Return to sqlite3.h CVS log | Up to [ELWIX - Embedded LightWeight unIX -] / elwix / files / sqlite / dist |
1.2 ! 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: