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 supposed 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 ** Provide the ability to override linkage features of the interface. 47 */ 48 #ifndef SQLITE_EXTERN 49 # define SQLITE_EXTERN extern 50 #endif 51 #ifndef SQLITE_API 52 # define SQLITE_API 53 #endif 54 #ifndef SQLITE_CDECL 55 # define SQLITE_CDECL 56 #endif 57 #ifndef SQLITE_STDCALL 58 # define SQLITE_STDCALL 59 #endif 60 61 /* 62 ** These no-op macros are used in front of interfaces to mark those 63 ** interfaces as either deprecated or experimental. New applications 64 ** should not use deprecated interfaces - they are supported for backwards 65 ** compatibility only. Application writers should be aware that 66 ** experimental interfaces are subject to change in point releases. 67 ** 68 ** These macros used to resolve to various kinds of compiler magic that 69 ** would generate warning messages when they were used. But that 70 ** compiler magic ended up generating such a flurry of bug reports 71 ** that we have taken it all out and gone back to using simple 72 ** noop macros. 73 */ 74 #define SQLITE_DEPRECATED 75 #define SQLITE_EXPERIMENTAL 76 77 /* 78 ** Ensure these symbols were not defined by some previous header file. 79 */ 80 #ifdef SQLITE_VERSION 81 # undef SQLITE_VERSION 82 #endif 83 #ifdef SQLITE_VERSION_NUMBER 84 # undef SQLITE_VERSION_NUMBER 85 #endif 86 87 /* 88 ** CAPI3REF: Compile-Time Library Version Numbers 89 ** 90 ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header 91 ** evaluates to a string literal that is the SQLite version in the 92 ** format "X.Y.Z" where X is the major version number (always 3 for 93 ** SQLite3) and Y is the minor version number and Z is the release number.)^ 94 ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer 95 ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same 96 ** numbers used in [SQLITE_VERSION].)^ 97 ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also 98 ** be larger than the release from which it is derived. Either Y will 99 ** be held constant and Z will be incremented or else Y will be incremented 100 ** and Z will be reset to zero. 101 ** 102 ** Since version 3.6.18, SQLite source code has been stored in the 103 ** <a href="http://www.fossil-scm.org/">Fossil configuration management 104 ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to 105 ** a string which identifies a particular check-in of SQLite 106 ** within its configuration management system. ^The SQLITE_SOURCE_ID 107 ** string contains the date and time of the check-in (UTC) and an SHA1 108 ** hash of the entire source tree. 109 ** 110 ** See also: [sqlite3_libversion()], 111 ** [sqlite3_libversion_number()], [sqlite3_sourceid()], 112 ** [sqlite_version()] and [sqlite_source_id()]. 113 */ 114 #define SQLITE_VERSION "3.9.2" 115 #define SQLITE_VERSION_NUMBER 3009002 116 #define SQLITE_SOURCE_ID "2015-11-02 18:31:45 bda77dda9697c463c3d0704014d51627fceee328" 117 118 /* 119 ** CAPI3REF: Run-Time Library Version Numbers 120 ** KEYWORDS: sqlite3_version, sqlite3_sourceid 121 ** 122 ** These interfaces provide the same information as the [SQLITE_VERSION], 123 ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros 124 ** but are associated with the library instead of the header file. ^(Cautious 125 ** programmers might include assert() statements in their application to 126 ** verify that values returned by these interfaces match the macros in 127 ** the header, and thus ensure that the application is 128 ** compiled with matching library and header files. 129 ** 130 ** <blockquote><pre> 131 ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); 132 ** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 ); 133 ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); 134 ** </pre></blockquote>)^ 135 ** 136 ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] 137 ** macro. ^The sqlite3_libversion() function returns a pointer to the 138 ** to the sqlite3_version[] string constant. The sqlite3_libversion() 139 ** function is provided for use in DLLs since DLL users usually do not have 140 ** direct access to string constants within the DLL. ^The 141 ** sqlite3_libversion_number() function returns an integer equal to 142 ** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns 143 ** a pointer to a string constant whose value is the same as the 144 ** [SQLITE_SOURCE_ID] C preprocessor macro. 145 ** 146 ** See also: [sqlite_version()] and [sqlite_source_id()]. 147 */ 148 SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; 149 SQLITE_API const char *SQLITE_STDCALL sqlite3_libversion(void); 150 SQLITE_API const char *SQLITE_STDCALL sqlite3_sourceid(void); 151 SQLITE_API int SQLITE_STDCALL sqlite3_libversion_number(void); 152 153 /* 154 ** CAPI3REF: Run-Time Library Compilation Options Diagnostics 155 ** 156 ** ^The sqlite3_compileoption_used() function returns 0 or 1 157 ** indicating whether the specified option was defined at 158 ** compile time. ^The SQLITE_ prefix may be omitted from the 159 ** option name passed to sqlite3_compileoption_used(). 160 ** 161 ** ^The sqlite3_compileoption_get() function allows iterating 162 ** over the list of options that were defined at compile time by 163 ** returning the N-th compile time option string. ^If N is out of range, 164 ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ 165 ** prefix is omitted from any strings returned by 166 ** sqlite3_compileoption_get(). 167 ** 168 ** ^Support for the diagnostic functions sqlite3_compileoption_used() 169 ** and sqlite3_compileoption_get() may be omitted by specifying the 170 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. 171 ** 172 ** See also: SQL functions [sqlite_compileoption_used()] and 173 ** [sqlite_compileoption_get()] and the [compile_options pragma]. 174 */ 175 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 176 SQLITE_API int SQLITE_STDCALL sqlite3_compileoption_used(const char *zOptName); 177 SQLITE_API const char *SQLITE_STDCALL sqlite3_compileoption_get(int N); 178 #endif 179 180 /* 181 ** CAPI3REF: Test To See If The Library Is Threadsafe 182 ** 183 ** ^The sqlite3_threadsafe() function returns zero if and only if 184 ** SQLite was compiled with mutexing code omitted due to the 185 ** [SQLITE_THREADSAFE] compile-time option being set to 0. 186 ** 187 ** SQLite can be compiled with or without mutexes. When 188 ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes 189 ** are enabled and SQLite is threadsafe. When the 190 ** [SQLITE_THREADSAFE] macro is 0, 191 ** the mutexes are omitted. Without the mutexes, it is not safe 192 ** to use SQLite concurrently from more than one thread. 193 ** 194 ** Enabling mutexes incurs a measurable performance penalty. 195 ** So if speed is of utmost importance, it makes sense to disable 196 ** the mutexes. But for maximum safety, mutexes should be enabled. 197 ** ^The default behavior is for mutexes to be enabled. 198 ** 199 ** This interface can be used by an application to make sure that the 200 ** version of SQLite that it is linking against was compiled with 201 ** the desired setting of the [SQLITE_THREADSAFE] macro. 202 ** 203 ** This interface only reports on the compile-time mutex setting 204 ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with 205 ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but 206 ** can be fully or partially disabled using a call to [sqlite3_config()] 207 ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], 208 ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the 209 ** sqlite3_threadsafe() function shows only the compile-time setting of 210 ** thread safety, not any run-time changes to that setting made by 211 ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() 212 ** is unchanged by calls to sqlite3_config().)^ 213 ** 214 ** See the [threading mode] documentation for additional information. 215 */ 216 SQLITE_API int SQLITE_STDCALL sqlite3_threadsafe(void); 217 218 /* 219 ** CAPI3REF: Database Connection Handle 220 ** KEYWORDS: {database connection} {database connections} 221 ** 222 ** Each open SQLite database is represented by a pointer to an instance of 223 ** the opaque structure named "sqlite3". It is useful to think of an sqlite3 224 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and 225 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] 226 ** and [sqlite3_close_v2()] are its destructors. There are many other 227 ** interfaces (such as 228 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and 229 ** [sqlite3_busy_timeout()] to name but three) that are methods on an 230 ** sqlite3 object. 231 */ 232 typedef struct sqlite3 sqlite3; 233 234 /* 235 ** CAPI3REF: 64-Bit Integer Types 236 ** KEYWORDS: sqlite_int64 sqlite_uint64 237 ** 238 ** Because there is no cross-platform way to specify 64-bit integer types 239 ** SQLite includes typedefs for 64-bit signed and unsigned integers. 240 ** 241 ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. 242 ** The sqlite_int64 and sqlite_uint64 types are supported for backwards 243 ** compatibility only. 244 ** 245 ** ^The sqlite3_int64 and sqlite_int64 types can store integer values 246 ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The 247 ** sqlite3_uint64 and sqlite_uint64 types can store integer values 248 ** between 0 and +18446744073709551615 inclusive. 249 */ 250 #ifdef SQLITE_INT64_TYPE 251 typedef SQLITE_INT64_TYPE sqlite_int64; 252 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; 253 #elif defined(_MSC_VER) || defined(__BORLANDC__) 254 typedef __int64 sqlite_int64; 255 typedef unsigned __int64 sqlite_uint64; 256 #else 257 typedef long long int sqlite_int64; 258 typedef unsigned long long int sqlite_uint64; 259 #endif 260 typedef sqlite_int64 sqlite3_int64; 261 typedef sqlite_uint64 sqlite3_uint64; 262 263 /* 264 ** If compiling for a processor that lacks floating point support, 265 ** substitute integer for floating-point. 266 */ 267 #ifdef SQLITE_OMIT_FLOATING_POINT 268 # define double sqlite3_int64 269 #endif 270 271 /* 272 ** CAPI3REF: Closing A Database Connection 273 ** DESTRUCTOR: sqlite3 274 ** 275 ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors 276 ** for the [sqlite3] object. 277 ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if 278 ** the [sqlite3] object is successfully destroyed and all associated 279 ** resources are deallocated. 280 ** 281 ** ^If the database connection is associated with unfinalized prepared 282 ** statements or unfinished sqlite3_backup objects then sqlite3_close() 283 ** will leave the database connection open and return [SQLITE_BUSY]. 284 ** ^If sqlite3_close_v2() is called with unfinalized prepared statements 285 ** and/or unfinished sqlite3_backups, then the database connection becomes 286 ** an unusable "zombie" which will automatically be deallocated when the 287 ** last prepared statement is finalized or the last sqlite3_backup is 288 ** finished. The sqlite3_close_v2() interface is intended for use with 289 ** host languages that are garbage collected, and where the order in which 290 ** destructors are called is arbitrary. 291 ** 292 ** Applications should [sqlite3_finalize | finalize] all [prepared statements], 293 ** [sqlite3_blob_close | close] all [BLOB handles], and 294 ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated 295 ** with the [sqlite3] object prior to attempting to close the object. ^If 296 ** sqlite3_close_v2() is called on a [database connection] that still has 297 ** outstanding [prepared statements], [BLOB handles], and/or 298 ** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation 299 ** of resources is deferred until all [prepared statements], [BLOB handles], 300 ** and [sqlite3_backup] objects are also destroyed. 301 ** 302 ** ^If an [sqlite3] object is destroyed while a transaction is open, 303 ** the transaction is automatically rolled back. 304 ** 305 ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] 306 ** must be either a NULL 307 ** pointer or an [sqlite3] object pointer obtained 308 ** from [sqlite3_open()], [sqlite3_open16()], or 309 ** [sqlite3_open_v2()], and not previously closed. 310 ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer 311 ** argument is a harmless no-op. 312 */ 313 SQLITE_API int SQLITE_STDCALL sqlite3_close(sqlite3*); 314 SQLITE_API int SQLITE_STDCALL sqlite3_close_v2(sqlite3*); 315 316 /* 317 ** The type for a callback function. 318 ** This is legacy and deprecated. It is included for historical 319 ** compatibility and is not documented. 320 */ 321 typedef int (*sqlite3_callback)(void*,int,char**, char**); 322 323 /* 324 ** CAPI3REF: One-Step Query Execution Interface 325 ** METHOD: sqlite3 326 ** 327 ** The sqlite3_exec() interface is a convenience wrapper around 328 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], 329 ** that allows an application to run multiple statements of SQL 330 ** without having to use a lot of C code. 331 ** 332 ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, 333 ** semicolon-separate SQL statements passed into its 2nd argument, 334 ** in the context of the [database connection] passed in as its 1st 335 ** argument. ^If the callback function of the 3rd argument to 336 ** sqlite3_exec() is not NULL, then it is invoked for each result row 337 ** coming out of the evaluated SQL statements. ^The 4th argument to 338 ** sqlite3_exec() is relayed through to the 1st argument of each 339 ** callback invocation. ^If the callback pointer to sqlite3_exec() 340 ** is NULL, then no callback is ever invoked and result rows are 341 ** ignored. 342 ** 343 ** ^If an error occurs while evaluating the SQL statements passed into 344 ** sqlite3_exec(), then execution of the current statement stops and 345 ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() 346 ** is not NULL then any error message is written into memory obtained 347 ** from [sqlite3_malloc()] and passed back through the 5th parameter. 348 ** To avoid memory leaks, the application should invoke [sqlite3_free()] 349 ** on error message strings returned through the 5th parameter of 350 ** of sqlite3_exec() after the error message string is no longer needed. 351 ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors 352 ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to 353 ** NULL before returning. 354 ** 355 ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() 356 ** routine returns SQLITE_ABORT without invoking the callback again and 357 ** without running any subsequent SQL statements. 358 ** 359 ** ^The 2nd argument to the sqlite3_exec() callback function is the 360 ** number of columns in the result. ^The 3rd argument to the sqlite3_exec() 361 ** callback is an array of pointers to strings obtained as if from 362 ** [sqlite3_column_text()], one for each column. ^If an element of a 363 ** result row is NULL then the corresponding string pointer for the 364 ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the 365 ** sqlite3_exec() callback is an array of pointers to strings where each 366 ** entry represents the name of corresponding result column as obtained 367 ** from [sqlite3_column_name()]. 368 ** 369 ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer 370 ** to an empty string, or a pointer that contains only whitespace and/or 371 ** SQL comments, then no SQL statements are evaluated and the database 372 ** is not changed. 373 ** 374 ** Restrictions: 375 ** 376 ** <ul> 377 ** <li> The application must ensure that the 1st parameter to sqlite3_exec() 378 ** is a valid and open [database connection]. 379 ** <li> The application must not close the [database connection] specified by 380 ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. 381 ** <li> The application must not modify the SQL statement text passed into 382 ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. 383 ** </ul> 384 */ 385 SQLITE_API int SQLITE_STDCALL sqlite3_exec( 386 sqlite3*, /* An open database */ 387 const char *sql, /* SQL to be evaluated */ 388 int (*callback)(void*,int,char**,char**), /* Callback function */ 389 void *, /* 1st argument to callback */ 390 char **errmsg /* Error msg written here */ 391 ); 392 393 /* 394 ** CAPI3REF: Result Codes 395 ** KEYWORDS: {result code definitions} 396 ** 397 ** Many SQLite functions return an integer result code from the set shown 398 ** here in order to indicate success or failure. 399 ** 400 ** New error codes may be added in future versions of SQLite. 401 ** 402 ** See also: [extended result code definitions] 403 */ 404 #define SQLITE_OK 0 /* Successful result */ 405 /* beginning-of-error-codes */ 406 #define SQLITE_ERROR 1 /* SQL error or missing database */ 407 #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ 408 #define SQLITE_PERM 3 /* Access permission denied */ 409 #define SQLITE_ABORT 4 /* Callback routine requested an abort */ 410 #define SQLITE_BUSY 5 /* The database file is locked */ 411 #define SQLITE_LOCKED 6 /* A table in the database is locked */ 412 #define SQLITE_NOMEM 7 /* A malloc() failed */ 413 #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 414 #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ 415 #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 416 #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 417 #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ 418 #define SQLITE_FULL 13 /* Insertion failed because database is full */ 419 #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 420 #define SQLITE_PROTOCOL 15 /* Database lock protocol error */ 421 #define SQLITE_EMPTY 16 /* Database is empty */ 422 #define SQLITE_SCHEMA 17 /* The database schema changed */ 423 #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ 424 #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ 425 #define SQLITE_MISMATCH 20 /* Data type mismatch */ 426 #define SQLITE_MISUSE 21 /* Library used incorrectly */ 427 #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 428 #define SQLITE_AUTH 23 /* Authorization denied */ 429 #define SQLITE_FORMAT 24 /* Auxiliary database format error */ 430 #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ 431 #define SQLITE_NOTADB 26 /* File opened that is not a database file */ 432 #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ 433 #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ 434 #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ 435 #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ 436 /* end-of-error-codes */ 437 438 /* 439 ** CAPI3REF: Extended Result Codes 440 ** KEYWORDS: {extended result code definitions} 441 ** 442 ** In its default configuration, SQLite API routines return one of 30 integer 443 ** [result codes]. However, experience has shown that many of 444 ** these result codes are too coarse-grained. They do not provide as 445 ** much information about problems as programmers might like. In an effort to 446 ** address this, newer versions of SQLite (version 3.3.8 and later) include 447 ** support for additional result codes that provide more detailed information 448 ** about errors. These [extended result codes] are enabled or disabled 449 ** on a per database connection basis using the 450 ** [sqlite3_extended_result_codes()] API. Or, the extended code for 451 ** the most recent error can be obtained using 452 ** [sqlite3_extended_errcode()]. 453 */ 454 #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) 455 #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) 456 #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) 457 #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) 458 #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) 459 #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) 460 #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) 461 #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) 462 #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) 463 #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) 464 #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) 465 #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) 466 #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) 467 #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) 468 #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) 469 #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) 470 #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) 471 #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) 472 #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) 473 #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) 474 #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) 475 #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) 476 #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) 477 #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) 478 #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) 479 #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) 480 #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) 481 #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) 482 #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) 483 #define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) 484 #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) 485 #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) 486 #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) 487 #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) 488 #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) 489 #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) 490 #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) 491 #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) 492 #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) 493 #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) 494 #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) 495 #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) 496 #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) 497 #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) 498 #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) 499 #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) 500 #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) 501 #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) 502 #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) 503 #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) 504 #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) 505 #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) 506 #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) 507 #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) 508 509 /* 510 ** CAPI3REF: Flags For File Open Operations 511 ** 512 ** These bit values are intended for use in the 513 ** 3rd parameter to the [sqlite3_open_v2()] interface and 514 ** in the 4th parameter to the [sqlite3_vfs.xOpen] method. 515 */ 516 #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ 517 #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ 518 #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ 519 #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ 520 #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ 521 #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ 522 #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ 523 #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ 524 #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ 525 #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ 526 #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ 527 #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ 528 #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ 529 #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ 530 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ 531 #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ 532 #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ 533 #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ 534 #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ 535 #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ 536 537 /* Reserved: 0x00F00000 */ 538 539 /* 540 ** CAPI3REF: Device Characteristics 541 ** 542 ** The xDeviceCharacteristics method of the [sqlite3_io_methods] 543 ** object returns an integer which is a vector of these 544 ** bit values expressing I/O characteristics of the mass storage 545 ** device that holds the file that the [sqlite3_io_methods] 546 ** refers to. 547 ** 548 ** The SQLITE_IOCAP_ATOMIC property means that all writes of 549 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 550 ** mean that writes of blocks that are nnn bytes in size and 551 ** are aligned to an address which is an integer multiple of 552 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 553 ** that when data is appended to a file, the data is appended 554 ** first then the size of the file is extended, never the other 555 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 556 ** information is written to disk in the same order as calls 557 ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that 558 ** after reboot following a crash or power loss, the only bytes in a 559 ** file that were written at the application level might have changed 560 ** and that adjacent bytes, even bytes within the same sector are 561 ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 562 ** flag indicate that a file cannot be deleted when open. The 563 ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on 564 ** read-only media and cannot be changed even by processes with 565 ** elevated privileges. 566 */ 567 #define SQLITE_IOCAP_ATOMIC 0x00000001 568 #define SQLITE_IOCAP_ATOMIC512 0x00000002 569 #define SQLITE_IOCAP_ATOMIC1K 0x00000004 570 #define SQLITE_IOCAP_ATOMIC2K 0x00000008 571 #define SQLITE_IOCAP_ATOMIC4K 0x00000010 572 #define SQLITE_IOCAP_ATOMIC8K 0x00000020 573 #define SQLITE_IOCAP_ATOMIC16K 0x00000040 574 #define SQLITE_IOCAP_ATOMIC32K 0x00000080 575 #define SQLITE_IOCAP_ATOMIC64K 0x00000100 576 #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 577 #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 578 #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 579 #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 580 #define SQLITE_IOCAP_IMMUTABLE 0x00002000 581 582 /* 583 ** CAPI3REF: File Locking Levels 584 ** 585 ** SQLite uses one of these integer values as the second 586 ** argument to calls it makes to the xLock() and xUnlock() methods 587 ** of an [sqlite3_io_methods] object. 588 */ 589 #define SQLITE_LOCK_NONE 0 590 #define SQLITE_LOCK_SHARED 1 591 #define SQLITE_LOCK_RESERVED 2 592 #define SQLITE_LOCK_PENDING 3 593 #define SQLITE_LOCK_EXCLUSIVE 4 594 595 /* 596 ** CAPI3REF: Synchronization Type Flags 597 ** 598 ** When SQLite invokes the xSync() method of an 599 ** [sqlite3_io_methods] object it uses a combination of 600 ** these integer values as the second argument. 601 ** 602 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the 603 ** sync operation only needs to flush data to mass storage. Inode 604 ** information need not be flushed. If the lower four bits of the flag 605 ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. 606 ** If the lower four bits equal SQLITE_SYNC_FULL, that means 607 ** to use Mac OS X style fullsync instead of fsync(). 608 ** 609 ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags 610 ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL 611 ** settings. The [synchronous pragma] determines when calls to the 612 ** xSync VFS method occur and applies uniformly across all platforms. 613 ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how 614 ** energetic or rigorous or forceful the sync operations are and 615 ** only make a difference on Mac OSX for the default SQLite code. 616 ** (Third-party VFS implementations might also make the distinction 617 ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the 618 ** operating systems natively supported by SQLite, only Mac OSX 619 ** cares about the difference.) 620 */ 621 #define SQLITE_SYNC_NORMAL 0x00002 622 #define SQLITE_SYNC_FULL 0x00003 623 #define SQLITE_SYNC_DATAONLY 0x00010 624 625 /* 626 ** CAPI3REF: OS Interface Open File Handle 627 ** 628 ** An [sqlite3_file] object represents an open file in the 629 ** [sqlite3_vfs | OS interface layer]. Individual OS interface 630 ** implementations will 631 ** want to subclass this object by appending additional fields 632 ** for their own use. The pMethods entry is a pointer to an 633 ** [sqlite3_io_methods] object that defines methods for performing 634 ** I/O operations on the open file. 635 */ 636 typedef struct sqlite3_file sqlite3_file; 637 struct sqlite3_file { 638 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ 639 }; 640 641 /* 642 ** CAPI3REF: OS Interface File Virtual Methods Object 643 ** 644 ** Every file opened by the [sqlite3_vfs.xOpen] method populates an 645 ** [sqlite3_file] object (or, more commonly, a subclass of the 646 ** [sqlite3_file] object) with a pointer to an instance of this object. 647 ** This object defines the methods used to perform various operations 648 ** against the open file represented by the [sqlite3_file] object. 649 ** 650 ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 651 ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method 652 ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The 653 ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] 654 ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element 655 ** to NULL. 656 ** 657 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or 658 ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). 659 ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] 660 ** flag may be ORed in to indicate that only the data of the file 661 ** and not its inode needs to be synced. 662 ** 663 ** The integer values to xLock() and xUnlock() are one of 664 ** <ul> 665 ** <li> [SQLITE_LOCK_NONE], 666 ** <li> [SQLITE_LOCK_SHARED], 667 ** <li> [SQLITE_LOCK_RESERVED], 668 ** <li> [SQLITE_LOCK_PENDING], or 669 ** <li> [SQLITE_LOCK_EXCLUSIVE]. 670 ** </ul> 671 ** xLock() increases the lock. xUnlock() decreases the lock. 672 ** The xCheckReservedLock() method checks whether any database connection, 673 ** either in this process or in some other process, is holding a RESERVED, 674 ** PENDING, or EXCLUSIVE lock on the file. It returns true 675 ** if such a lock exists and false otherwise. 676 ** 677 ** The xFileControl() method is a generic interface that allows custom 678 ** VFS implementations to directly control an open file using the 679 ** [sqlite3_file_control()] interface. The second "op" argument is an 680 ** integer opcode. The third argument is a generic pointer intended to 681 ** point to a structure that may contain arguments or space in which to 682 ** write return values. Potential uses for xFileControl() might be 683 ** functions to enable blocking locks with timeouts, to change the 684 ** locking strategy (for example to use dot-file locks), to inquire 685 ** about the status of a lock, or to break stale locks. The SQLite 686 ** core reserves all opcodes less than 100 for its own use. 687 ** A [file control opcodes | list of opcodes] less than 100 is available. 688 ** Applications that define a custom xFileControl method should use opcodes 689 ** greater than 100 to avoid conflicts. VFS implementations should 690 ** return [SQLITE_NOTFOUND] for file control opcodes that they do not 691 ** recognize. 692 ** 693 ** The xSectorSize() method returns the sector size of the 694 ** device that underlies the file. The sector size is the 695 ** minimum write that can be performed without disturbing 696 ** other bytes in the file. The xDeviceCharacteristics() 697 ** method returns a bit vector describing behaviors of the 698 ** underlying device: 699 ** 700 ** <ul> 701 ** <li> [SQLITE_IOCAP_ATOMIC] 702 ** <li> [SQLITE_IOCAP_ATOMIC512] 703 ** <li> [SQLITE_IOCAP_ATOMIC1K] 704 ** <li> [SQLITE_IOCAP_ATOMIC2K] 705 ** <li> [SQLITE_IOCAP_ATOMIC4K] 706 ** <li> [SQLITE_IOCAP_ATOMIC8K] 707 ** <li> [SQLITE_IOCAP_ATOMIC16K] 708 ** <li> [SQLITE_IOCAP_ATOMIC32K] 709 ** <li> [SQLITE_IOCAP_ATOMIC64K] 710 ** <li> [SQLITE_IOCAP_SAFE_APPEND] 711 ** <li> [SQLITE_IOCAP_SEQUENTIAL] 712 ** </ul> 713 ** 714 ** The SQLITE_IOCAP_ATOMIC property means that all writes of 715 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 716 ** mean that writes of blocks that are nnn bytes in size and 717 ** are aligned to an address which is an integer multiple of 718 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 719 ** that when data is appended to a file, the data is appended 720 ** first then the size of the file is extended, never the other 721 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 722 ** information is written to disk in the same order as calls 723 ** to xWrite(). 724 ** 725 ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill 726 ** in the unread portions of the buffer with zeros. A VFS that 727 ** fails to zero-fill short reads might seem to work. However, 728 ** failure to zero-fill short reads will eventually lead to 729 ** database corruption. 730 */ 731 typedef struct sqlite3_io_methods sqlite3_io_methods; 732 struct sqlite3_io_methods { 733 int iVersion; 734 int (*xClose)(sqlite3_file*); 735 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); 736 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); 737 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); 738 int (*xSync)(sqlite3_file*, int flags); 739 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); 740 int (*xLock)(sqlite3_file*, int); 741 int (*xUnlock)(sqlite3_file*, int); 742 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); 743 int (*xFileControl)(sqlite3_file*, int op, void *pArg); 744 int (*xSectorSize)(sqlite3_file*); 745 int (*xDeviceCharacteristics)(sqlite3_file*); 746 /* Methods above are valid for version 1 */ 747 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); 748 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); 749 void (*xShmBarrier)(sqlite3_file*); 750 int (*xShmUnmap)(sqlite3_file*, int deleteFlag); 751 /* Methods above are valid for version 2 */ 752 int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); 753 int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); 754 /* Methods above are valid for version 3 */ 755 /* Additional methods may be added in future releases */ 756 }; 757 758 /* 759 ** CAPI3REF: Standard File Control Opcodes 760 ** KEYWORDS: {file control opcodes} {file control opcode} 761 ** 762 ** These integer constants are opcodes for the xFileControl method 763 ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] 764 ** interface. 765 ** 766 ** <ul> 767 ** <li>[[SQLITE_FCNTL_LOCKSTATE]] 768 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This 769 ** opcode causes the xFileControl method to write the current state of 770 ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], 771 ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) 772 ** into an integer that the pArg argument points to. This capability 773 ** is used during testing and is only available when the SQLITE_TEST 774 ** compile-time option is used. 775 ** 776 ** <li>[[SQLITE_FCNTL_SIZE_HINT]] 777 ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS 778 ** layer a hint of how large the database file will grow to be during the 779 ** current transaction. This hint is not guaranteed to be accurate but it 780 ** is often close. The underlying VFS might choose to preallocate database 781 ** file space based on this hint in order to help writes to the database 782 ** file run faster. 783 ** 784 ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] 785 ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS 786 ** extends and truncates the database file in chunks of a size specified 787 ** by the user. The fourth argument to [sqlite3_file_control()] should 788 ** point to an integer (type int) containing the new chunk-size to use 789 ** for the nominated database. Allocating database file space in large 790 ** chunks (say 1MB at a time), may reduce file-system fragmentation and 791 ** improve performance on some systems. 792 ** 793 ** <li>[[SQLITE_FCNTL_FILE_POINTER]] 794 ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer 795 ** to the [sqlite3_file] object associated with a particular database 796 ** connection. See the [sqlite3_file_control()] documentation for 797 ** additional information. 798 ** 799 ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] 800 ** No longer in use. 801 ** 802 ** <li>[[SQLITE_FCNTL_SYNC]] 803 ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and 804 ** sent to the VFS immediately before the xSync method is invoked on a 805 ** database file descriptor. Or, if the xSync method is not invoked 806 ** because the user has configured SQLite with 807 ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 808 ** of the xSync method. In most cases, the pointer argument passed with 809 ** this file-control is NULL. However, if the database file is being synced 810 ** as part of a multi-database commit, the argument points to a nul-terminated 811 ** string containing the transactions master-journal file name. VFSes that 812 ** do not need this signal should silently ignore this opcode. Applications 813 ** should not call [sqlite3_file_control()] with this opcode as doing so may 814 ** disrupt the operation of the specialized VFSes that do require it. 815 ** 816 ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] 817 ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite 818 ** and sent to the VFS after a transaction has been committed immediately 819 ** but before the database is unlocked. VFSes that do not need this signal 820 ** should silently ignore this opcode. Applications should not call 821 ** [sqlite3_file_control()] with this opcode as doing so may disrupt the 822 ** operation of the specialized VFSes that do require it. 823 ** 824 ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] 825 ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic 826 ** retry counts and intervals for certain disk I/O operations for the 827 ** windows [VFS] in order to provide robustness in the presence of 828 ** anti-virus programs. By default, the windows VFS will retry file read, 829 ** file write, and file delete operations up to 10 times, with a delay 830 ** of 25 milliseconds before the first retry and with the delay increasing 831 ** by an additional 25 milliseconds with each subsequent retry. This 832 ** opcode allows these two values (10 retries and 25 milliseconds of delay) 833 ** to be adjusted. The values are changed for all database connections 834 ** within the same process. The argument is a pointer to an array of two 835 ** integers where the first integer i the new retry count and the second 836 ** integer is the delay. If either integer is negative, then the setting 837 ** is not changed but instead the prior value of that setting is written 838 ** into the array entry, allowing the current retry settings to be 839 ** interrogated. The zDbName parameter is ignored. 840 ** 841 ** <li>[[SQLITE_FCNTL_PERSIST_WAL]] 842 ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the 843 ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary 844 ** write ahead log and shared memory files used for transaction control 845 ** are automatically deleted when the latest connection to the database 846 ** closes. Setting persistent WAL mode causes those files to persist after 847 ** close. Persisting the files is useful when other processes that do not 848 ** have write permission on the directory containing the database file want 849 ** to read the database file, as the WAL and shared memory files must exist 850 ** in order for the database to be readable. The fourth parameter to 851 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 852 ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent 853 ** WAL mode. If the integer is -1, then it is overwritten with the current 854 ** WAL persistence setting. 855 ** 856 ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] 857 ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the 858 ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting 859 ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the 860 ** xDeviceCharacteristics methods. The fourth parameter to 861 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 862 ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage 863 ** mode. If the integer is -1, then it is overwritten with the current 864 ** zero-damage mode setting. 865 ** 866 ** <li>[[SQLITE_FCNTL_OVERWRITE]] 867 ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening 868 ** a write transaction to indicate that, unless it is rolled back for some 869 ** reason, the entire database file will be overwritten by the current 870 ** transaction. This is used by VACUUM operations. 871 ** 872 ** <li>[[SQLITE_FCNTL_VFSNAME]] 873 ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of 874 ** all [VFSes] in the VFS stack. The names are of all VFS shims and the 875 ** final bottom-level VFS are written into memory obtained from 876 ** [sqlite3_malloc()] and the result is stored in the char* variable 877 ** that the fourth parameter of [sqlite3_file_control()] points to. 878 ** The caller is responsible for freeing the memory when done. As with 879 ** all file-control actions, there is no guarantee that this will actually 880 ** do anything. Callers should initialize the char* variable to a NULL 881 ** pointer in case this file-control is not implemented. This file-control 882 ** is intended for diagnostic use only. 883 ** 884 ** <li>[[SQLITE_FCNTL_PRAGMA]] 885 ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 886 ** file control is sent to the open [sqlite3_file] object corresponding 887 ** to the database file to which the pragma statement refers. ^The argument 888 ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of 889 ** pointers to strings (char**) in which the second element of the array 890 ** is the name of the pragma and the third element is the argument to the 891 ** pragma or NULL if the pragma has no argument. ^The handler for an 892 ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element 893 ** of the char** argument point to a string obtained from [sqlite3_mprintf()] 894 ** or the equivalent and that string will become the result of the pragma or 895 ** the error message if the pragma fails. ^If the 896 ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 897 ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] 898 ** file control returns [SQLITE_OK], then the parser assumes that the 899 ** VFS has handled the PRAGMA itself and the parser generates a no-op 900 ** prepared statement if result string is NULL, or that returns a copy 901 ** of the result string if the string is non-NULL. 902 ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns 903 ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means 904 ** that the VFS encountered an error while handling the [PRAGMA] and the 905 ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] 906 ** file control occurs at the beginning of pragma statement analysis and so 907 ** it is able to override built-in [PRAGMA] statements. 908 ** 909 ** <li>[[SQLITE_FCNTL_BUSYHANDLER]] 910 ** ^The [SQLITE_FCNTL_BUSYHANDLER] 911 ** file-control may be invoked by SQLite on the database file handle 912 ** shortly after it is opened in order to provide a custom VFS with access 913 ** to the connections busy-handler callback. The argument is of type (void **) 914 ** - an array of two (void *) values. The first (void *) actually points 915 ** to a function of type (int (*)(void *)). In order to invoke the connections 916 ** busy-handler, this function should be invoked with the second (void *) in 917 ** the array as the only argument. If it returns non-zero, then the operation 918 ** should be retried. If it returns zero, the custom VFS should abandon the 919 ** current operation. 920 ** 921 ** <li>[[SQLITE_FCNTL_TEMPFILENAME]] 922 ** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control 923 ** to have SQLite generate a 924 ** temporary filename using the same algorithm that is followed to generate 925 ** temporary filenames for TEMP tables and other internal uses. The 926 ** argument should be a char** which will be filled with the filename 927 ** written into memory obtained from [sqlite3_malloc()]. The caller should 928 ** invoke [sqlite3_free()] on the result to avoid a memory leak. 929 ** 930 ** <li>[[SQLITE_FCNTL_MMAP_SIZE]] 931 ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the 932 ** maximum number of bytes that will be used for memory-mapped I/O. 933 ** The argument is a pointer to a value of type sqlite3_int64 that 934 ** is an advisory maximum number of bytes in the file to memory map. The 935 ** pointer is overwritten with the old value. The limit is not changed if 936 ** the value originally pointed to is negative, and so the current limit 937 ** can be queried by passing in a pointer to a negative number. This 938 ** file-control is used internally to implement [PRAGMA mmap_size]. 939 ** 940 ** <li>[[SQLITE_FCNTL_TRACE]] 941 ** The [SQLITE_FCNTL_TRACE] file control provides advisory information 942 ** to the VFS about what the higher layers of the SQLite stack are doing. 943 ** This file control is used by some VFS activity tracing [shims]. 944 ** The argument is a zero-terminated string. Higher layers in the 945 ** SQLite stack may generate instances of this file control if 946 ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. 947 ** 948 ** <li>[[SQLITE_FCNTL_HAS_MOVED]] 949 ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a 950 ** pointer to an integer and it writes a boolean into that integer depending 951 ** on whether or not the file has been renamed, moved, or deleted since it 952 ** was first opened. 953 ** 954 ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] 955 ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This 956 ** opcode causes the xFileControl method to swap the file handle with the one 957 ** pointed to by the pArg argument. This capability is used during testing 958 ** and only needs to be supported when SQLITE_TEST is defined. 959 ** 960 ** <li>[[SQLITE_FCNTL_WAL_BLOCK]] 961 ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might 962 ** be advantageous to block on the next WAL lock if the lock is not immediately 963 ** available. The WAL subsystem issues this signal during rare 964 ** circumstances in order to fix a problem with priority inversion. 965 ** Applications should <em>not</em> use this file-control. 966 ** 967 ** <li>[[SQLITE_FCNTL_ZIPVFS]] 968 ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other 969 ** VFS should return SQLITE_NOTFOUND for this opcode. 970 ** 971 ** <li>[[SQLITE_FCNTL_RBU]] 972 ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by 973 ** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for 974 ** this opcode. 975 ** </ul> 976 */ 977 #define SQLITE_FCNTL_LOCKSTATE 1 978 #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 979 #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 980 #define SQLITE_FCNTL_LAST_ERRNO 4 981 #define SQLITE_FCNTL_SIZE_HINT 5 982 #define SQLITE_FCNTL_CHUNK_SIZE 6 983 #define SQLITE_FCNTL_FILE_POINTER 7 984 #define SQLITE_FCNTL_SYNC_OMITTED 8 985 #define SQLITE_FCNTL_WIN32_AV_RETRY 9 986 #define SQLITE_FCNTL_PERSIST_WAL 10 987 #define SQLITE_FCNTL_OVERWRITE 11 988 #define SQLITE_FCNTL_VFSNAME 12 989 #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 990 #define SQLITE_FCNTL_PRAGMA 14 991 #define SQLITE_FCNTL_BUSYHANDLER 15 992 #define SQLITE_FCNTL_TEMPFILENAME 16 993 #define SQLITE_FCNTL_MMAP_SIZE 18 994 #define SQLITE_FCNTL_TRACE 19 995 #define SQLITE_FCNTL_HAS_MOVED 20 996 #define SQLITE_FCNTL_SYNC 21 997 #define SQLITE_FCNTL_COMMIT_PHASETWO 22 998 #define SQLITE_FCNTL_WIN32_SET_HANDLE 23 999 #define SQLITE_FCNTL_WAL_BLOCK 24 1000 #define SQLITE_FCNTL_ZIPVFS 25 1001 #define SQLITE_FCNTL_RBU 26 1002 1003 /* deprecated names */ 1004 #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE 1005 #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE 1006 #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO 1007 1008 1009 /* 1010 ** CAPI3REF: Mutex Handle 1011 ** 1012 ** The mutex module within SQLite defines [sqlite3_mutex] to be an 1013 ** abstract type for a mutex object. The SQLite core never looks 1014 ** at the internal representation of an [sqlite3_mutex]. It only 1015 ** deals with pointers to the [sqlite3_mutex] object. 1016 ** 1017 ** Mutexes are created using [sqlite3_mutex_alloc()]. 1018 */ 1019 typedef struct sqlite3_mutex sqlite3_mutex; 1020 1021 /* 1022 ** CAPI3REF: OS Interface Object 1023 ** 1024 ** An instance of the sqlite3_vfs object defines the interface between 1025 ** the SQLite core and the underlying operating system. The "vfs" 1026 ** in the name of the object stands for "virtual file system". See 1027 ** the [VFS | VFS documentation] for further information. 1028 ** 1029 ** The value of the iVersion field is initially 1 but may be larger in 1030 ** future versions of SQLite. Additional fields may be appended to this 1031 ** object when the iVersion value is increased. Note that the structure 1032 ** of the sqlite3_vfs object changes in the transaction between 1033 ** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not 1034 ** modified. 1035 ** 1036 ** The szOsFile field is the size of the subclassed [sqlite3_file] 1037 ** structure used by this VFS. mxPathname is the maximum length of 1038 ** a pathname in this VFS. 1039 ** 1040 ** Registered sqlite3_vfs objects are kept on a linked list formed by 1041 ** the pNext pointer. The [sqlite3_vfs_register()] 1042 ** and [sqlite3_vfs_unregister()] interfaces manage this list 1043 ** in a thread-safe way. The [sqlite3_vfs_find()] interface 1044 ** searches the list. Neither the application code nor the VFS 1045 ** implementation should use the pNext pointer. 1046 ** 1047 ** The pNext field is the only field in the sqlite3_vfs 1048 ** structure that SQLite will ever modify. SQLite will only access 1049 ** or modify this field while holding a particular static mutex. 1050 ** The application should never modify anything within the sqlite3_vfs 1051 ** object once the object has been registered. 1052 ** 1053 ** The zName field holds the name of the VFS module. The name must 1054 ** be unique across all VFS modules. 1055 ** 1056 ** [[sqlite3_vfs.xOpen]] 1057 ** ^SQLite guarantees that the zFilename parameter to xOpen 1058 ** is either a NULL pointer or string obtained 1059 ** from xFullPathname() with an optional suffix added. 1060 ** ^If a suffix is added to the zFilename parameter, it will 1061 ** consist of a single "-" character followed by no more than 1062 ** 11 alphanumeric and/or "-" characters. 1063 ** ^SQLite further guarantees that 1064 ** the string will be valid and unchanged until xClose() is 1065 ** called. Because of the previous sentence, 1066 ** the [sqlite3_file] can safely store a pointer to the 1067 ** filename if it needs to remember the filename for some reason. 1068 ** If the zFilename parameter to xOpen is a NULL pointer then xOpen 1069 ** must invent its own temporary name for the file. ^Whenever the 1070 ** xFilename parameter is NULL it will also be the case that the 1071 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. 1072 ** 1073 ** The flags argument to xOpen() includes all bits set in 1074 ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] 1075 ** or [sqlite3_open16()] is used, then flags includes at least 1076 ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 1077 ** If xOpen() opens a file read-only then it sets *pOutFlags to 1078 ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. 1079 ** 1080 ** ^(SQLite will also add one of the following flags to the xOpen() 1081 ** call, depending on the object being opened: 1082 ** 1083 ** <ul> 1084 ** <li> [SQLITE_OPEN_MAIN_DB] 1085 ** <li> [SQLITE_OPEN_MAIN_JOURNAL] 1086 ** <li> [SQLITE_OPEN_TEMP_DB] 1087 ** <li> [SQLITE_OPEN_TEMP_JOURNAL] 1088 ** <li> [SQLITE_OPEN_TRANSIENT_DB] 1089 ** <li> [SQLITE_OPEN_SUBJOURNAL] 1090 ** <li> [SQLITE_OPEN_MASTER_JOURNAL] 1091 ** <li> [SQLITE_OPEN_WAL] 1092 ** </ul>)^ 1093 ** 1094 ** The file I/O implementation can use the object type flags to 1095 ** change the way it deals with files. For example, an application 1096 ** that does not care about crash recovery or rollback might make 1097 ** the open of a journal file a no-op. Writes to this journal would 1098 ** also be no-ops, and any attempt to read the journal would return 1099 ** SQLITE_IOERR. Or the implementation might recognize that a database 1100 ** file will be doing page-aligned sector reads and writes in a random 1101 ** order and set up its I/O subsystem accordingly. 1102 ** 1103 ** SQLite might also add one of the following flags to the xOpen method: 1104 ** 1105 ** <ul> 1106 ** <li> [SQLITE_OPEN_DELETEONCLOSE] 1107 ** <li> [SQLITE_OPEN_EXCLUSIVE] 1108 ** </ul> 1109 ** 1110 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be 1111 ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] 1112 ** will be set for TEMP databases and their journals, transient 1113 ** databases, and subjournals. 1114 ** 1115 ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction 1116 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly 1117 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() 1118 ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 1119 ** SQLITE_OPEN_CREATE, is used to indicate that file should always 1120 ** be created, and that it is an error if it already exists. 1121 ** It is <i>not</i> used to indicate the file should be opened 1122 ** for exclusive access. 1123 ** 1124 ** ^At least szOsFile bytes of memory are allocated by SQLite 1125 ** to hold the [sqlite3_file] structure passed as the third 1126 ** argument to xOpen. The xOpen method does not have to 1127 ** allocate the structure; it should just fill it in. Note that 1128 ** the xOpen method must set the sqlite3_file.pMethods to either 1129 ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do 1130 ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods 1131 ** element will be valid after xOpen returns regardless of the success 1132 ** or failure of the xOpen call. 1133 ** 1134 ** [[sqlite3_vfs.xAccess]] 1135 ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 1136 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to 1137 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] 1138 ** to test whether a file is at least readable. The file can be a 1139 ** directory. 1140 ** 1141 ** ^SQLite will always allocate at least mxPathname+1 bytes for the 1142 ** output buffer xFullPathname. The exact size of the output buffer 1143 ** is also passed as a parameter to both methods. If the output buffer 1144 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is 1145 ** handled as a fatal error by SQLite, vfs implementations should endeavor 1146 ** to prevent this by setting mxPathname to a sufficiently large value. 1147 ** 1148 ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() 1149 ** interfaces are not strictly a part of the filesystem, but they are 1150 ** included in the VFS structure for completeness. 1151 ** The xRandomness() function attempts to return nBytes bytes 1152 ** of good-quality randomness into zOut. The return value is 1153 ** the actual number of bytes of randomness obtained. 1154 ** The xSleep() method causes the calling thread to sleep for at 1155 ** least the number of microseconds given. ^The xCurrentTime() 1156 ** method returns a Julian Day Number for the current date and time as 1157 ** a floating point value. 1158 ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian 1159 ** Day Number multiplied by 86400000 (the number of milliseconds in 1160 ** a 24-hour day). 1161 ** ^SQLite will use the xCurrentTimeInt64() method to get the current 1162 ** date and time if that method is available (if iVersion is 2 or 1163 ** greater and the function pointer is not NULL) and will fall back 1164 ** to xCurrentTime() if xCurrentTimeInt64() is unavailable. 1165 ** 1166 ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces 1167 ** are not used by the SQLite core. These optional interfaces are provided 1168 ** by some VFSes to facilitate testing of the VFS code. By overriding 1169 ** system calls with functions under its control, a test program can 1170 ** simulate faults and error conditions that would otherwise be difficult 1171 ** or impossible to induce. The set of system calls that can be overridden 1172 ** varies from one VFS to another, and from one version of the same VFS to the 1173 ** next. Applications that use these interfaces must be prepared for any 1174 ** or all of these interfaces to be NULL or for their behavior to change 1175 ** from one release to the next. Applications must not attempt to access 1176 ** any of these methods if the iVersion of the VFS is less than 3. 1177 */ 1178 typedef struct sqlite3_vfs sqlite3_vfs; 1179 typedef void (*sqlite3_syscall_ptr)(void); 1180 struct sqlite3_vfs { 1181 int iVersion; /* Structure version number (currently 3) */ 1182 int szOsFile; /* Size of subclassed sqlite3_file */ 1183 int mxPathname; /* Maximum file pathname length */ 1184 sqlite3_vfs *pNext; /* Next registered VFS */ 1185 const char *zName; /* Name of this virtual file system */ 1186 void *pAppData; /* Pointer to application-specific data */ 1187 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, 1188 int flags, int *pOutFlags); 1189 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); 1190 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); 1191 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); 1192 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); 1193 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); 1194 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); 1195 void (*xDlClose)(sqlite3_vfs*, void*); 1196 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); 1197 int (*xSleep)(sqlite3_vfs*, int microseconds); 1198 int (*xCurrentTime)(sqlite3_vfs*, double*); 1199 int (*xGetLastError)(sqlite3_vfs*, int, char *); 1200 /* 1201 ** The methods above are in version 1 of the sqlite_vfs object 1202 ** definition. Those that follow are added in version 2 or later 1203 */ 1204 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); 1205 /* 1206 ** The methods above are in versions 1 and 2 of the sqlite_vfs object. 1207 ** Those below are for version 3 and greater. 1208 */ 1209 int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); 1210 sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); 1211 const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); 1212 /* 1213 ** The methods above are in versions 1 through 3 of the sqlite_vfs object. 1214 ** New fields may be appended in figure versions. The iVersion 1215 ** value will increment whenever this happens. 1216 */ 1217 }; 1218 1219 /* 1220 ** CAPI3REF: Flags for the xAccess VFS method 1221 ** 1222 ** These integer constants can be used as the third parameter to 1223 ** the xAccess method of an [sqlite3_vfs] object. They determine 1224 ** what kind of permissions the xAccess method is looking for. 1225 ** With SQLITE_ACCESS_EXISTS, the xAccess method 1226 ** simply checks whether the file exists. 1227 ** With SQLITE_ACCESS_READWRITE, the xAccess method 1228 ** checks whether the named directory is both readable and writable 1229 ** (in other words, if files can be added, removed, and renamed within 1230 ** the directory). 1231 ** The SQLITE_ACCESS_READWRITE constant is currently used only by the 1232 ** [temp_store_directory pragma], though this could change in a future 1233 ** release of SQLite. 1234 ** With SQLITE_ACCESS_READ, the xAccess method 1235 ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is 1236 ** currently unused, though it might be used in a future release of 1237 ** SQLite. 1238 */ 1239 #define SQLITE_ACCESS_EXISTS 0 1240 #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ 1241 #define SQLITE_ACCESS_READ 2 /* Unused */ 1242 1243 /* 1244 ** CAPI3REF: Flags for the xShmLock VFS method 1245 ** 1246 ** These integer constants define the various locking operations 1247 ** allowed by the xShmLock method of [sqlite3_io_methods]. The 1248 ** following are the only legal combinations of flags to the 1249 ** xShmLock method: 1250 ** 1251 ** <ul> 1252 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED 1253 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE 1254 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED 1255 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE 1256 ** </ul> 1257 ** 1258 ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as 1259 ** was given on the corresponding lock. 1260 ** 1261 ** The xShmLock method can transition between unlocked and SHARED or 1262 ** between unlocked and EXCLUSIVE. It cannot transition between SHARED 1263 ** and EXCLUSIVE. 1264 */ 1265 #define SQLITE_SHM_UNLOCK 1 1266 #define SQLITE_SHM_LOCK 2 1267 #define SQLITE_SHM_SHARED 4 1268 #define SQLITE_SHM_EXCLUSIVE 8 1269 1270 /* 1271 ** CAPI3REF: Maximum xShmLock index 1272 ** 1273 ** The xShmLock method on [sqlite3_io_methods] may use values 1274 ** between 0 and this upper bound as its "offset" argument. 1275 ** The SQLite core will never attempt to acquire or release a 1276 ** lock outside of this range 1277 */ 1278 #define SQLITE_SHM_NLOCK 8 1279 1280 1281 /* 1282 ** CAPI3REF: Initialize The SQLite Library 1283 ** 1284 ** ^The sqlite3_initialize() routine initializes the 1285 ** SQLite library. ^The sqlite3_shutdown() routine 1286 ** deallocates any resources that were allocated by sqlite3_initialize(). 1287 ** These routines are designed to aid in process initialization and 1288 ** shutdown on embedded systems. Workstation applications using 1289 ** SQLite normally do not need to invoke either of these routines. 1290 ** 1291 ** A call to sqlite3_initialize() is an "effective" call if it is 1292 ** the first time sqlite3_initialize() is invoked during the lifetime of 1293 ** the process, or if it is the first time sqlite3_initialize() is invoked 1294 ** following a call to sqlite3_shutdown(). ^(Only an effective call 1295 ** of sqlite3_initialize() does any initialization. All other calls 1296 ** are harmless no-ops.)^ 1297 ** 1298 ** A call to sqlite3_shutdown() is an "effective" call if it is the first 1299 ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only 1300 ** an effective call to sqlite3_shutdown() does any deinitialization. 1301 ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ 1302 ** 1303 ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() 1304 ** is not. The sqlite3_shutdown() interface must only be called from a 1305 ** single thread. All open [database connections] must be closed and all 1306 ** other SQLite resources must be deallocated prior to invoking 1307 ** sqlite3_shutdown(). 1308 ** 1309 ** Among other things, ^sqlite3_initialize() will invoke 1310 ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() 1311 ** will invoke sqlite3_os_end(). 1312 ** 1313 ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. 1314 ** ^If for some reason, sqlite3_initialize() is unable to initialize 1315 ** the library (perhaps it is unable to allocate a needed resource such 1316 ** as a mutex) it returns an [error code] other than [SQLITE_OK]. 1317 ** 1318 ** ^The sqlite3_initialize() routine is called internally by many other 1319 ** SQLite interfaces so that an application usually does not need to 1320 ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] 1321 ** calls sqlite3_initialize() so the SQLite library will be automatically 1322 ** initialized when [sqlite3_open()] is called if it has not be initialized 1323 ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] 1324 ** compile-time option, then the automatic calls to sqlite3_initialize() 1325 ** are omitted and the application must call sqlite3_initialize() directly 1326 ** prior to using any other SQLite interface. For maximum portability, 1327 ** it is recommended that applications always invoke sqlite3_initialize() 1328 ** directly prior to using any other SQLite interface. Future releases 1329 ** of SQLite may require this. In other words, the behavior exhibited 1330 ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the 1331 ** default behavior in some future release of SQLite. 1332 ** 1333 ** The sqlite3_os_init() routine does operating-system specific 1334 ** initialization of the SQLite library. The sqlite3_os_end() 1335 ** routine undoes the effect of sqlite3_os_init(). Typical tasks 1336 ** performed by these routines include allocation or deallocation 1337 ** of static resources, initialization of global variables, 1338 ** setting up a default [sqlite3_vfs] module, or setting up 1339 ** a default configuration using [sqlite3_config()]. 1340 ** 1341 ** The application should never invoke either sqlite3_os_init() 1342 ** or sqlite3_os_end() directly. The application should only invoke 1343 ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() 1344 ** interface is called automatically by sqlite3_initialize() and 1345 ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate 1346 ** implementations for sqlite3_os_init() and sqlite3_os_end() 1347 ** are built into SQLite when it is compiled for Unix, Windows, or OS/2. 1348 ** When [custom builds | built for other platforms] 1349 ** (using the [SQLITE_OS_OTHER=1] compile-time 1350 ** option) the application must supply a suitable implementation for 1351 ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied 1352 ** implementation of sqlite3_os_init() or sqlite3_os_end() 1353 ** must return [SQLITE_OK] on success and some other [error code] upon 1354 ** failure. 1355 */ 1356 SQLITE_API int SQLITE_STDCALL sqlite3_initialize(void); 1357 SQLITE_API int SQLITE_STDCALL sqlite3_shutdown(void); 1358 SQLITE_API int SQLITE_STDCALL sqlite3_os_init(void); 1359 SQLITE_API int SQLITE_STDCALL sqlite3_os_end(void); 1360 1361 /* 1362 ** CAPI3REF: Configuring The SQLite Library 1363 ** 1364 ** The sqlite3_config() interface is used to make global configuration 1365 ** changes to SQLite in order to tune SQLite to the specific needs of 1366 ** the application. The default configuration is recommended for most 1367 ** applications and so this routine is usually not necessary. It is 1368 ** provided to support rare applications with unusual needs. 1369 ** 1370 ** <b>The sqlite3_config() interface is not threadsafe. The application 1371 ** must ensure that no other SQLite interfaces are invoked by other 1372 ** threads while sqlite3_config() is running.</b> 1373 ** 1374 ** The sqlite3_config() interface 1375 ** may only be invoked prior to library initialization using 1376 ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. 1377 ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before 1378 ** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. 1379 ** Note, however, that ^sqlite3_config() can be called as part of the 1380 ** implementation of an application-defined [sqlite3_os_init()]. 1381 ** 1382 ** The first argument to sqlite3_config() is an integer 1383 ** [configuration option] that determines 1384 ** what property of SQLite is to be configured. Subsequent arguments 1385 ** vary depending on the [configuration option] 1386 ** in the first argument. 1387 ** 1388 ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. 1389 ** ^If the option is unknown or SQLite is unable to set the option 1390 ** then this routine returns a non-zero [error code]. 1391 */ 1392 SQLITE_API int SQLITE_CDECL sqlite3_config(int, ...); 1393 1394 /* 1395 ** CAPI3REF: Configure database connections 1396 ** METHOD: sqlite3 1397 ** 1398 ** The sqlite3_db_config() interface is used to make configuration 1399 ** changes to a [database connection]. The interface is similar to 1400 ** [sqlite3_config()] except that the changes apply to a single 1401 ** [database connection] (specified in the first argument). 1402 ** 1403 ** The second argument to sqlite3_db_config(D,V,...) is the 1404 ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 1405 ** that indicates what aspect of the [database connection] is being configured. 1406 ** Subsequent arguments vary depending on the configuration verb. 1407 ** 1408 ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if 1409 ** the call is considered successful. 1410 */ 1411 SQLITE_API int SQLITE_CDECL sqlite3_db_config(sqlite3*, int op, ...); 1412 1413 /* 1414 ** CAPI3REF: Memory Allocation Routines 1415 ** 1416 ** An instance of this object defines the interface between SQLite 1417 ** and low-level memory allocation routines. 1418 ** 1419 ** This object is used in only one place in the SQLite interface. 1420 ** A pointer to an instance of this object is the argument to 1421 ** [sqlite3_config()] when the configuration option is 1422 ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. 1423 ** By creating an instance of this object 1424 ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) 1425 ** during configuration, an application can specify an alternative 1426 ** memory allocation subsystem for SQLite to use for all of its 1427 ** dynamic memory needs. 1428 ** 1429 ** Note that SQLite comes with several [built-in memory allocators] 1430 ** that are perfectly adequate for the overwhelming majority of applications 1431 ** and that this object is only useful to a tiny minority of applications 1432 ** with specialized memory allocation requirements. This object is 1433 ** also used during testing of SQLite in order to specify an alternative 1434 ** memory allocator that simulates memory out-of-memory conditions in 1435 ** order to verify that SQLite recovers gracefully from such 1436 ** conditions. 1437 ** 1438 ** The xMalloc, xRealloc, and xFree methods must work like the 1439 ** malloc(), realloc() and free() functions from the standard C library. 1440 ** ^SQLite guarantees that the second argument to 1441 ** xRealloc is always a value returned by a prior call to xRoundup. 1442 ** 1443 ** xSize should return the allocated size of a memory allocation 1444 ** previously obtained from xMalloc or xRealloc. The allocated size 1445 ** is always at least as big as the requested size but may be larger. 1446 ** 1447 ** The xRoundup method returns what would be the allocated size of 1448 ** a memory allocation given a particular requested size. Most memory 1449 ** allocators round up memory allocations at least to the next multiple 1450 ** of 8. Some allocators round up to a larger multiple or to a power of 2. 1451 ** Every memory allocation request coming in through [sqlite3_malloc()] 1452 ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, 1453 ** that causes the corresponding memory allocation to fail. 1454 ** 1455 ** The xInit method initializes the memory allocator. For example, 1456 ** it might allocate any require mutexes or initialize internal data 1457 ** structures. The xShutdown method is invoked (indirectly) by 1458 ** [sqlite3_shutdown()] and should deallocate any resources acquired 1459 ** by xInit. The pAppData pointer is used as the only parameter to 1460 ** xInit and xShutdown. 1461 ** 1462 ** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes 1463 ** the xInit method, so the xInit method need not be threadsafe. The 1464 ** xShutdown method is only called from [sqlite3_shutdown()] so it does 1465 ** not need to be threadsafe either. For all other methods, SQLite 1466 ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the 1467 ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which 1468 ** it is by default) and so the methods are automatically serialized. 1469 ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other 1470 ** methods must be threadsafe or else make their own arrangements for 1471 ** serialization. 1472 ** 1473 ** SQLite will never invoke xInit() more than once without an intervening 1474 ** call to xShutdown(). 1475 */ 1476 typedef struct sqlite3_mem_methods sqlite3_mem_methods; 1477 struct sqlite3_mem_methods { 1478 void *(*xMalloc)(int); /* Memory allocation function */ 1479 void (*xFree)(void*); /* Free a prior allocation */ 1480 void *(*xRealloc)(void*,int); /* Resize an allocation */ 1481 int (*xSize)(void*); /* Return the size of an allocation */ 1482 int (*xRoundup)(int); /* Round up request size to allocation size */ 1483 int (*xInit)(void*); /* Initialize the memory allocator */ 1484 void (*xShutdown)(void*); /* Deinitialize the memory allocator */ 1485 void *pAppData; /* Argument to xInit() and xShutdown() */ 1486 }; 1487 1488 /* 1489 ** CAPI3REF: Configuration Options 1490 ** KEYWORDS: {configuration option} 1491 ** 1492 ** These constants are the available integer configuration options that 1493 ** can be passed as the first argument to the [sqlite3_config()] interface. 1494 ** 1495 ** New configuration options may be added in future releases of SQLite. 1496 ** Existing configuration options might be discontinued. Applications 1497 ** should check the return code from [sqlite3_config()] to make sure that 1498 ** the call worked. The [sqlite3_config()] interface will return a 1499 ** non-zero [error code] if a discontinued or unsupported configuration option 1500 ** is invoked. 1501 ** 1502 ** <dl> 1503 ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> 1504 ** <dd>There are no arguments to this option. ^This option sets the 1505 ** [threading mode] to Single-thread. In other words, it disables 1506 ** all mutexing and puts SQLite into a mode where it can only be used 1507 ** by a single thread. ^If SQLite is compiled with 1508 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1509 ** it is not possible to change the [threading mode] from its default 1510 ** value of Single-thread and so [sqlite3_config()] will return 1511 ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD 1512 ** configuration option.</dd> 1513 ** 1514 ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> 1515 ** <dd>There are no arguments to this option. ^This option sets the 1516 ** [threading mode] to Multi-thread. In other words, it disables 1517 ** mutexing on [database connection] and [prepared statement] objects. 1518 ** The application is responsible for serializing access to 1519 ** [database connections] and [prepared statements]. But other mutexes 1520 ** are enabled so that SQLite will be safe to use in a multi-threaded 1521 ** environment as long as no two threads attempt to use the same 1522 ** [database connection] at the same time. ^If SQLite is compiled with 1523 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1524 ** it is not possible to set the Multi-thread [threading mode] and 1525 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1526 ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> 1527 ** 1528 ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> 1529 ** <dd>There are no arguments to this option. ^This option sets the 1530 ** [threading mode] to Serialized. In other words, this option enables 1531 ** all mutexes including the recursive 1532 ** mutexes on [database connection] and [prepared statement] objects. 1533 ** In this mode (which is the default when SQLite is compiled with 1534 ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access 1535 ** to [database connections] and [prepared statements] so that the 1536 ** application is free to use the same [database connection] or the 1537 ** same [prepared statement] in different threads at the same time. 1538 ** ^If SQLite is compiled with 1539 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1540 ** it is not possible to set the Serialized [threading mode] and 1541 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1542 ** SQLITE_CONFIG_SERIALIZED configuration option.</dd> 1543 ** 1544 ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> 1545 ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 1546 ** a pointer to an instance of the [sqlite3_mem_methods] structure. 1547 ** The argument specifies 1548 ** alternative low-level memory allocation routines to be used in place of 1549 ** the memory allocation routines built into SQLite.)^ ^SQLite makes 1550 ** its own private copy of the content of the [sqlite3_mem_methods] structure 1551 ** before the [sqlite3_config()] call returns.</dd> 1552 ** 1553 ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> 1554 ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which 1555 ** is a pointer to an instance of the [sqlite3_mem_methods] structure. 1556 ** The [sqlite3_mem_methods] 1557 ** structure is filled with the currently defined memory allocation routines.)^ 1558 ** This option can be used to overload the default memory allocation 1559 ** routines with a wrapper that simulations memory allocation failure or 1560 ** tracks memory usage, for example. </dd> 1561 ** 1562 ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> 1563 ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, 1564 ** interpreted as a boolean, which enables or disables the collection of 1565 ** memory allocation statistics. ^(When memory allocation statistics are 1566 ** disabled, the following SQLite interfaces become non-operational: 1567 ** <ul> 1568 ** <li> [sqlite3_memory_used()] 1569 ** <li> [sqlite3_memory_highwater()] 1570 ** <li> [sqlite3_soft_heap_limit64()] 1571 ** <li> [sqlite3_status64()] 1572 ** </ul>)^ 1573 ** ^Memory allocation statistics are enabled by default unless SQLite is 1574 ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory 1575 ** allocation statistics are disabled by default. 1576 ** </dd> 1577 ** 1578 ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> 1579 ** <dd> ^The SQLITE_CONFIG_SCRATCH option specifies a static memory buffer 1580 ** that SQLite can use for scratch memory. ^(There are three arguments 1581 ** to SQLITE_CONFIG_SCRATCH: A pointer an 8-byte 1582 ** aligned memory buffer from which the scratch allocations will be 1583 ** drawn, the size of each scratch allocation (sz), 1584 ** and the maximum number of scratch allocations (N).)^ 1585 ** The first argument must be a pointer to an 8-byte aligned buffer 1586 ** of at least sz*N bytes of memory. 1587 ** ^SQLite will not use more than one scratch buffers per thread. 1588 ** ^SQLite will never request a scratch buffer that is more than 6 1589 ** times the database page size. 1590 ** ^If SQLite needs needs additional 1591 ** scratch memory beyond what is provided by this configuration option, then 1592 ** [sqlite3_malloc()] will be used to obtain the memory needed.<p> 1593 ** ^When the application provides any amount of scratch memory using 1594 ** SQLITE_CONFIG_SCRATCH, SQLite avoids unnecessary large 1595 ** [sqlite3_malloc|heap allocations]. 1596 ** This can help [Robson proof|prevent memory allocation failures] due to heap 1597 ** fragmentation in low-memory embedded systems. 1598 ** </dd> 1599 ** 1600 ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> 1601 ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a static memory buffer 1602 ** that SQLite can use for the database page cache with the default page 1603 ** cache implementation. 1604 ** This configuration should not be used if an application-define page 1605 ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2] 1606 ** configuration option. 1607 ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to 1608 ** 8-byte aligned 1609 ** memory, the size of each page buffer (sz), and the number of pages (N). 1610 ** The sz argument should be the size of the largest database page 1611 ** (a power of two between 512 and 65536) plus some extra bytes for each 1612 ** page header. ^The number of extra bytes needed by the page header 1613 ** can be determined using the [SQLITE_CONFIG_PCACHE_HDRSZ] option 1614 ** to [sqlite3_config()]. 1615 ** ^It is harmless, apart from the wasted memory, 1616 ** for the sz parameter to be larger than necessary. The first 1617 ** argument should pointer to an 8-byte aligned block of memory that 1618 ** is at least sz*N bytes of memory, otherwise subsequent behavior is 1619 ** undefined. 1620 ** ^SQLite will use the memory provided by the first argument to satisfy its 1621 ** memory needs for the first N pages that it adds to cache. ^If additional 1622 ** page cache memory is needed beyond what is provided by this option, then 1623 ** SQLite goes to [sqlite3_malloc()] for the additional storage space.</dd> 1624 ** 1625 ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> 1626 ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 1627 ** that SQLite will use for all of its dynamic memory allocation needs 1628 ** beyond those provided for by [SQLITE_CONFIG_SCRATCH] and 1629 ** [SQLITE_CONFIG_PAGECACHE]. 1630 ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled 1631 ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns 1632 ** [SQLITE_ERROR] if invoked otherwise. 1633 ** ^There are three arguments to SQLITE_CONFIG_HEAP: 1634 ** An 8-byte aligned pointer to the memory, 1635 ** the number of bytes in the memory buffer, and the minimum allocation size. 1636 ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts 1637 ** to using its default memory allocator (the system malloc() implementation), 1638 ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the 1639 ** memory pointer is not NULL then the alternative memory 1640 ** allocator is engaged to handle all of SQLites memory allocation needs. 1641 ** The first pointer (the memory pointer) must be aligned to an 8-byte 1642 ** boundary or subsequent behavior of SQLite will be undefined. 1643 ** The minimum allocation size is capped at 2**12. Reasonable values 1644 ** for the minimum allocation size are 2**5 through 2**8.</dd> 1645 ** 1646 ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> 1647 ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a 1648 ** pointer to an instance of the [sqlite3_mutex_methods] structure. 1649 ** The argument specifies alternative low-level mutex routines to be used 1650 ** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of 1651 ** the content of the [sqlite3_mutex_methods] structure before the call to 1652 ** [sqlite3_config()] returns. ^If SQLite is compiled with 1653 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1654 ** the entire mutexing subsystem is omitted from the build and hence calls to 1655 ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will 1656 ** return [SQLITE_ERROR].</dd> 1657 ** 1658 ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> 1659 ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which 1660 ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The 1661 ** [sqlite3_mutex_methods] 1662 ** structure is filled with the currently defined mutex routines.)^ 1663 ** This option can be used to overload the default mutex allocation 1664 ** routines with a wrapper used to track mutex usage for performance 1665 ** profiling or testing, for example. ^If SQLite is compiled with 1666 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1667 ** the entire mutexing subsystem is omitted from the build and hence calls to 1668 ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will 1669 ** return [SQLITE_ERROR].</dd> 1670 ** 1671 ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> 1672 ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine 1673 ** the default size of lookaside memory on each [database connection]. 1674 ** The first argument is the 1675 ** size of each lookaside buffer slot and the second is the number of 1676 ** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE 1677 ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] 1678 ** option to [sqlite3_db_config()] can be used to change the lookaside 1679 ** configuration on individual connections.)^ </dd> 1680 ** 1681 ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> 1682 ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 1683 ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies 1684 ** the interface to a custom page cache implementation.)^ 1685 ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> 1686 ** 1687 ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> 1688 ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which 1689 ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of 1690 ** the current page cache implementation into that object.)^ </dd> 1691 ** 1692 ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> 1693 ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite 1694 ** global [error log]. 1695 ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a 1696 ** function with a call signature of void(*)(void*,int,const char*), 1697 ** and a pointer to void. ^If the function pointer is not NULL, it is 1698 ** invoked by [sqlite3_log()] to process each logging event. ^If the 1699 ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. 1700 ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is 1701 ** passed through as the first parameter to the application-defined logger 1702 ** function whenever that function is invoked. ^The second parameter to 1703 ** the logger function is a copy of the first parameter to the corresponding 1704 ** [sqlite3_log()] call and is intended to be a [result code] or an 1705 ** [extended result code]. ^The third parameter passed to the logger is 1706 ** log message after formatting via [sqlite3_snprintf()]. 1707 ** The SQLite logging interface is not reentrant; the logger function 1708 ** supplied by the application must not invoke any SQLite interface. 1709 ** In a multi-threaded application, the application-defined logger 1710 ** function must be threadsafe. </dd> 1711 ** 1712 ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI 1713 ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. 1714 ** If non-zero, then URI handling is globally enabled. If the parameter is zero, 1715 ** then URI handling is globally disabled.)^ ^If URI handling is globally 1716 ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], 1717 ** [sqlite3_open16()] or 1718 ** specified as part of [ATTACH] commands are interpreted as URIs, regardless 1719 ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database 1720 ** connection is opened. ^If it is globally disabled, filenames are 1721 ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the 1722 ** database connection is opened. ^(By default, URI handling is globally 1723 ** disabled. The default value may be changed by compiling with the 1724 ** [SQLITE_USE_URI] symbol defined.)^ 1725 ** 1726 ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN 1727 ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer 1728 ** argument which is interpreted as a boolean in order to enable or disable 1729 ** the use of covering indices for full table scans in the query optimizer. 1730 ** ^The default setting is determined 1731 ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" 1732 ** if that compile-time option is omitted. 1733 ** The ability to disable the use of covering indices for full table scans 1734 ** is because some incorrectly coded legacy applications might malfunction 1735 ** when the optimization is enabled. Providing the ability to 1736 ** disable the optimization allows the older, buggy application code to work 1737 ** without change even with newer versions of SQLite. 1738 ** 1739 ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] 1740 ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE 1741 ** <dd> These options are obsolete and should not be used by new code. 1742 ** They are retained for backwards compatibility but are now no-ops. 1743 ** </dd> 1744 ** 1745 ** [[SQLITE_CONFIG_SQLLOG]] 1746 ** <dt>SQLITE_CONFIG_SQLLOG 1747 ** <dd>This option is only available if sqlite is compiled with the 1748 ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should 1749 ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). 1750 ** The second should be of type (void*). The callback is invoked by the library 1751 ** in three separate circumstances, identified by the value passed as the 1752 ** fourth parameter. If the fourth parameter is 0, then the database connection 1753 ** passed as the second argument has just been opened. The third argument 1754 ** points to a buffer containing the name of the main database file. If the 1755 ** fourth parameter is 1, then the SQL statement that the third parameter 1756 ** points to has just been executed. Or, if the fourth parameter is 2, then 1757 ** the connection being passed as the second parameter is being closed. The 1758 ** third parameter is passed NULL In this case. An example of using this 1759 ** configuration option can be seen in the "test_sqllog.c" source file in 1760 ** the canonical SQLite source tree.</dd> 1761 ** 1762 ** [[SQLITE_CONFIG_MMAP_SIZE]] 1763 ** <dt>SQLITE_CONFIG_MMAP_SIZE 1764 ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values 1765 ** that are the default mmap size limit (the default setting for 1766 ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. 1767 ** ^The default setting can be overridden by each database connection using 1768 ** either the [PRAGMA mmap_size] command, or by using the 1769 ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size 1770 ** will be silently truncated if necessary so that it does not exceed the 1771 ** compile-time maximum mmap size set by the 1772 ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ 1773 ** ^If either argument to this option is negative, then that argument is 1774 ** changed to its compile-time default. 1775 ** 1776 ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] 1777 ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE 1778 ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is 1779 ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro 1780 ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value 1781 ** that specifies the maximum size of the created heap. 1782 ** 1783 ** [[SQLITE_CONFIG_PCACHE_HDRSZ]] 1784 ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ 1785 ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which 1786 ** is a pointer to an integer and writes into that integer the number of extra 1787 ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. 1788 ** The amount of extra space required can change depending on the compiler, 1789 ** target platform, and SQLite version. 1790 ** 1791 ** [[SQLITE_CONFIG_PMASZ]] 1792 ** <dt>SQLITE_CONFIG_PMASZ 1793 ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which 1794 ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded 1795 ** sorter to that integer. The default minimum PMA Size is set by the 1796 ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched 1797 ** to help with sort operations when multithreaded sorting 1798 ** is enabled (using the [PRAGMA threads] command) and the amount of content 1799 ** to be sorted exceeds the page size times the minimum of the 1800 ** [PRAGMA cache_size] setting and this value. 1801 ** </dl> 1802 */ 1803 #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ 1804 #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ 1805 #define SQLITE_CONFIG_SERIALIZED 3 /* nil */ 1806 #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ 1807 #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ 1808 #define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */ 1809 #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ 1810 #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ 1811 #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ 1812 #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ 1813 #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ 1814 /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 1815 #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ 1816 #define SQLITE_CONFIG_PCACHE 14 /* no-op */ 1817 #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ 1818 #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ 1819 #define SQLITE_CONFIG_URI 17 /* int */ 1820 #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ 1821 #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ 1822 #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ 1823 #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ 1824 #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ 1825 #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ 1826 #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ 1827 #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ 1828 1829 /* 1830 ** CAPI3REF: Database Connection Configuration Options 1831 ** 1832 ** These constants are the available integer configuration options that 1833 ** can be passed as the second argument to the [sqlite3_db_config()] interface. 1834 ** 1835 ** New configuration options may be added in future releases of SQLite. 1836 ** Existing configuration options might be discontinued. Applications 1837 ** should check the return code from [sqlite3_db_config()] to make sure that 1838 ** the call worked. ^The [sqlite3_db_config()] interface will return a 1839 ** non-zero [error code] if a discontinued or unsupported configuration option 1840 ** is invoked. 1841 ** 1842 ** <dl> 1843 ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> 1844 ** <dd> ^This option takes three additional arguments that determine the 1845 ** [lookaside memory allocator] configuration for the [database connection]. 1846 ** ^The first argument (the third parameter to [sqlite3_db_config()] is a 1847 ** pointer to a memory buffer to use for lookaside memory. 1848 ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb 1849 ** may be NULL in which case SQLite will allocate the 1850 ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the 1851 ** size of each lookaside buffer slot. ^The third argument is the number of 1852 ** slots. The size of the buffer in the first argument must be greater than 1853 ** or equal to the product of the second and third arguments. The buffer 1854 ** must be aligned to an 8-byte boundary. ^If the second argument to 1855 ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally 1856 ** rounded down to the next smaller multiple of 8. ^(The lookaside memory 1857 ** configuration for a database connection can only be changed when that 1858 ** connection is not currently using lookaside memory, or in other words 1859 ** when the "current value" returned by 1860 ** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. 1861 ** Any attempt to change the lookaside memory configuration when lookaside 1862 ** memory is in use leaves the configuration unchanged and returns 1863 ** [SQLITE_BUSY].)^</dd> 1864 ** 1865 ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> 1866 ** <dd> ^This option is used to enable or disable the enforcement of 1867 ** [foreign key constraints]. There should be two additional arguments. 1868 ** The first argument is an integer which is 0 to disable FK enforcement, 1869 ** positive to enable FK enforcement or negative to leave FK enforcement 1870 ** unchanged. The second parameter is a pointer to an integer into which 1871 ** is written 0 or 1 to indicate whether FK enforcement is off or on 1872 ** following this call. The second parameter may be a NULL pointer, in 1873 ** which case the FK enforcement setting is not reported back. </dd> 1874 ** 1875 ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> 1876 ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. 1877 ** There should be two additional arguments. 1878 ** The first argument is an integer which is 0 to disable triggers, 1879 ** positive to enable triggers or negative to leave the setting unchanged. 1880 ** The second parameter is a pointer to an integer into which 1881 ** is written 0 or 1 to indicate whether triggers are disabled or enabled 1882 ** following this call. The second parameter may be a NULL pointer, in 1883 ** which case the trigger setting is not reported back. </dd> 1884 ** 1885 ** </dl> 1886 */ 1887 #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ 1888 #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ 1889 #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ 1890 1891 1892 /* 1893 ** CAPI3REF: Enable Or Disable Extended Result Codes 1894 ** METHOD: sqlite3 1895 ** 1896 ** ^The sqlite3_extended_result_codes() routine enables or disables the 1897 ** [extended result codes] feature of SQLite. ^The extended result 1898 ** codes are disabled by default for historical compatibility. 1899 */ 1900 SQLITE_API int SQLITE_STDCALL sqlite3_extended_result_codes(sqlite3*, int onoff); 1901 1902 /* 1903 ** CAPI3REF: Last Insert Rowid 1904 ** METHOD: sqlite3 1905 ** 1906 ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) 1907 ** has a unique 64-bit signed 1908 ** integer key called the [ROWID | "rowid"]. ^The rowid is always available 1909 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those 1910 ** names are not also used by explicitly declared columns. ^If 1911 ** the table has a column of type [INTEGER PRIMARY KEY] then that column 1912 ** is another alias for the rowid. 1913 ** 1914 ** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the 1915 ** most recent successful [INSERT] into a rowid table or [virtual table] 1916 ** on database connection D. 1917 ** ^Inserts into [WITHOUT ROWID] tables are not recorded. 1918 ** ^If no successful [INSERT]s into rowid tables 1919 ** have ever occurred on the database connection D, 1920 ** then sqlite3_last_insert_rowid(D) returns zero. 1921 ** 1922 ** ^(If an [INSERT] occurs within a trigger or within a [virtual table] 1923 ** method, then this routine will return the [rowid] of the inserted 1924 ** row as long as the trigger or virtual table method is running. 1925 ** But once the trigger or virtual table method ends, the value returned 1926 ** by this routine reverts to what it was before the trigger or virtual 1927 ** table method began.)^ 1928 ** 1929 ** ^An [INSERT] that fails due to a constraint violation is not a 1930 ** successful [INSERT] and does not change the value returned by this 1931 ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, 1932 ** and INSERT OR ABORT make no changes to the return value of this 1933 ** routine when their insertion fails. ^(When INSERT OR REPLACE 1934 ** encounters a constraint violation, it does not fail. The 1935 ** INSERT continues to completion after deleting rows that caused 1936 ** the constraint problem so INSERT OR REPLACE will always change 1937 ** the return value of this interface.)^ 1938 ** 1939 ** ^For the purposes of this routine, an [INSERT] is considered to 1940 ** be successful even if it is subsequently rolled back. 1941 ** 1942 ** This function is accessible to SQL statements via the 1943 ** [last_insert_rowid() SQL function]. 1944 ** 1945 ** If a separate thread performs a new [INSERT] on the same 1946 ** database connection while the [sqlite3_last_insert_rowid()] 1947 ** function is running and thus changes the last insert [rowid], 1948 ** then the value returned by [sqlite3_last_insert_rowid()] is 1949 ** unpredictable and might not equal either the old or the new 1950 ** last insert [rowid]. 1951 */ 1952 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_last_insert_rowid(sqlite3*); 1953 1954 /* 1955 ** CAPI3REF: Count The Number Of Rows Modified 1956 ** METHOD: sqlite3 1957 ** 1958 ** ^This function returns the number of rows modified, inserted or 1959 ** deleted by the most recently completed INSERT, UPDATE or DELETE 1960 ** statement on the database connection specified by the only parameter. 1961 ** ^Executing any other type of SQL statement does not modify the value 1962 ** returned by this function. 1963 ** 1964 ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are 1965 ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 1966 ** [foreign key actions] or [REPLACE] constraint resolution are not counted. 1967 ** 1968 ** Changes to a view that are intercepted by 1969 ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 1970 ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 1971 ** DELETE statement run on a view is always zero. Only changes made to real 1972 ** tables are counted. 1973 ** 1974 ** Things are more complicated if the sqlite3_changes() function is 1975 ** executed while a trigger program is running. This may happen if the 1976 ** program uses the [changes() SQL function], or if some other callback 1977 ** function invokes sqlite3_changes() directly. Essentially: 1978 ** 1979 ** <ul> 1980 ** <li> ^(Before entering a trigger program the value returned by 1981 ** sqlite3_changes() function is saved. After the trigger program 1982 ** has finished, the original value is restored.)^ 1983 ** 1984 ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 1985 ** statement sets the value returned by sqlite3_changes() 1986 ** upon completion as normal. Of course, this value will not include 1987 ** any changes performed by sub-triggers, as the sqlite3_changes() 1988 ** value will be saved and restored after each sub-trigger has run.)^ 1989 ** </ul> 1990 ** 1991 ** ^This means that if the changes() SQL function (or similar) is used 1992 ** by the first INSERT, UPDATE or DELETE statement within a trigger, it 1993 ** returns the value as set when the calling statement began executing. 1994 ** ^If it is used by the second or subsequent such statement within a trigger 1995 ** program, the value returned reflects the number of rows modified by the 1996 ** previous INSERT, UPDATE or DELETE statement within the same trigger. 1997 ** 1998 ** See also the [sqlite3_total_changes()] interface, the 1999 ** [count_changes pragma], and the [changes() SQL function]. 2000 ** 2001 ** If a separate thread makes changes on the same database connection 2002 ** while [sqlite3_changes()] is running then the value returned 2003 ** is unpredictable and not meaningful. 2004 */ 2005 SQLITE_API int SQLITE_STDCALL sqlite3_changes(sqlite3*); 2006 2007 /* 2008 ** CAPI3REF: Total Number Of Rows Modified 2009 ** METHOD: sqlite3 2010 ** 2011 ** ^This function returns the total number of rows inserted, modified or 2012 ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed 2013 ** since the database connection was opened, including those executed as 2014 ** part of trigger programs. ^Executing any other type of SQL statement 2015 ** does not affect the value returned by sqlite3_total_changes(). 2016 ** 2017 ** ^Changes made as part of [foreign key actions] are included in the 2018 ** count, but those made as part of REPLACE constraint resolution are 2019 ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 2020 ** are not counted. 2021 ** 2022 ** See also the [sqlite3_changes()] interface, the 2023 ** [count_changes pragma], and the [total_changes() SQL function]. 2024 ** 2025 ** If a separate thread makes changes on the same database connection 2026 ** while [sqlite3_total_changes()] is running then the value 2027 ** returned is unpredictable and not meaningful. 2028 */ 2029 SQLITE_API int SQLITE_STDCALL sqlite3_total_changes(sqlite3*); 2030 2031 /* 2032 ** CAPI3REF: Interrupt A Long-Running Query 2033 ** METHOD: sqlite3 2034 ** 2035 ** ^This function causes any pending database operation to abort and 2036 ** return at its earliest opportunity. This routine is typically 2037 ** called in response to a user action such as pressing "Cancel" 2038 ** or Ctrl-C where the user wants a long query operation to halt 2039 ** immediately. 2040 ** 2041 ** ^It is safe to call this routine from a thread different from the 2042 ** thread that is currently running the database operation. But it 2043 ** is not safe to call this routine with a [database connection] that 2044 ** is closed or might close before sqlite3_interrupt() returns. 2045 ** 2046 ** ^If an SQL operation is very nearly finished at the time when 2047 ** sqlite3_interrupt() is called, then it might not have an opportunity 2048 ** to be interrupted and might continue to completion. 2049 ** 2050 ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. 2051 ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE 2052 ** that is inside an explicit transaction, then the entire transaction 2053 ** will be rolled back automatically. 2054 ** 2055 ** ^The sqlite3_interrupt(D) call is in effect until all currently running 2056 ** SQL statements on [database connection] D complete. ^Any new SQL statements 2057 ** that are started after the sqlite3_interrupt() call and before the 2058 ** running statements reaches zero are interrupted as if they had been 2059 ** running prior to the sqlite3_interrupt() call. ^New SQL statements 2060 ** that are started after the running statement count reaches zero are 2061 ** not effected by the sqlite3_interrupt(). 2062 ** ^A call to sqlite3_interrupt(D) that occurs when there are no running 2063 ** SQL statements is a no-op and has no effect on SQL statements 2064 ** that are started after the sqlite3_interrupt() call returns. 2065 ** 2066 ** If the database connection closes while [sqlite3_interrupt()] 2067 ** is running then bad things will likely happen. 2068 */ 2069 SQLITE_API void SQLITE_STDCALL sqlite3_interrupt(sqlite3*); 2070 2071 /* 2072 ** CAPI3REF: Determine If An SQL Statement Is Complete 2073 ** 2074 ** These routines are useful during command-line input to determine if the 2075 ** currently entered text seems to form a complete SQL statement or 2076 ** if additional input is needed before sending the text into 2077 ** SQLite for parsing. ^These routines return 1 if the input string 2078 ** appears to be a complete SQL statement. ^A statement is judged to be 2079 ** complete if it ends with a semicolon token and is not a prefix of a 2080 ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within 2081 ** string literals or quoted identifier names or comments are not 2082 ** independent tokens (they are part of the token in which they are 2083 ** embedded) and thus do not count as a statement terminator. ^Whitespace 2084 ** and comments that follow the final semicolon are ignored. 2085 ** 2086 ** ^These routines return 0 if the statement is incomplete. ^If a 2087 ** memory allocation fails, then SQLITE_NOMEM is returned. 2088 ** 2089 ** ^These routines do not parse the SQL statements thus 2090 ** will not detect syntactically incorrect SQL. 2091 ** 2092 ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 2093 ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked 2094 ** automatically by sqlite3_complete16(). If that initialization fails, 2095 ** then the return value from sqlite3_complete16() will be non-zero 2096 ** regardless of whether or not the input SQL is complete.)^ 2097 ** 2098 ** The input to [sqlite3_complete()] must be a zero-terminated 2099 ** UTF-8 string. 2100 ** 2101 ** The input to [sqlite3_complete16()] must be a zero-terminated 2102 ** UTF-16 string in native byte order. 2103 */ 2104 SQLITE_API int SQLITE_STDCALL sqlite3_complete(const char *sql); 2105 SQLITE_API int SQLITE_STDCALL sqlite3_complete16(const void *sql); 2106 2107 /* 2108 ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors 2109 ** KEYWORDS: {busy-handler callback} {busy handler} 2110 ** METHOD: sqlite3 2111 ** 2112 ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X 2113 ** that might be invoked with argument P whenever 2114 ** an attempt is made to access a database table associated with 2115 ** [database connection] D when another thread 2116 ** or process has the table locked. 2117 ** The sqlite3_busy_handler() interface is used to implement 2118 ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. 2119 ** 2120 ** ^If the busy callback is NULL, then [SQLITE_BUSY] 2121 ** is returned immediately upon encountering the lock. ^If the busy callback 2122 ** is not NULL, then the callback might be invoked with two arguments. 2123 ** 2124 ** ^The first argument to the busy handler is a copy of the void* pointer which 2125 ** is the third argument to sqlite3_busy_handler(). ^The second argument to 2126 ** the busy handler callback is the number of times that the busy handler has 2127 ** been invoked previously for the same locking event. ^If the 2128 ** busy callback returns 0, then no additional attempts are made to 2129 ** access the database and [SQLITE_BUSY] is returned 2130 ** to the application. 2131 ** ^If the callback returns non-zero, then another attempt 2132 ** is made to access the database and the cycle repeats. 2133 ** 2134 ** The presence of a busy handler does not guarantee that it will be invoked 2135 ** when there is lock contention. ^If SQLite determines that invoking the busy 2136 ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] 2137 ** to the application instead of invoking the 2138 ** busy handler. 2139 ** Consider a scenario where one process is holding a read lock that 2140 ** it is trying to promote to a reserved lock and 2141 ** a second process is holding a reserved lock that it is trying 2142 ** to promote to an exclusive lock. The first process cannot proceed 2143 ** because it is blocked by the second and the second process cannot 2144 ** proceed because it is blocked by the first. If both processes 2145 ** invoke the busy handlers, neither will make any progress. Therefore, 2146 ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this 2147 ** will induce the first process to release its read lock and allow 2148 ** the second process to proceed. 2149 ** 2150 ** ^The default busy callback is NULL. 2151 ** 2152 ** ^(There can only be a single busy handler defined for each 2153 ** [database connection]. Setting a new busy handler clears any 2154 ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] 2155 ** or evaluating [PRAGMA busy_timeout=N] will change the 2156 ** busy handler and thus clear any previously set busy handler. 2157 ** 2158 ** The busy callback should not take any actions which modify the 2159 ** database connection that invoked the busy handler. In other words, 2160 ** the busy handler is not reentrant. Any such actions 2161 ** result in undefined behavior. 2162 ** 2163 ** A busy handler must not close the database connection 2164 ** or [prepared statement] that invoked the busy handler. 2165 */ 2166 SQLITE_API int SQLITE_STDCALL sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*); 2167 2168 /* 2169 ** CAPI3REF: Set A Busy Timeout 2170 ** METHOD: sqlite3 2171 ** 2172 ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps 2173 ** for a specified amount of time when a table is locked. ^The handler 2174 ** will sleep multiple times until at least "ms" milliseconds of sleeping 2175 ** have accumulated. ^After at least "ms" milliseconds of sleeping, 2176 ** the handler returns 0 which causes [sqlite3_step()] to return 2177 ** [SQLITE_BUSY]. 2178 ** 2179 ** ^Calling this routine with an argument less than or equal to zero 2180 ** turns off all busy handlers. 2181 ** 2182 ** ^(There can only be a single busy handler for a particular 2183 ** [database connection] at any given moment. If another busy handler 2184 ** was defined (using [sqlite3_busy_handler()]) prior to calling 2185 ** this routine, that other busy handler is cleared.)^ 2186 ** 2187 ** See also: [PRAGMA busy_timeout] 2188 */ 2189 SQLITE_API int SQLITE_STDCALL sqlite3_busy_timeout(sqlite3*, int ms); 2190 2191 /* 2192 ** CAPI3REF: Convenience Routines For Running Queries 2193 ** METHOD: sqlite3 2194 ** 2195 ** This is a legacy interface that is preserved for backwards compatibility. 2196 ** Use of this interface is not recommended. 2197 ** 2198 ** Definition: A <b>result table</b> is memory data structure created by the 2199 ** [sqlite3_get_table()] interface. A result table records the 2200 ** complete query results from one or more queries. 2201 ** 2202 ** The table conceptually has a number of rows and columns. But 2203 ** these numbers are not part of the result table itself. These 2204 ** numbers are obtained separately. Let N be the number of rows 2205 ** and M be the number of columns. 2206 ** 2207 ** A result table is an array of pointers to zero-terminated UTF-8 strings. 2208 ** There are (N+1)*M elements in the array. The first M pointers point 2209 ** to zero-terminated strings that contain the names of the columns. 2210 ** The remaining entries all point to query results. NULL values result 2211 ** in NULL pointers. All other values are in their UTF-8 zero-terminated 2212 ** string representation as returned by [sqlite3_column_text()]. 2213 ** 2214 ** A result table might consist of one or more memory allocations. 2215 ** It is not safe to pass a result table directly to [sqlite3_free()]. 2216 ** A result table should be deallocated using [sqlite3_free_table()]. 2217 ** 2218 ** ^(As an example of the result table format, suppose a query result 2219 ** is as follows: 2220 ** 2221 ** <blockquote><pre> 2222 ** Name | Age 2223 ** ----------------------- 2224 ** Alice | 43 2225 ** Bob | 28 2226 ** Cindy | 21 2227 ** </pre></blockquote> 2228 ** 2229 ** There are two column (M==2) and three rows (N==3). Thus the 2230 ** result table has 8 entries. Suppose the result table is stored 2231 ** in an array names azResult. Then azResult holds this content: 2232 ** 2233 ** <blockquote><pre> 2234 ** azResult[0] = "Name"; 2235 ** azResult[1] = "Age"; 2236 ** azResult[2] = "Alice"; 2237 ** azResult[3] = "43"; 2238 ** azResult[4] = "Bob"; 2239 ** azResult[5] = "28"; 2240 ** azResult[6] = "Cindy"; 2241 ** azResult[7] = "21"; 2242 ** </pre></blockquote>)^ 2243 ** 2244 ** ^The sqlite3_get_table() function evaluates one or more 2245 ** semicolon-separated SQL statements in the zero-terminated UTF-8 2246 ** string of its 2nd parameter and returns a result table to the 2247 ** pointer given in its 3rd parameter. 2248 ** 2249 ** After the application has finished with the result from sqlite3_get_table(), 2250 ** it must pass the result table pointer to sqlite3_free_table() in order to 2251 ** release the memory that was malloced. Because of the way the 2252 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling 2253 ** function must not try to call [sqlite3_free()] directly. Only 2254 ** [sqlite3_free_table()] is able to release the memory properly and safely. 2255 ** 2256 ** The sqlite3_get_table() interface is implemented as a wrapper around 2257 ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access 2258 ** to any internal data structures of SQLite. It uses only the public 2259 ** interface defined here. As a consequence, errors that occur in the 2260 ** wrapper layer outside of the internal [sqlite3_exec()] call are not 2261 ** reflected in subsequent calls to [sqlite3_errcode()] or 2262 ** [sqlite3_errmsg()]. 2263 */ 2264 SQLITE_API int SQLITE_STDCALL sqlite3_get_table( 2265 sqlite3 *db, /* An open database */ 2266 const char *zSql, /* SQL to be evaluated */ 2267 char ***pazResult, /* Results of the query */ 2268 int *pnRow, /* Number of result rows written here */ 2269 int *pnColumn, /* Number of result columns written here */ 2270 char **pzErrmsg /* Error msg written here */ 2271 ); 2272 SQLITE_API void SQLITE_STDCALL sqlite3_free_table(char **result); 2273 2274 /* 2275 ** CAPI3REF: Formatted String Printing Functions 2276 ** 2277 ** These routines are work-alikes of the "printf()" family of functions 2278 ** from the standard C library. 2279 ** These routines understand most of the common K&R formatting options, 2280 ** plus some additional non-standard formats, detailed below. 2281 ** Note that some of the more obscure formatting options from recent 2282 ** C-library standards are omitted from this implementation. 2283 ** 2284 ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their 2285 ** results into memory obtained from [sqlite3_malloc()]. 2286 ** The strings returned by these two routines should be 2287 ** released by [sqlite3_free()]. ^Both routines return a 2288 ** NULL pointer if [sqlite3_malloc()] is unable to allocate enough 2289 ** memory to hold the resulting string. 2290 ** 2291 ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from 2292 ** the standard C library. The result is written into the 2293 ** buffer supplied as the second parameter whose size is given by 2294 ** the first parameter. Note that the order of the 2295 ** first two parameters is reversed from snprintf().)^ This is an 2296 ** historical accident that cannot be fixed without breaking 2297 ** backwards compatibility. ^(Note also that sqlite3_snprintf() 2298 ** returns a pointer to its buffer instead of the number of 2299 ** characters actually written into the buffer.)^ We admit that 2300 ** the number of characters written would be a more useful return 2301 ** value but we cannot change the implementation of sqlite3_snprintf() 2302 ** now without breaking compatibility. 2303 ** 2304 ** ^As long as the buffer size is greater than zero, sqlite3_snprintf() 2305 ** guarantees that the buffer is always zero-terminated. ^The first 2306 ** parameter "n" is the total size of the buffer, including space for 2307 ** the zero terminator. So the longest string that can be completely 2308 ** written will be n-1 characters. 2309 ** 2310 ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). 2311 ** 2312 ** These routines all implement some additional formatting 2313 ** options that are useful for constructing SQL statements. 2314 ** All of the usual printf() formatting options apply. In addition, there 2315 ** is are "%q", "%Q", "%w" and "%z" options. 2316 ** 2317 ** ^(The %q option works like %s in that it substitutes a nul-terminated 2318 ** string from the argument list. But %q also doubles every '\'' character. 2319 ** %q is designed for use inside a string literal.)^ By doubling each '\'' 2320 ** character it escapes that character and allows it to be inserted into 2321 ** the string. 2322 ** 2323 ** For example, assume the string variable zText contains text as follows: 2324 ** 2325 ** <blockquote><pre> 2326 ** char *zText = "It's a happy day!"; 2327 ** </pre></blockquote> 2328 ** 2329 ** One can use this text in an SQL statement as follows: 2330 ** 2331 ** <blockquote><pre> 2332 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText); 2333 ** sqlite3_exec(db, zSQL, 0, 0, 0); 2334 ** sqlite3_free(zSQL); 2335 ** </pre></blockquote> 2336 ** 2337 ** Because the %q format string is used, the '\'' character in zText 2338 ** is escaped and the SQL generated is as follows: 2339 ** 2340 ** <blockquote><pre> 2341 ** INSERT INTO table1 VALUES('It''s a happy day!') 2342 ** </pre></blockquote> 2343 ** 2344 ** This is correct. Had we used %s instead of %q, the generated SQL 2345 ** would have looked like this: 2346 ** 2347 ** <blockquote><pre> 2348 ** INSERT INTO table1 VALUES('It's a happy day!'); 2349 ** </pre></blockquote> 2350 ** 2351 ** This second example is an SQL syntax error. As a general rule you should 2352 ** always use %q instead of %s when inserting text into a string literal. 2353 ** 2354 ** ^(The %Q option works like %q except it also adds single quotes around 2355 ** the outside of the total string. Additionally, if the parameter in the 2356 ** argument list is a NULL pointer, %Q substitutes the text "NULL" (without 2357 ** single quotes).)^ So, for example, one could say: 2358 ** 2359 ** <blockquote><pre> 2360 ** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText); 2361 ** sqlite3_exec(db, zSQL, 0, 0, 0); 2362 ** sqlite3_free(zSQL); 2363 ** </pre></blockquote> 2364 ** 2365 ** The code above will render a correct SQL statement in the zSQL 2366 ** variable even if the zText variable is a NULL pointer. 2367 ** 2368 ** ^(The "%w" formatting option is like "%q" except that it expects to 2369 ** be contained within double-quotes instead of single quotes, and it 2370 ** escapes the double-quote character instead of the single-quote 2371 ** character.)^ The "%w" formatting option is intended for safely inserting 2372 ** table and column names into a constructed SQL statement. 2373 ** 2374 ** ^(The "%z" formatting option works like "%s" but with the 2375 ** addition that after the string has been read and copied into 2376 ** the result, [sqlite3_free()] is called on the input string.)^ 2377 */ 2378 SQLITE_API char *SQLITE_CDECL sqlite3_mprintf(const char*,...); 2379 SQLITE_API char *SQLITE_STDCALL sqlite3_vmprintf(const char*, va_list); 2380 SQLITE_API char *SQLITE_CDECL sqlite3_snprintf(int,char*,const char*, ...); 2381 SQLITE_API char *SQLITE_STDCALL sqlite3_vsnprintf(int,char*,const char*, va_list); 2382 2383 /* 2384 ** CAPI3REF: Memory Allocation Subsystem 2385 ** 2386 ** The SQLite core uses these three routines for all of its own 2387 ** internal memory allocation needs. "Core" in the previous sentence 2388 ** does not include operating-system specific VFS implementation. The 2389 ** Windows VFS uses native malloc() and free() for some operations. 2390 ** 2391 ** ^The sqlite3_malloc() routine returns a pointer to a block 2392 ** of memory at least N bytes in length, where N is the parameter. 2393 ** ^If sqlite3_malloc() is unable to obtain sufficient free 2394 ** memory, it returns a NULL pointer. ^If the parameter N to 2395 ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns 2396 ** a NULL pointer. 2397 ** 2398 ** ^The sqlite3_malloc64(N) routine works just like 2399 ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead 2400 ** of a signed 32-bit integer. 2401 ** 2402 ** ^Calling sqlite3_free() with a pointer previously returned 2403 ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so 2404 ** that it might be reused. ^The sqlite3_free() routine is 2405 ** a no-op if is called with a NULL pointer. Passing a NULL pointer 2406 ** to sqlite3_free() is harmless. After being freed, memory 2407 ** should neither be read nor written. Even reading previously freed 2408 ** memory might result in a segmentation fault or other severe error. 2409 ** Memory corruption, a segmentation fault, or other severe error 2410 ** might result if sqlite3_free() is called with a non-NULL pointer that 2411 ** was not obtained from sqlite3_malloc() or sqlite3_realloc(). 2412 ** 2413 ** ^The sqlite3_realloc(X,N) interface attempts to resize a 2414 ** prior memory allocation X to be at least N bytes. 2415 ** ^If the X parameter to sqlite3_realloc(X,N) 2416 ** is a NULL pointer then its behavior is identical to calling 2417 ** sqlite3_malloc(N). 2418 ** ^If the N parameter to sqlite3_realloc(X,N) is zero or 2419 ** negative then the behavior is exactly the same as calling 2420 ** sqlite3_free(X). 2421 ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation 2422 ** of at least N bytes in size or NULL if insufficient memory is available. 2423 ** ^If M is the size of the prior allocation, then min(N,M) bytes 2424 ** of the prior allocation are copied into the beginning of buffer returned 2425 ** by sqlite3_realloc(X,N) and the prior allocation is freed. 2426 ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the 2427 ** prior allocation is not freed. 2428 ** 2429 ** ^The sqlite3_realloc64(X,N) interfaces works the same as 2430 ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead 2431 ** of a 32-bit signed integer. 2432 ** 2433 ** ^If X is a memory allocation previously obtained from sqlite3_malloc(), 2434 ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then 2435 ** sqlite3_msize(X) returns the size of that memory allocation in bytes. 2436 ** ^The value returned by sqlite3_msize(X) might be larger than the number 2437 ** of bytes requested when X was allocated. ^If X is a NULL pointer then 2438 ** sqlite3_msize(X) returns zero. If X points to something that is not 2439 ** the beginning of memory allocation, or if it points to a formerly 2440 ** valid memory allocation that has now been freed, then the behavior 2441 ** of sqlite3_msize(X) is undefined and possibly harmful. 2442 ** 2443 ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), 2444 ** sqlite3_malloc64(), and sqlite3_realloc64() 2445 ** is always aligned to at least an 8 byte boundary, or to a 2446 ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time 2447 ** option is used. 2448 ** 2449 ** In SQLite version 3.5.0 and 3.5.1, it was possible to define 2450 ** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in 2451 ** implementation of these routines to be omitted. That capability 2452 ** is no longer provided. Only built-in memory allocators can be used. 2453 ** 2454 ** Prior to SQLite version 3.7.10, the Windows OS interface layer called 2455 ** the system malloc() and free() directly when converting 2456 ** filenames between the UTF-8 encoding used by SQLite 2457 ** and whatever filename encoding is used by the particular Windows 2458 ** installation. Memory allocation errors were detected, but 2459 ** they were reported back as [SQLITE_CANTOPEN] or 2460 ** [SQLITE_IOERR] rather than [SQLITE_NOMEM]. 2461 ** 2462 ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] 2463 ** must be either NULL or else pointers obtained from a prior 2464 ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have 2465 ** not yet been released. 2466 ** 2467 ** The application must not read or write any part of 2468 ** a block of memory after it has been released using 2469 ** [sqlite3_free()] or [sqlite3_realloc()]. 2470 */ 2471 SQLITE_API void *SQLITE_STDCALL sqlite3_malloc(int); 2472 SQLITE_API void *SQLITE_STDCALL sqlite3_malloc64(sqlite3_uint64); 2473 SQLITE_API void *SQLITE_STDCALL sqlite3_realloc(void*, int); 2474 SQLITE_API void *SQLITE_STDCALL sqlite3_realloc64(void*, sqlite3_uint64); 2475 SQLITE_API void SQLITE_STDCALL sqlite3_free(void*); 2476 SQLITE_API sqlite3_uint64 SQLITE_STDCALL sqlite3_msize(void*); 2477 2478 /* 2479 ** CAPI3REF: Memory Allocator Statistics 2480 ** 2481 ** SQLite provides these two interfaces for reporting on the status 2482 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] 2483 ** routines, which form the built-in memory allocation subsystem. 2484 ** 2485 ** ^The [sqlite3_memory_used()] routine returns the number of bytes 2486 ** of memory currently outstanding (malloced but not freed). 2487 ** ^The [sqlite3_memory_highwater()] routine returns the maximum 2488 ** value of [sqlite3_memory_used()] since the high-water mark 2489 ** was last reset. ^The values returned by [sqlite3_memory_used()] and 2490 ** [sqlite3_memory_highwater()] include any overhead 2491 ** added by SQLite in its implementation of [sqlite3_malloc()], 2492 ** but not overhead added by the any underlying system library 2493 ** routines that [sqlite3_malloc()] may call. 2494 ** 2495 ** ^The memory high-water mark is reset to the current value of 2496 ** [sqlite3_memory_used()] if and only if the parameter to 2497 ** [sqlite3_memory_highwater()] is true. ^The value returned 2498 ** by [sqlite3_memory_highwater(1)] is the high-water mark 2499 ** prior to the reset. 2500 */ 2501 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_memory_used(void); 2502 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_memory_highwater(int resetFlag); 2503 2504 /* 2505 ** CAPI3REF: Pseudo-Random Number Generator 2506 ** 2507 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to 2508 ** select random [ROWID | ROWIDs] when inserting new records into a table that 2509 ** already uses the largest possible [ROWID]. The PRNG is also used for 2510 ** the build-in random() and randomblob() SQL functions. This interface allows 2511 ** applications to access the same PRNG for other purposes. 2512 ** 2513 ** ^A call to this routine stores N bytes of randomness into buffer P. 2514 ** ^The P parameter can be a NULL pointer. 2515 ** 2516 ** ^If this routine has not been previously called or if the previous 2517 ** call had N less than one or a NULL pointer for P, then the PRNG is 2518 ** seeded using randomness obtained from the xRandomness method of 2519 ** the default [sqlite3_vfs] object. 2520 ** ^If the previous call to this routine had an N of 1 or more and a 2521 ** non-NULL P then the pseudo-randomness is generated 2522 ** internally and without recourse to the [sqlite3_vfs] xRandomness 2523 ** method. 2524 */ 2525 SQLITE_API void SQLITE_STDCALL sqlite3_randomness(int N, void *P); 2526 2527 /* 2528 ** CAPI3REF: Compile-Time Authorization Callbacks 2529 ** METHOD: sqlite3 2530 ** 2531 ** ^This routine registers an authorizer callback with a particular 2532 ** [database connection], supplied in the first argument. 2533 ** ^The authorizer callback is invoked as SQL statements are being compiled 2534 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], 2535 ** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various 2536 ** points during the compilation process, as logic is being created 2537 ** to perform various actions, the authorizer callback is invoked to 2538 ** see if those actions are allowed. ^The authorizer callback should 2539 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the 2540 ** specific action but allow the SQL statement to continue to be 2541 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be 2542 ** rejected with an error. ^If the authorizer callback returns 2543 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] 2544 ** then the [sqlite3_prepare_v2()] or equivalent call that triggered 2545 ** the authorizer will fail with an error message. 2546 ** 2547 ** When the callback returns [SQLITE_OK], that means the operation 2548 ** requested is ok. ^When the callback returns [SQLITE_DENY], the 2549 ** [sqlite3_prepare_v2()] or equivalent call that triggered the 2550 ** authorizer will fail with an error message explaining that 2551 ** access is denied. 2552 ** 2553 ** ^The first parameter to the authorizer callback is a copy of the third 2554 ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter 2555 ** to the callback is an integer [SQLITE_COPY | action code] that specifies 2556 ** the particular action to be authorized. ^The third through sixth parameters 2557 ** to the callback are zero-terminated strings that contain additional 2558 ** details about the action to be authorized. 2559 ** 2560 ** ^If the action code is [SQLITE_READ] 2561 ** and the callback returns [SQLITE_IGNORE] then the 2562 ** [prepared statement] statement is constructed to substitute 2563 ** a NULL value in place of the table column that would have 2564 ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] 2565 ** return can be used to deny an untrusted user access to individual 2566 ** columns of a table. 2567 ** ^If the action code is [SQLITE_DELETE] and the callback returns 2568 ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the 2569 ** [truncate optimization] is disabled and all rows are deleted individually. 2570 ** 2571 ** An authorizer is used when [sqlite3_prepare | preparing] 2572 ** SQL statements from an untrusted source, to ensure that the SQL statements 2573 ** do not try to access data they are not allowed to see, or that they do not 2574 ** try to execute malicious statements that damage the database. For 2575 ** example, an application may allow a user to enter arbitrary 2576 ** SQL queries for evaluation by a database. But the application does 2577 ** not want the user to be able to make arbitrary changes to the 2578 ** database. An authorizer could then be put in place while the 2579 ** user-entered SQL is being [sqlite3_prepare | prepared] that 2580 ** disallows everything except [SELECT] statements. 2581 ** 2582 ** Applications that need to process SQL from untrusted sources 2583 ** might also consider lowering resource limits using [sqlite3_limit()] 2584 ** and limiting database size using the [max_page_count] [PRAGMA] 2585 ** in addition to using an authorizer. 2586 ** 2587 ** ^(Only a single authorizer can be in place on a database connection 2588 ** at a time. Each call to sqlite3_set_authorizer overrides the 2589 ** previous call.)^ ^Disable the authorizer by installing a NULL callback. 2590 ** The authorizer is disabled by default. 2591 ** 2592 ** The authorizer callback must not do anything that will modify 2593 ** the database connection that invoked the authorizer callback. 2594 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 2595 ** database connections for the meaning of "modify" in this paragraph. 2596 ** 2597 ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the 2598 ** statement might be re-prepared during [sqlite3_step()] due to a 2599 ** schema change. Hence, the application should ensure that the 2600 ** correct authorizer callback remains in place during the [sqlite3_step()]. 2601 ** 2602 ** ^Note that the authorizer callback is invoked only during 2603 ** [sqlite3_prepare()] or its variants. Authorization is not 2604 ** performed during statement evaluation in [sqlite3_step()], unless 2605 ** as stated in the previous paragraph, sqlite3_step() invokes 2606 ** sqlite3_prepare_v2() to reprepare a statement after a schema change. 2607 */ 2608 SQLITE_API int SQLITE_STDCALL sqlite3_set_authorizer( 2609 sqlite3*, 2610 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 2611 void *pUserData 2612 ); 2613 2614 /* 2615 ** CAPI3REF: Authorizer Return Codes 2616 ** 2617 ** The [sqlite3_set_authorizer | authorizer callback function] must 2618 ** return either [SQLITE_OK] or one of these two constants in order 2619 ** to signal SQLite whether or not the action is permitted. See the 2620 ** [sqlite3_set_authorizer | authorizer documentation] for additional 2621 ** information. 2622 ** 2623 ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] 2624 ** returned from the [sqlite3_vtab_on_conflict()] interface. 2625 */ 2626 #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 2627 #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 2628 2629 /* 2630 ** CAPI3REF: Authorizer Action Codes 2631 ** 2632 ** The [sqlite3_set_authorizer()] interface registers a callback function 2633 ** that is invoked to authorize certain SQL statement actions. The 2634 ** second parameter to the callback is an integer code that specifies 2635 ** what action is being authorized. These are the integer action codes that 2636 ** the authorizer callback may be passed. 2637 ** 2638 ** These action code values signify what kind of operation is to be 2639 ** authorized. The 3rd and 4th parameters to the authorization 2640 ** callback function will be parameters or NULL depending on which of these 2641 ** codes is used as the second parameter. ^(The 5th parameter to the 2642 ** authorizer callback is the name of the database ("main", "temp", 2643 ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback 2644 ** is the name of the inner-most trigger or view that is responsible for 2645 ** the access attempt or NULL if this access attempt is directly from 2646 ** top-level SQL code. 2647 */ 2648 /******************************************* 3rd ************ 4th ***********/ 2649 #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 2650 #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 2651 #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 2652 #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 2653 #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 2654 #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 2655 #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 2656 #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 2657 #define SQLITE_DELETE 9 /* Table Name NULL */ 2658 #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 2659 #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 2660 #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 2661 #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 2662 #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 2663 #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 2664 #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 2665 #define SQLITE_DROP_VIEW 17 /* View Name NULL */ 2666 #define SQLITE_INSERT 18 /* Table Name NULL */ 2667 #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 2668 #define SQLITE_READ 20 /* Table Name Column Name */ 2669 #define SQLITE_SELECT 21 /* NULL NULL */ 2670 #define SQLITE_TRANSACTION 22 /* Operation NULL */ 2671 #define SQLITE_UPDATE 23 /* Table Name Column Name */ 2672 #define SQLITE_ATTACH 24 /* Filename NULL */ 2673 #define SQLITE_DETACH 25 /* Database Name NULL */ 2674 #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ 2675 #define SQLITE_REINDEX 27 /* Index Name NULL */ 2676 #define SQLITE_ANALYZE 28 /* Table Name NULL */ 2677 #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ 2678 #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ 2679 #define SQLITE_FUNCTION 31 /* NULL Function Name */ 2680 #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ 2681 #define SQLITE_COPY 0 /* No longer used */ 2682 #define SQLITE_RECURSIVE 33 /* NULL NULL */ 2683 2684 /* 2685 ** CAPI3REF: Tracing And Profiling Functions 2686 ** METHOD: sqlite3 2687 ** 2688 ** These routines register callback functions that can be used for 2689 ** tracing and profiling the execution of SQL statements. 2690 ** 2691 ** ^The callback function registered by sqlite3_trace() is invoked at 2692 ** various times when an SQL statement is being run by [sqlite3_step()]. 2693 ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the 2694 ** SQL statement text as the statement first begins executing. 2695 ** ^(Additional sqlite3_trace() callbacks might occur 2696 ** as each triggered subprogram is entered. The callbacks for triggers 2697 ** contain a UTF-8 SQL comment that identifies the trigger.)^ 2698 ** 2699 ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit 2700 ** the length of [bound parameter] expansion in the output of sqlite3_trace(). 2701 ** 2702 ** ^The callback function registered by sqlite3_profile() is invoked 2703 ** as each SQL statement finishes. ^The profile callback contains 2704 ** the original statement text and an estimate of wall-clock time 2705 ** of how long that statement took to run. ^The profile callback 2706 ** time is in units of nanoseconds, however the current implementation 2707 ** is only capable of millisecond resolution so the six least significant 2708 ** digits in the time are meaningless. Future versions of SQLite 2709 ** might provide greater resolution on the profiler callback. The 2710 ** sqlite3_profile() function is considered experimental and is 2711 ** subject to change in future versions of SQLite. 2712 */ 2713 SQLITE_API void *SQLITE_STDCALL sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*); 2714 SQLITE_API SQLITE_EXPERIMENTAL void *SQLITE_STDCALL sqlite3_profile(sqlite3*, 2715 void(*xProfile)(void*,const char*,sqlite3_uint64), void*); 2716 2717 /* 2718 ** CAPI3REF: Query Progress Callbacks 2719 ** METHOD: sqlite3 2720 ** 2721 ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback 2722 ** function X to be invoked periodically during long running calls to 2723 ** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for 2724 ** database connection D. An example use for this 2725 ** interface is to keep a GUI updated during a large query. 2726 ** 2727 ** ^The parameter P is passed through as the only parameter to the 2728 ** callback function X. ^The parameter N is the approximate number of 2729 ** [virtual machine instructions] that are evaluated between successive 2730 ** invocations of the callback X. ^If N is less than one then the progress 2731 ** handler is disabled. 2732 ** 2733 ** ^Only a single progress handler may be defined at one time per 2734 ** [database connection]; setting a new progress handler cancels the 2735 ** old one. ^Setting parameter X to NULL disables the progress handler. 2736 ** ^The progress handler is also disabled by setting N to a value less 2737 ** than 1. 2738 ** 2739 ** ^If the progress callback returns non-zero, the operation is 2740 ** interrupted. This feature can be used to implement a 2741 ** "Cancel" button on a GUI progress dialog box. 2742 ** 2743 ** The progress handler callback must not do anything that will modify 2744 ** the database connection that invoked the progress handler. 2745 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 2746 ** database connections for the meaning of "modify" in this paragraph. 2747 ** 2748 */ 2749 SQLITE_API void SQLITE_STDCALL sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); 2750 2751 /* 2752 ** CAPI3REF: Opening A New Database Connection 2753 ** CONSTRUCTOR: sqlite3 2754 ** 2755 ** ^These routines open an SQLite database file as specified by the 2756 ** filename argument. ^The filename argument is interpreted as UTF-8 for 2757 ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte 2758 ** order for sqlite3_open16(). ^(A [database connection] handle is usually 2759 ** returned in *ppDb, even if an error occurs. The only exception is that 2760 ** if SQLite is unable to allocate memory to hold the [sqlite3] object, 2761 ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] 2762 ** object.)^ ^(If the database is opened (and/or created) successfully, then 2763 ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The 2764 ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain 2765 ** an English language description of the error following a failure of any 2766 ** of the sqlite3_open() routines. 2767 ** 2768 ** ^The default encoding will be UTF-8 for databases created using 2769 ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases 2770 ** created using sqlite3_open16() will be UTF-16 in the native byte order. 2771 ** 2772 ** Whether or not an error occurs when it is opened, resources 2773 ** associated with the [database connection] handle should be released by 2774 ** passing it to [sqlite3_close()] when it is no longer required. 2775 ** 2776 ** The sqlite3_open_v2() interface works like sqlite3_open() 2777 ** except that it accepts two additional parameters for additional control 2778 ** over the new database connection. ^(The flags parameter to 2779 ** sqlite3_open_v2() can take one of 2780 ** the following three values, optionally combined with the 2781 ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE], 2782 ** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^ 2783 ** 2784 ** <dl> 2785 ** ^(<dt>[SQLITE_OPEN_READONLY]</dt> 2786 ** <dd>The database is opened in read-only mode. If the database does not 2787 ** already exist, an error is returned.</dd>)^ 2788 ** 2789 ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> 2790 ** <dd>The database is opened for reading and writing if possible, or reading 2791 ** only if the file is write protected by the operating system. In either 2792 ** case the database must already exist, otherwise an error is returned.</dd>)^ 2793 ** 2794 ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> 2795 ** <dd>The database is opened for reading and writing, and is created if 2796 ** it does not already exist. This is the behavior that is always used for 2797 ** sqlite3_open() and sqlite3_open16().</dd>)^ 2798 ** </dl> 2799 ** 2800 ** If the 3rd parameter to sqlite3_open_v2() is not one of the 2801 ** combinations shown above optionally combined with other 2802 ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] 2803 ** then the behavior is undefined. 2804 ** 2805 ** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection 2806 ** opens in the multi-thread [threading mode] as long as the single-thread 2807 ** mode has not been set at compile-time or start-time. ^If the 2808 ** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens 2809 ** in the serialized [threading mode] unless single-thread was 2810 ** previously selected at compile-time or start-time. 2811 ** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be 2812 ** eligible to use [shared cache mode], regardless of whether or not shared 2813 ** cache is enabled using [sqlite3_enable_shared_cache()]. ^The 2814 ** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not 2815 ** participate in [shared cache mode] even if it is enabled. 2816 ** 2817 ** ^The fourth parameter to sqlite3_open_v2() is the name of the 2818 ** [sqlite3_vfs] object that defines the operating system interface that 2819 ** the new database connection should use. ^If the fourth parameter is 2820 ** a NULL pointer then the default [sqlite3_vfs] object is used. 2821 ** 2822 ** ^If the filename is ":memory:", then a private, temporary in-memory database 2823 ** is created for the connection. ^This in-memory database will vanish when 2824 ** the database connection is closed. Future versions of SQLite might 2825 ** make use of additional special filenames that begin with the ":" character. 2826 ** It is recommended that when a database filename actually does begin with 2827 ** a ":" character you should prefix the filename with a pathname such as 2828 ** "./" to avoid ambiguity. 2829 ** 2830 ** ^If the filename is an empty string, then a private, temporary 2831 ** on-disk database will be created. ^This private database will be 2832 ** automatically deleted as soon as the database connection is closed. 2833 ** 2834 ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> 2835 ** 2836 ** ^If [URI filename] interpretation is enabled, and the filename argument 2837 ** begins with "file:", then the filename is interpreted as a URI. ^URI 2838 ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is 2839 ** set in the fourth argument to sqlite3_open_v2(), or if it has 2840 ** been enabled globally using the [SQLITE_CONFIG_URI] option with the 2841 ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. 2842 ** As of SQLite version 3.7.7, URI filename interpretation is turned off 2843 ** by default, but future releases of SQLite might enable URI filename 2844 ** interpretation by default. See "[URI filenames]" for additional 2845 ** information. 2846 ** 2847 ** URI filenames are parsed according to RFC 3986. ^If the URI contains an 2848 ** authority, then it must be either an empty string or the string 2849 ** "localhost". ^If the authority is not an empty string or "localhost", an 2850 ** error is returned to the caller. ^The fragment component of a URI, if 2851 ** present, is ignored. 2852 ** 2853 ** ^SQLite uses the path component of the URI as the name of the disk file 2854 ** which contains the database. ^If the path begins with a '/' character, 2855 ** then it is interpreted as an absolute path. ^If the path does not begin 2856 ** with a '/' (meaning that the authority section is omitted from the URI) 2857 ** then the path is interpreted as a relative path. 2858 ** ^(On windows, the first component of an absolute path 2859 ** is a drive specification (e.g. "C:").)^ 2860 ** 2861 ** [[core URI query parameters]] 2862 ** The query component of a URI may contain parameters that are interpreted 2863 ** either by SQLite itself, or by a [VFS | custom VFS implementation]. 2864 ** SQLite and its built-in [VFSes] interpret the 2865 ** following query parameters: 2866 ** 2867 ** <ul> 2868 ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of 2869 ** a VFS object that provides the operating system interface that should 2870 ** be used to access the database file on disk. ^If this option is set to 2871 ** an empty string the default VFS object is used. ^Specifying an unknown 2872 ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is 2873 ** present, then the VFS specified by the option takes precedence over 2874 ** the value passed as the fourth parameter to sqlite3_open_v2(). 2875 ** 2876 ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", 2877 ** "rwc", or "memory". Attempting to set it to any other value is 2878 ** an error)^. 2879 ** ^If "ro" is specified, then the database is opened for read-only 2880 ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 2881 ** third argument to sqlite3_open_v2(). ^If the mode option is set to 2882 ** "rw", then the database is opened for read-write (but not create) 2883 ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 2884 ** been set. ^Value "rwc" is equivalent to setting both 2885 ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is 2886 ** set to "memory" then a pure [in-memory database] that never reads 2887 ** or writes from disk is used. ^It is an error to specify a value for 2888 ** the mode parameter that is less restrictive than that specified by 2889 ** the flags passed in the third parameter to sqlite3_open_v2(). 2890 ** 2891 ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or 2892 ** "private". ^Setting it to "shared" is equivalent to setting the 2893 ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to 2894 ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is 2895 ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. 2896 ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in 2897 ** a URI filename, its value overrides any behavior requested by setting 2898 ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. 2899 ** 2900 ** <li> <b>psow</b>: ^The psow parameter indicates whether or not the 2901 ** [powersafe overwrite] property does or does not apply to the 2902 ** storage media on which the database file resides. 2903 ** 2904 ** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter 2905 ** which if set disables file locking in rollback journal modes. This 2906 ** is useful for accessing a database on a filesystem that does not 2907 ** support locking. Caution: Database corruption might result if two 2908 ** or more processes write to the same database and any one of those 2909 ** processes uses nolock=1. 2910 ** 2911 ** <li> <b>immutable</b>: ^The immutable parameter is a boolean query 2912 ** parameter that indicates that the database file is stored on 2913 ** read-only media. ^When immutable is set, SQLite assumes that the 2914 ** database file cannot be changed, even by a process with higher 2915 ** privilege, and so the database is opened read-only and all locking 2916 ** and change detection is disabled. Caution: Setting the immutable 2917 ** property on a database file that does in fact change can result 2918 ** in incorrect query results and/or [SQLITE_CORRUPT] errors. 2919 ** See also: [SQLITE_IOCAP_IMMUTABLE]. 2920 ** 2921 ** </ul> 2922 ** 2923 ** ^Specifying an unknown parameter in the query component of a URI is not an 2924 ** error. Future versions of SQLite might understand additional query 2925 ** parameters. See "[query parameters with special meaning to SQLite]" for 2926 ** additional information. 2927 ** 2928 ** [[URI filename examples]] <h3>URI filename examples</h3> 2929 ** 2930 ** <table border="1" align=center cellpadding=5> 2931 ** <tr><th> URI filenames <th> Results 2932 ** <tr><td> file:data.db <td> 2933 ** Open the file "data.db" in the current directory. 2934 ** <tr><td> file:/home/fred/data.db<br> 2935 ** file:///home/fred/data.db <br> 2936 ** file://localhost/home/fred/data.db <br> <td> 2937 ** Open the database file "/home/fred/data.db". 2938 ** <tr><td> file://darkstar/home/fred/data.db <td> 2939 ** An error. "darkstar" is not a recognized authority. 2940 ** <tr><td style="white-space:nowrap"> 2941 ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db 2942 ** <td> Windows only: Open the file "data.db" on fred's desktop on drive 2943 ** C:. Note that the %20 escaping in this example is not strictly 2944 ** necessary - space characters can be used literally 2945 ** in URI filenames. 2946 ** <tr><td> file:data.db?mode=ro&cache=private <td> 2947 ** Open file "data.db" in the current directory for read-only access. 2948 ** Regardless of whether or not shared-cache mode is enabled by 2949 ** default, use a private cache. 2950 ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> 2951 ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" 2952 ** that uses dot-files in place of posix advisory locking. 2953 ** <tr><td> file:data.db?mode=readonly <td> 2954 ** An error. "readonly" is not a valid option for the "mode" parameter. 2955 ** </table> 2956 ** 2957 ** ^URI hexadecimal escape sequences (%HH) are supported within the path and 2958 ** query components of a URI. A hexadecimal escape sequence consists of a 2959 ** percent sign - "%" - followed by exactly two hexadecimal digits 2960 ** specifying an octet value. ^Before the path or query components of a 2961 ** URI filename are interpreted, they are encoded using UTF-8 and all 2962 ** hexadecimal escape sequences replaced by a single byte containing the 2963 ** corresponding octet. If this process generates an invalid UTF-8 encoding, 2964 ** the results are undefined. 2965 ** 2966 ** <b>Note to Windows users:</b> The encoding used for the filename argument 2967 ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever 2968 ** codepage is currently defined. Filenames containing international 2969 ** characters must be converted to UTF-8 prior to passing them into 2970 ** sqlite3_open() or sqlite3_open_v2(). 2971 ** 2972 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set 2973 ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various 2974 ** features that require the use of temporary files may fail. 2975 ** 2976 ** See also: [sqlite3_temp_directory] 2977 */ 2978 SQLITE_API int SQLITE_STDCALL sqlite3_open( 2979 const char *filename, /* Database filename (UTF-8) */ 2980 sqlite3 **ppDb /* OUT: SQLite db handle */ 2981 ); 2982 SQLITE_API int SQLITE_STDCALL sqlite3_open16( 2983 const void *filename, /* Database filename (UTF-16) */ 2984 sqlite3 **ppDb /* OUT: SQLite db handle */ 2985 ); 2986 SQLITE_API int SQLITE_STDCALL sqlite3_open_v2( 2987 const char *filename, /* Database filename (UTF-8) */ 2988 sqlite3 **ppDb, /* OUT: SQLite db handle */ 2989 int flags, /* Flags */ 2990 const char *zVfs /* Name of VFS module to use */ 2991 ); 2992 2993 /* 2994 ** CAPI3REF: Obtain Values For URI Parameters 2995 ** 2996 ** These are utility routines, useful to VFS implementations, that check 2997 ** to see if a database file was a URI that contained a specific query 2998 ** parameter, and if so obtains the value of that query parameter. 2999 ** 3000 ** If F is the database filename pointer passed into the xOpen() method of 3001 ** a VFS implementation when the flags parameter to xOpen() has one or 3002 ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and 3003 ** P is the name of the query parameter, then 3004 ** sqlite3_uri_parameter(F,P) returns the value of the P 3005 ** parameter if it exists or a NULL pointer if P does not appear as a 3006 ** query parameter on F. If P is a query parameter of F 3007 ** has no explicit value, then sqlite3_uri_parameter(F,P) returns 3008 ** a pointer to an empty string. 3009 ** 3010 ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean 3011 ** parameter and returns true (1) or false (0) according to the value 3012 ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the 3013 ** value of query parameter P is one of "yes", "true", or "on" in any 3014 ** case or if the value begins with a non-zero number. The 3015 ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of 3016 ** query parameter P is one of "no", "false", or "off" in any case or 3017 ** if the value begins with a numeric zero. If P is not a query 3018 ** parameter on F or if the value of P is does not match any of the 3019 ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). 3020 ** 3021 ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a 3022 ** 64-bit signed integer and returns that integer, or D if P does not 3023 ** exist. If the value of P is something other than an integer, then 3024 ** zero is returned. 3025 ** 3026 ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and 3027 ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and 3028 ** is not a database file pathname pointer that SQLite passed into the xOpen 3029 ** VFS method, then the behavior of this routine is undefined and probably 3030 ** undesirable. 3031 */ 3032 SQLITE_API const char *SQLITE_STDCALL sqlite3_uri_parameter(const char *zFilename, const char *zParam); 3033 SQLITE_API int SQLITE_STDCALL sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault); 3034 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_uri_int64(const char*, const char*, sqlite3_int64); 3035 3036 3037 /* 3038 ** CAPI3REF: Error Codes And Messages 3039 ** METHOD: sqlite3 3040 ** 3041 ** ^If the most recent sqlite3_* API call associated with 3042 ** [database connection] D failed, then the sqlite3_errcode(D) interface 3043 ** returns the numeric [result code] or [extended result code] for that 3044 ** API call. 3045 ** If the most recent API call was successful, 3046 ** then the return value from sqlite3_errcode() is undefined. 3047 ** ^The sqlite3_extended_errcode() 3048 ** interface is the same except that it always returns the 3049 ** [extended result code] even when extended result codes are 3050 ** disabled. 3051 ** 3052 ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language 3053 ** text that describes the error, as either UTF-8 or UTF-16 respectively. 3054 ** ^(Memory to hold the error message string is managed internally. 3055 ** The application does not need to worry about freeing the result. 3056 ** However, the error string might be overwritten or deallocated by 3057 ** subsequent calls to other SQLite interface functions.)^ 3058 ** 3059 ** ^The sqlite3_errstr() interface returns the English-language text 3060 ** that describes the [result code], as UTF-8. 3061 ** ^(Memory to hold the error message string is managed internally 3062 ** and must not be freed by the application)^. 3063 ** 3064 ** When the serialized [threading mode] is in use, it might be the 3065 ** case that a second error occurs on a separate thread in between 3066 ** the time of the first error and the call to these interfaces. 3067 ** When that happens, the second error will be reported since these 3068 ** interfaces always report the most recent result. To avoid 3069 ** this, each thread can obtain exclusive use of the [database connection] D 3070 ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning 3071 ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after 3072 ** all calls to the interfaces listed here are completed. 3073 ** 3074 ** If an interface fails with SQLITE_MISUSE, that means the interface 3075 ** was invoked incorrectly by the application. In that case, the 3076 ** error code and message may or may not be set. 3077 */ 3078 SQLITE_API int SQLITE_STDCALL sqlite3_errcode(sqlite3 *db); 3079 SQLITE_API int SQLITE_STDCALL sqlite3_extended_errcode(sqlite3 *db); 3080 SQLITE_API const char *SQLITE_STDCALL sqlite3_errmsg(sqlite3*); 3081 SQLITE_API const void *SQLITE_STDCALL sqlite3_errmsg16(sqlite3*); 3082 SQLITE_API const char *SQLITE_STDCALL sqlite3_errstr(int); 3083 3084 /* 3085 ** CAPI3REF: Prepared Statement Object 3086 ** KEYWORDS: {prepared statement} {prepared statements} 3087 ** 3088 ** An instance of this object represents a single SQL statement that 3089 ** has been compiled into binary form and is ready to be evaluated. 3090 ** 3091 ** Think of each SQL statement as a separate computer program. The 3092 ** original SQL text is source code. A prepared statement object 3093 ** is the compiled object code. All SQL must be converted into a 3094 ** prepared statement before it can be run. 3095 ** 3096 ** The life-cycle of a prepared statement object usually goes like this: 3097 ** 3098 ** <ol> 3099 ** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. 3100 ** <li> Bind values to [parameters] using the sqlite3_bind_*() 3101 ** interfaces. 3102 ** <li> Run the SQL by calling [sqlite3_step()] one or more times. 3103 ** <li> Reset the prepared statement using [sqlite3_reset()] then go back 3104 ** to step 2. Do this zero or more times. 3105 ** <li> Destroy the object using [sqlite3_finalize()]. 3106 ** </ol> 3107 */ 3108 typedef struct sqlite3_stmt sqlite3_stmt; 3109 3110 /* 3111 ** CAPI3REF: Run-time Limits 3112 ** METHOD: sqlite3 3113 ** 3114 ** ^(This interface allows the size of various constructs to be limited 3115 ** on a connection by connection basis. The first parameter is the 3116 ** [database connection] whose limit is to be set or queried. The 3117 ** second parameter is one of the [limit categories] that define a 3118 ** class of constructs to be size limited. The third parameter is the 3119 ** new limit for that construct.)^ 3120 ** 3121 ** ^If the new limit is a negative number, the limit is unchanged. 3122 ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 3123 ** [limits | hard upper bound] 3124 ** set at compile-time by a C preprocessor macro called 3125 ** [limits | SQLITE_MAX_<i>NAME</i>]. 3126 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^ 3127 ** ^Attempts to increase a limit above its hard upper bound are 3128 ** silently truncated to the hard upper bound. 3129 ** 3130 ** ^Regardless of whether or not the limit was changed, the 3131 ** [sqlite3_limit()] interface returns the prior value of the limit. 3132 ** ^Hence, to find the current value of a limit without changing it, 3133 ** simply invoke this interface with the third parameter set to -1. 3134 ** 3135 ** Run-time limits are intended for use in applications that manage 3136 ** both their own internal database and also databases that are controlled 3137 ** by untrusted external sources. An example application might be a 3138 ** web browser that has its own databases for storing history and 3139 ** separate databases controlled by JavaScript applications downloaded 3140 ** off the Internet. The internal databases can be given the 3141 ** large, default limits. Databases managed by external sources can 3142 ** be given much smaller limits designed to prevent a denial of service 3143 ** attack. Developers might also want to use the [sqlite3_set_authorizer()] 3144 ** interface to further control untrusted SQL. The size of the database 3145 ** created by an untrusted script can be contained using the 3146 ** [max_page_count] [PRAGMA]. 3147 ** 3148 ** New run-time limit categories may be added in future releases. 3149 */ 3150 SQLITE_API int SQLITE_STDCALL sqlite3_limit(sqlite3*, int id, int newVal); 3151 3152 /* 3153 ** CAPI3REF: Run-Time Limit Categories 3154 ** KEYWORDS: {limit category} {*limit categories} 3155 ** 3156 ** These constants define various performance limits 3157 ** that can be lowered at run-time using [sqlite3_limit()]. 3158 ** The synopsis of the meanings of the various limits is shown below. 3159 ** Additional information is available at [limits | Limits in SQLite]. 3160 ** 3161 ** <dl> 3162 ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> 3163 ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ 3164 ** 3165 ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> 3166 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ 3167 ** 3168 ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> 3169 ** <dd>The maximum number of columns in a table definition or in the 3170 ** result set of a [SELECT] or the maximum number of columns in an index 3171 ** or in an ORDER BY or GROUP BY clause.</dd>)^ 3172 ** 3173 ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> 3174 ** <dd>The maximum depth of the parse tree on any expression.</dd>)^ 3175 ** 3176 ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> 3177 ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ 3178 ** 3179 ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> 3180 ** <dd>The maximum number of instructions in a virtual machine program 3181 ** used to implement an SQL statement. This limit is not currently 3182 ** enforced, though that might be added in some future release of 3183 ** SQLite.</dd>)^ 3184 ** 3185 ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> 3186 ** <dd>The maximum number of arguments on a function.</dd>)^ 3187 ** 3188 ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> 3189 ** <dd>The maximum number of [ATTACH | attached databases].)^</dd> 3190 ** 3191 ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] 3192 ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> 3193 ** <dd>The maximum length of the pattern argument to the [LIKE] or 3194 ** [GLOB] operators.</dd>)^ 3195 ** 3196 ** [[SQLITE_LIMIT_VARIABLE_NUMBER]] 3197 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> 3198 ** <dd>The maximum index number of any [parameter] in an SQL statement.)^ 3199 ** 3200 ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> 3201 ** <dd>The maximum depth of recursion for triggers.</dd>)^ 3202 ** 3203 ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> 3204 ** <dd>The maximum number of auxiliary worker threads that a single 3205 ** [prepared statement] may start.</dd>)^ 3206 ** </dl> 3207 */ 3208 #define SQLITE_LIMIT_LENGTH 0 3209 #define SQLITE_LIMIT_SQL_LENGTH 1 3210 #define SQLITE_LIMIT_COLUMN 2 3211 #define SQLITE_LIMIT_EXPR_DEPTH 3 3212 #define SQLITE_LIMIT_COMPOUND_SELECT 4 3213 #define SQLITE_LIMIT_VDBE_OP 5 3214 #define SQLITE_LIMIT_FUNCTION_ARG 6 3215 #define SQLITE_LIMIT_ATTACHED 7 3216 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 3217 #define SQLITE_LIMIT_VARIABLE_NUMBER 9 3218 #define SQLITE_LIMIT_TRIGGER_DEPTH 10 3219 #define SQLITE_LIMIT_WORKER_THREADS 11 3220 3221 /* 3222 ** CAPI3REF: Compiling An SQL Statement 3223 ** KEYWORDS: {SQL statement compiler} 3224 ** METHOD: sqlite3 3225 ** CONSTRUCTOR: sqlite3_stmt 3226 ** 3227 ** To execute an SQL query, it must first be compiled into a byte-code 3228 ** program using one of these routines. 3229 ** 3230 ** The first argument, "db", is a [database connection] obtained from a 3231 ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or 3232 ** [sqlite3_open16()]. The database connection must not have been closed. 3233 ** 3234 ** The second argument, "zSql", is the statement to be compiled, encoded 3235 ** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2() 3236 ** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2() 3237 ** use UTF-16. 3238 ** 3239 ** ^If the nByte argument is negative, then zSql is read up to the 3240 ** first zero terminator. ^If nByte is positive, then it is the 3241 ** number of bytes read from zSql. ^If nByte is zero, then no prepared 3242 ** statement is generated. 3243 ** If the caller knows that the supplied string is nul-terminated, then 3244 ** there is a small performance advantage to passing an nByte parameter that 3245 ** is the number of bytes in the input string <i>including</i> 3246 ** the nul-terminator. 3247 ** 3248 ** ^If pzTail is not NULL then *pzTail is made to point to the first byte 3249 ** past the end of the first SQL statement in zSql. These routines only 3250 ** compile the first statement in zSql, so *pzTail is left pointing to 3251 ** what remains uncompiled. 3252 ** 3253 ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be 3254 ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set 3255 ** to NULL. ^If the input text contains no SQL (if the input is an empty 3256 ** string or a comment) then *ppStmt is set to NULL. 3257 ** The calling procedure is responsible for deleting the compiled 3258 ** SQL statement using [sqlite3_finalize()] after it has finished with it. 3259 ** ppStmt may not be NULL. 3260 ** 3261 ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; 3262 ** otherwise an [error code] is returned. 3263 ** 3264 ** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are 3265 ** recommended for all new programs. The two older interfaces are retained 3266 ** for backwards compatibility, but their use is discouraged. 3267 ** ^In the "v2" interfaces, the prepared statement 3268 ** that is returned (the [sqlite3_stmt] object) contains a copy of the 3269 ** original SQL text. This causes the [sqlite3_step()] interface to 3270 ** behave differently in three ways: 3271 ** 3272 ** <ol> 3273 ** <li> 3274 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it 3275 ** always used to do, [sqlite3_step()] will automatically recompile the SQL 3276 ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] 3277 ** retries will occur before sqlite3_step() gives up and returns an error. 3278 ** </li> 3279 ** 3280 ** <li> 3281 ** ^When an error occurs, [sqlite3_step()] will return one of the detailed 3282 ** [error codes] or [extended error codes]. ^The legacy behavior was that 3283 ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code 3284 ** and the application would have to make a second call to [sqlite3_reset()] 3285 ** in order to find the underlying cause of the problem. With the "v2" prepare 3286 ** interfaces, the underlying reason for the error is returned immediately. 3287 ** </li> 3288 ** 3289 ** <li> 3290 ** ^If the specific value bound to [parameter | host parameter] in the 3291 ** WHERE clause might influence the choice of query plan for a statement, 3292 ** then the statement will be automatically recompiled, as if there had been 3293 ** a schema change, on the first [sqlite3_step()] call following any change 3294 ** to the [sqlite3_bind_text | bindings] of that [parameter]. 3295 ** ^The specific value of WHERE-clause [parameter] might influence the 3296 ** choice of query plan if the parameter is the left-hand side of a [LIKE] 3297 ** or [GLOB] operator or if the parameter is compared to an indexed column 3298 ** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled. 3299 ** </li> 3300 ** </ol> 3301 */ 3302 SQLITE_API int SQLITE_STDCALL sqlite3_prepare( 3303 sqlite3 *db, /* Database handle */ 3304 const char *zSql, /* SQL statement, UTF-8 encoded */ 3305 int nByte, /* Maximum length of zSql in bytes. */ 3306 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3307 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 3308 ); 3309 SQLITE_API int SQLITE_STDCALL sqlite3_prepare_v2( 3310 sqlite3 *db, /* Database handle */ 3311 const char *zSql, /* SQL statement, UTF-8 encoded */ 3312 int nByte, /* Maximum length of zSql in bytes. */ 3313 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3314 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 3315 ); 3316 SQLITE_API int SQLITE_STDCALL sqlite3_prepare16( 3317 sqlite3 *db, /* Database handle */ 3318 const void *zSql, /* SQL statement, UTF-16 encoded */ 3319 int nByte, /* Maximum length of zSql in bytes. */ 3320 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3321 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 3322 ); 3323 SQLITE_API int SQLITE_STDCALL sqlite3_prepare16_v2( 3324 sqlite3 *db, /* Database handle */ 3325 const void *zSql, /* SQL statement, UTF-16 encoded */ 3326 int nByte, /* Maximum length of zSql in bytes. */ 3327 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 3328 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 3329 ); 3330 3331 /* 3332 ** CAPI3REF: Retrieving Statement SQL 3333 ** METHOD: sqlite3_stmt 3334 ** 3335 ** ^This interface can be used to retrieve a saved copy of the original 3336 ** SQL text used to create a [prepared statement] if that statement was 3337 ** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()]. 3338 */ 3339 SQLITE_API const char *SQLITE_STDCALL sqlite3_sql(sqlite3_stmt *pStmt); 3340 3341 /* 3342 ** CAPI3REF: Determine If An SQL Statement Writes The Database 3343 ** METHOD: sqlite3_stmt 3344 ** 3345 ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if 3346 ** and only if the [prepared statement] X makes no direct changes to 3347 ** the content of the database file. 3348 ** 3349 ** Note that [application-defined SQL functions] or 3350 ** [virtual tables] might change the database indirectly as a side effect. 3351 ** ^(For example, if an application defines a function "eval()" that 3352 ** calls [sqlite3_exec()], then the following SQL statement would 3353 ** change the database file through side-effects: 3354 ** 3355 ** <blockquote><pre> 3356 ** SELECT eval('DELETE FROM t1') FROM t2; 3357 ** </pre></blockquote> 3358 ** 3359 ** But because the [SELECT] statement does not change the database file 3360 ** directly, sqlite3_stmt_readonly() would still return true.)^ 3361 ** 3362 ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], 3363 ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, 3364 ** since the statements themselves do not actually modify the database but 3365 ** rather they control the timing of when other statements modify the 3366 ** database. ^The [ATTACH] and [DETACH] statements also cause 3367 ** sqlite3_stmt_readonly() to return true since, while those statements 3368 ** change the configuration of a database connection, they do not make 3369 ** changes to the content of the database files on disk. 3370 */ 3371 SQLITE_API int SQLITE_STDCALL sqlite3_stmt_readonly(sqlite3_stmt *pStmt); 3372 3373 /* 3374 ** CAPI3REF: Determine If A Prepared Statement Has Been Reset 3375 ** METHOD: sqlite3_stmt 3376 ** 3377 ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the 3378 ** [prepared statement] S has been stepped at least once using 3379 ** [sqlite3_step(S)] but has neither run to completion (returned 3380 ** [SQLITE_DONE] from [sqlite3_step(S)]) nor 3381 ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) 3382 ** interface returns false if S is a NULL pointer. If S is not a 3383 ** NULL pointer and is not a pointer to a valid [prepared statement] 3384 ** object, then the behavior is undefined and probably undesirable. 3385 ** 3386 ** This interface can be used in combination [sqlite3_next_stmt()] 3387 ** to locate all prepared statements associated with a database 3388 ** connection that are in need of being reset. This can be used, 3389 ** for example, in diagnostic routines to search for prepared 3390 ** statements that are holding a transaction open. 3391 */ 3392 SQLITE_API int SQLITE_STDCALL sqlite3_stmt_busy(sqlite3_stmt*); 3393 3394 /* 3395 ** CAPI3REF: Dynamically Typed Value Object 3396 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} 3397 ** 3398 ** SQLite uses the sqlite3_value object to represent all values 3399 ** that can be stored in a database table. SQLite uses dynamic typing 3400 ** for the values it stores. ^Values stored in sqlite3_value objects 3401 ** can be integers, floating point values, strings, BLOBs, or NULL. 3402 ** 3403 ** An sqlite3_value object may be either "protected" or "unprotected". 3404 ** Some interfaces require a protected sqlite3_value. Other interfaces 3405 ** will accept either a protected or an unprotected sqlite3_value. 3406 ** Every interface that accepts sqlite3_value arguments specifies 3407 ** whether or not it requires a protected sqlite3_value. The 3408 ** [sqlite3_value_dup()] interface can be used to construct a new 3409 ** protected sqlite3_value from an unprotected sqlite3_value. 3410 ** 3411 ** The terms "protected" and "unprotected" refer to whether or not 3412 ** a mutex is held. An internal mutex is held for a protected 3413 ** sqlite3_value object but no mutex is held for an unprotected 3414 ** sqlite3_value object. If SQLite is compiled to be single-threaded 3415 ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) 3416 ** or if SQLite is run in one of reduced mutex modes 3417 ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] 3418 ** then there is no distinction between protected and unprotected 3419 ** sqlite3_value objects and they can be used interchangeably. However, 3420 ** for maximum code portability it is recommended that applications 3421 ** still make the distinction between protected and unprotected 3422 ** sqlite3_value objects even when not strictly required. 3423 ** 3424 ** ^The sqlite3_value objects that are passed as parameters into the 3425 ** implementation of [application-defined SQL functions] are protected. 3426 ** ^The sqlite3_value object returned by 3427 ** [sqlite3_column_value()] is unprotected. 3428 ** Unprotected sqlite3_value objects may only be used with 3429 ** [sqlite3_result_value()] and [sqlite3_bind_value()]. 3430 ** The [sqlite3_value_blob | sqlite3_value_type()] family of 3431 ** interfaces require protected sqlite3_value objects. 3432 */ 3433 typedef struct Mem sqlite3_value; 3434 3435 /* 3436 ** CAPI3REF: SQL Function Context Object 3437 ** 3438 ** The context in which an SQL function executes is stored in an 3439 ** sqlite3_context object. ^A pointer to an sqlite3_context object 3440 ** is always first parameter to [application-defined SQL functions]. 3441 ** The application-defined SQL function implementation will pass this 3442 ** pointer through into calls to [sqlite3_result_int | sqlite3_result()], 3443 ** [sqlite3_aggregate_context()], [sqlite3_user_data()], 3444 ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], 3445 ** and/or [sqlite3_set_auxdata()]. 3446 */ 3447 typedef struct sqlite3_context sqlite3_context; 3448 3449 /* 3450 ** CAPI3REF: Binding Values To Prepared Statements 3451 ** KEYWORDS: {host parameter} {host parameters} {host parameter name} 3452 ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} 3453 ** METHOD: sqlite3_stmt 3454 ** 3455 ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, 3456 ** literals may be replaced by a [parameter] that matches one of following 3457 ** templates: 3458 ** 3459 ** <ul> 3460 ** <li> ? 3461 ** <li> ?NNN 3462 ** <li> :VVV 3463 ** <li> @VVV 3464 ** <li> $VVV 3465 ** </ul> 3466 ** 3467 ** In the templates above, NNN represents an integer literal, 3468 ** and VVV represents an alphanumeric identifier.)^ ^The values of these 3469 ** parameters (also called "host parameter names" or "SQL parameters") 3470 ** can be set using the sqlite3_bind_*() routines defined here. 3471 ** 3472 ** ^The first argument to the sqlite3_bind_*() routines is always 3473 ** a pointer to the [sqlite3_stmt] object returned from 3474 ** [sqlite3_prepare_v2()] or its variants. 3475 ** 3476 ** ^The second argument is the index of the SQL parameter to be set. 3477 ** ^The leftmost SQL parameter has an index of 1. ^When the same named 3478 ** SQL parameter is used more than once, second and subsequent 3479 ** occurrences have the same index as the first occurrence. 3480 ** ^The index for named parameters can be looked up using the 3481 ** [sqlite3_bind_parameter_index()] API if desired. ^The index 3482 ** for "?NNN" parameters is the value of NNN. 3483 ** ^The NNN value must be between 1 and the [sqlite3_limit()] 3484 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999). 3485 ** 3486 ** ^The third argument is the value to bind to the parameter. 3487 ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() 3488 ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter 3489 ** is ignored and the end result is the same as sqlite3_bind_null(). 3490 ** 3491 ** ^(In those routines that have a fourth argument, its value is the 3492 ** number of bytes in the parameter. To be clear: the value is the 3493 ** number of <u>bytes</u> in the value, not the number of characters.)^ 3494 ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() 3495 ** is negative, then the length of the string is 3496 ** the number of bytes up to the first zero terminator. 3497 ** If the fourth parameter to sqlite3_bind_blob() is negative, then 3498 ** the behavior is undefined. 3499 ** If a non-negative fourth parameter is provided to sqlite3_bind_text() 3500 ** or sqlite3_bind_text16() or sqlite3_bind_text64() then 3501 ** that parameter must be the byte offset 3502 ** where the NUL terminator would occur assuming the string were NUL 3503 ** terminated. If any NUL characters occur at byte offsets less than 3504 ** the value of the fourth parameter then the resulting string value will 3505 ** contain embedded NULs. The result of expressions involving strings 3506 ** with embedded NULs is undefined. 3507 ** 3508 ** ^The fifth argument to the BLOB and string binding interfaces 3509 ** is a destructor used to dispose of the BLOB or 3510 ** string after SQLite has finished with it. ^The destructor is called 3511 ** to dispose of the BLOB or string even if the call to bind API fails. 3512 ** ^If the fifth argument is 3513 ** the special value [SQLITE_STATIC], then SQLite assumes that the 3514 ** information is in static, unmanaged space and does not need to be freed. 3515 ** ^If the fifth argument has the value [SQLITE_TRANSIENT], then 3516 ** SQLite makes its own private copy of the data immediately, before 3517 ** the sqlite3_bind_*() routine returns. 3518 ** 3519 ** ^The sixth argument to sqlite3_bind_text64() must be one of 3520 ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] 3521 ** to specify the encoding of the text in the third parameter. If 3522 ** the sixth argument to sqlite3_bind_text64() is not one of the 3523 ** allowed values shown above, or if the text encoding is different 3524 ** from the encoding specified by the sixth parameter, then the behavior 3525 ** is undefined. 3526 ** 3527 ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that 3528 ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory 3529 ** (just an integer to hold its size) while it is being processed. 3530 ** Zeroblobs are intended to serve as placeholders for BLOBs whose 3531 ** content is later written using 3532 ** [sqlite3_blob_open | incremental BLOB I/O] routines. 3533 ** ^A negative value for the zeroblob results in a zero-length BLOB. 3534 ** 3535 ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer 3536 ** for the [prepared statement] or with a prepared statement for which 3537 ** [sqlite3_step()] has been called more recently than [sqlite3_reset()], 3538 ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() 3539 ** routine is passed a [prepared statement] that has been finalized, the 3540 ** result is undefined and probably harmful. 3541 ** 3542 ** ^Bindings are not cleared by the [sqlite3_reset()] routine. 3543 ** ^Unbound parameters are interpreted as NULL. 3544 ** 3545 ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an 3546 ** [error code] if anything goes wrong. 3547 ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB 3548 ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or 3549 ** [SQLITE_MAX_LENGTH]. 3550 ** ^[SQLITE_RANGE] is returned if the parameter 3551 ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. 3552 ** 3553 ** See also: [sqlite3_bind_parameter_count()], 3554 ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. 3555 */ 3556 SQLITE_API int SQLITE_STDCALL sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); 3557 SQLITE_API int SQLITE_STDCALL sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, 3558 void(*)(void*)); 3559 SQLITE_API int SQLITE_STDCALL sqlite3_bind_double(sqlite3_stmt*, int, double); 3560 SQLITE_API int SQLITE_STDCALL sqlite3_bind_int(sqlite3_stmt*, int, int); 3561 SQLITE_API int SQLITE_STDCALL sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); 3562 SQLITE_API int SQLITE_STDCALL sqlite3_bind_null(sqlite3_stmt*, int); 3563 SQLITE_API int SQLITE_STDCALL sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); 3564 SQLITE_API int SQLITE_STDCALL sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); 3565 SQLITE_API int SQLITE_STDCALL sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, 3566 void(*)(void*), unsigned char encoding); 3567 SQLITE_API int SQLITE_STDCALL sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); 3568 SQLITE_API int SQLITE_STDCALL sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); 3569 SQLITE_API int SQLITE_STDCALL sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); 3570 3571 /* 3572 ** CAPI3REF: Number Of SQL Parameters 3573 ** METHOD: sqlite3_stmt 3574 ** 3575 ** ^This routine can be used to find the number of [SQL parameters] 3576 ** in a [prepared statement]. SQL parameters are tokens of the 3577 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as 3578 ** placeholders for values that are [sqlite3_bind_blob | bound] 3579 ** to the parameters at a later time. 3580 ** 3581 ** ^(This routine actually returns the index of the largest (rightmost) 3582 ** parameter. For all forms except ?NNN, this will correspond to the 3583 ** number of unique parameters. If parameters of the ?NNN form are used, 3584 ** there may be gaps in the list.)^ 3585 ** 3586 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 3587 ** [sqlite3_bind_parameter_name()], and 3588 ** [sqlite3_bind_parameter_index()]. 3589 */ 3590 SQLITE_API int SQLITE_STDCALL sqlite3_bind_parameter_count(sqlite3_stmt*); 3591 3592 /* 3593 ** CAPI3REF: Name Of A Host Parameter 3594 ** METHOD: sqlite3_stmt 3595 ** 3596 ** ^The sqlite3_bind_parameter_name(P,N) interface returns 3597 ** the name of the N-th [SQL parameter] in the [prepared statement] P. 3598 ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" 3599 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" 3600 ** respectively. 3601 ** In other words, the initial ":" or "$" or "@" or "?" 3602 ** is included as part of the name.)^ 3603 ** ^Parameters of the form "?" without a following integer have no name 3604 ** and are referred to as "nameless" or "anonymous parameters". 3605 ** 3606 ** ^The first host parameter has an index of 1, not 0. 3607 ** 3608 ** ^If the value N is out of range or if the N-th parameter is 3609 ** nameless, then NULL is returned. ^The returned string is 3610 ** always in UTF-8 encoding even if the named parameter was 3611 ** originally specified as UTF-16 in [sqlite3_prepare16()] or 3612 ** [sqlite3_prepare16_v2()]. 3613 ** 3614 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 3615 ** [sqlite3_bind_parameter_count()], and 3616 ** [sqlite3_bind_parameter_index()]. 3617 */ 3618 SQLITE_API const char *SQLITE_STDCALL sqlite3_bind_parameter_name(sqlite3_stmt*, int); 3619 3620 /* 3621 ** CAPI3REF: Index Of A Parameter With A Given Name 3622 ** METHOD: sqlite3_stmt 3623 ** 3624 ** ^Return the index of an SQL parameter given its name. ^The 3625 ** index value returned is suitable for use as the second 3626 ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero 3627 ** is returned if no matching parameter is found. ^The parameter 3628 ** name must be given in UTF-8 even if the original statement 3629 ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()]. 3630 ** 3631 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 3632 ** [sqlite3_bind_parameter_count()], and 3633 ** [sqlite3_bind_parameter_name()]. 3634 */ 3635 SQLITE_API int SQLITE_STDCALL sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); 3636 3637 /* 3638 ** CAPI3REF: Reset All Bindings On A Prepared Statement 3639 ** METHOD: sqlite3_stmt 3640 ** 3641 ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset 3642 ** the [sqlite3_bind_blob | bindings] on a [prepared statement]. 3643 ** ^Use this routine to reset all host parameters to NULL. 3644 */ 3645 SQLITE_API int SQLITE_STDCALL sqlite3_clear_bindings(sqlite3_stmt*); 3646 3647 /* 3648 ** CAPI3REF: Number Of Columns In A Result Set 3649 ** METHOD: sqlite3_stmt 3650 ** 3651 ** ^Return the number of columns in the result set returned by the 3652 ** [prepared statement]. ^This routine returns 0 if pStmt is an SQL 3653 ** statement that does not return data (for example an [UPDATE]). 3654 ** 3655 ** See also: [sqlite3_data_count()] 3656 */ 3657 SQLITE_API int SQLITE_STDCALL sqlite3_column_count(sqlite3_stmt *pStmt); 3658 3659 /* 3660 ** CAPI3REF: Column Names In A Result Set 3661 ** METHOD: sqlite3_stmt 3662 ** 3663 ** ^These routines return the name assigned to a particular column 3664 ** in the result set of a [SELECT] statement. ^The sqlite3_column_name() 3665 ** interface returns a pointer to a zero-terminated UTF-8 string 3666 ** and sqlite3_column_name16() returns a pointer to a zero-terminated 3667 ** UTF-16 string. ^The first parameter is the [prepared statement] 3668 ** that implements the [SELECT] statement. ^The second parameter is the 3669 ** column number. ^The leftmost column is number 0. 3670 ** 3671 ** ^The returned string pointer is valid until either the [prepared statement] 3672 ** is destroyed by [sqlite3_finalize()] or until the statement is automatically 3673 ** reprepared by the first call to [sqlite3_step()] for a particular run 3674 ** or until the next call to 3675 ** sqlite3_column_name() or sqlite3_column_name16() on the same column. 3676 ** 3677 ** ^If sqlite3_malloc() fails during the processing of either routine 3678 ** (for example during a conversion from UTF-8 to UTF-16) then a 3679 ** NULL pointer is returned. 3680 ** 3681 ** ^The name of a result column is the value of the "AS" clause for 3682 ** that column, if there is an AS clause. If there is no AS clause 3683 ** then the name of the column is unspecified and may change from 3684 ** one release of SQLite to the next. 3685 */ 3686 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_name(sqlite3_stmt*, int N); 3687 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_name16(sqlite3_stmt*, int N); 3688 3689 /* 3690 ** CAPI3REF: Source Of Data In A Query Result 3691 ** METHOD: sqlite3_stmt 3692 ** 3693 ** ^These routines provide a means to determine the database, table, and 3694 ** table column that is the origin of a particular result column in 3695 ** [SELECT] statement. 3696 ** ^The name of the database or table or column can be returned as 3697 ** either a UTF-8 or UTF-16 string. ^The _database_ routines return 3698 ** the database name, the _table_ routines return the table name, and 3699 ** the origin_ routines return the column name. 3700 ** ^The returned string is valid until the [prepared statement] is destroyed 3701 ** using [sqlite3_finalize()] or until the statement is automatically 3702 ** reprepared by the first call to [sqlite3_step()] for a particular run 3703 ** or until the same information is requested 3704 ** again in a different encoding. 3705 ** 3706 ** ^The names returned are the original un-aliased names of the 3707 ** database, table, and column. 3708 ** 3709 ** ^The first argument to these interfaces is a [prepared statement]. 3710 ** ^These functions return information about the Nth result column returned by 3711 ** the statement, where N is the second function argument. 3712 ** ^The left-most column is column 0 for these routines. 3713 ** 3714 ** ^If the Nth column returned by the statement is an expression or 3715 ** subquery and is not a column value, then all of these functions return 3716 ** NULL. ^These routine might also return NULL if a memory allocation error 3717 ** occurs. ^Otherwise, they return the name of the attached database, table, 3718 ** or column that query result column was extracted from. 3719 ** 3720 ** ^As with all other SQLite APIs, those whose names end with "16" return 3721 ** UTF-16 encoded strings and the other functions return UTF-8. 3722 ** 3723 ** ^These APIs are only available if the library was compiled with the 3724 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. 3725 ** 3726 ** If two or more threads call one or more of these routines against the same 3727 ** prepared statement and column at the same time then the results are 3728 ** undefined. 3729 ** 3730 ** If two or more threads call one or more 3731 ** [sqlite3_column_database_name | column metadata interfaces] 3732 ** for the same [prepared statement] and result column 3733 ** at the same time then the results are undefined. 3734 */ 3735 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_database_name(sqlite3_stmt*,int); 3736 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_database_name16(sqlite3_stmt*,int); 3737 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_table_name(sqlite3_stmt*,int); 3738 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_table_name16(sqlite3_stmt*,int); 3739 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_origin_name(sqlite3_stmt*,int); 3740 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_origin_name16(sqlite3_stmt*,int); 3741 3742 /* 3743 ** CAPI3REF: Declared Datatype Of A Query Result 3744 ** METHOD: sqlite3_stmt 3745 ** 3746 ** ^(The first parameter is a [prepared statement]. 3747 ** If this statement is a [SELECT] statement and the Nth column of the 3748 ** returned result set of that [SELECT] is a table column (not an 3749 ** expression or subquery) then the declared type of the table 3750 ** column is returned.)^ ^If the Nth column of the result set is an 3751 ** expression or subquery, then a NULL pointer is returned. 3752 ** ^The returned string is always UTF-8 encoded. 3753 ** 3754 ** ^(For example, given the database schema: 3755 ** 3756 ** CREATE TABLE t1(c1 VARIANT); 3757 ** 3758 ** and the following statement to be compiled: 3759 ** 3760 ** SELECT c1 + 1, c1 FROM t1; 3761 ** 3762 ** this routine would return the string "VARIANT" for the second result 3763 ** column (i==1), and a NULL pointer for the first result column (i==0).)^ 3764 ** 3765 ** ^SQLite uses dynamic run-time typing. ^So just because a column 3766 ** is declared to contain a particular type does not mean that the 3767 ** data stored in that column is of the declared type. SQLite is 3768 ** strongly typed, but the typing is dynamic not static. ^Type 3769 ** is associated with individual values, not with the containers 3770 ** used to hold those values. 3771 */ 3772 SQLITE_API const char *SQLITE_STDCALL sqlite3_column_decltype(sqlite3_stmt*,int); 3773 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_decltype16(sqlite3_stmt*,int); 3774 3775 /* 3776 ** CAPI3REF: Evaluate An SQL Statement 3777 ** METHOD: sqlite3_stmt 3778 ** 3779 ** After a [prepared statement] has been prepared using either 3780 ** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy 3781 ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function 3782 ** must be called one or more times to evaluate the statement. 3783 ** 3784 ** The details of the behavior of the sqlite3_step() interface depend 3785 ** on whether the statement was prepared using the newer "v2" interface 3786 ** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy 3787 ** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the 3788 ** new "v2" interface is recommended for new applications but the legacy 3789 ** interface will continue to be supported. 3790 ** 3791 ** ^In the legacy interface, the return value will be either [SQLITE_BUSY], 3792 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. 3793 ** ^With the "v2" interface, any of the other [result codes] or 3794 ** [extended result codes] might be returned as well. 3795 ** 3796 ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the 3797 ** database locks it needs to do its job. ^If the statement is a [COMMIT] 3798 ** or occurs outside of an explicit transaction, then you can retry the 3799 ** statement. If the statement is not a [COMMIT] and occurs within an 3800 ** explicit transaction then you should rollback the transaction before 3801 ** continuing. 3802 ** 3803 ** ^[SQLITE_DONE] means that the statement has finished executing 3804 ** successfully. sqlite3_step() should not be called again on this virtual 3805 ** machine without first calling [sqlite3_reset()] to reset the virtual 3806 ** machine back to its initial state. 3807 ** 3808 ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] 3809 ** is returned each time a new row of data is ready for processing by the 3810 ** caller. The values may be accessed using the [column access functions]. 3811 ** sqlite3_step() is called again to retrieve the next row of data. 3812 ** 3813 ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint 3814 ** violation) has occurred. sqlite3_step() should not be called again on 3815 ** the VM. More information may be found by calling [sqlite3_errmsg()]. 3816 ** ^With the legacy interface, a more specific error code (for example, 3817 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) 3818 ** can be obtained by calling [sqlite3_reset()] on the 3819 ** [prepared statement]. ^In the "v2" interface, 3820 ** the more specific error code is returned directly by sqlite3_step(). 3821 ** 3822 ** [SQLITE_MISUSE] means that the this routine was called inappropriately. 3823 ** Perhaps it was called on a [prepared statement] that has 3824 ** already been [sqlite3_finalize | finalized] or on one that had 3825 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could 3826 ** be the case that the same database connection is being used by two or 3827 ** more threads at the same moment in time. 3828 ** 3829 ** For all versions of SQLite up to and including 3.6.23.1, a call to 3830 ** [sqlite3_reset()] was required after sqlite3_step() returned anything 3831 ** other than [SQLITE_ROW] before any subsequent invocation of 3832 ** sqlite3_step(). Failure to reset the prepared statement using 3833 ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from 3834 ** sqlite3_step(). But after version 3.6.23.1, sqlite3_step() began 3835 ** calling [sqlite3_reset()] automatically in this circumstance rather 3836 ** than returning [SQLITE_MISUSE]. This is not considered a compatibility 3837 ** break because any application that ever receives an SQLITE_MISUSE error 3838 ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option 3839 ** can be used to restore the legacy behavior. 3840 ** 3841 ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() 3842 ** API always returns a generic error code, [SQLITE_ERROR], following any 3843 ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call 3844 ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the 3845 ** specific [error codes] that better describes the error. 3846 ** We admit that this is a goofy design. The problem has been fixed 3847 ** with the "v2" interface. If you prepare all of your SQL statements 3848 ** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead 3849 ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, 3850 ** then the more specific [error codes] are returned directly 3851 ** by sqlite3_step(). The use of the "v2" interface is recommended. 3852 */ 3853 SQLITE_API int SQLITE_STDCALL sqlite3_step(sqlite3_stmt*); 3854 3855 /* 3856 ** CAPI3REF: Number of columns in a result set 3857 ** METHOD: sqlite3_stmt 3858 ** 3859 ** ^The sqlite3_data_count(P) interface returns the number of columns in the 3860 ** current row of the result set of [prepared statement] P. 3861 ** ^If prepared statement P does not have results ready to return 3862 ** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of 3863 ** interfaces) then sqlite3_data_count(P) returns 0. 3864 ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. 3865 ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to 3866 ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) 3867 ** will return non-zero if previous call to [sqlite3_step](P) returned 3868 ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] 3869 ** where it always returns zero since each step of that multi-step 3870 ** pragma returns 0 columns of data. 3871 ** 3872 ** See also: [sqlite3_column_count()] 3873 */ 3874 SQLITE_API int SQLITE_STDCALL sqlite3_data_count(sqlite3_stmt *pStmt); 3875 3876 /* 3877 ** CAPI3REF: Fundamental Datatypes 3878 ** KEYWORDS: SQLITE_TEXT 3879 ** 3880 ** ^(Every value in SQLite has one of five fundamental datatypes: 3881 ** 3882 ** <ul> 3883 ** <li> 64-bit signed integer 3884 ** <li> 64-bit IEEE floating point number 3885 ** <li> string 3886 ** <li> BLOB 3887 ** <li> NULL 3888 ** </ul>)^ 3889 ** 3890 ** These constants are codes for each of those types. 3891 ** 3892 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 3893 ** for a completely different meaning. Software that links against both 3894 ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not 3895 ** SQLITE_TEXT. 3896 */ 3897 #define SQLITE_INTEGER 1 3898 #define SQLITE_FLOAT 2 3899 #define SQLITE_BLOB 4 3900 #define SQLITE_NULL 5 3901 #ifdef SQLITE_TEXT 3902 # undef SQLITE_TEXT 3903 #else 3904 # define SQLITE_TEXT 3 3905 #endif 3906 #define SQLITE3_TEXT 3 3907 3908 /* 3909 ** CAPI3REF: Result Values From A Query 3910 ** KEYWORDS: {column access functions} 3911 ** METHOD: sqlite3_stmt 3912 ** 3913 ** ^These routines return information about a single column of the current 3914 ** result row of a query. ^In every case the first argument is a pointer 3915 ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] 3916 ** that was returned from [sqlite3_prepare_v2()] or one of its variants) 3917 ** and the second argument is the index of the column for which information 3918 ** should be returned. ^The leftmost column of the result set has the index 0. 3919 ** ^The number of columns in the result can be determined using 3920 ** [sqlite3_column_count()]. 3921 ** 3922 ** If the SQL statement does not currently point to a valid row, or if the 3923 ** column index is out of range, the result is undefined. 3924 ** These routines may only be called when the most recent call to 3925 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither 3926 ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. 3927 ** If any of these routines are called after [sqlite3_reset()] or 3928 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned 3929 ** something other than [SQLITE_ROW], the results are undefined. 3930 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] 3931 ** are called from a different thread while any of these routines 3932 ** are pending, then the results are undefined. 3933 ** 3934 ** ^The sqlite3_column_type() routine returns the 3935 ** [SQLITE_INTEGER | datatype code] for the initial data type 3936 ** of the result column. ^The returned value is one of [SQLITE_INTEGER], 3937 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value 3938 ** returned by sqlite3_column_type() is only meaningful if no type 3939 ** conversions have occurred as described below. After a type conversion, 3940 ** the value returned by sqlite3_column_type() is undefined. Future 3941 ** versions of SQLite may change the behavior of sqlite3_column_type() 3942 ** following a type conversion. 3943 ** 3944 ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 3945 ** routine returns the number of bytes in that BLOB or string. 3946 ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts 3947 ** the string to UTF-8 and then returns the number of bytes. 3948 ** ^If the result is a numeric value then sqlite3_column_bytes() uses 3949 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns 3950 ** the number of bytes in that string. 3951 ** ^If the result is NULL, then sqlite3_column_bytes() returns zero. 3952 ** 3953 ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() 3954 ** routine returns the number of bytes in that BLOB or string. 3955 ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts 3956 ** the string to UTF-16 and then returns the number of bytes. 3957 ** ^If the result is a numeric value then sqlite3_column_bytes16() uses 3958 ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns 3959 ** the number of bytes in that string. 3960 ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. 3961 ** 3962 ** ^The values returned by [sqlite3_column_bytes()] and 3963 ** [sqlite3_column_bytes16()] do not include the zero terminators at the end 3964 ** of the string. ^For clarity: the values returned by 3965 ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of 3966 ** bytes in the string, not the number of characters. 3967 ** 3968 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), 3969 ** even empty strings, are always zero-terminated. ^The return 3970 ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. 3971 ** 3972 ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an 3973 ** [unprotected sqlite3_value] object. In a multithreaded environment, 3974 ** an unprotected sqlite3_value object may only be used safely with 3975 ** [sqlite3_bind_value()] and [sqlite3_result_value()]. 3976 ** If the [unprotected sqlite3_value] object returned by 3977 ** [sqlite3_column_value()] is used in any other way, including calls 3978 ** to routines like [sqlite3_value_int()], [sqlite3_value_text()], 3979 ** or [sqlite3_value_bytes()], the behavior is not threadsafe. 3980 ** 3981 ** These routines attempt to convert the value where appropriate. ^For 3982 ** example, if the internal representation is FLOAT and a text result 3983 ** is requested, [sqlite3_snprintf()] is used internally to perform the 3984 ** conversion automatically. ^(The following table details the conversions 3985 ** that are applied: 3986 ** 3987 ** <blockquote> 3988 ** <table border="1"> 3989 ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion 3990 ** 3991 ** <tr><td> NULL <td> INTEGER <td> Result is 0 3992 ** <tr><td> NULL <td> FLOAT <td> Result is 0.0 3993 ** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer 3994 ** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer 3995 ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float 3996 ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer 3997 ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT 3998 ** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER 3999 ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float 4000 ** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB 4001 ** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER 4002 ** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL 4003 ** <tr><td> TEXT <td> BLOB <td> No change 4004 ** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER 4005 ** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL 4006 ** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed 4007 ** </table> 4008 ** </blockquote>)^ 4009 ** 4010 ** Note that when type conversions occur, pointers returned by prior 4011 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or 4012 ** sqlite3_column_text16() may be invalidated. 4013 ** Type conversions and pointer invalidations might occur 4014 ** in the following cases: 4015 ** 4016 ** <ul> 4017 ** <li> The initial content is a BLOB and sqlite3_column_text() or 4018 ** sqlite3_column_text16() is called. A zero-terminator might 4019 ** need to be added to the string.</li> 4020 ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or 4021 ** sqlite3_column_text16() is called. The content must be converted 4022 ** to UTF-16.</li> 4023 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or 4024 ** sqlite3_column_text() is called. The content must be converted 4025 ** to UTF-8.</li> 4026 ** </ul> 4027 ** 4028 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do 4029 ** not invalidate a prior pointer, though of course the content of the buffer 4030 ** that the prior pointer references will have been modified. Other kinds 4031 ** of conversion are done in place when it is possible, but sometimes they 4032 ** are not possible and in those cases prior pointers are invalidated. 4033 ** 4034 ** The safest policy is to invoke these routines 4035 ** in one of the following ways: 4036 ** 4037 ** <ul> 4038 ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> 4039 ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> 4040 ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> 4041 ** </ul> 4042 ** 4043 ** In other words, you should call sqlite3_column_text(), 4044 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result 4045 ** into the desired format, then invoke sqlite3_column_bytes() or 4046 ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls 4047 ** to sqlite3_column_text() or sqlite3_column_blob() with calls to 4048 ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() 4049 ** with calls to sqlite3_column_bytes(). 4050 ** 4051 ** ^The pointers returned are valid until a type conversion occurs as 4052 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or 4053 ** [sqlite3_finalize()] is called. ^The memory space used to hold strings 4054 ** and BLOBs is freed automatically. Do <em>not</em> pass the pointers returned 4055 ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 4056 ** [sqlite3_free()]. 4057 ** 4058 ** ^(If a memory allocation error occurs during the evaluation of any 4059 ** of these routines, a default value is returned. The default value 4060 ** is either the integer 0, the floating point number 0.0, or a NULL 4061 ** pointer. Subsequent calls to [sqlite3_errcode()] will return 4062 ** [SQLITE_NOMEM].)^ 4063 */ 4064 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_blob(sqlite3_stmt*, int iCol); 4065 SQLITE_API int SQLITE_STDCALL sqlite3_column_bytes(sqlite3_stmt*, int iCol); 4066 SQLITE_API int SQLITE_STDCALL sqlite3_column_bytes16(sqlite3_stmt*, int iCol); 4067 SQLITE_API double SQLITE_STDCALL sqlite3_column_double(sqlite3_stmt*, int iCol); 4068 SQLITE_API int SQLITE_STDCALL sqlite3_column_int(sqlite3_stmt*, int iCol); 4069 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_column_int64(sqlite3_stmt*, int iCol); 4070 SQLITE_API const unsigned char *SQLITE_STDCALL sqlite3_column_text(sqlite3_stmt*, int iCol); 4071 SQLITE_API const void *SQLITE_STDCALL sqlite3_column_text16(sqlite3_stmt*, int iCol); 4072 SQLITE_API int SQLITE_STDCALL sqlite3_column_type(sqlite3_stmt*, int iCol); 4073 SQLITE_API sqlite3_value *SQLITE_STDCALL sqlite3_column_value(sqlite3_stmt*, int iCol); 4074 4075 /* 4076 ** CAPI3REF: Destroy A Prepared Statement Object 4077 ** DESTRUCTOR: sqlite3_stmt 4078 ** 4079 ** ^The sqlite3_finalize() function is called to delete a [prepared statement]. 4080 ** ^If the most recent evaluation of the statement encountered no errors 4081 ** or if the statement is never been evaluated, then sqlite3_finalize() returns 4082 ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then 4083 ** sqlite3_finalize(S) returns the appropriate [error code] or 4084 ** [extended error code]. 4085 ** 4086 ** ^The sqlite3_finalize(S) routine can be called at any point during 4087 ** the life cycle of [prepared statement] S: 4088 ** before statement S is ever evaluated, after 4089 ** one or more calls to [sqlite3_reset()], or after any call 4090 ** to [sqlite3_step()] regardless of whether or not the statement has 4091 ** completed execution. 4092 ** 4093 ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. 4094 ** 4095 ** The application must finalize every [prepared statement] in order to avoid 4096 ** resource leaks. It is a grievous error for the application to try to use 4097 ** a prepared statement after it has been finalized. Any use of a prepared 4098 ** statement after it has been finalized can result in undefined and 4099 ** undesirable behavior such as segfaults and heap corruption. 4100 */ 4101 SQLITE_API int SQLITE_STDCALL sqlite3_finalize(sqlite3_stmt *pStmt); 4102 4103 /* 4104 ** CAPI3REF: Reset A Prepared Statement Object 4105 ** METHOD: sqlite3_stmt 4106 ** 4107 ** The sqlite3_reset() function is called to reset a [prepared statement] 4108 ** object back to its initial state, ready to be re-executed. 4109 ** ^Any SQL statement variables that had values bound to them using 4110 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. 4111 ** Use [sqlite3_clear_bindings()] to reset the bindings. 4112 ** 4113 ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S 4114 ** back to the beginning of its program. 4115 ** 4116 ** ^If the most recent call to [sqlite3_step(S)] for the 4117 ** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], 4118 ** or if [sqlite3_step(S)] has never before been called on S, 4119 ** then [sqlite3_reset(S)] returns [SQLITE_OK]. 4120 ** 4121 ** ^If the most recent call to [sqlite3_step(S)] for the 4122 ** [prepared statement] S indicated an error, then 4123 ** [sqlite3_reset(S)] returns an appropriate [error code]. 4124 ** 4125 ** ^The [sqlite3_reset(S)] interface does not change the values 4126 ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. 4127 */ 4128 SQLITE_API int SQLITE_STDCALL sqlite3_reset(sqlite3_stmt *pStmt); 4129 4130 /* 4131 ** CAPI3REF: Create Or Redefine SQL Functions 4132 ** KEYWORDS: {function creation routines} 4133 ** KEYWORDS: {application-defined SQL function} 4134 ** KEYWORDS: {application-defined SQL functions} 4135 ** METHOD: sqlite3 4136 ** 4137 ** ^These functions (collectively known as "function creation routines") 4138 ** are used to add SQL functions or aggregates or to redefine the behavior 4139 ** of existing SQL functions or aggregates. The only differences between 4140 ** these routines are the text encoding expected for 4141 ** the second parameter (the name of the function being created) 4142 ** and the presence or absence of a destructor callback for 4143 ** the application data pointer. 4144 ** 4145 ** ^The first parameter is the [database connection] to which the SQL 4146 ** function is to be added. ^If an application uses more than one database 4147 ** connection then application-defined SQL functions must be added 4148 ** to each database connection separately. 4149 ** 4150 ** ^The second parameter is the name of the SQL function to be created or 4151 ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 4152 ** representation, exclusive of the zero-terminator. ^Note that the name 4153 ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. 4154 ** ^Any attempt to create a function with a longer name 4155 ** will result in [SQLITE_MISUSE] being returned. 4156 ** 4157 ** ^The third parameter (nArg) 4158 ** is the number of arguments that the SQL function or 4159 ** aggregate takes. ^If this parameter is -1, then the SQL function or 4160 ** aggregate may take any number of arguments between 0 and the limit 4161 ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third 4162 ** parameter is less than -1 or greater than 127 then the behavior is 4163 ** undefined. 4164 ** 4165 ** ^The fourth parameter, eTextRep, specifies what 4166 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for 4167 ** its parameters. The application should set this parameter to 4168 ** [SQLITE_UTF16LE] if the function implementation invokes 4169 ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the 4170 ** implementation invokes [sqlite3_value_text16be()] on an input, or 4171 ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] 4172 ** otherwise. ^The same SQL function may be registered multiple times using 4173 ** different preferred text encodings, with different implementations for 4174 ** each encoding. 4175 ** ^When multiple implementations of the same function are available, SQLite 4176 ** will pick the one that involves the least amount of data conversion. 4177 ** 4178 ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] 4179 ** to signal that the function will always return the same result given 4180 ** the same inputs within a single SQL statement. Most SQL functions are 4181 ** deterministic. The built-in [random()] SQL function is an example of a 4182 ** function that is not deterministic. The SQLite query planner is able to 4183 ** perform additional optimizations on deterministic functions, so use 4184 ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. 4185 ** 4186 ** ^(The fifth parameter is an arbitrary pointer. The implementation of the 4187 ** function can gain access to this pointer using [sqlite3_user_data()].)^ 4188 ** 4189 ** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are 4190 ** pointers to C-language functions that implement the SQL function or 4191 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc 4192 ** callback only; NULL pointers must be passed as the xStep and xFinal 4193 ** parameters. ^An aggregate SQL function requires an implementation of xStep 4194 ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing 4195 ** SQL function or aggregate, pass NULL pointers for all three function 4196 ** callbacks. 4197 ** 4198 ** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL, 4199 ** then it is destructor for the application data pointer. 4200 ** The destructor is invoked when the function is deleted, either by being 4201 ** overloaded or when the database connection closes.)^ 4202 ** ^The destructor is also invoked if the call to 4203 ** sqlite3_create_function_v2() fails. 4204 ** ^When the destructor callback of the tenth parameter is invoked, it 4205 ** is passed a single argument which is a copy of the application data 4206 ** pointer which was the fifth parameter to sqlite3_create_function_v2(). 4207 ** 4208 ** ^It is permitted to register multiple implementations of the same 4209 ** functions with the same name but with either differing numbers of 4210 ** arguments or differing preferred text encodings. ^SQLite will use 4211 ** the implementation that most closely matches the way in which the 4212 ** SQL function is used. ^A function implementation with a non-negative 4213 ** nArg parameter is a better match than a function implementation with 4214 ** a negative nArg. ^A function where the preferred text encoding 4215 ** matches the database encoding is a better 4216 ** match than a function where the encoding is different. 4217 ** ^A function where the encoding difference is between UTF16le and UTF16be 4218 ** is a closer match than a function where the encoding difference is 4219 ** between UTF8 and UTF16. 4220 ** 4221 ** ^Built-in functions may be overloaded by new application-defined functions. 4222 ** 4223 ** ^An application-defined function is permitted to call other 4224 ** SQLite interfaces. However, such calls must not 4225 ** close the database connection nor finalize or reset the prepared 4226 ** statement in which the function is running. 4227 */ 4228 SQLITE_API int SQLITE_STDCALL sqlite3_create_function( 4229 sqlite3 *db, 4230 const char *zFunctionName, 4231 int nArg, 4232 int eTextRep, 4233 void *pApp, 4234 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 4235 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 4236 void (*xFinal)(sqlite3_context*) 4237 ); 4238 SQLITE_API int SQLITE_STDCALL sqlite3_create_function16( 4239 sqlite3 *db, 4240 const void *zFunctionName, 4241 int nArg, 4242 int eTextRep, 4243 void *pApp, 4244 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 4245 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 4246 void (*xFinal)(sqlite3_context*) 4247 ); 4248 SQLITE_API int SQLITE_STDCALL sqlite3_create_function_v2( 4249 sqlite3 *db, 4250 const char *zFunctionName, 4251 int nArg, 4252 int eTextRep, 4253 void *pApp, 4254 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 4255 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 4256 void (*xFinal)(sqlite3_context*), 4257 void(*xDestroy)(void*) 4258 ); 4259 4260 /* 4261 ** CAPI3REF: Text Encodings 4262 ** 4263 ** These constant define integer codes that represent the various 4264 ** text encodings supported by SQLite. 4265 */ 4266 #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ 4267 #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ 4268 #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ 4269 #define SQLITE_UTF16 4 /* Use native byte order */ 4270 #define SQLITE_ANY 5 /* Deprecated */ 4271 #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ 4272 4273 /* 4274 ** CAPI3REF: Function Flags 4275 ** 4276 ** These constants may be ORed together with the 4277 ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument 4278 ** to [sqlite3_create_function()], [sqlite3_create_function16()], or 4279 ** [sqlite3_create_function_v2()]. 4280 */ 4281 #define SQLITE_DETERMINISTIC 0x800 4282 4283 /* 4284 ** CAPI3REF: Deprecated Functions 4285 ** DEPRECATED 4286 ** 4287 ** These functions are [deprecated]. In order to maintain 4288 ** backwards compatibility with older code, these functions continue 4289 ** to be supported. However, new applications should avoid 4290 ** the use of these functions. To encourage programmers to avoid 4291 ** these functions, we will not explain what they do. 4292 */ 4293 #ifndef SQLITE_OMIT_DEPRECATED 4294 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_aggregate_count(sqlite3_context*); 4295 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_expired(sqlite3_stmt*); 4296 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); 4297 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_global_recover(void); 4298 SQLITE_API SQLITE_DEPRECATED void SQLITE_STDCALL sqlite3_thread_cleanup(void); 4299 SQLITE_API SQLITE_DEPRECATED int SQLITE_STDCALL sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), 4300 void*,sqlite3_int64); 4301 #endif 4302 4303 /* 4304 ** CAPI3REF: Obtaining SQL Values 4305 ** METHOD: sqlite3_value 4306 ** 4307 ** The C-language implementation of SQL functions and aggregates uses 4308 ** this set of interface routines to access the parameter values on 4309 ** the function or aggregate. 4310 ** 4311 ** The xFunc (for scalar functions) or xStep (for aggregates) parameters 4312 ** to [sqlite3_create_function()] and [sqlite3_create_function16()] 4313 ** define callbacks that implement the SQL functions and aggregates. 4314 ** The 3rd parameter to these callbacks is an array of pointers to 4315 ** [protected sqlite3_value] objects. There is one [sqlite3_value] object for 4316 ** each parameter to the SQL function. These routines are used to 4317 ** extract values from the [sqlite3_value] objects. 4318 ** 4319 ** These routines work only with [protected sqlite3_value] objects. 4320 ** Any attempt to use these routines on an [unprotected sqlite3_value] 4321 ** object results in undefined behavior. 4322 ** 4323 ** ^These routines work just like the corresponding [column access functions] 4324 ** except that these routines take a single [protected sqlite3_value] object 4325 ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. 4326 ** 4327 ** ^The sqlite3_value_text16() interface extracts a UTF-16 string 4328 ** in the native byte-order of the host machine. ^The 4329 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces 4330 ** extract UTF-16 strings as big-endian and little-endian respectively. 4331 ** 4332 ** ^(The sqlite3_value_numeric_type() interface attempts to apply 4333 ** numeric affinity to the value. This means that an attempt is 4334 ** made to convert the value to an integer or floating point. If 4335 ** such a conversion is possible without loss of information (in other 4336 ** words, if the value is a string that looks like a number) 4337 ** then the conversion is performed. Otherwise no conversion occurs. 4338 ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ 4339 ** 4340 ** Please pay particular attention to the fact that the pointer returned 4341 ** from [sqlite3_value_blob()], [sqlite3_value_text()], or 4342 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to 4343 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], 4344 ** or [sqlite3_value_text16()]. 4345 ** 4346 ** These routines must be called from the same thread as 4347 ** the SQL function that supplied the [sqlite3_value*] parameters. 4348 */ 4349 SQLITE_API const void *SQLITE_STDCALL sqlite3_value_blob(sqlite3_value*); 4350 SQLITE_API int SQLITE_STDCALL sqlite3_value_bytes(sqlite3_value*); 4351 SQLITE_API int SQLITE_STDCALL sqlite3_value_bytes16(sqlite3_value*); 4352 SQLITE_API double SQLITE_STDCALL sqlite3_value_double(sqlite3_value*); 4353 SQLITE_API int SQLITE_STDCALL sqlite3_value_int(sqlite3_value*); 4354 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_value_int64(sqlite3_value*); 4355 SQLITE_API const unsigned char *SQLITE_STDCALL sqlite3_value_text(sqlite3_value*); 4356 SQLITE_API const void *SQLITE_STDCALL sqlite3_value_text16(sqlite3_value*); 4357 SQLITE_API const void *SQLITE_STDCALL sqlite3_value_text16le(sqlite3_value*); 4358 SQLITE_API const void *SQLITE_STDCALL sqlite3_value_text16be(sqlite3_value*); 4359 SQLITE_API int SQLITE_STDCALL sqlite3_value_type(sqlite3_value*); 4360 SQLITE_API int SQLITE_STDCALL sqlite3_value_numeric_type(sqlite3_value*); 4361 4362 /* 4363 ** CAPI3REF: Finding The Subtype Of SQL Values 4364 ** METHOD: sqlite3_value 4365 ** 4366 ** The sqlite3_value_subtype(V) function returns the subtype for 4367 ** an [application-defined SQL function] argument V. The subtype 4368 ** information can be used to pass a limited amount of context from 4369 ** one SQL function to another. Use the [sqlite3_result_subtype()] 4370 ** routine to set the subtype for the return value of an SQL function. 4371 ** 4372 ** SQLite makes no use of subtype itself. It merely passes the subtype 4373 ** from the result of one [application-defined SQL function] into the 4374 ** input of another. 4375 */ 4376 SQLITE_API unsigned int SQLITE_STDCALL sqlite3_value_subtype(sqlite3_value*); 4377 4378 /* 4379 ** CAPI3REF: Copy And Free SQL Values 4380 ** METHOD: sqlite3_value 4381 ** 4382 ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] 4383 ** object D and returns a pointer to that copy. ^The [sqlite3_value] returned 4384 ** is a [protected sqlite3_value] object even if the input is not. 4385 ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a 4386 ** memory allocation fails. 4387 ** 4388 ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object 4389 ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer 4390 ** then sqlite3_value_free(V) is a harmless no-op. 4391 */ 4392 SQLITE_API SQLITE_EXPERIMENTAL sqlite3_value *SQLITE_STDCALL sqlite3_value_dup(const sqlite3_value*); 4393 SQLITE_API SQLITE_EXPERIMENTAL void SQLITE_STDCALL sqlite3_value_free(sqlite3_value*); 4394 4395 /* 4396 ** CAPI3REF: Obtain Aggregate Function Context 4397 ** METHOD: sqlite3_context 4398 ** 4399 ** Implementations of aggregate SQL functions use this 4400 ** routine to allocate memory for storing their state. 4401 ** 4402 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called 4403 ** for a particular aggregate function, SQLite 4404 ** allocates N of memory, zeroes out that memory, and returns a pointer 4405 ** to the new memory. ^On second and subsequent calls to 4406 ** sqlite3_aggregate_context() for the same aggregate function instance, 4407 ** the same buffer is returned. Sqlite3_aggregate_context() is normally 4408 ** called once for each invocation of the xStep callback and then one 4409 ** last time when the xFinal callback is invoked. ^(When no rows match 4410 ** an aggregate query, the xStep() callback of the aggregate function 4411 ** implementation is never called and xFinal() is called exactly once. 4412 ** In those cases, sqlite3_aggregate_context() might be called for the 4413 ** first time from within xFinal().)^ 4414 ** 4415 ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 4416 ** when first called if N is less than or equal to zero or if a memory 4417 ** allocate error occurs. 4418 ** 4419 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is 4420 ** determined by the N parameter on first successful call. Changing the 4421 ** value of N in subsequent call to sqlite3_aggregate_context() within 4422 ** the same aggregate function instance will not resize the memory 4423 ** allocation.)^ Within the xFinal callback, it is customary to set 4424 ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 4425 ** pointless memory allocations occur. 4426 ** 4427 ** ^SQLite automatically frees the memory allocated by 4428 ** sqlite3_aggregate_context() when the aggregate query concludes. 4429 ** 4430 ** The first parameter must be a copy of the 4431 ** [sqlite3_context | SQL function context] that is the first parameter 4432 ** to the xStep or xFinal callback routine that implements the aggregate 4433 ** function. 4434 ** 4435 ** This routine must be called from the same thread in which 4436 ** the aggregate SQL function is running. 4437 */ 4438 SQLITE_API void *SQLITE_STDCALL sqlite3_aggregate_context(sqlite3_context*, int nBytes); 4439 4440 /* 4441 ** CAPI3REF: User Data For Functions 4442 ** METHOD: sqlite3_context 4443 ** 4444 ** ^The sqlite3_user_data() interface returns a copy of 4445 ** the pointer that was the pUserData parameter (the 5th parameter) 4446 ** of the [sqlite3_create_function()] 4447 ** and [sqlite3_create_function16()] routines that originally 4448 ** registered the application defined function. 4449 ** 4450 ** This routine must be called from the same thread in which 4451 ** the application-defined function is running. 4452 */ 4453 SQLITE_API void *SQLITE_STDCALL sqlite3_user_data(sqlite3_context*); 4454 4455 /* 4456 ** CAPI3REF: Database Connection For Functions 4457 ** METHOD: sqlite3_context 4458 ** 4459 ** ^The sqlite3_context_db_handle() interface returns a copy of 4460 ** the pointer to the [database connection] (the 1st parameter) 4461 ** of the [sqlite3_create_function()] 4462 ** and [sqlite3_create_function16()] routines that originally 4463 ** registered the application defined function. 4464 */ 4465 SQLITE_API sqlite3 *SQLITE_STDCALL sqlite3_context_db_handle(sqlite3_context*); 4466 4467 /* 4468 ** CAPI3REF: Function Auxiliary Data 4469 ** METHOD: sqlite3_context 4470 ** 4471 ** These functions may be used by (non-aggregate) SQL functions to 4472 ** associate metadata with argument values. If the same value is passed to 4473 ** multiple invocations of the same SQL function during query execution, under 4474 ** some circumstances the associated metadata may be preserved. An example 4475 ** of where this might be useful is in a regular-expression matching 4476 ** function. The compiled version of the regular expression can be stored as 4477 ** metadata associated with the pattern string. 4478 ** Then as long as the pattern string remains the same, 4479 ** the compiled regular expression can be reused on multiple 4480 ** invocations of the same function. 4481 ** 4482 ** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata 4483 ** associated by the sqlite3_set_auxdata() function with the Nth argument 4484 ** value to the application-defined function. ^If there is no metadata 4485 ** associated with the function argument, this sqlite3_get_auxdata() interface 4486 ** returns a NULL pointer. 4487 ** 4488 ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th 4489 ** argument of the application-defined function. ^Subsequent 4490 ** calls to sqlite3_get_auxdata(C,N) return P from the most recent 4491 ** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or 4492 ** NULL if the metadata has been discarded. 4493 ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, 4494 ** SQLite will invoke the destructor function X with parameter P exactly 4495 ** once, when the metadata is discarded. 4496 ** SQLite is free to discard the metadata at any time, including: <ul> 4497 ** <li> when the corresponding function parameter changes, or 4498 ** <li> when [sqlite3_reset()] or [sqlite3_finalize()] is called for the 4499 ** SQL statement, or 4500 ** <li> when sqlite3_set_auxdata() is invoked again on the same parameter, or 4501 ** <li> during the original sqlite3_set_auxdata() call when a memory 4502 ** allocation error occurs. </ul>)^ 4503 ** 4504 ** Note the last bullet in particular. The destructor X in 4505 ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the 4506 ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() 4507 ** should be called near the end of the function implementation and the 4508 ** function implementation should not make any use of P after 4509 ** sqlite3_set_auxdata() has been called. 4510 ** 4511 ** ^(In practice, metadata is preserved between function calls for 4512 ** function parameters that are compile-time constants, including literal 4513 ** values and [parameters] and expressions composed from the same.)^ 4514 ** 4515 ** These routines must be called from the same thread in which 4516 ** the SQL function is running. 4517 */ 4518 SQLITE_API void *SQLITE_STDCALL sqlite3_get_auxdata(sqlite3_context*, int N); 4519 SQLITE_API void SQLITE_STDCALL sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); 4520 4521 4522 /* 4523 ** CAPI3REF: Constants Defining Special Destructor Behavior 4524 ** 4525 ** These are special values for the destructor that is passed in as the 4526 ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor 4527 ** argument is SQLITE_STATIC, it means that the content pointer is constant 4528 ** and will never change. It does not need to be destroyed. ^The 4529 ** SQLITE_TRANSIENT value means that the content will likely change in 4530 ** the near future and that SQLite should make its own private copy of 4531 ** the content before returning. 4532 ** 4533 ** The typedef is necessary to work around problems in certain 4534 ** C++ compilers. 4535 */ 4536 typedef void (*sqlite3_destructor_type)(void*); 4537 #define SQLITE_STATIC ((sqlite3_destructor_type)0) 4538 #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) 4539 4540 /* 4541 ** CAPI3REF: Setting The Result Of An SQL Function 4542 ** METHOD: sqlite3_context 4543 ** 4544 ** These routines are used by the xFunc or xFinal callbacks that 4545 ** implement SQL functions and aggregates. See 4546 ** [sqlite3_create_function()] and [sqlite3_create_function16()] 4547 ** for additional information. 4548 ** 4549 ** These functions work very much like the [parameter binding] family of 4550 ** functions used to bind values to host parameters in prepared statements. 4551 ** Refer to the [SQL parameter] documentation for additional information. 4552 ** 4553 ** ^The sqlite3_result_blob() interface sets the result from 4554 ** an application-defined function to be the BLOB whose content is pointed 4555 ** to by the second parameter and which is N bytes long where N is the 4556 ** third parameter. 4557 ** 4558 ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) 4559 ** interfaces set the result of the application-defined function to be 4560 ** a BLOB containing all zero bytes and N bytes in size. 4561 ** 4562 ** ^The sqlite3_result_double() interface sets the result from 4563 ** an application-defined function to be a floating point value specified 4564 ** by its 2nd argument. 4565 ** 4566 ** ^The sqlite3_result_error() and sqlite3_result_error16() functions 4567 ** cause the implemented SQL function to throw an exception. 4568 ** ^SQLite uses the string pointed to by the 4569 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() 4570 ** as the text of an error message. ^SQLite interprets the error 4571 ** message string from sqlite3_result_error() as UTF-8. ^SQLite 4572 ** interprets the string from sqlite3_result_error16() as UTF-16 in native 4573 ** byte order. ^If the third parameter to sqlite3_result_error() 4574 ** or sqlite3_result_error16() is negative then SQLite takes as the error 4575 ** message all text up through the first zero character. 4576 ** ^If the third parameter to sqlite3_result_error() or 4577 ** sqlite3_result_error16() is non-negative then SQLite takes that many 4578 ** bytes (not characters) from the 2nd parameter as the error message. 4579 ** ^The sqlite3_result_error() and sqlite3_result_error16() 4580 ** routines make a private copy of the error message text before 4581 ** they return. Hence, the calling function can deallocate or 4582 ** modify the text after they return without harm. 4583 ** ^The sqlite3_result_error_code() function changes the error code 4584 ** returned by SQLite as a result of an error in a function. ^By default, 4585 ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() 4586 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. 4587 ** 4588 ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an 4589 ** error indicating that a string or BLOB is too long to represent. 4590 ** 4591 ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an 4592 ** error indicating that a memory allocation failed. 4593 ** 4594 ** ^The sqlite3_result_int() interface sets the return value 4595 ** of the application-defined function to be the 32-bit signed integer 4596 ** value given in the 2nd argument. 4597 ** ^The sqlite3_result_int64() interface sets the return value 4598 ** of the application-defined function to be the 64-bit signed integer 4599 ** value given in the 2nd argument. 4600 ** 4601 ** ^The sqlite3_result_null() interface sets the return value 4602 ** of the application-defined function to be NULL. 4603 ** 4604 ** ^The sqlite3_result_text(), sqlite3_result_text16(), 4605 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces 4606 ** set the return value of the application-defined function to be 4607 ** a text string which is represented as UTF-8, UTF-16 native byte order, 4608 ** UTF-16 little endian, or UTF-16 big endian, respectively. 4609 ** ^The sqlite3_result_text64() interface sets the return value of an 4610 ** application-defined function to be a text string in an encoding 4611 ** specified by the fifth (and last) parameter, which must be one 4612 ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. 4613 ** ^SQLite takes the text result from the application from 4614 ** the 2nd parameter of the sqlite3_result_text* interfaces. 4615 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces 4616 ** is negative, then SQLite takes result text from the 2nd parameter 4617 ** through the first zero character. 4618 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces 4619 ** is non-negative, then as many bytes (not characters) of the text 4620 ** pointed to by the 2nd parameter are taken as the application-defined 4621 ** function result. If the 3rd parameter is non-negative, then it 4622 ** must be the byte offset into the string where the NUL terminator would 4623 ** appear if the string where NUL terminated. If any NUL characters occur 4624 ** in the string at a byte offset that is less than the value of the 3rd 4625 ** parameter, then the resulting string will contain embedded NULs and the 4626 ** result of expressions operating on strings with embedded NULs is undefined. 4627 ** ^If the 4th parameter to the sqlite3_result_text* interfaces 4628 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that 4629 ** function as the destructor on the text or BLOB result when it has 4630 ** finished using that result. 4631 ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to 4632 ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite 4633 ** assumes that the text or BLOB result is in constant space and does not 4634 ** copy the content of the parameter nor call a destructor on the content 4635 ** when it has finished using that result. 4636 ** ^If the 4th parameter to the sqlite3_result_text* interfaces 4637 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT 4638 ** then SQLite makes a copy of the result into space obtained from 4639 ** from [sqlite3_malloc()] before it returns. 4640 ** 4641 ** ^The sqlite3_result_value() interface sets the result of 4642 ** the application-defined function to be a copy of the 4643 ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The 4644 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] 4645 ** so that the [sqlite3_value] specified in the parameter may change or 4646 ** be deallocated after sqlite3_result_value() returns without harm. 4647 ** ^A [protected sqlite3_value] object may always be used where an 4648 ** [unprotected sqlite3_value] object is required, so either 4649 ** kind of [sqlite3_value] object can be used with this interface. 4650 ** 4651 ** If these routines are called from within the different thread 4652 ** than the one containing the application-defined function that received 4653 ** the [sqlite3_context] pointer, the results are undefined. 4654 */ 4655 SQLITE_API void SQLITE_STDCALL sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); 4656 SQLITE_API void SQLITE_STDCALL sqlite3_result_blob64(sqlite3_context*,const void*, 4657 sqlite3_uint64,void(*)(void*)); 4658 SQLITE_API void SQLITE_STDCALL sqlite3_result_double(sqlite3_context*, double); 4659 SQLITE_API void SQLITE_STDCALL sqlite3_result_error(sqlite3_context*, const char*, int); 4660 SQLITE_API void SQLITE_STDCALL sqlite3_result_error16(sqlite3_context*, const void*, int); 4661 SQLITE_API void SQLITE_STDCALL sqlite3_result_error_toobig(sqlite3_context*); 4662 SQLITE_API void SQLITE_STDCALL sqlite3_result_error_nomem(sqlite3_context*); 4663 SQLITE_API void SQLITE_STDCALL sqlite3_result_error_code(sqlite3_context*, int); 4664 SQLITE_API void SQLITE_STDCALL sqlite3_result_int(sqlite3_context*, int); 4665 SQLITE_API void SQLITE_STDCALL sqlite3_result_int64(sqlite3_context*, sqlite3_int64); 4666 SQLITE_API void SQLITE_STDCALL sqlite3_result_null(sqlite3_context*); 4667 SQLITE_API void SQLITE_STDCALL sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); 4668 SQLITE_API void SQLITE_STDCALL sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, 4669 void(*)(void*), unsigned char encoding); 4670 SQLITE_API void SQLITE_STDCALL sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); 4671 SQLITE_API void SQLITE_STDCALL sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); 4672 SQLITE_API void SQLITE_STDCALL sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); 4673 SQLITE_API void SQLITE_STDCALL sqlite3_result_value(sqlite3_context*, sqlite3_value*); 4674 SQLITE_API void SQLITE_STDCALL sqlite3_result_zeroblob(sqlite3_context*, int n); 4675 SQLITE_API int SQLITE_STDCALL sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); 4676 4677 4678 /* 4679 ** CAPI3REF: Setting The Subtype Of An SQL Function 4680 ** METHOD: sqlite3_context 4681 ** 4682 ** The sqlite3_result_subtype(C,T) function causes the subtype of 4683 ** the result from the [application-defined SQL function] with 4684 ** [sqlite3_context] C to be the value T. Only the lower 8 bits 4685 ** of the subtype T are preserved in current versions of SQLite; 4686 ** higher order bits are discarded. 4687 ** The number of subtype bytes preserved by SQLite might increase 4688 ** in future releases of SQLite. 4689 */ 4690 SQLITE_API void SQLITE_STDCALL sqlite3_result_subtype(sqlite3_context*,unsigned int); 4691 4692 /* 4693 ** CAPI3REF: Define New Collating Sequences 4694 ** METHOD: sqlite3 4695 ** 4696 ** ^These functions add, remove, or modify a [collation] associated 4697 ** with the [database connection] specified as the first argument. 4698 ** 4699 ** ^The name of the collation is a UTF-8 string 4700 ** for sqlite3_create_collation() and sqlite3_create_collation_v2() 4701 ** and a UTF-16 string in native byte order for sqlite3_create_collation16(). 4702 ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are 4703 ** considered to be the same name. 4704 ** 4705 ** ^(The third argument (eTextRep) must be one of the constants: 4706 ** <ul> 4707 ** <li> [SQLITE_UTF8], 4708 ** <li> [SQLITE_UTF16LE], 4709 ** <li> [SQLITE_UTF16BE], 4710 ** <li> [SQLITE_UTF16], or 4711 ** <li> [SQLITE_UTF16_ALIGNED]. 4712 ** </ul>)^ 4713 ** ^The eTextRep argument determines the encoding of strings passed 4714 ** to the collating function callback, xCallback. 4715 ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep 4716 ** force strings to be UTF16 with native byte order. 4717 ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin 4718 ** on an even byte address. 4719 ** 4720 ** ^The fourth argument, pArg, is an application data pointer that is passed 4721 ** through as the first argument to the collating function callback. 4722 ** 4723 ** ^The fifth argument, xCallback, is a pointer to the collating function. 4724 ** ^Multiple collating functions can be registered using the same name but 4725 ** with different eTextRep parameters and SQLite will use whichever 4726 ** function requires the least amount of data transformation. 4727 ** ^If the xCallback argument is NULL then the collating function is 4728 ** deleted. ^When all collating functions having the same name are deleted, 4729 ** that collation is no longer usable. 4730 ** 4731 ** ^The collating function callback is invoked with a copy of the pArg 4732 ** application data pointer and with two strings in the encoding specified 4733 ** by the eTextRep argument. The collating function must return an 4734 ** integer that is negative, zero, or positive 4735 ** if the first string is less than, equal to, or greater than the second, 4736 ** respectively. A collating function must always return the same answer 4737 ** given the same inputs. If two or more collating functions are registered 4738 ** to the same collation name (using different eTextRep values) then all 4739 ** must give an equivalent answer when invoked with equivalent strings. 4740 ** The collating function must obey the following properties for all 4741 ** strings A, B, and C: 4742 ** 4743 ** <ol> 4744 ** <li> If A==B then B==A. 4745 ** <li> If A==B and B==C then A==C. 4746 ** <li> If A<B THEN B>A. 4747 ** <li> If A<B and B<C then A<C. 4748 ** </ol> 4749 ** 4750 ** If a collating function fails any of the above constraints and that 4751 ** collating function is registered and used, then the behavior of SQLite 4752 ** is undefined. 4753 ** 4754 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() 4755 ** with the addition that the xDestroy callback is invoked on pArg when 4756 ** the collating function is deleted. 4757 ** ^Collating functions are deleted when they are overridden by later 4758 ** calls to the collation creation functions or when the 4759 ** [database connection] is closed using [sqlite3_close()]. 4760 ** 4761 ** ^The xDestroy callback is <u>not</u> called if the 4762 ** sqlite3_create_collation_v2() function fails. Applications that invoke 4763 ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 4764 ** check the return code and dispose of the application data pointer 4765 ** themselves rather than expecting SQLite to deal with it for them. 4766 ** This is different from every other SQLite interface. The inconsistency 4767 ** is unfortunate but cannot be changed without breaking backwards 4768 ** compatibility. 4769 ** 4770 ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. 4771 */ 4772 SQLITE_API int SQLITE_STDCALL sqlite3_create_collation( 4773 sqlite3*, 4774 const char *zName, 4775 int eTextRep, 4776 void *pArg, 4777 int(*xCompare)(void*,int,const void*,int,const void*) 4778 ); 4779 SQLITE_API int SQLITE_STDCALL sqlite3_create_collation_v2( 4780 sqlite3*, 4781 const char *zName, 4782 int eTextRep, 4783 void *pArg, 4784 int(*xCompare)(void*,int,const void*,int,const void*), 4785 void(*xDestroy)(void*) 4786 ); 4787 SQLITE_API int SQLITE_STDCALL sqlite3_create_collation16( 4788 sqlite3*, 4789 const void *zName, 4790 int eTextRep, 4791 void *pArg, 4792 int(*xCompare)(void*,int,const void*,int,const void*) 4793 ); 4794 4795 /* 4796 ** CAPI3REF: Collation Needed Callbacks 4797 ** METHOD: sqlite3 4798 ** 4799 ** ^To avoid having to register all collation sequences before a database 4800 ** can be used, a single callback function may be registered with the 4801 ** [database connection] to be invoked whenever an undefined collation 4802 ** sequence is required. 4803 ** 4804 ** ^If the function is registered using the sqlite3_collation_needed() API, 4805 ** then it is passed the names of undefined collation sequences as strings 4806 ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, 4807 ** the names are passed as UTF-16 in machine native byte order. 4808 ** ^A call to either function replaces the existing collation-needed callback. 4809 ** 4810 ** ^(When the callback is invoked, the first argument passed is a copy 4811 ** of the second argument to sqlite3_collation_needed() or 4812 ** sqlite3_collation_needed16(). The second argument is the database 4813 ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], 4814 ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation 4815 ** sequence function required. The fourth parameter is the name of the 4816 ** required collation sequence.)^ 4817 ** 4818 ** The callback function should register the desired collation using 4819 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or 4820 ** [sqlite3_create_collation_v2()]. 4821 */ 4822 SQLITE_API int SQLITE_STDCALL sqlite3_collation_needed( 4823 sqlite3*, 4824 void*, 4825 void(*)(void*,sqlite3*,int eTextRep,const char*) 4826 ); 4827 SQLITE_API int SQLITE_STDCALL sqlite3_collation_needed16( 4828 sqlite3*, 4829 void*, 4830 void(*)(void*,sqlite3*,int eTextRep,const void*) 4831 ); 4832 4833 #ifdef SQLITE_HAS_CODEC 4834 /* 4835 ** Specify the key for an encrypted database. This routine should be 4836 ** called right after sqlite3_open(). 4837 ** 4838 ** The code to implement this API is not available in the public release 4839 ** of SQLite. 4840 */ 4841 SQLITE_API int SQLITE_STDCALL sqlite3_key( 4842 sqlite3 *db, /* Database to be rekeyed */ 4843 const void *pKey, int nKey /* The key */ 4844 ); 4845 SQLITE_API int SQLITE_STDCALL sqlite3_key_v2( 4846 sqlite3 *db, /* Database to be rekeyed */ 4847 const char *zDbName, /* Name of the database */ 4848 const void *pKey, int nKey /* The key */ 4849 ); 4850 4851 /* 4852 ** Change the key on an open database. If the current database is not 4853 ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the 4854 ** database is decrypted. 4855 ** 4856 ** The code to implement this API is not available in the public release 4857 ** of SQLite. 4858 */ 4859 SQLITE_API int SQLITE_STDCALL sqlite3_rekey( 4860 sqlite3 *db, /* Database to be rekeyed */ 4861 const void *pKey, int nKey /* The new key */ 4862 ); 4863 SQLITE_API int SQLITE_STDCALL sqlite3_rekey_v2( 4864 sqlite3 *db, /* Database to be rekeyed */ 4865 const char *zDbName, /* Name of the database */ 4866 const void *pKey, int nKey /* The new key */ 4867 ); 4868 4869 /* 4870 ** Specify the activation key for a SEE database. Unless 4871 ** activated, none of the SEE routines will work. 4872 */ 4873 SQLITE_API void SQLITE_STDCALL sqlite3_activate_see( 4874 const char *zPassPhrase /* Activation phrase */ 4875 ); 4876 #endif 4877 4878 #ifdef SQLITE_ENABLE_CEROD 4879 /* 4880 ** Specify the activation key for a CEROD database. Unless 4881 ** activated, none of the CEROD routines will work. 4882 */ 4883 SQLITE_API void SQLITE_STDCALL sqlite3_activate_cerod( 4884 const char *zPassPhrase /* Activation phrase */ 4885 ); 4886 #endif 4887 4888 /* 4889 ** CAPI3REF: Suspend Execution For A Short Time 4890 ** 4891 ** The sqlite3_sleep() function causes the current thread to suspend execution 4892 ** for at least a number of milliseconds specified in its parameter. 4893 ** 4894 ** If the operating system does not support sleep requests with 4895 ** millisecond time resolution, then the time will be rounded up to 4896 ** the nearest second. The number of milliseconds of sleep actually 4897 ** requested from the operating system is returned. 4898 ** 4899 ** ^SQLite implements this interface by calling the xSleep() 4900 ** method of the default [sqlite3_vfs] object. If the xSleep() method 4901 ** of the default VFS is not implemented correctly, or not implemented at 4902 ** all, then the behavior of sqlite3_sleep() may deviate from the description 4903 ** in the previous paragraphs. 4904 */ 4905 SQLITE_API int SQLITE_STDCALL sqlite3_sleep(int); 4906 4907 /* 4908 ** CAPI3REF: Name Of The Folder Holding Temporary Files 4909 ** 4910 ** ^(If this global variable is made to point to a string which is 4911 ** the name of a folder (a.k.a. directory), then all temporary files 4912 ** created by SQLite when using a built-in [sqlite3_vfs | VFS] 4913 ** will be placed in that directory.)^ ^If this variable 4914 ** is a NULL pointer, then SQLite performs a search for an appropriate 4915 ** temporary file directory. 4916 ** 4917 ** Applications are strongly discouraged from using this global variable. 4918 ** It is required to set a temporary folder on Windows Runtime (WinRT). 4919 ** But for all other platforms, it is highly recommended that applications 4920 ** neither read nor write this variable. This global variable is a relic 4921 ** that exists for backwards compatibility of legacy applications and should 4922 ** be avoided in new projects. 4923 ** 4924 ** It is not safe to read or modify this variable in more than one 4925 ** thread at a time. It is not safe to read or modify this variable 4926 ** if a [database connection] is being used at the same time in a separate 4927 ** thread. 4928 ** It is intended that this variable be set once 4929 ** as part of process initialization and before any SQLite interface 4930 ** routines have been called and that this variable remain unchanged 4931 ** thereafter. 4932 ** 4933 ** ^The [temp_store_directory pragma] may modify this variable and cause 4934 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 4935 ** the [temp_store_directory pragma] always assumes that any string 4936 ** that this variable points to is held in memory obtained from 4937 ** [sqlite3_malloc] and the pragma may attempt to free that memory 4938 ** using [sqlite3_free]. 4939 ** Hence, if this variable is modified directly, either it should be 4940 ** made NULL or made to point to memory obtained from [sqlite3_malloc] 4941 ** or else the use of the [temp_store_directory pragma] should be avoided. 4942 ** Except when requested by the [temp_store_directory pragma], SQLite 4943 ** does not free the memory that sqlite3_temp_directory points to. If 4944 ** the application wants that memory to be freed, it must do 4945 ** so itself, taking care to only do so after all [database connection] 4946 ** objects have been destroyed. 4947 ** 4948 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set 4949 ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various 4950 ** features that require the use of temporary files may fail. Here is an 4951 ** example of how to do this using C++ with the Windows Runtime: 4952 ** 4953 ** <blockquote><pre> 4954 ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> 4955 ** TemporaryFolder->Path->Data(); 4956 ** char zPathBuf[MAX_PATH + 1]; 4957 ** memset(zPathBuf, 0, sizeof(zPathBuf)); 4958 ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), 4959 ** NULL, NULL); 4960 ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); 4961 ** </pre></blockquote> 4962 */ 4963 SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; 4964 4965 /* 4966 ** CAPI3REF: Name Of The Folder Holding Database Files 4967 ** 4968 ** ^(If this global variable is made to point to a string which is 4969 ** the name of a folder (a.k.a. directory), then all database files 4970 ** specified with a relative pathname and created or accessed by 4971 ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed 4972 ** to be relative to that directory.)^ ^If this variable is a NULL 4973 ** pointer, then SQLite assumes that all database files specified 4974 ** with a relative pathname are relative to the current directory 4975 ** for the process. Only the windows VFS makes use of this global 4976 ** variable; it is ignored by the unix VFS. 4977 ** 4978 ** Changing the value of this variable while a database connection is 4979 ** open can result in a corrupt database. 4980 ** 4981 ** It is not safe to read or modify this variable in more than one 4982 ** thread at a time. It is not safe to read or modify this variable 4983 ** if a [database connection] is being used at the same time in a separate 4984 ** thread. 4985 ** It is intended that this variable be set once 4986 ** as part of process initialization and before any SQLite interface 4987 ** routines have been called and that this variable remain unchanged 4988 ** thereafter. 4989 ** 4990 ** ^The [data_store_directory pragma] may modify this variable and cause 4991 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 4992 ** the [data_store_directory pragma] always assumes that any string 4993 ** that this variable points to is held in memory obtained from 4994 ** [sqlite3_malloc] and the pragma may attempt to free that memory 4995 ** using [sqlite3_free]. 4996 ** Hence, if this variable is modified directly, either it should be 4997 ** made NULL or made to point to memory obtained from [sqlite3_malloc] 4998 ** or else the use of the [data_store_directory pragma] should be avoided. 4999 */ 5000 SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; 5001 5002 /* 5003 ** CAPI3REF: Test For Auto-Commit Mode 5004 ** KEYWORDS: {autocommit mode} 5005 ** METHOD: sqlite3 5006 ** 5007 ** ^The sqlite3_get_autocommit() interface returns non-zero or 5008 ** zero if the given database connection is or is not in autocommit mode, 5009 ** respectively. ^Autocommit mode is on by default. 5010 ** ^Autocommit mode is disabled by a [BEGIN] statement. 5011 ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. 5012 ** 5013 ** If certain kinds of errors occur on a statement within a multi-statement 5014 ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], 5015 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the 5016 ** transaction might be rolled back automatically. The only way to 5017 ** find out whether SQLite automatically rolled back the transaction after 5018 ** an error is to use this function. 5019 ** 5020 ** If another thread changes the autocommit status of the database 5021 ** connection while this routine is running, then the return value 5022 ** is undefined. 5023 */ 5024 SQLITE_API int SQLITE_STDCALL sqlite3_get_autocommit(sqlite3*); 5025 5026 /* 5027 ** CAPI3REF: Find The Database Handle Of A Prepared Statement 5028 ** METHOD: sqlite3_stmt 5029 ** 5030 ** ^The sqlite3_db_handle interface returns the [database connection] handle 5031 ** to which a [prepared statement] belongs. ^The [database connection] 5032 ** returned by sqlite3_db_handle is the same [database connection] 5033 ** that was the first argument 5034 ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to 5035 ** create the statement in the first place. 5036 */ 5037 SQLITE_API sqlite3 *SQLITE_STDCALL sqlite3_db_handle(sqlite3_stmt*); 5038 5039 /* 5040 ** CAPI3REF: Return The Filename For A Database Connection 5041 ** METHOD: sqlite3 5042 ** 5043 ** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename 5044 ** associated with database N of connection D. ^The main database file 5045 ** has the name "main". If there is no attached database N on the database 5046 ** connection D, or if database N is a temporary or in-memory database, then 5047 ** a NULL pointer is returned. 5048 ** 5049 ** ^The filename returned by this function is the output of the 5050 ** xFullPathname method of the [VFS]. ^In other words, the filename 5051 ** will be an absolute pathname, even if the filename used 5052 ** to open the database originally was a URI or relative pathname. 5053 */ 5054 SQLITE_API const char *SQLITE_STDCALL sqlite3_db_filename(sqlite3 *db, const char *zDbName); 5055 5056 /* 5057 ** CAPI3REF: Determine if a database is read-only 5058 ** METHOD: sqlite3 5059 ** 5060 ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N 5061 ** of connection D is read-only, 0 if it is read/write, or -1 if N is not 5062 ** the name of a database on connection D. 5063 */ 5064 SQLITE_API int SQLITE_STDCALL sqlite3_db_readonly(sqlite3 *db, const char *zDbName); 5065 5066 /* 5067 ** CAPI3REF: Find the next prepared statement 5068 ** METHOD: sqlite3 5069 ** 5070 ** ^This interface returns a pointer to the next [prepared statement] after 5071 ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL 5072 ** then this interface returns a pointer to the first prepared statement 5073 ** associated with the database connection pDb. ^If no prepared statement 5074 ** satisfies the conditions of this routine, it returns NULL. 5075 ** 5076 ** The [database connection] pointer D in a call to 5077 ** [sqlite3_next_stmt(D,S)] must refer to an open database 5078 ** connection and in particular must not be a NULL pointer. 5079 */ 5080 SQLITE_API sqlite3_stmt *SQLITE_STDCALL sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); 5081 5082 /* 5083 ** CAPI3REF: Commit And Rollback Notification Callbacks 5084 ** METHOD: sqlite3 5085 ** 5086 ** ^The sqlite3_commit_hook() interface registers a callback 5087 ** function to be invoked whenever a transaction is [COMMIT | committed]. 5088 ** ^Any callback set by a previous call to sqlite3_commit_hook() 5089 ** for the same database connection is overridden. 5090 ** ^The sqlite3_rollback_hook() interface registers a callback 5091 ** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. 5092 ** ^Any callback set by a previous call to sqlite3_rollback_hook() 5093 ** for the same database connection is overridden. 5094 ** ^The pArg argument is passed through to the callback. 5095 ** ^If the callback on a commit hook function returns non-zero, 5096 ** then the commit is converted into a rollback. 5097 ** 5098 ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions 5099 ** return the P argument from the previous call of the same function 5100 ** on the same [database connection] D, or NULL for 5101 ** the first call for each function on D. 5102 ** 5103 ** The commit and rollback hook callbacks are not reentrant. 5104 ** The callback implementation must not do anything that will modify 5105 ** the database connection that invoked the callback. Any actions 5106 ** to modify the database connection must be deferred until after the 5107 ** completion of the [sqlite3_step()] call that triggered the commit 5108 ** or rollback hook in the first place. 5109 ** Note that running any other SQL statements, including SELECT statements, 5110 ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify 5111 ** the database connections for the meaning of "modify" in this paragraph. 5112 ** 5113 ** ^Registering a NULL function disables the callback. 5114 ** 5115 ** ^When the commit hook callback routine returns zero, the [COMMIT] 5116 ** operation is allowed to continue normally. ^If the commit hook 5117 ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. 5118 ** ^The rollback hook is invoked on a rollback that results from a commit 5119 ** hook returning non-zero, just as it would be with any other rollback. 5120 ** 5121 ** ^For the purposes of this API, a transaction is said to have been 5122 ** rolled back if an explicit "ROLLBACK" statement is executed, or 5123 ** an error or constraint causes an implicit rollback to occur. 5124 ** ^The rollback callback is not invoked if a transaction is 5125 ** automatically rolled back because the database connection is closed. 5126 ** 5127 ** See also the [sqlite3_update_hook()] interface. 5128 */ 5129 SQLITE_API void *SQLITE_STDCALL sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); 5130 SQLITE_API void *SQLITE_STDCALL sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); 5131 5132 /* 5133 ** CAPI3REF: Data Change Notification Callbacks 5134 ** METHOD: sqlite3 5135 ** 5136 ** ^The sqlite3_update_hook() interface registers a callback function 5137 ** with the [database connection] identified by the first argument 5138 ** to be invoked whenever a row is updated, inserted or deleted in 5139 ** a rowid table. 5140 ** ^Any callback set by a previous call to this function 5141 ** for the same database connection is overridden. 5142 ** 5143 ** ^The second argument is a pointer to the function to invoke when a 5144 ** row is updated, inserted or deleted in a rowid table. 5145 ** ^The first argument to the callback is a copy of the third argument 5146 ** to sqlite3_update_hook(). 5147 ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], 5148 ** or [SQLITE_UPDATE], depending on the operation that caused the callback 5149 ** to be invoked. 5150 ** ^The third and fourth arguments to the callback contain pointers to the 5151 ** database and table name containing the affected row. 5152 ** ^The final callback parameter is the [rowid] of the row. 5153 ** ^In the case of an update, this is the [rowid] after the update takes place. 5154 ** 5155 ** ^(The update hook is not invoked when internal system tables are 5156 ** modified (i.e. sqlite_master and sqlite_sequence).)^ 5157 ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. 5158 ** 5159 ** ^In the current implementation, the update hook 5160 ** is not invoked when duplication rows are deleted because of an 5161 ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook 5162 ** invoked when rows are deleted using the [truncate optimization]. 5163 ** The exceptions defined in this paragraph might change in a future 5164 ** release of SQLite. 5165 ** 5166 ** The update hook implementation must not do anything that will modify 5167 ** the database connection that invoked the update hook. Any actions 5168 ** to modify the database connection must be deferred until after the 5169 ** completion of the [sqlite3_step()] call that triggered the update hook. 5170 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 5171 ** database connections for the meaning of "modify" in this paragraph. 5172 ** 5173 ** ^The sqlite3_update_hook(D,C,P) function 5174 ** returns the P argument from the previous call 5175 ** on the same [database connection] D, or NULL for 5176 ** the first call on D. 5177 ** 5178 ** See also the [sqlite3_commit_hook()] and [sqlite3_rollback_hook()] 5179 ** interfaces. 5180 */ 5181 SQLITE_API void *SQLITE_STDCALL sqlite3_update_hook( 5182 sqlite3*, 5183 void(*)(void *,int ,char const *,char const *,sqlite3_int64), 5184 void* 5185 ); 5186 5187 /* 5188 ** CAPI3REF: Enable Or Disable Shared Pager Cache 5189 ** 5190 ** ^(This routine enables or disables the sharing of the database cache 5191 ** and schema data structures between [database connection | connections] 5192 ** to the same database. Sharing is enabled if the argument is true 5193 ** and disabled if the argument is false.)^ 5194 ** 5195 ** ^Cache sharing is enabled and disabled for an entire process. 5196 ** This is a change as of SQLite version 3.5.0. In prior versions of SQLite, 5197 ** sharing was enabled or disabled for each thread separately. 5198 ** 5199 ** ^(The cache sharing mode set by this interface effects all subsequent 5200 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. 5201 ** Existing database connections continue use the sharing mode 5202 ** that was in effect at the time they were opened.)^ 5203 ** 5204 ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled 5205 ** successfully. An [error code] is returned otherwise.)^ 5206 ** 5207 ** ^Shared cache is disabled by default. But this might change in 5208 ** future releases of SQLite. Applications that care about shared 5209 ** cache setting should set it explicitly. 5210 ** 5211 ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 5212 ** and will always return SQLITE_MISUSE. On those systems, 5213 ** shared cache mode should be enabled per-database connection via 5214 ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. 5215 ** 5216 ** This interface is threadsafe on processors where writing a 5217 ** 32-bit integer is atomic. 5218 ** 5219 ** See Also: [SQLite Shared-Cache Mode] 5220 */ 5221 SQLITE_API int SQLITE_STDCALL sqlite3_enable_shared_cache(int); 5222 5223 /* 5224 ** CAPI3REF: Attempt To Free Heap Memory 5225 ** 5226 ** ^The sqlite3_release_memory() interface attempts to free N bytes 5227 ** of heap memory by deallocating non-essential memory allocations 5228 ** held by the database library. Memory used to cache database 5229 ** pages to improve performance is an example of non-essential memory. 5230 ** ^sqlite3_release_memory() returns the number of bytes actually freed, 5231 ** which might be more or less than the amount requested. 5232 ** ^The sqlite3_release_memory() routine is a no-op returning zero 5233 ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. 5234 ** 5235 ** See also: [sqlite3_db_release_memory()] 5236 */ 5237 SQLITE_API int SQLITE_STDCALL sqlite3_release_memory(int); 5238 5239 /* 5240 ** CAPI3REF: Free Memory Used By A Database Connection 5241 ** METHOD: sqlite3 5242 ** 5243 ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap 5244 ** memory as possible from database connection D. Unlike the 5245 ** [sqlite3_release_memory()] interface, this interface is in effect even 5246 ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is 5247 ** omitted. 5248 ** 5249 ** See also: [sqlite3_release_memory()] 5250 */ 5251 SQLITE_API int SQLITE_STDCALL sqlite3_db_release_memory(sqlite3*); 5252 5253 /* 5254 ** CAPI3REF: Impose A Limit On Heap Size 5255 ** 5256 ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the 5257 ** soft limit on the amount of heap memory that may be allocated by SQLite. 5258 ** ^SQLite strives to keep heap memory utilization below the soft heap 5259 ** limit by reducing the number of pages held in the page cache 5260 ** as heap memory usages approaches the limit. 5261 ** ^The soft heap limit is "soft" because even though SQLite strives to stay 5262 ** below the limit, it will exceed the limit rather than generate 5263 ** an [SQLITE_NOMEM] error. In other words, the soft heap limit 5264 ** is advisory only. 5265 ** 5266 ** ^The return value from sqlite3_soft_heap_limit64() is the size of 5267 ** the soft heap limit prior to the call, or negative in the case of an 5268 ** error. ^If the argument N is negative 5269 ** then no change is made to the soft heap limit. Hence, the current 5270 ** size of the soft heap limit can be determined by invoking 5271 ** sqlite3_soft_heap_limit64() with a negative argument. 5272 ** 5273 ** ^If the argument N is zero then the soft heap limit is disabled. 5274 ** 5275 ** ^(The soft heap limit is not enforced in the current implementation 5276 ** if one or more of following conditions are true: 5277 ** 5278 ** <ul> 5279 ** <li> The soft heap limit is set to zero. 5280 ** <li> Memory accounting is disabled using a combination of the 5281 ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and 5282 ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. 5283 ** <li> An alternative page cache implementation is specified using 5284 ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). 5285 ** <li> The page cache allocates from its own memory pool supplied 5286 ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than 5287 ** from the heap. 5288 ** </ul>)^ 5289 ** 5290 ** Beginning with SQLite version 3.7.3, the soft heap limit is enforced 5291 ** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT] 5292 ** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT], 5293 ** the soft heap limit is enforced on every memory allocation. Without 5294 ** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced 5295 ** when memory is allocated by the page cache. Testing suggests that because 5296 ** the page cache is the predominate memory user in SQLite, most 5297 ** applications will achieve adequate soft heap limit enforcement without 5298 ** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT]. 5299 ** 5300 ** The circumstances under which SQLite will enforce the soft heap limit may 5301 ** changes in future releases of SQLite. 5302 */ 5303 SQLITE_API sqlite3_int64 SQLITE_STDCALL sqlite3_soft_heap_limit64(sqlite3_int64 N); 5304 5305 /* 5306 ** CAPI3REF: Deprecated Soft Heap Limit Interface 5307 ** DEPRECATED 5308 ** 5309 ** This is a deprecated version of the [sqlite3_soft_heap_limit64()] 5310 ** interface. This routine is provided for historical compatibility 5311 ** only. All new applications should use the 5312 ** [sqlite3_soft_heap_limit64()] interface rather than this one. 5313 */ 5314 SQLITE_API SQLITE_DEPRECATED void SQLITE_STDCALL sqlite3_soft_heap_limit(int N); 5315 5316 5317 /* 5318 ** CAPI3REF: Extract Metadata About A Column Of A Table 5319 ** METHOD: sqlite3 5320 ** 5321 ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns 5322 ** information about column C of table T in database D 5323 ** on [database connection] X.)^ ^The sqlite3_table_column_metadata() 5324 ** interface returns SQLITE_OK and fills in the non-NULL pointers in 5325 ** the final five arguments with appropriate values if the specified 5326 ** column exists. ^The sqlite3_table_column_metadata() interface returns 5327 ** SQLITE_ERROR and if the specified column does not exist. 5328 ** ^If the column-name parameter to sqlite3_table_column_metadata() is a 5329 ** NULL pointer, then this routine simply checks for the existance of the 5330 ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it 5331 ** does not. 5332 ** 5333 ** ^The column is identified by the second, third and fourth parameters to 5334 ** this function. ^(The second parameter is either the name of the database 5335 ** (i.e. "main", "temp", or an attached database) containing the specified 5336 ** table or NULL.)^ ^If it is NULL, then all attached databases are searched 5337 ** for the table using the same algorithm used by the database engine to 5338 ** resolve unqualified table references. 5339 ** 5340 ** ^The third and fourth parameters to this function are the table and column 5341 ** name of the desired column, respectively. 5342 ** 5343 ** ^Metadata is returned by writing to the memory locations passed as the 5th 5344 ** and subsequent parameters to this function. ^Any of these arguments may be 5345 ** NULL, in which case the corresponding element of metadata is omitted. 5346 ** 5347 ** ^(<blockquote> 5348 ** <table border="1"> 5349 ** <tr><th> Parameter <th> Output<br>Type <th> Description 5350 ** 5351 ** <tr><td> 5th <td> const char* <td> Data type 5352 ** <tr><td> 6th <td> const char* <td> Name of default collation sequence 5353 ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint 5354 ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY 5355 ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] 5356 ** </table> 5357 ** </blockquote>)^ 5358 ** 5359 ** ^The memory pointed to by the character pointers returned for the 5360 ** declaration type and collation sequence is valid until the next 5361 ** call to any SQLite API function. 5362 ** 5363 ** ^If the specified table is actually a view, an [error code] is returned. 5364 ** 5365 ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table 5366 ** is not a [WITHOUT ROWID] table and an 5367 ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output 5368 ** parameters are set for the explicitly declared column. ^(If there is no 5369 ** [INTEGER PRIMARY KEY] column, then the outputs 5370 ** for the [rowid] are set as follows: 5371 ** 5372 ** <pre> 5373 ** data type: "INTEGER" 5374 ** collation sequence: "BINARY" 5375 ** not null: 0 5376 ** primary key: 1 5377 ** auto increment: 0 5378 ** </pre>)^ 5379 ** 5380 ** ^This function causes all database schemas to be read from disk and 5381 ** parsed, if that has not already been done, and returns an error if 5382 ** any errors are encountered while loading the schema. 5383 */ 5384 SQLITE_API int SQLITE_STDCALL sqlite3_table_column_metadata( 5385 sqlite3 *db, /* Connection handle */ 5386 const char *zDbName, /* Database name or NULL */ 5387 const char *zTableName, /* Table name */ 5388 const char *zColumnName, /* Column name */ 5389 char const **pzDataType, /* OUTPUT: Declared data type */ 5390 char const **pzCollSeq, /* OUTPUT: Collation sequence name */ 5391 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ 5392 int *pPrimaryKey, /* OUTPUT: True if column part of PK */ 5393 int *pAutoinc /* OUTPUT: True if column is auto-increment */ 5394 ); 5395 5396 /* 5397 ** CAPI3REF: Load An Extension 5398 ** METHOD: sqlite3 5399 ** 5400 ** ^This interface loads an SQLite extension library from the named file. 5401 ** 5402 ** ^The sqlite3_load_extension() interface attempts to load an 5403 ** [SQLite extension] library contained in the file zFile. If 5404 ** the file cannot be loaded directly, attempts are made to load 5405 ** with various operating-system specific extensions added. 5406 ** So for example, if "samplelib" cannot be loaded, then names like 5407 ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might 5408 ** be tried also. 5409 ** 5410 ** ^The entry point is zProc. 5411 ** ^(zProc may be 0, in which case SQLite will try to come up with an 5412 ** entry point name on its own. It first tries "sqlite3_extension_init". 5413 ** If that does not work, it constructs a name "sqlite3_X_init" where the 5414 ** X is consists of the lower-case equivalent of all ASCII alphabetic 5415 ** characters in the filename from the last "/" to the first following 5416 ** "." and omitting any initial "lib".)^ 5417 ** ^The sqlite3_load_extension() interface returns 5418 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. 5419 ** ^If an error occurs and pzErrMsg is not 0, then the 5420 ** [sqlite3_load_extension()] interface shall attempt to 5421 ** fill *pzErrMsg with error message text stored in memory 5422 ** obtained from [sqlite3_malloc()]. The calling function 5423 ** should free this memory by calling [sqlite3_free()]. 5424 ** 5425 ** ^Extension loading must be enabled using 5426 ** [sqlite3_enable_load_extension()] prior to calling this API, 5427 ** otherwise an error will be returned. 5428 ** 5429 ** See also the [load_extension() SQL function]. 5430 */ 5431 SQLITE_API int SQLITE_STDCALL sqlite3_load_extension( 5432 sqlite3 *db, /* Load the extension into this database connection */ 5433 const char *zFile, /* Name of the shared library containing extension */ 5434 const char *zProc, /* Entry point. Derived from zFile if 0 */ 5435 char **pzErrMsg /* Put error message here if not 0 */ 5436 ); 5437 5438 /* 5439 ** CAPI3REF: Enable Or Disable Extension Loading 5440 ** METHOD: sqlite3 5441 ** 5442 ** ^So as not to open security holes in older applications that are 5443 ** unprepared to deal with [extension loading], and as a means of disabling 5444 ** [extension loading] while evaluating user-entered SQL, the following API 5445 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off. 5446 ** 5447 ** ^Extension loading is off by default. 5448 ** ^Call the sqlite3_enable_load_extension() routine with onoff==1 5449 ** to turn extension loading on and call it with onoff==0 to turn 5450 ** it back off again. 5451 */ 5452 SQLITE_API int SQLITE_STDCALL sqlite3_enable_load_extension(sqlite3 *db, int onoff); 5453 5454 /* 5455 ** CAPI3REF: Automatically Load Statically Linked Extensions 5456 ** 5457 ** ^This interface causes the xEntryPoint() function to be invoked for 5458 ** each new [database connection] that is created. The idea here is that 5459 ** xEntryPoint() is the entry point for a statically linked [SQLite extension] 5460 ** that is to be automatically loaded into all new database connections. 5461 ** 5462 ** ^(Even though the function prototype shows that xEntryPoint() takes 5463 ** no arguments and returns void, SQLite invokes xEntryPoint() with three 5464 ** arguments and expects and integer result as if the signature of the 5465 ** entry point where as follows: 5466 ** 5467 ** <blockquote><pre> 5468 ** int xEntryPoint( 5469 ** sqlite3 *db, 5470 ** const char **pzErrMsg, 5471 ** const struct sqlite3_api_routines *pThunk 5472 ** ); 5473 ** </pre></blockquote>)^ 5474 ** 5475 ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg 5476 ** point to an appropriate error message (obtained from [sqlite3_mprintf()]) 5477 ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg 5478 ** is NULL before calling the xEntryPoint(). ^SQLite will invoke 5479 ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any 5480 ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], 5481 ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. 5482 ** 5483 ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already 5484 ** on the list of automatic extensions is a harmless no-op. ^No entry point 5485 ** will be called more than once for each database connection that is opened. 5486 ** 5487 ** See also: [sqlite3_reset_auto_extension()] 5488 ** and [sqlite3_cancel_auto_extension()] 5489 */ 5490 SQLITE_API int SQLITE_STDCALL sqlite3_auto_extension(void (*xEntryPoint)(void)); 5491 5492 /* 5493 ** CAPI3REF: Cancel Automatic Extension Loading 5494 ** 5495 ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the 5496 ** initialization routine X that was registered using a prior call to 5497 ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] 5498 ** routine returns 1 if initialization routine X was successfully 5499 ** unregistered and it returns 0 if X was not on the list of initialization 5500 ** routines. 5501 */ 5502 SQLITE_API int SQLITE_STDCALL sqlite3_cancel_auto_extension(void (*xEntryPoint)(void)); 5503 5504 /* 5505 ** CAPI3REF: Reset Automatic Extension Loading 5506 ** 5507 ** ^This interface disables all automatic extensions previously 5508 ** registered using [sqlite3_auto_extension()]. 5509 */ 5510 SQLITE_API void SQLITE_STDCALL sqlite3_reset_auto_extension(void); 5511 5512 /* 5513 ** The interface to the virtual-table mechanism is currently considered 5514 ** to be experimental. The interface might change in incompatible ways. 5515 ** If this is a problem for you, do not use the interface at this time. 5516 ** 5517 ** When the virtual-table mechanism stabilizes, we will declare the 5518 ** interface fixed, support it indefinitely, and remove this comment. 5519 */ 5520 5521 /* 5522 ** Structures used by the virtual table interface 5523 */ 5524 typedef struct sqlite3_vtab sqlite3_vtab; 5525 typedef struct sqlite3_index_info sqlite3_index_info; 5526 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; 5527 typedef struct sqlite3_module sqlite3_module; 5528 5529 /* 5530 ** CAPI3REF: Virtual Table Object 5531 ** KEYWORDS: sqlite3_module {virtual table module} 5532 ** 5533 ** This structure, sometimes called a "virtual table module", 5534 ** defines the implementation of a [virtual tables]. 5535 ** This structure consists mostly of methods for the module. 5536 ** 5537 ** ^A virtual table module is created by filling in a persistent 5538 ** instance of this structure and passing a pointer to that instance 5539 ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. 5540 ** ^The registration remains valid until it is replaced by a different 5541 ** module or until the [database connection] closes. The content 5542 ** of this structure must not change while it is registered with 5543 ** any database connection. 5544 */ 5545 struct sqlite3_module { 5546 int iVersion; 5547 int (*xCreate)(sqlite3*, void *pAux, 5548 int argc, const char *const*argv, 5549 sqlite3_vtab **ppVTab, char**); 5550 int (*xConnect)(sqlite3*, void *pAux, 5551 int argc, const char *const*argv, 5552 sqlite3_vtab **ppVTab, char**); 5553 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); 5554 int (*xDisconnect)(sqlite3_vtab *pVTab); 5555 int (*xDestroy)(sqlite3_vtab *pVTab); 5556 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); 5557 int (*xClose)(sqlite3_vtab_cursor*); 5558 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, 5559 int argc, sqlite3_value **argv); 5560 int (*xNext)(sqlite3_vtab_cursor*); 5561 int (*xEof)(sqlite3_vtab_cursor*); 5562 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); 5563 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); 5564 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); 5565 int (*xBegin)(sqlite3_vtab *pVTab); 5566 int (*xSync)(sqlite3_vtab *pVTab); 5567 int (*xCommit)(sqlite3_vtab *pVTab); 5568 int (*xRollback)(sqlite3_vtab *pVTab); 5569 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, 5570 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), 5571 void **ppArg); 5572 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); 5573 /* The methods above are in version 1 of the sqlite_module object. Those 5574 ** below are for version 2 and greater. */ 5575 int (*xSavepoint)(sqlite3_vtab *pVTab, int); 5576 int (*xRelease)(sqlite3_vtab *pVTab, int); 5577 int (*xRollbackTo)(sqlite3_vtab *pVTab, int); 5578 }; 5579 5580 /* 5581 ** CAPI3REF: Virtual Table Indexing Information 5582 ** KEYWORDS: sqlite3_index_info 5583 ** 5584 ** The sqlite3_index_info structure and its substructures is used as part 5585 ** of the [virtual table] interface to 5586 ** pass information into and receive the reply from the [xBestIndex] 5587 ** method of a [virtual table module]. The fields under **Inputs** are the 5588 ** inputs to xBestIndex and are read-only. xBestIndex inserts its 5589 ** results into the **Outputs** fields. 5590 ** 5591 ** ^(The aConstraint[] array records WHERE clause constraints of the form: 5592 ** 5593 ** <blockquote>column OP expr</blockquote> 5594 ** 5595 ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is 5596 ** stored in aConstraint[].op using one of the 5597 ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ 5598 ** ^(The index of the column is stored in 5599 ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the 5600 ** expr on the right-hand side can be evaluated (and thus the constraint 5601 ** is usable) and false if it cannot.)^ 5602 ** 5603 ** ^The optimizer automatically inverts terms of the form "expr OP column" 5604 ** and makes other simplifications to the WHERE clause in an attempt to 5605 ** get as many WHERE clause terms into the form shown above as possible. 5606 ** ^The aConstraint[] array only reports WHERE clause terms that are 5607 ** relevant to the particular virtual table being queried. 5608 ** 5609 ** ^Information about the ORDER BY clause is stored in aOrderBy[]. 5610 ** ^Each term of aOrderBy records a column of the ORDER BY clause. 5611 ** 5612 ** The [xBestIndex] method must fill aConstraintUsage[] with information 5613 ** about what parameters to pass to xFilter. ^If argvIndex>0 then 5614 ** the right-hand side of the corresponding aConstraint[] is evaluated 5615 ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit 5616 ** is true, then the constraint is assumed to be fully handled by the 5617 ** virtual table and is not checked again by SQLite.)^ 5618 ** 5619 ** ^The idxNum and idxPtr values are recorded and passed into the 5620 ** [xFilter] method. 5621 ** ^[sqlite3_free()] is used to free idxPtr if and only if 5622 ** needToFreeIdxPtr is true. 5623 ** 5624 ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in 5625 ** the correct order to satisfy the ORDER BY clause so that no separate 5626 ** sorting step is required. 5627 ** 5628 ** ^The estimatedCost value is an estimate of the cost of a particular 5629 ** strategy. A cost of N indicates that the cost of the strategy is similar 5630 ** to a linear scan of an SQLite table with N rows. A cost of log(N) 5631 ** indicates that the expense of the operation is similar to that of a 5632 ** binary search on a unique indexed field of an SQLite table with N rows. 5633 ** 5634 ** ^The estimatedRows value is an estimate of the number of rows that 5635 ** will be returned by the strategy. 5636 ** 5637 ** The xBestIndex method may optionally populate the idxFlags field with a 5638 ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - 5639 ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite 5640 ** assumes that the strategy may visit at most one row. 5641 ** 5642 ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then 5643 ** SQLite also assumes that if a call to the xUpdate() method is made as 5644 ** part of the same statement to delete or update a virtual table row and the 5645 ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback 5646 ** any database changes. In other words, if the xUpdate() returns 5647 ** SQLITE_CONSTRAINT, the database contents must be exactly as they were 5648 ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not 5649 ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by 5650 ** the xUpdate method are automatically rolled back by SQLite. 5651 ** 5652 ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info 5653 ** structure for SQLite version 3.8.2. If a virtual table extension is 5654 ** used with an SQLite version earlier than 3.8.2, the results of attempting 5655 ** to read or write the estimatedRows field are undefined (but are likely 5656 ** to included crashing the application). The estimatedRows field should 5657 ** therefore only be used if [sqlite3_libversion_number()] returns a 5658 ** value greater than or equal to 3008002. Similarly, the idxFlags field 5659 ** was added for version 3.9.0. It may therefore only be used if 5660 ** sqlite3_libversion_number() returns a value greater than or equal to 5661 ** 3009000. 5662 */ 5663 struct sqlite3_index_info { 5664 /* Inputs */ 5665 int nConstraint; /* Number of entries in aConstraint */ 5666 struct sqlite3_index_constraint { 5667 int iColumn; /* Column on left-hand side of constraint */ 5668 unsigned char op; /* Constraint operator */ 5669 unsigned char usable; /* True if this constraint is usable */ 5670 int iTermOffset; /* Used internally - xBestIndex should ignore */ 5671 } *aConstraint; /* Table of WHERE clause constraints */ 5672 int nOrderBy; /* Number of terms in the ORDER BY clause */ 5673 struct sqlite3_index_orderby { 5674 int iColumn; /* Column number */ 5675 unsigned char desc; /* True for DESC. False for ASC. */ 5676 } *aOrderBy; /* The ORDER BY clause */ 5677 /* Outputs */ 5678 struct sqlite3_index_constraint_usage { 5679 int argvIndex; /* if >0, constraint is part of argv to xFilter */ 5680 unsigned char omit; /* Do not code a test for this constraint */ 5681 } *aConstraintUsage; 5682 int idxNum; /* Number used to identify the index */ 5683 char *idxStr; /* String, possibly obtained from sqlite3_malloc */ 5684 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ 5685 int orderByConsumed; /* True if output is already ordered */ 5686 double estimatedCost; /* Estimated cost of using this index */ 5687 /* Fields below are only available in SQLite 3.8.2 and later */ 5688 sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ 5689 /* Fields below are only available in SQLite 3.9.0 and later */ 5690 int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ 5691 }; 5692 5693 /* 5694 ** CAPI3REF: Virtual Table Scan Flags 5695 */ 5696 #define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ 5697 5698 /* 5699 ** CAPI3REF: Virtual Table Constraint Operator Codes 5700 ** 5701 ** These macros defined the allowed values for the 5702 ** [sqlite3_index_info].aConstraint[].op field. Each value represents 5703 ** an operator that is part of a constraint term in the wHERE clause of 5704 ** a query that uses a [virtual table]. 5705 */ 5706 #define SQLITE_INDEX_CONSTRAINT_EQ 2 5707 #define SQLITE_INDEX_CONSTRAINT_GT 4 5708 #define SQLITE_INDEX_CONSTRAINT_LE 8 5709 #define SQLITE_INDEX_CONSTRAINT_LT 16 5710 #define SQLITE_INDEX_CONSTRAINT_GE 32 5711 #define SQLITE_INDEX_CONSTRAINT_MATCH 64 5712 5713 /* 5714 ** CAPI3REF: Register A Virtual Table Implementation 5715 ** METHOD: sqlite3 5716 ** 5717 ** ^These routines are used to register a new [virtual table module] name. 5718 ** ^Module names must be registered before 5719 ** creating a new [virtual table] using the module and before using a 5720 ** preexisting [virtual table] for the module. 5721 ** 5722 ** ^The module name is registered on the [database connection] specified 5723 ** by the first parameter. ^The name of the module is given by the 5724 ** second parameter. ^The third parameter is a pointer to 5725 ** the implementation of the [virtual table module]. ^The fourth 5726 ** parameter is an arbitrary client data pointer that is passed through 5727 ** into the [xCreate] and [xConnect] methods of the virtual table module 5728 ** when a new virtual table is be being created or reinitialized. 5729 ** 5730 ** ^The sqlite3_create_module_v2() interface has a fifth parameter which 5731 ** is a pointer to a destructor for the pClientData. ^SQLite will 5732 ** invoke the destructor function (if it is not NULL) when SQLite 5733 ** no longer needs the pClientData pointer. ^The destructor will also 5734 ** be invoked if the call to sqlite3_create_module_v2() fails. 5735 ** ^The sqlite3_create_module() 5736 ** interface is equivalent to sqlite3_create_module_v2() with a NULL 5737 ** destructor. 5738 */ 5739 SQLITE_API int SQLITE_STDCALL sqlite3_create_module( 5740 sqlite3 *db, /* SQLite connection to register module with */ 5741 const char *zName, /* Name of the module */ 5742 const sqlite3_module *p, /* Methods for the module */ 5743 void *pClientData /* Client data for xCreate/xConnect */ 5744 ); 5745 SQLITE_API int SQLITE_STDCALL sqlite3_create_module_v2( 5746 sqlite3 *db, /* SQLite connection to register module with */ 5747 const char *zName, /* Name of the module */ 5748 const sqlite3_module *p, /* Methods for the module */ 5749 void *pClientData, /* Client data for xCreate/xConnect */ 5750 void(*xDestroy)(void*) /* Module destructor function */ 5751 ); 5752 5753 /* 5754 ** CAPI3REF: Virtual Table Instance Object 5755 ** KEYWORDS: sqlite3_vtab 5756 ** 5757 ** Every [virtual table module] implementation uses a subclass 5758 ** of this object to describe a particular instance 5759 ** of the [virtual table]. Each subclass will 5760 ** be tailored to the specific needs of the module implementation. 5761 ** The purpose of this superclass is to define certain fields that are 5762 ** common to all module implementations. 5763 ** 5764 ** ^Virtual tables methods can set an error message by assigning a 5765 ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should 5766 ** take care that any prior string is freed by a call to [sqlite3_free()] 5767 ** prior to assigning a new string to zErrMsg. ^After the error message 5768 ** is delivered up to the client application, the string will be automatically 5769 ** freed by sqlite3_free() and the zErrMsg field will be zeroed. 5770 */ 5771 struct sqlite3_vtab { 5772 const sqlite3_module *pModule; /* The module for this virtual table */ 5773 int nRef; /* Number of open cursors */ 5774 char *zErrMsg; /* Error message from sqlite3_mprintf() */ 5775 /* Virtual table implementations will typically add additional fields */ 5776 }; 5777 5778 /* 5779 ** CAPI3REF: Virtual Table Cursor Object 5780 ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} 5781 ** 5782 ** Every [virtual table module] implementation uses a subclass of the 5783 ** following structure to describe cursors that point into the 5784 ** [virtual table] and are used 5785 ** to loop through the virtual table. Cursors are created using the 5786 ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed 5787 ** by the [sqlite3_module.xClose | xClose] method. Cursors are used 5788 ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods 5789 ** of the module. Each module implementation will define 5790 ** the content of a cursor structure to suit its own needs. 5791 ** 5792 ** This superclass exists in order to define fields of the cursor that 5793 ** are common to all implementations. 5794 */ 5795 struct sqlite3_vtab_cursor { 5796 sqlite3_vtab *pVtab; /* Virtual table of this cursor */ 5797 /* Virtual table implementations will typically add additional fields */ 5798 }; 5799 5800 /* 5801 ** CAPI3REF: Declare The Schema Of A Virtual Table 5802 ** 5803 ** ^The [xCreate] and [xConnect] methods of a 5804 ** [virtual table module] call this interface 5805 ** to declare the format (the names and datatypes of the columns) of 5806 ** the virtual tables they implement. 5807 */ 5808 SQLITE_API int SQLITE_STDCALL sqlite3_declare_vtab(sqlite3*, const char *zSQL); 5809 5810 /* 5811 ** CAPI3REF: Overload A Function For A Virtual Table 5812 ** METHOD: sqlite3 5813 ** 5814 ** ^(Virtual tables can provide alternative implementations of functions 5815 ** using the [xFindFunction] method of the [virtual table module]. 5816 ** But global versions of those functions 5817 ** must exist in order to be overloaded.)^ 5818 ** 5819 ** ^(This API makes sure a global version of a function with a particular 5820 ** name and number of parameters exists. If no such function exists 5821 ** before this API is called, a new function is created.)^ ^The implementation 5822 ** of the new function always causes an exception to be thrown. So 5823 ** the new function is not good for anything by itself. Its only 5824 ** purpose is to be a placeholder function that can be overloaded 5825 ** by a [virtual table]. 5826 */ 5827 SQLITE_API int SQLITE_STDCALL sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); 5828 5829 /* 5830 ** The interface to the virtual-table mechanism defined above (back up 5831 ** to a comment remarkably similar to this one) is currently considered 5832 ** to be experimental. The interface might change in incompatible ways. 5833 ** If this is a problem for you, do not use the interface at this time. 5834 ** 5835 ** When the virtual-table mechanism stabilizes, we will declare the 5836 ** interface fixed, support it indefinitely, and remove this comment. 5837 */ 5838 5839 /* 5840 ** CAPI3REF: A Handle To An Open BLOB 5841 ** KEYWORDS: {BLOB handle} {BLOB handles} 5842 ** 5843 ** An instance of this object represents an open BLOB on which 5844 ** [sqlite3_blob_open | incremental BLOB I/O] can be performed. 5845 ** ^Objects of this type are created by [sqlite3_blob_open()] 5846 ** and destroyed by [sqlite3_blob_close()]. 5847 ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces 5848 ** can be used to read or write small subsections of the BLOB. 5849 ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. 5850 */ 5851 typedef struct sqlite3_blob sqlite3_blob; 5852 5853 /* 5854 ** CAPI3REF: Open A BLOB For Incremental I/O 5855 ** METHOD: sqlite3 5856 ** CONSTRUCTOR: sqlite3_blob 5857 ** 5858 ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located 5859 ** in row iRow, column zColumn, table zTable in database zDb; 5860 ** in other words, the same BLOB that would be selected by: 5861 ** 5862 ** <pre> 5863 ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; 5864 ** </pre>)^ 5865 ** 5866 ** ^(Parameter zDb is not the filename that contains the database, but 5867 ** rather the symbolic name of the database. For attached databases, this is 5868 ** the name that appears after the AS keyword in the [ATTACH] statement. 5869 ** For the main database file, the database name is "main". For TEMP 5870 ** tables, the database name is "temp".)^ 5871 ** 5872 ** ^If the flags parameter is non-zero, then the BLOB is opened for read 5873 ** and write access. ^If the flags parameter is zero, the BLOB is opened for 5874 ** read-only access. 5875 ** 5876 ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored 5877 ** in *ppBlob. Otherwise an [error code] is returned and, unless the error 5878 ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided 5879 ** the API is not misused, it is always safe to call [sqlite3_blob_close()] 5880 ** on *ppBlob after this function it returns. 5881 ** 5882 ** This function fails with SQLITE_ERROR if any of the following are true: 5883 ** <ul> 5884 ** <li> ^(Database zDb does not exist)^, 5885 ** <li> ^(Table zTable does not exist within database zDb)^, 5886 ** <li> ^(Table zTable is a WITHOUT ROWID table)^, 5887 ** <li> ^(Column zColumn does not exist)^, 5888 ** <li> ^(Row iRow is not present in the table)^, 5889 ** <li> ^(The specified column of row iRow contains a value that is not 5890 ** a TEXT or BLOB value)^, 5891 ** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE 5892 ** constraint and the blob is being opened for read/write access)^, 5893 ** <li> ^([foreign key constraints | Foreign key constraints] are enabled, 5894 ** column zColumn is part of a [child key] definition and the blob is 5895 ** being opened for read/write access)^. 5896 ** </ul> 5897 ** 5898 ** ^Unless it returns SQLITE_MISUSE, this function sets the 5899 ** [database connection] error code and message accessible via 5900 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 5901 ** 5902 ** 5903 ** ^(If the row that a BLOB handle points to is modified by an 5904 ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects 5905 ** then the BLOB handle is marked as "expired". 5906 ** This is true if any column of the row is changed, even a column 5907 ** other than the one the BLOB handle is open on.)^ 5908 ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for 5909 ** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. 5910 ** ^(Changes written into a BLOB prior to the BLOB expiring are not 5911 ** rolled back by the expiration of the BLOB. Such changes will eventually 5912 ** commit if the transaction continues to completion.)^ 5913 ** 5914 ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of 5915 ** the opened blob. ^The size of a blob may not be changed by this 5916 ** interface. Use the [UPDATE] SQL command to change the size of a 5917 ** blob. 5918 ** 5919 ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces 5920 ** and the built-in [zeroblob] SQL function may be used to create a 5921 ** zero-filled blob to read or write using the incremental-blob interface. 5922 ** 5923 ** To avoid a resource leak, every open [BLOB handle] should eventually 5924 ** be released by a call to [sqlite3_blob_close()]. 5925 */ 5926 SQLITE_API int SQLITE_STDCALL sqlite3_blob_open( 5927 sqlite3*, 5928 const char *zDb, 5929 const char *zTable, 5930 const char *zColumn, 5931 sqlite3_int64 iRow, 5932 int flags, 5933 sqlite3_blob **ppBlob 5934 ); 5935 5936 /* 5937 ** CAPI3REF: Move a BLOB Handle to a New Row 5938 ** METHOD: sqlite3_blob 5939 ** 5940 ** ^This function is used to move an existing blob handle so that it points 5941 ** to a different row of the same database table. ^The new row is identified 5942 ** by the rowid value passed as the second argument. Only the row can be 5943 ** changed. ^The database, table and column on which the blob handle is open 5944 ** remain the same. Moving an existing blob handle to a new row can be 5945 ** faster than closing the existing handle and opening a new one. 5946 ** 5947 ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - 5948 ** it must exist and there must be either a blob or text value stored in 5949 ** the nominated column.)^ ^If the new row is not present in the table, or if 5950 ** it does not contain a blob or text value, or if another error occurs, an 5951 ** SQLite error code is returned and the blob handle is considered aborted. 5952 ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or 5953 ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return 5954 ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle 5955 ** always returns zero. 5956 ** 5957 ** ^This function sets the database handle error code and message. 5958 */ 5959 SQLITE_API int SQLITE_STDCALL sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); 5960 5961 /* 5962 ** CAPI3REF: Close A BLOB Handle 5963 ** DESTRUCTOR: sqlite3_blob 5964 ** 5965 ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed 5966 ** unconditionally. Even if this routine returns an error code, the 5967 ** handle is still closed.)^ 5968 ** 5969 ** ^If the blob handle being closed was opened for read-write access, and if 5970 ** the database is in auto-commit mode and there are no other open read-write 5971 ** blob handles or active write statements, the current transaction is 5972 ** committed. ^If an error occurs while committing the transaction, an error 5973 ** code is returned and the transaction rolled back. 5974 ** 5975 ** Calling this function with an argument that is not a NULL pointer or an 5976 ** open blob handle results in undefined behaviour. ^Calling this routine 5977 ** with a null pointer (such as would be returned by a failed call to 5978 ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function 5979 ** is passed a valid open blob handle, the values returned by the 5980 ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. 5981 */ 5982 SQLITE_API int SQLITE_STDCALL sqlite3_blob_close(sqlite3_blob *); 5983 5984 /* 5985 ** CAPI3REF: Return The Size Of An Open BLOB 5986 ** METHOD: sqlite3_blob 5987 ** 5988 ** ^Returns the size in bytes of the BLOB accessible via the 5989 ** successfully opened [BLOB handle] in its only argument. ^The 5990 ** incremental blob I/O routines can only read or overwriting existing 5991 ** blob content; they cannot change the size of a blob. 5992 ** 5993 ** This routine only works on a [BLOB handle] which has been created 5994 ** by a prior successful call to [sqlite3_blob_open()] and which has not 5995 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 5996 ** to this routine results in undefined and probably undesirable behavior. 5997 */ 5998 SQLITE_API int SQLITE_STDCALL sqlite3_blob_bytes(sqlite3_blob *); 5999 6000 /* 6001 ** CAPI3REF: Read Data From A BLOB Incrementally 6002 ** METHOD: sqlite3_blob 6003 ** 6004 ** ^(This function is used to read data from an open [BLOB handle] into a 6005 ** caller-supplied buffer. N bytes of data are copied into buffer Z 6006 ** from the open BLOB, starting at offset iOffset.)^ 6007 ** 6008 ** ^If offset iOffset is less than N bytes from the end of the BLOB, 6009 ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is 6010 ** less than zero, [SQLITE_ERROR] is returned and no data is read. 6011 ** ^The size of the blob (and hence the maximum value of N+iOffset) 6012 ** can be determined using the [sqlite3_blob_bytes()] interface. 6013 ** 6014 ** ^An attempt to read from an expired [BLOB handle] fails with an 6015 ** error code of [SQLITE_ABORT]. 6016 ** 6017 ** ^(On success, sqlite3_blob_read() returns SQLITE_OK. 6018 ** Otherwise, an [error code] or an [extended error code] is returned.)^ 6019 ** 6020 ** This routine only works on a [BLOB handle] which has been created 6021 ** by a prior successful call to [sqlite3_blob_open()] and which has not 6022 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 6023 ** to this routine results in undefined and probably undesirable behavior. 6024 ** 6025 ** See also: [sqlite3_blob_write()]. 6026 */ 6027 SQLITE_API int SQLITE_STDCALL sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); 6028 6029 /* 6030 ** CAPI3REF: Write Data Into A BLOB Incrementally 6031 ** METHOD: sqlite3_blob 6032 ** 6033 ** ^(This function is used to write data into an open [BLOB handle] from a 6034 ** caller-supplied buffer. N bytes of data are copied from the buffer Z 6035 ** into the open BLOB, starting at offset iOffset.)^ 6036 ** 6037 ** ^(On success, sqlite3_blob_write() returns SQLITE_OK. 6038 ** Otherwise, an [error code] or an [extended error code] is returned.)^ 6039 ** ^Unless SQLITE_MISUSE is returned, this function sets the 6040 ** [database connection] error code and message accessible via 6041 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 6042 ** 6043 ** ^If the [BLOB handle] passed as the first argument was not opened for 6044 ** writing (the flags parameter to [sqlite3_blob_open()] was zero), 6045 ** this function returns [SQLITE_READONLY]. 6046 ** 6047 ** This function may only modify the contents of the BLOB; it is 6048 ** not possible to increase the size of a BLOB using this API. 6049 ** ^If offset iOffset is less than N bytes from the end of the BLOB, 6050 ** [SQLITE_ERROR] is returned and no data is written. The size of the 6051 ** BLOB (and hence the maximum value of N+iOffset) can be determined 6052 ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less 6053 ** than zero [SQLITE_ERROR] is returned and no data is written. 6054 ** 6055 ** ^An attempt to write to an expired [BLOB handle] fails with an 6056 ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred 6057 ** before the [BLOB handle] expired are not rolled back by the 6058 ** expiration of the handle, though of course those changes might 6059 ** have been overwritten by the statement that expired the BLOB handle 6060 ** or by other independent statements. 6061 ** 6062 ** This routine only works on a [BLOB handle] which has been created 6063 ** by a prior successful call to [sqlite3_blob_open()] and which has not 6064 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 6065 ** to this routine results in undefined and probably undesirable behavior. 6066 ** 6067 ** See also: [sqlite3_blob_read()]. 6068 */ 6069 SQLITE_API int SQLITE_STDCALL sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); 6070 6071 /* 6072 ** CAPI3REF: Virtual File System Objects 6073 ** 6074 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object 6075 ** that SQLite uses to interact 6076 ** with the underlying operating system. Most SQLite builds come with a 6077 ** single default VFS that is appropriate for the host computer. 6078 ** New VFSes can be registered and existing VFSes can be unregistered. 6079 ** The following interfaces are provided. 6080 ** 6081 ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. 6082 ** ^Names are case sensitive. 6083 ** ^Names are zero-terminated UTF-8 strings. 6084 ** ^If there is no match, a NULL pointer is returned. 6085 ** ^If zVfsName is NULL then the default VFS is returned. 6086 ** 6087 ** ^New VFSes are registered with sqlite3_vfs_register(). 6088 ** ^Each new VFS becomes the default VFS if the makeDflt flag is set. 6089 ** ^The same VFS can be registered multiple times without injury. 6090 ** ^To make an existing VFS into the default VFS, register it again 6091 ** with the makeDflt flag set. If two different VFSes with the 6092 ** same name are registered, the behavior is undefined. If a 6093 ** VFS is registered with a name that is NULL or an empty string, 6094 ** then the behavior is undefined. 6095 ** 6096 ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. 6097 ** ^(If the default VFS is unregistered, another VFS is chosen as 6098 ** the default. The choice for the new VFS is arbitrary.)^ 6099 */ 6100 SQLITE_API sqlite3_vfs *SQLITE_STDCALL sqlite3_vfs_find(const char *zVfsName); 6101 SQLITE_API int SQLITE_STDCALL sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); 6102 SQLITE_API int SQLITE_STDCALL sqlite3_vfs_unregister(sqlite3_vfs*); 6103 6104 /* 6105 ** CAPI3REF: Mutexes 6106 ** 6107 ** The SQLite core uses these routines for thread 6108 ** synchronization. Though they are intended for internal 6109 ** use by SQLite, code that links against SQLite is 6110 ** permitted to use any of these routines. 6111 ** 6112 ** The SQLite source code contains multiple implementations 6113 ** of these mutex routines. An appropriate implementation 6114 ** is selected automatically at compile-time. The following 6115 ** implementations are available in the SQLite core: 6116 ** 6117 ** <ul> 6118 ** <li> SQLITE_MUTEX_PTHREADS 6119 ** <li> SQLITE_MUTEX_W32 6120 ** <li> SQLITE_MUTEX_NOOP 6121 ** </ul> 6122 ** 6123 ** The SQLITE_MUTEX_NOOP implementation is a set of routines 6124 ** that does no real locking and is appropriate for use in 6125 ** a single-threaded application. The SQLITE_MUTEX_PTHREADS and 6126 ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix 6127 ** and Windows. 6128 ** 6129 ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor 6130 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex 6131 ** implementation is included with the library. In this case the 6132 ** application must supply a custom mutex implementation using the 6133 ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function 6134 ** before calling sqlite3_initialize() or any other public sqlite3_ 6135 ** function that calls sqlite3_initialize(). 6136 ** 6137 ** ^The sqlite3_mutex_alloc() routine allocates a new 6138 ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() 6139 ** routine returns NULL if it is unable to allocate the requested 6140 ** mutex. The argument to sqlite3_mutex_alloc() must one of these 6141 ** integer constants: 6142 ** 6143 ** <ul> 6144 ** <li> SQLITE_MUTEX_FAST 6145 ** <li> SQLITE_MUTEX_RECURSIVE 6146 ** <li> SQLITE_MUTEX_STATIC_MASTER 6147 ** <li> SQLITE_MUTEX_STATIC_MEM 6148 ** <li> SQLITE_MUTEX_STATIC_OPEN 6149 ** <li> SQLITE_MUTEX_STATIC_PRNG 6150 ** <li> SQLITE_MUTEX_STATIC_LRU 6151 ** <li> SQLITE_MUTEX_STATIC_PMEM 6152 ** <li> SQLITE_MUTEX_STATIC_APP1 6153 ** <li> SQLITE_MUTEX_STATIC_APP2 6154 ** <li> SQLITE_MUTEX_STATIC_APP3 6155 ** <li> SQLITE_MUTEX_STATIC_VFS1 6156 ** <li> SQLITE_MUTEX_STATIC_VFS2 6157 ** <li> SQLITE_MUTEX_STATIC_VFS3 6158 ** </ul> 6159 ** 6160 ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) 6161 ** cause sqlite3_mutex_alloc() to create 6162 ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE 6163 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. 6164 ** The mutex implementation does not need to make a distinction 6165 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does 6166 ** not want to. SQLite will only request a recursive mutex in 6167 ** cases where it really needs one. If a faster non-recursive mutex 6168 ** implementation is available on the host platform, the mutex subsystem 6169 ** might return such a mutex in response to SQLITE_MUTEX_FAST. 6170 ** 6171 ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other 6172 ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return 6173 ** a pointer to a static preexisting mutex. ^Nine static mutexes are 6174 ** used by the current version of SQLite. Future versions of SQLite 6175 ** may add additional static mutexes. Static mutexes are for internal 6176 ** use by SQLite only. Applications that use SQLite mutexes should 6177 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or 6178 ** SQLITE_MUTEX_RECURSIVE. 6179 ** 6180 ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST 6181 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() 6182 ** returns a different mutex on every call. ^For the static 6183 ** mutex types, the same mutex is returned on every call that has 6184 ** the same type number. 6185 ** 6186 ** ^The sqlite3_mutex_free() routine deallocates a previously 6187 ** allocated dynamic mutex. Attempting to deallocate a static 6188 ** mutex results in undefined behavior. 6189 ** 6190 ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt 6191 ** to enter a mutex. ^If another thread is already within the mutex, 6192 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return 6193 ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] 6194 ** upon successful entry. ^(Mutexes created using 6195 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. 6196 ** In such cases, the 6197 ** mutex must be exited an equal number of times before another thread 6198 ** can enter.)^ If the same thread tries to enter any mutex other 6199 ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. 6200 ** 6201 ** ^(Some systems (for example, Windows 95) do not support the operation 6202 ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() 6203 ** will always return SQLITE_BUSY. The SQLite core only ever uses 6204 ** sqlite3_mutex_try() as an optimization so this is acceptable 6205 ** behavior.)^ 6206 ** 6207 ** ^The sqlite3_mutex_leave() routine exits a mutex that was 6208 ** previously entered by the same thread. The behavior 6209 ** is undefined if the mutex is not currently entered by the 6210 ** calling thread or is not currently allocated. 6211 ** 6212 ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or 6213 ** sqlite3_mutex_leave() is a NULL pointer, then all three routines 6214 ** behave as no-ops. 6215 ** 6216 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. 6217 */ 6218 SQLITE_API sqlite3_mutex *SQLITE_STDCALL sqlite3_mutex_alloc(int); 6219 SQLITE_API void SQLITE_STDCALL sqlite3_mutex_free(sqlite3_mutex*); 6220 SQLITE_API void SQLITE_STDCALL sqlite3_mutex_enter(sqlite3_mutex*); 6221 SQLITE_API int SQLITE_STDCALL sqlite3_mutex_try(sqlite3_mutex*); 6222 SQLITE_API void SQLITE_STDCALL sqlite3_mutex_leave(sqlite3_mutex*); 6223 6224 /* 6225 ** CAPI3REF: Mutex Methods Object 6226 ** 6227 ** An instance of this structure defines the low-level routines 6228 ** used to allocate and use mutexes. 6229 ** 6230 ** Usually, the default mutex implementations provided by SQLite are 6231 ** sufficient, however the application has the option of substituting a custom 6232 ** implementation for specialized deployments or systems for which SQLite 6233 ** does not provide a suitable implementation. In this case, the application 6234 ** creates and populates an instance of this structure to pass 6235 ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. 6236 ** Additionally, an instance of this structure can be used as an 6237 ** output variable when querying the system for the current mutex 6238 ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. 6239 ** 6240 ** ^The xMutexInit method defined by this structure is invoked as 6241 ** part of system initialization by the sqlite3_initialize() function. 6242 ** ^The xMutexInit routine is called by SQLite exactly once for each 6243 ** effective call to [sqlite3_initialize()]. 6244 ** 6245 ** ^The xMutexEnd method defined by this structure is invoked as 6246 ** part of system shutdown by the sqlite3_shutdown() function. The 6247 ** implementation of this method is expected to release all outstanding 6248 ** resources obtained by the mutex methods implementation, especially 6249 ** those obtained by the xMutexInit method. ^The xMutexEnd() 6250 ** interface is invoked exactly once for each call to [sqlite3_shutdown()]. 6251 ** 6252 ** ^(The remaining seven methods defined by this structure (xMutexAlloc, 6253 ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and 6254 ** xMutexNotheld) implement the following interfaces (respectively): 6255 ** 6256 ** <ul> 6257 ** <li> [sqlite3_mutex_alloc()] </li> 6258 ** <li> [sqlite3_mutex_free()] </li> 6259 ** <li> [sqlite3_mutex_enter()] </li> 6260 ** <li> [sqlite3_mutex_try()] </li> 6261 ** <li> [sqlite3_mutex_leave()] </li> 6262 ** <li> [sqlite3_mutex_held()] </li> 6263 ** <li> [sqlite3_mutex_notheld()] </li> 6264 ** </ul>)^ 6265 ** 6266 ** The only difference is that the public sqlite3_XXX functions enumerated 6267 ** above silently ignore any invocations that pass a NULL pointer instead 6268 ** of a valid mutex handle. The implementations of the methods defined 6269 ** by this structure are not required to handle this case, the results 6270 ** of passing a NULL pointer instead of a valid mutex handle are undefined 6271 ** (i.e. it is acceptable to provide an implementation that segfaults if 6272 ** it is passed a NULL pointer). 6273 ** 6274 ** The xMutexInit() method must be threadsafe. It must be harmless to 6275 ** invoke xMutexInit() multiple times within the same process and without 6276 ** intervening calls to xMutexEnd(). Second and subsequent calls to 6277 ** xMutexInit() must be no-ops. 6278 ** 6279 ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] 6280 ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory 6281 ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite 6282 ** memory allocation for a fast or recursive mutex. 6283 ** 6284 ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is 6285 ** called, but only if the prior call to xMutexInit returned SQLITE_OK. 6286 ** If xMutexInit fails in any way, it is expected to clean up after itself 6287 ** prior to returning. 6288 */ 6289 typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; 6290 struct sqlite3_mutex_methods { 6291 int (*xMutexInit)(void); 6292 int (*xMutexEnd)(void); 6293 sqlite3_mutex *(*xMutexAlloc)(int); 6294 void (*xMutexFree)(sqlite3_mutex *); 6295 void (*xMutexEnter)(sqlite3_mutex *); 6296 int (*xMutexTry)(sqlite3_mutex *); 6297 void (*xMutexLeave)(sqlite3_mutex *); 6298 int (*xMutexHeld)(sqlite3_mutex *); 6299 int (*xMutexNotheld)(sqlite3_mutex *); 6300 }; 6301 6302 /* 6303 ** CAPI3REF: Mutex Verification Routines 6304 ** 6305 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines 6306 ** are intended for use inside assert() statements. The SQLite core 6307 ** never uses these routines except inside an assert() and applications 6308 ** are advised to follow the lead of the core. The SQLite core only 6309 ** provides implementations for these routines when it is compiled 6310 ** with the SQLITE_DEBUG flag. External mutex implementations 6311 ** are only required to provide these routines if SQLITE_DEBUG is 6312 ** defined and if NDEBUG is not defined. 6313 ** 6314 ** These routines should return true if the mutex in their argument 6315 ** is held or not held, respectively, by the calling thread. 6316 ** 6317 ** The implementation is not required to provide versions of these 6318 ** routines that actually work. If the implementation does not provide working 6319 ** versions of these routines, it should at least provide stubs that always 6320 ** return true so that one does not get spurious assertion failures. 6321 ** 6322 ** If the argument to sqlite3_mutex_held() is a NULL pointer then 6323 ** the routine should return 1. This seems counter-intuitive since 6324 ** clearly the mutex cannot be held if it does not exist. But 6325 ** the reason the mutex does not exist is because the build is not 6326 ** using mutexes. And we do not want the assert() containing the 6327 ** call to sqlite3_mutex_held() to fail, so a non-zero return is 6328 ** the appropriate thing to do. The sqlite3_mutex_notheld() 6329 ** interface should also return 1 when given a NULL pointer. 6330 */ 6331 #ifndef NDEBUG 6332 SQLITE_API int SQLITE_STDCALL sqlite3_mutex_held(sqlite3_mutex*); 6333 SQLITE_API int SQLITE_STDCALL sqlite3_mutex_notheld(sqlite3_mutex*); 6334 #endif 6335 6336 /* 6337 ** CAPI3REF: Mutex Types 6338 ** 6339 ** The [sqlite3_mutex_alloc()] interface takes a single argument 6340 ** which is one of these integer constants. 6341 ** 6342 ** The set of static mutexes may change from one SQLite release to the 6343 ** next. Applications that override the built-in mutex logic must be 6344 ** prepared to accommodate additional static mutexes. 6345 */ 6346 #define SQLITE_MUTEX_FAST 0 6347 #define SQLITE_MUTEX_RECURSIVE 1 6348 #define SQLITE_MUTEX_STATIC_MASTER 2 6349 #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ 6350 #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ 6351 #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ 6352 #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */ 6353 #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ 6354 #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ 6355 #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ 6356 #define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ 6357 #define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ 6358 #define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ 6359 #define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ 6360 #define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ 6361 #define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ 6362 6363 /* 6364 ** CAPI3REF: Retrieve the mutex for a database connection 6365 ** METHOD: sqlite3 6366 ** 6367 ** ^This interface returns a pointer the [sqlite3_mutex] object that 6368 ** serializes access to the [database connection] given in the argument 6369 ** when the [threading mode] is Serialized. 6370 ** ^If the [threading mode] is Single-thread or Multi-thread then this 6371 ** routine returns a NULL pointer. 6372 */ 6373 SQLITE_API sqlite3_mutex *SQLITE_STDCALL sqlite3_db_mutex(sqlite3*); 6374 6375 /* 6376 ** CAPI3REF: Low-Level Control Of Database Files 6377 ** METHOD: sqlite3 6378 ** 6379 ** ^The [sqlite3_file_control()] interface makes a direct call to the 6380 ** xFileControl method for the [sqlite3_io_methods] object associated 6381 ** with a particular database identified by the second argument. ^The 6382 ** name of the database is "main" for the main database or "temp" for the 6383 ** TEMP database, or the name that appears after the AS keyword for 6384 ** databases that are added using the [ATTACH] SQL command. 6385 ** ^A NULL pointer can be used in place of "main" to refer to the 6386 ** main database file. 6387 ** ^The third and fourth parameters to this routine 6388 ** are passed directly through to the second and third parameters of 6389 ** the xFileControl method. ^The return value of the xFileControl 6390 ** method becomes the return value of this routine. 6391 ** 6392 ** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes 6393 ** a pointer to the underlying [sqlite3_file] object to be written into 6394 ** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER 6395 ** case is a short-circuit path which does not actually invoke the 6396 ** underlying sqlite3_io_methods.xFileControl method. 6397 ** 6398 ** ^If the second parameter (zDbName) does not match the name of any 6399 ** open database file, then SQLITE_ERROR is returned. ^This error 6400 ** code is not remembered and will not be recalled by [sqlite3_errcode()] 6401 ** or [sqlite3_errmsg()]. The underlying xFileControl method might 6402 ** also return SQLITE_ERROR. There is no way to distinguish between 6403 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying 6404 ** xFileControl method. 6405 ** 6406 ** See also: [SQLITE_FCNTL_LOCKSTATE] 6407 */ 6408 SQLITE_API int SQLITE_STDCALL sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); 6409 6410 /* 6411 ** CAPI3REF: Testing Interface 6412 ** 6413 ** ^The sqlite3_test_control() interface is used to read out internal 6414 ** state of SQLite and to inject faults into SQLite for testing 6415 ** purposes. ^The first parameter is an operation code that determines 6416 ** the number, meaning, and operation of all subsequent parameters. 6417 ** 6418 ** This interface is not for use by applications. It exists solely 6419 ** for verifying the correct operation of the SQLite library. Depending 6420 ** on how the SQLite library is compiled, this interface might not exist. 6421 ** 6422 ** The details of the operation codes, their meanings, the parameters 6423 ** they take, and what they do are all subject to change without notice. 6424 ** Unlike most of the SQLite API, this function is not guaranteed to 6425 ** operate consistently from one release to the next. 6426 */ 6427 SQLITE_API int SQLITE_CDECL sqlite3_test_control(int op, ...); 6428 6429 /* 6430 ** CAPI3REF: Testing Interface Operation Codes 6431 ** 6432 ** These constants are the valid operation code parameters used 6433 ** as the first argument to [sqlite3_test_control()]. 6434 ** 6435 ** These parameters and their meanings are subject to change 6436 ** without notice. These values are for testing purposes only. 6437 ** Applications should not use any of these parameters or the 6438 ** [sqlite3_test_control()] interface. 6439 */ 6440 #define SQLITE_TESTCTRL_FIRST 5 6441 #define SQLITE_TESTCTRL_PRNG_SAVE 5 6442 #define SQLITE_TESTCTRL_PRNG_RESTORE 6 6443 #define SQLITE_TESTCTRL_PRNG_RESET 7 6444 #define SQLITE_TESTCTRL_BITVEC_TEST 8 6445 #define SQLITE_TESTCTRL_FAULT_INSTALL 9 6446 #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 6447 #define SQLITE_TESTCTRL_PENDING_BYTE 11 6448 #define SQLITE_TESTCTRL_ASSERT 12 6449 #define SQLITE_TESTCTRL_ALWAYS 13 6450 #define SQLITE_TESTCTRL_RESERVE 14 6451 #define SQLITE_TESTCTRL_OPTIMIZATIONS 15 6452 #define SQLITE_TESTCTRL_ISKEYWORD 16 6453 #define SQLITE_TESTCTRL_SCRATCHMALLOC 17 6454 #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 6455 #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ 6456 #define SQLITE_TESTCTRL_NEVER_CORRUPT 20 6457 #define SQLITE_TESTCTRL_VDBE_COVERAGE 21 6458 #define SQLITE_TESTCTRL_BYTEORDER 22 6459 #define SQLITE_TESTCTRL_ISINIT 23 6460 #define SQLITE_TESTCTRL_SORTER_MMAP 24 6461 #define SQLITE_TESTCTRL_IMPOSTER 25 6462 #define SQLITE_TESTCTRL_LAST 25 6463 6464 /* 6465 ** CAPI3REF: SQLite Runtime Status 6466 ** 6467 ** ^These interfaces are used to retrieve runtime status information 6468 ** about the performance of SQLite, and optionally to reset various 6469 ** highwater marks. ^The first argument is an integer code for 6470 ** the specific parameter to measure. ^(Recognized integer codes 6471 ** are of the form [status parameters | SQLITE_STATUS_...].)^ 6472 ** ^The current value of the parameter is returned into *pCurrent. 6473 ** ^The highest recorded value is returned in *pHighwater. ^If the 6474 ** resetFlag is true, then the highest record value is reset after 6475 ** *pHighwater is written. ^(Some parameters do not record the highest 6476 ** value. For those parameters 6477 ** nothing is written into *pHighwater and the resetFlag is ignored.)^ 6478 ** ^(Other parameters record only the highwater mark and not the current 6479 ** value. For these latter parameters nothing is written into *pCurrent.)^ 6480 ** 6481 ** ^The sqlite3_status() and sqlite3_status64() routines return 6482 ** SQLITE_OK on success and a non-zero [error code] on failure. 6483 ** 6484 ** If either the current value or the highwater mark is too large to 6485 ** be represented by a 32-bit integer, then the values returned by 6486 ** sqlite3_status() are undefined. 6487 ** 6488 ** See also: [sqlite3_db_status()] 6489 */ 6490 SQLITE_API int SQLITE_STDCALL sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); 6491 SQLITE_API int SQLITE_STDCALL sqlite3_status64( 6492 int op, 6493 sqlite3_int64 *pCurrent, 6494 sqlite3_int64 *pHighwater, 6495 int resetFlag 6496 ); 6497 6498 6499 /* 6500 ** CAPI3REF: Status Parameters 6501 ** KEYWORDS: {status parameters} 6502 ** 6503 ** These integer constants designate various run-time status parameters 6504 ** that can be returned by [sqlite3_status()]. 6505 ** 6506 ** <dl> 6507 ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> 6508 ** <dd>This parameter is the current amount of memory checked out 6509 ** using [sqlite3_malloc()], either directly or indirectly. The 6510 ** figure includes calls made to [sqlite3_malloc()] by the application 6511 ** and internal memory usage by the SQLite library. Scratch memory 6512 ** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache 6513 ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in 6514 ** this parameter. The amount returned is the sum of the allocation 6515 ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ 6516 ** 6517 ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> 6518 ** <dd>This parameter records the largest memory allocation request 6519 ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their 6520 ** internal equivalents). Only the value returned in the 6521 ** *pHighwater parameter to [sqlite3_status()] is of interest. 6522 ** The value written into the *pCurrent parameter is undefined.</dd>)^ 6523 ** 6524 ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> 6525 ** <dd>This parameter records the number of separate memory allocations 6526 ** currently checked out.</dd>)^ 6527 ** 6528 ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> 6529 ** <dd>This parameter returns the number of pages used out of the 6530 ** [pagecache memory allocator] that was configured using 6531 ** [SQLITE_CONFIG_PAGECACHE]. The 6532 ** value returned is in pages, not in bytes.</dd>)^ 6533 ** 6534 ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] 6535 ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> 6536 ** <dd>This parameter returns the number of bytes of page cache 6537 ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] 6538 ** buffer and where forced to overflow to [sqlite3_malloc()]. The 6539 ** returned value includes allocations that overflowed because they 6540 ** where too large (they were larger than the "sz" parameter to 6541 ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because 6542 ** no space was left in the page cache.</dd>)^ 6543 ** 6544 ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> 6545 ** <dd>This parameter records the largest memory allocation request 6546 ** handed to [pagecache memory allocator]. Only the value returned in the 6547 ** *pHighwater parameter to [sqlite3_status()] is of interest. 6548 ** The value written into the *pCurrent parameter is undefined.</dd>)^ 6549 ** 6550 ** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt> 6551 ** <dd>This parameter returns the number of allocations used out of the 6552 ** [scratch memory allocator] configured using 6553 ** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not 6554 ** in bytes. Since a single thread may only have one scratch allocation 6555 ** outstanding at time, this parameter also reports the number of threads 6556 ** using scratch memory at the same time.</dd>)^ 6557 ** 6558 ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> 6559 ** <dd>This parameter returns the number of bytes of scratch memory 6560 ** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH] 6561 ** buffer and where forced to overflow to [sqlite3_malloc()]. The values 6562 ** returned include overflows because the requested allocation was too 6563 ** larger (that is, because the requested allocation was larger than the 6564 ** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer 6565 ** slots were available. 6566 ** </dd>)^ 6567 ** 6568 ** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt> 6569 ** <dd>This parameter records the largest memory allocation request 6570 ** handed to [scratch memory allocator]. Only the value returned in the 6571 ** *pHighwater parameter to [sqlite3_status()] is of interest. 6572 ** The value written into the *pCurrent parameter is undefined.</dd>)^ 6573 ** 6574 ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> 6575 ** <dd>This parameter records the deepest parser stack. It is only 6576 ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ 6577 ** </dl> 6578 ** 6579 ** New status parameters may be added from time to time. 6580 */ 6581 #define SQLITE_STATUS_MEMORY_USED 0 6582 #define SQLITE_STATUS_PAGECACHE_USED 1 6583 #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 6584 #define SQLITE_STATUS_SCRATCH_USED 3 6585 #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 6586 #define SQLITE_STATUS_MALLOC_SIZE 5 6587 #define SQLITE_STATUS_PARSER_STACK 6 6588 #define SQLITE_STATUS_PAGECACHE_SIZE 7 6589 #define SQLITE_STATUS_SCRATCH_SIZE 8 6590 #define SQLITE_STATUS_MALLOC_COUNT 9 6591 6592 /* 6593 ** CAPI3REF: Database Connection Status 6594 ** METHOD: sqlite3 6595 ** 6596 ** ^This interface is used to retrieve runtime status information 6597 ** about a single [database connection]. ^The first argument is the 6598 ** database connection object to be interrogated. ^The second argument 6599 ** is an integer constant, taken from the set of 6600 ** [SQLITE_DBSTATUS options], that 6601 ** determines the parameter to interrogate. The set of 6602 ** [SQLITE_DBSTATUS options] is likely 6603 ** to grow in future releases of SQLite. 6604 ** 6605 ** ^The current value of the requested parameter is written into *pCur 6606 ** and the highest instantaneous value is written into *pHiwtr. ^If 6607 ** the resetFlg is true, then the highest instantaneous value is 6608 ** reset back down to the current value. 6609 ** 6610 ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a 6611 ** non-zero [error code] on failure. 6612 ** 6613 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. 6614 */ 6615 SQLITE_API int SQLITE_STDCALL sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); 6616 6617 /* 6618 ** CAPI3REF: Status Parameters for database connections 6619 ** KEYWORDS: {SQLITE_DBSTATUS options} 6620 ** 6621 ** These constants are the available integer "verbs" that can be passed as 6622 ** the second argument to the [sqlite3_db_status()] interface. 6623 ** 6624 ** New verbs may be added in future releases of SQLite. Existing verbs 6625 ** might be discontinued. Applications should check the return code from 6626 ** [sqlite3_db_status()] to make sure that the call worked. 6627 ** The [sqlite3_db_status()] interface will return a non-zero error code 6628 ** if a discontinued or unsupported verb is invoked. 6629 ** 6630 ** <dl> 6631 ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> 6632 ** <dd>This parameter returns the number of lookaside memory slots currently 6633 ** checked out.</dd>)^ 6634 ** 6635 ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> 6636 ** <dd>This parameter returns the number malloc attempts that were 6637 ** satisfied using lookaside memory. Only the high-water value is meaningful; 6638 ** the current value is always zero.)^ 6639 ** 6640 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] 6641 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> 6642 ** <dd>This parameter returns the number malloc attempts that might have 6643 ** been satisfied using lookaside memory but failed due to the amount of 6644 ** memory requested being larger than the lookaside slot size. 6645 ** Only the high-water value is meaningful; 6646 ** the current value is always zero.)^ 6647 ** 6648 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] 6649 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> 6650 ** <dd>This parameter returns the number malloc attempts that might have 6651 ** been satisfied using lookaside memory but failed due to all lookaside 6652 ** memory already being in use. 6653 ** Only the high-water value is meaningful; 6654 ** the current value is always zero.)^ 6655 ** 6656 ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> 6657 ** <dd>This parameter returns the approximate number of bytes of heap 6658 ** memory used by all pager caches associated with the database connection.)^ 6659 ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. 6660 ** 6661 ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> 6662 ** <dd>This parameter returns the approximate number of bytes of heap 6663 ** memory used to store the schema for all databases associated 6664 ** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 6665 ** ^The full amount of memory used by the schemas is reported, even if the 6666 ** schema memory is shared with other database connections due to 6667 ** [shared cache mode] being enabled. 6668 ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. 6669 ** 6670 ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> 6671 ** <dd>This parameter returns the approximate number of bytes of heap 6672 ** and lookaside memory used by all prepared statements associated with 6673 ** the database connection.)^ 6674 ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. 6675 ** </dd> 6676 ** 6677 ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> 6678 ** <dd>This parameter returns the number of pager cache hits that have 6679 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT 6680 ** is always 0. 6681 ** </dd> 6682 ** 6683 ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> 6684 ** <dd>This parameter returns the number of pager cache misses that have 6685 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS 6686 ** is always 0. 6687 ** </dd> 6688 ** 6689 ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> 6690 ** <dd>This parameter returns the number of dirty cache entries that have 6691 ** been written to disk. Specifically, the number of pages written to the 6692 ** wal file in wal mode databases, or the number of pages written to the 6693 ** database file in rollback mode databases. Any pages written as part of 6694 ** transaction rollback or database recovery operations are not included. 6695 ** If an IO or other error occurs while writing a page to disk, the effect 6696 ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The 6697 ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. 6698 ** </dd> 6699 ** 6700 ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> 6701 ** <dd>This parameter returns zero for the current value if and only if 6702 ** all foreign key constraints (deferred or immediate) have been 6703 ** resolved.)^ ^The highwater mark is always 0. 6704 ** </dd> 6705 ** </dl> 6706 */ 6707 #define SQLITE_DBSTATUS_LOOKASIDE_USED 0 6708 #define SQLITE_DBSTATUS_CACHE_USED 1 6709 #define SQLITE_DBSTATUS_SCHEMA_USED 2 6710 #define SQLITE_DBSTATUS_STMT_USED 3 6711 #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 6712 #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 6713 #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 6714 #define SQLITE_DBSTATUS_CACHE_HIT 7 6715 #define SQLITE_DBSTATUS_CACHE_MISS 8 6716 #define SQLITE_DBSTATUS_CACHE_WRITE 9 6717 #define SQLITE_DBSTATUS_DEFERRED_FKS 10 6718 #define SQLITE_DBSTATUS_MAX 10 /* Largest defined DBSTATUS */ 6719 6720 6721 /* 6722 ** CAPI3REF: Prepared Statement Status 6723 ** METHOD: sqlite3_stmt 6724 ** 6725 ** ^(Each prepared statement maintains various 6726 ** [SQLITE_STMTSTATUS counters] that measure the number 6727 ** of times it has performed specific operations.)^ These counters can 6728 ** be used to monitor the performance characteristics of the prepared 6729 ** statements. For example, if the number of table steps greatly exceeds 6730 ** the number of table searches or result rows, that would tend to indicate 6731 ** that the prepared statement is using a full table scan rather than 6732 ** an index. 6733 ** 6734 ** ^(This interface is used to retrieve and reset counter values from 6735 ** a [prepared statement]. The first argument is the prepared statement 6736 ** object to be interrogated. The second argument 6737 ** is an integer code for a specific [SQLITE_STMTSTATUS counter] 6738 ** to be interrogated.)^ 6739 ** ^The current value of the requested counter is returned. 6740 ** ^If the resetFlg is true, then the counter is reset to zero after this 6741 ** interface call returns. 6742 ** 6743 ** See also: [sqlite3_status()] and [sqlite3_db_status()]. 6744 */ 6745 SQLITE_API int SQLITE_STDCALL sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); 6746 6747 /* 6748 ** CAPI3REF: Status Parameters for prepared statements 6749 ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} 6750 ** 6751 ** These preprocessor macros define integer codes that name counter 6752 ** values associated with the [sqlite3_stmt_status()] interface. 6753 ** The meanings of the various counters are as follows: 6754 ** 6755 ** <dl> 6756 ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> 6757 ** <dd>^This is the number of times that SQLite has stepped forward in 6758 ** a table as part of a full table scan. Large numbers for this counter 6759 ** may indicate opportunities for performance improvement through 6760 ** careful use of indices.</dd> 6761 ** 6762 ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> 6763 ** <dd>^This is the number of sort operations that have occurred. 6764 ** A non-zero value in this counter may indicate an opportunity to 6765 ** improvement performance through careful use of indices.</dd> 6766 ** 6767 ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> 6768 ** <dd>^This is the number of rows inserted into transient indices that 6769 ** were created automatically in order to help joins run faster. 6770 ** A non-zero value in this counter may indicate an opportunity to 6771 ** improvement performance by adding permanent indices that do not 6772 ** need to be reinitialized each time the statement is run.</dd> 6773 ** 6774 ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> 6775 ** <dd>^This is the number of virtual machine operations executed 6776 ** by the prepared statement if that number is less than or equal 6777 ** to 2147483647. The number of virtual machine operations can be 6778 ** used as a proxy for the total work done by the prepared statement. 6779 ** If the number of virtual machine operations exceeds 2147483647 6780 ** then the value returned by this statement status code is undefined. 6781 ** </dd> 6782 ** </dl> 6783 */ 6784 #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 6785 #define SQLITE_STMTSTATUS_SORT 2 6786 #define SQLITE_STMTSTATUS_AUTOINDEX 3 6787 #define SQLITE_STMTSTATUS_VM_STEP 4 6788 6789 /* 6790 ** CAPI3REF: Custom Page Cache Object 6791 ** 6792 ** The sqlite3_pcache type is opaque. It is implemented by 6793 ** the pluggable module. The SQLite core has no knowledge of 6794 ** its size or internal structure and never deals with the 6795 ** sqlite3_pcache object except by holding and passing pointers 6796 ** to the object. 6797 ** 6798 ** See [sqlite3_pcache_methods2] for additional information. 6799 */ 6800 typedef struct sqlite3_pcache sqlite3_pcache; 6801 6802 /* 6803 ** CAPI3REF: Custom Page Cache Object 6804 ** 6805 ** The sqlite3_pcache_page object represents a single page in the 6806 ** page cache. The page cache will allocate instances of this 6807 ** object. Various methods of the page cache use pointers to instances 6808 ** of this object as parameters or as their return value. 6809 ** 6810 ** See [sqlite3_pcache_methods2] for additional information. 6811 */ 6812 typedef struct sqlite3_pcache_page sqlite3_pcache_page; 6813 struct sqlite3_pcache_page { 6814 void *pBuf; /* The content of the page */ 6815 void *pExtra; /* Extra information associated with the page */ 6816 }; 6817 6818 /* 6819 ** CAPI3REF: Application Defined Page Cache. 6820 ** KEYWORDS: {page cache} 6821 ** 6822 ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can 6823 ** register an alternative page cache implementation by passing in an 6824 ** instance of the sqlite3_pcache_methods2 structure.)^ 6825 ** In many applications, most of the heap memory allocated by 6826 ** SQLite is used for the page cache. 6827 ** By implementing a 6828 ** custom page cache using this API, an application can better control 6829 ** the amount of memory consumed by SQLite, the way in which 6830 ** that memory is allocated and released, and the policies used to 6831 ** determine exactly which parts of a database file are cached and for 6832 ** how long. 6833 ** 6834 ** The alternative page cache mechanism is an 6835 ** extreme measure that is only needed by the most demanding applications. 6836 ** The built-in page cache is recommended for most uses. 6837 ** 6838 ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an 6839 ** internal buffer by SQLite within the call to [sqlite3_config]. Hence 6840 ** the application may discard the parameter after the call to 6841 ** [sqlite3_config()] returns.)^ 6842 ** 6843 ** [[the xInit() page cache method]] 6844 ** ^(The xInit() method is called once for each effective 6845 ** call to [sqlite3_initialize()])^ 6846 ** (usually only once during the lifetime of the process). ^(The xInit() 6847 ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ 6848 ** The intent of the xInit() method is to set up global data structures 6849 ** required by the custom page cache implementation. 6850 ** ^(If the xInit() method is NULL, then the 6851 ** built-in default page cache is used instead of the application defined 6852 ** page cache.)^ 6853 ** 6854 ** [[the xShutdown() page cache method]] 6855 ** ^The xShutdown() method is called by [sqlite3_shutdown()]. 6856 ** It can be used to clean up 6857 ** any outstanding resources before process shutdown, if required. 6858 ** ^The xShutdown() method may be NULL. 6859 ** 6860 ** ^SQLite automatically serializes calls to the xInit method, 6861 ** so the xInit method need not be threadsafe. ^The 6862 ** xShutdown method is only called from [sqlite3_shutdown()] so it does 6863 ** not need to be threadsafe either. All other methods must be threadsafe 6864 ** in multithreaded applications. 6865 ** 6866 ** ^SQLite will never invoke xInit() more than once without an intervening 6867 ** call to xShutdown(). 6868 ** 6869 ** [[the xCreate() page cache methods]] 6870 ** ^SQLite invokes the xCreate() method to construct a new cache instance. 6871 ** SQLite will typically create one cache instance for each open database file, 6872 ** though this is not guaranteed. ^The 6873 ** first parameter, szPage, is the size in bytes of the pages that must 6874 ** be allocated by the cache. ^szPage will always a power of two. ^The 6875 ** second parameter szExtra is a number of bytes of extra storage 6876 ** associated with each page cache entry. ^The szExtra parameter will 6877 ** a number less than 250. SQLite will use the 6878 ** extra szExtra bytes on each page to store metadata about the underlying 6879 ** database page on disk. The value passed into szExtra depends 6880 ** on the SQLite version, the target platform, and how SQLite was compiled. 6881 ** ^The third argument to xCreate(), bPurgeable, is true if the cache being 6882 ** created will be used to cache database pages of a file stored on disk, or 6883 ** false if it is used for an in-memory database. The cache implementation 6884 ** does not have to do anything special based with the value of bPurgeable; 6885 ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will 6886 ** never invoke xUnpin() except to deliberately delete a page. 6887 ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to 6888 ** false will always have the "discard" flag set to true. 6889 ** ^Hence, a cache created with bPurgeable false will 6890 ** never contain any unpinned pages. 6891 ** 6892 ** [[the xCachesize() page cache method]] 6893 ** ^(The xCachesize() method may be called at any time by SQLite to set the 6894 ** suggested maximum cache-size (number of pages stored by) the cache 6895 ** instance passed as the first argument. This is the value configured using 6896 ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable 6897 ** parameter, the implementation is not required to do anything with this 6898 ** value; it is advisory only. 6899 ** 6900 ** [[the xPagecount() page cache methods]] 6901 ** The xPagecount() method must return the number of pages currently 6902 ** stored in the cache, both pinned and unpinned. 6903 ** 6904 ** [[the xFetch() page cache methods]] 6905 ** The xFetch() method locates a page in the cache and returns a pointer to 6906 ** an sqlite3_pcache_page object associated with that page, or a NULL pointer. 6907 ** The pBuf element of the returned sqlite3_pcache_page object will be a 6908 ** pointer to a buffer of szPage bytes used to store the content of a 6909 ** single database page. The pExtra element of sqlite3_pcache_page will be 6910 ** a pointer to the szExtra bytes of extra storage that SQLite has requested 6911 ** for each entry in the page cache. 6912 ** 6913 ** The page to be fetched is determined by the key. ^The minimum key value 6914 ** is 1. After it has been retrieved using xFetch, the page is considered 6915 ** to be "pinned". 6916 ** 6917 ** If the requested page is already in the page cache, then the page cache 6918 ** implementation must return a pointer to the page buffer with its content 6919 ** intact. If the requested page is not already in the cache, then the 6920 ** cache implementation should use the value of the createFlag 6921 ** parameter to help it determined what action to take: 6922 ** 6923 ** <table border=1 width=85% align=center> 6924 ** <tr><th> createFlag <th> Behavior when page is not already in cache 6925 ** <tr><td> 0 <td> Do not allocate a new page. Return NULL. 6926 ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. 6927 ** Otherwise return NULL. 6928 ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return 6929 ** NULL if allocating a new page is effectively impossible. 6930 ** </table> 6931 ** 6932 ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite 6933 ** will only use a createFlag of 2 after a prior call with a createFlag of 1 6934 ** failed.)^ In between the to xFetch() calls, SQLite may 6935 ** attempt to unpin one or more cache pages by spilling the content of 6936 ** pinned pages to disk and synching the operating system disk cache. 6937 ** 6938 ** [[the xUnpin() page cache method]] 6939 ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page 6940 ** as its second argument. If the third parameter, discard, is non-zero, 6941 ** then the page must be evicted from the cache. 6942 ** ^If the discard parameter is 6943 ** zero, then the page may be discarded or retained at the discretion of 6944 ** page cache implementation. ^The page cache implementation 6945 ** may choose to evict unpinned pages at any time. 6946 ** 6947 ** The cache must not perform any reference counting. A single 6948 ** call to xUnpin() unpins the page regardless of the number of prior calls 6949 ** to xFetch(). 6950 ** 6951 ** [[the xRekey() page cache methods]] 6952 ** The xRekey() method is used to change the key value associated with the 6953 ** page passed as the second argument. If the cache 6954 ** previously contains an entry associated with newKey, it must be 6955 ** discarded. ^Any prior cache entry associated with newKey is guaranteed not 6956 ** to be pinned. 6957 ** 6958 ** When SQLite calls the xTruncate() method, the cache must discard all 6959 ** existing cache entries with page numbers (keys) greater than or equal 6960 ** to the value of the iLimit parameter passed to xTruncate(). If any 6961 ** of these pages are pinned, they are implicitly unpinned, meaning that 6962 ** they can be safely discarded. 6963 ** 6964 ** [[the xDestroy() page cache method]] 6965 ** ^The xDestroy() method is used to delete a cache allocated by xCreate(). 6966 ** All resources associated with the specified cache should be freed. ^After 6967 ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] 6968 ** handle invalid, and will not use it with any other sqlite3_pcache_methods2 6969 ** functions. 6970 ** 6971 ** [[the xShrink() page cache method]] 6972 ** ^SQLite invokes the xShrink() method when it wants the page cache to 6973 ** free up as much of heap memory as possible. The page cache implementation 6974 ** is not obligated to free any memory, but well-behaved implementations should 6975 ** do their best. 6976 */ 6977 typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; 6978 struct sqlite3_pcache_methods2 { 6979 int iVersion; 6980 void *pArg; 6981 int (*xInit)(void*); 6982 void (*xShutdown)(void*); 6983 sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); 6984 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 6985 int (*xPagecount)(sqlite3_pcache*); 6986 sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 6987 void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); 6988 void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, 6989 unsigned oldKey, unsigned newKey); 6990 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 6991 void (*xDestroy)(sqlite3_pcache*); 6992 void (*xShrink)(sqlite3_pcache*); 6993 }; 6994 6995 /* 6996 ** This is the obsolete pcache_methods object that has now been replaced 6997 ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is 6998 ** retained in the header file for backwards compatibility only. 6999 */ 7000 typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; 7001 struct sqlite3_pcache_methods { 7002 void *pArg; 7003 int (*xInit)(void*); 7004 void (*xShutdown)(void*); 7005 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); 7006 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 7007 int (*xPagecount)(sqlite3_pcache*); 7008 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 7009 void (*xUnpin)(sqlite3_pcache*, void*, int discard); 7010 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); 7011 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 7012 void (*xDestroy)(sqlite3_pcache*); 7013 }; 7014 7015 7016 /* 7017 ** CAPI3REF: Online Backup Object 7018 ** 7019 ** The sqlite3_backup object records state information about an ongoing 7020 ** online backup operation. ^The sqlite3_backup object is created by 7021 ** a call to [sqlite3_backup_init()] and is destroyed by a call to 7022 ** [sqlite3_backup_finish()]. 7023 ** 7024 ** See Also: [Using the SQLite Online Backup API] 7025 */ 7026 typedef struct sqlite3_backup sqlite3_backup; 7027 7028 /* 7029 ** CAPI3REF: Online Backup API. 7030 ** 7031 ** The backup API copies the content of one database into another. 7032 ** It is useful either for creating backups of databases or 7033 ** for copying in-memory databases to or from persistent files. 7034 ** 7035 ** See Also: [Using the SQLite Online Backup API] 7036 ** 7037 ** ^SQLite holds a write transaction open on the destination database file 7038 ** for the duration of the backup operation. 7039 ** ^The source database is read-locked only while it is being read; 7040 ** it is not locked continuously for the entire backup operation. 7041 ** ^Thus, the backup may be performed on a live source database without 7042 ** preventing other database connections from 7043 ** reading or writing to the source database while the backup is underway. 7044 ** 7045 ** ^(To perform a backup operation: 7046 ** <ol> 7047 ** <li><b>sqlite3_backup_init()</b> is called once to initialize the 7048 ** backup, 7049 ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 7050 ** the data between the two databases, and finally 7051 ** <li><b>sqlite3_backup_finish()</b> is called to release all resources 7052 ** associated with the backup operation. 7053 ** </ol>)^ 7054 ** There should be exactly one call to sqlite3_backup_finish() for each 7055 ** successful call to sqlite3_backup_init(). 7056 ** 7057 ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> 7058 ** 7059 ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 7060 ** [database connection] associated with the destination database 7061 ** and the database name, respectively. 7062 ** ^The database name is "main" for the main database, "temp" for the 7063 ** temporary database, or the name specified after the AS keyword in 7064 ** an [ATTACH] statement for an attached database. 7065 ** ^The S and M arguments passed to 7066 ** sqlite3_backup_init(D,N,S,M) identify the [database connection] 7067 ** and database name of the source database, respectively. 7068 ** ^The source and destination [database connections] (parameters S and D) 7069 ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with 7070 ** an error. 7071 ** 7072 ** ^A call to sqlite3_backup_init() will fail, returning SQLITE_ERROR, if 7073 ** there is already a read or read-write transaction open on the 7074 ** destination database. 7075 ** 7076 ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is 7077 ** returned and an error code and error message are stored in the 7078 ** destination [database connection] D. 7079 ** ^The error code and message for the failed call to sqlite3_backup_init() 7080 ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or 7081 ** [sqlite3_errmsg16()] functions. 7082 ** ^A successful call to sqlite3_backup_init() returns a pointer to an 7083 ** [sqlite3_backup] object. 7084 ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and 7085 ** sqlite3_backup_finish() functions to perform the specified backup 7086 ** operation. 7087 ** 7088 ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> 7089 ** 7090 ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 7091 ** the source and destination databases specified by [sqlite3_backup] object B. 7092 ** ^If N is negative, all remaining source pages are copied. 7093 ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there 7094 ** are still more pages to be copied, then the function returns [SQLITE_OK]. 7095 ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages 7096 ** from source to destination, then it returns [SQLITE_DONE]. 7097 ** ^If an error occurs while running sqlite3_backup_step(B,N), 7098 ** then an [error code] is returned. ^As well as [SQLITE_OK] and 7099 ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], 7100 ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an 7101 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. 7102 ** 7103 ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if 7104 ** <ol> 7105 ** <li> the destination database was opened read-only, or 7106 ** <li> the destination database is using write-ahead-log journaling 7107 ** and the destination and source page sizes differ, or 7108 ** <li> the destination database is an in-memory database and the 7109 ** destination and source page sizes differ. 7110 ** </ol>)^ 7111 ** 7112 ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then 7113 ** the [sqlite3_busy_handler | busy-handler function] 7114 ** is invoked (if one is specified). ^If the 7115 ** busy-handler returns non-zero before the lock is available, then 7116 ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to 7117 ** sqlite3_backup_step() can be retried later. ^If the source 7118 ** [database connection] 7119 ** is being used to write to the source database when sqlite3_backup_step() 7120 ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this 7121 ** case the call to sqlite3_backup_step() can be retried later on. ^(If 7122 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or 7123 ** [SQLITE_READONLY] is returned, then 7124 ** there is no point in retrying the call to sqlite3_backup_step(). These 7125 ** errors are considered fatal.)^ The application must accept 7126 ** that the backup operation has failed and pass the backup operation handle 7127 ** to the sqlite3_backup_finish() to release associated resources. 7128 ** 7129 ** ^The first call to sqlite3_backup_step() obtains an exclusive lock 7130 ** on the destination file. ^The exclusive lock is not released until either 7131 ** sqlite3_backup_finish() is called or the backup operation is complete 7132 ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to 7133 ** sqlite3_backup_step() obtains a [shared lock] on the source database that 7134 ** lasts for the duration of the sqlite3_backup_step() call. 7135 ** ^Because the source database is not locked between calls to 7136 ** sqlite3_backup_step(), the source database may be modified mid-way 7137 ** through the backup process. ^If the source database is modified by an 7138 ** external process or via a database connection other than the one being 7139 ** used by the backup operation, then the backup will be automatically 7140 ** restarted by the next call to sqlite3_backup_step(). ^If the source 7141 ** database is modified by the using the same database connection as is used 7142 ** by the backup operation, then the backup database is automatically 7143 ** updated at the same time. 7144 ** 7145 ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> 7146 ** 7147 ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 7148 ** application wishes to abandon the backup operation, the application 7149 ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). 7150 ** ^The sqlite3_backup_finish() interfaces releases all 7151 ** resources associated with the [sqlite3_backup] object. 7152 ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any 7153 ** active write-transaction on the destination database is rolled back. 7154 ** The [sqlite3_backup] object is invalid 7155 ** and may not be used following a call to sqlite3_backup_finish(). 7156 ** 7157 ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no 7158 ** sqlite3_backup_step() errors occurred, regardless or whether or not 7159 ** sqlite3_backup_step() completed. 7160 ** ^If an out-of-memory condition or IO error occurred during any prior 7161 ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then 7162 ** sqlite3_backup_finish() returns the corresponding [error code]. 7163 ** 7164 ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() 7165 ** is not a permanent error and does not affect the return value of 7166 ** sqlite3_backup_finish(). 7167 ** 7168 ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] 7169 ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> 7170 ** 7171 ** ^The sqlite3_backup_remaining() routine returns the number of pages still 7172 ** to be backed up at the conclusion of the most recent sqlite3_backup_step(). 7173 ** ^The sqlite3_backup_pagecount() routine returns the total number of pages 7174 ** in the source database at the conclusion of the most recent 7175 ** sqlite3_backup_step(). 7176 ** ^(The values returned by these functions are only updated by 7177 ** sqlite3_backup_step(). If the source database is modified in a way that 7178 ** changes the size of the source database or the number of pages remaining, 7179 ** those changes are not reflected in the output of sqlite3_backup_pagecount() 7180 ** and sqlite3_backup_remaining() until after the next 7181 ** sqlite3_backup_step().)^ 7182 ** 7183 ** <b>Concurrent Usage of Database Handles</b> 7184 ** 7185 ** ^The source [database connection] may be used by the application for other 7186 ** purposes while a backup operation is underway or being initialized. 7187 ** ^If SQLite is compiled and configured to support threadsafe database 7188 ** connections, then the source database connection may be used concurrently 7189 ** from within other threads. 7190 ** 7191 ** However, the application must guarantee that the destination 7192 ** [database connection] is not passed to any other API (by any thread) after 7193 ** sqlite3_backup_init() is called and before the corresponding call to 7194 ** sqlite3_backup_finish(). SQLite does not currently check to see 7195 ** if the application incorrectly accesses the destination [database connection] 7196 ** and so no error code is reported, but the operations may malfunction 7197 ** nevertheless. Use of the destination database connection while a 7198 ** backup is in progress might also also cause a mutex deadlock. 7199 ** 7200 ** If running in [shared cache mode], the application must 7201 ** guarantee that the shared cache used by the destination database 7202 ** is not accessed while the backup is running. In practice this means 7203 ** that the application must guarantee that the disk file being 7204 ** backed up to is not accessed by any connection within the process, 7205 ** not just the specific connection that was passed to sqlite3_backup_init(). 7206 ** 7207 ** The [sqlite3_backup] object itself is partially threadsafe. Multiple 7208 ** threads may safely make multiple concurrent calls to sqlite3_backup_step(). 7209 ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() 7210 ** APIs are not strictly speaking threadsafe. If they are invoked at the 7211 ** same time as another thread is invoking sqlite3_backup_step() it is 7212 ** possible that they return invalid values. 7213 */ 7214 SQLITE_API sqlite3_backup *SQLITE_STDCALL sqlite3_backup_init( 7215 sqlite3 *pDest, /* Destination database handle */ 7216 const char *zDestName, /* Destination database name */ 7217 sqlite3 *pSource, /* Source database handle */ 7218 const char *zSourceName /* Source database name */ 7219 ); 7220 SQLITE_API int SQLITE_STDCALL sqlite3_backup_step(sqlite3_backup *p, int nPage); 7221 SQLITE_API int SQLITE_STDCALL sqlite3_backup_finish(sqlite3_backup *p); 7222 SQLITE_API int SQLITE_STDCALL sqlite3_backup_remaining(sqlite3_backup *p); 7223 SQLITE_API int SQLITE_STDCALL sqlite3_backup_pagecount(sqlite3_backup *p); 7224 7225 /* 7226 ** CAPI3REF: Unlock Notification 7227 ** METHOD: sqlite3 7228 ** 7229 ** ^When running in shared-cache mode, a database operation may fail with 7230 ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or 7231 ** individual tables within the shared-cache cannot be obtained. See 7232 ** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 7233 ** ^This API may be used to register a callback that SQLite will invoke 7234 ** when the connection currently holding the required lock relinquishes it. 7235 ** ^This API is only available if the library was compiled with the 7236 ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. 7237 ** 7238 ** See Also: [Using the SQLite Unlock Notification Feature]. 7239 ** 7240 ** ^Shared-cache locks are released when a database connection concludes 7241 ** its current transaction, either by committing it or rolling it back. 7242 ** 7243 ** ^When a connection (known as the blocked connection) fails to obtain a 7244 ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the 7245 ** identity of the database connection (the blocking connection) that 7246 ** has locked the required resource is stored internally. ^After an 7247 ** application receives an SQLITE_LOCKED error, it may call the 7248 ** sqlite3_unlock_notify() method with the blocked connection handle as 7249 ** the first argument to register for a callback that will be invoked 7250 ** when the blocking connections current transaction is concluded. ^The 7251 ** callback is invoked from within the [sqlite3_step] or [sqlite3_close] 7252 ** call that concludes the blocking connections transaction. 7253 ** 7254 ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, 7255 ** there is a chance that the blocking connection will have already 7256 ** concluded its transaction by the time sqlite3_unlock_notify() is invoked. 7257 ** If this happens, then the specified callback is invoked immediately, 7258 ** from within the call to sqlite3_unlock_notify().)^ 7259 ** 7260 ** ^If the blocked connection is attempting to obtain a write-lock on a 7261 ** shared-cache table, and more than one other connection currently holds 7262 ** a read-lock on the same table, then SQLite arbitrarily selects one of 7263 ** the other connections to use as the blocking connection. 7264 ** 7265 ** ^(There may be at most one unlock-notify callback registered by a 7266 ** blocked connection. If sqlite3_unlock_notify() is called when the 7267 ** blocked connection already has a registered unlock-notify callback, 7268 ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is 7269 ** called with a NULL pointer as its second argument, then any existing 7270 ** unlock-notify callback is canceled. ^The blocked connections 7271 ** unlock-notify callback may also be canceled by closing the blocked 7272 ** connection using [sqlite3_close()]. 7273 ** 7274 ** The unlock-notify callback is not reentrant. If an application invokes 7275 ** any sqlite3_xxx API functions from within an unlock-notify callback, a 7276 ** crash or deadlock may be the result. 7277 ** 7278 ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always 7279 ** returns SQLITE_OK. 7280 ** 7281 ** <b>Callback Invocation Details</b> 7282 ** 7283 ** When an unlock-notify callback is registered, the application provides a 7284 ** single void* pointer that is passed to the callback when it is invoked. 7285 ** However, the signature of the callback function allows SQLite to pass 7286 ** it an array of void* context pointers. The first argument passed to 7287 ** an unlock-notify callback is a pointer to an array of void* pointers, 7288 ** and the second is the number of entries in the array. 7289 ** 7290 ** When a blocking connections transaction is concluded, there may be 7291 ** more than one blocked connection that has registered for an unlock-notify 7292 ** callback. ^If two or more such blocked connections have specified the 7293 ** same callback function, then instead of invoking the callback function 7294 ** multiple times, it is invoked once with the set of void* context pointers 7295 ** specified by the blocked connections bundled together into an array. 7296 ** This gives the application an opportunity to prioritize any actions 7297 ** related to the set of unblocked database connections. 7298 ** 7299 ** <b>Deadlock Detection</b> 7300 ** 7301 ** Assuming that after registering for an unlock-notify callback a 7302 ** database waits for the callback to be issued before taking any further 7303 ** action (a reasonable assumption), then using this API may cause the 7304 ** application to deadlock. For example, if connection X is waiting for 7305 ** connection Y's transaction to be concluded, and similarly connection 7306 ** Y is waiting on connection X's transaction, then neither connection 7307 ** will proceed and the system may remain deadlocked indefinitely. 7308 ** 7309 ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock 7310 ** detection. ^If a given call to sqlite3_unlock_notify() would put the 7311 ** system in a deadlocked state, then SQLITE_LOCKED is returned and no 7312 ** unlock-notify callback is registered. The system is said to be in 7313 ** a deadlocked state if connection A has registered for an unlock-notify 7314 ** callback on the conclusion of connection B's transaction, and connection 7315 ** B has itself registered for an unlock-notify callback when connection 7316 ** A's transaction is concluded. ^Indirect deadlock is also detected, so 7317 ** the system is also considered to be deadlocked if connection B has 7318 ** registered for an unlock-notify callback on the conclusion of connection 7319 ** C's transaction, where connection C is waiting on connection A. ^Any 7320 ** number of levels of indirection are allowed. 7321 ** 7322 ** <b>The "DROP TABLE" Exception</b> 7323 ** 7324 ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 7325 ** always appropriate to call sqlite3_unlock_notify(). There is however, 7326 ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, 7327 ** SQLite checks if there are any currently executing SELECT statements 7328 ** that belong to the same connection. If there are, SQLITE_LOCKED is 7329 ** returned. In this case there is no "blocking connection", so invoking 7330 ** sqlite3_unlock_notify() results in the unlock-notify callback being 7331 ** invoked immediately. If the application then re-attempts the "DROP TABLE" 7332 ** or "DROP INDEX" query, an infinite loop might be the result. 7333 ** 7334 ** One way around this problem is to check the extended error code returned 7335 ** by an sqlite3_step() call. ^(If there is a blocking connection, then the 7336 ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in 7337 ** the special "DROP TABLE/INDEX" case, the extended error code is just 7338 ** SQLITE_LOCKED.)^ 7339 */ 7340 SQLITE_API int SQLITE_STDCALL sqlite3_unlock_notify( 7341 sqlite3 *pBlocked, /* Waiting connection */ 7342 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ 7343 void *pNotifyArg /* Argument to pass to xNotify */ 7344 ); 7345 7346 7347 /* 7348 ** CAPI3REF: String Comparison 7349 ** 7350 ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications 7351 ** and extensions to compare the contents of two buffers containing UTF-8 7352 ** strings in a case-independent fashion, using the same definition of "case 7353 ** independence" that SQLite uses internally when comparing identifiers. 7354 */ 7355 SQLITE_API int SQLITE_STDCALL sqlite3_stricmp(const char *, const char *); 7356 SQLITE_API int SQLITE_STDCALL sqlite3_strnicmp(const char *, const char *, int); 7357 7358 /* 7359 ** CAPI3REF: String Globbing 7360 * 7361 ** ^The [sqlite3_strglob(P,X)] interface returns zero if string X matches 7362 ** the glob pattern P, and it returns non-zero if string X does not match 7363 ** the glob pattern P. ^The definition of glob pattern matching used in 7364 ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the 7365 ** SQL dialect used by SQLite. ^The sqlite3_strglob(P,X) function is case 7366 ** sensitive. 7367 ** 7368 ** Note that this routine returns zero on a match and non-zero if the strings 7369 ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 7370 */ 7371 SQLITE_API int SQLITE_STDCALL sqlite3_strglob(const char *zGlob, const char *zStr); 7372 7373 /* 7374 ** CAPI3REF: Error Logging Interface 7375 ** 7376 ** ^The [sqlite3_log()] interface writes a message into the [error log] 7377 ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. 7378 ** ^If logging is enabled, the zFormat string and subsequent arguments are 7379 ** used with [sqlite3_snprintf()] to generate the final output string. 7380 ** 7381 ** The sqlite3_log() interface is intended for use by extensions such as 7382 ** virtual tables, collating functions, and SQL functions. While there is 7383 ** nothing to prevent an application from calling sqlite3_log(), doing so 7384 ** is considered bad form. 7385 ** 7386 ** The zFormat string must not be NULL. 7387 ** 7388 ** To avoid deadlocks and other threading problems, the sqlite3_log() routine 7389 ** will not use dynamically allocated memory. The log message is stored in 7390 ** a fixed-length buffer on the stack. If the log message is longer than 7391 ** a few hundred characters, it will be truncated to the length of the 7392 ** buffer. 7393 */ 7394 SQLITE_API void SQLITE_CDECL sqlite3_log(int iErrCode, const char *zFormat, ...); 7395 7396 /* 7397 ** CAPI3REF: Write-Ahead Log Commit Hook 7398 ** METHOD: sqlite3 7399 ** 7400 ** ^The [sqlite3_wal_hook()] function is used to register a callback that 7401 ** is invoked each time data is committed to a database in wal mode. 7402 ** 7403 ** ^(The callback is invoked by SQLite after the commit has taken place and 7404 ** the associated write-lock on the database released)^, so the implementation 7405 ** may read, write or [checkpoint] the database as required. 7406 ** 7407 ** ^The first parameter passed to the callback function when it is invoked 7408 ** is a copy of the third parameter passed to sqlite3_wal_hook() when 7409 ** registering the callback. ^The second is a copy of the database handle. 7410 ** ^The third parameter is the name of the database that was written to - 7411 ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter 7412 ** is the number of pages currently in the write-ahead log file, 7413 ** including those that were just committed. 7414 ** 7415 ** The callback function should normally return [SQLITE_OK]. ^If an error 7416 ** code is returned, that error will propagate back up through the 7417 ** SQLite code base to cause the statement that provoked the callback 7418 ** to report an error, though the commit will have still occurred. If the 7419 ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value 7420 ** that does not correspond to any valid SQLite error code, the results 7421 ** are undefined. 7422 ** 7423 ** A single database handle may have at most a single write-ahead log callback 7424 ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any 7425 ** previously registered write-ahead log callback. ^Note that the 7426 ** [sqlite3_wal_autocheckpoint()] interface and the 7427 ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will 7428 ** those overwrite any prior [sqlite3_wal_hook()] settings. 7429 */ 7430 SQLITE_API void *SQLITE_STDCALL sqlite3_wal_hook( 7431 sqlite3*, 7432 int(*)(void *,sqlite3*,const char*,int), 7433 void* 7434 ); 7435 7436 /* 7437 ** CAPI3REF: Configure an auto-checkpoint 7438 ** METHOD: sqlite3 7439 ** 7440 ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around 7441 ** [sqlite3_wal_hook()] that causes any database on [database connection] D 7442 ** to automatically [checkpoint] 7443 ** after committing a transaction if there are N or 7444 ** more frames in the [write-ahead log] file. ^Passing zero or 7445 ** a negative value as the nFrame parameter disables automatic 7446 ** checkpoints entirely. 7447 ** 7448 ** ^The callback registered by this function replaces any existing callback 7449 ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback 7450 ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism 7451 ** configured by this function. 7452 ** 7453 ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface 7454 ** from SQL. 7455 ** 7456 ** ^Checkpoints initiated by this mechanism are 7457 ** [sqlite3_wal_checkpoint_v2|PASSIVE]. 7458 ** 7459 ** ^Every new [database connection] defaults to having the auto-checkpoint 7460 ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] 7461 ** pages. The use of this interface 7462 ** is only necessary if the default setting is found to be suboptimal 7463 ** for a particular application. 7464 */ 7465 SQLITE_API int SQLITE_STDCALL sqlite3_wal_autocheckpoint(sqlite3 *db, int N); 7466 7467 /* 7468 ** CAPI3REF: Checkpoint a database 7469 ** METHOD: sqlite3 7470 ** 7471 ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to 7472 ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ 7473 ** 7474 ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the 7475 ** [write-ahead log] for database X on [database connection] D to be 7476 ** transferred into the database file and for the write-ahead log to 7477 ** be reset. See the [checkpointing] documentation for addition 7478 ** information. 7479 ** 7480 ** This interface used to be the only way to cause a checkpoint to 7481 ** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] 7482 ** interface was added. This interface is retained for backwards 7483 ** compatibility and as a convenience for applications that need to manually 7484 ** start a callback but which do not need the full power (and corresponding 7485 ** complication) of [sqlite3_wal_checkpoint_v2()]. 7486 */ 7487 SQLITE_API int SQLITE_STDCALL sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); 7488 7489 /* 7490 ** CAPI3REF: Checkpoint a database 7491 ** METHOD: sqlite3 7492 ** 7493 ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint 7494 ** operation on database X of [database connection] D in mode M. Status 7495 ** information is written back into integers pointed to by L and C.)^ 7496 ** ^(The M parameter must be a valid [checkpoint mode]:)^ 7497 ** 7498 ** <dl> 7499 ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> 7500 ** ^Checkpoint as many frames as possible without waiting for any database 7501 ** readers or writers to finish, then sync the database file if all frames 7502 ** in the log were checkpointed. ^The [busy-handler callback] 7503 ** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. 7504 ** ^On the other hand, passive mode might leave the checkpoint unfinished 7505 ** if there are concurrent readers or writers. 7506 ** 7507 ** <dt>SQLITE_CHECKPOINT_FULL<dd> 7508 ** ^This mode blocks (it invokes the 7509 ** [sqlite3_busy_handler|busy-handler callback]) until there is no 7510 ** database writer and all readers are reading from the most recent database 7511 ** snapshot. ^It then checkpoints all frames in the log file and syncs the 7512 ** database file. ^This mode blocks new database writers while it is pending, 7513 ** but new database readers are allowed to continue unimpeded. 7514 ** 7515 ** <dt>SQLITE_CHECKPOINT_RESTART<dd> 7516 ** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition 7517 ** that after checkpointing the log file it blocks (calls the 7518 ** [busy-handler callback]) 7519 ** until all readers are reading from the database file only. ^This ensures 7520 ** that the next writer will restart the log file from the beginning. 7521 ** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new 7522 ** database writer attempts while it is pending, but does not impede readers. 7523 ** 7524 ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> 7525 ** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the 7526 ** addition that it also truncates the log file to zero bytes just prior 7527 ** to a successful return. 7528 ** </dl> 7529 ** 7530 ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in 7531 ** the log file or to -1 if the checkpoint could not run because 7532 ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not 7533 ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the 7534 ** log file (including any that were already checkpointed before the function 7535 ** was called) or to -1 if the checkpoint could not run due to an error or 7536 ** because the database is not in WAL mode. ^Note that upon successful 7537 ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been 7538 ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. 7539 ** 7540 ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If 7541 ** any other process is running a checkpoint operation at the same time, the 7542 ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a 7543 ** busy-handler configured, it will not be invoked in this case. 7544 ** 7545 ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the 7546 ** exclusive "writer" lock on the database file. ^If the writer lock cannot be 7547 ** obtained immediately, and a busy-handler is configured, it is invoked and 7548 ** the writer lock retried until either the busy-handler returns 0 or the lock 7549 ** is successfully obtained. ^The busy-handler is also invoked while waiting for 7550 ** database readers as described above. ^If the busy-handler returns 0 before 7551 ** the writer lock is obtained or while waiting for database readers, the 7552 ** checkpoint operation proceeds from that point in the same way as 7553 ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible 7554 ** without blocking any further. ^SQLITE_BUSY is returned in this case. 7555 ** 7556 ** ^If parameter zDb is NULL or points to a zero length string, then the 7557 ** specified operation is attempted on all WAL databases [attached] to 7558 ** [database connection] db. In this case the 7559 ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If 7560 ** an SQLITE_BUSY error is encountered when processing one or more of the 7561 ** attached WAL databases, the operation is still attempted on any remaining 7562 ** attached databases and SQLITE_BUSY is returned at the end. ^If any other 7563 ** error occurs while processing an attached database, processing is abandoned 7564 ** and the error code is returned to the caller immediately. ^If no error 7565 ** (SQLITE_BUSY or otherwise) is encountered while processing the attached 7566 ** databases, SQLITE_OK is returned. 7567 ** 7568 ** ^If database zDb is the name of an attached database that is not in WAL 7569 ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If 7570 ** zDb is not NULL (or a zero length string) and is not the name of any 7571 ** attached database, SQLITE_ERROR is returned to the caller. 7572 ** 7573 ** ^Unless it returns SQLITE_MISUSE, 7574 ** the sqlite3_wal_checkpoint_v2() interface 7575 ** sets the error information that is queried by 7576 ** [sqlite3_errcode()] and [sqlite3_errmsg()]. 7577 ** 7578 ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface 7579 ** from SQL. 7580 */ 7581 SQLITE_API int SQLITE_STDCALL sqlite3_wal_checkpoint_v2( 7582 sqlite3 *db, /* Database handle */ 7583 const char *zDb, /* Name of attached database (or NULL) */ 7584 int eMode, /* SQLITE_CHECKPOINT_* value */ 7585 int *pnLog, /* OUT: Size of WAL log in frames */ 7586 int *pnCkpt /* OUT: Total number of frames checkpointed */ 7587 ); 7588 7589 /* 7590 ** CAPI3REF: Checkpoint Mode Values 7591 ** KEYWORDS: {checkpoint mode} 7592 ** 7593 ** These constants define all valid values for the "checkpoint mode" passed 7594 ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. 7595 ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the 7596 ** meaning of each of these checkpoint modes. 7597 */ 7598 #define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ 7599 #define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ 7600 #define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */ 7601 #define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ 7602 7603 /* 7604 ** CAPI3REF: Virtual Table Interface Configuration 7605 ** 7606 ** This function may be called by either the [xConnect] or [xCreate] method 7607 ** of a [virtual table] implementation to configure 7608 ** various facets of the virtual table interface. 7609 ** 7610 ** If this interface is invoked outside the context of an xConnect or 7611 ** xCreate virtual table method then the behavior is undefined. 7612 ** 7613 ** At present, there is only one option that may be configured using 7614 ** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options 7615 ** may be added in the future. 7616 */ 7617 SQLITE_API int SQLITE_CDECL sqlite3_vtab_config(sqlite3*, int op, ...); 7618 7619 /* 7620 ** CAPI3REF: Virtual Table Configuration Options 7621 ** 7622 ** These macros define the various options to the 7623 ** [sqlite3_vtab_config()] interface that [virtual table] implementations 7624 ** can use to customize and optimize their behavior. 7625 ** 7626 ** <dl> 7627 ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT 7628 ** <dd>Calls of the form 7629 ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, 7630 ** where X is an integer. If X is zero, then the [virtual table] whose 7631 ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not 7632 ** support constraints. In this configuration (which is the default) if 7633 ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire 7634 ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been 7635 ** specified as part of the users SQL statement, regardless of the actual 7636 ** ON CONFLICT mode specified. 7637 ** 7638 ** If X is non-zero, then the virtual table implementation guarantees 7639 ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before 7640 ** any modifications to internal or persistent data structures have been made. 7641 ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite 7642 ** is able to roll back a statement or database transaction, and abandon 7643 ** or continue processing the current SQL statement as appropriate. 7644 ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns 7645 ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode 7646 ** had been ABORT. 7647 ** 7648 ** Virtual table implementations that are required to handle OR REPLACE 7649 ** must do so within the [xUpdate] method. If a call to the 7650 ** [sqlite3_vtab_on_conflict()] function indicates that the current ON 7651 ** CONFLICT policy is REPLACE, the virtual table implementation should 7652 ** silently replace the appropriate rows within the xUpdate callback and 7653 ** return SQLITE_OK. Or, if this is not possible, it may return 7654 ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT 7655 ** constraint handling. 7656 ** </dl> 7657 */ 7658 #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 7659 7660 /* 7661 ** CAPI3REF: Determine The Virtual Table Conflict Policy 7662 ** 7663 ** This function may only be called from within a call to the [xUpdate] method 7664 ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The 7665 ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], 7666 ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode 7667 ** of the SQL statement that triggered the call to the [xUpdate] method of the 7668 ** [virtual table]. 7669 */ 7670 SQLITE_API int SQLITE_STDCALL sqlite3_vtab_on_conflict(sqlite3 *); 7671 7672 /* 7673 ** CAPI3REF: Conflict resolution modes 7674 ** KEYWORDS: {conflict resolution mode} 7675 ** 7676 ** These constants are returned by [sqlite3_vtab_on_conflict()] to 7677 ** inform a [virtual table] implementation what the [ON CONFLICT] mode 7678 ** is for the SQL statement being evaluated. 7679 ** 7680 ** Note that the [SQLITE_IGNORE] constant is also used as a potential 7681 ** return value from the [sqlite3_set_authorizer()] callback and that 7682 ** [SQLITE_ABORT] is also a [result code]. 7683 */ 7684 #define SQLITE_ROLLBACK 1 7685 /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ 7686 #define SQLITE_FAIL 3 7687 /* #define SQLITE_ABORT 4 // Also an error code */ 7688 #define SQLITE_REPLACE 5 7689 7690 /* 7691 ** CAPI3REF: Prepared Statement Scan Status Opcodes 7692 ** KEYWORDS: {scanstatus options} 7693 ** 7694 ** The following constants can be used for the T parameter to the 7695 ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a 7696 ** different metric for sqlite3_stmt_scanstatus() to return. 7697 ** 7698 ** When the value returned to V is a string, space to hold that string is 7699 ** managed by the prepared statement S and will be automatically freed when 7700 ** S is finalized. 7701 ** 7702 ** <dl> 7703 ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> 7704 ** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be 7705 ** set to the total number of times that the X-th loop has run.</dd> 7706 ** 7707 ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> 7708 ** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be set 7709 ** to the total number of rows examined by all iterations of the X-th loop.</dd> 7710 ** 7711 ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> 7712 ** <dd>^The "double" variable pointed to by the T parameter will be set to the 7713 ** query planner's estimate for the average number of rows output from each 7714 ** iteration of the X-th loop. If the query planner's estimates was accurate, 7715 ** then this value will approximate the quotient NVISIT/NLOOP and the 7716 ** product of this value for all prior loops with the same SELECTID will 7717 ** be the NLOOP value for the current loop. 7718 ** 7719 ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> 7720 ** <dd>^The "const char *" variable pointed to by the T parameter will be set 7721 ** to a zero-terminated UTF-8 string containing the name of the index or table 7722 ** used for the X-th loop. 7723 ** 7724 ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> 7725 ** <dd>^The "const char *" variable pointed to by the T parameter will be set 7726 ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] 7727 ** description for the X-th loop. 7728 ** 7729 ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt> 7730 ** <dd>^The "int" variable pointed to by the T parameter will be set to the 7731 ** "select-id" for the X-th loop. The select-id identifies which query or 7732 ** subquery the loop is part of. The main query has a select-id of zero. 7733 ** The select-id is the same value as is output in the first column 7734 ** of an [EXPLAIN QUERY PLAN] query. 7735 ** </dl> 7736 */ 7737 #define SQLITE_SCANSTAT_NLOOP 0 7738 #define SQLITE_SCANSTAT_NVISIT 1 7739 #define SQLITE_SCANSTAT_EST 2 7740 #define SQLITE_SCANSTAT_NAME 3 7741 #define SQLITE_SCANSTAT_EXPLAIN 4 7742 #define SQLITE_SCANSTAT_SELECTID 5 7743 7744 /* 7745 ** CAPI3REF: Prepared Statement Scan Status 7746 ** METHOD: sqlite3_stmt 7747 ** 7748 ** This interface returns information about the predicted and measured 7749 ** performance for pStmt. Advanced applications can use this 7750 ** interface to compare the predicted and the measured performance and 7751 ** issue warnings and/or rerun [ANALYZE] if discrepancies are found. 7752 ** 7753 ** Since this interface is expected to be rarely used, it is only 7754 ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] 7755 ** compile-time option. 7756 ** 7757 ** The "iScanStatusOp" parameter determines which status information to return. 7758 ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior 7759 ** of this interface is undefined. 7760 ** ^The requested measurement is written into a variable pointed to by 7761 ** the "pOut" parameter. 7762 ** Parameter "idx" identifies the specific loop to retrieve statistics for. 7763 ** Loops are numbered starting from zero. ^If idx is out of range - less than 7764 ** zero or greater than or equal to the total number of loops used to implement 7765 ** the statement - a non-zero value is returned and the variable that pOut 7766 ** points to is unchanged. 7767 ** 7768 ** ^Statistics might not be available for all loops in all statements. ^In cases 7769 ** where there exist loops with no available statistics, this function behaves 7770 ** as if the loop did not exist - it returns non-zero and leave the variable 7771 ** that pOut points to unchanged. 7772 ** 7773 ** See also: [sqlite3_stmt_scanstatus_reset()] 7774 */ 7775 SQLITE_API int SQLITE_STDCALL sqlite3_stmt_scanstatus( 7776 sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 7777 int idx, /* Index of loop to report on */ 7778 int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 7779 void *pOut /* Result written here */ 7780 ); 7781 7782 /* 7783 ** CAPI3REF: Zero Scan-Status Counters 7784 ** METHOD: sqlite3_stmt 7785 ** 7786 ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. 7787 ** 7788 ** This API is only available if the library is built with pre-processor 7789 ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. 7790 */ 7791 SQLITE_API void SQLITE_STDCALL sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); 7792 7793 7794 /* 7795 ** Undo the hack that converts floating point types to integer for 7796 ** builds on processors without floating point support. 7797 */ 7798 #ifdef SQLITE_OMIT_FLOATING_POINT 7799 # undef double 7800 #endif 7801 7802 #ifdef __cplusplus 7803 } /* End of the 'extern "C"' block */ 7804 #endif 7805 #endif /* _SQLITE3_H_ */ 7806 7807 /* 7808 ** 2010 August 30 7809 ** 7810 ** The author disclaims copyright to this source code. In place of 7811 ** a legal notice, here is a blessing: 7812 ** 7813 ** May you do good and not evil. 7814 ** May you find forgiveness for yourself and forgive others. 7815 ** May you share freely, never taking more than you give. 7816 ** 7817 ************************************************************************* 7818 */ 7819 7820 #ifndef _SQLITE3RTREE_H_ 7821 #define _SQLITE3RTREE_H_ 7822 7823 7824 #ifdef __cplusplus 7825 extern "C" { 7826 #endif 7827 7828 typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; 7829 typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; 7830 7831 /* The double-precision datatype used by RTree depends on the 7832 ** SQLITE_RTREE_INT_ONLY compile-time option. 7833 */ 7834 #ifdef SQLITE_RTREE_INT_ONLY 7835 typedef sqlite3_int64 sqlite3_rtree_dbl; 7836 #else 7837 typedef double sqlite3_rtree_dbl; 7838 #endif 7839 7840 /* 7841 ** Register a geometry callback named zGeom that can be used as part of an 7842 ** R-Tree geometry query as follows: 7843 ** 7844 ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...) 7845 */ 7846 SQLITE_API int SQLITE_STDCALL sqlite3_rtree_geometry_callback( 7847 sqlite3 *db, 7848 const char *zGeom, 7849 int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), 7850 void *pContext 7851 ); 7852 7853 7854 /* 7855 ** A pointer to a structure of the following type is passed as the first 7856 ** argument to callbacks registered using rtree_geometry_callback(). 7857 */ 7858 struct sqlite3_rtree_geometry { 7859 void *pContext; /* Copy of pContext passed to s_r_g_c() */ 7860 int nParam; /* Size of array aParam[] */ 7861 sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ 7862 void *pUser; /* Callback implementation user data */ 7863 void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ 7864 }; 7865 7866 /* 7867 ** Register a 2nd-generation geometry callback named zScore that can be 7868 ** used as part of an R-Tree geometry query as follows: 7869 ** 7870 ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...) 7871 */ 7872 SQLITE_API int SQLITE_STDCALL sqlite3_rtree_query_callback( 7873 sqlite3 *db, 7874 const char *zQueryFunc, 7875 int (*xQueryFunc)(sqlite3_rtree_query_info*), 7876 void *pContext, 7877 void (*xDestructor)(void*) 7878 ); 7879 7880 7881 /* 7882 ** A pointer to a structure of the following type is passed as the 7883 ** argument to scored geometry callback registered using 7884 ** sqlite3_rtree_query_callback(). 7885 ** 7886 ** Note that the first 5 fields of this structure are identical to 7887 ** sqlite3_rtree_geometry. This structure is a subclass of 7888 ** sqlite3_rtree_geometry. 7889 */ 7890 struct sqlite3_rtree_query_info { 7891 void *pContext; /* pContext from when function registered */ 7892 int nParam; /* Number of function parameters */ 7893 sqlite3_rtree_dbl *aParam; /* value of function parameters */ 7894 void *pUser; /* callback can use this, if desired */ 7895 void (*xDelUser)(void*); /* function to free pUser */ 7896 sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ 7897 unsigned int *anQueue; /* Number of pending entries in the queue */ 7898 int nCoord; /* Number of coordinates */ 7899 int iLevel; /* Level of current node or entry */ 7900 int mxLevel; /* The largest iLevel value in the tree */ 7901 sqlite3_int64 iRowid; /* Rowid for current entry */ 7902 sqlite3_rtree_dbl rParentScore; /* Score of parent node */ 7903 int eParentWithin; /* Visibility of parent node */ 7904 int eWithin; /* OUT: Visiblity */ 7905 sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ 7906 /* The following fields are only available in 3.8.11 and later */ 7907 sqlite3_value **apSqlParam; /* Original SQL values of parameters */ 7908 }; 7909 7910 /* 7911 ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. 7912 */ 7913 #define NOT_WITHIN 0 /* Object completely outside of query region */ 7914 #define PARTLY_WITHIN 1 /* Object partially overlaps query region */ 7915 #define FULLY_WITHIN 2 /* Object fully contained within query region */ 7916 7917 7918 #ifdef __cplusplus 7919 } /* end of the 'extern "C"' block */ 7920 #endif 7921 7922 #endif /* ifndef _SQLITE3RTREE_H_ */ 7923 7924 /* 7925 ** 2014 May 31 7926 ** 7927 ** The author disclaims copyright to this source code. In place of 7928 ** a legal notice, here is a blessing: 7929 ** 7930 ** May you do good and not evil. 7931 ** May you find forgiveness for yourself and forgive others. 7932 ** May you share freely, never taking more than you give. 7933 ** 7934 ****************************************************************************** 7935 ** 7936 ** Interfaces to extend FTS5. Using the interfaces defined in this file, 7937 ** FTS5 may be extended with: 7938 ** 7939 ** * custom tokenizers, and 7940 ** * custom auxiliary functions. 7941 */ 7942 7943 7944 #ifndef _FTS5_H 7945 #define _FTS5_H 7946 7947 7948 #ifdef __cplusplus 7949 extern "C" { 7950 #endif 7951 7952 /************************************************************************* 7953 ** CUSTOM AUXILIARY FUNCTIONS 7954 ** 7955 ** Virtual table implementations may overload SQL functions by implementing 7956 ** the sqlite3_module.xFindFunction() method. 7957 */ 7958 7959 typedef struct Fts5ExtensionApi Fts5ExtensionApi; 7960 typedef struct Fts5Context Fts5Context; 7961 typedef struct Fts5PhraseIter Fts5PhraseIter; 7962 7963 typedef void (*fts5_extension_function)( 7964 const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ 7965 Fts5Context *pFts, /* First arg to pass to pApi functions */ 7966 sqlite3_context *pCtx, /* Context for returning result/error */ 7967 int nVal, /* Number of values in apVal[] array */ 7968 sqlite3_value **apVal /* Array of trailing arguments */ 7969 ); 7970 7971 struct Fts5PhraseIter { 7972 const unsigned char *a; 7973 const unsigned char *b; 7974 }; 7975 7976 /* 7977 ** EXTENSION API FUNCTIONS 7978 ** 7979 ** xUserData(pFts): 7980 ** Return a copy of the context pointer the extension function was 7981 ** registered with. 7982 ** 7983 ** xColumnTotalSize(pFts, iCol, pnToken): 7984 ** If parameter iCol is less than zero, set output variable *pnToken 7985 ** to the total number of tokens in the FTS5 table. Or, if iCol is 7986 ** non-negative but less than the number of columns in the table, return 7987 ** the total number of tokens in column iCol, considering all rows in 7988 ** the FTS5 table. 7989 ** 7990 ** If parameter iCol is greater than or equal to the number of columns 7991 ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 7992 ** an OOM condition or IO error), an appropriate SQLite error code is 7993 ** returned. 7994 ** 7995 ** xColumnCount(pFts): 7996 ** Return the number of columns in the table. 7997 ** 7998 ** xColumnSize(pFts, iCol, pnToken): 7999 ** If parameter iCol is less than zero, set output variable *pnToken 8000 ** to the total number of tokens in the current row. Or, if iCol is 8001 ** non-negative but less than the number of columns in the table, set 8002 ** *pnToken to the number of tokens in column iCol of the current row. 8003 ** 8004 ** If parameter iCol is greater than or equal to the number of columns 8005 ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 8006 ** an OOM condition or IO error), an appropriate SQLite error code is 8007 ** returned. 8008 ** 8009 ** xColumnText: 8010 ** This function attempts to retrieve the text of column iCol of the 8011 ** current document. If successful, (*pz) is set to point to a buffer 8012 ** containing the text in utf-8 encoding, (*pn) is set to the size in bytes 8013 ** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, 8014 ** if an error occurs, an SQLite error code is returned and the final values 8015 ** of (*pz) and (*pn) are undefined. 8016 ** 8017 ** xPhraseCount: 8018 ** Returns the number of phrases in the current query expression. 8019 ** 8020 ** xPhraseSize: 8021 ** Returns the number of tokens in phrase iPhrase of the query. Phrases 8022 ** are numbered starting from zero. 8023 ** 8024 ** xInstCount: 8025 ** Set *pnInst to the total number of occurrences of all phrases within 8026 ** the query within the current row. Return SQLITE_OK if successful, or 8027 ** an error code (i.e. SQLITE_NOMEM) if an error occurs. 8028 ** 8029 ** xInst: 8030 ** Query for the details of phrase match iIdx within the current row. 8031 ** Phrase matches are numbered starting from zero, so the iIdx argument 8032 ** should be greater than or equal to zero and smaller than the value 8033 ** output by xInstCount(). 8034 ** 8035 ** Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM) 8036 ** if an error occurs. 8037 ** 8038 ** xRowid: 8039 ** Returns the rowid of the current row. 8040 ** 8041 ** xTokenize: 8042 ** Tokenize text using the tokenizer belonging to the FTS5 table. 8043 ** 8044 ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): 8045 ** This API function is used to query the FTS table for phrase iPhrase 8046 ** of the current query. Specifically, a query equivalent to: 8047 ** 8048 ** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid 8049 ** 8050 ** with $p set to a phrase equivalent to the phrase iPhrase of the 8051 ** current query is executed. For each row visited, the callback function 8052 ** passed as the fourth argument is invoked. The context and API objects 8053 ** passed to the callback function may be used to access the properties of 8054 ** each matched row. Invoking Api.xUserData() returns a copy of the pointer 8055 ** passed as the third argument to pUserData. 8056 ** 8057 ** If the callback function returns any value other than SQLITE_OK, the 8058 ** query is abandoned and the xQueryPhrase function returns immediately. 8059 ** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. 8060 ** Otherwise, the error code is propagated upwards. 8061 ** 8062 ** If the query runs to completion without incident, SQLITE_OK is returned. 8063 ** Or, if some error occurs before the query completes or is aborted by 8064 ** the callback, an SQLite error code is returned. 8065 ** 8066 ** 8067 ** xSetAuxdata(pFts5, pAux, xDelete) 8068 ** 8069 ** Save the pointer passed as the second argument as the extension functions 8070 ** "auxiliary data". The pointer may then be retrieved by the current or any 8071 ** future invocation of the same fts5 extension function made as part of 8072 ** of the same MATCH query using the xGetAuxdata() API. 8073 ** 8074 ** Each extension function is allocated a single auxiliary data slot for 8075 ** each FTS query (MATCH expression). If the extension function is invoked 8076 ** more than once for a single FTS query, then all invocations share a 8077 ** single auxiliary data context. 8078 ** 8079 ** If there is already an auxiliary data pointer when this function is 8080 ** invoked, then it is replaced by the new pointer. If an xDelete callback 8081 ** was specified along with the original pointer, it is invoked at this 8082 ** point. 8083 ** 8084 ** The xDelete callback, if one is specified, is also invoked on the 8085 ** auxiliary data pointer after the FTS5 query has finished. 8086 ** 8087 ** If an error (e.g. an OOM condition) occurs within this function, an 8088 ** the auxiliary data is set to NULL and an error code returned. If the 8089 ** xDelete parameter was not NULL, it is invoked on the auxiliary data 8090 ** pointer before returning. 8091 ** 8092 ** 8093 ** xGetAuxdata(pFts5, bClear) 8094 ** 8095 ** Returns the current auxiliary data pointer for the fts5 extension 8096 ** function. See the xSetAuxdata() method for details. 8097 ** 8098 ** If the bClear argument is non-zero, then the auxiliary data is cleared 8099 ** (set to NULL) before this function returns. In this case the xDelete, 8100 ** if any, is not invoked. 8101 ** 8102 ** 8103 ** xRowCount(pFts5, pnRow) 8104 ** 8105 ** This function is used to retrieve the total number of rows in the table. 8106 ** In other words, the same value that would be returned by: 8107 ** 8108 ** SELECT count(*) FROM ftstable; 8109 ** 8110 ** xPhraseFirst() 8111 ** This function is used, along with type Fts5PhraseIter and the xPhraseNext 8112 ** method, to iterate through all instances of a single query phrase within 8113 ** the current row. This is the same information as is accessible via the 8114 ** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient 8115 ** to use, this API may be faster under some circumstances. To iterate 8116 ** through instances of phrase iPhrase, use the following code: 8117 ** 8118 ** Fts5PhraseIter iter; 8119 ** int iCol, iOff; 8120 ** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); 8121 ** iOff>=0; 8122 ** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) 8123 ** ){ 8124 ** // An instance of phrase iPhrase at offset iOff of column iCol 8125 ** } 8126 ** 8127 ** The Fts5PhraseIter structure is defined above. Applications should not 8128 ** modify this structure directly - it should only be used as shown above 8129 ** with the xPhraseFirst() and xPhraseNext() API methods. 8130 ** 8131 ** xPhraseNext() 8132 ** See xPhraseFirst above. 8133 */ 8134 struct Fts5ExtensionApi { 8135 int iVersion; /* Currently always set to 1 */ 8136 8137 void *(*xUserData)(Fts5Context*); 8138 8139 int (*xColumnCount)(Fts5Context*); 8140 int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); 8141 int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); 8142 8143 int (*xTokenize)(Fts5Context*, 8144 const char *pText, int nText, /* Text to tokenize */ 8145 void *pCtx, /* Context passed to xToken() */ 8146 int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ 8147 ); 8148 8149 int (*xPhraseCount)(Fts5Context*); 8150 int (*xPhraseSize)(Fts5Context*, int iPhrase); 8151 8152 int (*xInstCount)(Fts5Context*, int *pnInst); 8153 int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); 8154 8155 sqlite3_int64 (*xRowid)(Fts5Context*); 8156 int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); 8157 int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); 8158 8159 int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, 8160 int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) 8161 ); 8162 int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); 8163 void *(*xGetAuxdata)(Fts5Context*, int bClear); 8164 8165 void (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); 8166 void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); 8167 }; 8168 8169 /* 8170 ** CUSTOM AUXILIARY FUNCTIONS 8171 *************************************************************************/ 8172 8173 /************************************************************************* 8174 ** CUSTOM TOKENIZERS 8175 ** 8176 ** Applications may also register custom tokenizer types. A tokenizer 8177 ** is registered by providing fts5 with a populated instance of the 8178 ** following structure. All structure methods must be defined, setting 8179 ** any member of the fts5_tokenizer struct to NULL leads to undefined 8180 ** behaviour. The structure methods are expected to function as follows: 8181 ** 8182 ** xCreate: 8183 ** This function is used to allocate and inititalize a tokenizer instance. 8184 ** A tokenizer instance is required to actually tokenize text. 8185 ** 8186 ** The first argument passed to this function is a copy of the (void*) 8187 ** pointer provided by the application when the fts5_tokenizer object 8188 ** was registered with FTS5 (the third argument to xCreateTokenizer()). 8189 ** The second and third arguments are an array of nul-terminated strings 8190 ** containing the tokenizer arguments, if any, specified following the 8191 ** tokenizer name as part of the CREATE VIRTUAL TABLE statement used 8192 ** to create the FTS5 table. 8193 ** 8194 ** The final argument is an output variable. If successful, (*ppOut) 8195 ** should be set to point to the new tokenizer handle and SQLITE_OK 8196 ** returned. If an error occurs, some value other than SQLITE_OK should 8197 ** be returned. In this case, fts5 assumes that the final value of *ppOut 8198 ** is undefined. 8199 ** 8200 ** xDelete: 8201 ** This function is invoked to delete a tokenizer handle previously 8202 ** allocated using xCreate(). Fts5 guarantees that this function will 8203 ** be invoked exactly once for each successful call to xCreate(). 8204 ** 8205 ** xTokenize: 8206 ** This function is expected to tokenize the nText byte string indicated 8207 ** by argument pText. pText may or may not be nul-terminated. The first 8208 ** argument passed to this function is a pointer to an Fts5Tokenizer object 8209 ** returned by an earlier call to xCreate(). 8210 ** 8211 ** The second argument indicates the reason that FTS5 is requesting 8212 ** tokenization of the supplied text. This is always one of the following 8213 ** four values: 8214 ** 8215 ** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into 8216 ** or removed from the FTS table. The tokenizer is being invoked to 8217 ** determine the set of tokens to add to (or delete from) the 8218 ** FTS index. 8219 ** 8220 ** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed 8221 ** against the FTS index. The tokenizer is being called to tokenize 8222 ** a bareword or quoted string specified as part of the query. 8223 ** 8224 ** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as 8225 ** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is 8226 ** followed by a "*" character, indicating that the last token 8227 ** returned by the tokenizer will be treated as a token prefix. 8228 ** 8229 ** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to 8230 ** satisfy an fts5_api.xTokenize() request made by an auxiliary 8231 ** function. Or an fts5_api.xColumnSize() request made by the same 8232 ** on a columnsize=0 database. 8233 ** </ul> 8234 ** 8235 ** For each token in the input string, the supplied callback xToken() must 8236 ** be invoked. The first argument to it should be a copy of the pointer 8237 ** passed as the second argument to xTokenize(). The third and fourth 8238 ** arguments are a pointer to a buffer containing the token text, and the 8239 ** size of the token in bytes. The 4th and 5th arguments are the byte offsets 8240 ** of the first byte of and first byte immediately following the text from 8241 ** which the token is derived within the input. 8242 ** 8243 ** The second argument passed to the xToken() callback ("tflags") should 8244 ** normally be set to 0. The exception is if the tokenizer supports 8245 ** synonyms. In this case see the discussion below for details. 8246 ** 8247 ** FTS5 assumes the xToken() callback is invoked for each token in the 8248 ** order that they occur within the input text. 8249 ** 8250 ** If an xToken() callback returns any value other than SQLITE_OK, then 8251 ** the tokenization should be abandoned and the xTokenize() method should 8252 ** immediately return a copy of the xToken() return value. Or, if the 8253 ** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, 8254 ** if an error occurs with the xTokenize() implementation itself, it 8255 ** may abandon the tokenization and return any error code other than 8256 ** SQLITE_OK or SQLITE_DONE. 8257 ** 8258 ** SYNONYM SUPPORT 8259 ** 8260 ** Custom tokenizers may also support synonyms. Consider a case in which a 8261 ** user wishes to query for a phrase such as "first place". Using the 8262 ** built-in tokenizers, the FTS5 query 'first + place' will match instances 8263 ** of "first place" within the document set, but not alternative forms 8264 ** such as "1st place". In some applications, it would be better to match 8265 ** all instances of "first place" or "1st place" regardless of which form 8266 ** the user specified in the MATCH query text. 8267 ** 8268 ** There are several ways to approach this in FTS5: 8269 ** 8270 ** <ol><li> By mapping all synonyms to a single token. In this case, the 8271 ** In the above example, this means that the tokenizer returns the 8272 ** same token for inputs "first" and "1st". Say that token is in 8273 ** fact "first", so that when the user inserts the document "I won 8274 ** 1st place" entries are added to the index for tokens "i", "won", 8275 ** "first" and "place". If the user then queries for '1st + place', 8276 ** the tokenizer substitutes "first" for "1st" and the query works 8277 ** as expected. 8278 ** 8279 ** <li> By adding multiple synonyms for a single term to the FTS index. 8280 ** In this case, when tokenizing query text, the tokenizer may 8281 ** provide multiple synonyms for a single term within the document. 8282 ** FTS5 then queries the index for each synonym individually. For 8283 ** example, faced with the query: 8284 ** 8285 ** <codeblock> 8286 ** ... MATCH 'first place'</codeblock> 8287 ** 8288 ** the tokenizer offers both "1st" and "first" as synonyms for the 8289 ** first token in the MATCH query and FTS5 effectively runs a query 8290 ** similar to: 8291 ** 8292 ** <codeblock> 8293 ** ... MATCH '(first OR 1st) place'</codeblock> 8294 ** 8295 ** except that, for the purposes of auxiliary functions, the query 8296 ** still appears to contain just two phrases - "(first OR 1st)" 8297 ** being treated as a single phrase. 8298 ** 8299 ** <li> By adding multiple synonyms for a single term to the FTS index. 8300 ** Using this method, when tokenizing document text, the tokenizer 8301 ** provides multiple synonyms for each token. So that when a 8302 ** document such as "I won first place" is tokenized, entries are 8303 ** added to the FTS index for "i", "won", "first", "1st" and 8304 ** "place". 8305 ** 8306 ** This way, even if the tokenizer does not provide synonyms 8307 ** when tokenizing query text (it should not - to do would be 8308 ** inefficient), it doesn't matter if the user queries for 8309 ** 'first + place' or '1st + place', as there are entires in the 8310 ** FTS index corresponding to both forms of the first token. 8311 ** </ol> 8312 ** 8313 ** Whether it is parsing document or query text, any call to xToken that 8314 ** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit 8315 ** is considered to supply a synonym for the previous token. For example, 8316 ** when parsing the document "I won first place", a tokenizer that supports 8317 ** synonyms would call xToken() 5 times, as follows: 8318 ** 8319 ** <codeblock> 8320 ** xToken(pCtx, 0, "i", 1, 0, 1); 8321 ** xToken(pCtx, 0, "won", 3, 2, 5); 8322 ** xToken(pCtx, 0, "first", 5, 6, 11); 8323 ** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); 8324 ** xToken(pCtx, 0, "place", 5, 12, 17); 8325 **</codeblock> 8326 ** 8327 ** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time 8328 ** xToken() is called. Multiple synonyms may be specified for a single token 8329 ** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. 8330 ** There is no limit to the number of synonyms that may be provided for a 8331 ** single token. 8332 ** 8333 ** In many cases, method (1) above is the best approach. It does not add 8334 ** extra data to the FTS index or require FTS5 to query for multiple terms, 8335 ** so it is efficient in terms of disk space and query speed. However, it 8336 ** does not support prefix queries very well. If, as suggested above, the 8337 ** token "first" is subsituted for "1st" by the tokenizer, then the query: 8338 ** 8339 ** <codeblock> 8340 ** ... MATCH '1s*'</codeblock> 8341 ** 8342 ** will not match documents that contain the token "1st" (as the tokenizer 8343 ** will probably not map "1s" to any prefix of "first"). 8344 ** 8345 ** For full prefix support, method (3) may be preferred. In this case, 8346 ** because the index contains entries for both "first" and "1st", prefix 8347 ** queries such as 'fi*' or '1s*' will match correctly. However, because 8348 ** extra entries are added to the FTS index, this method uses more space 8349 ** within the database. 8350 ** 8351 ** Method (2) offers a midpoint between (1) and (3). Using this method, 8352 ** a query such as '1s*' will match documents that contain the literal 8353 ** token "1st", but not "first" (assuming the tokenizer is not able to 8354 ** provide synonyms for prefixes). However, a non-prefix query like '1st' 8355 ** will match against "1st" and "first". This method does not require 8356 ** extra disk space, as no extra entries are added to the FTS index. 8357 ** On the other hand, it may require more CPU cycles to run MATCH queries, 8358 ** as separate queries of the FTS index are required for each synonym. 8359 ** 8360 ** When using methods (2) or (3), it is important that the tokenizer only 8361 ** provide synonyms when tokenizing document text (method (2)) or query 8362 ** text (method (3)), not both. Doing so will not cause any errors, but is 8363 ** inefficient. 8364 */ 8365 typedef struct Fts5Tokenizer Fts5Tokenizer; 8366 typedef struct fts5_tokenizer fts5_tokenizer; 8367 struct fts5_tokenizer { 8368 int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); 8369 void (*xDelete)(Fts5Tokenizer*); 8370 int (*xTokenize)(Fts5Tokenizer*, 8371 void *pCtx, 8372 int flags, /* Mask of FTS5_TOKENIZE_* flags */ 8373 const char *pText, int nText, 8374 int (*xToken)( 8375 void *pCtx, /* Copy of 2nd argument to xTokenize() */ 8376 int tflags, /* Mask of FTS5_TOKEN_* flags */ 8377 const char *pToken, /* Pointer to buffer containing token */ 8378 int nToken, /* Size of token in bytes */ 8379 int iStart, /* Byte offset of token within input text */ 8380 int iEnd /* Byte offset of end of token within input text */ 8381 ) 8382 ); 8383 }; 8384 8385 /* Flags that may be passed as the third argument to xTokenize() */ 8386 #define FTS5_TOKENIZE_QUERY 0x0001 8387 #define FTS5_TOKENIZE_PREFIX 0x0002 8388 #define FTS5_TOKENIZE_DOCUMENT 0x0004 8389 #define FTS5_TOKENIZE_AUX 0x0008 8390 8391 /* Flags that may be passed by the tokenizer implementation back to FTS5 8392 ** as the third argument to the supplied xToken callback. */ 8393 #define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ 8394 8395 /* 8396 ** END OF CUSTOM TOKENIZERS 8397 *************************************************************************/ 8398 8399 /************************************************************************* 8400 ** FTS5 EXTENSION REGISTRATION API 8401 */ 8402 typedef struct fts5_api fts5_api; 8403 struct fts5_api { 8404 int iVersion; /* Currently always set to 2 */ 8405 8406 /* Create a new tokenizer */ 8407 int (*xCreateTokenizer)( 8408 fts5_api *pApi, 8409 const char *zName, 8410 void *pContext, 8411 fts5_tokenizer *pTokenizer, 8412 void (*xDestroy)(void*) 8413 ); 8414 8415 /* Find an existing tokenizer */ 8416 int (*xFindTokenizer)( 8417 fts5_api *pApi, 8418 const char *zName, 8419 void **ppContext, 8420 fts5_tokenizer *pTokenizer 8421 ); 8422 8423 /* Create a new auxiliary function */ 8424 int (*xCreateFunction)( 8425 fts5_api *pApi, 8426 const char *zName, 8427 void *pContext, 8428 fts5_extension_function xFunction, 8429 void (*xDestroy)(void*) 8430 ); 8431 }; 8432 8433 /* 8434 ** END OF REGISTRATION API 8435 *************************************************************************/ 8436 8437 #ifdef __cplusplus 8438 } /* end of the 'extern "C"' block */ 8439 #endif 8440 8441 #endif /* _FTS5_H */ 8442 8443 8444
