments or differing preferred text encodings. ^SQLite will use
! 3781: ** the implementation that most closely matches the way in which the
! 3782: ** SQL function is used. ^A function implementation with a non-negative
! 3783: ** nArg parameter is a better match than a function implementation with
! 3784: ** a negative nArg. ^A function where the preferred text encoding
! 3785: ** matches the database encoding is a better
! 3786: ** match than a function where the encoding is different.
! 3787: ** ^A function where the encoding difference is between UTF16le and UTF16be
! 3788: ** is a closer match than a function where the encoding difference is
! 3789: ** between UTF8 and UTF16.
! 3790: **
! 3791: ** ^Built-in functions may be overloaded by new application-defined functions.
! 3792: **
! 3793: ** ^An application-defined function is permitted to call other
! 3794: ** SQLite interfaces. However, such calls must not
! 3795: ** close the database connection nor finalize or reset the prepared
! 3796: ** statement in which the function is running.
! 3797: */
! 3798: SQLITE_API int sqlite3_create_function(
! 3799: sqlite3 *db,
! 3800: const char *zFunctionName,
! 3801: int nArg,
! 3802: int eTextRep,
! 3803: void *pApp,
! 3804: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
! 3805: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
! 3806: void (*xFinal)(sqlite3_context*)
! 3807: );
! 3808: SQLITE_API int sqlite3_create_function16(
! 3809: sqlite3 *db,
! 3810: const void *zFunctionName,
! 3811: int nArg,
! 3812: int eTextRep,
! 3813: void *pApp,
! 3814: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
! 3815: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
! 3816: void (*xFinal)(sqlite3_context*)
! 3817: );
! 3818: SQLITE_API int sqlite3_create_function_v2(
! 3819: sqlite3 *db,
! 3820: const char *zFunctionName,
! 3821: int nArg,
! 3822: int eTextRep,
! 3823: void *pApp,
! 3824: void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
! 3825: void (*xStep)(sqlite3_context*,int,sqlite3_value**),
! 3826: void (*xFinal)(sqlite3_context*),
! 3827: void(*xDestroy)(void*)
! 3828: );
! 3829:
! 3830: /*
! 3831: ** CAPI3REF: Text Encodings
! 3832: **
! 3833: ** These constant define integer codes that represent the various
! 3834: ** text encodings supported by SQLite.
! 3835: */
! 3836: #define SQLITE_UTF8 1
! 3837: #define SQLITE_UTF16LE 2
! 3838: #define SQLITE_UTF16BE 3
! 3839: #define SQLITE_UTF16 4 /* Use native byte order */
! 3840: #define SQLITE_ANY 5 /* sqlite3_create_function only */
! 3841: #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */
! 3842:
! 3843: /*
! 3844: ** CAPI3REF: Deprecated Functions
! 3845: ** DEPRECATED
! 3846: **
! 3847: ** These functions are [deprecated]. In order to maintain
! 3848: ** backwards compatibility with older code, these functions continue
! 3849: ** to be supported. However, new applications should avoid
! 3850: ** the use of these functions. To help encourage people to avoid
! 3851: ** using these functions, we are not going to tell you what they do.
! 3852: */
! 3853: #ifndef SQLITE_OMIT_DEPRECATED
! 3854: SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
! 3855: SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
! 3856: SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
! 3857: SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
! 3858: SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
! 3859: SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
! 3860: #endif
! 3861:
! 3862: /*
! 3863: ** CAPI3REF: Obtaining SQL Function Parameter Values
! 3864: **
! 3865: ** The C-language implementation of SQL functions and aggregates uses
! 3866: ** this set of interface routines to access the parameter values on
! 3867: ** the function or aggregate.
! 3868: **
! 3869: ** The xFunc (for scalar functions) or xStep (for aggregates) parameters
! 3870: ** to [sqlite3_create_function()] and [sqlite3_create_function16()]
! 3871: ** define callbacks that implement the SQL functions and aggregates.
! 3872: ** The 3rd parameter to these callbacks is an array of pointers to
! 3873: ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for
! 3874: ** each parameter to the SQL function. These routines are used to
! 3875: ** extract values from the [sqlite3_value] objects.
! 3876: **
! 3877: ** These routines work only with [protected sqlite3_value] objects.
! 3878: ** Any attempt to use these routines on an [unprotected sqlite3_value]
! 3879: ** object results in undefined behavior.
! 3880: **
! 3881: ** ^These routines work just like the corresponding [column access functions]
! 3882: ** except that these routines take a single [protected sqlite3_value] object
! 3883: ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.
! 3884: **
! 3885: ** ^The sqlite3_value_text16() interface extracts a UTF-16 string
! 3886: ** in the native byte-order of the host machine. ^The
! 3887: ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces
! 3888: ** extract UTF-16 strings as big-endian and little-endian respectively.
! 3889: **
! 3890: ** ^(The sqlite3_value_numeric_type() interface attempts to apply
! 3891: ** numeric affinity to the value. This means that an attempt is
! 3892: ** made to convert the value to an integer or floating point. If
! 3893: ** such a conversion is possible without loss of information (in other
! 3894: ** words, if the value is a string that looks like a number)
! 3895: ** then the conversion is performed. Otherwise no conversion occurs.
! 3896: ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
! 3897: **
! 3898: ** Please pay particular attention to the fact that the pointer returned
! 3899: ** from [sqlite3_value_blob()], [sqlite3_value_text()], or
! 3900: ** [sqlite3_value_text16()] can be invalidated by a subsequent call to
! 3901: ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],
! 3902: ** or [sqlite3_value_text16()].
! 3903: **
! 3904: ** These routines must be called from the same thread as
! 3905: ** the SQL function that supplied the [sqlite3_value*] parameters.
! 3906: */
! 3907: SQLITE_API const void *sqlite3_value_blob(sqlite3_value*);
! 3908: SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
! 3909: SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
! 3910: SQLITE_API double sqlite3_value_double(sqlite3_value*);
! 3911: SQLITE_API int sqlite3_value_int(sqlite3_value*);
! 3912: SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*);
! 3913: SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*);
! 3914: SQLITE_API const void *sqlite3_value_text16(sqlite3_value*);
! 3915: SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*);
! 3916: SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
! 3917: SQLITE_API int sqlite3_value_type(sqlite3_value*);
! 3918: SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
! 3919:
! 3920: /*
! 3921: ** CAPI3REF: Obtain Aggregate Function Context
! 3922: **
! 3923: ** Implementations of aggregate SQL functions use this
! 3924: ** routine to allocate memory for storing their state.
! 3925: **
! 3926: ** ^The first time the sqlite3_aggregate_context(C,N) routine is called
! 3927: ** for a particular aggregate function, SQLite
! 3928: ** allocates N of memory, zeroes out that memory, and returns a pointer
! 3929: ** to the new memory. ^On second and subsequent calls to
! 3930: ** sqlite3_aggregate_context() for the same aggregate function instance,
! 3931: ** the same buffer is returned. Sqlite3_aggregate_context() is normally
! 3932: ** called once for each invocation of the xStep callback and then one
! 3933: ** last time when the xFinal callback is invoked. ^(When no rows match
! 3934: ** an aggregate query, the xStep() callback of the aggregate function
! 3935: ** implementation is never called and xFinal() is called exactly once.
! 3936: ** In those cases, sqlite3_aggregate_context() might be called for the
! 3937: ** first time from within xFinal().)^
! 3938: **
! 3939: ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
! 3940: ** less than or equal to zero or if a memory allocate error occurs.
! 3941: **
! 3942: ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
! 3943: ** determined by the N parameter on first successful call. Changing the
! 3944: ** value of N in subsequent call to sqlite3_aggregate_context() within
! 3945: ** the same aggregate function instance will not resize the memory
! 3946: ** allocation.)^
! 3947: **
! 3948: ** ^SQLite automatically frees the memory allocated by
! 3949: ** sqlite3_aggregate_context() when the aggregate query concludes.
! 3950: **
! 3951: ** The first parameter must be a copy of the
! 3952: ** [sqlite3_context | SQL function context] that is the first parameter
! 3953: ** to the xStep or xFinal callback routine that implements the aggregate
! 3954: ** function.
! 3955: **
! 3956: ** This routine must be called from the same thread in which
! 3957: ** the aggregate SQL function is running.
! 3958: */
! 3959: SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes);
! 3960:
! 3961: /*
! 3962: ** CAPI3REF: User Data For Functions
! 3963: **
! 3964: ** ^The sqlite3_user_data() interface returns a copy of
! 3965: ** the pointer that was the pUserData parameter (the 5th parameter)
! 3966: ** of the [sqlite3_create_function()]
! 3967: ** and [sqlite3_create_function16()] routines that originally
! 3968: ** registered the application defined function.
! 3969: **
! 3970: ** This routine must be called from the same thread in which
! 3971: ** the application-defined function is running.
! 3972: */
! 3973: SQLITE_API void *sqlite3_user_data(sqlite3_context*);
! 3974:
! 3975: /*
! 3976: ** CAPI3REF: Database Connection For Functions
! 3977: **
! 3978: ** ^The sqlite3_context_db_handle() interface returns a copy of
! 3979: ** the pointer to the [database connection] (the 1st parameter)
! 3980: ** of the [sqlite3_create_function()]
! 3981: ** and [sqlite3_create_function16()] routines that originally
! 3982: ** registered the application defined function.
! 3983: */
! 3984: SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
! 3985:
! 3986: /*
! 3987: ** CAPI3REF: Function Auxiliary Data
! 3988: **
! 3989: ** The following two functions may be used by scalar SQL functions to
! 3990: ** associate metadata with argument values. If the same value is passed to
! 3991: ** multiple invocations of the same SQL function during query execution, under
! 3992: ** some circumstances the associated metadata may be preserved. This may
! 3993: ** be used, for example, to add a regular-expression matching scalar
! 3994: ** function. The compiled version of the regular expression is stored as
! 3995: ** metadata associated with the SQL value passed as the regular expression
! 3996: ** pattern. The compiled regular expression can be reused on multiple
! 3997: ** invocations of the same function so that the original pattern string
! 3998: ** does not need to be recompiled on each invocation.
! 3999: **
! 4000: ** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
! 4001: ** associated by the sqlite3_set_auxdata() function with the Nth argument
! 4002: ** value to the application-defined function. ^If no metadata has been ever
! 4003: ** been set for the Nth argument of the function, or if the corresponding
! 4004: ** function parameter has changed since the meta-data was set,
! 4005: ** then sqlite3_get_auxdata() returns a NULL pointer.
! 4006: **
! 4007: ** ^The sqlite3_set_auxdata() interface saves the metadata
! 4008: ** pointed to by its 3rd parameter as the metadata for the N-th
! 4009: ** argument of the application-defined function. Subsequent
! 4010: ** calls to sqlite3_get_auxdata() might return this data, if it has
! 4011: ** not been destroyed.
! 4012: ** ^If it is not NULL, SQLite will invoke the destructor
! 4013: ** function given by the 4th parameter to sqlite3_set_auxdata() on
! 4014: ** the metadata when the corresponding function parameter changes
! 4015: ** or when the SQL statement completes, whichever comes first.
! 4016: **
! 4017: ** SQLite is free to call the destructor and drop metadata on any
! 4018: ** parameter of any function at any time. ^The only guarantee is that
! 4019: ** the destructor will be called before the metadata is dropped.
! 4020: **
! 4021: ** ^(In practice, metadata is preserved between function calls for
! 4022: ** expressions that are constant at compile time. This includes literal
! 4023: ** values and [parameters].)^
! 4024: **
! 4025: ** These routines must be called from the same thread in which
! 4026: ** the SQL function is running.
! 4027: */
! 4028: SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N);
! 4029: SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*));
! 4030:
! 4031:
! 4032: /*
! 4033: ** CAPI3REF: Constants Defining Special Destructor Behavior
! 4034: **
! 4035: ** These are special values for the destructor that is passed in as the
! 4036: ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor
! 4037: ** argument is SQLITE_STATIC, it means that the content pointer is constant
! 4038: ** and will never change. It does not need to be destroyed. ^The
! 4039: ** SQLITE_TRANSIENT value means that the content will likely change in
! 4040: ** the near future and that SQLite should make its own private copy of
! 4041: ** the content before returning.
! 4042: **
! 4043: ** The typedef is necessary to work around problems in certain
! 4044: ** C++ compilers. See ticket #2191.
! 4045: */
! 4046: typedef void (*sqlite3_destructor_type)(void*);
! 4047: #define SQLITE_STATIC ((sqlite3_destructor_type)0)
! 4048: #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
! 4049:
! 4050: /*
! 4051: ** CAPI3REF: Setting The Result Of An SQL Function
! 4052: **
! 4053: ** These routines are used by the xFunc or xFinal callbacks that
! 4054: ** implement SQL functions and aggregates. See
! 4055: ** [sqlite3_create_function()] and [sqlite3_create_function16()]
! 4056: ** for additional information.
! 4057: **
! 4058: ** These functions work very much like the [parameter binding] family of
! 4059: ** functions used to bind values to host parameters in prepared statements.
! 4060: ** Refer to the [SQL parameter] documentation for additional information.
! 4061: **
! 4062: ** ^The sqlite3_result_blob() interface sets the result from
! 4063: ** an application-defined function to be the BLOB whose content is pointed
! 4064: ** to by the second parameter and which is N bytes long where N is the
! 4065: ** third parameter.
! 4066: **
! 4067: ** ^The sqlite3_result_zeroblob() interfaces set the result of
! 4068: ** the application-defined function to be a BLOB containing all zero
! 4069: ** bytes and N bytes in size, where N is the value of the 2nd parameter.
! 4070: **
! 4071: ** ^The sqlite3_result_double() interface sets the result from
! 4072: ** an application-defined function to be a floating point value specified
! 4073: ** by its 2nd argument.
! 4074: **
! 4075: ** ^The sqlite3_result_error() and sqlite3_result_error16() functions
! 4076: ** cause the implemented SQL function to throw an exception.
! 4077: ** ^SQLite uses the string pointed to by the
! 4078: ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()
! 4079: ** as the text of an error message. ^SQLite interprets the error
! 4080: ** message string from sqlite3_result_error() as UTF-8. ^SQLite
! 4081: ** interprets the string from sqlite3_result_error16() as UTF-16 in native
! 4082: ** byte order. ^If the third parameter to sqlite3_result_error()
! 4083: ** or sqlite3_result_error16() is negative then SQLite takes as the error
! 4084: ** message all text up through the first zero character.
! 4085: ** ^If the third parameter to sqlite3_result_error() or
! 4086: ** sqlite3_result_error16() is non-negative then SQLite takes that many
! 4087: ** bytes (not characters) from the 2nd parameter as the error message.
! 4088: ** ^The sqlite3_result_error() and sqlite3_result_error16()
! 4089: ** routines make a private copy of the error message text before
! 4090: ** they return. Hence, the calling function can deallocate or
! 4091: ** modify the text after they return without harm.
! 4092: ** ^The sqlite3_result_error_code() function changes the error code
! 4093: ** returned by SQLite as a result of an error in a function. ^By default,
! 4094: ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()
! 4095: ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
! 4096: **
! 4097: ** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
! 4098: ** indicating that a string or BLOB is too long to represent.
! 4099: **
! 4100: ** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
! 4101: ** indicating that a memory allocation failed.
! 4102: **
! 4103: ** ^The sqlite3_result_int() interface sets the return value
! 4104: ** of the application-defined function to be the 32-bit signed integer
! 4105: ** value given in the 2nd argument.
! 4106: ** ^The sqlite3_result_int64() interface sets the return value
! 4107: ** of the application-defined function to be the 64-bit signed integer
! 4108: ** value given in the 2nd argument.
! 4109: **
! 4110: ** ^The sqlite3_result_null() interface sets the return value
! 4111: ** of the application-defined function to be NULL.
! 4112: **
! 4113: ** ^The sqlite3_result_text(), sqlite3_result_text16(),
! 4114: ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces
! 4115: ** set the return value of the application-defined function to be
! 4116: ** a text string which is represented as UTF-8, UTF-16 native byte order,
! 4117: ** UTF-16 little endian, or UTF-16 big endian, respectively.
! 4118: ** ^SQLite takes the text result from the application from
! 4119: ** the 2nd parameter of the sqlite3_result_text* interfaces.
! 4120: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
! 4121: ** is negative, then SQLite takes result text from the 2nd parameter
! 4122: ** through the first zero character.
! 4123: ** ^If the 3rd parameter to the sqlite3_result_text* interfaces
! 4124: ** is non-negative, then as many bytes (not characters) of the text
! 4125: ** pointed to by the 2nd parameter are taken as the application-defined
! 4126: ** function result. If the 3rd parameter is non-negative, then it
! 4127: ** must be the byte offset into the string where the NUL terminator would
! 4128: ** appear if the string where NUL terminated. If any NUL characters occur
! 4129: ** in the string at a byte offset that is less than the value of the 3rd
! 4130: ** parameter, then the resulting string will contain embedded NULs and the
! 4131: ** result of expressions operating on strings with embedded NULs is undefined.
! 4132: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
! 4133: ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that
! 4134: ** function as the destructor on the text or BLOB result when it has
! 4135: ** finished using that result.
! 4136: ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to
! 4137: ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite
! 4138: ** assumes that the text or BLOB result is in constant space and does not
! 4139: ** copy the content of the parameter nor call a destructor on the content
! 4140: ** when it has finished using that result.
! 4141: ** ^If the 4th parameter to the sqlite3_result_text* interfaces
! 4142: ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT
! 4143: ** then SQLite makes a copy of the result into space obtained from
! 4144: ** from [sqlite3_malloc()] before it returns.
! 4145: **
! 4146: ** ^The sqlite3_result_value() interface sets the result of
! 4147: ** the application-defined function to be a copy the
! 4148: ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The
! 4149: ** sqlite3_result_value() interface makes a copy of the [sqlite3_value]
! 4150: ** so that the [sqlite3_value] specified in the parameter may change or
! 4151: ** be deallocated after sqlite3_result_value() returns without harm.
! 4152: ** ^A [protected sqlite3_value] object may always be used where an
! 4153: ** [unprotected sqlite3_value] object is required, so either
! 4154: ** kind of [sqlite3_value] object can be used with this interface.
! 4155: **
! 4156: ** If these routines are called from within the different thread
! 4157: ** than the one containing the application-defined function that received
! 4158: ** the [sqlite3_context] pointer, the results are undefined.
! 4159: */
! 4160: SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*));
! 4161: SQLITE_API void sqlite3_result_double(sqlite3_context*, double);
! 4162: SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int);
! 4163: SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int);
! 4164: SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*);
! 4165: SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*);
! 4166: SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int);
! 4167: SQLITE_API void sqlite3_result_int(sqlite3_context*, int);
! 4168: SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64);
! 4169: SQLITE_API void sqlite3_result_null(sqlite3_context*);
! 4170: SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*));
! 4171: SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*));
! 4172: SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*));
! 4173: SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*));
! 4174: SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*);
! 4175: SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n);
! 4176:
! 4177: /*
! 4178: ** CAPI3REF: Define New Collating Sequences
! 4179: **
! 4180: ** ^These functions add, remove, or modify a [collation] associated
! 4181: ** with the [database connection] specified as the first argument.
! 4182: **
! 4183: ** ^The name of the collation is a UTF-8 string
! 4184: ** for sqlite3_create_collation() and sqlite3_create_collation_v2()
! 4185: ** and a UTF-16 string in native byte order for sqlite3_create_collation16().
! 4186: ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are
! 4187: ** considered to be the same name.
! 4188: **
! 4189: ** ^(The third argument (eTextRep) must be one of the constants:
! 4190: ** <ul>
! 4191: ** <li> [SQLITE_UTF8],
! 4192: ** <li> [SQLITE_UTF16LE],
! 4193: ** <li> [SQLITE_UTF16BE],
! 4194: ** <li> [SQLITE_UTF16], or
! 4195: ** <li> [SQLITE_UTF16_ALIGNED].
! 4196: ** </ul>)^
! 4197: ** ^The eTextRep argument determines the encoding of strings passed
! 4198: ** to the collating function callback, xCallback.
! 4199: ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep
! 4200: ** force strings to be UTF16 with native byte order.
! 4201: ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin
! 4202: ** on an even byte address.
! 4203: **
! 4204: ** ^The fourth argument, pArg, is an application data pointer that is passed
! 4205: ** through as the first argument to the collating function callback.
! 4206: **
! 4207: ** ^The fifth argument, xCallback, is a pointer to the collating function.
! 4208: ** ^Multiple collating functions can be registered using the same name but
! 4209: ** with different eTextRep parameters and SQLite will use whichever
! 4210: ** function requires the least amount of data transformation.
! 4211: ** ^If the xCallback argument is NULL then the collating function is
! 4212: ** deleted. ^When all collating functions having the same name are deleted,
! 4213: ** that collation is no longer usable.
! 4214: **
! 4215: ** ^The collating function callback is invoked with a copy of the pArg
! 4216: ** application data pointer and with two strings in the encoding specified
! 4217: ** by the eTextRep argument. The collating function must return an
! 4218: ** integer that is negative, zero, or positive
! 4219: ** if the first string is less than, equal to, or greater than the second,
! 4220: ** respectively. A collating function must always return the same answer
! 4221: ** given the same inputs. If two or more collating functions are registered
! 4222: ** to the same collation name (using different eTextRep values) then all
! 4223: ** must give an equivalent answer when invoked with equivalent strings.
! 4224: ** The collating function must obey the following properties for all
! 4225: ** strings A, B, and C:
! 4226: **
! 4227: ** <ol>
! 4228: ** <li> If A==B then B==A.
! 4229: ** <li> If A==B and B==C then A==C.
! 4230: ** <li> If A<B THEN B>A.
! 4231: ** <li> If A<B and B<C then A<C.
! 4232: ** </ol>
! 4233: **
! 4234: ** If a collating function fails any of the above constraints and that
! 4235: ** collating function is registered and used, then the behavior of SQLite
! 4236: ** is undefined.
! 4237: **
! 4238: ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()
! 4239: ** with the addition that the xDestroy callback is invoked on pArg when
! 4240: ** the collating function is deleted.
! 4241: ** ^Collating functions are deleted when they are overridden by later
! 4242: ** calls to the collation creation functions or when the
! 4243: ** [database connection] is closed using [sqlite3_close()].
! 4244: **
! 4245: ** ^The xDestroy callback is <u>not</u> called if the
! 4246: ** sqlite3_create_collation_v2() function fails. Applications that invoke
! 4247: ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should
! 4248: ** check the return code and dispose of the application data pointer
! 4249: ** themselves rather than expecting SQLite to deal with it for them.
! 4250: ** This is different from every other SQLite interface. The inconsistency
! 4251: ** is unfortunate but cannot be changed without breaking backwards
! 4252: ** compatibility.
! 4253: **
! 4254: ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].
! 4255: */
! 4256: SQLITE_API int sqlite3_create_collation(
! 4257: sqlite3*,
! 4258: const char *zName,
! 4259: int eTextRep,
! 4260: void *pArg,
! 4261: int(*xCompare)(void*,int,const void*,int,const void*)
! 4262: );
! 4263: SQLITE_API int sqlite3_create_collation_v2(
! 4264: sqlite3*,
! 4265: const char *zName,
! 4266: int eTextRep,
! 4267: void *pArg,
! 4268: int(*xCompare)(void*,int,const void*,int,const void*),
! 4269: void(*xDestroy)(void*)
! 4270: );
! 4271: SQLITE_API int sqlite3_create_collation16(
! 4272: sqlite3*,
! 4273: const void *zName,
! 4274: int eTextRep,
! 4275: void *pArg,
! 4276: int(*xCompare)(void*,int,const void*,int,const void*)
! 4277: );
! 4278:
! 4279: /*
! 4280: ** CAPI3REF: Collation Needed Callbacks
! 4281: **
! 4282: ** ^To avoid having to register all collation sequences before a database
! 4283: ** can be used, a single callback function may be registered with the
! 4284: ** [database connection] to be invoked whenever an undefined collation
! 4285: ** sequence is required.
! 4286: **
! 4287: ** ^If the function is registered using the sqlite3_collation_needed() API,
! 4288: ** then it is passed the names of undefined collation sequences as strings
! 4289: ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,
! 4290: ** the names are passed as UTF-16 in machine native byte order.
! 4291: ** ^A call to either function replaces the existing collation-needed callback.
! 4292: **
! 4293: ** ^(When the callback is invoked, the first argument passed is a copy
! 4294: ** of the second argument to sqlite3_collation_needed() or
! 4295: ** sqlite3_collation_needed16(). The second argument is the database
! 4296: ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],
! 4297: ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation
! 4298: ** sequence function required. The fourth parameter is the name of the
! 4299: ** required collation sequence.)^
! 4300: **
! 4301: ** The callback function should register the desired collation using
! 4302: ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or
! 4303: ** [sqlite3_create_collation_v2()].
! 4304: */
! 4305: SQLITE_API int sqlite3_collation_needed(
! 4306: sqlite3*,
! 4307: void*,
! 4308: void(*)(void*,sqlite3*,int eTextRep,const char*)
! 4309: );
! 4310: SQLITE_API int sqlite3_collation_needed16(
! 4311: sqlite3*,
! 4312: void*,
! 4313: void(*)(void*,sqlite3*,int eTextRep,const void*)
! 4314: );
! 4315:
! 4316: #ifdef SQLITE_HAS_CODEC
! 4317: /*
! 4318: ** Specify the key for an encrypted database. This routine should be
! 4319: ** called right after sqlite3_open().
! 4320: **
! 4321: ** The code to implement this API is not available in the public release
! 4322: ** of SQLite.
! 4323: */
! 4324: SQLITE_API int sqlite3_key(
! 4325: sqlite3 *db, /* Database to be rekeyed */
! 4326: const void *pKey, int nKey /* The key */
! 4327: );
! 4328:
! 4329: /*
! 4330: ** Change the key on an open database. If the current database is not
! 4331: ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the
! 4332: ** database is decrypted.
! 4333: **
! 4334: ** The code to implement this API is not available in the public release
! 4335: ** of SQLite.
! 4336: */
! 4337: SQLITE_API int sqlite3_rekey(
! 4338: sqlite3 *db, /* Database to be rekeyed */
! 4339: const void *pKey, int nKey /* The new key */
! 4340: );
! 4341:
! 4342: /*
! 4343: ** Specify the activation key for a SEE database. Unless
! 4344: ** activated, none of the SEE routines will work.
! 4345: */
! 4346: SQLITE_API void sqlite3_activate_see(
! 4347: const char *zPassPhrase /* Activation phrase */
! 4348: );
! 4349: #endif
! 4350:
! 4351: #ifdef SQLITE_ENABLE_CEROD
! 4352: /*
! 4353: ** Specify the activation key for a CEROD database. Unless
! 4354: ** activated, none of the CEROD routines will work.
! 4355: */
! 4356: SQLITE_API void sqlite3_activate_cerod(
! 4357: const char *zPassPhrase /* Activation phrase */
! 4358: );
! 4359: #endif
! 4360:
! 4361: /*
! 4362: ** CAPI3REF: Suspend Execution For A Short Time
! 4363: **
! 4364: ** The sqlite3_sleep() function causes the current thread to suspend execution
! 4365: ** for at least a number of milliseconds specified in its parameter.
! 4366: **
! 4367: ** If the operating system does not support sleep requests with
! 4368: ** millisecond time resolution, then the time will be rounded up to
! 4369: ** the nearest second. The number of milliseconds of sleep actually
! 4370: ** requested from the operating system is returned.
! 4371: **
! 4372: ** ^SQLite implements this interface by calling the xSleep()
! 4373: ** method of the default [sqlite3_vfs] object. If the xSleep() method
! 4374: ** of the default VFS is not implemented correctly, or not implemented at
! 4375: ** all, then the behavior of sqlite3_sleep() may deviate from the description
! 4376: ** in the previous paragraphs.
! 4377: */
! 4378: SQLITE_API int sqlite3_sleep(int);
! 4379:
! 4380: /*
! 4381: ** CAPI3REF: Name Of The Folder Holding Temporary Files
! 4382: **
! 4383: ** ^(If this global variable is made to point to a string which is
! 4384: ** the name of a folder (a.k.a. directory), then all temporary files
! 4385: ** created by SQLite when using a built-in [sqlite3_vfs | VFS]
! 4386: ** will be placed in that directory.)^ ^If this variable
! 4387: ** is a NULL pointer, then SQLite performs a search for an appropriate
! 4388: ** temporary file directory.
! 4389: **
! 4390: ** It is not safe to read or modify this variable in more than one
! 4391: ** thread at a time. It is not safe to read or modify this variable
! 4392: ** if a [database connection] is being used at the same time in a separate
! 4393: ** thread.
! 4394: ** It is intended that this variable be set once
! 4395: ** as part of process initialization and before any SQLite interface
! 4396: ** routines have been called and that this variable remain unchanged
! 4397: ** thereafter.
! 4398: **
! 4399: ** ^The [temp_store_directory pragma] may modify this variable and cause
! 4400: ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,
! 4401: ** the [temp_store_directory pragma] always assumes that any string
! 4402: ** that this variable points to is held in memory obtained from
! 4403: ** [sqlite3_malloc] and the pragma may attempt to free that memory
! 4404: ** using [sqlite3_free].
! 4405: ** Hence, if this variable is modified directly, either it should be
! 4406: ** made NULL or made to point to memory obtained from [sqlite3_malloc]
! 4407: ** or else the use of the [temp_store_directory pragma] should be avoided.
! 4408: */
! 4409: SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
! 4410:
! 4411: /*
! 4412: ** CAPI3REF: Test For Auto-Commit Mode
! 4413: ** KEYWORDS: {autocommit mode}
! 4414: **
! 4415: ** ^The sqlite3_get_autocommit() interface returns non-zero or
! 4416: ** zero if the given database connection is or is not in autocommit mode,
! 4417: ** respectively. ^Autocommit mode is on by default.
! 4418: ** ^Autocommit mode is disabled by a [BEGIN] statement.
! 4419: ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].
! 4420: **
! 4421: ** If certain kinds of errors occur on a statement within a multi-statement
! 4422: ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],
! 4423: ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the
! 4424: ** transaction might be rolled back automatically. The only way to
! 4425: ** find out whether SQLite automatically rolled back the transaction after
! 4426: ** an error is to use this function.
! 4427: **
! 4428: ** If another thread changes the autocommit status of the database
! 4429: ** connection while this routine is running, then the return value
! 4430: ** is undefined.
! 4431: */
! 4432: SQLITE_API int sqlite3_get_autocommit(sqlite3*);
! 4433:
! 4434: /*
! 4435: ** CAPI3REF: Find The Database Handle Of A Prepared Statement
! 4436: **
! 4437: ** ^The sqlite3_db_handle interface returns the [database connection] handle
! 4438: ** to which a [prepared statement] belongs. ^The [database connection]
! 4439: ** returned by sqlite3_db_handle is the same [database connection]
! 4440: ** that was the first argument
! 4441: ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to
! 4442: ** create the statement in the first place.
! 4443: */
! 4444: SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*);
! 4445:
! 4446: /*
! 4447: ** CAPI3REF: Return The Filename For A Database Connection
! 4448: **
! 4449: ** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename
! 4450: ** associated with database N of connection D. ^The main database file
! 4451: ** has the name "main". If there is no attached database N on the database
! 4452: ** connection D, or if database N is a temporary or in-memory database, then
! 4453: ** a NULL pointer is returned.
! 4454: **
! 4455: ** ^The filename returned by this function is the output of the
! 4456: ** xFullPathname method of the [VFS]. ^In other words, the filename
! 4457: ** will be an absolute pathname, even if the filename used
! 4458: ** to open the database originally was a URI or relative pathname.
! 4459: */
! 4460: SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName);
! 4461:
! 4462: /*
! 4463: ** CAPI3REF: Find the next prepared statement
! 4464: **
! 4465: ** ^This interface returns a pointer to the next [prepared statement] after
! 4466: ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL
! 4467: ** then this interface returns a pointer to the first prepared statement
! 4468: ** associated with the database connection pDb. ^If no prepared statement
! 4469: ** satisfies the conditions of this routine, it returns NULL.
! 4470: **
! 4471: ** The [database connection] pointer D in a call to
! 4472: ** [sqlite3_next_stmt(D,S)] must refer to an open database
! 4473: ** connection and in particular must not be a NULL pointer.
! 4474: */
! 4475: SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt);
! 4476:
! 4477: /*
! 4478: ** CAPI3REF: Commit And Rollback Notification Callbacks
! 4479: **
! 4480: ** ^The sqlite3_commit_hook() interface registers a callback
! 4481: ** function to be invoked whenever a transaction is [COMMIT | committed].
! 4482: ** ^Any callback set by a previous call to sqlite3_commit_hook()
! 4483: ** for the same database connection is overridden.
! 4484: ** ^The sqlite3_rollback_hook() interface registers a callback
! 4485: ** function to be invoked whenever a transaction is [ROLLBACK | rolled back].
! 4486: ** ^Any callback set by a previous call to sqlite3_rollback_hook()
! 4487: ** for the same database connection is overridden.
! 4488: ** ^The pArg argument is passed through to the callback.
! 4489: ** ^If the callback on a commit hook function returns non-zero,
! 4490: ** then the commit is converted into a rollback.
! 4491: **
! 4492: ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions
! 4493: ** return the P argument from the previous call of the same function
! 4494: ** on the same [database connection] D, or NULL for
! 4495: ** the first call for each function on D.
! 4496: **
! 4497: ** The commit and rollback hook callbacks are not reentrant.
! 4498: ** The callback implementation must not do anything that will modify
! 4499: ** the database connection that invoked the callback. Any actions
! 4500: ** to modify the database connection must be deferred until after the
! 4501: ** completion of the [sqlite3_step()] call that triggered the commit
! 4502: ** or rollback hook in the first place.
! 4503: ** Note that running any other SQL statements, including SELECT statements,
! 4504: ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify
! 4505: ** the database connections for the meaning of "modify" in this paragraph.
! 4506: **
! 4507: ** ^Registering a NULL function disables the callback.
! 4508: **
! 4509: ** ^When the commit hook callback routine returns zero, the [COMMIT]
! 4510: ** operation is allowed to continue normally. ^If the commit hook
! 4511: ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].
! 4512: ** ^The rollback hook is invoked on a rollback that results from a commit
! 4513: ** hook returning non-zero, just as it would be with any other rollback.
! 4514: **
! 4515: ** ^For the purposes of this API, a transaction is said to have been
! 4516: ** rolled back if an explicit "ROLLBACK" statement is executed, or
! 4517: ** an error or constraint causes an implicit rollback to occur.
! 4518: ** ^The rollback callback is not invoked if a transaction is
! 4519: ** automatically rolled back because the database connection is closed.
! 4520: **
! 4521: ** See also the [sqlite3_update_hook()] interface.
! 4522: */
! 4523: SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*);
! 4524: SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*);
! 4525:
! 4526: /*
! 4527: ** CAPI3REF: Data Change Notification Callbacks
! 4528: **
! 4529: ** ^The sqlite3_update_hook() interface registers a callback function
! 4530: ** with the [database connection] identified by the first argument
! 4531: ** to be invoked whenever a row is updated, inserted or deleted.
! 4532: ** ^Any callback set by a previous call to this function
! 4533: ** for the same database connection is overridden.
! 4534: **
! 4535: ** ^The second argument is a pointer to the function to invoke when a
! 4536: ** row is updated, inserted or deleted.
! 4537: ** ^The first argument to the callback is a copy of the third argument
! 4538: ** to sqlite3_update_hook().
! 4539: ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],
! 4540: ** or [SQLITE_UPDATE], depending on the operation that caused the callback
! 4541: ** to be invoked.
! 4542: ** ^The third and fourth arguments to the callback contain pointers to the
! 4543: ** database and table name containing the affected row.
! 4544: ** ^The final callback parameter is the [rowid] of the row.
! 4545: ** ^In the case of an update, this is the [rowid] after the update takes place.
! 4546: **
! 4547: ** ^(The update hook is not invoked when internal system tables are
! 4548: ** modified (i.e. sqlite_master and sqlite_sequence).)^
! 4549: **
! 4550: ** ^In the current implementation, the update hook
! 4551: ** is not invoked when duplication rows are deleted because of an
! 4552: ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook
! 4553: ** invoked when rows are deleted using the [truncate optimization].
! 4554: ** The exceptions defined in this paragraph might change in a future
! 4555: ** release of SQLite.
! 4556: **
! 4557: ** The update hook implementation must not do anything that will modify
! 4558: ** the database connection that invoked the update hook. Any actions
! 4559: ** to modify the database connection must be deferred until after the
! 4560: ** completion of the [sqlite3_step()] call that triggered the update hook.
! 4561: ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their
! 4562: ** database connections for the meaning of "modify" in this paragraph.
! 4563: **
! 4564: ** ^The sqlite3_update_hook(D,C,P) function
! 4565: ** returns the P argument from the previous call
! 4566: ** on the same [database connection] D, or NULL for
! 4567: ** the first call on D.
! 4568: **
! 4569: ** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()]
! 4570: ** interfaces.
! 4571: */
! 4572: SQLITE_API void *sqlite3_update_hook(
! 4573: sqlite3*,
! 4574: void(*)(void *,int ,char const *,char const *,sqlite3_int64),
! 4575: void*
! 4576: );
! 4577:
! 4578: /*
! 4579: ** CAPI3REF: Enable Or Disable Shared Pager Cache
! 4580: ** KEYWORDS: {shared cache}
! 4581: **
! 4582: ** ^(This routine enables or disables the sharing of the database cache
! 4583: ** and schema data structures between [database connection | connections]
! 4584: ** to the same database. Sharing is enabled if the argument is true
! 4585: ** and disabled if the argument is false.)^
! 4586: **
! 4587: ** ^Cache sharing is enabled and disabled for an entire process.
! 4588: ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite,
! 4589: ** sharing was enabled or disabled for each thread separately.
! 4590: **
! 4591: ** ^(The cache sharing mode set by this interface effects all subsequent
! 4592: ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].
! 4593: ** Existing database connections continue use the sharing mode
! 4594: ** that was in effect at the time they were opened.)^
! 4595: **
! 4596: ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled
! 4597: ** successfully. An [error code] is returned otherwise.)^
! 4598: **
! 4599: ** ^Shared cache is disabled by default. But this might change in
! 4600: ** future releases of SQLite. Applications that care about shared
! 4601: ** cache setting should set it explicitly.
! 4602: **
! 4603: ** See Also: [SQLite Shared-Cache Mode]
! 4604: */
! 4605: SQLITE_API int sqlite3_enable_shared_cache(int);
! 4606:
! 4607: /*
! 4608: ** CAPI3REF: Attempt To Free Heap Memory
! 4609: **
! 4610: ** ^The sqlite3_release_memory() interface attempts to free N bytes
! 4611: ** of heap memory by deallocating non-essential memory allocations
! 4612: ** held by the database library. Memory used to cache database
! 4613: ** pages to improve performance is an example of non-essential memory.
! 4614: ** ^sqlite3_release_memory() returns the number of bytes actually freed,
! 4615: ** which might be more or less than the amount requested.
! 4616: ** ^The sqlite3_release_memory() routine is a no-op returning zero
! 4617: ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].
! 4618: **
! 4619: ** See also: [sqlite3_db_release_memory()]
! 4620: */
! 4621: SQLITE_API int sqlite3_release_memory(int);
! 4622:
! 4623: /*
! 4624: ** CAPI3REF: Free Memory Used By A Database Connection
! 4625: **
! 4626: ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap
! 4627: ** memory as possible from database connection D. Unlike the
! 4628: ** [sqlite3_release_memory()] interface, this interface is effect even
! 4629: ** when then [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is
! 4630: ** omitted.
! 4631: **
! 4632: ** See also: [sqlite3_release_memory()]
! 4633: */
! 4634: SQLITE_API int sqlite3_db_release_memory(sqlite3*);
! 4635:
! 4636: /*
! 4637: ** CAPI3REF: Impose A Limit On Heap Size
! 4638: **
! 4639: ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the
! 4640: ** soft limit on the amount of heap memory that may be allocated by SQLite.
! 4641: ** ^SQLite strives to keep heap memory utilization below the soft heap
! 4642: ** limit by reducing the number of pages held in the page cache
! 4643: ** as heap memory usages approaches the limit.
! 4644: ** ^The soft heap limit is "soft" because even though SQLite strives to stay
! 4645: ** below the limit, it will exceed the limit rather than generate
! 4646: ** an [SQLITE_NOMEM] error. In other words, the soft heap limit
! 4647: ** is advisory only.
! 4648: **
! 4649: ** ^The return value from sqlite3_soft_heap_limit64() is the size of
! 4650: ** the soft heap limit prior to the call, or negative in the case of an
! 4651: ** error. ^If the argument N is negative
! 4652: ** then no change is made to the soft heap limit. Hence, the current
! 4653: ** size of the soft heap limit can be determined by invoking
! 4654: ** sqlite3_soft_heap_limit64() with a negative argument.
! 4655: **
! 4656: ** ^If the argument N is zero then the soft heap limit is disabled.
! 4657: **
! 4658: ** ^(The soft heap limit is not enforced in the current implementation
! 4659: ** if one or more of following conditions are true:
! 4660: **
! 4661: ** <ul>
! 4662: ** <li> The soft heap limit is set to zero.
! 4663: ** <li> Memory accounting is disabled using a combination of the
! 4664: ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and
! 4665: ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.
! 4666: ** <li> An alternative page cache implementation is specified using
! 4667: ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).
! 4668: ** <li> The page cache allocates from its own memory pool supplied
! 4669: ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than
! 4670: ** from the heap.
! 4671: ** </ul>)^
! 4672: **
! 4673: ** Beginning with SQLite version 3.7.3, the soft heap limit is enforced
! 4674: ** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]
! 4675: ** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],
! 4676: ** the soft heap limit is enforced on every memory allocation. Without
! 4677: ** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced
! 4678: ** when memory is allocated by the page cache. Testing suggests that because
! 4679: ** the page cache is the predominate memory user in SQLite, most
! 4680: ** applications will achieve adequate soft heap limit enforcement without
! 4681: ** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].
! 4682: **
! 4683: ** The circumstances under which SQLite will enforce the soft heap limit may
! 4684: ** changes in future releases of SQLite.
! 4685: */
! 4686: SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N);
! 4687:
! 4688: /*
! 4689: ** CAPI3REF: Deprecated Soft Heap Limit Interface
! 4690: ** DEPRECATED
! 4691: **
! 4692: ** This is a deprecated version of the [sqlite3_soft_heap_limit64()]
! 4693: ** interface. This routine is provided for historical compatibility
! 4694: ** only. All new applications should use the
! 4695: ** [sqlite3_soft_heap_limit64()] interface rather than this one.
! 4696: */
! 4697: SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N);
! 4698:
! 4699:
! 4700: /*
! 4701: ** CAPI3REF: Extract Metadata About A Column Of A Table
! 4702: **
! 4703: ** ^This routine returns metadata about a specific column of a specific
! 4704: ** database table accessible using the [database connection] handle
! 4705: ** passed as the first function argument.
! 4706: **
! 4707: ** ^The column is identified by the second, third and fourth parameters to
! 4708: ** this function. ^The second parameter is either the name of the database
! 4709: ** (i.e. "main", "temp", or an attached database) containing the specified
! 4710: ** table or NULL. ^If it is NULL, then all attached databases are searched
! 4711: ** for the table using the same algorithm used by the database engine to
! 4712: ** resolve unqualified table references.
! 4713: **
! 4714: ** ^The third and fourth parameters to this function are the table and column
! 4715: ** name of the desired column, respectively. Neither of these parameters
! 4716: ** may be NULL.
! 4717: **
! 4718: ** ^Metadata is returned by writing to the memory locations passed as the 5th
! 4719: ** and subsequent parameters to this function. ^Any of these arguments may be
! 4720: ** NULL, in which case the corresponding element of metadata is omitted.
! 4721: **
! 4722: ** ^(<blockquote>
! 4723: ** <table border="1">
! 4724: ** <tr><th> Parameter <th> Output<br>Type <th> Description
! 4725: **
! 4726: ** <tr><td> 5th <td> const char* <td> Data type
! 4727: ** <tr><td> 6th <td> const char* <td> Name of default collation sequence
! 4728: ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint
! 4729: ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY
! 4730: ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]
! 4731: ** </table>
! 4732: ** </blockquote>)^
! 4733: **
! 4734: ** ^The memory pointed to by the character pointers returned for the
! 4735: ** declaration type and collation sequence is valid only until the next
! 4736: ** call to any SQLite API function.
! 4737: **
! 4738: ** ^If the specified table is actually a view, an [error code] is returned.
! 4739: **
! 4740: ** ^If the specified column is "rowid", "oid" or "_rowid_" and an
! 4741: ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output
! 4742: ** parameters are set for the explicitly declared column. ^(If there is no
! 4743: ** explicitly declared [INTEGER PRIMARY KEY] column, then the output
! 4744: ** parameters are set as follows:
! 4745: **
! 4746: ** <pre>
! 4747: ** data type: "INTEGER"
! 4748: ** collation sequence: "BINARY"
! 4749: ** not null: 0
! 4750: ** primary key: 1
! 4751: ** auto increment: 0
! 4752: ** </pre>)^
! 4753: **
! 4754: ** ^(This function may load one or more schemas from database files. If an
! 4755: ** error occurs during this process, or if the requested table or column
! 4756: ** cannot be found, an [error code] is returned and an error message left
! 4757: ** in the [database connection] (to be retrieved using sqlite3_errmsg()).)^
! 4758: **
! 4759: ** ^This API is only available if the library was compiled with the
! 4760: ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined.
! 4761: */
! 4762: SQLITE_API int sqlite3_table_column_metadata(
! 4763: sqlite3 *db, /* Connection handle */
! 4764: const char *zDbName, /* Database name or NULL */
! 4765: const char *zTableName, /* Table name */
! 4766: const char *zColumnName, /* Column name */
! 4767: char const **pzDataType, /* OUTPUT: Declared data type */
! 4768: char const **pzCollSeq, /* OUTPUT: Collation sequence name */
! 4769: int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */
! 4770: int *pPrimaryKey, /* OUTPUT: True if column part of PK */
! 4771: int *pAutoinc /* OUTPUT: True if column is auto-increment */
! 4772: );
! 4773:
! 4774: /*
! 4775: ** CAPI3REF: Load An Extension
! 4776: **
! 4777: ** ^This interface loads an SQLite extension library from the named file.
! 4778: **
! 4779: ** ^The sqlite3_load_extension() interface attempts to load an
! 4780: ** SQLite extension library contained in the file zFile.
! 4781: **
! 4782: ** ^The entry point is zProc.
! 4783: ** ^zProc may be 0, in which case the name of the entry point
! 4784: ** defaults to "sqlite3_extension_init".
! 4785: ** ^The sqlite3_load_extension() interface returns
! 4786: ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
! 4787: ** ^If an error occurs and pzErrMsg is not 0, then the
! 4788: ** [sqlite3_load_extension()] interface shall attempt to
! 4789: ** fill *pzErrMsg with error message text stored in memory
! 4790: ** obtained from [sqlite3_malloc()]. The calling function
! 4791: ** should free this memory by calling [sqlite3_free()].
! 4792: **
! 4793: ** ^Extension loading must be enabled using
! 4794: ** [sqlite3_enable_load_extension()] prior to calling this API,
! 4795: ** otherwise an error will be returned.
! 4796: **
! 4797: ** See also the [load_extension() SQL function].
! 4798: */
! 4799: SQLITE_API int sqlite3_load_extension(
! 4800: sqlite3 *db, /* Load the extension into this database connection */
! 4801: const char *zFile, /* Name of the shared library containing extension */
! 4802: const char *zProc, /* Entry point. Derived from zFile if 0 */
! 4803: char **pzErrMsg /* Put error message here if not 0 */
! 4804: );
! 4805:
! 4806: /*
! 4807: ** CAPI3REF: Enable Or Disable Extension Loading
! 4808: **
! 4809: ** ^So as not to open security holes in older applications that are
! 4810: ** unprepared to deal with extension loading, and as a means of disabling
! 4811: ** extension loading while evaluating user-entered SQL, the following API
! 4812: ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
! 4813: **
! 4814: ** ^Extension loading is off by default. See ticket #1863.
! 4815: ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
! 4816: ** to turn extension loading on and call it with onoff==0 to turn
! 4817: ** it back off again.
! 4818: */
! 4819: SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
! 4820:
! 4821: /*
! 4822: ** CAPI3REF: Automatically Load Statically Linked Extensions
! 4823: **
! 4824: ** ^This interface causes the xEntryPoint() function to be invoked for
! 4825: ** each new [database connection] that is created. The idea here is that
! 4826: ** xEntryPoint() is the entry point for a statically linked SQLite extension
! 4827: ** that is to be automatically loaded into all new database connections.
! 4828: **
! 4829: ** ^(Even though the function prototype shows that xEntryPoint() takes
! 4830: ** no arguments and returns void, SQLite invokes xEntryPoint() with three
! 4831: ** arguments and expects and integer result as if the signature of the
! 4832: ** entry point where as follows:
! 4833: **
! 4834: ** <blockquote><pre>
! 4835: ** int xEntryPoint(
! 4836: ** sqlite3 *db,
! 4837: ** const char **pzErrMsg,
! 4838: ** const struct sqlite3_api_routines *pThunk
! 4839: ** );
! 4840: ** </pre></blockquote>)^
! 4841: **
! 4842: ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg
! 4843: ** point to an appropriate error message (obtained from [sqlite3_mprintf()])
! 4844: ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg
! 4845: ** is NULL before calling the xEntryPoint(). ^SQLite will invoke
! 4846: ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any
! 4847: ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],
! 4848: ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.
! 4849: **
! 4850: ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already
! 4851: ** on the list of automatic extensions is a harmless no-op. ^No entry point
! 4852: ** will be called more than once for each database connection that is opened.
! 4853: **
! 4854: ** See also: [sqlite3_reset_auto_extension()].
! 4855: */
! 4856: SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
! 4857:
! 4858: /*
! 4859: ** CAPI3REF: Reset Automatic Extension Loading
! 4860: **
! 4861: ** ^This interface disables all automatic extensions previously
! 4862: ** registered using [sqlite3_auto_extension()].
! 4863: */
! 4864: SQLITE_API void sqlite3_reset_auto_extension(void);
! 4865:
! 4866: /*
! 4867: ** The interface to the virtual-table mechanism is currently considered
! 4868: ** to be experimental. The interface might change in incompatible ways.
! 4869: ** If this is a problem for you, do not use the interface at this time.
! 4870: **
! 4871: ** When the virtual-table mechanism stabilizes, we will declare the
! 4872: ** interface fixed, support it indefinitely, and remove this comment.
! 4873: */
! 4874:
! 4875: /*
! 4876: ** Structures used by the virtual table interface
! 4877: */
! 4878: typedef struct sqlite3_vtab sqlite3_vtab;
! 4879: typedef struct sqlite3_index_info sqlite3_index_info;
! 4880: typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
! 4881: typedef struct sqlite3_module sqlite3_module;
! 4882:
! 4883: /*
! 4884: ** CAPI3REF: Virtual Table Object
! 4885: ** KEYWORDS: sqlite3_module {virtual table module}
! 4886: **
! 4887: ** This structure, sometimes called a "virtual table module",
! 4888: ** defines the implementation of a [virtual tables].
! 4889: ** This structure consists mostly of methods for the module.
! 4890: **
! 4891: ** ^A virtual table module is created by filling in a persistent
! 4892: ** instance of this structure and passing a pointer to that instance
! 4893: ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].
! 4894: ** ^The registration remains valid until it is replaced by a different
! 4895: ** module or until the [database connection] closes. The content
! 4896: ** of this structure must not change while it is registered with
! 4897: ** any database connection.
! 4898: */
! 4899: struct sqlite3_module {
! 4900: int iVersion;
! 4901: int (*xCreate)(sqlite3*, void *pAux,
! 4902: int argc, const char *const*argv,
! 4903: sqlite3_vtab **ppVTab, char**);
! 4904: int (*xConnect)(sqlite3*, void *pAux,
! 4905: int argc, const char *const*argv,
! 4906: sqlite3_vtab **ppVTab, char**);
! 4907: int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
! 4908: int (*xDisconnect)(sqlite3_vtab *pVTab);
! 4909: int (*xDestroy)(sqlite3_vtab *pVTab);
! 4910: int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
! 4911: int (*xClose)(sqlite3_vtab_cursor*);
! 4912: int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
! 4913: int argc, sqlite3_value **argv);
! 4914: int (*xNext)(sqlite3_vtab_cursor*);
! 4915: int (*xEof)(sqlite3_vtab_cursor*);
! 4916: int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
! 4917: int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
! 4918: int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
! 4919: int (*xBegin)(sqlite3_vtab *pVTab);
! 4920: int (*xSync)(sqlite3_vtab *pVTab);
! 4921: int (*xCommit)(sqlite3_vtab *pVTab);
! 4922: int (*xRollback)(sqlite3_vtab *pVTab);
! 4923: int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
! 4924: void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
! 4925: void **ppArg);
! 4926: int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
! 4927: /* The methods above are in version 1 of the sqlite_module object. Those
! 4928: ** below are for version 2 and greater. */
! 4929: int (*xSavepoint)(sqlite3_vtab *pVTab, int);
! 4930: int (*xRelease)(sqlite3_vtab *pVTab, int);
! 4931: int (*xRollbackTo)(sqlite3_vtab *pVTab, int);
! 4932: };
! 4933:
! 4934: /*
! 4935: ** CAPI3REF: Virtual Table Indexing Information
! 4936: ** KEYWORDS: sqlite3_index_info
! 4937: **
! 4938: ** The sqlite3_index_info structure and its substructures is used as part
! 4939: ** of the [virtual table] interface to
! 4940: ** pass information into and receive the reply from the [xBestIndex]
! 4941: ** method of a [virtual table module]. The fields under **Inputs** are the
! 4942: ** inputs to xBestIndex and are read-only. xBestIndex inserts its
! 4943: ** results into the **Outputs** fields.
! 4944: **
! 4945: ** ^(The aConstraint[] array records WHERE clause constraints of the form:
! 4946: **
! 4947: ** <blockquote>column OP expr</blockquote>
! 4948: **
! 4949: ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is
! 4950: ** stored in aConstraint[].op using one of the
! 4951: ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^
! 4952: ** ^(The index of the column is stored in
! 4953: ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the
! 4954: ** expr on the right-hand side can be evaluated (and thus the constraint
! 4955: ** is usable) and false if it cannot.)^
! 4956: **
! 4957: ** ^The optimizer automatically inverts terms of the form "expr OP column"
! 4958: ** and makes other simplifications to the WHERE clause in an attempt to
! 4959: ** get as many WHERE clause terms into the form shown above as possible.
! 4960: ** ^The aConstraint[] array only reports WHERE clause terms that are
! 4961: ** relevant to the particular virtual table being queried.
! 4962: **
! 4963: ** ^Information about the ORDER BY clause is stored in aOrderBy[].
! 4964: ** ^Each term of aOrderBy records a column of the ORDER BY clause.
! 4965: **
! 4966: ** The [xBestIndex] method must fill aConstraintUsage[] with information
! 4967: ** about what parameters to pass to xFilter. ^If argvIndex>0 then
! 4968: ** the right-hand side of the corresponding aConstraint[] is evaluated
! 4969: ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit
! 4970: ** is true, then the constraint is assumed to be fully handled by the
! 4971: ** virtual table and is not checked again by SQLite.)^
! 4972: **
! 4973: ** ^The idxNum and idxPtr values are recorded and passed into the
! 4974: ** [xFilter] method.
! 4975: ** ^[sqlite3_free()] is used to free idxPtr if and only if
! 4976: ** needToFreeIdxPtr is true.
! 4977: **
! 4978: ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in
! 4979: ** the correct order to satisfy the ORDER BY clause so that no separate
! 4980: ** sorting step is required.
! 4981: **
! 4982: ** ^The estimatedCost value is an estimate of the cost of doing the
! 4983: ** particular lookup. A full scan of a table with N entries should have
! 4984: ** a cost of N. A binary search of a table of N entries should have a
! 4985: ** cost of approximately log(N).
! 4986: */
! 4987: struct sqlite3_index_info {
! 4988: /* Inputs */
! 4989: int nConstraint; /* Number of entries in aConstraint */
! 4990: struct sqlite3_index_constraint {
! 4991: int iColumn; /* Column on left-hand side of constraint */
! 4992: unsigned char op; /* Constraint operator */
! 4993: unsigned char usable; /* True if this constraint is usable */
! 4994: int iTermOffset; /* Used internally - xBestIndex should ignore */
! 4995: } *aConstraint; /* Table of WHERE clause constraints */
! 4996: int nOrderBy; /* Number of terms in the ORDER BY clause */
! 4997: struct sqlite3_index_orderby {
! 4998: int iColumn; /* Column number */
! 4999: unsigned char desc; /* True for DESC. False for ASC. */
! 5000: } *aOrderBy; /* The ORDER BY clause */
! 5001: /* Outputs */
! 5002: struct sqlite3_index_constraint_usage {
! 5003: int argvIndex; /* if >0, constraint is part of argv to xFilter */
! 5004: unsigned char omit; /* Do not code a test for this constraint */
! 5005: } *aConstraintUsage;
! 5006: int idxNum; /* Number used to identify the index */
! 5007: char *idxStr; /* String, possibly obtained from sqlite3_malloc */
! 5008: int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */
! 5009: int orderByConsumed; /* True if output is already ordered */
! 5010: double estimatedCost; /* Estimated cost of using this index */
! 5011: };
! 5012:
! 5013: /*
! 5014: ** CAPI3REF: Virtual Table Constraint Operator Codes
! 5015: **
! 5016: ** These macros defined the allowed values for the
! 5017: ** [sqlite3_index_info].aConstraint[].op field. Each value represents
! 5018: ** an operator that is part of a constraint term in the wHERE clause of
! 5019: ** a query that uses a [virtual table].
! 5020: */
! 5021: #define SQLITE_INDEX_CONSTRAINT_EQ 2
! 5022: #define SQLITE_INDEX_CONSTRAINT_GT 4
! 5023: #define SQLITE_INDEX_CONSTRAINT_LE 8
! 5024: #define SQLITE_INDEX_CONSTRAINT_LT 16
! 5025: #define SQLITE_INDEX_CONSTRAINT_GE 32
! 5026: #define SQLITE_INDEX_CONSTRAINT_MATCH 64
! 5027:
! 5028: /*
! 5029: ** CAPI3REF: Register A Virtual Table Implementation
! 5030: **
! 5031: ** ^These routines are used to register a new [virtual table module] name.
! 5032: ** ^Module names must be registered before
! 5033: ** creating a new [virtual table] using the module and before using a
! 5034: ** preexisting [virtual table] for the module.
! 5035: **
! 5036: ** ^The module name is registered on the [database connection] specified
! 5037: ** by the first parameter. ^The name of the module is given by the
! 5038: ** second parameter. ^The third parameter is a pointer to
! 5039: ** the implementation of the [virtual table module]. ^The fourth
! 5040: ** parameter is an arbitrary client data pointer that is passed through
! 5041: ** into the [xCreate] and [xConnect] methods of the virtual table module
! 5042: ** when a new virtual table is be being created or reinitialized.
! 5043: **
! 5044: ** ^The sqlite3_create_module_v2() interface has a fifth parameter which
! 5045: ** is a pointer to a destructor for the pClientData. ^SQLite will
! 5046: ** invoke the destructor function (if it is not NULL) when SQLite
! 5047: ** no longer needs the pClientData pointer. ^The destructor will also
! 5048: ** be invoked if the call to sqlite3_create_module_v2() fails.
! 5049: ** ^The sqlite3_create_module()
! 5050: ** interface is equivalent to sqlite3_create_module_v2() with a NULL
! 5051: ** destructor.
! 5052: */
! 5053: SQLITE_API int sqlite3_create_module(
! 5054: sqlite3 *db, /* SQLite connection to register module with */
! 5055: const char *zName, /* Name of the module */
! 5056: const sqlite3_module *p, /* Methods for the module */
! 5057: void *pClientData /* Client data for xCreate/xConnect */
! 5058: );
! 5059: SQLITE_API int sqlite3_create_module_v2(
! 5060: sqlite3 *db, /* SQLite connection to register module with */
! 5061: const char *zName, /* Name of the module */
! 5062: const sqlite3_module *p, /* Methods for the module */
! 5063: void *pClientData, /* Client data for xCreate/xConnect */
! 5064: void(*xDestroy)(void*) /* Module destructor function */
! 5065: );
! 5066:
! 5067: /*
! 5068: ** CAPI3REF: Virtual Table Instance Object
! 5069: ** KEYWORDS: sqlite3_vtab
! 5070: **
! 5071: ** Every [virtual table module] implementation uses a subclass
! 5072: ** of this object to describe a particular instance
! 5073: ** of the [virtual table]. Each subclass will
! 5074: ** be tailored to the specific needs of the module implementation.
! 5075: ** The purpose of this superclass is to define certain fields that are
! 5076: ** common to all module implementations.
! 5077: **
! 5078: ** ^Virtual tables methods can set an error message by assigning a
! 5079: ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
! 5080: ** take care that any prior string is freed by a call to [sqlite3_free()]
! 5081: ** prior to assigning a new string to zErrMsg. ^After the error message
! 5082: ** is delivered up to the client application, the string will be automatically
! 5083: ** freed by sqlite3_free() and the zErrMsg field will be zeroed.
! 5084: */
! 5085: struct sqlite3_vtab {
! 5086: const sqlite3_module *pModule; /* The module for this virtual table */
! 5087: int nRef; /* NO LONGER USED */
! 5088: char *zErrMsg; /* Error message from sqlite3_mprintf() */
! 5089: /* Virtual table implementations will typically add additional fields */
! 5090: };
! 5091:
! 5092: /*
! 5093: ** CAPI3REF: Virtual Table Cursor Object
! 5094: ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
! 5095: **
! 5096: ** Every [virtual table module] implementation uses a subclass of the
! 5097: ** following structure to describe cursors that point into the
! 5098: ** [virtual table] and are used
! 5099: ** to loop through the virtual table. Cursors are created using the
! 5100: ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
! 5101: ** by the [sqlite3_module.xClose | xClose] method. Cursors are used
! 5102: ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
! 5103: ** of the module. Each module implementation will define
! 5104: ** the content of a cursor structure to suit its own needs.
! 5105: **
! 5106: ** This superclass exists in order to define fields of the cursor that
! 5107: ** are common to all implementations.
! 5108: */
! 5109: struct sqlite3_vtab_cursor {
! 5110: sqlite3_vtab *pVtab; /* Virtual table of this cursor */
! 5111: /* Virtual table implementations will typically add additional fields */
! 5112: };
! 5113:
! 5114: /*
! 5115: ** CAPI3REF: Declare The Schema Of A Virtual Table
! 5116: **
! 5117: ** ^The [xCreate] and [xConnect] methods of a
! 5118: ** [virtual table module] call this interface
! 5119: ** to declare the format (the names and datatypes of the columns) of
! 5120: ** the virtual tables they implement.
! 5121: */
! 5122: SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL);
! 5123:
! 5124: /*
! 5125: ** CAPI3REF: Overload A Function For A Virtual Table
! 5126: **
! 5127: ** ^(Virtual tables can provide alternative implementations of functions
! 5128: ** using the [xFindFunction] method of the [virtual table module].
! 5129: ** But global versions of those functions
! 5130: ** must exist in order to be overloaded.)^
! 5131: **
! 5132: ** ^(This API makes sure a global version of a function with a particular
! 5133: ** name and number of parameters exists. If no such function exists
! 5134: ** before this API is called, a new function is created.)^ ^The implementation
! 5135: ** of the new function always causes an exception to be thrown. So
! 5136: ** the new function is not good for anything by itself. Its only
! 5137: ** purpose is to be a placeholder function that can be overloaded
! 5138: ** by a [virtual table].
! 5139: */
! 5140: SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
! 5141:
! 5142: /*
! 5143: ** The interface to the virtual-table mechanism defined above (back up
! 5144: ** to a comment remarkably similar to this one) is currently considered
! 5145: ** to be experimental. The interface might change in incompatible ways.
! 5146: ** If this is a problem for you, do not use the interface at this time.
! 5147: **
! 5148: ** When the virtual-table mechanism stabilizes, we will declare the
! 5149: ** interface fixed, support it indefinitely, and remove this comment.
! 5150: */
! 5151:
! 5152: /*
! 5153: ** CAPI3REF: A Handle To An Open BLOB
! 5154: ** KEYWORDS: {BLOB handle} {BLOB handles}
! 5155: **
! 5156: ** An instance of this object represents an open BLOB on which
! 5157: ** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
! 5158: ** ^Objects of this type are created by [sqlite3_blob_open()]
! 5159: ** and destroyed by [sqlite3_blob_close()].
! 5160: ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
! 5161: ** can be used to read or write small subsections of the BLOB.
! 5162: ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
! 5163: */
! 5164: typedef struct sqlite3_blob sqlite3_blob;
! 5165:
! 5166: /*
! 5167: ** CAPI3REF: Open A BLOB For Incremental I/O
! 5168: **
! 5169: ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located
! 5170: ** in row iRow, column zColumn, table zTable in database zDb;
! 5171: ** in other words, the same BLOB that would be selected by:
! 5172: **
! 5173: ** <pre>
! 5174: ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
! 5175: ** </pre>)^
! 5176: **
! 5177: ** ^If the flags parameter is non-zero, then the BLOB is opened for read
! 5178: ** and write access. ^If it is zero, the BLOB is opened for read access.
! 5179: ** ^It is not possible to open a column that is part of an index or primary
! 5180: ** key for writing. ^If [foreign key constraints] are enabled, it is
! 5181: ** not possible to open a column that is part of a [child key] for writing.
! 5182: **
! 5183: ** ^Note that the database name is not the filename that contains
! 5184: ** the database but rather the symbolic name of the database that
! 5185: ** appears after the AS keyword when the database is connected using [ATTACH].
! 5186: ** ^For the main database file, the database name is "main".
! 5187: ** ^For TEMP tables, the database name is "temp".
! 5188: **
! 5189: ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is written
! 5190: ** to *ppBlob. Otherwise an [error code] is returned and *ppBlob is set
! 5191: ** to be a null pointer.)^
! 5192: ** ^This function sets the [database connection] error code and message
! 5193: ** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()] and related
! 5194: ** functions. ^Note that the *ppBlob variable is always initialized in a
! 5195: ** way that makes it safe to invoke [sqlite3_blob_close()] on *ppBlob
! 5196: ** regardless of the success or failure of this routine.
! 5197: **
! 5198: ** ^(If the row that a BLOB handle points to is modified by an
! 5199: ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects
! 5200: ** then the BLOB handle is marked as "expired".
! 5201: ** This is true if any column of the row is changed, even a column
! 5202: ** other than the one the BLOB handle is open on.)^
! 5203: ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for
! 5204: ** an expired BLOB handle fail with a return code of [SQLITE_ABORT].
! 5205: ** ^(Changes written into a BLOB prior to the BLOB expiring are not
! 5206: ** rolled back by the expiration of the BLOB. Such changes will eventually
! 5207: ** commit if the transaction continues to completion.)^
! 5208: **
! 5209: ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of
! 5210: ** the opened blob. ^The size of a blob may not be changed by this
! 5211: ** interface. Use the [UPDATE] SQL command to change the size of a
! 5212: ** blob.
! 5213: **
! 5214: ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces
! 5215: ** and the built-in [zeroblob] SQL function can be used, if desired,
! 5216: ** to create an empty, zero-filled blob in which to read or write using
! 5217: ** this interface.
! 5218: **
! 5219: ** To avoid a resource leak, every open [BLOB handle] should eventually
! 5220: ** be released by a call to [sqlite3_blob_close()].
! 5221: */
! 5222: SQLITE_API int sqlite3_blob_open(
! 5223: sqlite3*,
! 5224: const char *zDb,
! 5225: const char *zTable,
! 5226: const char *zColumn,
! 5227: sqlite3_int64 iRow,
! 5228: int flags,
! 5229: sqlite3_blob **ppBlob
! 5230: );
! 5231:
! 5232: /*
! 5233: ** CAPI3REF: Move a BLOB Handle to a New Row
! 5234: **
! 5235: ** ^This function is used to move an existing blob handle so that it points
! 5236: ** to a different row of the same database table. ^The new row is identified
! 5237: ** by the rowid value passed as the second argument. Only the row can be
! 5238: ** changed. ^The database, table and column on which the blob handle is open
! 5239: ** remain the same. Moving an existing blob handle to a new row can be
! 5240: ** faster than closing the existing handle and opening a new one.
! 5241: **
! 5242: ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -
! 5243: ** it must exist and there must be either a blob or text value stored in
! 5244: ** the nominated column.)^ ^If the new row is not present in the table, or if
! 5245: ** it does not contain a blob or text value, or if another error occurs, an
! 5246: ** SQLite error code is returned and the blob handle is considered aborted.
! 5247: ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or
! 5248: ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return
! 5249: ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle
! 5250: ** always returns zero.
! 5251: **
! 5252: ** ^This function sets the database handle error code and message.
! 5253: */
! 5254: SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64);
! 5255:
! 5256: /*
! 5257: ** CAPI3REF: Close A BLOB Handle
! 5258: **
! 5259: ** ^Closes an open [BLOB handle].
! 5260: **
! 5261: ** ^Closing a BLOB shall cause the current transaction to commit
! 5262: ** if there are no other BLOBs, no pending prepared statements, and the
! 5263: ** database connection is in [autocommit mode].
! 5264: ** ^If any writes were made to the BLOB, they might be held in cache
! 5265: ** until the close operation if they will fit.
! 5266: **
! 5267: ** ^(Closing the BLOB often forces the changes
! 5268: ** out to disk and so if any I/O errors occur, they will likely occur
! 5269: ** at the time when the BLOB is closed. Any errors that occur during
! 5270: ** closing are reported as a non-zero return value.)^
! 5271: **
! 5272: ** ^(The BLOB is closed unconditionally. Even if this routine returns
! 5273: ** an error code, the BLOB is still closed.)^
! 5274: **
! 5275: ** ^Calling this routine with a null pointer (such as would be returned
! 5276: ** by a failed call to [sqlite3_blob_open()]) is a harmless no-op.
! 5277: */
! 5278: SQLITE_API int sqlite3_blob_close(sqlite3_blob *);
! 5279:
! 5280: /*
! 5281: ** CAPI3REF: Return The Size Of An Open BLOB
! 5282: **
! 5283: ** ^Returns the size in bytes of the BLOB accessible via the
! 5284: ** successfully opened [BLOB handle] in its only argument. ^The
! 5285: ** incremental blob I/O routines can only read or overwriting existing
! 5286: ** blob content; they cannot change the size of a blob.
! 5287: **
! 5288: ** This routine only works on a [BLOB handle] which has been created
! 5289: ** by a prior successful call to [sqlite3_blob_open()] and which has not
! 5290: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
! 5291: ** to this routine results in undefined and probably undesirable behavior.
! 5292: */
! 5293: SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *);
! 5294:
! 5295: /*
! 5296: ** CAPI3REF: Read Data From A BLOB Incrementally
! 5297: **
! 5298: ** ^(This function is used to read data from an open [BLOB handle] into a
! 5299: ** caller-supplied buffer. N bytes of data are copied into buffer Z
! 5300: ** from the open BLOB, starting at offset iOffset.)^
! 5301: **
! 5302: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
! 5303: ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is
! 5304: ** less than zero, [SQLITE_ERROR] is returned and no data is read.
! 5305: ** ^The size of the blob (and hence the maximum value of N+iOffset)
! 5306: ** can be determined using the [sqlite3_blob_bytes()] interface.
! 5307: **
! 5308: ** ^An attempt to read from an expired [BLOB handle] fails with an
! 5309: ** error code of [SQLITE_ABORT].
! 5310: **
! 5311: ** ^(On success, sqlite3_blob_read() returns SQLITE_OK.
! 5312: ** Otherwise, an [error code] or an [extended error code] is returned.)^
! 5313: **
! 5314: ** This routine only works on a [BLOB handle] which has been created
! 5315: ** by a prior successful call to [sqlite3_blob_open()] and which has not
! 5316: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
! 5317: ** to this routine results in undefined and probably undesirable behavior.
! 5318: **
! 5319: ** See also: [sqlite3_blob_write()].
! 5320: */
! 5321: SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset);
! 5322:
! 5323: /*
! 5324: ** CAPI3REF: Write Data Into A BLOB Incrementally
! 5325: **
! 5326: ** ^This function is used to write data into an open [BLOB handle] from a
! 5327: ** caller-supplied buffer. ^N bytes of data are copied from the buffer Z
! 5328: ** into the open BLOB, starting at offset iOffset.
! 5329: **
! 5330: ** ^If the [BLOB handle] passed as the first argument was not opened for
! 5331: ** writing (the flags parameter to [sqlite3_blob_open()] was zero),
! 5332: ** this function returns [SQLITE_READONLY].
! 5333: **
! 5334: ** ^This function may only modify the contents of the BLOB; it is
! 5335: ** not possible to increase the size of a BLOB using this API.
! 5336: ** ^If offset iOffset is less than N bytes from the end of the BLOB,
! 5337: ** [SQLITE_ERROR] is returned and no data is written. ^If N is
! 5338: ** less than zero [SQLITE_ERROR] is returned and no data is written.
! 5339: ** The size of the BLOB (and hence the maximum value of N+iOffset)
! 5340: ** can be determined using the [sqlite3_blob_bytes()] interface.
! 5341: **
! 5342: ** ^An attempt to write to an expired [BLOB handle] fails with an
! 5343: ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred
! 5344: ** before the [BLOB handle] expired are not rolled back by the
! 5345: ** expiration of the handle, though of course those changes might
! 5346: ** have been overwritten by the statement that expired the BLOB handle
! 5347: ** or by other independent statements.
! 5348: **
! 5349: ** ^(On success, sqlite3_blob_write() returns SQLITE_OK.
! 5350: ** Otherwise, an [error code] or an [extended error code] is returned.)^
! 5351: **
! 5352: ** This routine only works on a [BLOB handle] which has been created
! 5353: ** by a prior successful call to [sqlite3_blob_open()] and which has not
! 5354: ** been closed by [sqlite3_blob_close()]. Passing any other pointer in
! 5355: ** to this routine results in undefined and probably undesirable behavior.
! 5356: **
! 5357: ** See also: [sqlite3_blob_read()].
! 5358: */
! 5359: SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset);
! 5360:
! 5361: /*
! 5362: ** CAPI3REF: Virtual File System Objects
! 5363: **
! 5364: ** A virtual filesystem (VFS) is an [sqlite3_vfs] object
! 5365: ** that SQLite uses to interact
! 5366: ** with the underlying operating system. Most SQLite builds come with a
! 5367: ** single default VFS that is appropriate for the host computer.
! 5368: ** New VFSes can be registered and existing VFSes can be unregistered.
! 5369: ** The following interfaces are provided.
! 5370: **
! 5371: ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.
! 5372: ** ^Names are case sensitive.
! 5373: ** ^Names are zero-terminated UTF-8 strings.
! 5374: ** ^If there is no match, a NULL pointer is returned.
! 5375: ** ^If zVfsName is NULL then the default VFS is returned.
! 5376: **
! 5377: ** ^New VFSes are registered with sqlite3_vfs_register().
! 5378: ** ^Each new VFS becomes the default VFS if the makeDflt flag is set.
! 5379: ** ^The same VFS can be registered multiple times without injury.
! 5380: ** ^To make an existing VFS into the default VFS, register it again
! 5381: ** with the makeDflt flag set. If two different VFSes with the
! 5382: ** same name are registered, the behavior is undefined. If a
! 5383: ** VFS is registered with a name that is NULL or an empty string,
! 5384: ** then the behavior is undefined.
! 5385: **
! 5386: ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.
! 5387: ** ^(If the default VFS is unregistered, another VFS is chosen as
! 5388: ** the default. The choice for the new VFS is arbitrary.)^
! 5389: */
! 5390: SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName);
! 5391: SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt);
! 5392: SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
! 5393:
! 5394: /*
! 5395: ** CAPI3REF: Mutexes
! 5396: **
! 5397: ** The SQLite core uses these routines for thread
! 5398: ** synchronization. Though they are intended for internal
! 5399: ** use by SQLite, code that links against SQLite is
! 5400: ** permitted to use any of these routines.
! 5401: **
! 5402: ** The SQLite source code contains multiple implementations
! 5403: ** of these mutex routines. An appropriate implementation
! 5404: ** is selected automatically at compile-time. ^(The following
! 5405: ** implementations are available in the SQLite core:
! 5406: **
! 5407: ** <ul>
! 5408: ** <li> SQLITE_MUTEX_OS2
! 5409: ** <li> SQLITE_MUTEX_PTHREADS
! 5410: ** <li> SQLITE_MUTEX_W32
! 5411: ** <li> SQLITE_MUTEX_NOOP
! 5412: ** </ul>)^
! 5413: **
! 5414: ** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
! 5415: ** that does no real locking and is appropriate for use in
! 5416: ** a single-threaded application. ^The SQLITE_MUTEX_OS2,
! 5417: ** SQLITE_MUTEX_PTHREADS, and SQLITE_MUTEX_W32 implementations
! 5418: ** are appropriate for use on OS/2, Unix, and Windows.
! 5419: **
! 5420: ** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
! 5421: ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
! 5422: ** implementation is included with the library. In this case the
! 5423: ** application must supply a custom mutex implementation using the
! 5424: ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
! 5425: ** before calling sqlite3_initialize() or any other public sqlite3_
! 5426: ** function that calls sqlite3_initialize().)^
! 5427: **
! 5428: ** ^The sqlite3_mutex_alloc() routine allocates a new
! 5429: ** mutex and returns a pointer to it. ^If it returns NULL
! 5430: ** that means that a mutex could not be allocated. ^SQLite
! 5431: ** will unwind its stack and return an error. ^(The argument
! 5432: ** to sqlite3_mutex_alloc() is one of these integer constants:
! 5433: **
! 5434: ** <ul>
! 5435: ** <li> SQLITE_MUTEX_FAST
! 5436: ** <li> SQLITE_MUTEX_RECURSIVE
! 5437: ** <li> SQLITE_MUTEX_STATIC_MASTER
! 5438: ** <li> SQLITE_MUTEX_STATIC_MEM
! 5439: ** <li> SQLITE_MUTEX_STATIC_MEM2
! 5440: ** <li> SQLITE_MUTEX_STATIC_PRNG
! 5441: ** <li> SQLITE_MUTEX_STATIC_LRU
! 5442: ** <li> SQLITE_MUTEX_STATIC_LRU2
! 5443: ** </ul>)^
! 5444: **
! 5445: ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)
! 5446: ** cause sqlite3_mutex_alloc() to create
! 5447: ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
! 5448: ** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
! 5449: ** The mutex implementation does not need to make a distinction
! 5450: ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
! 5451: ** not want to. ^SQLite will only request a recursive mutex in
! 5452: ** cases where it really needs one. ^If a faster non-recursive mutex
! 5453: ** implementation is available on the host platform, the mutex subsystem
! 5454: ** might return such a mutex in response to SQLITE_MUTEX_FAST.
! 5455: **
! 5456: ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other
! 5457: ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return
! 5458: ** a pointer to a static preexisting mutex. ^Six static mutexes are
! 5459: ** used by the current version of SQLite. Future versions of SQLite
! 5460: ** may add additional static mutexes. Static mutexes are for internal
! 5461: ** use by SQLite only. Applications that use SQLite mutexes should
! 5462: ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
! 5463: ** SQLITE_MUTEX_RECURSIVE.
! 5464: **
! 5465: ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
! 5466: ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
! 5467: ** returns a different mutex on every call. ^But for the static
! 5468: ** mutex types, the same mutex is returned on every call that has
! 5469: ** the same type number.
! 5470: **
! 5471: ** ^The sqlite3_mutex_free() routine deallocates a previously
! 5472: ** allocated dynamic mutex. ^SQLite is careful to deallocate every
! 5473: ** dynamic mutex that it allocates. The dynamic mutexes must not be in
! 5474: ** use when they are deallocated. Attempting to deallocate a static
! 5475: ** mutex results in undefined behavior. ^SQLite never deallocates
! 5476: ** a static mutex.
! 5477: **
! 5478: ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
! 5479: ** to enter a mutex. ^If another thread is already within the mutex,
! 5480: ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
! 5481: ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]
! 5482: ** upon successful entry. ^(Mutexes created using
! 5483: ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.
! 5484: ** In such cases the,
! 5485: ** mutex must be exited an equal number of times before another thread
! 5486: ** can enter.)^ ^(If the same thread tries to enter any other
! 5487: ** kind of mutex more than once, the behavior is undefined.
! 5488: ** SQLite will never exhibit
! 5489: ** such behavior in its own use of mutexes.)^
! 5490: **
! 5491: ** ^(Some systems (for example, Windows 95) do not support the operation
! 5492: ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()
! 5493: ** will always return SQLITE_BUSY. The SQLite core only ever uses
! 5494: ** sqlite3_mutex_try() as an optimization so this is acceptable behavior.)^
! 5495: **
! 5496: ** ^The sqlite3_mutex_leave() routine exits a mutex that was
! 5497: ** previously entered by the same thread. ^(The behavior
! 5498: ** is undefined if the mutex is not currently entered by the
! 5499: ** calling thread or is not currently allocated. SQLite will
! 5500: ** never do either.)^
! 5501: **
! 5502: ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
! 5503: ** sqlite3_mutex_leave() is a NULL pointer, then all three routines
! 5504: ** behave as no-ops.
! 5505: **
! 5506: ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
! 5507: */
! 5508: SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int);
! 5509: SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*);
! 5510: SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*);
! 5511: SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*);
! 5512: SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*);
! 5513:
! 5514: /*
! 5515: ** CAPI3REF: Mutex Methods Object
! 5516: **
! 5517: ** An instance of this structure defines the low-level routines
! 5518: ** used to allocate and use mutexes.
! 5519: **
! 5520: ** Usually, the default mutex implementations provided by SQLite are
! 5521: ** sufficient, however the user has the option of substituting a custom
! 5522: ** implementation for specialized deployments or systems for which SQLite
! 5523: ** does not provide a suitable implementation. In this case, the user
! 5524: ** creates and populates an instance of this structure to pass
! 5525: ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.
! 5526: ** Additionally, an instance of this structure can be used as an
! 5527: ** output variable when querying the system for the current mutex
! 5528: ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.
! 5529: **
! 5530: ** ^The xMutexInit method defined by this structure is invoked as
! 5531: ** part of system initialization by the sqlite3_initialize() function.
! 5532: ** ^The xMutexInit routine is called by SQLite exactly once for each
! 5533: ** effective call to [sqlite3_initialize()].
! 5534: **
! 5535: ** ^The xMutexEnd method defined by this structure is invoked as
! 5536: ** part of system shutdown by the sqlite3_shutdown() function. The
! 5537: ** implementation of this method is expected to release all outstanding
! 5538: ** resources obtained by the mutex methods implementation, especially
! 5539: ** those obtained by the xMutexInit method. ^The xMutexEnd()
! 5540: ** interface is invoked exactly once for each call to [sqlite3_shutdown()].
! 5541: **
! 5542: ** ^(The remaining seven methods defined by this structure (xMutexAlloc,
! 5543: ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and
! 5544: ** xMutexNotheld) implement the following interfaces (respectively):
! 5545: **
! 5546: ** <ul>
! 5547: ** <li> [sqlite3_mutex_alloc()] </li>
! 5548: ** <li> [sqlite3_mutex_free()] </li>
! 5549: ** <li> [sqlite3_mutex_enter()] </li>
! 5550: ** <li> [sqlite3_mutex_try()] </li>
! 5551: ** <li> [sqlite3_mutex_leave()] </li>
! 5552: ** <li> [sqlite3_mutex_held()] </li>
! 5553: ** <li> [sqlite3_mutex_notheld()] </li>
! 5554: ** </ul>)^
! 5555: **
! 5556: ** The only difference is that the public sqlite3_XXX functions enumerated
! 5557: ** above silently ignore any invocations that pass a NULL pointer instead
! 5558: ** of a valid mutex handle. The implementations of the methods defined
! 5559: ** by this structure are not required to handle this case, the results
! 5560: ** of passing a NULL pointer instead of a valid mutex handle are undefined
! 5561: ** (i.e. it is acceptable to provide an implementation that segfaults if
! 5562: ** it is passed a NULL pointer).
! 5563: **
! 5564: ** The xMutexInit() method must be threadsafe. ^It must be harmless to
! 5565: ** invoke xMutexInit() multiple times within the same process and without
! 5566: ** intervening calls to xMutexEnd(). Second and subsequent calls to
! 5567: ** xMutexInit() must be no-ops.
! 5568: **
! 5569: ** ^xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]
! 5570: ** and its associates). ^Similarly, xMutexAlloc() must not use SQLite memory
! 5571: ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite
! 5572: ** memory allocation for a fast or recursive mutex.
! 5573: **
! 5574: ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is
! 5575: ** called, but only if the prior call to xMutexInit returned SQLITE_OK.
! 5576: ** If xMutexInit fails in any way, it is expected to clean up after itself
! 5577: ** prior to returning.
! 5578: */
! 5579: typedef struct sqlite3_mutex_methods sqlite3_mutex_methods;
! 5580: struct sqlite3_mutex_methods {
! 5581: int (*xMutexInit)(void);
! 5582: int (*xMutexEnd)(void);
! 5583: sqlite3_mutex *(*xMutexAlloc)(int);
! 5584: void (*xMutexFree)(sqlite3_mutex *);
! 5585: void (*xMutexEnter)(sqlite3_mutex *);
! 5586: int (*xMutexTry)(sqlite3_mutex *);
! 5587: void (*xMutexLeave)(sqlite3_mutex *);
! 5588: int (*xMutexHeld)(sqlite3_mutex *);
! 5589: int (*xMutexNotheld)(sqlite3_mutex *);
! 5590: };
! 5591:
! 5592: /*
! 5593: ** CAPI3REF: Mutex Verification Routines
! 5594: **
! 5595: ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines
! 5596: ** are intended for use inside assert() statements. ^The SQLite core
! 5597: ** never uses these routines except inside an assert() and applications
! 5598: ** are advised to follow the lead of the core. ^The SQLite core only
! 5599: ** provides implementations for these routines when it is compiled
! 5600: ** with the SQLITE_DEBUG flag. ^External mutex implementations
! 5601: ** are only required to provide these routines if SQLITE_DEBUG is
! 5602: ** defined and if NDEBUG is not defined.
! 5603: **
! 5604: ** ^These routines should return true if the mutex in their argument
! 5605: ** is held or not held, respectively, by the calling thread.
! 5606: **
! 5607: ** ^The implementation is not required to provide versions of these
! 5608: ** routines that actually work. If the implementation does not provide working
! 5609: ** versions of these routines, it should at least provide stubs that always
! 5610: ** return true so that one does not get spurious assertion failures.
! 5611: **
! 5612: ** ^If the argument to sqlite3_mutex_held() is a NULL pointer then
! 5613: ** the routine should return 1. This seems counter-intuitive since
! 5614: ** clearly the mutex cannot be held if it does not exist. But
! 5615: ** the reason the mutex does not exist is because the build is not
! 5616: ** using mutexes. And we do not want the assert() containing the
! 5617: ** call to sqlite3_mutex_held() to fail, so a non-zero return is
! 5618: ** the appropriate thing to do. ^The sqlite3_mutex_notheld()
! 5619: ** interface should also return 1 when given a NULL pointer.
! 5620: */
! 5621: #ifndef NDEBUG
! 5622: SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*);
! 5623: SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*);
! 5624: #endif
! 5625:
! 5626: /*
! 5627: ** CAPI3REF: Mutex Types
! 5628: **
! 5629: ** The [sqlite3_mutex_alloc()] interface takes a single argument
! 5630: ** which is one of these integer constants.
! 5631: **
! 5632: ** The set of static mutexes may change from one SQLite release to the
! 5633: ** next. Applications that override the built-in mutex logic must be
! 5634: ** prepared to accommodate additional static mutexes.
! 5635: */
! 5636: #define SQLITE_MUTEX_FAST 0
! 5637: #define SQLITE_MUTEX_RECURSIVE 1
! 5638: #define SQLITE_MUTEX_STATIC_MASTER 2
! 5639: #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */
! 5640: #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */
! 5641: #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */
! 5642: #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */
! 5643: #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */
! 5644: #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */
! 5645: #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */
! 5646:
! 5647: /*
! 5648: ** CAPI3REF: Retrieve the mutex for a database connection
! 5649: **
! 5650: ** ^This interface returns a pointer the [sqlite3_mutex] object that
! 5651: ** serializes access to the [database connection] given in the argument
! 5652: ** when the [threading mode] is Serialized.
! 5653: ** ^If the [threading mode] is Single-thread or Multi-thread then this
! 5654: ** routine returns a NULL pointer.
! 5655: */
! 5656: SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*);
! 5657:
! 5658: /*
! 5659: ** CAPI3REF: Low-Level Control Of Database Files
! 5660: **
! 5661: ** ^The [sqlite3_file_control()] interface makes a direct call to the
! 5662: ** xFileControl method for the [sqlite3_io_methods] object associated
! 5663: ** with a particular database identified by the second argument. ^The
! 5664: ** name of the database is "main" for the main database or "temp" for the
! 5665: ** TEMP database, or the name that appears after the AS keyword for
! 5666: ** databases that are added using the [ATTACH] SQL command.
! 5667: ** ^A NULL pointer can be used in place of "main" to refer to the
! 5668: ** main database file.
! 5669: ** ^The third and fourth parameters to this routine
! 5670: ** are passed directly through to the second and third parameters of
! 5671: ** the xFileControl method. ^The return value of the xFileControl
! 5672: ** method becomes the return value of this routine.
! 5673: **
! 5674: ** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes
! 5675: ** a pointer to the underlying [sqlite3_file] object to be written into
! 5676: ** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER
! 5677: ** case is a short-circuit path which does not actually invoke the
! 5678: ** underlying sqlite3_io_methods.xFileControl method.
! 5679: **
! 5680: ** ^If the second parameter (zDbName) does not match the name of any
! 5681: ** open database file, then SQLITE_ERROR is returned. ^This error
! 5682: ** code is not remembered and will not be recalled by [sqlite3_errcode()]
! 5683: ** or [sqlite3_errmsg()]. The underlying xFileControl method might
! 5684: ** also return SQLITE_ERROR. There is no way to distinguish between
! 5685: ** an incorrect zDbName and an SQLITE_ERROR return from the underlying
! 5686: ** xFileControl method.
! 5687: **
! 5688: ** See also: [SQLITE_FCNTL_LOCKSTATE]
! 5689: */
! 5690: SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*);
! 5691:
! 5692: /*
! 5693: ** CAPI3REF: Testing Interface
! 5694: **
! 5695: ** ^The sqlite3_test_control() interface is used to read out internal
! 5696: ** state of SQLite and to inject faults into SQLite for testing
! 5697: ** purposes. ^The first parameter is an operation code that determines
! 5698: ** the number, meaning, and operation of all subsequent parameters.
! 5699: **
! 5700: ** This interface is not for use by applications. It exists solely
! 5701: ** for verifying the correct operation of the SQLite library. Depending
! 5702: ** on how the SQLite library is compiled, this interface might not exist.
! 5703: **
! 5704: ** The details of the operation codes, their meanings, the parameters
! 5705: ** they take, and what they do are all subject to change without notice.
! 5706: ** Unlike most of the SQLite API, this function is not guaranteed to
! 5707: ** operate consistently from one release to the next.
! 5708: */
! 5709: SQLITE_API int sqlite3_test_control(int op, ...);
! 5710:
! 5711: /*
! 5712: ** CAPI3REF: Testing Interface Operation Codes
! 5713: **
! 5714: ** These constants are the valid operation code parameters used
! 5715: ** as the first argument to [sqlite3_test_control()].
! 5716: **
! 5717: ** These parameters and their meanings are subject to change
! 5718: ** without notice. These values are for testing purposes only.
! 5719: ** Applications should not use any of these parameters or the
! 5720: ** [sqlite3_test_control()] interface.
! 5721: */
! 5722: #define SQLITE_TESTCTRL_FIRST 5
! 5723: #define SQLITE_TESTCTRL_PRNG_SAVE 5
! 5724: #define SQLITE_TESTCTRL_PRNG_RESTORE 6
! 5725: #define SQLITE_TESTCTRL_PRNG_RESET 7
! 5726: #define SQLITE_TESTCTRL_BITVEC_TEST 8
! 5727: #define SQLITE_TESTCTRL_FAULT_INSTALL 9
! 5728: #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10
! 5729: #define SQLITE_TESTCTRL_PENDING_BYTE 11
! 5730: #define SQLITE_TESTCTRL_ASSERT 12
! 5731: #define SQLITE_TESTCTRL_ALWAYS 13
! 5732: #define SQLITE_TESTCTRL_RESERVE 14
! 5733: #define SQLITE_TESTCTRL_OPTIMIZATIONS 15
! 5734: #define SQLITE_TESTCTRL_ISKEYWORD 16
! 5735: #define SQLITE_TESTCTRL_SCRATCHMALLOC 17
! 5736: #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18
! 5737: #define SQLITE_TESTCTRL_EXPLAIN_STMT 19
! 5738: #define SQLITE_TESTCTRL_LAST 19
! 5739:
! 5740: /*
! 5741: ** CAPI3REF: SQLite Runtime Status
! 5742: **
! 5743: ** ^This interface is used to retrieve runtime status information
! 5744: ** about the performance of SQLite, and optionally to reset various
! 5745: ** highwater marks. ^The first argument is an integer code for
! 5746: ** the specific parameter to measure. ^(Recognized integer codes
! 5747: ** are of the form [status parameters | SQLITE_STATUS_...].)^
! 5748: ** ^The current value of the parameter is returned into *pCurrent.
! 5749: ** ^The highest recorded value is returned in *pHighwater. ^If the
! 5750: ** resetFlag is true, then the highest record value is reset after
! 5751: ** *pHighwater is written. ^(Some parameters do not record the highest
! 5752: ** value. For those parameters
! 5753: ** nothing is written into *pHighwater and the resetFlag is ignored.)^
! 5754: ** ^(Other parameters record only the highwater mark and not the current
! 5755: ** value. For these latter parameters nothing is written into *pCurrent.)^
! 5756: **
! 5757: ** ^The sqlite3_status() routine returns SQLITE_OK on success and a
! 5758: ** non-zero [error code] on failure.
! 5759: **
! 5760: ** This routine is threadsafe but is not atomic. This routine can be
! 5761: ** called while other threads are running the same or different SQLite
! 5762: ** interfaces. However the values returned in *pCurrent and
! 5763: ** *pHighwater reflect the status of SQLite at different points in time
! 5764: ** and it is possible that another thread might change the parameter
! 5765: ** in between the times when *pCurrent and *pHighwater are written.
! 5766: **
! 5767: ** See also: [sqlite3_db_status()]
! 5768: */
! 5769: SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);
! 5770:
! 5771:
! 5772: /*
! 5773: ** CAPI3REF: Status Parameters
! 5774: ** KEYWORDS: {status parameters}
! 5775: **
! 5776: ** These integer constants designate various run-time status parameters
! 5777: ** that can be returned by [sqlite3_status()].
! 5778: **
! 5779: ** <dl>
! 5780: ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>
! 5781: ** <dd>This parameter is the current amount of memory checked out
! 5782: ** using [sqlite3_malloc()], either directly or indirectly. The
! 5783: ** figure includes calls made to [sqlite3_malloc()] by the application
! 5784: ** and internal memory usage by the SQLite library. Scratch memory
! 5785: ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache
! 5786: ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in
! 5787: ** this parameter. The amount returned is the sum of the allocation
! 5788: ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^
! 5789: **
! 5790: ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>
! 5791: ** <dd>This parameter records the largest memory allocation request
! 5792: ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their
! 5793: ** internal equivalents). Only the value returned in the
! 5794: ** *pHighwater parameter to [sqlite3_status()] is of interest.
! 5795: ** The value written into the *pCurrent parameter is undefined.</dd>)^
! 5796: **
! 5797: ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>
! 5798: ** <dd>This parameter records the number of separate memory allocations
! 5799: ** currently checked out.</dd>)^
! 5800: **
! 5801: ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>
! 5802: ** <dd>This parameter returns the number of pages used out of the
! 5803: ** [pagecache memory allocator] that was configured using
! 5804: ** [SQLITE_CONFIG_PAGECACHE]. The
! 5805: ** value returned is in pages, not in bytes.</dd>)^
! 5806: **
! 5807: ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]]
! 5808: ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>
! 5809: ** <dd>This parameter returns the number of bytes of page cache
! 5810: ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]
! 5811: ** buffer and where forced to overflow to [sqlite3_malloc()]. The
! 5812: ** returned value includes allocations that overflowed because they
! 5813: ** where too large (they were larger than the "sz" parameter to
! 5814: ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because
! 5815: ** no space was left in the page cache.</dd>)^
! 5816: **
! 5817: ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>
! 5818: ** <dd>This parameter records the largest memory allocation request
! 5819: ** handed to [pagecache memory allocator]. Only the value returned in the
! 5820: ** *pHighwater parameter to [sqlite3_status()] is of interest.
! 5821: ** The value written into the *pCurrent parameter is undefined.</dd>)^
! 5822: **
! 5823: ** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>
! 5824: ** <dd>This parameter returns the number of allocations used out of the
! 5825: ** [scratch memory allocator] configured using
! 5826: ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not
! 5827: ** in bytes. Since a single thread may only have one scratch allocation
! 5828: ** outstanding at time, this parameter also reports the number of threads
! 5829: ** using scratch memory at the same time.</dd>)^
! 5830: **
! 5831: ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>
! 5832: ** <dd>This parameter returns the number of bytes of scratch memory
! 5833: ** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]
! 5834: ** buffer and where forced to overflow to [sqlite3_malloc()]. The values
! 5835: ** returned include overflows because the requested allocation was too
! 5836: ** larger (that is, because the requested allocation was larger than the
! 5837: ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer
! 5838: ** slots were available.
! 5839: ** </dd>)^
! 5840: **
! 5841: ** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>
! 5842: ** <dd>This parameter records the largest memory allocation request
! 5843: ** handed to [scratch memory allocator]. Only the value returned in the
! 5844: ** *pHighwater parameter to [sqlite3_status()] is of interest.
! 5845: ** The value written into the *pCurrent parameter is undefined.</dd>)^
! 5846: **
! 5847: ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>
! 5848: ** <dd>This parameter records the deepest parser stack. It is only
! 5849: ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^
! 5850: ** </dl>
! 5851: **
! 5852: ** New status parameters may be added from time to time.
! 5853: */
! 5854: #define SQLITE_STATUS_MEMORY_USED 0
! 5855: #define SQLITE_STATUS_PAGECACHE_USED 1
! 5856: #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2
! 5857: #define SQLITE_STATUS_SCRATCH_USED 3
! 5858: #define SQLITE_STATUS_SCRATCH_OVERFLOW 4
! 5859: #define SQLITE_STATUS_MALLOC_SIZE 5
! 5860: #define SQLITE_STATUS_PARSER_STACK 6
! 5861: #define SQLITE_STATUS_PAGECACHE_SIZE 7
! 5862: #define SQLITE_STATUS_SCRATCH_SIZE 8
! 5863: #define SQLITE_STATUS_MALLOC_COUNT 9
! 5864:
! 5865: /*
! 5866: ** CAPI3REF: Database Connection Status
! 5867: **
! 5868: ** ^This interface is used to retrieve runtime status information
! 5869: ** about a single [database connection]. ^The first argument is the
! 5870: ** database connection object to be interrogated. ^The second argument
! 5871: ** is an integer constant, taken from the set of
! 5872: ** [SQLITE_DBSTATUS options], that
! 5873: ** determines the parameter to interrogate. The set of
! 5874: ** [SQLITE_DBSTATUS options] is likely
! 5875: ** to grow in future releases of SQLite.
! 5876: **
! 5877: ** ^The current value of the requested parameter is written into *pCur
! 5878: ** and the highest instantaneous value is written into *pHiwtr. ^If
! 5879: ** the resetFlg is true, then the highest instantaneous value is
! 5880: ** reset back down to the current value.
! 5881: **
! 5882: ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a
! 5883: ** non-zero [error code] on failure.
! 5884: **
! 5885: ** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
! 5886: */
! 5887: SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);
! 5888:
! 5889: /*
! 5890: ** CAPI3REF: Status Parameters for database connections
! 5891: ** KEYWORDS: {SQLITE_DBSTATUS options}
! 5892: **
! 5893: ** These constants are the available integer "verbs" that can be passed as
! 5894: ** the second argument to the [sqlite3_db_status()] interface.
! 5895: **
! 5896: ** New verbs may be added in future releases of SQLite. Existing verbs
! 5897: ** might be discontinued. Applications should check the return code from
! 5898: ** [sqlite3_db_status()] to make sure that the call worked.
! 5899: ** The [sqlite3_db_status()] interface will return a non-zero error code
! 5900: ** if a discontinued or unsupported verb is invoked.
! 5901: **
! 5902: ** <dl>
! 5903: ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
! 5904: ** <dd>This parameter returns the number of lookaside memory slots currently
! 5905: ** checked out.</dd>)^
! 5906: **
! 5907: ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>
! 5908: ** <dd>This parameter returns the number malloc attempts that were
! 5909: ** satisfied using lookaside memory. Only the high-water value is meaningful;
! 5910: ** the current value is always zero.)^
! 5911: **
! 5912: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]
! 5913: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>
! 5914: ** <dd>This parameter returns the number malloc attempts that might have
! 5915: ** been satisfied using lookaside memory but failed due to the amount of
! 5916: ** memory requested being larger than the lookaside slot size.
! 5917: ** Only the high-water value is meaningful;
! 5918: ** the current value is always zero.)^
! 5919: **
! 5920: ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]
! 5921: ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>
! 5922: ** <dd>This parameter returns the number malloc attempts that might have
! 5923: ** been satisfied using lookaside memory but failed due to all lookaside
! 5924: ** memory already being in use.
! 5925: ** Only the high-water value is meaningful;
! 5926: ** the current value is always zero.)^
! 5927: **
! 5928: ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>
! 5929: ** <dd>This parameter returns the approximate number of of bytes of heap
! 5930: ** memory used by all pager caches associated with the database connection.)^
! 5931: ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.
! 5932: **
! 5933: ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>
! 5934: ** <dd>This parameter returns the approximate number of of bytes of heap
! 5935: ** memory used to store the schema for all databases associated
! 5936: ** with the connection - main, temp, and any [ATTACH]-ed databases.)^
! 5937: ** ^The full amount of memory used by the schemas is reported, even if the
! 5938: ** schema memory is shared with other database connections due to
! 5939: ** [shared cache mode] being enabled.
! 5940: ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.
! 5941: **
! 5942: ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>
! 5943: ** <dd>This parameter returns the approximate number of of bytes of heap
! 5944: ** and lookaside memory used by all prepared statements associated with
! 5945: ** the database connection.)^
! 5946: ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.
! 5947: ** </dd>
! 5948: **
! 5949: ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>
! 5950: ** <dd>This parameter returns the number of pager cache hits that have
! 5951: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT
! 5952: ** is always 0.
! 5953: ** </dd>
! 5954: **
! 5955: ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>
! 5956: ** <dd>This parameter returns the number of pager cache misses that have
! 5957: ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS
! 5958: ** is always 0.
! 5959: ** </dd>
! 5960: ** </dl>
! 5961: */
! 5962: #define SQLITE_DBSTATUS_LOOKASIDE_USED 0
! 5963: #define SQLITE_DBSTATUS_CACHE_USED 1
! 5964: #define SQLITE_DBSTATUS_SCHEMA_USED 2
! 5965: #define SQLITE_DBSTATUS_STMT_USED 3
! 5966: #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4
! 5967: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5
! 5968: #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6
! 5969: #define SQLITE_DBSTATUS_CACHE_HIT 7
! 5970: #define SQLITE_DBSTATUS_CACHE_MISS 8
! 5971: #define SQLITE_DBSTATUS_MAX 8 /* Largest defined DBSTATUS */
! 5972:
! 5973:
! 5974: /*
! 5975: ** CAPI3REF: Prepared Statement Status
! 5976: **
! 5977: ** ^(Each prepared statement maintains various
! 5978: ** [SQLITE_STMTSTATUS counters] that measure the number
! 5979: ** of times it has performed specific operations.)^ These counters can
! 5980: ** be used to monitor the performance characteristics of the prepared
! 5981: ** statements. For example, if the number of table steps greatly exceeds
! 5982: ** the number of table searches or result rows, that would tend to indicate
! 5983: ** that the prepared statement is using a full table scan rather than
! 5984: ** an index.
! 5985: **
! 5986: ** ^(This interface is used to retrieve and reset counter values from
! 5987: ** a [prepared statement]. The first argument is the prepared statement
! 5988: ** object to be interrogated. The second argument
! 5989: ** is an integer code for a specific [SQLITE_STMTSTATUS counter]
! 5990: ** to be interrogated.)^
! 5991: ** ^The current value of the requested counter is returned.
! 5992: ** ^If the resetFlg is true, then the counter is reset to zero after this
! 5993: ** interface call returns.
! 5994: **
! 5995: ** See also: [sqlite3_status()] and [sqlite3_db_status()].
! 5996: */
! 5997: SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
! 5998:
! 5999: /*
! 6000: ** CAPI3REF: Status Parameters for prepared statements
! 6001: ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}
! 6002: **
! 6003: ** These preprocessor macros define integer codes that name counter
! 6004: ** values associated with the [sqlite3_stmt_status()] interface.
! 6005: ** The meanings of the various counters are as follows:
! 6006: **
! 6007: ** <dl>
! 6008: ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
! 6009: ** <dd>^This is the number of times that SQLite has stepped forward in
! 6010: ** a table as part of a full table scan. Large numbers for this counter
! 6011: ** may indicate opportunities for performance improvement through
! 6012: ** careful use of indices.</dd>
! 6013: **
! 6014: ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>
! 6015: ** <dd>^This is the number of sort operations that have occurred.
! 6016: ** A non-zero value in this counter may indicate an opportunity to
! 6017: ** improvement performance through careful use of indices.</dd>
! 6018: **
! 6019: ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>
! 6020: ** <dd>^This is the number of rows inserted into transient indices that
! 6021: ** were created automatically in order to help joins run faster.
! 6022: ** A non-zero value in this counter may indicate an opportunity to
! 6023: ** improvement performance by adding permanent indices that do not
! 6024: ** need to be reinitialized each time the statement is run.</dd>
! 6025: ** </dl>
! 6026: */
! 6027: #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1
! 6028: #define SQLITE_STMTSTATUS_SORT 2
! 6029: #define SQLITE_STMTSTATUS_AUTOINDEX 3
! 6030:
! 6031: /*
! 6032: ** CAPI3REF: Custom Page Cache Object
! 6033: **
! 6034: ** The sqlite3_pcache type is opaque. It is implemented by
! 6035: ** the pluggable module. The SQLite core has no knowledge of
! 6036: ** its size or internal structure and never deals with the
! 6037: ** sqlite3_pcache object except by holding and passing pointers
! 6038: ** to the object.
! 6039: **
! 6040: ** See [sqlite3_pcache_methods2] for additional information.
! 6041: */
! 6042: typedef struct sqlite3_pcache sqlite3_pcache;
! 6043:
! 6044: /*
! 6045: ** CAPI3REF: Custom Page Cache Object
! 6046: **
! 6047: ** The sqlite3_pcache_page object represents a single page in the
! 6048: ** page cache. The page cache will allocate instances of this
! 6049: ** object. Various methods of the page cache use pointers to instances
! 6050: ** of this object as parameters or as their return value.
! 6051: **
! 6052: ** See [sqlite3_pcache_methods2] for additional information.
! 6053: */
! 6054: typedef struct sqlite3_pcache_page sqlite3_pcache_page;
! 6055: struct sqlite3_pcache_page {
! 6056: void *pBuf; /* The content of the page */
! 6057: void *pExtra; /* Extra information associated with the page */
! 6058: };
! 6059:
! 6060: /*
! 6061: ** CAPI3REF: Application Defined Page Cache.
! 6062: ** KEYWORDS: {page cache}
! 6063: **
! 6064: ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can
! 6065: ** register an alternative page cache implementation by passing in an
! 6066: ** instance of the sqlite3_pcache_methods2 structure.)^
! 6067: ** In many applications, most of the heap memory allocated by
! 6068: ** SQLite is used for the page cache.
! 6069: ** By implementing a
! 6070: ** custom page cache using this API, an application can better control
! 6071: ** the amount of memory consumed by SQLite, the way in which
! 6072: ** that memory is allocated and released, and the policies used to
! 6073: ** determine exactly which parts of a database file are cached and for
! 6074: ** how long.
! 6075: **
! 6076: ** The alternative page cache mechanism is an
! 6077: ** extreme measure that is only needed by the most demanding applications.
! 6078: ** The built-in page cache is recommended for most uses.
! 6079: **
! 6080: ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an
! 6081: ** internal buffer by SQLite within the call to [sqlite3_config]. Hence
! 6082: ** the application may discard the parameter after the call to
! 6083: ** [sqlite3_config()] returns.)^
! 6084: **
! 6085: ** [[the xInit() page cache method]]
! 6086: ** ^(The xInit() method is called once for each effective
! 6087: ** call to [sqlite3_initialize()])^
! 6088: ** (usually only once during the lifetime of the process). ^(The xInit()
! 6089: ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^
! 6090: ** The intent of the xInit() method is to set up global data structures
! 6091: ** required by the custom page cache implementation.
! 6092: ** ^(If the xInit() method is NULL, then the
! 6093: ** built-in default page cache is used instead of the application defined
! 6094: ** page cache.)^
! 6095: **
! 6096: ** [[the xShutdown() page cache method]]
! 6097: ** ^The xShutdown() method is called by [sqlite3_shutdown()].
! 6098: ** It can be used to clean up
! 6099: ** any outstanding resources before process shutdown, if required.
! 6100: ** ^The xShutdown() method may be NULL.
! 6101: **
! 6102: ** ^SQLite automatically serializes calls to the xInit method,
! 6103: ** so the xInit method need not be threadsafe. ^The
! 6104: ** xShutdown method is only called from [sqlite3_shutdown()] so it does
! 6105: ** not need to be threadsafe either. All other methods must be threadsafe
! 6106: ** in multithreaded applications.
! 6107: **
! 6108: ** ^SQLite will never invoke xInit() more than once without an intervening
! 6109: ** call to xShutdown().
! 6110: **
! 6111: ** [[the xCreate() page cache methods]]
! 6112: ** ^SQLite invokes the xCreate() method to construct a new cache instance.
! 6113: ** SQLite will typically create one cache instance for each open database file,
! 6114: ** though this is not guaranteed. ^The
! 6115: ** first parameter, szPage, is the size in bytes of the pages that must
! 6116: ** be allocated by the cache. ^szPage will always a power of two. ^The
! 6117: ** second parameter szExtra is a number of bytes of extra storage
! 6118: ** associated with each page cache entry. ^The szExtra parameter will
! 6119: ** a number less than 250. SQLite will use the
! 6120: ** extra szExtra bytes on each page to store metadata about the underlying
! 6121: ** database page on disk. The value passed into szExtra depends
! 6122: ** on the SQLite version, the target platform, and how SQLite was compiled.
! 6123: ** ^The third argument to xCreate(), bPurgeable, is true if the cache being
! 6124: ** created will be used to cache database pages of a file stored on disk, or
! 6125: ** false if it is used for an in-memory database. The cache implementation
! 6126: ** does not have to do anything special based with the value of bPurgeable;
! 6127: ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will
! 6128: ** never invoke xUnpin() except to deliberately delete a page.
! 6129: ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to
! 6130: ** false will always have the "discard" flag set to true.
! 6131: ** ^Hence, a cache created with bPurgeable false will
! 6132: ** never contain any unpinned pages.
! 6133: **
! 6134: ** [[the xCachesize() page cache method]]
! 6135: ** ^(The xCachesize() method may be called at any time by SQLite to set the
! 6136: ** suggested maximum cache-size (number of pages stored by) the cache
! 6137: ** instance passed as the first argument. This is the value configured using
! 6138: ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable
! 6139: ** parameter, the implementation is not required to do anything with this
! 6140: ** value; it is advisory only.
! 6141: **
! 6142: ** [[the xPagecount() page cache methods]]
! 6143: ** The xPagecount() method must return the number of pages currently
! 6144: ** stored in the cache, both pinned and unpinned.
! 6145: **
! 6146: ** [[the xFetch() page cache methods]]
! 6147: ** The xFetch() method locates a page in the cache and returns a pointer to
! 6148: ** an sqlite3_pcache_page object associated with that page, or a NULL pointer.
! 6149: ** The pBuf element of the returned sqlite3_pcache_page object will be a
! 6150: ** pointer to a buffer of szPage bytes used to store the content of a
! 6151: ** single database page. The pExtra element of sqlite3_pcache_page will be
! 6152: ** a pointer to the szExtra bytes of extra storage that SQLite has requested
! 6153: ** for each entry in the page cache.
! 6154: **
! 6155: ** The page to be fetched is determined by the key. ^The minimum key value
! 6156: ** is 1. After it has been retrieved using xFetch, the page is considered
! 6157: ** to be "pinned".
! 6158: **
! 6159: ** If the requested page is already in the page cache, then the page cache
! 6160: ** implementation must return a pointer to the page buffer with its content
! 6161: ** intact. If the requested page is not already in the cache, then the
! 6162: ** cache implementation should use the value of the createFlag
! 6163: ** parameter to help it determined what action to take:
! 6164: **
! 6165: ** <table border=1 width=85% align=center>
! 6166: ** <tr><th> createFlag <th> Behaviour when page is not already in cache
! 6167: ** <tr><td> 0 <td> Do not allocate a new page. Return NULL.
! 6168: ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
! 6169: ** Otherwise return NULL.
! 6170: ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return
! 6171: ** NULL if allocating a new page is effectively impossible.
! 6172: ** </table>
! 6173: **
! 6174: ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite
! 6175: ** will only use a createFlag of 2 after a prior call with a createFlag of 1
! 6176: ** failed.)^ In between the to xFetch() calls, SQLite may
! 6177: ** attempt to unpin one or more cache pages by spilling the content of
! 6178: ** pinned pages to disk and synching the operating system disk cache.
! 6179: **
! 6180: ** [[the xUnpin() page cache method]]
! 6181: ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page
! 6182: ** as its second argument. If the third parameter, discard, is non-zero,
! 6183: ** then the page must be evicted from the cache.
! 6184: ** ^If the discard parameter is
! 6185: ** zero, then the page may be discarded or retained at the discretion of
! 6186: ** page cache implementation. ^The page cache implementation
! 6187: ** may choose to evict unpinned pages at any time.
! 6188: **
! 6189: ** The cache must not perform any reference counting. A single
! 6190: ** call to xUnpin() unpins the page regardless of the number of prior calls
! 6191: ** to xFetch().
! 6192: **
! 6193: ** [[the xRekey() page cache methods]]
! 6194: ** The xRekey() method is used to change the key value associated with the
! 6195: ** page passed as the second argument. If the cache
! 6196: ** previously contains an entry associated with newKey, it must be
! 6197: ** discarded. ^Any prior cache entry associated with newKey is guaranteed not
! 6198: ** to be pinned.
! 6199: **
! 6200: ** When SQLite calls the xTruncate() method, the cache must discard all
! 6201: ** existing cache entries with page numbers (keys) greater than or equal
! 6202: ** to the value of the iLimit parameter passed to xTruncate(). If any
! 6203: ** of these pages are pinned, they are implicitly unpinned, meaning that
! 6204: ** they can be safely discarded.
! 6205: **
! 6206: ** [[the xDestroy() page cache method]]
! 6207: ** ^The xDestroy() method is used to delete a cache allocated by xCreate().
! 6208: ** All resources associated with the specified cache should be freed. ^After
! 6209: ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]
! 6210: ** handle invalid, and will not use it with any other sqlite3_pcache_methods2
! 6211: ** functions.
! 6212: **
! 6213: ** [[the xShrink() page cache method]]
! 6214: ** ^SQLite invokes the xShrink() method when it wants the page cache to
! 6215: ** free up as much of heap memory as possible. The page cache implementation
! 6216: ** is not obligated to free any memory, but well-behaved implementations should
! 6217: ** do their best.
! 6218: */
! 6219: typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2;
! 6220: struct sqlite3_pcache_methods2 {
! 6221: int iVersion;
! 6222: void *pArg;
! 6223: int (*xInit)(void*);
! 6224: void (*xShutdown)(void*);
! 6225: sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
! 6226: void (*xCachesize)(sqlite3_pcache*, int nCachesize);
! 6227: int (*xPagecount)(sqlite3_pcache*);
! 6228: sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
! 6229: void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard);
! 6230: void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*,
! 6231: unsigned oldKey, unsigned newKey);
! 6232: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
! 6233: void (*xDestroy)(sqlite3_pcache*);
! 6234: void (*xShrink)(sqlite3_pcache*);
! 6235: };
! 6236:
! 6237: /*
! 6238: ** This is the obsolete pcache_methods object that has now been replaced
! 6239: ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is
! 6240: ** retained in the header file for backwards compatibility only.
! 6241: */
! 6242: typedef struct sqlite3_pcache_methods sqlite3_pcache_methods;
! 6243: struct sqlite3_pcache_methods {
! 6244: void *pArg;
! 6245: int (*xInit)(void*);
! 6246: void (*xShutdown)(void*);
! 6247: sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable);
! 6248: void (*xCachesize)(sqlite3_pcache*, int nCachesize);
! 6249: int (*xPagecount)(sqlite3_pcache*);
! 6250: void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag);
! 6251: void (*xUnpin)(sqlite3_pcache*, void*, int discard);
! 6252: void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey);
! 6253: void (*xTruncate)(sqlite3_pcache*, unsigned iLimit);
! 6254: void (*xDestroy)(sqlite3_pcache*);
! 6255: };
! 6256:
! 6257:
! 6258: /*
! 6259: ** CAPI3REF: Online Backup Object
! 6260: **
! 6261: ** The sqlite3_backup object records state information about an ongoing
! 6262: ** online backup operation. ^The sqlite3_backup object is created by
! 6263: ** a call to [sqlite3_backup_init()] and is destroyed by a call to
! 6264: ** [sqlite3_backup_finish()].
! 6265: **
! 6266: ** See Also: [Using the SQLite Online Backup API]
! 6267: */
! 6268: typedef struct sqlite3_backup sqlite3_backup;
! 6269:
! 6270: /*
! 6271: ** CAPI3REF: Online Backup API.
! 6272: **
! 6273: ** The backup API copies the content of one database into another.
! 6274: ** It is useful either for creating backups of databases or
! 6275: ** for copying in-memory databases to or from persistent files.
! 6276: **
! 6277: ** See Also: [Using the SQLite Online Backup API]
! 6278: **
! 6279: ** ^SQLite holds a write transaction open on the destination database file
! 6280: ** for the duration of the backup operation.
! 6281: ** ^The source database is read-locked only while it is being read;
! 6282: ** it is not locked continuously for the entire backup operation.
! 6283: ** ^Thus, the backup may be performed on a live source database without
! 6284: ** preventing other database connections from
! 6285: ** reading or writing to the source database while the backup is underway.
! 6286: **
! 6287: ** ^(To perform a backup operation:
! 6288: ** <ol>
! 6289: ** <li><b>sqlite3_backup_init()</b> is called once to initialize the
! 6290: ** backup,
! 6291: ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer
! 6292: ** the data between the two databases, and finally
! 6293: ** <li><b>sqlite3_backup_finish()</b> is called to release all resources
! 6294: ** associated with the backup operation.
! 6295: ** </ol>)^
! 6296: ** There should be exactly one call to sqlite3_backup_finish() for each
! 6297: ** successful call to sqlite3_backup_init().
! 6298: **
! 6299: ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>
! 6300: **
! 6301: ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the
! 6302: ** [database connection] associated with the destination database
! 6303: ** and the database name, respectively.
! 6304: ** ^The database name is "main" for the main database, "temp" for the
! 6305: ** temporary database, or the name specified after the AS keyword in
! 6306: ** an [ATTACH] statement for an attached database.
! 6307: ** ^The S and M arguments passed to
! 6308: ** sqlite3_backup_init(D,N,S,M) identify the [database connection]
! 6309: ** and database name of the source database, respectively.
! 6310: ** ^The source and destination [database connections] (parameters S and D)
! 6311: ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with
! 6312: ** an error.
! 6313: **
! 6314: ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is
! 6315: ** returned and an error code and error message are stored in the
! 6316: ** destination [database connection] D.
! 6317: ** ^The error code and message for the failed call to sqlite3_backup_init()
! 6318: ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or
! 6319: ** [sqlite3_errmsg16()] functions.
! 6320: ** ^A successful call to sqlite3_backup_init() returns a pointer to an
! 6321: ** [sqlite3_backup] object.
! 6322: ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and
! 6323: ** sqlite3_backup_finish() functions to perform the specified backup
! 6324: ** operation.
! 6325: **
! 6326: ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>
! 6327: **
! 6328: ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between
! 6329: ** the source and destination databases specified by [sqlite3_backup] object B.
! 6330: ** ^If N is negative, all remaining source pages are copied.
! 6331: ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there
! 6332: ** are still more pages to be copied, then the function returns [SQLITE_OK].
! 6333: ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages
! 6334: ** from source to destination, then it returns [SQLITE_DONE].
! 6335: ** ^If an error occurs while running sqlite3_backup_step(B,N),
! 6336: ** then an [error code] is returned. ^As well as [SQLITE_OK] and
! 6337: ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],
! 6338: ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an
! 6339: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.
! 6340: **
! 6341: ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if
! 6342: ** <ol>
! 6343: ** <li> the destination database was opened read-only, or
! 6344: ** <li> the destination database is using write-ahead-log journaling
! 6345: ** and the destination and source page sizes differ, or
! 6346: ** <li> the destination database is an in-memory database and the
! 6347: ** destination and source page sizes differ.
! 6348: ** </ol>)^
! 6349: **
! 6350: ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then
! 6351: ** the [sqlite3_busy_handler | busy-handler function]
! 6352: ** is invoked (if one is specified). ^If the
! 6353: ** busy-handler returns non-zero before the lock is available, then
! 6354: ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to
! 6355: ** sqlite3_backup_step() can be retried later. ^If the source
! 6356: ** [database connection]
! 6357: ** is being used to write to the source database when sqlite3_backup_step()
! 6358: ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this
! 6359: ** case the call to sqlite3_backup_step() can be retried later on. ^(If
! 6360: ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or
! 6361: ** [SQLITE_READONLY] is returned, then
! 6362: ** there is no point in retrying the call to sqlite3_backup_step(). These
! 6363: ** errors are considered fatal.)^ The application must accept
! 6364: ** that the backup operation has failed and pass the backup operation handle
! 6365: ** to the sqlite3_backup_finish() to release associated resources.
! 6366: **
! 6367: ** ^The first call to sqlite3_backup_step() obtains an exclusive lock
! 6368: ** on the destination file. ^The exclusive lock is not released until either
! 6369: ** sqlite3_backup_finish() is called or the backup operation is complete
! 6370: ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to
! 6371: ** sqlite3_backup_step() obtains a [shared lock] on the source database that
! 6372: ** lasts for the duration of the sqlite3_backup_step() call.
! 6373: ** ^Because the source database is not locked between calls to
! 6374: ** sqlite3_backup_step(), the source database may be modified mid-way
! 6375: ** through the backup process. ^If the source database is modified by an
! 6376: ** external process or via a database connection other than the one being
! 6377: ** used by the backup operation, then the backup will be automatically
! 6378: ** restarted by the next call to sqlite3_backup_step(). ^If the source
! 6379: ** database is modified by the using the same database connection as is used
! 6380: ** by the backup operation, then the backup database is automatically
! 6381: ** updated at the same time.
! 6382: **
! 6383: ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>
! 6384: **
! 6385: ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the
! 6386: ** application wishes to abandon the backup operation, the application
! 6387: ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().
! 6388: ** ^The sqlite3_backup_finish() interfaces releases all
! 6389: ** resources associated with the [sqlite3_backup] object.
! 6390: ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any
! 6391: ** active write-transaction on the destination database is rolled back.
! 6392: ** The [sqlite3_backup] object is invalid
! 6393: ** and may not be used following a call to sqlite3_backup_finish().
! 6394: **
! 6395: ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no
! 6396: ** sqlite3_backup_step() errors occurred, regardless or whether or not
! 6397: ** sqlite3_backup_step() completed.
! 6398: ** ^If an out-of-memory condition or IO error occurred during any prior
! 6399: ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then
! 6400: ** sqlite3_backup_finish() returns the corresponding [error code].
! 6401: **
! 6402: ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()
! 6403: ** is not a permanent error and does not affect the return value of
! 6404: ** sqlite3_backup_finish().
! 6405: **
! 6406: ** [[sqlite3_backup__remaining()]] [[sqlite3_backup_pagecount()]]
! 6407: ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>
! 6408: **
! 6409: ** ^Each call to sqlite3_backup_step() sets two values inside
! 6410: ** the [sqlite3_backup] object: the number of pages still to be backed
! 6411: ** up and the total number of pages in the source database file.
! 6412: ** The sqlite3_backup_remaining() and sqlite3_backup_pagecount() interfaces
! 6413: ** retrieve these two values, respectively.
! 6414: **
! 6415: ** ^The values returned by these functions are only updated by
! 6416: ** sqlite3_backup_step(). ^If the source database is modified during a backup
! 6417: ** operation, then the values are not updated to account for any extra
! 6418: ** pages that need to be updated or the size of the source database file
! 6419: ** changing.
! 6420: **
! 6421: ** <b>Concurrent Usage of Database Handles</b>
! 6422: **
! 6423: ** ^The source [database connection] may be used by the application for other
! 6424: ** purposes while a backup operation is underway or being initialized.
! 6425: ** ^If SQLite is compiled and configured to support threadsafe database
! 6426: ** connections, then the source database connection may be used concurrently
! 6427: ** from within other threads.
! 6428: **
! 6429: ** However, the application must guarantee that the destination
! 6430: ** [database connection] is not passed to any other API (by any thread) after
! 6431: ** sqlite3_backup_init() is called and before the corresponding call to
! 6432: ** sqlite3_backup_finish(). SQLite does not currently check to see
! 6433: ** if the application incorrectly accesses the destination [database connection]
! 6434: ** and so no error code is reported, but the operations may malfunction
! 6435: ** nevertheless. Use of the destination database connection while a
! 6436: ** backup is in progress might also also cause a mutex deadlock.
! 6437: **
! 6438: ** If running in [shared cache mode], the application must
! 6439: ** guarantee that the shared cache used by the destination database
! 6440: ** is not accessed while the backup is running. In practice this means
! 6441: ** that the application must guarantee that the disk file being
! 6442: ** backed up to is not accessed by any connection within the process,
! 6443: ** not just the specific connection that was passed to sqlite3_backup_init().
! 6444: **
! 6445: ** The [sqlite3_backup] object itself is partially threadsafe. Multiple
! 6446: ** threads may safely make multiple concurrent calls to sqlite3_backup_step().
! 6447: ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()
! 6448: ** APIs are not strictly speaking threadsafe. If they are invoked at the
! 6449: ** same time as another thread is invoking sqlite3_backup_step() it is
! 6450: ** possible that they return invalid values.
! 6451: */
! 6452: SQLITE_API sqlite3_backup *sqlite3_backup_init(
! 6453: sqlite3 *pDest, /* Destination database handle */
! 6454: const char *zDestName, /* Destination database name */
! 6455: sqlite3 *pSource, /* Source database handle */
! 6456: const char *zSourceName /* Source database name */
! 6457: );
! 6458: SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage);
! 6459: SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p);
! 6460: SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p);
! 6461: SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p);
! 6462:
! 6463: /*
! 6464: ** CAPI3REF: Unlock Notification
! 6465: **
! 6466: ** ^When running in shared-cache mode, a database operation may fail with
! 6467: ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or
! 6468: ** individual tables within the shared-cache cannot be obtained. See
! 6469: ** [SQLite Shared-Cache Mode] for a description of shared-cache locking.
! 6470: ** ^This API may be used to register a callback that SQLite will invoke
! 6471: ** when the connection currently holding the required lock relinquishes it.
! 6472: ** ^This API is only available if the library was compiled with the
! 6473: ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.
! 6474: **
! 6475: ** See Also: [Using the SQLite Unlock Notification Feature].
! 6476: **
! 6477: ** ^Shared-cache locks are released when a database connection concludes
! 6478: ** its current transaction, either by committing it or rolling it back.
! 6479: **
! 6480: ** ^When a connection (known as the blocked connection) fails to obtain a
! 6481: ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the
! 6482: ** identity of the database connection (the blocking connection) that
! 6483: ** has locked the required resource is stored internally. ^After an
! 6484: ** application receives an SQLITE_LOCKED error, it may call the
! 6485: ** sqlite3_unlock_notify() method with the blocked connection handle as
! 6486: ** the first argument to register for a callback that will be invoked
! 6487: ** when the blocking connections current transaction is concluded. ^The
! 6488: ** callback is invoked from within the [sqlite3_step] or [sqlite3_close]
! 6489: ** call that concludes the blocking connections transaction.
! 6490: **
! 6491: ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,
! 6492: ** there is a chance that the blocking connection will have already
! 6493: ** concluded its transaction by the time sqlite3_unlock_notify() is invoked.
! 6494: ** If this happens, then the specified callback is invoked immediately,
! 6495: ** from within the call to sqlite3_unlock_notify().)^
! 6496: **
! 6497: ** ^If the blocked connection is attempting to obtain a write-lock on a
! 6498: ** shared-cache table, and more than one other connection currently holds
! 6499: ** a read-lock on the same table, then SQLite arbitrarily selects one of
! 6500: ** the other connections to use as the blocking connection.
! 6501: **
! 6502: ** ^(There may be at most one unlock-notify callback registered by a
! 6503: ** blocked connection. If sqlite3_unlock_notify() is called when the
! 6504: ** blocked connection already has a registered unlock-notify callback,
! 6505: ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is
! 6506: ** called with a NULL pointer as its second argument, then any existing
! 6507: ** unlock-notify callback is canceled. ^The blocked connections
! 6508: ** unlock-notify callback may also be canceled by closing the blocked
! 6509: ** connection using [sqlite3_close()].
! 6510: **
! 6511: ** The unlock-notify callback is not reentrant. If an application invokes
! 6512: ** any sqlite3_xxx API functions from within an unlock-notify callback, a
! 6513: ** crash or deadlock may be the result.
! 6514: **
! 6515: ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always
! 6516: ** returns SQLITE_OK.
! 6517: **
! 6518: ** <b>Callback Invocation Details</b>
! 6519: **
! 6520: ** When an unlock-notify callback is registered, the application provides a
! 6521: ** single void* pointer that is passed to the callback when it is invoked.
! 6522: ** However, the signature of the callback function allows SQLite to pass
! 6523: ** it an array of void* context pointers. The first argument passed to
! 6524: ** an unlock-notify callback is a pointer to an array of void* pointers,
! 6525: ** and the second is the number of entries in the array.
! 6526: **
! 6527: ** When a blocking connections transaction is concluded, there may be
! 6528: ** more than one blocked connection that has registered for an unlock-notify
! 6529: ** callback. ^If two or more such blocked connections have specified the
! 6530: ** same callback function, then instead of invoking the callback function
! 6531: ** multiple times, it is invoked once with the set of void* context pointers
! 6532: ** specified by the blocked connections bundled together into an array.
! 6533: ** This gives the application an opportunity to prioritize any actions
! 6534: ** related to the set of unblocked database connections.
! 6535: **
! 6536: ** <b>Deadlock Detection</b>
! 6537: **
! 6538: ** Assuming that after registering for an unlock-notify callback a
! 6539: ** database waits for the callback to be issued before taking any further
! 6540: ** action (a reasonable assumption), then using this API may cause the
! 6541: ** application to deadlock. For example, if connection X is waiting for
! 6542: ** connection Y's transaction to be concluded, and similarly connection
! 6543: ** Y is waiting on connection X's transaction, then neither connection
! 6544: ** will proceed and the system may remain deadlocked indefinitely.
! 6545: **
! 6546: ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock
! 6547: ** detection. ^If a given call to sqlite3_unlock_notify() would put the
! 6548: ** system in a deadlocked state, then SQLITE_LOCKED is returned and no
! 6549: ** unlock-notify callback is registered. The system is said to be in
! 6550: ** a deadlocked state if connection A has registered for an unlock-notify
! 6551: ** callback on the conclusion of connection B's transaction, and connection
! 6552: ** B has itself registered for an unlock-notify callback when connection
! 6553: ** A's transaction is concluded. ^Indirect deadlock is also detected, so
! 6554: ** the system is also considered to be deadlocked if connection B has
! 6555: ** registered for an unlock-notify callback on the conclusion of connection
! 6556: ** C's transaction, where connection C is waiting on connection A. ^Any
! 6557: ** number of levels of indirection are allowed.
! 6558: **
! 6559: ** <b>The "DROP TABLE" Exception</b>
! 6560: **
! 6561: ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost
! 6562: ** always appropriate to call sqlite3_unlock_notify(). There is however,
! 6563: ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,
! 6564: ** SQLite checks if there are any currently executing SELECT statements
! 6565: ** that belong to the same connection. If there are, SQLITE_LOCKED is
! 6566: ** returned. In this case there is no "blocking connection", so invoking
! 6567: ** sqlite3_unlock_notify() results in the unlock-notify callback being
! 6568: ** invoked immediately. If the application then re-attempts the "DROP TABLE"
! 6569: ** or "DROP INDEX" query, an infinite loop might be the result.
! 6570: **
! 6571: ** One way around this problem is to check the extended error code returned
! 6572: ** by an sqlite3_step() call. ^(If there is a blocking connection, then the
! 6573: ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in
! 6574: ** the special "DROP TABLE/INDEX" case, the extended error code is just
! 6575: ** SQLITE_LOCKED.)^
! 6576: */
! 6577: SQLITE_API int sqlite3_unlock_notify(
! 6578: sqlite3 *pBlocked, /* Waiting connection */
! 6579: void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */
! 6580: void *pNotifyArg /* Argument to pass to xNotify */
! 6581: );
! 6582:
! 6583:
! 6584: /*
! 6585: ** CAPI3REF: String Comparison
! 6586: **
! 6587: ** ^The [sqlite3_strnicmp()] API allows applications and extensions to
! 6588: ** compare the contents of two buffers containing UTF-8 strings in a
! 6589: ** case-independent fashion, using the same definition of case independence
! 6590: ** that SQLite uses internally when comparing identifiers.
! 6591: */
! 6592: SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
! 6593:
! 6594: /*
! 6595: ** CAPI3REF: Error Logging Interface
! 6596: **
! 6597: ** ^The [sqlite3_log()] interface writes a message into the error log
! 6598: ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
! 6599: ** ^If logging is enabled, the zFormat string and subsequent arguments are
! 6600: ** used with [sqlite3_snprintf()] to generate the final output string.
! 6601: **
! 6602: ** The sqlite3_log() interface is intended for use by extensions such as
! 6603: ** virtual tables, collating functions, and SQL functions. While there is
! 6604: ** nothing to prevent an application from calling sqlite3_log(), doing so
! 6605: ** is considered bad form.
! 6606: **
! 6607: ** The zFormat string must not be NULL.
! 6608: **
! 6609: ** To avoid deadlocks and other threading problems, the sqlite3_log() routine
! 6610: ** will not use dynamically allocated memory. The log message is stored in
! 6611: ** a fixed-length buffer on the stack. If the log message is longer than
! 6612: ** a few hundred characters, it will be truncated to the length of the
! 6613: ** buffer.
! 6614: */
! 6615: SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...);
! 6616:
! 6617: /*
! 6618: ** CAPI3REF: Write-Ahead Log Commit Hook
! 6619: **
! 6620: ** ^The [sqlite3_wal_hook()] function is used to register a callback that
! 6621: ** will be invoked each time a database connection commits data to a
! 6622: ** [write-ahead log] (i.e. whenever a transaction is committed in
! 6623: ** [journal_mode | journal_mode=WAL mode]).
! 6624: **
! 6625: ** ^The callback is invoked by SQLite after the commit has taken place and
! 6626: ** the associated write-lock on the database released, so the implementation
! 6627: ** may read, write or [checkpoint] the database as required.
! 6628: **
! 6629: ** ^The first parameter passed to the callback function when it is invoked
! 6630: ** is a copy of the third parameter passed to sqlite3_wal_hook() when
! 6631: ** registering the callback. ^The second is a copy of the database handle.
! 6632: ** ^The third parameter is the name of the database that was written to -
! 6633: ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter
! 6634: ** is the number of pages currently in the write-ahead log file,
! 6635: ** including those that were just committed.
! 6636: **
! 6637: ** The callback function should normally return [SQLITE_OK]. ^If an error
! 6638: ** code is returned, that error will propagate back up through the
! 6639: ** SQLite code base to cause the statement that provoked the callback
! 6640: ** to report an error, though the commit will have still occurred. If the
! 6641: ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value
! 6642: ** that does not correspond to any valid SQLite error code, the results
! 6643: ** are undefined.
! 6644: **
! 6645: ** A single database handle may have at most a single write-ahead log callback
! 6646: ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any
! 6647: ** previously registered write-ahead log callback. ^Note that the
! 6648: ** [sqlite3_wal_autocheckpoint()] interface and the
! 6649: ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will
! 6650: ** those overwrite any prior [sqlite3_wal_hook()] settings.
! 6651: */
! 6652: SQLITE_API void *sqlite3_wal_hook(
! 6653: sqlite3*,
! 6654: int(*)(void *,sqlite3*,const char*,int),
! 6655: void*
! 6656: );
! 6657:
! 6658: /*
! 6659: ** CAPI3REF: Configure an auto-checkpoint
! 6660: **
! 6661: ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around
! 6662: ** [sqlite3_wal_hook()] that causes any database on [database connection] D
! 6663: ** to automatically [checkpoint]
! 6664: ** after committing a transaction if there are N or
! 6665: ** more frames in the [write-ahead log] file. ^Passing zero or
! 6666: ** a negative value as the nFrame parameter disables automatic
! 6667: ** checkpoints entirely.
! 6668: **
! 6669: ** ^The callback registered by this function replaces any existing callback
! 6670: ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback
! 6671: ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism
! 6672: ** configured by this function.
! 6673: **
! 6674: ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface
! 6675: ** from SQL.
! 6676: **
! 6677: ** ^Every new [database connection] defaults to having the auto-checkpoint
! 6678: ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]
! 6679: ** pages. The use of this interface
! 6680: ** is only necessary if the default setting is found to be suboptimal
! 6681: ** for a particular application.
! 6682: */
! 6683: SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N);
! 6684:
! 6685: /*
! 6686: ** CAPI3REF: Checkpoint a database
! 6687: **
! 6688: ** ^The [sqlite3_wal_checkpoint(D,X)] interface causes database named X
! 6689: ** on [database connection] D to be [checkpointed]. ^If X is NULL or an
! 6690: ** empty string, then a checkpoint is run on all databases of
! 6691: ** connection D. ^If the database connection D is not in
! 6692: ** [WAL | write-ahead log mode] then this interface is a harmless no-op.
! 6693: **
! 6694: ** ^The [wal_checkpoint pragma] can be used to invoke this interface
! 6695: ** from SQL. ^The [sqlite3_wal_autocheckpoint()] interface and the
! 6696: ** [wal_autocheckpoint pragma] can be used to cause this interface to be
! 6697: ** run whenever the WAL reaches a certain size threshold.
! 6698: **
! 6699: ** See also: [sqlite3_wal_checkpoint_v2()]
! 6700: */
! 6701: SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb);
! 6702:
! 6703: /*
! 6704: ** CAPI3REF: Checkpoint a database
! 6705: **
! 6706: ** Run a checkpoint operation on WAL database zDb attached to database
! 6707: ** handle db. The specific operation is determined by the value of the
! 6708: ** eMode parameter:
! 6709: **
! 6710: ** <dl>
! 6711: ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>
! 6712: ** Checkpoint as many frames as possible without waiting for any database
! 6713: ** readers or writers to finish. Sync the db file if all frames in the log
! 6714: ** are checkpointed. This mode is the same as calling
! 6715: ** sqlite3_wal_checkpoint(). The busy-handler callback is never invoked.
! 6716: **
! 6717: ** <dt>SQLITE_CHECKPOINT_FULL<dd>
! 6718: ** This mode blocks (calls the busy-handler callback) until there is no
! 6719: ** database writer and all readers are reading from the most recent database
! 6720: ** snapshot. It then checkpoints all frames in the log file and syncs the
! 6721: ** database file. This call blocks database writers while it is running,
! 6722: ** but not database readers.
! 6723: **
! 6724: ** <dt>SQLITE_CHECKPOINT_RESTART<dd>
! 6725: ** This mode works the same way as SQLITE_CHECKPOINT_FULL, except after
! 6726: ** checkpointing the log file it blocks (calls the busy-handler callback)
! 6727: ** until all readers are reading from the database file only. This ensures
! 6728: ** that the next client to write to the database file restarts the log file
! 6729: ** from the beginning. This call blocks database writers while it is running,
! 6730: ** but not database readers.
! 6731: ** </dl>
! 6732: **
! 6733: ** If pnLog is not NULL, then *pnLog is set to the total number of frames in
! 6734: ** the log file before returning. If pnCkpt is not NULL, then *pnCkpt is set to
! 6735: ** the total number of checkpointed frames (including any that were already
! 6736: ** checkpointed when this function is called). *pnLog and *pnCkpt may be
! 6737: ** populated even if sqlite3_wal_checkpoint_v2() returns other than SQLITE_OK.
! 6738: ** If no values are available because of an error, they are both set to -1
! 6739: ** before returning to communicate this to the caller.
! 6740: **
! 6741: ** All calls obtain an exclusive "checkpoint" lock on the database file. If
! 6742: ** any other process is running a checkpoint operation at the same time, the
! 6743: ** lock cannot be obtained and SQLITE_BUSY is returned. Even if there is a
! 6744: ** busy-handler configured, it will not be invoked in this case.
! 6745: **
! 6746: ** The SQLITE_CHECKPOINT_FULL and RESTART modes also obtain the exclusive
! 6747: ** "writer" lock on the database file. If the writer lock cannot be obtained
! 6748: ** immediately, and a busy-handler is configured, it is invoked and the writer
! 6749: ** lock retried until either the busy-handler returns 0 or the lock is
! 6750: ** successfully obtained. The busy-handler is also invoked while waiting for
! 6751: ** database readers as described above. If the busy-handler returns 0 before
! 6752: ** the writer lock is obtained or while waiting for database readers, the
! 6753: ** checkpoint operation proceeds from that point in the same way as
! 6754: ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible
! 6755: ** without blocking any further. SQLITE_BUSY is returned in this case.
! 6756: **
! 6757: ** If parameter zDb is NULL or points to a zero length string, then the
! 6758: ** specified operation is attempted on all WAL databases. In this case the
! 6759: ** values written to output parameters *pnLog and *pnCkpt are undefined. If
! 6760: ** an SQLITE_BUSY error is encountered when processing one or more of the
! 6761: ** attached WAL databases, the operation is still attempted on any remaining
! 6762: ** attached databases and SQLITE_BUSY is returned to the caller. If any other
! 6763: ** error occurs while processing an attached database, processing is abandoned
! 6764: ** and the error code returned to the caller immediately. If no error
! 6765: ** (SQLITE_BUSY or otherwise) is encountered while processing the attached
! 6766: ** databases, SQLITE_OK is returned.
! 6767: **
! 6768: ** If database zDb is the name of an attached database that is not in WAL
! 6769: ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. If
! 6770: ** zDb is not NULL (or a zero length string) and is not the name of any
! 6771: ** attached database, SQLITE_ERROR is returned to the caller.
! 6772: */
! 6773: SQLITE_API int sqlite3_wal_checkpoint_v2(
! 6774: sqlite3 *db, /* Database handle */
! 6775: const char *zDb, /* Name of attached database (or NULL) */
! 6776: int eMode, /* SQLITE_CHECKPOINT_* value */
! 6777: int *pnLog, /* OUT: Size of WAL log in frames */
! 6778: int *pnCkpt /* OUT: Total number of frames checkpointed */
! 6779: );
! 6780:
! 6781: /*
! 6782: ** CAPI3REF: Checkpoint operation parameters
! 6783: **
! 6784: ** These constants can be used as the 3rd parameter to
! 6785: ** [sqlite3_wal_checkpoint_v2()]. See the [sqlite3_wal_checkpoint_v2()]
! 6786: ** documentation for additional information about the meaning and use of
! 6787: ** each of these values.
! 6788: */
! 6789: #define SQLITE_CHECKPOINT_PASSIVE 0
! 6790: #define SQLITE_CHECKPOINT_FULL 1
! 6791: #define SQLITE_CHECKPOINT_RESTART 2
! 6792:
! 6793: /*
! 6794: ** CAPI3REF: Virtual Table Interface Configuration
! 6795: **
! 6796: ** This function may be called by either the [xConnect] or [xCreate] method
! 6797: ** of a [virtual table] implementation to configure
! 6798: ** various facets of the virtual table interface.
! 6799: **
! 6800: ** If this interface is invoked outside the context of an xConnect or
! 6801: ** xCreate virtual table method then the behavior is undefined.
! 6802: **
! 6803: ** At present, there is only one option that may be configured using
! 6804: ** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options
! 6805: ** may be added in the future.
! 6806: */
! 6807: SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
! 6808:
! 6809: /*
! 6810: ** CAPI3REF: Virtual Table Configuration Options
! 6811: **
! 6812: ** These macros define the various options to the
! 6813: ** [sqlite3_vtab_config()] interface that [virtual table] implementations
! 6814: ** can use to customize and optimize their behavior.
! 6815: **
! 6816: ** <dl>
! 6817: ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT
! 6818: ** <dd>Calls of the form
! 6819: ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,
! 6820: ** where X is an integer. If X is zero, then the [virtual table] whose
! 6821: ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not
! 6822: ** support constraints. In this configuration (which is the default) if
! 6823: ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire
! 6824: ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been
! 6825: ** specified as part of the users SQL statement, regardless of the actual
! 6826: ** ON CONFLICT mode specified.
! 6827: **
! 6828: ** If X is non-zero, then the virtual table implementation guarantees
! 6829: ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before
! 6830: ** any modifications to internal or persistent data structures have been made.
! 6831: ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite
! 6832: ** is able to roll back a statement or database transaction, and abandon
! 6833: ** or continue processing the current SQL statement as appropriate.
! 6834: ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns
! 6835: ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode
! 6836: ** had been ABORT.
! 6837: **
! 6838: ** Virtual table implementations that are required to handle OR REPLACE
! 6839: ** must do so within the [xUpdate] method. If a call to the
! 6840: ** [sqlite3_vtab_on_conflict()] function indicates that the current ON
! 6841: ** CONFLICT policy is REPLACE, the virtual table implementation should
! 6842: ** silently replace the appropriate rows within the xUpdate callback and
! 6843: ** return SQLITE_OK. Or, if this is not possible, it may return
! 6844: ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT
! 6845: ** constraint handling.
! 6846: ** </dl>
! 6847: */
! 6848: #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
! 6849:
! 6850: /*
! 6851: ** CAPI3REF: Determine The Virtual Table Conflict Policy
! 6852: **
! 6853: ** This function may only be called from within a call to the [xUpdate] method
! 6854: ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The
! 6855: ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],
! 6856: ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode
! 6857: ** of the SQL statement that triggered the call to the [xUpdate] method of the
! 6858: ** [virtual table].
! 6859: */
! 6860: SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
! 6861:
! 6862: /*
! 6863: ** CAPI3REF: Conflict resolution modes
! 6864: **
! 6865: ** These constants are returned by [sqlite3_vtab_on_conflict()] to
! 6866: ** inform a [virtual table] implementation what the [ON CONFLICT] mode
! 6867: ** is for the SQL statement being evaluated.
! 6868: **
! 6869: ** Note that the [SQLITE_IGNORE] constant is also used as a potential
! 6870: ** return value from the [sqlite3_set_authorizer()] callback and that
! 6871: ** [SQLITE_ABORT] is also a [result code].
! 6872: */
! 6873: #define SQLITE_ROLLBACK 1
! 6874: /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */
! 6875: #define SQLITE_FAIL 3
! 6876: /* #define SQLITE_ABORT 4 // Also an error code */
! 6877: #define SQLITE_REPLACE 5
! 6878:
! 6879:
! 6880:
! 6881: /*
! 6882: ** Undo the hack that converts floating point types to integer for
! 6883: ** builds on processors without floating point support.
! 6884: */
! 6885: #ifdef SQLITE_OMIT_FLOATING_POINT
! 6886: # undef double
! 6887: #endif
! 6888:
! 6889: #ifdef __cplusplus
! 6890: } /* End of the 'extern "C"' block */
! 6891: #endif
! 6892: #endif
! 6893:
! 6894: /*
! 6895: ** 2010 August 30
! 6896: **
! 6897: ** The author disclaims copyright to this source code. In place of
! 6898: ** a legal notice, here is a blessing:
! 6899: **
! 6900: ** May you do good and not evil.
! 6901: ** May you find forgiveness for yourself and forgive others.
! 6902: ** May you share freely, never taking more than you give.
! 6903: **
! 6904: *************************************************************************
! 6905: */
! 6906:
! 6907: #ifndef _SQLITE3RTREE_H_
! 6908: #define _SQLITE3RTREE_H_
! 6909:
! 6910:
! 6911: #ifdef __cplusplus
! 6912: extern "C" {
! 6913: #endif
! 6914:
! 6915: typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry;
! 6916:
! 6917: /*
! 6918: ** Register a geometry callback named zGeom that can be used as part of an
! 6919: ** R-Tree geometry query as follows:
! 6920: **
! 6921: ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)
! 6922: */
! 6923: SQLITE_API int sqlite3_rtree_geometry_callback(
! 6924: sqlite3 *db,
! 6925: const char *zGeom,
! 6926: int (*xGeom)(sqlite3_rtree_geometry *, int nCoord, double *aCoord, int *pRes),
! 6927: void *pContext
! 6928: );
! 6929:
! 6930:
! 6931: /*
! 6932: ** A pointer to a structure of the following type is passed as the first
! 6933: ** argument to callbacks registered using rtree_geometry_callback().
! 6934: */
! 6935: struct sqlite3_rtree_geometry {
! 6936: void *pContext; /* Copy of pContext passed to s_r_g_c() */
! 6937: int nParam; /* Size of array aParam[] */
! 6938: double *aParam; /* Parameters passed to SQL geom function */
! 6939: void *pUser; /* Callback implementation user data */
! 6940: void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */
! 6941: };
! 6942:
! 6943:
! 6944: #ifdef __cplusplus
! 6945: } /* end of the 'extern "C"' block */
! 6946: #endif
! 6947:
! 6948: #endif /* ifndef _SQLITE3RTREE_H_ */
! 6949:
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