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 to make minor changes if 22** experience from use "in the wild" suggest such changes are prudent. 23** 24** The official C-language API documentation for SQLite is derived 25** from comments in this file. This file is the authoritative source 26** on how SQLite interfaces are suppose to operate. 27** 28** The name of this file under configuration management is "sqlite.h.in". 29** The makefile makes some minor changes to this file (such as inserting 30** the version number) and changes its name to "sqlite3.h" as 31** part of the build process. 32** 33** @(#) $Id: sqlite.h.in,v 1.397 2008/09/02 21:35:03 drh Exp $ 34*/ 35#ifndef _SQLITE3_H_ 36#define _SQLITE3_H_ 37#include <stdarg.h> /* Needed for the definition of va_list */ 38 39/* 40** Make sure we can call this stuff from C++. 41*/ 42#ifdef __cplusplus 43extern "C" { 44#endif 45 46 47/* 48** Add the ability to override 'extern' 49*/ 50#ifndef SQLITE_EXTERN 51# define SQLITE_EXTERN extern 52#endif 53 54/* 55** Add the ability to mark interfaces as deprecated. 56*/ 57#if (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1)) 58 /* GCC added the deprecated attribute in version 3.1 */ 59 #define SQLITE_DEPRECATED __attribute__ ((deprecated)) 60#elif defined(_MSC_VER) && (_MSC_VER>1200) 61 #define SQLITE_DEPRECATED __declspec(deprecated) 62#else 63 #define SQLITE_DEPRECATED 64#endif 65 66/* 67** Add the ability to mark interfaces as experimental. 68*/ 69#if (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)) 70 /* I can confirm that it does not work on version 4.1.0... */ 71 /* First appears in GCC docs for version 4.3.0 */ 72 #define SQLITE_EXPERIMENTAL __attribute__ ((warning ("is experimental"))) 73#elif defined(_MSC_VER) && (_MSC_VER>1200) 74 #define SQLITE_EXPERIMENTAL __declspec(deprecated("was declared experimental")) 75#else 76 #define SQLITE_EXPERIMENTAL 77#endif 78 79/* 80** Ensure these symbols were not defined by some previous header file. 81*/ 82#ifdef SQLITE_VERSION 83# undef SQLITE_VERSION 84#endif 85#ifdef SQLITE_VERSION_NUMBER 86# undef SQLITE_VERSION_NUMBER 87#endif 88 89/* 90** CAPI3REF: Compile-Time Library Version Numbers {H10010} <S60100> 91** 92** The SQLITE_VERSION and SQLITE_VERSION_NUMBER #defines in 93** the sqlite3.h file specify the version of SQLite with which 94** that header file is associated. 95** 96** The "version" of SQLite is a string of the form "X.Y.Z". 97** The phrase "alpha" or "beta" might be appended after the Z. 98** The X value is major version number always 3 in SQLite3. 99** The X value only changes when backwards compatibility is 100** broken and we intend to never break backwards compatibility. 101** The Y value is the minor version number and only changes when 102** there are major feature enhancements that are forwards compatible 103** but not backwards compatible. 104** The Z value is the release number and is incremented with 105** each release but resets back to 0 whenever Y is incremented. 106** 107** See also: [sqlite3_libversion()] and [sqlite3_libversion_number()]. 108** 109** INVARIANTS: 110** 111** {H10011} The SQLITE_VERSION #define in the sqlite3.h header file shall 112** evaluate to a string literal that is the SQLite version 113** with which the header file is associated. 114** 115** {H10014} The SQLITE_VERSION_NUMBER #define shall resolve to an integer 116** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z 117** are the major version, minor version, and release number. 118*/ 119#define SQLITE_VERSION "--VERS--" 120#define SQLITE_VERSION_NUMBER --VERSION-NUMBER-- 121 122/* 123** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100> 124** KEYWORDS: sqlite3_version 125** 126** These features provide the same information as the [SQLITE_VERSION] 127** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated 128** with the library instead of the header file. Cautious programmers might 129** include a check in their application to verify that 130** sqlite3_libversion_number() always returns the value 131** [SQLITE_VERSION_NUMBER]. 132** 133** The sqlite3_libversion() function returns the same information as is 134** in the sqlite3_version[] string constant. The function is provided 135** for use in DLLs since DLL users usually do not have direct access to string 136** constants within the DLL. 137** 138** INVARIANTS: 139** 140** {H10021} The [sqlite3_libversion_number()] interface shall return 141** an integer equal to [SQLITE_VERSION_NUMBER]. 142** 143** {H10022} The [sqlite3_version] string constant shall contain 144** the text of the [SQLITE_VERSION] string. 145** 146** {H10023} The [sqlite3_libversion()] function shall return 147** a pointer to the [sqlite3_version] string constant. 148*/ 149SQLITE_EXTERN const char sqlite3_version[]; 150const char *sqlite3_libversion(void); 151int sqlite3_libversion_number(void); 152 153/* 154** CAPI3REF: Test To See If The Library Is Threadsafe {H10100} <S60100> 155** 156** SQLite can be compiled with or without mutexes. When 157** the [SQLITE_THREADSAFE] C preprocessor macro 1 or 2, mutexes 158** are enabled and SQLite is threadsafe. When the 159** [SQLITE_THREADSAFE] macro is 0, 160** the mutexes are omitted. Without the mutexes, it is not safe 161** to use SQLite concurrently from more than one thread. 162** 163** Enabling mutexes incurs a measurable performance penalty. 164** So if speed is of utmost importance, it makes sense to disable 165** the mutexes. But for maximum safety, mutexes should be enabled. 166** The default behavior is for mutexes to be enabled. 167** 168** This interface can be used by a program to make sure that the 169** version of SQLite that it is linking against was compiled with 170** the desired setting of the [SQLITE_THREADSAFE] macro. 171** 172** This interface only reports on the compile-time mutex setting 173** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with 174** SQLITE_THREADSAFE=1 then mutexes are enabled by default but 175** can be fully or partially disabled using a call to [sqlite3_config()] 176** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], 177** or [SQLITE_CONFIG_MUTEX]. The return value of this function shows 178** only the default compile-time setting, not any run-time changes 179** to that setting. 180** 181** See the [threading mode] documentation for additional information. 182** 183** INVARIANTS: 184** 185** {H10101} The [sqlite3_threadsafe()] function shall return nonzero if 186** and only if 187** SQLite was compiled with the its mutexes enabled by default. 188** 189** {H10102} The value returned by the [sqlite3_threadsafe()] function 190** shall not change when mutex setting are modified at 191** runtime using the [sqlite3_config()] interface and 192** especially the [SQLITE_CONFIG_SINGLETHREAD], 193** [SQLITE_CONFIG_MULTITHREAD], [SQLITE_CONFIG_SERIALIZED], 194** and [SQLITE_CONFIG_MUTEX] verbs. 195*/ 196int sqlite3_threadsafe(void); 197 198/* 199** CAPI3REF: Database Connection Handle {H12000} <S40200> 200** KEYWORDS: {database connection} {database connections} 201** 202** Each open SQLite database is represented by a pointer to an instance of 203** the opaque structure named "sqlite3". It is useful to think of an sqlite3 204** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and 205** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] 206** is its destructor. There are many other interfaces (such as 207** [sqlite3_prepare_v2()], [sqlite3_create_function()], and 208** [sqlite3_busy_timeout()] to name but three) that are methods on an 209** sqlite3 object. 210*/ 211typedef struct sqlite3 sqlite3; 212 213/* 214** CAPI3REF: 64-Bit Integer Types {H10200} <S10110> 215** KEYWORDS: sqlite_int64 sqlite_uint64 216** 217** Because there is no cross-platform way to specify 64-bit integer types 218** SQLite includes typedefs for 64-bit signed and unsigned integers. 219** 220** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. 221** The sqlite_int64 and sqlite_uint64 types are supported for backwards 222** compatibility only. 223** 224** INVARIANTS: 225** 226** {H10201} The [sqlite_int64] and [sqlite3_int64] type shall specify 227** a 64-bit signed integer. 228** 229** {H10202} The [sqlite_uint64] and [sqlite3_uint64] type shall specify 230** a 64-bit unsigned integer. 231*/ 232#ifdef SQLITE_INT64_TYPE 233 typedef SQLITE_INT64_TYPE sqlite_int64; 234 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; 235#elif defined(_MSC_VER) || defined(__BORLANDC__) 236 typedef __int64 sqlite_int64; 237 typedef unsigned __int64 sqlite_uint64; 238#else 239 typedef long long int sqlite_int64; 240 typedef unsigned long long int sqlite_uint64; 241#endif 242typedef sqlite_int64 sqlite3_int64; 243typedef sqlite_uint64 sqlite3_uint64; 244 245/* 246** If compiling for a processor that lacks floating point support, 247** substitute integer for floating-point. 248*/ 249#ifdef SQLITE_OMIT_FLOATING_POINT 250# define double sqlite3_int64 251#endif 252 253/* 254** CAPI3REF: Closing A Database Connection {H12010} <S30100><S40200> 255** 256** This routine is the destructor for the [sqlite3] object. 257** 258** Applications should [sqlite3_finalize | finalize] all [prepared statements] 259** and [sqlite3_blob_close | close] all [BLOB handles] associated with 260** the [sqlite3] object prior to attempting to close the object. 261** The [sqlite3_next_stmt()] interface can be used to locate all 262** [prepared statements] associated with a [database connection] if desired. 263** Typical code might look like this: 264** 265** <blockquote><pre> 266** sqlite3_stmt *pStmt; 267** while( (pStmt = sqlite3_next_stmt(db, 0))!=0 ){ 268** sqlite3_finalize(pStmt); 269** } 270** </pre></blockquote> 271** 272** If [sqlite3_close()] is invoked while a transaction is open, 273** the transaction is automatically rolled back. 274** 275** INVARIANTS: 276** 277** {H12011} A successful call to [sqlite3_close(C)] shall destroy the 278** [database connection] object C. 279** 280** {H12012} A successful call to [sqlite3_close(C)] shall return SQLITE_OK. 281** 282** {H12013} A successful call to [sqlite3_close(C)] shall release all 283** memory and system resources associated with [database connection] 284** C. 285** 286** {H12014} A call to [sqlite3_close(C)] on a [database connection] C that 287** has one or more open [prepared statements] shall fail with 288** an [SQLITE_BUSY] error code. 289** 290** {H12015} A call to [sqlite3_close(C)] where C is a NULL pointer shall 291** return SQLITE_OK. 292** 293** {H12019} When [sqlite3_close(C)] is invoked on a [database connection] C 294** that has a pending transaction, the transaction shall be 295** rolled back. 296** 297** ASSUMPTIONS: 298** 299** {A12016} The C parameter to [sqlite3_close(C)] must be either a NULL 300** pointer or an [sqlite3] object pointer obtained 301** from [sqlite3_open()], [sqlite3_open16()], or 302** [sqlite3_open_v2()], and not previously closed. 303*/ 304int sqlite3_close(sqlite3 *); 305 306/* 307** The type for a callback function. 308** This is legacy and deprecated. It is included for historical 309** compatibility and is not documented. 310*/ 311typedef int (*sqlite3_callback)(void*,int,char**, char**); 312 313/* 314** CAPI3REF: One-Step Query Execution Interface {H12100} <S10000> 315** 316** The sqlite3_exec() interface is a convenient way of running one or more 317** SQL statements without having to write a lot of C code. The UTF-8 encoded 318** SQL statements are passed in as the second parameter to sqlite3_exec(). 319** The statements are evaluated one by one until either an error or 320** an interrupt is encountered, or until they are all done. The 3rd parameter 321** is an optional callback that is invoked once for each row of any query 322** results produced by the SQL statements. The 5th parameter tells where 323** to write any error messages. 324** 325** The error message passed back through the 5th parameter is held 326** in memory obtained from [sqlite3_malloc()]. To avoid a memory leak, 327** the calling application should call [sqlite3_free()] on any error 328** message returned through the 5th parameter when it has finished using 329** the error message. 330** 331** If the SQL statement in the 2nd parameter is NULL or an empty string 332** or a string containing only whitespace and comments, then no SQL 333** statements are evaluated and the database is not changed. 334** 335** The sqlite3_exec() interface is implemented in terms of 336** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()]. 337** The sqlite3_exec() routine does nothing to the database that cannot be done 338** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()]. 339** 340** INVARIANTS: 341** 342** {H12101} A successful invocation of [sqlite3_exec(D,S,C,A,E)] 343** shall sequentially evaluate all of the UTF-8 encoded, 344** semicolon-separated SQL statements in the zero-terminated 345** string S within the context of the [database connection] D. 346** 347** {H12102} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL then 348** the actions of the interface shall be the same as if the 349** S parameter were an empty string. 350** 351** {H12104} The return value of [sqlite3_exec()] shall be [SQLITE_OK] if all 352** SQL statements run successfully and to completion. 353** 354** {H12105} The return value of [sqlite3_exec()] shall be an appropriate 355** non-zero [error code] if any SQL statement fails. 356** 357** {H12107} If one or more of the SQL statements handed to [sqlite3_exec()] 358** return results and the 3rd parameter is not NULL, then 359** the callback function specified by the 3rd parameter shall be 360** invoked once for each row of result. 361** 362** {H12110} If the callback returns a non-zero value then [sqlite3_exec()] 363** shall abort the SQL statement it is currently evaluating, 364** skip all subsequent SQL statements, and return [SQLITE_ABORT]. 365** 366** {H12113} The [sqlite3_exec()] routine shall pass its 4th parameter through 367** as the 1st parameter of the callback. 368** 369** {H12116} The [sqlite3_exec()] routine shall set the 2nd parameter of its 370** callback to be the number of columns in the current row of 371** result. 372** 373** {H12119} The [sqlite3_exec()] routine shall set the 3rd parameter of its 374** callback to be an array of pointers to strings holding the 375** values for each column in the current result set row as 376** obtained from [sqlite3_column_text()]. 377** 378** {H12122} The [sqlite3_exec()] routine shall set the 4th parameter of its 379** callback to be an array of pointers to strings holding the 380** names of result columns as obtained from [sqlite3_column_name()]. 381** 382** {H12125} If the 3rd parameter to [sqlite3_exec()] is NULL then 383** [sqlite3_exec()] shall silently discard query results. 384** 385** {H12131} If an error occurs while parsing or evaluating any of the SQL 386** statements in the S parameter of [sqlite3_exec(D,S,C,A,E)] and if 387** the E parameter is not NULL, then [sqlite3_exec()] shall store 388** in *E an appropriate error message written into memory obtained 389** from [sqlite3_malloc()]. 390** 391** {H12134} The [sqlite3_exec(D,S,C,A,E)] routine shall set the value of 392** *E to NULL if E is not NULL and there are no errors. 393** 394** {H12137} The [sqlite3_exec(D,S,C,A,E)] function shall set the [error code] 395** and message accessible via [sqlite3_errcode()], 396** [sqlite3_errmsg()], and [sqlite3_errmsg16()]. 397** 398** {H12138} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL or an 399** empty string or contains nothing other than whitespace, comments, 400** and/or semicolons, then results of [sqlite3_errcode()], 401** [sqlite3_errmsg()], and [sqlite3_errmsg16()] 402** shall reset to indicate no errors. 403** 404** ASSUMPTIONS: 405** 406** {A12141} The first parameter to [sqlite3_exec()] must be an valid and open 407** [database connection]. 408** 409** {A12142} The database connection must not be closed while 410** [sqlite3_exec()] is running. 411** 412** {A12143} The calling function should use [sqlite3_free()] to free 413** the memory that *errmsg is left pointing at once the error 414** message is no longer needed. 415** 416** {A12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()] 417** must remain unchanged while [sqlite3_exec()] is running. 418*/ 419int sqlite3_exec( 420 sqlite3*, /* An open database */ 421 const char *sql, /* SQL to be evaluated */ 422 int (*callback)(void*,int,char**,char**), /* Callback function */ 423 void *, /* 1st argument to callback */ 424 char **errmsg /* Error msg written here */ 425); 426 427/* 428** CAPI3REF: Result Codes {H10210} <S10700> 429** KEYWORDS: SQLITE_OK {error code} {error codes} 430** KEYWORDS: {result code} {result codes} 431** 432** Many SQLite functions return an integer result code from the set shown 433** here in order to indicates success or failure. 434** 435** New error codes may be added in future versions of SQLite. 436** 437** See also: [SQLITE_IOERR_READ | extended result codes] 438*/ 439#define SQLITE_OK 0 /* Successful result */ 440/* beginning-of-error-codes */ 441#define SQLITE_ERROR 1 /* SQL error or missing database */ 442#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ 443#define SQLITE_PERM 3 /* Access permission denied */ 444#define SQLITE_ABORT 4 /* Callback routine requested an abort */ 445#define SQLITE_BUSY 5 /* The database file is locked */ 446#define SQLITE_LOCKED 6 /* A table in the database is locked */ 447#define SQLITE_NOMEM 7 /* A malloc() failed */ 448#define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 449#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ 450#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 451#define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 452#define SQLITE_NOTFOUND 12 /* NOT USED. Table or record not found */ 453#define SQLITE_FULL 13 /* Insertion failed because database is full */ 454#define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 455#define SQLITE_PROTOCOL 15 /* NOT USED. Database lock protocol error */ 456#define SQLITE_EMPTY 16 /* Database is empty */ 457#define SQLITE_SCHEMA 17 /* The database schema changed */ 458#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ 459#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ 460#define SQLITE_MISMATCH 20 /* Data type mismatch */ 461#define SQLITE_MISUSE 21 /* Library used incorrectly */ 462#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 463#define SQLITE_AUTH 23 /* Authorization denied */ 464#define SQLITE_FORMAT 24 /* Auxiliary database format error */ 465#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ 466#define SQLITE_NOTADB 26 /* File opened that is not a database file */ 467#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ 468#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ 469/* end-of-error-codes */ 470 471/* 472** CAPI3REF: Extended Result Codes {H10220} <S10700> 473** KEYWORDS: {extended error code} {extended error codes} 474** KEYWORDS: {extended result code} {extended result codes} 475** 476** In its default configuration, SQLite API routines return one of 26 integer 477** [SQLITE_OK | result codes]. However, experience has shown that many of 478** these result codes are too coarse-grained. They do not provide as 479** much information about problems as programmers might like. In an effort to 480** address this, newer versions of SQLite (version 3.3.8 and later) include 481** support for additional result codes that provide more detailed information 482** about errors. The extended result codes are enabled or disabled 483** on a per database connection basis using the 484** [sqlite3_extended_result_codes()] API. 485** 486** Some of the available extended result codes are listed here. 487** One may expect the number of extended result codes will be expand 488** over time. Software that uses extended result codes should expect 489** to see new result codes in future releases of SQLite. 490** 491** The SQLITE_OK result code will never be extended. It will always 492** be exactly zero. 493** 494** INVARIANTS: 495** 496** {H10223} The symbolic name for an extended result code shall contains 497** a related primary result code as a prefix. 498** 499** {H10224} Primary result code names shall contain a single "_" character. 500** 501** {H10225} Extended result code names shall contain two or more "_" characters. 502** 503** {H10226} The numeric value of an extended result code shall contain the 504** numeric value of its corresponding primary result code in 505** its least significant 8 bits. 506*/ 507#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) 508#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) 509#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) 510#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) 511#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) 512#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) 513#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) 514#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) 515#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) 516#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) 517#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) 518#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) 519#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) 520#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) 521#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) 522 523/* 524** CAPI3REF: Flags For File Open Operations {H10230} <H11120> <H12700> 525** 526** These bit values are intended for use in the 527** 3rd parameter to the [sqlite3_open_v2()] interface and 528** in the 4th parameter to the xOpen method of the 529** [sqlite3_vfs] object. 530*/ 531#define SQLITE_OPEN_READONLY 0x00000001 532#define SQLITE_OPEN_READWRITE 0x00000002 533#define SQLITE_OPEN_CREATE 0x00000004 534#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 535#define SQLITE_OPEN_EXCLUSIVE 0x00000010 536#define SQLITE_OPEN_MAIN_DB 0x00000100 537#define SQLITE_OPEN_TEMP_DB 0x00000200 538#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 539#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 540#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 541#define SQLITE_OPEN_SUBJOURNAL 0x00002000 542#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 543#define SQLITE_OPEN_NOMUTEX 0x00008000 544#define SQLITE_OPEN_FULLMUTEX 0x00010000 545 546/* 547** CAPI3REF: Device Characteristics {H10240} <H11120> 548** 549** The xDeviceCapabilities method of the [sqlite3_io_methods] 550** object returns an integer which is a vector of the these 551** bit values expressing I/O characteristics of the mass storage 552** device that holds the file that the [sqlite3_io_methods] 553** refers to. 554** 555** The SQLITE_IOCAP_ATOMIC property means that all writes of 556** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 557** mean that writes of blocks that are nnn bytes in size and 558** are aligned to an address which is an integer multiple of 559** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 560** that when data is appended to a file, the data is appended 561** first then the size of the file is extended, never the other 562** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 563** information is written to disk in the same order as calls 564** to xWrite(). 565*/ 566#define SQLITE_IOCAP_ATOMIC 0x00000001 567#define SQLITE_IOCAP_ATOMIC512 0x00000002 568#define SQLITE_IOCAP_ATOMIC1K 0x00000004 569#define SQLITE_IOCAP_ATOMIC2K 0x00000008 570#define SQLITE_IOCAP_ATOMIC4K 0x00000010 571#define SQLITE_IOCAP_ATOMIC8K 0x00000020 572#define SQLITE_IOCAP_ATOMIC16K 0x00000040 573#define SQLITE_IOCAP_ATOMIC32K 0x00000080 574#define SQLITE_IOCAP_ATOMIC64K 0x00000100 575#define SQLITE_IOCAP_SAFE_APPEND 0x00000200 576#define SQLITE_IOCAP_SEQUENTIAL 0x00000400 577 578/* 579** CAPI3REF: File Locking Levels {H10250} <H11120> <H11310> 580** 581** SQLite uses one of these integer values as the second 582** argument to calls it makes to the xLock() and xUnlock() methods 583** of an [sqlite3_io_methods] object. 584*/ 585#define SQLITE_LOCK_NONE 0 586#define SQLITE_LOCK_SHARED 1 587#define SQLITE_LOCK_RESERVED 2 588#define SQLITE_LOCK_PENDING 3 589#define SQLITE_LOCK_EXCLUSIVE 4 590 591/* 592** CAPI3REF: Synchronization Type Flags {H10260} <H11120> 593** 594** When SQLite invokes the xSync() method of an 595** [sqlite3_io_methods] object it uses a combination of 596** these integer values as the second argument. 597** 598** When the SQLITE_SYNC_DATAONLY flag is used, it means that the 599** sync operation only needs to flush data to mass storage. Inode 600** information need not be flushed. The SQLITE_SYNC_NORMAL flag means 601** to use normal fsync() semantics. The SQLITE_SYNC_FULL flag means 602** to use Mac OS-X style fullsync instead of fsync(). 603*/ 604#define SQLITE_SYNC_NORMAL 0x00002 605#define SQLITE_SYNC_FULL 0x00003 606#define SQLITE_SYNC_DATAONLY 0x00010 607 608/* 609** CAPI3REF: OS Interface Open File Handle {H11110} <S20110> 610** 611** An [sqlite3_file] object represents an open file in the OS 612** interface layer. Individual OS interface implementations will 613** want to subclass this object by appending additional fields 614** for their own use. The pMethods entry is a pointer to an 615** [sqlite3_io_methods] object that defines methods for performing 616** I/O operations on the open file. 617*/ 618typedef struct sqlite3_file sqlite3_file; 619struct sqlite3_file { 620 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ 621}; 622 623/* 624** CAPI3REF: OS Interface File Virtual Methods Object {H11120} <S20110> 625** 626** Every file opened by the [sqlite3_vfs] xOpen method populates an 627** [sqlite3_file] object (or, more commonly, a subclass of the 628** [sqlite3_file] object) with a pointer to an instance of this object. 629** This object defines the methods used to perform various operations 630** against the open file represented by the [sqlite3_file] object. 631** 632** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or 633** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). 634** The second choice is a Mac OS-X style fullsync. The [SQLITE_SYNC_DATAONLY] 635** flag may be ORed in to indicate that only the data of the file 636** and not its inode needs to be synced. 637** 638** The integer values to xLock() and xUnlock() are one of 639** <ul> 640** <li> [SQLITE_LOCK_NONE], 641** <li> [SQLITE_LOCK_SHARED], 642** <li> [SQLITE_LOCK_RESERVED], 643** <li> [SQLITE_LOCK_PENDING], or 644** <li> [SQLITE_LOCK_EXCLUSIVE]. 645** </ul> 646** xLock() increases the lock. xUnlock() decreases the lock. 647** The xCheckReservedLock() method checks whether any database connection, 648** either in this process or in some other process, is holding a RESERVED, 649** PENDING, or EXCLUSIVE lock on the file. It returns true 650** if such a lock exists and false otherwise. 651** 652** The xFileControl() method is a generic interface that allows custom 653** VFS implementations to directly control an open file using the 654** [sqlite3_file_control()] interface. The second "op" argument is an 655** integer opcode. The third argument is a generic pointer intended to 656** point to a structure that may contain arguments or space in which to 657** write return values. Potential uses for xFileControl() might be 658** functions to enable blocking locks with timeouts, to change the 659** locking strategy (for example to use dot-file locks), to inquire 660** about the status of a lock, or to break stale locks. The SQLite 661** core reserves all opcodes less than 100 for its own use. 662** A [SQLITE_FCNTL_LOCKSTATE | list of opcodes] less than 100 is available. 663** Applications that define a custom xFileControl method should use opcodes 664** greater than 100 to avoid conflicts. 665** 666** The xSectorSize() method returns the sector size of the 667** device that underlies the file. The sector size is the 668** minimum write that can be performed without disturbing 669** other bytes in the file. The xDeviceCharacteristics() 670** method returns a bit vector describing behaviors of the 671** underlying device: 672** 673** <ul> 674** <li> [SQLITE_IOCAP_ATOMIC] 675** <li> [SQLITE_IOCAP_ATOMIC512] 676** <li> [SQLITE_IOCAP_ATOMIC1K] 677** <li> [SQLITE_IOCAP_ATOMIC2K] 678** <li> [SQLITE_IOCAP_ATOMIC4K] 679** <li> [SQLITE_IOCAP_ATOMIC8K] 680** <li> [SQLITE_IOCAP_ATOMIC16K] 681** <li> [SQLITE_IOCAP_ATOMIC32K] 682** <li> [SQLITE_IOCAP_ATOMIC64K] 683** <li> [SQLITE_IOCAP_SAFE_APPEND] 684** <li> [SQLITE_IOCAP_SEQUENTIAL] 685** </ul> 686** 687** The SQLITE_IOCAP_ATOMIC property means that all writes of 688** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 689** mean that writes of blocks that are nnn bytes in size and 690** are aligned to an address which is an integer multiple of 691** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 692** that when data is appended to a file, the data is appended 693** first then the size of the file is extended, never the other 694** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 695** information is written to disk in the same order as calls 696** to xWrite(). 697*/ 698typedef struct sqlite3_io_methods sqlite3_io_methods; 699struct sqlite3_io_methods { 700 int iVersion; 701 int (*xClose)(sqlite3_file*); 702 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); 703 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); 704 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); 705 int (*xSync)(sqlite3_file*, int flags); 706 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); 707 int (*xLock)(sqlite3_file*, int); 708 int (*xUnlock)(sqlite3_file*, int); 709 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); 710 int (*xFileControl)(sqlite3_file*, int op, void *pArg); 711 int (*xSectorSize)(sqlite3_file*); 712 int (*xDeviceCharacteristics)(sqlite3_file*); 713 /* Additional methods may be added in future releases */ 714}; 715 716/* 717** CAPI3REF: Standard File Control Opcodes {H11310} <S30800> 718** 719** These integer constants are opcodes for the xFileControl method 720** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] 721** interface. 722** 723** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This 724** opcode causes the xFileControl method to write the current state of 725** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], 726** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) 727** into an integer that the pArg argument points to. This capability 728** is used during testing and only needs to be supported when SQLITE_TEST 729** is defined. 730*/ 731#define SQLITE_FCNTL_LOCKSTATE 1 732 733/* 734** CAPI3REF: Mutex Handle {H17110} <S20130> 735** 736** The mutex module within SQLite defines [sqlite3_mutex] to be an 737** abstract type for a mutex object. The SQLite core never looks 738** at the internal representation of an [sqlite3_mutex]. It only 739** deals with pointers to the [sqlite3_mutex] object. 740** 741** Mutexes are created using [sqlite3_mutex_alloc()]. 742*/ 743typedef struct sqlite3_mutex sqlite3_mutex; 744 745/* 746** CAPI3REF: OS Interface Object {H11140} <S20100> 747** 748** An instance of the sqlite3_vfs object defines the interface between 749** the SQLite core and the underlying operating system. The "vfs" 750** in the name of the object stands for "virtual file system". 751** 752** The value of the iVersion field is initially 1 but may be larger in 753** future versions of SQLite. Additional fields may be appended to this 754** object when the iVersion value is increased. Note that the structure 755** of the sqlite3_vfs object changes in the transaction between 756** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not 757** modified. 758** 759** The szOsFile field is the size of the subclassed [sqlite3_file] 760** structure used by this VFS. mxPathname is the maximum length of 761** a pathname in this VFS. 762** 763** Registered sqlite3_vfs objects are kept on a linked list formed by 764** the pNext pointer. The [sqlite3_vfs_register()] 765** and [sqlite3_vfs_unregister()] interfaces manage this list 766** in a thread-safe way. The [sqlite3_vfs_find()] interface 767** searches the list. Neither the application code nor the VFS 768** implementation should use the pNext pointer. 769** 770** The pNext field is the only field in the sqlite3_vfs 771** structure that SQLite will ever modify. SQLite will only access 772** or modify this field while holding a particular static mutex. 773** The application should never modify anything within the sqlite3_vfs 774** object once the object has been registered. 775** 776** The zName field holds the name of the VFS module. The name must 777** be unique across all VFS modules. 778** 779** {H11141} SQLite will guarantee that the zFilename parameter to xOpen 780** is either a NULL pointer or string obtained 781** from xFullPathname(). SQLite further guarantees that 782** the string will be valid and unchanged until xClose() is 783** called. {END} Because of the previous sentense, 784** the [sqlite3_file] can safely store a pointer to the 785** filename if it needs to remember the filename for some reason. 786** If the zFilename parameter is xOpen is a NULL pointer then xOpen 787** must invite its own temporary name for the file. Whenever the 788** xFilename parameter is NULL it will also be the case that the 789** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. 790** 791** {H11142} The flags argument to xOpen() includes all bits set in 792** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] 793** or [sqlite3_open16()] is used, then flags includes at least 794** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. {END} 795** If xOpen() opens a file read-only then it sets *pOutFlags to 796** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. 797** 798** {H11143} SQLite will also add one of the following flags to the xOpen() 799** call, depending on the object being opened: 800** 801** <ul> 802** <li> [SQLITE_OPEN_MAIN_DB] 803** <li> [SQLITE_OPEN_MAIN_JOURNAL] 804** <li> [SQLITE_OPEN_TEMP_DB] 805** <li> [SQLITE_OPEN_TEMP_JOURNAL] 806** <li> [SQLITE_OPEN_TRANSIENT_DB] 807** <li> [SQLITE_OPEN_SUBJOURNAL] 808** <li> [SQLITE_OPEN_MASTER_JOURNAL] 809** </ul> {END} 810** 811** The file I/O implementation can use the object type flags to 812** change the way it deals with files. For example, an application 813** that does not care about crash recovery or rollback might make 814** the open of a journal file a no-op. Writes to this journal would 815** also be no-ops, and any attempt to read the journal would return 816** SQLITE_IOERR. Or the implementation might recognize that a database 817** file will be doing page-aligned sector reads and writes in a random 818** order and set up its I/O subsystem accordingly. 819** 820** SQLite might also add one of the following flags to the xOpen method: 821** 822** <ul> 823** <li> [SQLITE_OPEN_DELETEONCLOSE] 824** <li> [SQLITE_OPEN_EXCLUSIVE] 825** </ul> 826** 827** {H11145} The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be 828** deleted when it is closed. {H11146} The [SQLITE_OPEN_DELETEONCLOSE] 829** will be set for TEMP databases, journals and for subjournals. 830** 831** {H11147} The [SQLITE_OPEN_EXCLUSIVE] flag means the file should be opened 832** for exclusive access. This flag is set for all files except 833** for the main database file. 834** 835** {H11148} At least szOsFile bytes of memory are allocated by SQLite 836** to hold the [sqlite3_file] structure passed as the third 837** argument to xOpen. {END} The xOpen method does not have to 838** allocate the structure; it should just fill it in. 839** 840** {H11149} The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 841** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to 842** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] 843** to test whether a file is at least readable. {END} The file can be a 844** directory. 845** 846** {H11150} SQLite will always allocate at least mxPathname+1 bytes for the 847** output buffer xFullPathname. {H11151} The exact size of the output buffer 848** is also passed as a parameter to both methods. {END} If the output buffer 849** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is 850** handled as a fatal error by SQLite, vfs implementations should endeavor 851** to prevent this by setting mxPathname to a sufficiently large value. 852** 853** The xRandomness(), xSleep(), and xCurrentTime() interfaces 854** are not strictly a part of the filesystem, but they are 855** included in the VFS structure for completeness. 856** The xRandomness() function attempts to return nBytes bytes 857** of good-quality randomness into zOut. The return value is 858** the actual number of bytes of randomness obtained. 859** The xSleep() method causes the calling thread to sleep for at 860** least the number of microseconds given. The xCurrentTime() 861** method returns a Julian Day Number for the current date and time. 862*/ 863typedef struct sqlite3_vfs sqlite3_vfs; 864struct sqlite3_vfs { 865 int iVersion; /* Structure version number */ 866 int szOsFile; /* Size of subclassed sqlite3_file */ 867 int mxPathname; /* Maximum file pathname length */ 868 sqlite3_vfs *pNext; /* Next registered VFS */ 869 const char *zName; /* Name of this virtual file system */ 870 void *pAppData; /* Pointer to application-specific data */ 871 int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, 872 int flags, int *pOutFlags); 873 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); 874 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); 875 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); 876 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); 877 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); 878 void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol); 879 void (*xDlClose)(sqlite3_vfs*, void*); 880 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); 881 int (*xSleep)(sqlite3_vfs*, int microseconds); 882 int (*xCurrentTime)(sqlite3_vfs*, double*); 883 int (*xGetLastError)(sqlite3_vfs*, int, char *); 884 /* New fields may be appended in figure versions. The iVersion 885 ** value will increment whenever this happens. */ 886}; 887 888/* 889** CAPI3REF: Flags for the xAccess VFS method {H11190} <H11140> 890** 891** {H11191} These integer constants can be used as the third parameter to 892** the xAccess method of an [sqlite3_vfs] object. {END} They determine 893** what kind of permissions the xAccess method is looking for. 894** {H11192} With SQLITE_ACCESS_EXISTS, the xAccess method 895** simply checks whether the file exists. 896** {H11193} With SQLITE_ACCESS_READWRITE, the xAccess method 897** checks whether the file is both readable and writable. 898** {H11194} With SQLITE_ACCESS_READ, the xAccess method 899** checks whether the file is readable. 900*/ 901#define SQLITE_ACCESS_EXISTS 0 902#define SQLITE_ACCESS_READWRITE 1 903#define SQLITE_ACCESS_READ 2 904 905/* 906** CAPI3REF: Initialize The SQLite Library {H10130} <S20000><S30100> 907** 908** The sqlite3_initialize() routine initializes the 909** SQLite library. The sqlite3_shutdown() routine 910** deallocates any resources that were allocated by sqlite3_initialize(). 911** 912** A call to sqlite3_initialize() is an "effective" call if it is 913** the first time sqlite3_initialize() is invoked during the lifetime of 914** the process, or if it is the first time sqlite3_initialize() is invoked 915** following a call to sqlite3_shutdown(). Only an effective call 916** of sqlite3_initialize() does any initialization. All other calls 917** are harmless no-ops. 918** 919** Among other things, sqlite3_initialize() shall invoke 920** sqlite3_os_init(). Similarly, sqlite3_shutdown() 921** shall invoke sqlite3_os_end(). 922** 923** The sqlite3_initialize() routine returns SQLITE_OK on success. 924** If for some reason, sqlite3_initialize() is unable to initialize 925** the library (perhaps it is unable to allocate a needed resource such 926** as a mutex) it returns an [error code] other than SQLITE_OK. 927** 928** The sqlite3_initialize() routine is called internally by many other 929** SQLite interfaces so that an application usually does not need to 930** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] 931** calls sqlite3_initialize() so the SQLite library will be automatically 932** initialized when [sqlite3_open()] is called if it has not be initialized 933** already. However, if SQLite is compiled with the SQLITE_OMIT_AUTOINIT 934** compile-time option, then the automatic calls to sqlite3_initialize() 935** are omitted and the application must call sqlite3_initialize() directly 936** prior to using any other SQLite interface. For maximum portability, 937** it is recommended that applications always invoke sqlite3_initialize() 938** directly prior to using any other SQLite interface. Future releases 939** of SQLite may require this. In other words, the behavior exhibited 940** when SQLite is compiled with SQLITE_OMIT_AUTOINIT might become the 941** default behavior in some future release of SQLite. 942** 943** The sqlite3_os_init() routine does operating-system specific 944** initialization of the SQLite library. The sqlite3_os_end() 945** routine undoes the effect of sqlite3_os_init(). Typical tasks 946** performed by these routines include allocation or deallocation 947** of static resources, initialization of global variables, 948** setting up a default [sqlite3_vfs] module, or setting up 949** a default configuration using [sqlite3_config()]. 950** 951** The application should never invoke either sqlite3_os_init() 952** or sqlite3_os_end() directly. The application should only invoke 953** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() 954** interface is called automatically by sqlite3_initialize() and 955** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate 956** implementations for sqlite3_os_init() and sqlite3_os_end() 957** are built into SQLite when it is compiled for unix, windows, or os/2. 958** When built for other platforms (using the SQLITE_OS_OTHER=1 compile-time 959** option) the application must supply a suitable implementation for 960** sqlite3_os_init() and sqlite3_os_end(). An application-supplied 961** implementation of sqlite3_os_init() or sqlite3_os_end() 962** must return SQLITE_OK on success and some other [error code] upon 963** failure. 964*/ 965int sqlite3_initialize(void); 966int sqlite3_shutdown(void); 967int sqlite3_os_init(void); 968int sqlite3_os_end(void); 969 970/* 971** CAPI3REF: Configuring The SQLite Library {H10145} <S20000><S30200> 972** EXPERIMENTAL 973** 974** The sqlite3_config() interface is used to make global configuration 975** changes to SQLite in order to tune SQLite to the specific needs of 976** the application. The default configuration is recommended for most 977** applications and so this routine is usually not necessary. It is 978** provided to support rare applications with unusual needs. 979** 980** The sqlite3_config() interface is not threadsafe. The application 981** must insure that no other SQLite interfaces are invoked by other 982** threads while sqlite3_config() is running. Furthermore, sqlite3_config() 983** may only be invoked prior to library initialization using 984** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. 985** Note, however, that sqlite3_config() can be called as part of the 986** implementation of an application-defined [sqlite3_os_init()]. 987** 988** The first argument to sqlite3_config() is an integer 989** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines 990** what property of SQLite is to be configured. Subsequent arguments 991** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option] 992** in the first argument. 993** 994** When a configuration option is set, sqlite3_config() returns SQLITE_OK. 995** If the option is unknown or SQLite is unable to set the option 996** then this routine returns a non-zero [error code]. 997*/ 998SQLITE_EXPERIMENTAL int sqlite3_config(int, ...); 999 1000/* 1001** CAPI3REF: Configure database connections {H10180} <S20000> 1002** EXPERIMENTAL 1003** 1004** The sqlite3_db_config() interface is used to make configuration 1005** changes to a [database connection]. The interface is similar to 1006** [sqlite3_config()] except that the changes apply to a single 1007** [database connection] (specified in the first argument). The 1008** sqlite3_db_config() interface can only be used immediately after 1009** the database connection is created using [sqlite3_open()], 1010** [sqlite3_open16()], or [sqlite3_open_v2()]. 1011** 1012** The second argument to sqlite3_db_config(D,V,...) is the 1013** configuration verb - an integer code that indicates what 1014** aspect of the [database connection] is being configured. 1015** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE]. 1016** New verbs are likely to be added in future releases of SQLite. 1017** Additional arguments depend on the verb. 1018*/ 1019SQLITE_EXPERIMENTAL int sqlite3_db_config(sqlite3*, int op, ...); 1020 1021/* 1022** CAPI3REF: Memory Allocation Routines {H10155} <S20120> 1023** EXPERIMENTAL 1024** 1025** An instance of this object defines the interface between SQLite 1026** and low-level memory allocation routines. 1027** 1028** This object is used in only one place in the SQLite interface. 1029** A pointer to an instance of this object is the argument to 1030** [sqlite3_config()] when the configuration option is 1031** [SQLITE_CONFIG_MALLOC]. By creating an instance of this object 1032** and passing it to [sqlite3_config()] during configuration, an 1033** application can specify an alternative memory allocation subsystem 1034** for SQLite to use for all of its dynamic memory needs. 1035** 1036** Note that SQLite comes with a built-in memory allocator that is 1037** perfectly adequate for the overwhelming majority of applications 1038** and that this object is only useful to a tiny minority of applications 1039** with specialized memory allocation requirements. This object is 1040** also used during testing of SQLite in order to specify an alternative 1041** memory allocator that simulates memory out-of-memory conditions in 1042** order to verify that SQLite recovers gracefully from such 1043** conditions. 1044** 1045** The xMalloc, xFree, and xRealloc methods must work like the 1046** malloc(), free(), and realloc() functions from the standard library. 1047** 1048** xSize should return the allocated size of a memory allocation 1049** previously obtained from xMalloc or xRealloc. The allocated size 1050** is always at least as big as the requested size but may be larger. 1051** 1052** The xRoundup method returns what would be the allocated size of 1053** a memory allocation given a particular requested size. Most memory 1054** allocators round up memory allocations at least to the next multiple 1055** of 8. Some allocators round up to a larger multiple or to a power of 2. 1056** 1057** The xInit method initializes the memory allocator. (For example, 1058** it might allocate any require mutexes or initialize internal data 1059** structures. The xShutdown method is invoked (indirectly) by 1060** [sqlite3_shutdown()] and should deallocate any resources acquired 1061** by xInit. The pAppData pointer is used as the only parameter to 1062** xInit and xShutdown. 1063*/ 1064typedef struct sqlite3_mem_methods sqlite3_mem_methods; 1065struct sqlite3_mem_methods { 1066 void *(*xMalloc)(int); /* Memory allocation function */ 1067 void (*xFree)(void*); /* Free a prior allocation */ 1068 void *(*xRealloc)(void*,int); /* Resize an allocation */ 1069 int (*xSize)(void*); /* Return the size of an allocation */ 1070 int (*xRoundup)(int); /* Round up request size to allocation size */ 1071 int (*xInit)(void*); /* Initialize the memory allocator */ 1072 void (*xShutdown)(void*); /* Deinitialize the memory allocator */ 1073 void *pAppData; /* Argument to xInit() and xShutdown() */ 1074}; 1075 1076/* 1077** CAPI3REF: Configuration Options {H10160} <S20000> 1078** EXPERIMENTAL 1079** 1080** These constants are the available integer configuration options that 1081** can be passed as the first argument to the [sqlite3_config()] interface. 1082** 1083** New configuration options may be added in future releases of SQLite. 1084** Existing configuration options might be discontinued. Applications 1085** should check the return code from [sqlite3_config()] to make sure that 1086** the call worked. The [sqlite3_config()] interface will return a 1087** non-zero [error code] if a discontinued or unsupported configuration option 1088** is invoked. 1089** 1090** <dl> 1091** <dt>SQLITE_CONFIG_SINGLETHREAD</dt> 1092** <dd>There are no arguments to this option. This option disables 1093** all mutexing and puts SQLite into a mode where it can only be used 1094** by a single thread.</dd> 1095** 1096** <dt>SQLITE_CONFIG_MULTITHREAD</dt> 1097** <dd>There are no arguments to this option. This option disables 1098** mutexing on [database connection] and [prepared statement] objects. 1099** The application is responsible for serializing access to 1100** [database connections] and [prepared statements]. But other mutexes 1101** are enabled so that SQLite will be safe to use in a multi-threaded 1102** environment as long as no two threads attempt to use the same 1103** [database connection] at the same time. See the [threading mode] 1104** documentation for additional information.</dd> 1105** 1106** <dt>SQLITE_CONFIG_SERIALIZED</dt> 1107** <dd>There are no arguments to this option. This option enables 1108** all mutexes including the recursive 1109** mutexes on [database connection] and [prepared statement] objects. 1110** In this mode (which is the default when SQLite is compiled with 1111** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access 1112** to [database connections] and [prepared statements] so that the 1113** application is free to use the same [database connection] or the 1114** same [prepared statement] in different threads at the same time. 1115** See the [threading mode] documentation for additional information.</dd> 1116** 1117** <dt>SQLITE_CONFIG_MALLOC</dt> 1118** <dd>This option takes a single argument which is a pointer to an 1119** instance of the [sqlite3_mem_methods] structure. The argument specifies 1120** alternative low-level memory allocation routines to be used in place of 1121** the memory allocation routines built into SQLite.</dd> 1122** 1123** <dt>SQLITE_CONFIG_GETMALLOC</dt> 1124** <dd>This option takes a single argument which is a pointer to an 1125** instance of the [sqlite3_mem_methods] structure. The [sqlite3_mem_methods] 1126** structure is filled with the currently defined memory allocation routines. 1127** This option can be used to overload the default memory allocation 1128** routines with a wrapper that simulations memory allocation failure or 1129** tracks memory usage, for example.</dd> 1130** 1131** <dt>SQLITE_CONFIG_MEMSTATUS</dt> 1132** <dd>This option takes single argument of type int, interpreted as a 1133** boolean, which enables or disables the collection of memory allocation 1134** statistics. When disabled, the following SQLite interfaces become 1135** non-operational: 1136** <ul> 1137** <li> [sqlite3_memory_used()] 1138** <li> [sqlite3_memory_highwater()] 1139** <li> [sqlite3_soft_heap_limit()] 1140** <li> [sqlite3_status()] 1141** </ul> 1142** </dd> 1143** 1144** <dt>SQLITE_CONFIG_SCRATCH</dt> 1145** <dd>This option specifies a static memory buffer that SQLite can use for 1146** scratch memory. There are three arguments: A pointer to the memory, the 1147** size of each scratch buffer (sz), and the number of buffers (N). The sz 1148** argument must be a multiple of 16. The sz parameter should be a few bytes 1149** larger than the actual scratch space required due internal overhead. 1150** The first 1151** argument should point to an allocation of at least sz*N bytes of memory. 1152** SQLite will use no more than one scratch buffer at once per thread, so 1153** N should be set to the expected maximum number of threads. The sz 1154** parameter should be 6 times the size of the largest database page size. 1155** Scratch buffers are used as part of the btree balance operation. If 1156** The btree balancer needs additional memory beyond what is provided by 1157** scratch buffers or if no scratch buffer space is specified, then SQLite 1158** goes to [sqlite3_malloc()] to obtain the memory it needs.</dd> 1159** 1160** <dt>SQLITE_CONFIG_PAGECACHE</dt> 1161** <dd>This option specifies a static memory buffer that SQLite can use for 1162** the database page cache. There are three arguments: A pointer to the 1163** memory, the size of each page buffer (sz), and the number of pages (N). 1164** The sz argument must be a power of two between 512 and 32768. The first 1165** argument should point to an allocation of at least sz*N bytes of memory. 1166** SQLite will use the memory provided by the first argument to satisfy its 1167** memory needs for the first N pages that it adds to cache. If additional 1168** page cache memory is needed beyond what is provided by this option, then 1169** SQLite goes to [sqlite3_malloc()] for the additional storage space. 1170** The implementation might use one or more of the N buffers to hold 1171** memory accounting information. </dd> 1172** 1173** <dt>SQLITE_CONFIG_HEAP</dt> 1174** <dd>This option specifies a static memory buffer that SQLite will use 1175** for all of its dynamic memory allocation needs beyond those provided 1176** for by [SQLITE_CONFIG_SCRATCH] and [SQLITE_CONFIG_PAGECACHE]. 1177** There are three arguments: A pointer to the memory, the number of 1178** bytes in the memory buffer, and the minimum allocation size. If 1179** the first pointer (the memory pointer) is NULL, then SQLite reverts 1180** to using its default memory allocator (the system malloc() implementation), 1181** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. If the 1182** memory pointer is not NULL and either [SQLITE_ENABLE_MEMSYS3] or 1183** [SQLITE_ENABLE_MEMSYS5] are defined, then the alternative memory 1184** allocator is engaged to handle all of SQLites memory allocation needs.</dd> 1185** 1186** <dt>SQLITE_CONFIG_MUTEX</dt> 1187** <dd>This option takes a single argument which is a pointer to an 1188** instance of the [sqlite3_mutex_methods] structure. The argument specifies 1189** alternative low-level mutex routines to be used in place 1190** the mutex routines built into SQLite.</dd> 1191** 1192** <dt>SQLITE_CONFIG_GETMUTEX</dt> 1193** <dd>This option takes a single argument which is a pointer to an 1194** instance of the [sqlite3_mutex_methods] structure. The 1195** [sqlite3_mutex_methods] 1196** structure is filled with the currently defined mutex routines. 1197** This option can be used to overload the default mutex allocation 1198** routines with a wrapper used to track mutex usage for performance 1199** profiling or testing, for example.</dd> 1200** 1201** <dt>SQLITE_CONFIG_LOOKASIDE</dt> 1202** <dd>This option takes two arguments that determine the default 1203** memory allcation lookaside optimization. The first argument is the 1204** size of each lookaside buffer slot and the second is the number of 1205** slots allocated to each database connection.</dd> 1206** 1207** </dl> 1208*/ 1209#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ 1210#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ 1211#define SQLITE_CONFIG_SERIALIZED 3 /* nil */ 1212#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ 1213#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ 1214#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */ 1215#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ 1216#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ 1217#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ 1218#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ 1219#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ 1220#define SQLITE_CONFIG_CHUNKALLOC 12 /* int threshold */ 1221#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ 1222 1223/* 1224** CAPI3REF: Configuration Options {H10170} <S20000> 1225** EXPERIMENTAL 1226** 1227** These constants are the available integer configuration options that 1228** can be passed as the second argument to the [sqlite3_db_config()] interface. 1229** 1230** New configuration options may be added in future releases of SQLite. 1231** Existing configuration options might be discontinued. Applications 1232** should check the return code from [sqlite3_db_config()] to make sure that 1233** the call worked. The [sqlite3_db_config()] interface will return a 1234** non-zero [error code] if a discontinued or unsupported configuration option 1235** is invoked. 1236** 1237** <dl> 1238** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> 1239** <dd>This option takes three additional arguments that determine the 1240** [lookaside memory allocator] configuration for the [database connection]. 1241** The first argument (the third parameter to [sqlite3_db_config()] is a 1242** pointer to a memory buffer to use for lookaside memory. The first 1243** argument may be NULL in which case SQLite will allocate the lookaside 1244** buffer itself using [sqlite3_malloc()]. The second argument is the 1245** size of each lookaside buffer slot and the third argument is the number of 1246** slots. The size of the buffer in the first argument must be greater than 1247** or equal to the product of the second and third arguments.</dd> 1248** 1249** </dl> 1250*/ 1251#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ 1252 1253 1254/* 1255** CAPI3REF: Enable Or Disable Extended Result Codes {H12200} <S10700> 1256** 1257** The sqlite3_extended_result_codes() routine enables or disables the 1258** [extended result codes] feature of SQLite. The extended result 1259** codes are disabled by default for historical compatibility considerations. 1260** 1261** INVARIANTS: 1262** 1263** {H12201} Each new [database connection] shall have the 1264** [extended result codes] feature disabled by default. 1265** 1266** {H12202} The [sqlite3_extended_result_codes(D,F)] interface shall enable 1267** [extended result codes] for the [database connection] D 1268** if the F parameter is true, or disable them if F is false. 1269*/ 1270int sqlite3_extended_result_codes(sqlite3*, int onoff); 1271 1272/* 1273** CAPI3REF: Last Insert Rowid {H12220} <S10700> 1274** 1275** Each entry in an SQLite table has a unique 64-bit signed 1276** integer key called the "rowid". The rowid is always available 1277** as an undeclared column named ROWID, OID, or _ROWID_ as long as those 1278** names are not also used by explicitly declared columns. If 1279** the table has a column of type INTEGER PRIMARY KEY then that column 1280** is another alias for the rowid. 1281** 1282** This routine returns the rowid of the most recent 1283** successful INSERT into the database from the [database connection] 1284** in the first argument. If no successful INSERTs 1285** have ever occurred on that database connection, zero is returned. 1286** 1287** If an INSERT occurs within a trigger, then the rowid of the inserted 1288** row is returned by this routine as long as the trigger is running. 1289** But once the trigger terminates, the value returned by this routine 1290** reverts to the last value inserted before the trigger fired. 1291** 1292** An INSERT that fails due to a constraint violation is not a 1293** successful INSERT and does not change the value returned by this 1294** routine. Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, 1295** and INSERT OR ABORT make no changes to the return value of this 1296** routine when their insertion fails. When INSERT OR REPLACE 1297** encounters a constraint violation, it does not fail. The 1298** INSERT continues to completion after deleting rows that caused 1299** the constraint problem so INSERT OR REPLACE will always change 1300** the return value of this interface. 1301** 1302** For the purposes of this routine, an INSERT is considered to 1303** be successful even if it is subsequently rolled back. 1304** 1305** INVARIANTS: 1306** 1307** {H12221} The [sqlite3_last_insert_rowid()] function returns the rowid 1308** of the most recent successful INSERT performed on the same 1309** [database connection] and within the same or higher level 1310** trigger context, or zero if there have been no qualifying inserts. 1311** 1312** {H12223} The [sqlite3_last_insert_rowid()] function returns the 1313** same value when called from the same trigger context 1314** immediately before and after a ROLLBACK. 1315** 1316** ASSUMPTIONS: 1317** 1318** {A12232} If a separate thread performs a new INSERT on the same 1319** database connection while the [sqlite3_last_insert_rowid()] 1320** function is running and thus changes the last insert rowid, 1321** then the value returned by [sqlite3_last_insert_rowid()] is 1322** unpredictable and might not equal either the old or the new 1323** last insert rowid. 1324*/ 1325sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); 1326 1327/* 1328** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600> 1329** 1330** This function returns the number of database rows that were changed 1331** or inserted or deleted by the most recently completed SQL statement 1332** on the [database connection] specified by the first parameter. 1333** Only changes that are directly specified by the INSERT, UPDATE, 1334** or DELETE statement are counted. Auxiliary changes caused by 1335** triggers are not counted. Use the [sqlite3_total_changes()] function 1336** to find the total number of changes including changes caused by triggers. 1337** 1338** A "row change" is a change to a single row of a single table 1339** caused by an INSERT, DELETE, or UPDATE statement. Rows that 1340** are changed as side effects of REPLACE constraint resolution, 1341** rollback, ABORT processing, DROP TABLE, or by any other 1342** mechanisms do not count as direct row changes. 1343** 1344** A "trigger context" is a scope of execution that begins and 1345** ends with the script of a trigger. Most SQL statements are 1346** evaluated outside of any trigger. This is the "top level" 1347** trigger context. If a trigger fires from the top level, a 1348** new trigger context is entered for the duration of that one 1349** trigger. Subtriggers create subcontexts for their duration. 1350** 1351** Calling [sqlite3_exec()] or [sqlite3_step()] recursively does 1352** not create a new trigger context. 1353** 1354** This function returns the number of direct row changes in the 1355** most recent INSERT, UPDATE, or DELETE statement within the same 1356** trigger context. 1357** 1358** Thus, when called from the top level, this function returns the 1359** number of changes in the most recent INSERT, UPDATE, or DELETE 1360** that also occurred at the top level. Within the body of a trigger, 1361** the sqlite3_changes() interface can be called to find the number of 1362** changes in the most recently completed INSERT, UPDATE, or DELETE 1363** statement within the body of the same trigger. 1364** However, the number returned does not include changes 1365** caused by subtriggers since those have their own context. 1366** 1367** SQLite implements the command "DELETE FROM table" without a WHERE clause 1368** by dropping and recreating the table. (This is much faster than going 1369** through and deleting individual elements from the table.) Because of this 1370** optimization, the deletions in "DELETE FROM table" are not row changes and 1371** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()] 1372** functions, regardless of the number of elements that were originally 1373** in the table. To get an accurate count of the number of rows deleted, use 1374** "DELETE FROM table WHERE 1" instead. 1375** 1376** INVARIANTS: 1377** 1378** {H12241} The [sqlite3_changes()] function shall return the number of 1379** row changes caused by the most recent INSERT, UPDATE, 1380** or DELETE statement on the same database connection and 1381** within the same or higher trigger context, or zero if there have 1382** not been any qualifying row changes. 1383** 1384** {H12243} Statements of the form "DELETE FROM tablename" with no 1385** WHERE clause shall cause subsequent calls to 1386** [sqlite3_changes()] to return zero, regardless of the 1387** number of rows originally in the table. 1388** 1389** ASSUMPTIONS: 1390** 1391** {A12252} If a separate thread makes changes on the same database connection 1392** while [sqlite3_changes()] is running then the value returned 1393** is unpredictable and not meaningful. 1394*/ 1395int sqlite3_changes(sqlite3*); 1396 1397/* 1398** CAPI3REF: Total Number Of Rows Modified {H12260} <S10600> 1399** 1400** This function returns the number of row changes caused by INSERT, 1401** UPDATE or DELETE statements since the [database connection] was opened. 1402** The count includes all changes from all trigger contexts. However, 1403** the count does not include changes used to implement REPLACE constraints, 1404** do rollbacks or ABORT processing, or DROP table processing. 1405** The changes are counted as soon as the statement that makes them is 1406** completed (when the statement handle is passed to [sqlite3_reset()] or 1407** [sqlite3_finalize()]). 1408** 1409** SQLite implements the command "DELETE FROM table" without a WHERE clause 1410** by dropping and recreating the table. (This is much faster than going 1411** through and deleting individual elements from the table.) Because of this 1412** optimization, the deletions in "DELETE FROM table" are not row changes and 1413** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()] 1414** functions, regardless of the number of elements that were originally 1415** in the table. To get an accurate count of the number of rows deleted, use 1416** "DELETE FROM table WHERE 1" instead. 1417** 1418** See also the [sqlite3_changes()] interface. 1419** 1420** INVARIANTS: 1421** 1422** {H12261} The [sqlite3_total_changes()] returns the total number 1423** of row changes caused by INSERT, UPDATE, and/or DELETE 1424** statements on the same [database connection], in any 1425** trigger context, since the database connection was created. 1426** 1427** {H12263} Statements of the form "DELETE FROM tablename" with no 1428** WHERE clause shall not change the value returned 1429** by [sqlite3_total_changes()]. 1430** 1431** ASSUMPTIONS: 1432** 1433** {A12264} If a separate thread makes changes on the same database connection 1434** while [sqlite3_total_changes()] is running then the value 1435** returned is unpredictable and not meaningful. 1436*/ 1437int sqlite3_total_changes(sqlite3*); 1438 1439/* 1440** CAPI3REF: Interrupt A Long-Running Query {H12270} <S30500> 1441** 1442** This function causes any pending database operation to abort and 1443** return at its earliest opportunity. This routine is typically 1444** called in response to a user action such as pressing "Cancel" 1445** or Ctrl-C where the user wants a long query operation to halt 1446** immediately. 1447** 1448** It is safe to call this routine from a thread different from the 1449** thread that is currently running the database operation. But it 1450** is not safe to call this routine with a [database connection] that 1451** is closed or might close before sqlite3_interrupt() returns. 1452** 1453** If an SQL operation is very nearly finished at the time when 1454** sqlite3_interrupt() is called, then it might not have an opportunity 1455** to be interrupted and might continue to completion. 1456** 1457** An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. 1458** If the interrupted SQL operation is an INSERT, UPDATE, or DELETE 1459** that is inside an explicit transaction, then the entire transaction 1460** will be rolled back automatically. 1461** 1462** A call to sqlite3_interrupt() has no effect on SQL statements 1463** that are started after sqlite3_interrupt() returns. 1464** 1465** INVARIANTS: 1466** 1467** {H12271} The [sqlite3_interrupt()] interface will force all running 1468** SQL statements associated with the same database connection 1469** to halt after processing at most one additional row of data. 1470** 1471** {H12272} Any SQL statement that is interrupted by [sqlite3_interrupt()] 1472** will return [SQLITE_INTERRUPT]. 1473** 1474** ASSUMPTIONS: 1475** 1476** {A12279} If the database connection closes while [sqlite3_interrupt()] 1477** is running then bad things will likely happen. 1478*/ 1479void sqlite3_interrupt(sqlite3*); 1480 1481/* 1482** CAPI3REF: Determine If An SQL Statement Is Complete {H10510} <S70200> 1483** 1484** These routines are useful for command-line input to determine if the 1485** currently entered text seems to form complete a SQL statement or 1486** if additional input is needed before sending the text into 1487** SQLite for parsing. These routines return true if the input string 1488** appears to be a complete SQL statement. A statement is judged to be 1489** complete if it ends with a semicolon token and is not a fragment of a 1490** CREATE TRIGGER statement. Semicolons that are embedded within 1491** string literals or quoted identifier names or comments are not 1492** independent tokens (they are part of the token in which they are 1493** embedded) and thus do not count as a statement terminator. 1494** 1495** These routines do not parse the SQL statements thus 1496** will not detect syntactically incorrect SQL. 1497** 1498** INVARIANTS: 1499** 1500** {H10511} A successful evaluation of [sqlite3_complete()] or 1501** [sqlite3_complete16()] functions shall 1502** return a numeric 1 if and only if the last non-whitespace 1503** token in their input is a semicolon that is not in between 1504** the BEGIN and END of a CREATE TRIGGER statement. 1505** 1506** {H10512} If a memory allocation error occurs during an invocation 1507** of [sqlite3_complete()] or [sqlite3_complete16()] then the 1508** routine shall return [SQLITE_NOMEM]. 1509** 1510** ASSUMPTIONS: 1511** 1512** {A10512} The input to [sqlite3_complete()] must be a zero-terminated 1513** UTF-8 string. 1514** 1515** {A10513} The input to [sqlite3_complete16()] must be a zero-terminated 1516** UTF-16 string in native byte order. 1517*/ 1518int sqlite3_complete(const char *sql); 1519int sqlite3_complete16(const void *sql); 1520 1521/* 1522** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors {H12310} <S40400> 1523** 1524** This routine sets a callback function that might be invoked whenever 1525** an attempt is made to open a database table that another thread 1526** or process has locked. 1527** 1528** If the busy callback is NULL, then [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] 1529** is returned immediately upon encountering the lock. If the busy callback 1530** is not NULL, then the callback will be invoked with two arguments. 1531** 1532** The first argument to the handler is a copy of the void* pointer which 1533** is the third argument to sqlite3_busy_handler(). The second argument to 1534** the handler callback is the number of times that the busy handler has 1535** been invoked for this locking event. If the 1536** busy callback returns 0, then no additional attempts are made to 1537** access the database and [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED] is returned. 1538** If the callback returns non-zero, then another attempt 1539** is made to open the database for reading and the cycle repeats. 1540** 1541** The presence of a busy handler does not guarantee that it will be invoked 1542** when there is lock contention. If SQLite determines that invoking the busy 1543** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] 1544** or [SQLITE_IOERR_BLOCKED] instead of invoking the busy handler. 1545** Consider a scenario where one process is holding a read lock that 1546** it is trying to promote to a reserved lock and 1547** a second process is holding a reserved lock that it is trying 1548** to promote to an exclusive lock. The first process cannot proceed 1549** because it is blocked by the second and the second process cannot 1550** proceed because it is blocked by the first. If both processes 1551** invoke the busy handlers, neither will make any progress. Therefore, 1552** SQLite returns [SQLITE_BUSY] for the first process, hoping that this 1553** will induce the first process to release its read lock and allow 1554** the second process to proceed. 1555** 1556** The default busy callback is NULL. 1557** 1558** The [SQLITE_BUSY] error is converted to [SQLITE_IOERR_BLOCKED] 1559** when SQLite is in the middle of a large transaction where all the 1560** changes will not fit into the in-memory cache. SQLite will 1561** already hold a RESERVED lock on the database file, but it needs 1562** to promote this lock to EXCLUSIVE so that it can spill cache 1563** pages into the database file without harm to concurrent 1564** readers. If it is unable to promote the lock, then the in-memory 1565** cache will be left in an inconsistent state and so the error 1566** code is promoted from the relatively benign [SQLITE_BUSY] to 1567** the more severe [SQLITE_IOERR_BLOCKED]. This error code promotion 1568** forces an automatic rollback of the changes. See the 1569** <a href="/cvstrac/wiki?p=CorruptionFollowingBusyError"> 1570** CorruptionFollowingBusyError</a> wiki page for a discussion of why 1571** this is important. 1572** 1573** There can only be a single busy handler defined for each 1574** [database connection]. Setting a new busy handler clears any 1575** previously set handler. Note that calling [sqlite3_busy_timeout()] 1576** will also set or clear the busy handler. 1577** 1578** INVARIANTS: 1579** 1580** {H12311} The [sqlite3_busy_handler(D,C,A)] function shall replace 1581** busy callback in the [database connection] D with a new 1582** a new busy handler C and application data pointer A. 1583** 1584** {H12312} Newly created [database connections] shall have a busy 1585** handler of NULL. 1586** 1587** {H12314} When two or more [database connections] share a 1588** [sqlite3_enable_shared_cache | common cache], 1589** the busy handler for the database connection currently using 1590** the cache shall be invoked when the cache encounters a lock. 1591** 1592** {H12316} If a busy handler callback returns zero, then the SQLite interface 1593** that provoked the locking event shall return [SQLITE_BUSY]. 1594** 1595** {H12318} SQLite shall invokes the busy handler with two arguments which 1596** are a copy of the pointer supplied by the 3rd parameter to 1597** [sqlite3_busy_handler()] and a count of the number of prior 1598** invocations of the busy handler for the same locking event. 1599** 1600** ASSUMPTIONS: 1601** 1602** {A12319} A busy handler must not close the database connection 1603** or [prepared statement] that invoked the busy handler. 1604*/ 1605int sqlite3_busy_handler(sqlite3*, int(*)(void*,int), void*); 1606 1607/* 1608** CAPI3REF: Set A Busy Timeout {H12340} <S40410> 1609** 1610** This routine sets a [sqlite3_busy_handler | busy handler] that sleeps 1611** for a specified amount of time when a table is locked. The handler 1612** will sleep multiple times until at least "ms" milliseconds of sleeping 1613** have accumulated. {H12343} After "ms" milliseconds of sleeping, 1614** the handler returns 0 which causes [sqlite3_step()] to return 1615** [SQLITE_BUSY] or [SQLITE_IOERR_BLOCKED]. 1616** 1617** Calling this routine with an argument less than or equal to zero 1618** turns off all busy handlers. 1619** 1620** There can only be a single busy handler for a particular 1621** [database connection] any any given moment. If another busy handler 1622** was defined (using [sqlite3_busy_handler()]) prior to calling 1623** this routine, that other busy handler is cleared. 1624** 1625** INVARIANTS: 1626** 1627** {H12341} The [sqlite3_busy_timeout()] function shall override any prior 1628** [sqlite3_busy_timeout()] or [sqlite3_busy_handler()] setting 1629** on the same [database connection]. 1630** 1631** {H12343} If the 2nd parameter to [sqlite3_busy_timeout()] is less than 1632** or equal to zero, then the busy handler shall be cleared so that 1633** all subsequent locking events immediately return [SQLITE_BUSY]. 1634** 1635** {H12344} If the 2nd parameter to [sqlite3_busy_timeout()] is a positive 1636** number N, then a busy handler shall be set that repeatedly calls 1637** the xSleep() method in the [sqlite3_vfs | VFS interface] until 1638** either the lock clears or until the cumulative sleep time 1639** reported back by xSleep() exceeds N milliseconds. 1640*/ 1641int sqlite3_busy_timeout(sqlite3*, int ms); 1642 1643/* 1644** CAPI3REF: Convenience Routines For Running Queries {H12370} <S10000> 1645** 1646** Definition: A <b>result table</b> is memory data structure created by the 1647** [sqlite3_get_table()] interface. A result table records the 1648** complete query results from one or more queries. 1649** 1650** The table conceptually has a number of rows and columns. But 1651** these numbers are not part of the result table itself. These 1652** numbers are obtained separately. Let N be the number of rows 1653** and M be the number of columns. 1654** 1655** A result table is an array of pointers to zero-terminated UTF-8 strings. 1656** There are (N+1)*M elements in the array. The first M pointers point 1657** to zero-terminated strings that contain the names of the columns. 1658** The remaining entries all point to query results. NULL values result 1659** in NULL pointers. All other values are in their UTF-8 zero-terminated 1660** string representation as returned by [sqlite3_column_text()]. 1661** 1662** A result table might consist of one or more memory allocations. 1663** It is not safe to pass a result table directly to [sqlite3_free()]. 1664** A result table should be deallocated using [sqlite3_free_table()]. 1665** 1666** As an example of the result table format, suppose a query result 1667** is as follows: 1668** 1669** <blockquote><pre> 1670** Name | Age 1671** ----------------------- 1672** Alice | 43 1673** Bob | 28 1674** Cindy | 21 1675** </pre></blockquote> 1676** 1677** There are two column (M==2) and three rows (N==3). Thus the 1678** result table has 8 entries. Suppose the result table is stored 1679** in an array names azResult. Then azResult holds this content: 1680** 1681** <blockquote><pre> 1682** azResult[0] = "Name"; 1683** azResult[1] = "Age"; 1684** azResult[2] = "Alice"; 1685** azResult[3] = "43"; 1686** azResult[4] = "Bob"; 1687** azResult[5] = "28"; 1688** azResult[6] = "Cindy"; 1689** azResult[7] = "21"; 1690** </pre></blockquote> 1691** 1692** The sqlite3_get_table() function evaluates one or more 1693** semicolon-separated SQL statements in the zero-terminated UTF-8 1694** string of its 2nd parameter. It returns a result table to the 1695** pointer given in its 3rd parameter. 1696** 1697** After the calling function has finished using the result, it should 1698** pass the pointer to the result table to sqlite3_free_table() in order to 1699** release the memory that was malloced. Because of the way the 1700** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling 1701** function must not try to call [sqlite3_free()] directly. Only 1702** [sqlite3_free_table()] is able to release the memory properly and safely. 1703** 1704** The sqlite3_get_table() interface is implemented as a wrapper around 1705** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access 1706** to any internal data structures of SQLite. It uses only the public 1707** interface defined here. As a consequence, errors that occur in the 1708** wrapper layer outside of the internal [sqlite3_exec()] call are not 1709** reflected in subsequent calls to [sqlite3_errcode()] or [sqlite3_errmsg()]. 1710** 1711** INVARIANTS: 1712** 1713** {H12371} If a [sqlite3_get_table()] fails a memory allocation, then 1714** it shall free the result table under construction, abort the 1715** query in process, skip any subsequent queries, set the 1716** *pazResult output pointer to NULL and return [SQLITE_NOMEM]. 1717** 1718** {H12373} If the pnColumn parameter to [sqlite3_get_table()] is not NULL 1719** then a successful invocation of [sqlite3_get_table()] shall 1720** write the number of columns in the 1721** result set of the query into *pnColumn. 1722** 1723** {H12374} If the pnRow parameter to [sqlite3_get_table()] is not NULL 1724** then a successful invocation of [sqlite3_get_table()] shall 1725** writes the number of rows in the 1726** result set of the query into *pnRow. 1727** 1728** {H12376} A successful invocation of [sqlite3_get_table()] that computes 1729** N rows of result with C columns per row shall make *pazResult 1730** point to an array of pointers to (N+1)*C strings where the first 1731** C strings are column names as obtained from 1732** [sqlite3_column_name()] and the rest are column result values 1733** obtained from [sqlite3_column_text()]. 1734** 1735** {H12379} The values in the pazResult array returned by [sqlite3_get_table()] 1736** shall remain valid until cleared by [sqlite3_free_table()]. 1737** 1738** {H12382} When an error occurs during evaluation of [sqlite3_get_table()] 1739** the function shall set *pazResult to NULL, write an error message 1740** into memory obtained from [sqlite3_malloc()], make 1741** **pzErrmsg point to that error message, and return a 1742** appropriate [error code]. 1743*/ 1744int sqlite3_get_table( 1745 sqlite3 *db, /* An open database */ 1746 const char *zSql, /* SQL to be evaluated */ 1747 char ***pazResult, /* Results of the query */ 1748 int *pnRow, /* Number of result rows written here */ 1749 int *pnColumn, /* Number of result columns written here */ 1750 char **pzErrmsg /* Error msg written here */ 1751); 1752void sqlite3_free_table(char **result); 1753 1754/* 1755** CAPI3REF: Formatted String Printing Functions {H17400} <S70000><S20000> 1756** 1757** These routines are workalikes of the "printf()" family of functions 1758** from the standard C library. 1759** 1760** The sqlite3_mprintf() and sqlite3_vmprintf() routines write their 1761** results into memory obtained from [sqlite3_malloc()]. 1762** The strings returned by these two routines should be 1763** released by [sqlite3_free()]. Both routines return a 1764** NULL pointer if [sqlite3_malloc()] is unable to allocate enough 1765** memory to hold the resulting string. 1766** 1767** In sqlite3_snprintf() routine is similar to "snprintf()" from 1768** the standard C library. The result is written into the 1769** buffer supplied as the second parameter whose size is given by 1770** the first parameter. Note that the order of the 1771** first two parameters is reversed from snprintf(). This is an 1772** historical accident that cannot be fixed without breaking 1773** backwards compatibility. Note also that sqlite3_snprintf() 1774** returns a pointer to its buffer instead of the number of 1775** characters actually written into the buffer. We admit that 1776** the number of characters written would be a more useful return 1777** value but we cannot change the implementation of sqlite3_snprintf() 1778** now without breaking compatibility. 1779** 1780** As long as the buffer size is greater than zero, sqlite3_snprintf() 1781** guarantees that the buffer is always zero-terminated. The first 1782** parameter "n" is the total size of the buffer, including space for 1783** the zero terminator. So the longest string that can be completely 1784** written will be n-1 characters. 1785** 1786** These routines all implement some additional formatting 1787** options that are useful for constructing SQL statements. 1788** All of the usual printf() formatting options apply. In addition, there 1789** is are "%q", "%Q", and "%z" options. 1790** 1791** The %q option works like %s in that it substitutes a null-terminated 1792** string from the argument list. But %q also doubles every '\'' character. 1793** %q is designed for use inside a string literal. By doubling each '\'' 1794** character it escapes that character and allows it to be inserted into 1795** the string. 1796** 1797** For example, assume the string variable zText contains text as follows: 1798** 1799** <blockquote><pre> 1800** char *zText = "It's a happy day!"; 1801** </pre></blockquote> 1802** 1803** One can use this text in an SQL statement as follows: 1804** 1805** <blockquote><pre> 1806** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText); 1807** sqlite3_exec(db, zSQL, 0, 0, 0); 1808** sqlite3_free(zSQL); 1809** </pre></blockquote> 1810** 1811** Because the %q format string is used, the '\'' character in zText 1812** is escaped and the SQL generated is as follows: 1813** 1814** <blockquote><pre> 1815** INSERT INTO table1 VALUES('It''s a happy day!') 1816** </pre></blockquote> 1817** 1818** This is correct. Had we used %s instead of %q, the generated SQL 1819** would have looked like this: 1820** 1821** <blockquote><pre> 1822** INSERT INTO table1 VALUES('It's a happy day!'); 1823** </pre></blockquote> 1824** 1825** This second example is an SQL syntax error. As a general rule you should 1826** always use %q instead of %s when inserting text into a string literal. 1827** 1828** The %Q option works like %q except it also adds single quotes around 1829** the outside of the total string. Additionally, if the parameter in the 1830** argument list is a NULL pointer, %Q substitutes the text "NULL" (without 1831** single quotes) in place of the %Q option. So, for example, one could say: 1832** 1833** <blockquote><pre> 1834** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText); 1835** sqlite3_exec(db, zSQL, 0, 0, 0); 1836** sqlite3_free(zSQL); 1837** </pre></blockquote> 1838** 1839** The code above will render a correct SQL statement in the zSQL 1840** variable even if the zText variable is a NULL pointer. 1841** 1842** The "%z" formatting option works exactly like "%s" with the 1843** addition that after the string has been read and copied into 1844** the result, [sqlite3_free()] is called on the input string. {END} 1845** 1846** INVARIANTS: 1847** 1848** {H17403} The [sqlite3_mprintf()] and [sqlite3_vmprintf()] interfaces 1849** return either pointers to zero-terminated UTF-8 strings held in 1850** memory obtained from [sqlite3_malloc()] or NULL pointers if 1851** a call to [sqlite3_malloc()] fails. 1852** 1853** {H17406} The [sqlite3_snprintf()] interface writes a zero-terminated 1854** UTF-8 string into the buffer pointed to by the second parameter 1855** provided that the first parameter is greater than zero. 1856** 1857** {H17407} The [sqlite3_snprintf()] interface does not write slots of 1858** its output buffer (the second parameter) outside the range 1859** of 0 through N-1 (where N is the first parameter) 1860** regardless of the length of the string 1861** requested by the format specification. 1862*/ 1863char *sqlite3_mprintf(const char*,...); 1864char *sqlite3_vmprintf(const char*, va_list); 1865char *sqlite3_snprintf(int,char*,const char*, ...); 1866 1867/* 1868** CAPI3REF: Memory Allocation Subsystem {H17300} <S20000> 1869** 1870** The SQLite core uses these three routines for all of its own 1871** internal memory allocation needs. "Core" in the previous sentence 1872** does not include operating-system specific VFS implementation. The 1873** Windows VFS uses native malloc() and free() for some operations. 1874** 1875** The sqlite3_malloc() routine returns a pointer to a block 1876** of memory at least N bytes in length, where N is the parameter. 1877** If sqlite3_malloc() is unable to obtain sufficient free 1878** memory, it returns a NULL pointer. If the parameter N to 1879** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns 1880** a NULL pointer. 1881** 1882** Calling sqlite3_free() with a pointer previously returned 1883** by sqlite3_malloc() or sqlite3_realloc() releases that memory so 1884** that it might be reused. The sqlite3_free() routine is 1885** a no-op if is called with a NULL pointer. Passing a NULL pointer 1886** to sqlite3_free() is harmless. After being freed, memory 1887** should neither be read nor written. Even reading previously freed 1888** memory might result in a segmentation fault or other severe error. 1889** Memory corruption, a segmentation fault, or other severe error 1890** might result if sqlite3_free() is called with a non-NULL pointer that 1891** was not obtained from sqlite3_malloc() or sqlite3_free(). 1892** 1893** The sqlite3_realloc() interface attempts to resize a 1894** prior memory allocation to be at least N bytes, where N is the 1895** second parameter. The memory allocation to be resized is the first 1896** parameter. If the first parameter to sqlite3_realloc() 1897** is a NULL pointer then its behavior is identical to calling 1898** sqlite3_malloc(N) where N is the second parameter to sqlite3_realloc(). 1899** If the second parameter to sqlite3_realloc() is zero or 1900** negative then the behavior is exactly the same as calling 1901** sqlite3_free(P) where P is the first parameter to sqlite3_realloc(). 1902** sqlite3_realloc() returns a pointer to a memory allocation 1903** of at least N bytes in size or NULL if sufficient memory is unavailable. 1904** If M is the size of the prior allocation, then min(N,M) bytes 1905** of the prior allocation are copied into the beginning of buffer returned 1906** by sqlite3_realloc() and the prior allocation is freed. 1907** If sqlite3_realloc() returns NULL, then the prior allocation 1908** is not freed. 1909** 1910** The memory returned by sqlite3_malloc() and sqlite3_realloc() 1911** is always aligned to at least an 8 byte boundary. {END} 1912** 1913** The default implementation of the memory allocation subsystem uses 1914** the malloc(), realloc() and free() provided by the standard C library. 1915** {H17382} However, if SQLite is compiled with the 1916** SQLITE_MEMORY_SIZE=<i>NNN</i> C preprocessor macro (where <i>NNN</i> 1917** is an integer), then SQLite create a static array of at least 1918** <i>NNN</i> bytes in size and uses that array for all of its dynamic 1919** memory allocation needs. {END} Additional memory allocator options 1920** may be added in future releases. 1921** 1922** In SQLite version 3.5.0 and 3.5.1, it was possible to define 1923** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in 1924** implementation of these routines to be omitted. That capability 1925** is no longer provided. Only built-in memory allocators can be used. 1926** 1927** The Windows OS interface layer calls 1928** the system malloc() and free() directly when converting 1929** filenames between the UTF-8 encoding used by SQLite 1930** and whatever filename encoding is used by the particular Windows 1931** installation. Memory allocation errors are detected, but 1932** they are reported back as [SQLITE_CANTOPEN] or 1933** [SQLITE_IOERR] rather than [SQLITE_NOMEM]. 1934** 1935** INVARIANTS: 1936** 1937** {H17303} The [sqlite3_malloc(N)] interface returns either a pointer to 1938** a newly checked-out block of at least N bytes of memory 1939** that is 8-byte aligned, or it returns NULL if it is unable 1940** to fulfill the request. 1941** 1942** {H17304} The [sqlite3_malloc(N)] interface returns a NULL pointer if 1943** N is less than or equal to zero. 1944** 1945** {H17305} The [sqlite3_free(P)] interface releases memory previously 1946** returned from [sqlite3_malloc()] or [sqlite3_realloc()], 1947** making it available for reuse. 1948** 1949** {H17306} A call to [sqlite3_free(NULL)] is a harmless no-op. 1950** 1951** {H17310} A call to [sqlite3_realloc(0,N)] is equivalent to a call 1952** to [sqlite3_malloc(N)]. 1953** 1954** {H17312} A call to [sqlite3_realloc(P,0)] is equivalent to a call 1955** to [sqlite3_free(P)]. 1956** 1957** {H17315} The SQLite core uses [sqlite3_malloc()], [sqlite3_realloc()], 1958** and [sqlite3_free()] for all of its memory allocation and 1959** deallocation needs. 1960** 1961** {H17318} The [sqlite3_realloc(P,N)] interface returns either a pointer 1962** to a block of checked-out memory of at least N bytes in size 1963** that is 8-byte aligned, or a NULL pointer. 1964** 1965** {H17321} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first 1966** copies the first K bytes of content from P into the newly 1967** allocated block, where K is the lesser of N and the size of 1968** the buffer P. 1969** 1970** {H17322} When [sqlite3_realloc(P,N)] returns a non-NULL pointer, it first 1971** releases the buffer P. 1972** 1973** {H17323} When [sqlite3_realloc(P,N)] returns NULL, the buffer P is 1974** not modified or released. 1975** 1976** ASSUMPTIONS: 1977** 1978** {A17350} The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] 1979** must be either NULL or else pointers obtained from a prior 1980** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have 1981** not yet been released. 1982** 1983** {A17351} The application must not read or write any part of 1984** a block of memory after it has been released using 1985** [sqlite3_free()] or [sqlite3_realloc()]. 1986*/ 1987void *sqlite3_malloc(int); 1988void *sqlite3_realloc(void*, int); 1989void sqlite3_free(void*); 1990 1991/* 1992** CAPI3REF: Memory Allocator Statistics {H17370} <S30210> 1993** 1994** SQLite provides these two interfaces for reporting on the status 1995** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] 1996** routines, which form the built-in memory allocation subsystem. 1997** 1998** INVARIANTS: 1999** 2000** {H17371} The [sqlite3_memory_used()] routine returns the number of bytes 2001** of memory currently outstanding (malloced but not freed). 2002** 2003** {H17373} The [sqlite3_memory_highwater()] routine returns the maximum 2004** value of [sqlite3_memory_used()] since the high-water mark 2005** was last reset. 2006** 2007** {H17374} The values returned by [sqlite3_memory_used()] and 2008** [sqlite3_memory_highwater()] include any overhead 2009** added by SQLite in its implementation of [sqlite3_malloc()], 2010** but not overhead added by the any underlying system library 2011** routines that [sqlite3_malloc()] may call. 2012** 2013** {H17375} The memory high-water mark is reset to the current value of 2014** [sqlite3_memory_used()] if and only if the parameter to 2015** [sqlite3_memory_highwater()] is true. The value returned 2016** by [sqlite3_memory_highwater(1)] is the high-water mark 2017** prior to the reset. 2018*/ 2019sqlite3_int64 sqlite3_memory_used(void); 2020sqlite3_int64 sqlite3_memory_highwater(int resetFlag); 2021 2022/* 2023** CAPI3REF: Pseudo-Random Number Generator {H17390} <S20000> 2024** 2025** SQLite contains a high-quality pseudo-random number generator (PRNG) used to 2026** select random ROWIDs when inserting new records into a table that 2027** already uses the largest possible ROWID. The PRNG is also used for 2028** the build-in random() and randomblob() SQL functions. This interface allows 2029** applications to access the same PRNG for other purposes. 2030** 2031** A call to this routine stores N bytes of randomness into buffer P. 2032** 2033** The first time this routine is invoked (either internally or by 2034** the application) the PRNG is seeded using randomness obtained 2035** from the xRandomness method of the default [sqlite3_vfs] object. 2036** On all subsequent invocations, the pseudo-randomness is generated 2037** internally and without recourse to the [sqlite3_vfs] xRandomness 2038** method. 2039** 2040** INVARIANTS: 2041** 2042** {H17392} The [sqlite3_randomness(N,P)] interface writes N bytes of 2043** high-quality pseudo-randomness into buffer P. 2044*/ 2045void sqlite3_randomness(int N, void *P); 2046 2047/* 2048** CAPI3REF: Compile-Time Authorization Callbacks {H12500} <S70100> 2049** 2050** This routine registers a authorizer callback with a particular 2051** [database connection], supplied in the first argument. 2052** The authorizer callback is invoked as SQL statements are being compiled 2053** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], 2054** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. At various 2055** points during the compilation process, as logic is being created 2056** to perform various actions, the authorizer callback is invoked to 2057** see if those actions are allowed. The authorizer callback should 2058** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the 2059** specific action but allow the SQL statement to continue to be 2060** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be 2061** rejected with an error. If the authorizer callback returns 2062** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] 2063** then the [sqlite3_prepare_v2()] or equivalent call that triggered 2064** the authorizer will fail with an error message. 2065** 2066** When the callback returns [SQLITE_OK], that means the operation 2067** requested is ok. When the callback returns [SQLITE_DENY], the 2068** [sqlite3_prepare_v2()] or equivalent call that triggered the 2069** authorizer will fail with an error message explaining that 2070** access is denied. If the authorizer code is [SQLITE_READ] 2071** and the callback returns [SQLITE_IGNORE] then the 2072** [prepared statement] statement is constructed to substitute 2073** a NULL value in place of the table column that would have 2074** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] 2075** return can be used to deny an untrusted user access to individual 2076** columns of a table. 2077** 2078** The first parameter to the authorizer callback is a copy of the third 2079** parameter to the sqlite3_set_authorizer() interface. The second parameter 2080** to the callback is an integer [SQLITE_COPY | action code] that specifies 2081** the particular action to be authorized. The third through sixth parameters 2082** to the callback are zero-terminated strings that contain additional 2083** details about the action to be authorized. 2084** 2085** An authorizer is used when [sqlite3_prepare | preparing] 2086** SQL statements from an untrusted source, to ensure that the SQL statements 2087** do not try to access data they are not allowed to see, or that they do not 2088** try to execute malicious statements that damage the database. For 2089** example, an application may allow a user to enter arbitrary 2090** SQL queries for evaluation by a database. But the application does 2091** not want the user to be able to make arbitrary changes to the 2092** database. An authorizer could then be put in place while the 2093** user-entered SQL is being [sqlite3_prepare | prepared] that 2094** disallows everything except [SELECT] statements. 2095** 2096** Applications that need to process SQL from untrusted sources 2097** might also consider lowering resource limits using [sqlite3_limit()] 2098** and limiting database size using the [max_page_count] [PRAGMA] 2099** in addition to using an authorizer. 2100** 2101** Only a single authorizer can be in place on a database connection 2102** at a time. Each call to sqlite3_set_authorizer overrides the 2103** previous call. Disable the authorizer by installing a NULL callback. 2104** The authorizer is disabled by default. 2105** 2106** When [sqlite3_prepare_v2()] is used to prepare a statement, the 2107** statement might be reprepared during [sqlite3_step()] due to a 2108** schema change. Hence, the application should ensure that the 2109** correct authorizer callback remains in place during the [sqlite3_step()]. 2110** 2111** Note that the authorizer callback is invoked only during 2112** [sqlite3_prepare()] or its variants. Authorization is not 2113** performed during statement evaluation in [sqlite3_step()]. 2114** 2115** INVARIANTS: 2116** 2117** {H12501} The [sqlite3_set_authorizer(D,...)] interface registers a 2118** authorizer callback with database connection D. 2119** 2120** {H12502} The authorizer callback is invoked as SQL statements are 2121** being parseed and compiled. 2122** 2123** {H12503} If the authorizer callback returns any value other than 2124** [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY], then 2125** the application interface call that caused 2126** the authorizer callback to run shall fail with an 2127** [SQLITE_ERROR] error code and an appropriate error message. 2128** 2129** {H12504} When the authorizer callback returns [SQLITE_OK], the operation 2130** described is processed normally. 2131** 2132** {H12505} When the authorizer callback returns [SQLITE_DENY], the 2133** application interface call that caused the 2134** authorizer callback to run shall fail 2135** with an [SQLITE_ERROR] error code and an error message 2136** explaining that access is denied. 2137** 2138** {H12506} If the authorizer code (the 2nd parameter to the authorizer 2139** callback) is [SQLITE_READ] and the authorizer callback returns 2140** [SQLITE_IGNORE], then the prepared statement is constructed to 2141** insert a NULL value in place of the table column that would have 2142** been read if [SQLITE_OK] had been returned. 2143** 2144** {H12507} If the authorizer code (the 2nd parameter to the authorizer 2145** callback) is anything other than [SQLITE_READ], then 2146** a return of [SQLITE_IGNORE] has the same effect as [SQLITE_DENY]. 2147** 2148** {H12510} The first parameter to the authorizer callback is a copy of 2149** the third parameter to the [sqlite3_set_authorizer()] interface. 2150** 2151** {H12511} The second parameter to the callback is an integer 2152** [SQLITE_COPY | action code] that specifies the particular action 2153** to be authorized. 2154** 2155** {H12512} The third through sixth parameters to the callback are 2156** zero-terminated strings that contain 2157** additional details about the action to be authorized. 2158** 2159** {H12520} Each call to [sqlite3_set_authorizer()] overrides 2160** any previously installed authorizer. 2161** 2162** {H12521} A NULL authorizer means that no authorization 2163** callback is invoked. 2164** 2165** {H12522} The default authorizer is NULL. 2166*/ 2167int sqlite3_set_authorizer( 2168 sqlite3*, 2169 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 2170 void *pUserData 2171); 2172 2173/* 2174** CAPI3REF: Authorizer Return Codes {H12590} <H12500> 2175** 2176** The [sqlite3_set_authorizer | authorizer callback function] must 2177** return either [SQLITE_OK] or one of these two constants in order 2178** to signal SQLite whether or not the action is permitted. See the 2179** [sqlite3_set_authorizer | authorizer documentation] for additional 2180** information. 2181*/ 2182#define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 2183#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 2184 2185/* 2186** CAPI3REF: Authorizer Action Codes {H12550} <H12500> 2187** 2188** The [sqlite3_set_authorizer()] interface registers a callback function 2189** that is invoked to authorize certain SQL statement actions. The 2190** second parameter to the callback is an integer code that specifies 2191** what action is being authorized. These are the integer action codes that 2192** the authorizer callback may be passed. 2193** 2194** These action code values signify what kind of operation is to be 2195** authorized. The 3rd and 4th parameters to the authorization 2196** callback function will be parameters or NULL depending on which of these 2197** codes is used as the second parameter. The 5th parameter to the 2198** authorizer callback is the name of the database ("main", "temp", 2199** etc.) if applicable. The 6th parameter to the authorizer callback 2200** is the name of the inner-most trigger or view that is responsible for 2201** the access attempt or NULL if this access attempt is directly from 2202** top-level SQL code. 2203** 2204** INVARIANTS: 2205** 2206** {H12551} The second parameter to an 2207** [sqlite3_set_authorizer | authorizer callback] shall be an integer 2208** [SQLITE_COPY | authorizer code] that specifies what action 2209** is being authorized. 2210** 2211** {H12552} The 3rd and 4th parameters to the 2212** [sqlite3_set_authorizer | authorization callback] 2213** shall be parameters or NULL depending on which 2214** [SQLITE_COPY | authorizer code] is used as the second parameter. 2215** 2216** {H12553} The 5th parameter to the 2217** [sqlite3_set_authorizer | authorizer callback] shall be the name 2218** of the database (example: "main", "temp", etc.) if applicable. 2219** 2220** {H12554} The 6th parameter to the 2221** [sqlite3_set_authorizer | authorizer callback] shall be the name 2222** of the inner-most trigger or view that is responsible for 2223** the access attempt or NULL if this access attempt is directly from 2224** top-level SQL code. 2225*/ 2226/******************************************* 3rd ************ 4th ***********/ 2227#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 2228#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 2229#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 2230#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 2231#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 2232#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 2233#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 2234#define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 2235#define SQLITE_DELETE 9 /* Table Name NULL */ 2236#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 2237#define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 2238#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 2239#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 2240#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 2241#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 2242#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 2243#define SQLITE_DROP_VIEW 17 /* View Name NULL */ 2244#define SQLITE_INSERT 18 /* Table Name NULL */ 2245#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 2246#define SQLITE_READ 20 /* Table Name Column Name */ 2247#define SQLITE_SELECT 21 /* NULL NULL */ 2248#define SQLITE_TRANSACTION 22 /* NULL NULL */ 2249#define SQLITE_UPDATE 23 /* Table Name Column Name */ 2250#define SQLITE_ATTACH 24 /* Filename NULL */ 2251#define SQLITE_DETACH 25 /* Database Name NULL */ 2252#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ 2253#define SQLITE_REINDEX 27 /* Index Name NULL */ 2254#define SQLITE_ANALYZE 28 /* Table Name NULL */ 2255#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ 2256#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ 2257#define SQLITE_FUNCTION 31 /* Function Name NULL */ 2258#define SQLITE_COPY 0 /* No longer used */ 2259 2260/* 2261** CAPI3REF: Tracing And Profiling Functions {H12280} <S60400> 2262** EXPERIMENTAL 2263** 2264** These routines register callback functions that can be used for 2265** tracing and profiling the execution of SQL statements. 2266** 2267** The callback function registered by sqlite3_trace() is invoked at 2268** various times when an SQL statement is being run by [sqlite3_step()]. 2269** The callback returns a UTF-8 rendering of the SQL statement text 2270** as the statement first begins executing. Additional callbacks occur 2271** as each triggered subprogram is entered. The callbacks for triggers 2272** contain a UTF-8 SQL comment that identifies the trigger. 2273** 2274** The callback function registered by sqlite3_profile() is invoked 2275** as each SQL statement finishes. The profile callback contains 2276** the original statement text and an estimate of wall-clock time 2277** of how long that statement took to run. 2278** 2279** INVARIANTS: 2280** 2281** {H12281} The callback function registered by [sqlite3_trace()] 2282** shall be invoked 2283** whenever an SQL statement first begins to execute and 2284** whenever a trigger subprogram first begins to run. 2285** 2286** {H12282} Each call to [sqlite3_trace()] shall override the previously 2287** registered trace callback. 2288** 2289** {H12283} A NULL trace callback shall disable tracing. 2290** 2291** {H12284} The first argument to the trace callback shall be a copy of 2292** the pointer which was the 3rd argument to [sqlite3_trace()]. 2293** 2294** {H12285} The second argument to the trace callback is a 2295** zero-terminated UTF-8 string containing the original text 2296** of the SQL statement as it was passed into [sqlite3_prepare_v2()] 2297** or the equivalent, or an SQL comment indicating the beginning 2298** of a trigger subprogram. 2299** 2300** {H12287} The callback function registered by [sqlite3_profile()] is invoked 2301** as each SQL statement finishes. 2302** 2303** {H12288} The first parameter to the profile callback is a copy of 2304** the 3rd parameter to [sqlite3_profile()]. 2305** 2306** {H12289} The second parameter to the profile callback is a 2307** zero-terminated UTF-8 string that contains the complete text of 2308** the SQL statement as it was processed by [sqlite3_prepare_v2()] 2309** or the equivalent. 2310** 2311** {H12290} The third parameter to the profile callback is an estimate 2312** of the number of nanoseconds of wall-clock time required to 2313** run the SQL statement from start to finish. 2314*/ 2315SQLITE_EXPERIMENTAL void *sqlite3_trace(sqlite3*, void(*xTrace)(void*,const char*), void*); 2316SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*, 2317 void(*xProfile)(void*,const char*,sqlite3_uint64), void*); 2318 2319/* 2320** CAPI3REF: Query Progress Callbacks {H12910} <S60400> 2321** 2322** This routine configures a callback function - the 2323** progress callback - that is invoked periodically during long 2324** running calls to [sqlite3_exec()], [sqlite3_step()] and 2325** [sqlite3_get_table()]. An example use for this 2326** interface is to keep a GUI updated during a large query. 2327** 2328** If the progress callback returns non-zero, the operation is 2329** interrupted. This feature can be used to implement a 2330** "Cancel" button on a GUI dialog box. 2331** 2332** INVARIANTS: 2333** 2334** {H12911} The callback function registered by sqlite3_progress_handler() 2335** is invoked periodically during long running calls to 2336** [sqlite3_step()]. 2337** 2338** {H12912} The progress callback is invoked once for every N virtual 2339** machine opcodes, where N is the second argument to 2340** the [sqlite3_progress_handler()] call that registered 2341** the callback. If N is less than 1, sqlite3_progress_handler() 2342** acts as if a NULL progress handler had been specified. 2343** 2344** {H12913} The progress callback itself is identified by the third 2345** argument to sqlite3_progress_handler(). 2346** 2347** {H12914} The fourth argument to sqlite3_progress_handler() is a 2348** void pointer passed to the progress callback 2349** function each time it is invoked. 2350** 2351** {H12915} If a call to [sqlite3_step()] results in fewer than N opcodes 2352** being executed, then the progress callback is never invoked. 2353** 2354** {H12916} Every call to [sqlite3_progress_handler()] 2355** overwrites any previously registered progress handler. 2356** 2357** {H12917} If the progress handler callback is NULL then no progress 2358** handler is invoked. 2359** 2360** {H12918} If the progress callback returns a result other than 0, then 2361** the behavior is a if [sqlite3_interrupt()] had been called. 2362** <S30500> 2363*/ 2364void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); 2365 2366/* 2367** CAPI3REF: Opening A New Database Connection {H12700} <S40200> 2368** 2369** These routines open an SQLite database file whose name is given by the 2370** filename argument. The filename argument is interpreted as UTF-8 for 2371** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte 2372** order for sqlite3_open16(). A [database connection] handle is usually 2373** returned in *ppDb, even if an error occurs. The only exception is that 2374** if SQLite is unable to allocate memory to hold the [sqlite3] object, 2375** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] 2376** object. If the database is opened (and/or created) successfully, then 2377** [SQLITE_OK] is returned. Otherwise an [error code] is returned. The 2378** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain 2379** an English language description of the error. 2380** 2381** The default encoding for the database will be UTF-8 if 2382** sqlite3_open() or sqlite3_open_v2() is called and 2383** UTF-16 in the native byte order if sqlite3_open16() is used. 2384** 2385** Whether or not an error occurs when it is opened, resources 2386** associated with the [database connection] handle should be released by 2387** passing it to [sqlite3_close()] when it is no longer required. 2388** 2389** The sqlite3_open_v2() interface works like sqlite3_open() 2390** except that it accepts two additional parameters for additional control 2391** over the new database connection. The flags parameter can take one of 2392** the following three values, optionally combined with the 2393** [SQLITE_OPEN_NOMUTEX] or [SQLITE_OPEN_FULLMUTEX] flags: 2394** 2395** <dl> 2396** <dt>[SQLITE_OPEN_READONLY]</dt> 2397** <dd>The database is opened in read-only mode. If the database does not 2398** already exist, an error is returned.</dd> 2399** 2400** <dt>[SQLITE_OPEN_READWRITE]</dt> 2401** <dd>The database is opened for reading and writing if possible, or reading 2402** only if the file is write protected by the operating system. In either 2403** case the database must already exist, otherwise an error is returned.</dd> 2404** 2405** <dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> 2406** <dd>The database is opened for reading and writing, and is creates it if 2407** it does not already exist. This is the behavior that is always used for 2408** sqlite3_open() and sqlite3_open16().</dd> 2409** </dl> 2410** 2411** If the 3rd parameter to sqlite3_open_v2() is not one of the 2412** combinations shown above or one of the combinations shown above combined 2413** with the [SQLITE_OPEN_NOMUTEX] or [SQLITE_OPEN_FULLMUTEX] flags, 2414** then the behavior is undefined. 2415** 2416** If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection 2417** opens in the multi-thread [threading mode] as long as the single-thread 2418** mode has not been set at compile-time or start-time. If the 2419** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens 2420** in the serialized [threading mode] unless single-thread was 2421** previously selected at compile-time or start-time. 2422** 2423** If the filename is ":memory:", then a private, temporary in-memory database 2424** is created for the connection. This in-memory database will vanish when 2425** the database connection is closed. Future versions of SQLite might 2426** make use of additional special filenames that begin with the ":" character. 2427** It is recommended that when a database filename actually does begin with 2428** a ":" character you should prefix the filename with a pathname such as 2429** "./" to avoid ambiguity. 2430** 2431** If the filename is an empty string, then a private, temporary 2432** on-disk database will be created. This private database will be 2433** automatically deleted as soon as the database connection is closed. 2434** 2435** The fourth parameter to sqlite3_open_v2() is the name of the 2436** [sqlite3_vfs] object that defines the operating system interface that 2437** the new database connection should use. If the fourth parameter is 2438** a NULL pointer then the default [sqlite3_vfs] object is used. 2439** 2440** <b>Note to Windows users:</b> The encoding used for the filename argument 2441** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever 2442** codepage is currently defined. Filenames containing international 2443** characters must be converted to UTF-8 prior to passing them into 2444** sqlite3_open() or sqlite3_open_v2(). 2445** 2446** INVARIANTS: 2447** 2448** {H12701} The [sqlite3_open()], [sqlite3_open16()], and 2449** [sqlite3_open_v2()] interfaces create a new 2450** [database connection] associated with 2451** the database file given in their first parameter. 2452** 2453** {H12702} The filename argument is interpreted as UTF-8 2454** for [sqlite3_open()] and [sqlite3_open_v2()] and as UTF-16 2455** in the native byte order for [sqlite3_open16()]. 2456** 2457** {H12703} A successful invocation of [sqlite3_open()], [sqlite3_open16()], 2458** or [sqlite3_open_v2()] writes a pointer to a new 2459** [database connection] into *ppDb. 2460** 2461** {H12704} The [sqlite3_open()], [sqlite3_open16()], and 2462** [sqlite3_open_v2()] interfaces return [SQLITE_OK] upon success, 2463** or an appropriate [error code] on failure. 2464** 2465** {H12706} The default text encoding for a new database created using 2466** [sqlite3_open()] or [sqlite3_open_v2()] will be UTF-8. 2467** 2468** {H12707} The default text encoding for a new database created using 2469** [sqlite3_open16()] will be UTF-16. 2470** 2471** {H12709} The [sqlite3_open(F,D)] interface is equivalent to 2472** [sqlite3_open_v2(F,D,G,0)] where the G parameter is 2473** [SQLITE_OPEN_READWRITE]|[SQLITE_OPEN_CREATE]. 2474** 2475** {H12711} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the 2476** bit value [SQLITE_OPEN_READONLY] then the database is opened 2477** for reading only. 2478** 2479** {H12712} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the 2480** bit value [SQLITE_OPEN_READWRITE] then the database is opened 2481** reading and writing if possible, or for reading only if the 2482** file is write protected by the operating system. 2483** 2484** {H12713} If the G parameter to [sqlite3_open_v2(F,D,G,V)] omits the 2485** bit value [SQLITE_OPEN_CREATE] and the database does not 2486** previously exist, an error is returned. 2487** 2488** {H12714} If the G parameter to [sqlite3_open_v2(F,D,G,V)] contains the 2489** bit value [SQLITE_OPEN_CREATE] and the database does not 2490** previously exist, then an attempt is made to create and 2491** initialize the database. 2492** 2493** {H12717} If the filename argument to [sqlite3_open()], [sqlite3_open16()], 2494** or [sqlite3_open_v2()] is ":memory:", then an private, 2495** ephemeral, in-memory database is created for the connection. 2496** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required 2497** in sqlite3_open_v2()?</todo> 2498** 2499** {H12719} If the filename is NULL or an empty string, then a private, 2500** ephemeral on-disk database will be created. 2501** <todo>Is SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE required 2502** in sqlite3_open_v2()?</todo> 2503** 2504** {H12721} The [database connection] created by [sqlite3_open_v2(F,D,G,V)] 2505** will use the [sqlite3_vfs] object identified by the V parameter, 2506** or the default [sqlite3_vfs] object if V is a NULL pointer. 2507** 2508** {H12723} Two [database connections] will share a common cache if both were 2509** opened with the same VFS while [shared cache mode] was enabled and 2510** if both filenames compare equal using memcmp() after having been 2511** processed by the [sqlite3_vfs | xFullPathname] method of the VFS. 2512*/ 2513int sqlite3_open( 2514 const char *filename, /* Database filename (UTF-8) */ 2515 sqlite3 **ppDb /* OUT: SQLite db handle */ 2516); 2517int sqlite3_open16( 2518 const void *filename, /* Database filename (UTF-16) */ 2519 sqlite3 **ppDb /* OUT: SQLite db handle */ 2520); 2521int sqlite3_open_v2( 2522 const char *filename, /* Database filename (UTF-8) */ 2523 sqlite3 **ppDb, /* OUT: SQLite db handle */ 2524 int flags, /* Flags */ 2525 const char *zVfs /* Name of VFS module to use */ 2526); 2527 2528/* 2529** CAPI3REF: Error Codes And Messages {H12800} <S60200> 2530** 2531** The sqlite3_errcode() interface returns the numeric [result code] or 2532** [extended result code] for the most recent failed sqlite3_* API call 2533** associated with a [database connection]. If a prior API call failed 2534** but the most recent API call succeeded, the return value from 2535** sqlite3_errcode() is undefined. 2536** 2537** The sqlite3_errmsg() and sqlite3_errmsg16() return English-language 2538** text that describes the error, as either UTF-8 or UTF-16 respectively. 2539** Memory to hold the error message string is managed internally. 2540** The application does not need to worry about freeing the result. 2541** However, the error string might be overwritten or deallocated by 2542** subsequent calls to other SQLite interface functions. 2543** 2544** If an interface fails with SQLITE_MISUSE, that means the interface 2545** was invoked incorrectly by the application. In that case, the 2546** error code and message may or may not be set. 2547** 2548** INVARIANTS: 2549** 2550** {H12801} The [sqlite3_errcode(D)] interface returns the numeric 2551** [result code] or [extended result code] for the most recently 2552** failed interface call associated with the [database connection] D. 2553** 2554** {H12803} The [sqlite3_errmsg(D)] and [sqlite3_errmsg16(D)] 2555** interfaces return English-language text that describes 2556** the error in the mostly recently failed interface call, 2557** encoded as either UTF-8 or UTF-16 respectively. 2558** 2559** {H12807} The strings returned by [sqlite3_errmsg()] and [sqlite3_errmsg16()] 2560** are valid until the next SQLite interface call. 2561** 2562** {H12808} Calls to API routines that do not return an error code 2563** (example: [sqlite3_data_count()]) do not 2564** change the error code or message returned by 2565** [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()]. 2566** 2567** {H12809} Interfaces that are not associated with a specific 2568** [database connection] (examples: 2569** [sqlite3_mprintf()] or [sqlite3_enable_shared_cache()] 2570** do not change the values returned by 2571** [sqlite3_errcode()], [sqlite3_errmsg()], or [sqlite3_errmsg16()]. 2572*/ 2573int sqlite3_errcode(sqlite3 *db); 2574const char *sqlite3_errmsg(sqlite3*); 2575const void *sqlite3_errmsg16(sqlite3*); 2576 2577/* 2578** CAPI3REF: SQL Statement Object {H13000} <H13010> 2579** KEYWORDS: {prepared statement} {prepared statements} 2580** 2581** An instance of this object represents a single SQL statement. 2582** This object is variously known as a "prepared statement" or a 2583** "compiled SQL statement" or simply as a "statement". 2584** 2585** The life of a statement object goes something like this: 2586** 2587** <ol> 2588** <li> Create the object using [sqlite3_prepare_v2()] or a related 2589** function. 2590** <li> Bind values to [host parameters] using the sqlite3_bind_*() 2591** interfaces. 2592** <li> Run the SQL by calling [sqlite3_step()] one or more times. 2593** <li> Reset the statement using [sqlite3_reset()] then go back 2594** to step 2. Do this zero or more times. 2595** <li> Destroy the object using [sqlite3_finalize()]. 2596** </ol> 2597** 2598** Refer to documentation on individual methods above for additional 2599** information. 2600*/ 2601typedef struct sqlite3_stmt sqlite3_stmt; 2602 2603/* 2604** CAPI3REF: Run-time Limits {H12760} <S20600> 2605** 2606** This interface allows the size of various constructs to be limited 2607** on a connection by connection basis. The first parameter is the 2608** [database connection] whose limit is to be set or queried. The 2609** second parameter is one of the [limit categories] that define a 2610** class of constructs to be size limited. The third parameter is the 2611** new limit for that construct. The function returns the old limit. 2612** 2613** If the new limit is a negative number, the limit is unchanged. 2614** For the limit category of SQLITE_LIMIT_XYZ there is a hard upper 2615** bound set by a compile-time C preprocessor macro named SQLITE_MAX_XYZ. 2616** (The "_LIMIT_" in the name is changed to "_MAX_".) 2617** Attempts to increase a limit above its hard upper bound are 2618** silently truncated to the hard upper limit. 2619** 2620** Run time limits are intended for use in applications that manage 2621** both their own internal database and also databases that are controlled 2622** by untrusted external sources. An example application might be a 2623** webbrowser that has its own databases for storing history and 2624** separate databases controlled by JavaScript applications downloaded 2625** off the Internet. The internal databases can be given the 2626** large, default limits. Databases managed by external sources can 2627** be given much smaller limits designed to prevent a denial of service 2628** attack. Developers might also want to use the [sqlite3_set_authorizer()] 2629** interface to further control untrusted SQL. The size of the database 2630** created by an untrusted script can be contained using the 2631** [max_page_count] [PRAGMA]. 2632** 2633** New run-time limit categories may be added in future releases. 2634** 2635** INVARIANTS: 2636** 2637** {H12762} A successful call to [sqlite3_limit(D,C,V)] where V is 2638** positive changes the limit on the size of construct C in the 2639** [database connection] D to the lesser of V and the hard upper 2640** bound on the size of C that is set at compile-time. 2641** 2642** {H12766} A successful call to [sqlite3_limit(D,C,V)] where V is negative 2643** leaves the state of the [database connection] D unchanged. 2644** 2645** {H12769} A successful call to [sqlite3_limit(D,C,V)] returns the 2646** value of the limit on the size of construct C in the 2647** [database connection] D as it was prior to the call. 2648*/ 2649int sqlite3_limit(sqlite3*, int id, int newVal); 2650 2651/* 2652** CAPI3REF: Run-Time Limit Categories {H12790} <H12760> 2653** KEYWORDS: {limit category} {limit categories} 2654** 2655** These constants define various aspects of a [database connection] 2656** that can be limited in size by calls to [sqlite3_limit()]. 2657** The meanings of the various limits are as follows: 2658** 2659** <dl> 2660** <dt>SQLITE_LIMIT_LENGTH</dt> 2661** <dd>The maximum size of any string or BLOB or table row.<dd> 2662** 2663** <dt>SQLITE_LIMIT_SQL_LENGTH</dt> 2664** <dd>The maximum length of an SQL statement.</dd> 2665** 2666** <dt>SQLITE_LIMIT_COLUMN</dt> 2667** <dd>The maximum number of columns in a table definition or in the 2668** result set of a SELECT or the maximum number of columns in an index 2669** or in an ORDER BY or GROUP BY clause.</dd> 2670** 2671** <dt>SQLITE_LIMIT_EXPR_DEPTH</dt> 2672** <dd>The maximum depth of the parse tree on any expression.</dd> 2673** 2674** <dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> 2675** <dd>The maximum number of terms in a compound SELECT statement.</dd> 2676** 2677** <dt>SQLITE_LIMIT_VDBE_OP</dt> 2678** <dd>The maximum number of instructions in a virtual machine program 2679** used to implement an SQL statement.</dd> 2680** 2681** <dt>SQLITE_LIMIT_FUNCTION_ARG</dt> 2682** <dd>The maximum number of arguments on a function.</dd> 2683** 2684** <dt>SQLITE_LIMIT_ATTACHED</dt> 2685** <dd>The maximum number of attached databases.</dd> 2686** 2687** <dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> 2688** <dd>The maximum length of the pattern argument to the LIKE or 2689** GLOB operators.</dd> 2690** 2691** <dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> 2692** <dd>The maximum number of variables in an SQL statement that can 2693** be bound.</dd> 2694** </dl> 2695*/ 2696#define SQLITE_LIMIT_LENGTH 0 2697#define SQLITE_LIMIT_SQL_LENGTH 1 2698#define SQLITE_LIMIT_COLUMN 2 2699#define SQLITE_LIMIT_EXPR_DEPTH 3 2700#define SQLITE_LIMIT_COMPOUND_SELECT 4 2701#define SQLITE_LIMIT_VDBE_OP 5 2702#define SQLITE_LIMIT_FUNCTION_ARG 6 2703#define SQLITE_LIMIT_ATTACHED 7 2704#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 2705#define SQLITE_LIMIT_VARIABLE_NUMBER 9 2706 2707/* 2708** CAPI3REF: Compiling An SQL Statement {H13010} <S10000> 2709** KEYWORDS: {SQL statement compiler} 2710** 2711** To execute an SQL query, it must first be compiled into a byte-code 2712** program using one of these routines. 2713** 2714** The first argument, "db", is a [database connection] obtained from a 2715** prior call to [sqlite3_open()], [sqlite3_open_v2()] or [sqlite3_open16()]. 2716** 2717** The second argument, "zSql", is the statement to be compiled, encoded 2718** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2() 2719** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2() 2720** use UTF-16. 2721** 2722** If the nByte argument is less than zero, then zSql is read up to the 2723** first zero terminator. If nByte is non-negative, then it is the maximum 2724** number of bytes read from zSql. When nByte is non-negative, the 2725** zSql string ends at either the first '\000' or '\u0000' character or 2726** the nByte-th byte, whichever comes first. If the caller knows 2727** that the supplied string is nul-terminated, then there is a small 2728** performance advantage to be gained by passing an nByte parameter that 2729** is equal to the number of bytes in the input string <i>including</i> 2730** the nul-terminator bytes. 2731** 2732** *pzTail is made to point to the first byte past the end of the 2733** first SQL statement in zSql. These routines only compile the first 2734** statement in zSql, so *pzTail is left pointing to what remains 2735** uncompiled. 2736** 2737** *ppStmt is left pointing to a compiled [prepared statement] that can be 2738** executed using [sqlite3_step()]. If there is an error, *ppStmt is set 2739** to NULL. If the input text contains no SQL (if the input is an empty 2740** string or a comment) then *ppStmt is set to NULL. 2741** {A13018} The calling procedure is responsible for deleting the compiled 2742** SQL statement using [sqlite3_finalize()] after it has finished with it. 2743** 2744** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned. 2745** 2746** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are 2747** recommended for all new programs. The two older interfaces are retained 2748** for backwards compatibility, but their use is discouraged. 2749** In the "v2" interfaces, the prepared statement 2750** that is returned (the [sqlite3_stmt] object) contains a copy of the 2751** original SQL text. This causes the [sqlite3_step()] interface to 2752** behave a differently in two ways: 2753** 2754** <ol> 2755** <li> 2756** If the database schema changes, instead of returning [SQLITE_SCHEMA] as it 2757** always used to do, [sqlite3_step()] will automatically recompile the SQL 2758** statement and try to run it again. If the schema has changed in 2759** a way that makes the statement no longer valid, [sqlite3_step()] will still 2760** return [SQLITE_SCHEMA]. But unlike the legacy behavior, [SQLITE_SCHEMA] is 2761** now a fatal error. Calling [sqlite3_prepare_v2()] again will not make the 2762** error go away. Note: use [sqlite3_errmsg()] to find the text 2763** of the parsing error that results in an [SQLITE_SCHEMA] return. 2764** </li> 2765** 2766** <li> 2767** When an error occurs, [sqlite3_step()] will return one of the detailed 2768** [error codes] or [extended error codes]. The legacy behavior was that 2769** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code 2770** and you would have to make a second call to [sqlite3_reset()] in order 2771** to find the underlying cause of the problem. With the "v2" prepare 2772** interfaces, the underlying reason for the error is returned immediately. 2773** </li> 2774** </ol> 2775** 2776** INVARIANTS: 2777** 2778** {H13011} The [sqlite3_prepare(db,zSql,...)] and 2779** [sqlite3_prepare_v2(db,zSql,...)] interfaces interpret the 2780** text in their zSql parameter as UTF-8. 2781** 2782** {H13012} The [sqlite3_prepare16(db,zSql,...)] and 2783** [sqlite3_prepare16_v2(db,zSql,...)] interfaces interpret the 2784** text in their zSql parameter as UTF-16 in the native byte order. 2785** 2786** {H13013} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)] 2787** and its variants is less than zero, the SQL text is 2788** read from zSql is read up to the first zero terminator. 2789** 2790** {H13014} If the nByte argument to [sqlite3_prepare_v2(db,zSql,nByte,...)] 2791** and its variants is non-negative, then at most nBytes bytes of 2792** SQL text is read from zSql. 2793** 2794** {H13015} In [sqlite3_prepare_v2(db,zSql,N,P,pzTail)] and its variants 2795** if the zSql input text contains more than one SQL statement 2796** and pzTail is not NULL, then *pzTail is made to point to the 2797** first byte past the end of the first SQL statement in zSql. 2798** <todo>What does *pzTail point to if there is one statement?</todo> 2799** 2800** {H13016} A successful call to [sqlite3_prepare_v2(db,zSql,N,ppStmt,...)] 2801** or one of its variants writes into *ppStmt a pointer to a new 2802** [prepared statement] or a pointer to NULL if zSql contains 2803** nothing other than whitespace or comments. 2804** 2805** {H13019} The [sqlite3_prepare_v2()] interface and its variants return 2806** [SQLITE_OK] or an appropriate [error code] upon failure. 2807** 2808** {H13021} Before [sqlite3_prepare(db,zSql,nByte,ppStmt,pzTail)] or its 2809** variants returns an error (any value other than [SQLITE_OK]), 2810** they first set *ppStmt to NULL. 2811*/ 2812int sqlite3_prepare( 2813 sqlite3 *db, /* Database handle */ 2814 const char *zSql, /* SQL statement, UTF-8 encoded */ 2815 int nByte, /* Maximum length of zSql in bytes. */ 2816 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 2817 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 2818); 2819int sqlite3_prepare_v2( 2820 sqlite3 *db, /* Database handle */ 2821 const char *zSql, /* SQL statement, UTF-8 encoded */ 2822 int nByte, /* Maximum length of zSql in bytes. */ 2823 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 2824 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 2825); 2826int sqlite3_prepare16( 2827 sqlite3 *db, /* Database handle */ 2828 const void *zSql, /* SQL statement, UTF-16 encoded */ 2829 int nByte, /* Maximum length of zSql in bytes. */ 2830 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 2831 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 2832); 2833int sqlite3_prepare16_v2( 2834 sqlite3 *db, /* Database handle */ 2835 const void *zSql, /* SQL statement, UTF-16 encoded */ 2836 int nByte, /* Maximum length of zSql in bytes. */ 2837 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 2838 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 2839); 2840 2841/* 2842** CAPIREF: Retrieving Statement SQL {H13100} <H13000> 2843** 2844** This interface can be used to retrieve a saved copy of the original 2845** SQL text used to create a [prepared statement] if that statement was 2846** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()]. 2847** 2848** INVARIANTS: 2849** 2850** {H13101} If the [prepared statement] passed as the argument to 2851** [sqlite3_sql()] was compiled using either [sqlite3_prepare_v2()] or 2852** [sqlite3_prepare16_v2()], then [sqlite3_sql()] returns 2853** a pointer to a zero-terminated string containing a UTF-8 rendering 2854** of the original SQL statement. 2855** 2856** {H13102} If the [prepared statement] passed as the argument to 2857** [sqlite3_sql()] was compiled using either [sqlite3_prepare()] or 2858** [sqlite3_prepare16()], then [sqlite3_sql()] returns a NULL pointer. 2859** 2860** {H13103} The string returned by [sqlite3_sql(S)] is valid until the 2861** [prepared statement] S is deleted using [sqlite3_finalize(S)]. 2862*/ 2863const char *sqlite3_sql(sqlite3_stmt *pStmt); 2864 2865/* 2866** CAPI3REF: Dynamically Typed Value Object {H15000} <S20200> 2867** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} 2868** 2869** SQLite uses the sqlite3_value object to represent all values 2870** that can be stored in a database table. SQLite uses dynamic typing 2871** for the values it stores. Values stored in sqlite3_value objects 2872** can be integers, floating point values, strings, BLOBs, or NULL. 2873** 2874** An sqlite3_value object may be either "protected" or "unprotected". 2875** Some interfaces require a protected sqlite3_value. Other interfaces 2876** will accept either a protected or an unprotected sqlite3_value. 2877** Every interface that accepts sqlite3_value arguments specifies 2878** whether or not it requires a protected sqlite3_value. 2879** 2880** The terms "protected" and "unprotected" refer to whether or not 2881** a mutex is held. A internal mutex is held for a protected 2882** sqlite3_value object but no mutex is held for an unprotected 2883** sqlite3_value object. If SQLite is compiled to be single-threaded 2884** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) 2885** or if SQLite is run in one of reduced mutex modes 2886** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] 2887** then there is no distinction between protected and unprotected 2888** sqlite3_value objects and they can be used interchangeably. However, 2889** for maximum code portability it is recommended that applications 2890** still make the distinction between between protected and unprotected 2891** sqlite3_value objects even when not strictly required. 2892** 2893** The sqlite3_value objects that are passed as parameters into the 2894** implementation of [application-defined SQL functions] are protected. 2895** The sqlite3_value object returned by 2896** [sqlite3_column_value()] is unprotected. 2897** Unprotected sqlite3_value objects may only be used with 2898** [sqlite3_result_value()] and [sqlite3_bind_value()]. 2899** The [sqlite3_value_blob | sqlite3_value_type()] family of 2900** interfaces require protected sqlite3_value objects. 2901*/ 2902typedef struct Mem sqlite3_value; 2903 2904/* 2905** CAPI3REF: SQL Function Context Object {H16001} <S20200> 2906** 2907** The context in which an SQL function executes is stored in an 2908** sqlite3_context object. A pointer to an sqlite3_context object 2909** is always first parameter to [application-defined SQL functions]. 2910** The application-defined SQL function implementation will pass this 2911** pointer through into calls to [sqlite3_result_int | sqlite3_result()], 2912** [sqlite3_aggregate_context()], [sqlite3_user_data()], 2913** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], 2914** and/or [sqlite3_set_auxdata()]. 2915*/ 2916typedef struct sqlite3_context sqlite3_context; 2917 2918/* 2919** CAPI3REF: Binding Values To Prepared Statements {H13500} <S70300> 2920** KEYWORDS: {host parameter} {host parameters} {host parameter name} 2921** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} 2922** 2923** In the SQL strings input to [sqlite3_prepare_v2()] and its variants, 2924** literals may be replaced by a parameter in one of these forms: 2925** 2926** <ul> 2927** <li> ? 2928** <li> ?NNN 2929** <li> :VVV 2930** <li> @VVV 2931** <li> $VVV 2932** </ul> 2933** 2934** In the parameter forms shown above NNN is an integer literal, 2935** and VVV is an alpha-numeric parameter name. The values of these 2936** parameters (also called "host parameter names" or "SQL parameters") 2937** can be set using the sqlite3_bind_*() routines defined here. 2938** 2939** The first argument to the sqlite3_bind_*() routines is always 2940** a pointer to the [sqlite3_stmt] object returned from 2941** [sqlite3_prepare_v2()] or its variants. 2942** 2943** The second argument is the index of the SQL parameter to be set. 2944** The leftmost SQL parameter has an index of 1. When the same named 2945** SQL parameter is used more than once, second and subsequent 2946** occurrences have the same index as the first occurrence. 2947** The index for named parameters can be looked up using the 2948** [sqlite3_bind_parameter_index()] API if desired. The index 2949** for "?NNN" parameters is the value of NNN. 2950** The NNN value must be between 1 and the [sqlite3_limit()] 2951** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999). 2952** 2953** The third argument is the value to bind to the parameter. 2954** 2955** In those routines that have a fourth argument, its value is the 2956** number of bytes in the parameter. To be clear: the value is the 2957** number of <u>bytes</u> in the value, not the number of characters. 2958** If the fourth parameter is negative, the length of the string is 2959** the number of bytes up to the first zero terminator. 2960** 2961** The fifth argument to sqlite3_bind_blob(), sqlite3_bind_text(), and 2962** sqlite3_bind_text16() is a destructor used to dispose of the BLOB or 2963** string after SQLite has finished with it. If the fifth argument is 2964** the special value [SQLITE_STATIC], then SQLite assumes that the 2965** information is in static, unmanaged space and does not need to be freed. 2966** If the fifth argument has the value [SQLITE_TRANSIENT], then 2967** SQLite makes its own private copy of the data immediately, before 2968** the sqlite3_bind_*() routine returns. 2969** 2970** The sqlite3_bind_zeroblob() routine binds a BLOB of length N that 2971** is filled with zeroes. A zeroblob uses a fixed amount of memory 2972** (just an integer to hold its size) while it is being processed. 2973** Zeroblobs are intended to serve as placeholders for BLOBs whose 2974** content is later written using 2975** [sqlite3_blob_open | incremental BLOB I/O] routines. 2976** A negative value for the zeroblob results in a zero-length BLOB. 2977** 2978** The sqlite3_bind_*() routines must be called after 2979** [sqlite3_prepare_v2()] (and its variants) or [sqlite3_reset()] and 2980** before [sqlite3_step()]. 2981** Bindings are not cleared by the [sqlite3_reset()] routine. 2982** Unbound parameters are interpreted as NULL. 2983** 2984** These routines return [SQLITE_OK] on success or an error code if 2985** anything goes wrong. [SQLITE_RANGE] is returned if the parameter 2986** index is out of range. [SQLITE_NOMEM] is returned if malloc() fails. 2987** [SQLITE_MISUSE] might be returned if these routines are called on a 2988** virtual machine that is the wrong state or which has already been finalized. 2989** Detection of misuse is unreliable. Applications should not depend 2990** on SQLITE_MISUSE returns. SQLITE_MISUSE is intended to indicate a 2991** a logic error in the application. Future versions of SQLite might 2992** panic rather than return SQLITE_MISUSE. 2993** 2994** See also: [sqlite3_bind_parameter_count()], 2995** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. 2996** 2997** INVARIANTS: 2998** 2999** {H13506} The [SQL statement compiler] recognizes tokens of the forms 3000** "?", "?NNN", "$VVV", ":VVV", and "@VVV" as SQL parameters, 3001** where NNN is any sequence of one or more digits 3002** and where VVV is any sequence of one or more alphanumeric 3003** characters or "::" optionally followed by a string containing 3004** no spaces and contained within parentheses. 3005** 3006** {H13509} The initial value of an SQL parameter is NULL. 3007** 3008** {H13512} The index of an "?" SQL parameter is one larger than the 3009** largest index of SQL parameter to the left, or 1 if 3010** the "?" is the leftmost SQL parameter. 3011** 3012** {H13515} The index of an "?NNN" SQL parameter is the integer NNN. 3013** 3014** {H13518} The index of an ":VVV", "$VVV", or "@VVV" SQL parameter is 3015** the same as the index of leftmost occurrences of the same 3016** parameter, or one more than the largest index over all 3017** parameters to the left if this is the first occurrence 3018** of this parameter, or 1 if this is the leftmost parameter. 3019** 3020** {H13521} The [SQL statement compiler] fails with an [SQLITE_RANGE] 3021** error if the index of an SQL parameter is less than 1 3022** or greater than the compile-time SQLITE_MAX_VARIABLE_NUMBER 3023** parameter. 3024** 3025** {H13524} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,V,...)] 3026** associate the value V with all SQL parameters having an 3027** index of N in the [prepared statement] S. 3028** 3029** {H13527} Calls to [sqlite3_bind_text | sqlite3_bind(S,N,...)] 3030** override prior calls with the same values of S and N. 3031** 3032** {H13530} Bindings established by [sqlite3_bind_text | sqlite3_bind(S,...)] 3033** persist across calls to [sqlite3_reset(S)]. 3034** 3035** {H13533} In calls to [sqlite3_bind_blob(S,N,V,L,D)], 3036** [sqlite3_bind_text(S,N,V,L,D)], or 3037** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds the first L 3038** bytes of the BLOB or string pointed to by V, when L 3039** is non-negative. 3040** 3041** {H13536} In calls to [sqlite3_bind_text(S,N,V,L,D)] or 3042** [sqlite3_bind_text16(S,N,V,L,D)] SQLite binds characters 3043** from V through the first zero character when L is negative. 3044** 3045** {H13539} In calls to [sqlite3_bind_blob(S,N,V,L,D)], 3046** [sqlite3_bind_text(S,N,V,L,D)], or 3047** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special 3048** constant [SQLITE_STATIC], SQLite assumes that the value V 3049** is held in static unmanaged space that will not change 3050** during the lifetime of the binding. 3051** 3052** {H13542} In calls to [sqlite3_bind_blob(S,N,V,L,D)], 3053** [sqlite3_bind_text(S,N,V,L,D)], or 3054** [sqlite3_bind_text16(S,N,V,L,D)] when D is the special 3055** constant [SQLITE_TRANSIENT], the routine makes a 3056** private copy of the value V before it returns. 3057** 3058** {H13545} In calls to [sqlite3_bind_blob(S,N,V,L,D)], 3059** [sqlite3_bind_text(S,N,V,L,D)], or 3060** [sqlite3_bind_text16(S,N,V,L,D)] when D is a pointer to 3061** a function, SQLite invokes that function to destroy the 3062** value V after it has finished using the value V. 3063** 3064** {H13548} In calls to [sqlite3_bind_zeroblob(S,N,V,L)] the value bound 3065** is a BLOB of L bytes, or a zero-length BLOB if L is negative. 3066** 3067** {H13551} In calls to [sqlite3_bind_value(S,N,V)] the V argument may 3068** be either a [protected sqlite3_value] object or an 3069** [unprotected sqlite3_value] object. 3070*/ 3071int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); 3072int sqlite3_bind_double(sqlite3_stmt*, int, double); 3073int sqlite3_bind_int(sqlite3_stmt*, int, int); 3074int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); 3075int sqlite3_bind_null(sqlite3_stmt*, int); 3076int sqlite3_bind_text(sqlite3_stmt*, int, const char*, int n, void(*)(void*)); 3077int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); 3078int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); 3079int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); 3080 3081/* 3082** CAPI3REF: Number Of SQL Parameters {H13600} <S70300> 3083** 3084** This routine can be used to find the number of [SQL parameters] 3085** in a [prepared statement]. SQL parameters are tokens of the 3086** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as 3087** placeholders for values that are [sqlite3_bind_blob | bound] 3088** to the parameters at a later time. 3089** 3090** This routine actually returns the index of the largest (rightmost) 3091** parameter. For all forms except ?NNN, this will correspond to the 3092** number of unique parameters. If parameters of the ?NNN are used, 3093** there may be gaps in the list. 3094** 3095** See also: [sqlite3_bind_blob|sqlite3_bind()], 3096** [sqlite3_bind_parameter_name()], and 3097** [sqlite3_bind_parameter_index()]. 3098** 3099** INVARIANTS: 3100** 3101** {H13601} The [sqlite3_bind_parameter_count(S)] interface returns 3102** the largest index of all SQL parameters in the 3103** [prepared statement] S, or 0 if S contains no SQL parameters. 3104*/ 3105int sqlite3_bind_parameter_count(sqlite3_stmt*); 3106 3107/* 3108** CAPI3REF: Name Of A Host Parameter {H13620} <S70300> 3109** 3110** This routine returns a pointer to the name of the n-th 3111** [SQL parameter] in a [prepared statement]. 3112** SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" 3113** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" 3114** respectively. 3115** In other words, the initial ":" or "$" or "@" or "?" 3116** is included as part of the name. 3117** Parameters of the form "?" without a following integer have no name 3118** and are also referred to as "anonymous parameters". 3119** 3120** The first host parameter has an index of 1, not 0. 3121** 3122** If the value n is out of range or if the n-th parameter is 3123** nameless, then NULL is returned. The returned string is 3124** always in UTF-8 encoding even if the named parameter was 3125** originally specified as UTF-16 in [sqlite3_prepare16()] or 3126** [sqlite3_prepare16_v2()]. 3127** 3128** See also: [sqlite3_bind_blob|sqlite3_bind()], 3129** [sqlite3_bind_parameter_count()], and 3130** [sqlite3_bind_parameter_index()]. 3131** 3132** INVARIANTS: 3133** 3134** {H13621} The [sqlite3_bind_parameter_name(S,N)] interface returns 3135** a UTF-8 rendering of the name of the SQL parameter in 3136** the [prepared statement] S having index N, or 3137** NULL if there is no SQL parameter with index N or if the 3138** parameter with index N is an anonymous parameter "?". 3139*/ 3140const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); 3141 3142/* 3143** CAPI3REF: Index Of A Parameter With A Given Name {H13640} <S70300> 3144** 3145** Return the index of an SQL parameter given its name. The 3146** index value returned is suitable for use as the second 3147** parameter to [sqlite3_bind_blob|sqlite3_bind()]. A zero 3148** is returned if no matching parameter is found. The parameter 3149** name must be given in UTF-8 even if the original statement 3150** was prepared from UTF-16 text using [sqlite3_prepare16_v2()]. 3151** 3152** See also: [sqlite3_bind_blob|sqlite3_bind()], 3153** [sqlite3_bind_parameter_count()], and 3154** [sqlite3_bind_parameter_index()]. 3155** 3156** INVARIANTS: 3157** 3158** {H13641} The [sqlite3_bind_parameter_index(S,N)] interface returns 3159** the index of SQL parameter in the [prepared statement] 3160** S whose name matches the UTF-8 string N, or 0 if there is 3161** no match. 3162*/ 3163int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); 3164 3165/* 3166** CAPI3REF: Reset All Bindings On A Prepared Statement {H13660} <S70300> 3167** 3168** Contrary to the intuition of many, [sqlite3_reset()] does not reset 3169** the [sqlite3_bind_blob | bindings] on a [prepared statement]. 3170** Use this routine to reset all host parameters to NULL. 3171** 3172** INVARIANTS: 3173** 3174** {H13661} The [sqlite3_clear_bindings(S)] interface resets all SQL 3175** parameter bindings in the [prepared statement] S back to NULL. 3176*/ 3177int sqlite3_clear_bindings(sqlite3_stmt*); 3178 3179/* 3180** CAPI3REF: Number Of Columns In A Result Set {H13710} <S10700> 3181** 3182** Return the number of columns in the result set returned by the 3183** [prepared statement]. This routine returns 0 if pStmt is an SQL 3184** statement that does not return data (for example an [UPDATE]). 3185** 3186** INVARIANTS: 3187** 3188** {H13711} The [sqlite3_column_count(S)] interface returns the number of 3189** columns in the result set generated by the [prepared statement] S, 3190** or 0 if S does not generate a result set. 3191*/ 3192int sqlite3_column_count(sqlite3_stmt *pStmt); 3193 3194/* 3195** CAPI3REF: Column Names In A Result Set {H13720} <S10700> 3196** 3197** These routines return the name assigned to a particular column 3198** in the result set of a [SELECT] statement. The sqlite3_column_name() 3199** interface returns a pointer to a zero-terminated UTF-8 string 3200** and sqlite3_column_name16() returns a pointer to a zero-terminated 3201** UTF-16 string. The first parameter is the [prepared statement] 3202** that implements the [SELECT] statement. The second parameter is the 3203** column number. The leftmost column is number 0. 3204** 3205** The returned string pointer is valid until either the [prepared statement] 3206** is destroyed by [sqlite3_finalize()] or until the next call to 3207** sqlite3_column_name() or sqlite3_column_name16() on the same column. 3208** 3209** If sqlite3_malloc() fails during the processing of either routine 3210** (for example during a conversion from UTF-8 to UTF-16) then a 3211** NULL pointer is returned. 3212** 3213** The name of a result column is the value of the "AS" clause for 3214** that column, if there is an AS clause. If there is no AS clause 3215** then the name of the column is unspecified and may change from 3216** one release of SQLite to the next. 3217** 3218** INVARIANTS: 3219** 3220** {H13721} A successful invocation of the [sqlite3_column_name(S,N)] 3221** interface returns the name of the Nth column (where 0 is 3222** the leftmost column) for the result set of the 3223** [prepared statement] S as a zero-terminated UTF-8 string. 3224** 3225** {H13723} A successful invocation of the [sqlite3_column_name16(S,N)] 3226** interface returns the name of the Nth column (where 0 is 3227** the leftmost column) for the result set of the 3228** [prepared statement] S as a zero-terminated UTF-16 string 3229** in the native byte order. 3230** 3231** {H13724} The [sqlite3_column_name()] and [sqlite3_column_name16()] 3232** interfaces return a NULL pointer if they are unable to 3233** allocate memory to hold their normal return strings. 3234** 3235** {H13725} If the N parameter to [sqlite3_column_name(S,N)] or 3236** [sqlite3_column_name16(S,N)] is out of range, then the 3237** interfaces return a NULL pointer. 3238** 3239** {H13726} The strings returned by [sqlite3_column_name(S,N)] and 3240** [sqlite3_column_name16(S,N)] are valid until the next 3241** call to either routine with the same S and N parameters 3242** or until [sqlite3_finalize(S)] is called. 3243** 3244** {H13727} When a result column of a [SELECT] statement contains 3245** an AS clause, the name of that column is the identifier 3246** to the right of the AS keyword. 3247*/ 3248const char *sqlite3_column_name(sqlite3_stmt*, int N); 3249const void *sqlite3_column_name16(sqlite3_stmt*, int N); 3250 3251/* 3252** CAPI3REF: Source Of Data In A Query Result {H13740} <S10700> 3253** 3254** These routines provide a means to determine what column of what 3255** table in which database a result of a [SELECT] statement comes from. 3256** The name of the database or table or column can be returned as 3257** either a UTF-8 or UTF-16 string. The _database_ routines return 3258** the database name, the _table_ routines return the table name, and 3259** the origin_ routines return the column name. 3260** The returned string is valid until the [prepared statement] is destroyed 3261** using [sqlite3_finalize()] or until the same information is requested 3262** again in a different encoding. 3263** 3264** The names returned are the original un-aliased names of the 3265** database, table, and column. 3266** 3267** The first argument to the following calls is a [prepared statement]. 3268** These functions return information about the Nth column returned by 3269** the statement, where N is the second function argument. 3270** 3271** If the Nth column returned by the statement is an expression or 3272** subquery and is not a column value, then all of these functions return 3273** NULL. These routine might also return NULL if a memory allocation error 3274** occurs. Otherwise, they return the name of the attached database, table 3275** and column that query result column was extracted from. 3276** 3277** As with all other SQLite APIs, those postfixed with "16" return 3278** UTF-16 encoded strings, the other functions return UTF-8. {END} 3279** 3280** These APIs are only available if the library was compiled with the 3281** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined. 3282** 3283** {A13751} 3284** If two or more threads call one or more of these routines against the same 3285** prepared statement and column at the same time then the results are 3286** undefined. 3287** 3288** INVARIANTS: 3289** 3290** {H13741} The [sqlite3_column_database_name(S,N)] interface returns either 3291** the UTF-8 zero-terminated name of the database from which the 3292** Nth result column of the [prepared statement] S is extracted, 3293** or NULL if the Nth column of S is a general expression 3294** or if unable to allocate memory to store the name. 3295** 3296** {H13742} The [sqlite3_column_database_name16(S,N)] interface returns either 3297** the UTF-16 native byte order zero-terminated name of the database 3298** from which the Nth result column of the [prepared statement] S is 3299** extracted, or NULL if the Nth column of S is a general expression 3300** or if unable to allocate memory to store the name. 3301** 3302** {H13743} The [sqlite3_column_table_name(S,N)] interface returns either 3303** the UTF-8 zero-terminated name of the table from which the 3304** Nth result column of the [prepared statement] S is extracted, 3305** or NULL if the Nth column of S is a general expression 3306** or if unable to allocate memory to store the name. 3307** 3308** {H13744} The [sqlite3_column_table_name16(S,N)] interface returns either 3309** the UTF-16 native byte order zero-terminated name of the table 3310** from which the Nth result column of the [prepared statement] S is 3311** extracted, or NULL if the Nth column of S is a general expression 3312** or if unable to allocate memory to store the name. 3313** 3314** {H13745} The [sqlite3_column_origin_name(S,N)] interface returns either 3315** the UTF-8 zero-terminated name of the table column from which the 3316** Nth result column of the [prepared statement] S is extracted, 3317** or NULL if the Nth column of S is a general expression 3318** or if unable to allocate memory to store the name. 3319** 3320** {H13746} The [sqlite3_column_origin_name16(S,N)] interface returns either 3321** the UTF-16 native byte order zero-terminated name of the table 3322** column from which the Nth result column of the 3323** [prepared statement] S is extracted, or NULL if the Nth column 3324** of S is a general expression or if unable to allocate memory 3325** to store the name. 3326** 3327** {H13748} The return values from 3328** [sqlite3_column_database_name | column metadata interfaces] 3329** are valid for the lifetime of the [prepared statement] 3330** or until the encoding is changed by another metadata 3331** interface call for the same prepared statement and column. 3332** 3333** ASSUMPTIONS: 3334** 3335** {A13751} If two or more threads call one or more 3336** [sqlite3_column_database_name | column metadata interfaces] 3337** for the same [prepared statement] and result column 3338** at the same time then the results are undefined. 3339*/ 3340const char *sqlite3_column_database_name(sqlite3_stmt*,int); 3341const void *sqlite3_column_database_name16(sqlite3_stmt*,int); 3342const char *sqlite3_column_table_name(sqlite3_stmt*,int); 3343const void *sqlite3_column_table_name16(sqlite3_stmt*,int); 3344const char *sqlite3_column_origin_name(sqlite3_stmt*,int); 3345const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); 3346 3347/* 3348** CAPI3REF: Declared Datatype Of A Query Result {H13760} <S10700> 3349** 3350** The first parameter is a [prepared statement]. 3351** If this statement is a [SELECT] statement and the Nth column of the 3352** returned result set of that [SELECT] is a table column (not an 3353** expression or subquery) then the declared type of the table 3354** column is returned. If the Nth column of the result set is an 3355** expression or subquery, then a NULL pointer is returned. 3356** The returned string is always UTF-8 encoded. {END} 3357** 3358** For example, given the database schema: 3359** 3360** CREATE TABLE t1(c1 VARIANT); 3361** 3362** and the following statement to be compiled: 3363** 3364** SELECT c1 + 1, c1 FROM t1; 3365** 3366** this routine would return the string "VARIANT" for the second result 3367** column (i==1), and a NULL pointer for the first result column (i==0). 3368** 3369** SQLite uses dynamic run-time typing. So just because a column 3370** is declared to contain a particular type does not mean that the 3371** data stored in that column is of the declared type. SQLite is 3372** strongly typed, but the typing is dynamic not static. Type 3373** is associated with individual values, not with the containers 3374** used to hold those values. 3375** 3376** INVARIANTS: 3377** 3378** {H13761} A successful call to [sqlite3_column_decltype(S,N)] returns a 3379** zero-terminated UTF-8 string containing the declared datatype 3380** of the table column that appears as the Nth column (numbered 3381** from 0) of the result set to the [prepared statement] S. 3382** 3383** {H13762} A successful call to [sqlite3_column_decltype16(S,N)] 3384** returns a zero-terminated UTF-16 native byte order string 3385** containing the declared datatype of the table column that appears 3386** as the Nth column (numbered from 0) of the result set to the 3387** [prepared statement] S. 3388** 3389** {H13763} If N is less than 0 or N is greater than or equal to 3390** the number of columns in the [prepared statement] S, 3391** or if the Nth column of S is an expression or subquery rather 3392** than a table column, or if a memory allocation failure 3393** occurs during encoding conversions, then 3394** calls to [sqlite3_column_decltype(S,N)] or 3395** [sqlite3_column_decltype16(S,N)] return NULL. 3396*/ 3397const char *sqlite3_column_decltype(sqlite3_stmt*,int); 3398const void *sqlite3_column_decltype16(sqlite3_stmt*,int); 3399 3400/* 3401** CAPI3REF: Evaluate An SQL Statement {H13200} <S10000> 3402** 3403** After a [prepared statement] has been prepared using either 3404** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy 3405** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function 3406** must be called one or more times to evaluate the statement. 3407** 3408** The details of the behavior of the sqlite3_step() interface depend 3409** on whether the statement was prepared using the newer "v2" interface 3410** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy 3411** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the 3412** new "v2" interface is recommended for new applications but the legacy 3413** interface will continue to be supported. 3414** 3415** In the legacy interface, the return value will be either [SQLITE_BUSY], 3416** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. 3417** With the "v2" interface, any of the other [result codes] or 3418** [extended result codes] might be returned as well. 3419** 3420** [SQLITE_BUSY] means that the database engine was unable to acquire the 3421** database locks it needs to do its job. If the statement is a [COMMIT] 3422** or occurs outside of an explicit transaction, then you can retry the 3423** statement. If the statement is not a [COMMIT] and occurs within a 3424** explicit transaction then you should rollback the transaction before 3425** continuing. 3426** 3427** [SQLITE_DONE] means that the statement has finished executing 3428** successfully. sqlite3_step() should not be called again on this virtual 3429** machine without first calling [sqlite3_reset()] to reset the virtual 3430** machine back to its initial state. 3431** 3432** If the SQL statement being executed returns any data, then [SQLITE_ROW] 3433** is returned each time a new row of data is ready for processing by the 3434** caller. The values may be accessed using the [column access functions]. 3435** sqlite3_step() is called again to retrieve the next row of data. 3436** 3437** [SQLITE_ERROR] means that a run-time error (such as a constraint 3438** violation) has occurred. sqlite3_step() should not be called again on 3439** the VM. More information may be found by calling [sqlite3_errmsg()]. 3440** With the legacy interface, a more specific error code (for example, 3441** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) 3442** can be obtained by calling [sqlite3_reset()] on the 3443** [prepared statement]. In the "v2" interface, 3444** the more specific error code is returned directly by sqlite3_step(). 3445** 3446** [SQLITE_MISUSE] means that the this routine was called inappropriately. 3447** Perhaps it was called on a [prepared statement] that has 3448** already been [sqlite3_finalize | finalized] or on one that had 3449** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could 3450** be the case that the same database connection is being used by two or 3451** more threads at the same moment in time. 3452** 3453** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() 3454** API always returns a generic error code, [SQLITE_ERROR], following any 3455** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call 3456** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the 3457** specific [error codes] that better describes the error. 3458** We admit that this is a goofy design. The problem has been fixed 3459** with the "v2" interface. If you prepare all of your SQL statements 3460** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead 3461** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, 3462** then the more specific [error codes] are returned directly 3463** by sqlite3_step(). The use of the "v2" interface is recommended. 3464** 3465** INVARIANTS: 3466** 3467** {H13202} If the [prepared statement] S is ready to be run, then 3468** [sqlite3_step(S)] advances that prepared statement until 3469** completion or until it is ready to return another row of the 3470** result set, or until an [sqlite3_interrupt | interrupt] 3471** or a run-time error occurs. 3472** 3473** {H15304} When a call to [sqlite3_step(S)] causes the [prepared statement] 3474** S to run to completion, the function returns [SQLITE_DONE]. 3475** 3476** {H15306} When a call to [sqlite3_step(S)] stops because it is ready to 3477** return another row of the result set, it returns [SQLITE_ROW]. 3478** 3479** {H15308} If a call to [sqlite3_step(S)] encounters an 3480** [sqlite3_interrupt | interrupt] or a run-time error, 3481** it returns an appropriate error code that is not one of 3482** [SQLITE_OK], [SQLITE_ROW], or [SQLITE_DONE]. 3483** 3484** {H15310} If an [sqlite3_interrupt | interrupt] or a run-time error 3485** occurs during a call to [sqlite3_step(S)] 3486** for a [prepared statement] S created using 3487** legacy interfaces [sqlite3_prepare()] or 3488** [sqlite3_prepare16()], then the function returns either 3489** [SQLITE_ERROR], [SQLITE_BUSY], or [SQLITE_MISUSE]. 3490*/ 3491int sqlite3_step(sqlite3_stmt*); 3492 3493/* 3494** CAPI3REF: Number of columns in a result set {H13770} <S10700> 3495** 3496** Returns the number of values in the current row of the result set. 3497** 3498** INVARIANTS: 3499** 3500** {H13771} After a call to [sqlite3_step(S)] that returns [SQLITE_ROW], 3501** the [sqlite3_data_count(S)] routine will return the same value 3502** as the [sqlite3_column_count(S)] function. 3503** 3504** {H13772} After [sqlite3_step(S)] has returned any value other than 3505** [SQLITE_ROW] or before [sqlite3_step(S)] has been called on the 3506** [prepared statement] for the first time since it was 3507** [sqlite3_prepare | prepared] or [sqlite3_reset | reset], 3508** the [sqlite3_data_count(S)] routine returns zero. 3509*/ 3510int sqlite3_data_count(sqlite3_stmt *pStmt); 3511 3512/* 3513** CAPI3REF: Fundamental Datatypes {H10265} <S10110><S10120> 3514** KEYWORDS: SQLITE_TEXT 3515** 3516** {H10266} Every value in SQLite has one of five fundamental datatypes: 3517** 3518** <ul> 3519** <li> 64-bit signed integer 3520** <li> 64-bit IEEE floating point number 3521** <li> string 3522** <li> BLOB 3523** <li> NULL 3524** </ul> {END} 3525** 3526** These constants are codes for each of those types. 3527** 3528** Note that the SQLITE_TEXT constant was also used in SQLite version 2 3529** for a completely different meaning. Software that links against both 3530** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not 3531** SQLITE_TEXT. 3532*/ 3533#define SQLITE_INTEGER 1 3534#define SQLITE_FLOAT 2 3535#define SQLITE_BLOB 4 3536#define SQLITE_NULL 5 3537#ifdef SQLITE_TEXT 3538# undef SQLITE_TEXT 3539#else 3540# define SQLITE_TEXT 3 3541#endif 3542#define SQLITE3_TEXT 3 3543 3544/* 3545** CAPI3REF: Result Values From A Query {H13800} <S10700> 3546** KEYWORDS: {column access functions} 3547** 3548** These routines form the "result set query" interface. 3549** 3550** These routines return information about a single column of the current 3551** result row of a query. In every case the first argument is a pointer 3552** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] 3553** that was returned from [sqlite3_prepare_v2()] or one of its variants) 3554** and the second argument is the index of the column for which information 3555** should be returned. The leftmost column of the result set has the index 0. 3556** 3557** If the SQL statement does not currently point to a valid row, or if the 3558** column index is out of range, the result is undefined. 3559** These routines may only be called when the most recent call to 3560** [sqlite3_step()] has returned [SQLITE_ROW] and neither 3561** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. 3562** If any of these routines are called after [sqlite3_reset()] or 3563** [sqlite3_finalize()] or after [sqlite3_step()] has returned 3564** something other than [SQLITE_ROW], the results are undefined. 3565** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] 3566** are called from a different thread while any of these routines 3567** are pending, then the results are undefined. 3568** 3569** The sqlite3_column_type() routine returns the 3570** [SQLITE_INTEGER | datatype code] for the initial data type 3571** of the result column. The returned value is one of [SQLITE_INTEGER], 3572** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value 3573** returned by sqlite3_column_type() is only meaningful if no type 3574** conversions have occurred as described below. After a type conversion, 3575** the value returned by sqlite3_column_type() is undefined. Future 3576** versions of SQLite may change the behavior of sqlite3_column_type() 3577** following a type conversion. 3578** 3579** If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 3580** routine returns the number of bytes in that BLOB or string. 3581** If the result is a UTF-16 string, then sqlite3_column_bytes() converts 3582** the string to UTF-8 and then returns the number of bytes. 3583** If the result is a numeric value then sqlite3_column_bytes() uses 3584** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns 3585** the number of bytes in that string. 3586** The value returned does not include the zero terminator at the end 3587** of the string. For clarity: the value returned is the number of 3588** bytes in the string, not the number of characters. 3589** 3590** Strings returned by sqlite3_column_text() and sqlite3_column_text16(), 3591** even empty strings, are always zero terminated. The return 3592** value from sqlite3_column_blob() for a zero-length BLOB is an arbitrary 3593** pointer, possibly even a NULL pointer. 3594** 3595** The sqlite3_column_bytes16() routine is similar to sqlite3_column_bytes() 3596** but leaves the result in UTF-16 in native byte order instead of UTF-8. 3597** The zero terminator is not included in this count. 3598** 3599** The object returned by [sqlite3_column_value()] is an 3600** [unprotected sqlite3_value] object. An unprotected sqlite3_value object 3601** may only be used with [sqlite3_bind_value()] and [sqlite3_result_value()]. 3602** If the [unprotected sqlite3_value] object returned by 3603** [sqlite3_column_value()] is used in any other way, including calls 3604** to routines like [sqlite3_value_int()], [sqlite3_value_text()], 3605** or [sqlite3_value_bytes()], then the behavior is undefined. 3606** 3607** These routines attempt to convert the value where appropriate. For 3608** example, if the internal representation is FLOAT and a text result 3609** is requested, [sqlite3_snprintf()] is used internally to perform the 3610** conversion automatically. The following table details the conversions 3611** that are applied: 3612** 3613** <blockquote> 3614** <table border="1"> 3615** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion 3616** 3617** <tr><td> NULL <td> INTEGER <td> Result is 0 3618** <tr><td> NULL <td> FLOAT <td> Result is 0.0 3619** <tr><td> NULL <td> TEXT <td> Result is NULL pointer 3620** <tr><td> NULL <td> BLOB <td> Result is NULL pointer 3621** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float 3622** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer 3623** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT 3624** <tr><td> FLOAT <td> INTEGER <td> Convert from float to integer 3625** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float 3626** <tr><td> FLOAT <td> BLOB <td> Same as FLOAT->TEXT 3627** <tr><td> TEXT <td> INTEGER <td> Use atoi() 3628** <tr><td> TEXT <td> FLOAT <td> Use atof() 3629** <tr><td> TEXT <td> BLOB <td> No change 3630** <tr><td> BLOB <td> INTEGER <td> Convert to TEXT then use atoi() 3631** <tr><td> BLOB <td> FLOAT <td> Convert to TEXT then use atof() 3632** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed 3633** </table> 3634** </blockquote> 3635** 3636** The table above makes reference to standard C library functions atoi() 3637** and atof(). SQLite does not really use these functions. It has its 3638** own equivalent internal routines. The atoi() and atof() names are 3639** used in the table for brevity and because they are familiar to most 3640** C programmers. 3641** 3642** Note that when type conversions occur, pointers returned by prior 3643** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or 3644** sqlite3_column_text16() may be invalidated. 3645** Type conversions and pointer invalidations might occur 3646** in the following cases: 3647** 3648** <ul> 3649** <li> The initial content is a BLOB and sqlite3_column_text() or 3650** sqlite3_column_text16() is called. A zero-terminator might 3651** need to be added to the string.</li> 3652** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or 3653** sqlite3_column_text16() is called. The content must be converted 3654** to UTF-16.</li> 3655** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or 3656** sqlite3_column_text() is called. The content must be converted 3657** to UTF-8.</li> 3658** </ul> 3659** 3660** Conversions between UTF-16be and UTF-16le are always done in place and do 3661** not invalidate a prior pointer, though of course the content of the buffer 3662** that the prior pointer points to will have been modified. Other kinds 3663** of conversion are done in place when it is possible, but sometimes they 3664** are not possible and in those cases prior pointers are invalidated. 3665** 3666** The safest and easiest to remember policy is to invoke these routines 3667** in one of the following ways: 3668** 3669** <ul> 3670** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> 3671** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> 3672** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> 3673** </ul> 3674** 3675** In other words, you should call sqlite3_column_text(), 3676** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result 3677** into the desired format, then invoke sqlite3_column_bytes() or 3678** sqlite3_column_bytes16() to find the size of the result. Do not mix calls 3679** to sqlite3_column_text() or sqlite3_column_blob() with calls to 3680** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() 3681** with calls to sqlite3_column_bytes(). 3682** 3683** The pointers returned are valid until a type conversion occurs as 3684** described above, or until [sqlite3_step()] or [sqlite3_reset()] or 3685** [sqlite3_finalize()] is called. The memory space used to hold strings 3686** and BLOBs is freed automatically. Do <b>not</b> pass the pointers returned 3687** [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 3688** [sqlite3_free()]. 3689** 3690** If a memory allocation error occurs during the evaluation of any 3691** of these routines, a default value is returned. The default value 3692** is either the integer 0, the floating point number 0.0, or a NULL 3693** pointer. Subsequent calls to [sqlite3_errcode()] will return 3694** [SQLITE_NOMEM]. 3695** 3696** INVARIANTS: 3697** 3698** {H13803} The [sqlite3_column_blob(S,N)] interface converts the 3699** Nth column in the current row of the result set for 3700** the [prepared statement] S into a BLOB and then returns a 3701** pointer to the converted value. 3702** 3703** {H13806} The [sqlite3_column_bytes(S,N)] interface returns the 3704** number of bytes in the BLOB or string (exclusive of the 3705** zero terminator on the string) that was returned by the 3706** most recent call to [sqlite3_column_blob(S,N)] or 3707** [sqlite3_column_text(S,N)]. 3708** 3709** {H13809} The [sqlite3_column_bytes16(S,N)] interface returns the 3710** number of bytes in the string (exclusive of the 3711** zero terminator on the string) that was returned by the 3712** most recent call to [sqlite3_column_text16(S,N)]. 3713** 3714** {H13812} The [sqlite3_column_double(S,N)] interface converts the 3715** Nth column in the current row of the result set for the 3716** [prepared statement] S into a floating point value and 3717** returns a copy of that value. 3718** 3719** {H13815} The [sqlite3_column_int(S,N)] interface converts the 3720** Nth column in the current row of the result set for the 3721** [prepared statement] S into a 64-bit signed integer and 3722** returns the lower 32 bits of that integer. 3723** 3724** {H13818} The [sqlite3_column_int64(S,N)] interface converts the 3725** Nth column in the current row of the result set for the 3726** [prepared statement] S into a 64-bit signed integer and 3727** returns a copy of that integer. 3728** 3729** {H13821} The [sqlite3_column_text(S,N)] interface converts the 3730** Nth column in the current row of the result set for 3731** the [prepared statement] S into a zero-terminated UTF-8 3732** string and returns a pointer to that string. 3733** 3734** {H13824} The [sqlite3_column_text16(S,N)] interface converts the 3735** Nth column in the current row of the result set for the 3736** [prepared statement] S into a zero-terminated 2-byte 3737** aligned UTF-16 native byte order string and returns 3738** a pointer to that string. 3739** 3740** {H13827} The [sqlite3_column_type(S,N)] interface returns 3741** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT], 3742** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for 3743** the Nth column in the current row of the result set for 3744** the [prepared statement] S. 3745** 3746** {H13830} The [sqlite3_column_value(S,N)] interface returns a 3747** pointer to an [unprotected sqlite3_value] object for the 3748** Nth column in the current row of the result set for 3749** the [prepared statement] S. 3750*/ 3751const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); 3752int sqlite3_column_bytes(sqlite3_stmt*, int iCol); 3753int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); 3754double sqlite3_column_double(sqlite3_stmt*, int iCol); 3755int sqlite3_column_int(sqlite3_stmt*, int iCol); 3756sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); 3757const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); 3758const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); 3759int sqlite3_column_type(sqlite3_stmt*, int iCol); 3760sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); 3761 3762/* 3763** CAPI3REF: Destroy A Prepared Statement Object {H13300} <S70300><S30100> 3764** 3765** The sqlite3_finalize() function is called to delete a [prepared statement]. 3766** If the statement was executed successfully or not executed at all, then 3767** SQLITE_OK is returned. If execution of the statement failed then an 3768** [error code] or [extended error code] is returned. 3769** 3770** This routine can be called at any point during the execution of the 3771** [prepared statement]. If the virtual machine has not 3772** completed execution when this routine is called, that is like 3773** encountering an error or an [sqlite3_interrupt | interrupt]. 3774** Incomplete updates may be rolled back and transactions canceled, 3775** depending on the circumstances, and the 3776** [error code] returned will be [SQLITE_ABORT]. 3777** 3778** INVARIANTS: 3779** 3780** {H11302} The [sqlite3_finalize(S)] interface destroys the 3781** [prepared statement] S and releases all 3782** memory and file resources held by that object. 3783** 3784** {H11304} If the most recent call to [sqlite3_step(S)] for the 3785** [prepared statement] S returned an error, 3786** then [sqlite3_finalize(S)] returns that same error. 3787*/ 3788int sqlite3_finalize(sqlite3_stmt *pStmt); 3789 3790/* 3791** CAPI3REF: Reset A Prepared Statement Object {H13330} <S70300> 3792** 3793** The sqlite3_reset() function is called to reset a [prepared statement] 3794** object back to its initial state, ready to be re-executed. 3795** Any SQL statement variables that had values bound to them using 3796** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. 3797** Use [sqlite3_clear_bindings()] to reset the bindings. 3798** 3799** {H11332} The [sqlite3_reset(S)] interface resets the [prepared statement] S 3800** back to the beginning of its program. 3801** 3802** {H11334} If the most recent call to [sqlite3_step(S)] for the 3803** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], 3804** or if [sqlite3_step(S)] has never before been called on S, 3805** then [sqlite3_reset(S)] returns [SQLITE_OK]. 3806** 3807** {H11336} If the most recent call to [sqlite3_step(S)] for the 3808** [prepared statement] S indicated an error, then 3809** [sqlite3_reset(S)] returns an appropriate [error code]. 3810** 3811** {H11338} The [sqlite3_reset(S)] interface does not change the values 3812** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. 3813*/ 3814int sqlite3_reset(sqlite3_stmt *pStmt); 3815 3816/* 3817** CAPI3REF: Create Or Redefine SQL Functions {H16100} <S20200> 3818** KEYWORDS: {function creation routines} 3819** KEYWORDS: {application-defined SQL function} 3820** KEYWORDS: {application-defined SQL functions} 3821** 3822** These two functions (collectively known as "function creation routines") 3823** are used to add SQL functions or aggregates or to redefine the behavior 3824** of existing SQL functions or aggregates. The only difference between the 3825** two is that the second parameter, the name of the (scalar) function or 3826** aggregate, is encoded in UTF-8 for sqlite3_create_function() and UTF-16 3827** for sqlite3_create_function16(). 3828** 3829** The first parameter is the [database connection] to which the SQL 3830** function is to be added. If a single program uses more than one database 3831** connection internally, then SQL functions must be added individually to 3832** each database connection. 3833** 3834** The second parameter is the name of the SQL function to be created or 3835** redefined. The length of the name is limited to 255 bytes, exclusive of 3836** the zero-terminator. Note that the name length limit is in bytes, not 3837** characters. Any attempt to create a function with a longer name 3838** will result in [SQLITE_ERROR] being returned. 3839** 3840** The third parameter is the number of arguments that the SQL function or 3841** aggregate takes. If this parameter is negative, then the SQL function or 3842** aggregate may take any number of arguments. 3843** 3844** The fourth parameter, eTextRep, specifies what 3845** [SQLITE_UTF8 | text encoding] this SQL function prefers for 3846** its parameters. Any SQL function implementation should be able to work 3847** work with UTF-8, UTF-16le, or UTF-16be. But some implementations may be 3848** more efficient with one encoding than another. It is allowed to 3849** invoke sqlite3_create_function() or sqlite3_create_function16() multiple 3850** times with the same function but with different values of eTextRep. 3851** When multiple implementations of the same function are available, SQLite 3852** will pick the one that involves the least amount of data conversion. 3853** If there is only a single implementation which does not care what text 3854** encoding is used, then the fourth argument should be [SQLITE_ANY]. 3855** 3856** The fifth parameter is an arbitrary pointer. The implementation of the 3857** function can gain access to this pointer using [sqlite3_user_data()]. 3858** 3859** The seventh, eighth and ninth parameters, xFunc, xStep and xFinal, are 3860** pointers to C-language functions that implement the SQL function or 3861** aggregate. A scalar SQL function requires an implementation of the xFunc 3862** callback only, NULL pointers should be passed as the xStep and xFinal 3863** parameters. An aggregate SQL function requires an implementation of xStep 3864** and xFinal and NULL should be passed for xFunc. To delete an existing 3865** SQL function or aggregate, pass NULL for all three function callbacks. 3866** 3867** It is permitted to register multiple implementations of the same 3868** functions with the same name but with either differing numbers of 3869** arguments or differing preferred text encodings. SQLite will use 3870** the implementation most closely matches the way in which the 3871** SQL function is used. 3872** 3873** INVARIANTS: 3874** 3875** {H16103} The [sqlite3_create_function16()] interface behaves exactly 3876** like [sqlite3_create_function()] in every way except that it 3877** interprets the zFunctionName argument as zero-terminated UTF-16 3878** native byte order instead of as zero-terminated UTF-8. 3879** 3880** {H16106} A successful invocation of 3881** the [sqlite3_create_function(D,X,N,E,...)] interface registers 3882** or replaces callback functions in the [database connection] D 3883** used to implement the SQL function named X with N parameters 3884** and having a preferred text encoding of E. 3885** 3886** {H16109} A successful call to [sqlite3_create_function(D,X,N,E,P,F,S,L)] 3887** replaces the P, F, S, and L values from any prior calls with 3888** the same D, X, N, and E values. 3889** 3890** {H16112} The [sqlite3_create_function(D,X,...)] interface fails with 3891** a return code of [SQLITE_ERROR] if the SQL function name X is 3892** longer than 255 bytes exclusive of the zero terminator. 3893** 3894** {H16118} Either F must be NULL and S and L are non-NULL or else F 3895** is non-NULL and S and L are NULL, otherwise 3896** [sqlite3_create_function(D,X,N,E,P,F,S,L)] returns [SQLITE_ERROR]. 3897** 3898** {H16121} The [sqlite3_create_function(D,...)] interface fails with an 3899** error code of [SQLITE_BUSY] if there exist [prepared statements] 3900** associated with the [database connection] D. 3901** 3902** {H16124} The [sqlite3_create_function(D,X,N,...)] interface fails with an 3903** error code of [SQLITE_ERROR] if parameter N (specifying the number 3904** of arguments to the SQL function being registered) is less 3905** than -1 or greater than 127. 3906** 3907** {H16127} When N is non-negative, the [sqlite3_create_function(D,X,N,...)] 3908** interface causes callbacks to be invoked for the SQL function 3909** named X when the number of arguments to the SQL function is 3910** exactly N. 3911** 3912** {H16130} When N is -1, the [sqlite3_create_function(D,X,N,...)] 3913** interface causes callbacks to be invoked for the SQL function 3914** named X with any number of arguments. 3915** 3916** {H16133} When calls to [sqlite3_create_function(D,X,N,...)] 3917** specify multiple implementations of the same function X 3918** and when one implementation has N>=0 and the other has N=(-1) 3919** the implementation with a non-zero N is preferred. 3920** 3921** {H16136} When calls to [sqlite3_create_function(D,X,N,E,...)] 3922** specify multiple implementations of the same function X with 3923** the same number of arguments N but with different 3924** encodings E, then the implementation where E matches the 3925** database encoding is preferred. 3926** 3927** {H16139} For an aggregate SQL function created using 3928** [sqlite3_create_function(D,X,N,E,P,0,S,L)] the finalizer 3929** function L will always be invoked exactly once if the 3930** step function S is called one or more times. 3931** 3932** {H16142} When SQLite invokes either the xFunc or xStep function of 3933** an application-defined SQL function or aggregate created 3934** by [sqlite3_create_function()] or [sqlite3_create_function16()], 3935** then the array of [sqlite3_value] objects passed as the 3936** third parameter are always [protected sqlite3_value] objects. 3937*/ 3938int sqlite3_create_function( 3939 sqlite3 *db, 3940 const char *zFunctionName, 3941 int nArg, 3942 int eTextRep, 3943 void *pApp, 3944 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 3945 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 3946 void (*xFinal)(sqlite3_context*) 3947); 3948int sqlite3_create_function16( 3949 sqlite3 *db, 3950 const void *zFunctionName, 3951 int nArg, 3952 int eTextRep, 3953 void *pApp, 3954 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 3955 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 3956 void (*xFinal)(sqlite3_context*) 3957); 3958 3959/* 3960** CAPI3REF: Text Encodings {H10267} <S50200> <H16100> 3961** 3962** These constant define integer codes that represent the various 3963** text encodings supported by SQLite. 3964*/ 3965#define SQLITE_UTF8 1 3966#define SQLITE_UTF16LE 2 3967#define SQLITE_UTF16BE 3 3968#define SQLITE_UTF16 4 /* Use native byte order */ 3969#define SQLITE_ANY 5 /* sqlite3_create_function only */ 3970#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ 3971 3972/* 3973** CAPI3REF: Deprecated Functions 3974** DEPRECATED 3975** 3976** These functions are [deprecated]. In order to maintain 3977** backwards compatibility with older code, these functions continue 3978** to be supported. However, new applications should avoid 3979** the use of these functions. To help encourage people to avoid 3980** using these functions, we are not going to tell you want they do. 3981*/ 3982SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); 3983SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); 3984SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); 3985SQLITE_DEPRECATED int sqlite3_global_recover(void); 3986SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); 3987SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64); 3988 3989/* 3990** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200> 3991** 3992** The C-language implementation of SQL functions and aggregates uses 3993** this set of interface routines to access the parameter values on 3994** the function or aggregate. 3995** 3996** The xFunc (for scalar functions) or xStep (for aggregates) parameters 3997** to [sqlite3_create_function()] and [sqlite3_create_function16()] 3998** define callbacks that implement the SQL functions and aggregates. 3999** The 4th parameter to these callbacks is an array of pointers to 4000** [protected sqlite3_value] objects. There is one [sqlite3_value] object for 4001** each parameter to the SQL function. These routines are used to 4002** extract values from the [sqlite3_value] objects. 4003** 4004** These routines work only with [protected sqlite3_value] objects. 4005** Any attempt to use these routines on an [unprotected sqlite3_value] 4006** object results in undefined behavior. 4007** 4008** These routines work just like the corresponding [column access functions] 4009** except that these routines take a single [protected sqlite3_value] object 4010** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. 4011** 4012** The sqlite3_value_text16() interface extracts a UTF-16 string 4013** in the native byte-order of the host machine. The 4014** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces 4015** extract UTF-16 strings as big-endian and little-endian respectively. 4016** 4017** The sqlite3_value_numeric_type() interface attempts to apply 4018** numeric affinity to the value. This means that an attempt is 4019** made to convert the value to an integer or floating point. If 4020** such a conversion is possible without loss of information (in other 4021** words, if the value is a string that looks like a number) 4022** then the conversion is performed. Otherwise no conversion occurs. 4023** The [SQLITE_INTEGER | datatype] after conversion is returned. 4024** 4025** Please pay particular attention to the fact that the pointer returned 4026** from [sqlite3_value_blob()], [sqlite3_value_text()], or 4027** [sqlite3_value_text16()] can be invalidated by a subsequent call to 4028** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], 4029** or [sqlite3_value_text16()]. 4030** 4031** These routines must be called from the same thread as 4032** the SQL function that supplied the [sqlite3_value*] parameters. 4033** 4034** INVARIANTS: 4035** 4036** {H15103} The [sqlite3_value_blob(V)] interface converts the 4037** [protected sqlite3_value] object V into a BLOB and then 4038** returns a pointer to the converted value. 4039** 4040** {H15106} The [sqlite3_value_bytes(V)] interface returns the 4041** number of bytes in the BLOB or string (exclusive of the 4042** zero terminator on the string) that was returned by the 4043** most recent call to [sqlite3_value_blob(V)] or 4044** [sqlite3_value_text(V)]. 4045** 4046** {H15109} The [sqlite3_value_bytes16(V)] interface returns the 4047** number of bytes in the string (exclusive of the 4048** zero terminator on the string) that was returned by the 4049** most recent call to [sqlite3_value_text16(V)], 4050** [sqlite3_value_text16be(V)], or [sqlite3_value_text16le(V)]. 4051** 4052** {H15112} The [sqlite3_value_double(V)] interface converts the 4053** [protected sqlite3_value] object V into a floating point value and 4054** returns a copy of that value. 4055** 4056** {H15115} The [sqlite3_value_int(V)] interface converts the 4057** [protected sqlite3_value] object V into a 64-bit signed integer and 4058** returns the lower 32 bits of that integer. 4059** 4060** {H15118} The [sqlite3_value_int64(V)] interface converts the 4061** [protected sqlite3_value] object V into a 64-bit signed integer and 4062** returns a copy of that integer. 4063** 4064** {H15121} The [sqlite3_value_text(V)] interface converts the 4065** [protected sqlite3_value] object V into a zero-terminated UTF-8 4066** string and returns a pointer to that string. 4067** 4068** {H15124} The [sqlite3_value_text16(V)] interface converts the 4069** [protected sqlite3_value] object V into a zero-terminated 2-byte 4070** aligned UTF-16 native byte order 4071** string and returns a pointer to that string. 4072** 4073** {H15127} The [sqlite3_value_text16be(V)] interface converts the 4074** [protected sqlite3_value] object V into a zero-terminated 2-byte 4075** aligned UTF-16 big-endian 4076** string and returns a pointer to that string. 4077** 4078** {H15130} The [sqlite3_value_text16le(V)] interface converts the 4079** [protected sqlite3_value] object V into a zero-terminated 2-byte 4080** aligned UTF-16 little-endian 4081** string and returns a pointer to that string. 4082** 4083** {H15133} The [sqlite3_value_type(V)] interface returns 4084** one of [SQLITE_NULL], [SQLITE_INTEGER], [SQLITE_FLOAT], 4085** [SQLITE_TEXT], or [SQLITE_BLOB] as appropriate for 4086** the [sqlite3_value] object V. 4087** 4088** {H15136} The [sqlite3_value_numeric_type(V)] interface converts 4089** the [protected sqlite3_value] object V into either an integer or 4090** a floating point value if it can do so without loss of 4091** information, and returns one of [SQLITE_NULL], 4092** [SQLITE_INTEGER], [SQLITE_FLOAT], [SQLITE_TEXT], or 4093** [SQLITE_BLOB] as appropriate for the 4094** [protected sqlite3_value] object V after the conversion attempt. 4095*/ 4096const void *sqlite3_value_blob(sqlite3_value*); 4097int sqlite3_value_bytes(sqlite3_value*); 4098int sqlite3_value_bytes16(sqlite3_value*); 4099double sqlite3_value_double(sqlite3_value*); 4100int sqlite3_value_int(sqlite3_value*); 4101sqlite3_int64 sqlite3_value_int64(sqlite3_value*); 4102const unsigned char *sqlite3_value_text(sqlite3_value*); 4103const void *sqlite3_value_text16(sqlite3_value*); 4104const void *sqlite3_value_text16le(sqlite3_value*); 4105const void *sqlite3_value_text16be(sqlite3_value*); 4106int sqlite3_value_type(sqlite3_value*); 4107int sqlite3_value_numeric_type(sqlite3_value*); 4108 4109/* 4110** CAPI3REF: Obtain Aggregate Function Context {H16210} <S20200> 4111** 4112** The implementation of aggregate SQL functions use this routine to allocate 4113** a structure for storing their state. 4114** 4115** The first time the sqlite3_aggregate_context() routine is called for a 4116** particular aggregate, SQLite allocates nBytes of memory, zeroes out that 4117** memory, and returns a pointer to it. On second and subsequent calls to 4118** sqlite3_aggregate_context() for the same aggregate function index, 4119** the same buffer is returned. The implementation of the aggregate can use 4120** the returned buffer to accumulate data. 4121** 4122** SQLite automatically frees the allocated buffer when the aggregate 4123** query concludes. 4124** 4125** The first parameter should be a copy of the 4126** [sqlite3_context | SQL function context] that is the first parameter 4127** to the callback routine that implements the aggregate function. 4128** 4129** This routine must be called from the same thread in which 4130** the aggregate SQL function is running. 4131** 4132** INVARIANTS: 4133** 4134** {H16211} The first invocation of [sqlite3_aggregate_context(C,N)] for 4135** a particular instance of an aggregate function (for a particular 4136** context C) causes SQLite to allocate N bytes of memory, 4137** zero that memory, and return a pointer to the allocated memory. 4138** 4139** {H16213} If a memory allocation error occurs during 4140** [sqlite3_aggregate_context(C,N)] then the function returns 0. 4141** 4142** {H16215} Second and subsequent invocations of 4143** [sqlite3_aggregate_context(C,N)] for the same context pointer C 4144** ignore the N parameter and return a pointer to the same 4145** block of memory returned by the first invocation. 4146** 4147** {H16217} The memory allocated by [sqlite3_aggregate_context(C,N)] is 4148** automatically freed on the next call to [sqlite3_reset()] 4149** or [sqlite3_finalize()] for the [prepared statement] containing 4150** the aggregate function associated with context C. 4151*/ 4152void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); 4153 4154/* 4155** CAPI3REF: User Data For Functions {H16240} <S20200> 4156** 4157** The sqlite3_user_data() interface returns a copy of 4158** the pointer that was the pUserData parameter (the 5th parameter) 4159** of the [sqlite3_create_function()] 4160** and [sqlite3_create_function16()] routines that originally 4161** registered the application defined function. {END} 4162** 4163** This routine must be called from the same thread in which 4164** the application-defined function is running. 4165** 4166** INVARIANTS: 4167** 4168** {H16243} The [sqlite3_user_data(C)] interface returns a copy of the 4169** P pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)] 4170** or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that 4171** registered the SQL function associated with [sqlite3_context] C. 4172*/ 4173void *sqlite3_user_data(sqlite3_context*); 4174 4175/* 4176** CAPI3REF: Database Connection For Functions {H16250} <S60600><S20200> 4177** 4178** The sqlite3_context_db_handle() interface returns a copy of 4179** the pointer to the [database connection] (the 1st parameter) 4180** of the [sqlite3_create_function()] 4181** and [sqlite3_create_function16()] routines that originally 4182** registered the application defined function. 4183** 4184** INVARIANTS: 4185** 4186** {H16253} The [sqlite3_context_db_handle(C)] interface returns a copy of the 4187** D pointer from the [sqlite3_create_function(D,X,N,E,P,F,S,L)] 4188** or [sqlite3_create_function16(D,X,N,E,P,F,S,L)] call that 4189** registered the SQL function associated with [sqlite3_context] C. 4190*/ 4191sqlite3 *sqlite3_context_db_handle(sqlite3_context*); 4192 4193/* 4194** CAPI3REF: Function Auxiliary Data {H16270} <S20200> 4195** 4196** The following two functions may be used by scalar SQL functions to 4197** associate metadata with argument values. If the same value is passed to 4198** multiple invocations of the same SQL function during query execution, under 4199** some circumstances the associated metadata may be preserved. This may 4200** be used, for example, to add a regular-expression matching scalar 4201** function. The compiled version of the regular expression is stored as 4202** metadata associated with the SQL value passed as the regular expression 4203** pattern. The compiled regular expression can be reused on multiple 4204** invocations of the same function so that the original pattern string 4205** does not need to be recompiled on each invocation. 4206** 4207** The sqlite3_get_auxdata() interface returns a pointer to the metadata 4208** associated by the sqlite3_set_auxdata() function with the Nth argument 4209** value to the application-defined function. If no metadata has been ever 4210** been set for the Nth argument of the function, or if the corresponding 4211** function parameter has changed since the meta-data was set, 4212** then sqlite3_get_auxdata() returns a NULL pointer. 4213** 4214** The sqlite3_set_auxdata() interface saves the metadata 4215** pointed to by its 3rd parameter as the metadata for the N-th 4216** argument of the application-defined function. Subsequent 4217** calls to sqlite3_get_auxdata() might return this data, if it has 4218** not been destroyed. 4219** If it is not NULL, SQLite will invoke the destructor 4220** function given by the 4th parameter to sqlite3_set_auxdata() on 4221** the metadata when the corresponding function parameter changes 4222** or when the SQL statement completes, whichever comes first. 4223** 4224** SQLite is free to call the destructor and drop metadata on any 4225** parameter of any function at any time. The only guarantee is that 4226** the destructor will be called before the metadata is dropped. 4227** 4228** In practice, metadata is preserved between function calls for 4229** expressions that are constant at compile time. This includes literal 4230** values and SQL variables. 4231** 4232** These routines must be called from the same thread in which 4233** the SQL function is running. 4234** 4235** INVARIANTS: 4236** 4237** {H16272} The [sqlite3_get_auxdata(C,N)] interface returns a pointer 4238** to metadata associated with the Nth parameter of the SQL function 4239** whose context is C, or NULL if there is no metadata associated 4240** with that parameter. 4241** 4242** {H16274} The [sqlite3_set_auxdata(C,N,P,D)] interface assigns a metadata 4243** pointer P to the Nth parameter of the SQL function with context C. 4244** 4245** {H16276} SQLite will invoke the destructor D with a single argument 4246** which is the metadata pointer P following a call to 4247** [sqlite3_set_auxdata(C,N,P,D)] when SQLite ceases to hold 4248** the metadata. 4249** 4250** {H16277} SQLite ceases to hold metadata for an SQL function parameter 4251** when the value of that parameter changes. 4252** 4253** {H16278} When [sqlite3_set_auxdata(C,N,P,D)] is invoked, the destructor 4254** is called for any prior metadata associated with the same function 4255** context C and parameter N. 4256** 4257** {H16279} SQLite will call destructors for any metadata it is holding 4258** in a particular [prepared statement] S when either 4259** [sqlite3_reset(S)] or [sqlite3_finalize(S)] is called. 4260*/ 4261void *sqlite3_get_auxdata(sqlite3_context*, int N); 4262void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); 4263 4264 4265/* 4266** CAPI3REF: Constants Defining Special Destructor Behavior {H10280} <S30100> 4267** 4268** These are special values for the destructor that is passed in as the 4269** final argument to routines like [sqlite3_result_blob()]. If the destructor 4270** argument is SQLITE_STATIC, it means that the content pointer is constant 4271** and will never change. It does not need to be destroyed. The 4272** SQLITE_TRANSIENT value means that the content will likely change in 4273** the near future and that SQLite should make its own private copy of 4274** the content before returning. 4275** 4276** The typedef is necessary to work around problems in certain 4277** C++ compilers. See ticket #2191. 4278*/ 4279typedef void (*sqlite3_destructor_type)(void*); 4280#define SQLITE_STATIC ((sqlite3_destructor_type)0) 4281#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) 4282 4283/* 4284** CAPI3REF: Setting The Result Of An SQL Function {H16400} <S20200> 4285** 4286** These routines are used by the xFunc or xFinal callbacks that 4287** implement SQL functions and aggregates. See 4288** [sqlite3_create_function()] and [sqlite3_create_function16()] 4289** for additional information. 4290** 4291** These functions work very much like the [parameter binding] family of 4292** functions used to bind values to host parameters in prepared statements. 4293** Refer to the [SQL parameter] documentation for additional information. 4294** 4295** The sqlite3_result_blob() interface sets the result from 4296** an application-defined function to be the BLOB whose content is pointed 4297** to by the second parameter and which is N bytes long where N is the 4298** third parameter. 4299** 4300** The sqlite3_result_zeroblob() interfaces set the result of 4301** the application-defined function to be a BLOB containing all zero 4302** bytes and N bytes in size, where N is the value of the 2nd parameter. 4303** 4304** The sqlite3_result_double() interface sets the result from 4305** an application-defined function to be a floating point value specified 4306** by its 2nd argument. 4307** 4308** The sqlite3_result_error() and sqlite3_result_error16() functions 4309** cause the implemented SQL function to throw an exception. 4310** SQLite uses the string pointed to by the 4311** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() 4312** as the text of an error message. SQLite interprets the error 4313** message string from sqlite3_result_error() as UTF-8. SQLite 4314** interprets the string from sqlite3_result_error16() as UTF-16 in native 4315** byte order. If the third parameter to sqlite3_result_error() 4316** or sqlite3_result_error16() is negative then SQLite takes as the error 4317** message all text up through the first zero character. 4318** If the third parameter to sqlite3_result_error() or 4319** sqlite3_result_error16() is non-negative then SQLite takes that many 4320** bytes (not characters) from the 2nd parameter as the error message. 4321** The sqlite3_result_error() and sqlite3_result_error16() 4322** routines make a private copy of the error message text before 4323** they return. Hence, the calling function can deallocate or 4324** modify the text after they return without harm. 4325** The sqlite3_result_error_code() function changes the error code 4326** returned by SQLite as a result of an error in a function. By default, 4327** the error code is SQLITE_ERROR. A subsequent call to sqlite3_result_error() 4328** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. 4329** 4330** The sqlite3_result_toobig() interface causes SQLite to throw an error 4331** indicating that a string or BLOB is to long to represent. 4332** 4333** The sqlite3_result_nomem() interface causes SQLite to throw an error 4334** indicating that a memory allocation failed. 4335** 4336** The sqlite3_result_int() interface sets the return value 4337** of the application-defined function to be the 32-bit signed integer 4338** value given in the 2nd argument. 4339** The sqlite3_result_int64() interface sets the return value 4340** of the application-defined function to be the 64-bit signed integer 4341** value given in the 2nd argument. 4342** 4343** The sqlite3_result_null() interface sets the return value 4344** of the application-defined function to be NULL. 4345** 4346** The sqlite3_result_text(), sqlite3_result_text16(), 4347** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces 4348** set the return value of the application-defined function to be 4349** a text string which is represented as UTF-8, UTF-16 native byte order, 4350** UTF-16 little endian, or UTF-16 big endian, respectively. 4351** SQLite takes the text result from the application from 4352** the 2nd parameter of the sqlite3_result_text* interfaces. 4353** If the 3rd parameter to the sqlite3_result_text* interfaces 4354** is negative, then SQLite takes result text from the 2nd parameter 4355** through the first zero character. 4356** If the 3rd parameter to the sqlite3_result_text* interfaces 4357** is non-negative, then as many bytes (not characters) of the text 4358** pointed to by the 2nd parameter are taken as the application-defined 4359** function result. 4360** If the 4th parameter to the sqlite3_result_text* interfaces 4361** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that 4362** function as the destructor on the text or BLOB result when it has 4363** finished using that result. 4364** If the 4th parameter to the sqlite3_result_text* interfaces or 4365** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite 4366** assumes that the text or BLOB result is in constant space and does not 4367** copy the it or call a destructor when it has finished using that result. 4368** If the 4th parameter to the sqlite3_result_text* interfaces 4369** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT 4370** then SQLite makes a copy of the result into space obtained from 4371** from [sqlite3_malloc()] before it returns. 4372** 4373** The sqlite3_result_value() interface sets the result of 4374** the application-defined function to be a copy the 4375** [unprotected sqlite3_value] object specified by the 2nd parameter. The 4376** sqlite3_result_value() interface makes a copy of the [sqlite3_value] 4377** so that the [sqlite3_value] specified in the parameter may change or 4378** be deallocated after sqlite3_result_value() returns without harm. 4379** A [protected sqlite3_value] object may always be used where an 4380** [unprotected sqlite3_value] object is required, so either 4381** kind of [sqlite3_value] object can be used with this interface. 4382** 4383** If these routines are called from within the different thread 4384** than the one containing the application-defined function that received 4385** the [sqlite3_context] pointer, the results are undefined. 4386** 4387** INVARIANTS: 4388** 4389** {H16403} The default return value from any SQL function is NULL. 4390** 4391** {H16406} The [sqlite3_result_blob(C,V,N,D)] interface changes the 4392** return value of function C to be a BLOB that is N bytes 4393** in length and with content pointed to by V. 4394** 4395** {H16409} The [sqlite3_result_double(C,V)] interface changes the 4396** return value of function C to be the floating point value V. 4397** 4398** {H16412} The [sqlite3_result_error(C,V,N)] interface changes the return 4399** value of function C to be an exception with error code 4400** [SQLITE_ERROR] and a UTF-8 error message copied from V up to the 4401** first zero byte or until N bytes are read if N is positive. 4402** 4403** {H16415} The [sqlite3_result_error16(C,V,N)] interface changes the return 4404** value of function C to be an exception with error code 4405** [SQLITE_ERROR] and a UTF-16 native byte order error message 4406** copied from V up to the first zero terminator or until N bytes 4407** are read if N is positive. 4408** 4409** {H16418} The [sqlite3_result_error_toobig(C)] interface changes the return 4410** value of the function C to be an exception with error code 4411** [SQLITE_TOOBIG] and an appropriate error message. 4412** 4413** {H16421} The [sqlite3_result_error_nomem(C)] interface changes the return 4414** value of the function C to be an exception with error code 4415** [SQLITE_NOMEM] and an appropriate error message. 4416** 4417** {H16424} The [sqlite3_result_error_code(C,E)] interface changes the return 4418** value of the function C to be an exception with error code E. 4419** The error message text is unchanged. 4420** 4421** {H16427} The [sqlite3_result_int(C,V)] interface changes the 4422** return value of function C to be the 32-bit integer value V. 4423** 4424** {H16430} The [sqlite3_result_int64(C,V)] interface changes the 4425** return value of function C to be the 64-bit integer value V. 4426** 4427** {H16433} The [sqlite3_result_null(C)] interface changes the 4428** return value of function C to be NULL. 4429** 4430** {H16436} The [sqlite3_result_text(C,V,N,D)] interface changes the 4431** return value of function C to be the UTF-8 string 4432** V up to the first zero if N is negative 4433** or the first N bytes of V if N is non-negative. 4434** 4435** {H16439} The [sqlite3_result_text16(C,V,N,D)] interface changes the 4436** return value of function C to be the UTF-16 native byte order 4437** string V up to the first zero if N is negative 4438** or the first N bytes of V if N is non-negative. 4439** 4440** {H16442} The [sqlite3_result_text16be(C,V,N,D)] interface changes the 4441** return value of function C to be the UTF-16 big-endian 4442** string V up to the first zero if N is negative 4443** or the first N bytes or V if N is non-negative. 4444** 4445** {H16445} The [sqlite3_result_text16le(C,V,N,D)] interface changes the 4446** return value of function C to be the UTF-16 little-endian 4447** string V up to the first zero if N is negative 4448** or the first N bytes of V if N is non-negative. 4449** 4450** {H16448} The [sqlite3_result_value(C,V)] interface changes the 4451** return value of function C to be the [unprotected sqlite3_value] 4452** object V. 4453** 4454** {H16451} The [sqlite3_result_zeroblob(C,N)] interface changes the 4455** return value of function C to be an N-byte BLOB of all zeros. 4456** 4457** {H16454} The [sqlite3_result_error()] and [sqlite3_result_error16()] 4458** interfaces make a copy of their error message strings before 4459** returning. 4460** 4461** {H16457} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)], 4462** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)], 4463** [sqlite3_result_text16be(C,V,N,D)], or 4464** [sqlite3_result_text16le(C,V,N,D)] is the constant [SQLITE_STATIC] 4465** then no destructor is ever called on the pointer V and SQLite 4466** assumes that V is immutable. 4467** 4468** {H16460} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)], 4469** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)], 4470** [sqlite3_result_text16be(C,V,N,D)], or 4471** [sqlite3_result_text16le(C,V,N,D)] is the constant 4472** [SQLITE_TRANSIENT] then the interfaces makes a copy of the 4473** content of V and retains the copy. 4474** 4475** {H16463} If the D destructor parameter to [sqlite3_result_blob(C,V,N,D)], 4476** [sqlite3_result_text(C,V,N,D)], [sqlite3_result_text16(C,V,N,D)], 4477** [sqlite3_result_text16be(C,V,N,D)], or 4478** [sqlite3_result_text16le(C,V,N,D)] is some value other than 4479** the constants [SQLITE_STATIC] and [SQLITE_TRANSIENT] then 4480** SQLite will invoke the destructor D with V as its only argument 4481** when it has finished with the V value. 4482*/ 4483void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); 4484void sqlite3_result_double(sqlite3_context*, double); 4485void sqlite3_result_error(sqlite3_context*, const char*, int); 4486void sqlite3_result_error16(sqlite3_context*, const void*, int); 4487void sqlite3_result_error_toobig(sqlite3_context*); 4488void sqlite3_result_error_nomem(sqlite3_context*); 4489void sqlite3_result_error_code(sqlite3_context*, int); 4490void sqlite3_result_int(sqlite3_context*, int); 4491void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); 4492void sqlite3_result_null(sqlite3_context*); 4493void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); 4494void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); 4495void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); 4496void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); 4497void sqlite3_result_value(sqlite3_context*, sqlite3_value*); 4498void sqlite3_result_zeroblob(sqlite3_context*, int n); 4499 4500/* 4501** CAPI3REF: Define New Collating Sequences {H16600} <S20300> 4502** 4503** These functions are used to add new collation sequences to the 4504** [database connection] specified as the first argument. 4505** 4506** The name of the new collation sequence is specified as a UTF-8 string 4507** for sqlite3_create_collation() and sqlite3_create_collation_v2() 4508** and a UTF-16 string for sqlite3_create_collation16(). In all cases 4509** the name is passed as the second function argument. 4510** 4511** The third argument may be one of the constants [SQLITE_UTF8], 4512** [SQLITE_UTF16LE] or [SQLITE_UTF16BE], indicating that the user-supplied 4513** routine expects to be passed pointers to strings encoded using UTF-8, 4514** UTF-16 little-endian, or UTF-16 big-endian, respectively. The 4515** third argument might also be [SQLITE_UTF16_ALIGNED] to indicate that 4516** the routine expects pointers to 16-bit word aligned strings 4517** of UTF-16 in the native byte order of the host computer. 4518** 4519** A pointer to the user supplied routine must be passed as the fifth 4520** argument. If it is NULL, this is the same as deleting the collation 4521** sequence (so that SQLite cannot call it anymore). 4522** Each time the application supplied function is invoked, it is passed 4523** as its first parameter a copy of the void* passed as the fourth argument 4524** to sqlite3_create_collation() or sqlite3_create_collation16(). 4525** 4526** The remaining arguments to the application-supplied routine are two strings, 4527** each represented by a (length, data) pair and encoded in the encoding 4528** that was passed as the third argument when the collation sequence was 4529** registered. {END} The application defined collation routine should 4530** return negative, zero or positive if the first string is less than, 4531** equal to, or greater than the second string. i.e. (STRING1 - STRING2). 4532** 4533** The sqlite3_create_collation_v2() works like sqlite3_create_collation() 4534** except that it takes an extra argument which is a destructor for 4535** the collation. The destructor is called when the collation is 4536** destroyed and is passed a copy of the fourth parameter void* pointer 4537** of the sqlite3_create_collation_v2(). 4538** Collations are destroyed when they are overridden by later calls to the 4539** collation creation functions or when the [database connection] is closed 4540** using [sqlite3_close()]. 4541** 4542** INVARIANTS: 4543** 4544** {H16603} A successful call to the 4545** [sqlite3_create_collation_v2(B,X,E,P,F,D)] interface 4546** registers function F as the comparison function used to 4547** implement collation X on the [database connection] B for 4548** databases having encoding E. 4549** 4550** {H16604} SQLite understands the X parameter to 4551** [sqlite3_create_collation_v2(B,X,E,P,F,D)] as a zero-terminated 4552** UTF-8 string in which case is ignored for ASCII characters and 4553** is significant for non-ASCII characters. 4554** 4555** {H16606} Successive calls to [sqlite3_create_collation_v2(B,X,E,P,F,D)] 4556** with the same values for B, X, and E, override prior values 4557** of P, F, and D. 4558** 4559** {H16609} If the destructor D in [sqlite3_create_collation_v2(B,X,E,P,F,D)] 4560** is not NULL then it is called with argument P when the 4561** collating function is dropped by SQLite. 4562** 4563** {H16612} A collating function is dropped when it is overloaded. 4564** 4565** {H16615} A collating function is dropped when the database connection 4566** is closed using [sqlite3_close()]. 4567** 4568** {H16618} The pointer P in [sqlite3_create_collation_v2(B,X,E,P,F,D)] 4569** is passed through as the first parameter to the comparison 4570** function F for all subsequent invocations of F. 4571** 4572** {H16621} A call to [sqlite3_create_collation(B,X,E,P,F)] is exactly 4573** the same as a call to [sqlite3_create_collation_v2()] with 4574** the same parameters and a NULL destructor. 4575** 4576** {H16624} Following a [sqlite3_create_collation_v2(B,X,E,P,F,D)], 4577** SQLite uses the comparison function F for all text comparison 4578** operations on the [database connection] B on text values that 4579** use the collating sequence named X. 4580** 4581** {H16627} The [sqlite3_create_collation16(B,X,E,P,F)] works the same 4582** as [sqlite3_create_collation(B,X,E,P,F)] except that the 4583** collation name X is understood as UTF-16 in native byte order 4584** instead of UTF-8. 4585** 4586** {H16630} When multiple comparison functions are available for the same 4587** collating sequence, SQLite chooses the one whose text encoding 4588** requires the least amount of conversion from the default 4589** text encoding of the database. 4590*/ 4591int sqlite3_create_collation( 4592 sqlite3*, 4593 const char *zName, 4594 int eTextRep, 4595 void*, 4596 int(*xCompare)(void*,int,const void*,int,const void*) 4597); 4598int sqlite3_create_collation_v2( 4599 sqlite3*, 4600 const char *zName, 4601 int eTextRep, 4602 void*, 4603 int(*xCompare)(void*,int,const void*,int,const void*), 4604 void(*xDestroy)(void*) 4605); 4606int sqlite3_create_collation16( 4607 sqlite3*, 4608 const void *zName, 4609 int eTextRep, 4610 void*, 4611 int(*xCompare)(void*,int,const void*,int,const void*) 4612); 4613 4614/* 4615** CAPI3REF: Collation Needed Callbacks {H16700} <S20300> 4616** 4617** To avoid having to register all collation sequences before a database 4618** can be used, a single callback function may be registered with the 4619** [database connection] to be called whenever an undefined collation 4620** sequence is required. 4621** 4622** If the function is registered using the sqlite3_collation_needed() API, 4623** then it is passed the names of undefined collation sequences as strings 4624** encoded in UTF-8. {H16703} If sqlite3_collation_needed16() is used, 4625** the names are passed as UTF-16 in machine native byte order. 4626** A call to either function replaces any existing callback. 4627** 4628** When the callback is invoked, the first argument passed is a copy 4629** of the second argument to sqlite3_collation_needed() or 4630** sqlite3_collation_needed16(). The second argument is the database 4631** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], 4632** or [SQLITE_UTF16LE], indicating the most desirable form of the collation 4633** sequence function required. The fourth parameter is the name of the 4634** required collation sequence. 4635** 4636** The callback function should register the desired collation using 4637** [sqlite3_create_collation()], [sqlite3_create_collation16()], or 4638** [sqlite3_create_collation_v2()]. 4639** 4640** INVARIANTS: 4641** 4642** {H16702} A successful call to [sqlite3_collation_needed(D,P,F)] 4643** or [sqlite3_collation_needed16(D,P,F)] causes 4644** the [database connection] D to invoke callback F with first 4645** parameter P whenever it needs a comparison function for a 4646** collating sequence that it does not know about. 4647** 4648** {H16704} Each successful call to [sqlite3_collation_needed()] or 4649** [sqlite3_collation_needed16()] overrides the callback registered 4650** on the same [database connection] by prior calls to either 4651** interface. 4652** 4653** {H16706} The name of the requested collating function passed in the 4654** 4th parameter to the callback is in UTF-8 if the callback 4655** was registered using [sqlite3_collation_needed()] and 4656** is in UTF-16 native byte order if the callback was 4657** registered using [sqlite3_collation_needed16()]. 4658*/ 4659int sqlite3_collation_needed( 4660 sqlite3*, 4661 void*, 4662 void(*)(void*,sqlite3*,int eTextRep,const char*) 4663); 4664int sqlite3_collation_needed16( 4665 sqlite3*, 4666 void*, 4667 void(*)(void*,sqlite3*,int eTextRep,const void*) 4668); 4669 4670/* 4671** Specify the key for an encrypted database. This routine should be 4672** called right after sqlite3_open(). 4673** 4674** The code to implement this API is not available in the public release 4675** of SQLite. 4676*/ 4677int sqlite3_key( 4678 sqlite3 *db, /* Database to be rekeyed */ 4679 const void *pKey, int nKey /* The key */ 4680); 4681 4682/* 4683** Change the key on an open database. If the current database is not 4684** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the 4685** database is decrypted. 4686** 4687** The code to implement this API is not available in the public release 4688** of SQLite. 4689*/ 4690int sqlite3_rekey( 4691 sqlite3 *db, /* Database to be rekeyed */ 4692 const void *pKey, int nKey /* The new key */ 4693); 4694 4695/* 4696** CAPI3REF: Suspend Execution For A Short Time {H10530} <S40410> 4697** 4698** The sqlite3_sleep() function causes the current thread to suspend execution 4699** for at least a number of milliseconds specified in its parameter. 4700** 4701** If the operating system does not support sleep requests with 4702** millisecond time resolution, then the time will be rounded up to 4703** the nearest second. The number of milliseconds of sleep actually 4704** requested from the operating system is returned. 4705** 4706** SQLite implements this interface by calling the xSleep() 4707** method of the default [sqlite3_vfs] object. 4708** 4709** INVARIANTS: 4710** 4711** {H10533} The [sqlite3_sleep(M)] interface invokes the xSleep 4712** method of the default [sqlite3_vfs|VFS] in order to 4713** suspend execution of the current thread for at least 4714** M milliseconds. 4715** 4716** {H10536} The [sqlite3_sleep(M)] interface returns the number of 4717** milliseconds of sleep actually requested of the operating 4718** system, which might be larger than the parameter M. 4719*/ 4720int sqlite3_sleep(int); 4721 4722/* 4723** CAPI3REF: Name Of The Folder Holding Temporary Files {H10310} <S20000> 4724** 4725** If this global variable is made to point to a string which is 4726** the name of a folder (a.k.a. directory), then all temporary files 4727** created by SQLite will be placed in that directory. If this variable 4728** is a NULL pointer, then SQLite performs a search for an appropriate 4729** temporary file directory. 4730** 4731** It is not safe to modify this variable once a [database connection] 4732** has been opened. It is intended that this variable be set once 4733** as part of process initialization and before any SQLite interface 4734** routines have been call and remain unchanged thereafter. 4735*/ 4736SQLITE_EXTERN char *sqlite3_temp_directory; 4737 4738/* 4739** CAPI3REF: Test For Auto-Commit Mode {H12930} <S60200> 4740** KEYWORDS: {autocommit mode} 4741** 4742** The sqlite3_get_autocommit() interface returns non-zero or 4743** zero if the given database connection is or is not in autocommit mode, 4744** respectively. Autocommit mode is on by default. 4745** Autocommit mode is disabled by a [BEGIN] statement. 4746** Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. 4747** 4748** If certain kinds of errors occur on a statement within a multi-statement 4749** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], 4750** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the 4751** transaction might be rolled back automatically. The only way to 4752** find out whether SQLite automatically rolled back the transaction after 4753** an error is to use this function. 4754** 4755** INVARIANTS: 4756** 4757** {H12931} The [sqlite3_get_autocommit(D)] interface returns non-zero or 4758** zero if the [database connection] D is or is not in autocommit 4759** mode, respectively. 4760** 4761** {H12932} Autocommit mode is on by default. 4762** 4763** {H12933} Autocommit mode is disabled by a successful [BEGIN] statement. 4764** 4765** {H12934} Autocommit mode is enabled by a successful [COMMIT] or [ROLLBACK] 4766** statement. 4767** 4768** ASSUMPTIONS: 4769** 4770** {A12936} If another thread changes the autocommit status of the database 4771** connection while this routine is running, then the return value 4772** is undefined. 4773*/ 4774int sqlite3_get_autocommit(sqlite3*); 4775 4776/* 4777** CAPI3REF: Find The Database Handle Of A Prepared Statement {H13120} <S60600> 4778** 4779** The sqlite3_db_handle interface returns the [database connection] handle 4780** to which a [prepared statement] belongs. The database handle returned by 4781** sqlite3_db_handle is the same database handle that was the first argument 4782** to the [sqlite3_prepare_v2()] call (or its variants) that was used to 4783** create the statement in the first place. 4784** 4785** INVARIANTS: 4786** 4787** {H13123} The [sqlite3_db_handle(S)] interface returns a pointer 4788** to the [database connection] associated with the 4789** [prepared statement] S. 4790*/ 4791sqlite3 *sqlite3_db_handle(sqlite3_stmt*); 4792 4793/* 4794** CAPI3REF: Find the next prepared statement {H13140} <S60600> 4795** 4796** This interface returns a pointer to the next [prepared statement] after 4797** pStmt associated with the [database connection] pDb. If pStmt is NULL 4798** then this interface returns a pointer to the first prepared statement 4799** associated with the database connection pDb. If no prepared statement 4800** satisfies the conditions of this routine, it returns NULL. 4801** 4802** INVARIANTS: 4803** 4804** {H13143} If D is a [database connection] that holds one or more 4805** unfinalized [prepared statements] and S is a NULL pointer, 4806** then [sqlite3_next_stmt(D, S)] routine shall return a pointer 4807** to one of the prepared statements associated with D. 4808** 4809** {H13146} If D is a [database connection] that holds no unfinalized 4810** [prepared statements] and S is a NULL pointer, then 4811** [sqlite3_next_stmt(D, S)] routine shall return a NULL pointer. 4812** 4813** {H13149} If S is a [prepared statement] in the [database connection] D 4814** and S is not the last prepared statement in D, then 4815** [sqlite3_next_stmt(D, S)] routine shall return a pointer 4816** to the next prepared statement in D after S. 4817** 4818** {H13152} If S is the last [prepared statement] in the 4819** [database connection] D then the [sqlite3_next_stmt(D, S)] 4820** routine shall return a NULL pointer. 4821** 4822** ASSUMPTIONS: 4823** 4824** {A13154} The [database connection] pointer D in a call to 4825** [sqlite3_next_stmt(D,S)] must refer to an open database 4826** connection and in particular must not be a NULL pointer. 4827*/ 4828sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); 4829 4830/* 4831** CAPI3REF: Commit And Rollback Notification Callbacks {H12950} <S60400> 4832** 4833** The sqlite3_commit_hook() interface registers a callback 4834** function to be invoked whenever a transaction is committed. 4835** Any callback set by a previous call to sqlite3_commit_hook() 4836** for the same database connection is overridden. 4837** The sqlite3_rollback_hook() interface registers a callback 4838** function to be invoked whenever a transaction is committed. 4839** Any callback set by a previous call to sqlite3_commit_hook() 4840** for the same database connection is overridden. 4841** The pArg argument is passed through to the callback. 4842** If the callback on a commit hook function returns non-zero, 4843** then the commit is converted into a rollback. 4844** 4845** If another function was previously registered, its 4846** pArg value is returned. Otherwise NULL is returned. 4847** 4848** Registering a NULL function disables the callback. 4849** 4850** For the purposes of this API, a transaction is said to have been 4851** rolled back if an explicit "ROLLBACK" statement is executed, or 4852** an error or constraint causes an implicit rollback to occur. 4853** The rollback callback is not invoked if a transaction is 4854** automatically rolled back because the database connection is closed. 4855** The rollback callback is not invoked if a transaction is 4856** rolled back because a commit callback returned non-zero. 4857** <todo> Check on this </todo> 4858** 4859** INVARIANTS: 4860** 4861** {H12951} The [sqlite3_commit_hook(D,F,P)] interface registers the 4862** callback function F to be invoked with argument P whenever 4863** a transaction commits on the [database connection] D. 4864** 4865** {H12952} The [sqlite3_commit_hook(D,F,P)] interface returns the P argument 4866** from the previous call with the same [database connection] D, 4867** or NULL on the first call for a particular database connection D. 4868** 4869** {H12953} Each call to [sqlite3_commit_hook()] overwrites the callback 4870** registered by prior calls. 4871** 4872** {H12954} If the F argument to [sqlite3_commit_hook(D,F,P)] is NULL 4873** then the commit hook callback is canceled and no callback 4874** is invoked when a transaction commits. 4875** 4876** {H12955} If the commit callback returns non-zero then the commit is 4877** converted into a rollback. 4878** 4879** {H12961} The [sqlite3_rollback_hook(D,F,P)] interface registers the 4880** callback function F to be invoked with argument P whenever 4881** a transaction rolls back on the [database connection] D. 4882** 4883** {H12962} The [sqlite3_rollback_hook(D,F,P)] interface returns the P 4884** argument from the previous call with the same 4885** [database connection] D, or NULL on the first call 4886** for a particular database connection D. 4887** 4888** {H12963} Each call to [sqlite3_rollback_hook()] overwrites the callback 4889** registered by prior calls. 4890** 4891** {H12964} If the F argument to [sqlite3_rollback_hook(D,F,P)] is NULL 4892** then the rollback hook callback is canceled and no callback 4893** is invoked when a transaction rolls back. 4894*/ 4895void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); 4896void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); 4897 4898/* 4899** CAPI3REF: Data Change Notification Callbacks {H12970} <S60400> 4900** 4901** The sqlite3_update_hook() interface registers a callback function 4902** with the [database connection] identified by the first argument 4903** to be invoked whenever a row is updated, inserted or deleted. 4904** Any callback set by a previous call to this function 4905** for the same database connection is overridden. 4906** 4907** The second argument is a pointer to the function to invoke when a 4908** row is updated, inserted or deleted. 4909** The first argument to the callback is a copy of the third argument 4910** to sqlite3_update_hook(). 4911** The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], 4912** or [SQLITE_UPDATE], depending on the operation that caused the callback 4913** to be invoked. 4914** The third and fourth arguments to the callback contain pointers to the 4915** database and table name containing the affected row. 4916** The final callback parameter is the rowid of the row. In the case of 4917** an update, this is the rowid after the update takes place. 4918** 4919** The update hook is not invoked when internal system tables are 4920** modified (i.e. sqlite_master and sqlite_sequence). 4921** 4922** If another function was previously registered, its pArg value 4923** is returned. Otherwise NULL is returned. 4924** 4925** INVARIANTS: 4926** 4927** {H12971} The [sqlite3_update_hook(D,F,P)] interface causes the callback 4928** function F to be invoked with first parameter P whenever 4929** a table row is modified, inserted, or deleted on 4930** the [database connection] D. 4931** 4932** {H12973} The [sqlite3_update_hook(D,F,P)] interface returns the value 4933** of P for the previous call on the same [database connection] D, 4934** or NULL for the first call. 4935** 4936** {H12975} If the update hook callback F in [sqlite3_update_hook(D,F,P)] 4937** is NULL then the no update callbacks are made. 4938** 4939** {H12977} Each call to [sqlite3_update_hook(D,F,P)] overrides prior calls 4940** to the same interface on the same [database connection] D. 4941** 4942** {H12979} The update hook callback is not invoked when internal system 4943** tables such as sqlite_master and sqlite_sequence are modified. 4944** 4945** {H12981} The second parameter to the update callback 4946** is one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], 4947** depending on the operation that caused the callback to be invoked. 4948** 4949** {H12983} The third and fourth arguments to the callback contain pointers 4950** to zero-terminated UTF-8 strings which are the names of the 4951** database and table that is being updated. 4952 4953** {H12985} The final callback parameter is the rowid of the row after 4954** the change occurs. 4955*/ 4956void *sqlite3_update_hook( 4957 sqlite3*, 4958 void(*)(void *,int ,char const *,char const *,sqlite3_int64), 4959 void* 4960); 4961 4962/* 4963** CAPI3REF: Enable Or Disable Shared Pager Cache {H10330} <S30900> 4964** KEYWORDS: {shared cache} {shared cache mode} 4965** 4966** This routine enables or disables the sharing of the database cache 4967** and schema data structures between [database connection | connections] 4968** to the same database. Sharing is enabled if the argument is true 4969** and disabled if the argument is false. 4970** 4971** Cache sharing is enabled and disabled for an entire process. {END} 4972** This is a change as of SQLite version 3.5.0. In prior versions of SQLite, 4973** sharing was enabled or disabled for each thread separately. 4974** 4975** The cache sharing mode set by this interface effects all subsequent 4976** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. 4977** Existing database connections continue use the sharing mode 4978** that was in effect at the time they were opened. 4979** 4980** Virtual tables cannot be used with a shared cache. When shared 4981** cache is enabled, the [sqlite3_create_module()] API used to register 4982** virtual tables will always return an error. 4983** 4984** This routine returns [SQLITE_OK] if shared cache was enabled or disabled 4985** successfully. An [error code] is returned otherwise. 4986** 4987** Shared cache is disabled by default. But this might change in 4988** future releases of SQLite. Applications that care about shared 4989** cache setting should set it explicitly. 4990** 4991** INVARIANTS: 4992** 4993** {H10331} A successful invocation of [sqlite3_enable_shared_cache(B)] 4994** will enable or disable shared cache mode for any subsequently 4995** created [database connection] in the same process. 4996** 4997** {H10336} When shared cache is enabled, the [sqlite3_create_module()] 4998** interface will always return an error. 4999** 5000** {H10337} The [sqlite3_enable_shared_cache(B)] interface returns 5001** [SQLITE_OK] if shared cache was enabled or disabled successfully. 5002** 5003** {H10339} Shared cache is disabled by default. 5004*/ 5005int sqlite3_enable_shared_cache(int); 5006 5007/* 5008** CAPI3REF: Attempt To Free Heap Memory {H17340} <S30220> 5009** 5010** The sqlite3_release_memory() interface attempts to free N bytes 5011** of heap memory by deallocating non-essential memory allocations 5012** held by the database library. {END} Memory used to cache database 5013** pages to improve performance is an example of non-essential memory. 5014** sqlite3_release_memory() returns the number of bytes actually freed, 5015** which might be more or less than the amount requested. 5016** 5017** INVARIANTS: 5018** 5019** {H17341} The [sqlite3_release_memory(N)] interface attempts to 5020** free N bytes of heap memory by deallocating non-essential 5021** memory allocations held by the database library. 5022** 5023** {H16342} The [sqlite3_release_memory(N)] returns the number 5024** of bytes actually freed, which might be more or less 5025** than the amount requested. 5026*/ 5027int sqlite3_release_memory(int); 5028 5029/* 5030** CAPI3REF: Impose A Limit On Heap Size {H17350} <S30220> 5031** 5032** The sqlite3_soft_heap_limit() interface places a "soft" limit 5033** on the amount of heap memory that may be allocated by SQLite. 5034** If an internal allocation is requested that would exceed the 5035** soft heap limit, [sqlite3_release_memory()] is invoked one or 5036** more times to free up some space before the allocation is performed. 5037** 5038** The limit is called "soft", because if [sqlite3_release_memory()] 5039** cannot free sufficient memory to prevent the limit from being exceeded, 5040** the memory is allocated anyway and the current operation proceeds. 5041** 5042** A negative or zero value for N means that there is no soft heap limit and 5043** [sqlite3_release_memory()] will only be called when memory is exhausted. 5044** The default value for the soft heap limit is zero. 5045** 5046** SQLite makes a best effort to honor the soft heap limit. 5047** But if the soft heap limit cannot be honored, execution will 5048** continue without error or notification. This is why the limit is 5049** called a "soft" limit. It is advisory only. 5050** 5051** Prior to SQLite version 3.5.0, this routine only constrained the memory 5052** allocated by a single thread - the same thread in which this routine 5053** runs. Beginning with SQLite version 3.5.0, the soft heap limit is 5054** applied to all threads. The value specified for the soft heap limit 5055** is an upper bound on the total memory allocation for all threads. In 5056** version 3.5.0 there is no mechanism for limiting the heap usage for 5057** individual threads. 5058** 5059** INVARIANTS: 5060** 5061** {H16351} The [sqlite3_soft_heap_limit(N)] interface places a soft limit 5062** of N bytes on the amount of heap memory that may be allocated 5063** using [sqlite3_malloc()] or [sqlite3_realloc()] at any point 5064** in time. 5065** 5066** {H16352} If a call to [sqlite3_malloc()] or [sqlite3_realloc()] would 5067** cause the total amount of allocated memory to exceed the 5068** soft heap limit, then [sqlite3_release_memory()] is invoked 5069** in an attempt to reduce the memory usage prior to proceeding 5070** with the memory allocation attempt. 5071** 5072** {H16353} Calls to [sqlite3_malloc()] or [sqlite3_realloc()] that trigger 5073** attempts to reduce memory usage through the soft heap limit 5074** mechanism continue even if the attempt to reduce memory 5075** usage is unsuccessful. 5076** 5077** {H16354} A negative or zero value for N in a call to 5078** [sqlite3_soft_heap_limit(N)] means that there is no soft 5079** heap limit and [sqlite3_release_memory()] will only be 5080** called when memory is completely exhausted. 5081** 5082** {H16355} The default value for the soft heap limit is zero. 5083** 5084** {H16358} Each call to [sqlite3_soft_heap_limit(N)] overrides the 5085** values set by all prior calls. 5086*/ 5087void sqlite3_soft_heap_limit(int); 5088 5089/* 5090** CAPI3REF: Extract Metadata About A Column Of A Table {H12850} <S60300> 5091** 5092** This routine returns metadata about a specific column of a specific 5093** database table accessible using the [database connection] handle 5094** passed as the first function argument. 5095** 5096** The column is identified by the second, third and fourth parameters to 5097** this function. The second parameter is either the name of the database 5098** (i.e. "main", "temp" or an attached database) containing the specified 5099** table or NULL. If it is NULL, then all attached databases are searched 5100** for the table using the same algorithm used by the database engine to 5101** resolve unqualified table references. 5102** 5103** The third and fourth parameters to this function are the table and column 5104** name of the desired column, respectively. Neither of these parameters 5105** may be NULL. 5106** 5107** Metadata is returned by writing to the memory locations passed as the 5th 5108** and subsequent parameters to this function. Any of these arguments may be 5109** NULL, in which case the corresponding element of metadata is omitted. 5110** 5111** <blockquote> 5112** <table border="1"> 5113** <tr><th> Parameter <th> Output<br>Type <th> Description 5114** 5115** <tr><td> 5th <td> const char* <td> Data type 5116** <tr><td> 6th <td> const char* <td> Name of default collation sequence 5117** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint 5118** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY 5119** <tr><td> 9th <td> int <td> True if column is AUTOINCREMENT 5120** </table> 5121** </blockquote> 5122** 5123** The memory pointed to by the character pointers returned for the 5124** declaration type and collation sequence is valid only until the next 5125** call to any SQLite API function. 5126** 5127** If the specified table is actually a view, an [error code] is returned. 5128** 5129** If the specified column is "rowid", "oid" or "_rowid_" and an 5130** INTEGER PRIMARY KEY column has been explicitly declared, then the output 5131** parameters are set for the explicitly declared column. If there is no 5132** explicitly declared INTEGER PRIMARY KEY column, then the output 5133** parameters are set as follows: 5134** 5135** <pre> 5136** data type: "INTEGER" 5137** collation sequence: "BINARY" 5138** not null: 0 5139** primary key: 1 5140** auto increment: 0 5141** </pre> 5142** 5143** This function may load one or more schemas from database files. If an 5144** error occurs during this process, or if the requested table or column 5145** cannot be found, an [error code] is returned and an error message left 5146** in the [database connection] (to be retrieved using sqlite3_errmsg()). 5147** 5148** This API is only available if the library was compiled with the 5149** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol defined. 5150*/ 5151int sqlite3_table_column_metadata( 5152 sqlite3 *db, /* Connection handle */ 5153 const char *zDbName, /* Database name or NULL */ 5154 const char *zTableName, /* Table name */ 5155 const char *zColumnName, /* Column name */ 5156 char const **pzDataType, /* OUTPUT: Declared data type */ 5157 char const **pzCollSeq, /* OUTPUT: Collation sequence name */ 5158 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ 5159 int *pPrimaryKey, /* OUTPUT: True if column part of PK */ 5160 int *pAutoinc /* OUTPUT: True if column is auto-increment */ 5161); 5162 5163/* 5164** CAPI3REF: Load An Extension {H12600} <S20500> 5165** 5166** This interface loads an SQLite extension library from the named file. 5167** 5168** {H12601} The sqlite3_load_extension() interface attempts to load an 5169** SQLite extension library contained in the file zFile. 5170** 5171** {H12602} The entry point is zProc. 5172** 5173** {H12603} zProc may be 0, in which case the name of the entry point 5174** defaults to "sqlite3_extension_init". 5175** 5176** {H12604} The sqlite3_load_extension() interface shall return 5177** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. 5178** 5179** {H12605} If an error occurs and pzErrMsg is not 0, then the 5180** [sqlite3_load_extension()] interface shall attempt to 5181** fill *pzErrMsg with error message text stored in memory 5182** obtained from [sqlite3_malloc()]. {END} The calling function 5183** should free this memory by calling [sqlite3_free()]. 5184** 5185** {H12606} Extension loading must be enabled using 5186** [sqlite3_enable_load_extension()] prior to calling this API, 5187** otherwise an error will be returned. 5188*/ 5189int sqlite3_load_extension( 5190 sqlite3 *db, /* Load the extension into this database connection */ 5191 const char *zFile, /* Name of the shared library containing extension */ 5192 const char *zProc, /* Entry point. Derived from zFile if 0 */ 5193 char **pzErrMsg /* Put error message here if not 0 */ 5194); 5195 5196/* 5197** CAPI3REF: Enable Or Disable Extension Loading {H12620} <S20500> 5198** 5199** So as not to open security holes in older applications that are 5200** unprepared to deal with extension loading, and as a means of disabling 5201** extension loading while evaluating user-entered SQL, the following API 5202** is provided to turn the [sqlite3_load_extension()] mechanism on and off. 5203** 5204** Extension loading is off by default. See ticket #1863. 5205** 5206** {H12621} Call the sqlite3_enable_load_extension() routine with onoff==1 5207** to turn extension loading on and call it with onoff==0 to turn 5208** it back off again. 5209** 5210** {H12622} Extension loading is off by default. 5211*/ 5212int sqlite3_enable_load_extension(sqlite3 *db, int onoff); 5213 5214/* 5215** CAPI3REF: Automatically Load An Extensions {H12640} <S20500> 5216** 5217** This API can be invoked at program startup in order to register 5218** one or more statically linked extensions that will be available 5219** to all new [database connections]. {END} 5220** 5221** This routine stores a pointer to the extension in an array that is 5222** obtained from [sqlite3_malloc()]. If you run a memory leak checker 5223** on your program and it reports a leak because of this array, invoke 5224** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory. 5225** 5226** {H12641} This function registers an extension entry point that is 5227** automatically invoked whenever a new [database connection] 5228** is opened using [sqlite3_open()], [sqlite3_open16()], 5229** or [sqlite3_open_v2()]. 5230** 5231** {H12642} Duplicate extensions are detected so calling this routine 5232** multiple times with the same extension is harmless. 5233** 5234** {H12643} This routine stores a pointer to the extension in an array 5235** that is obtained from [sqlite3_malloc()]. 5236** 5237** {H12644} Automatic extensions apply across all threads. 5238*/ 5239int sqlite3_auto_extension(void *xEntryPoint); 5240 5241/* 5242** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500> 5243** 5244** This function disables all previously registered automatic 5245** extensions. {END} It undoes the effect of all prior 5246** [sqlite3_auto_extension()] calls. 5247** 5248** {H12661} This function disables all previously registered 5249** automatic extensions. 5250** 5251** {H12662} This function disables automatic extensions in all threads. 5252*/ 5253void sqlite3_reset_auto_extension(void); 5254 5255/* 5256****** EXPERIMENTAL - subject to change without notice ************** 5257** 5258** The interface to the virtual-table mechanism is currently considered 5259** to be experimental. The interface might change in incompatible ways. 5260** If this is a problem for you, do not use the interface at this time. 5261** 5262** When the virtual-table mechanism stabilizes, we will declare the 5263** interface fixed, support it indefinitely, and remove this comment. 5264*/ 5265 5266/* 5267** Structures used by the virtual table interface 5268*/ 5269typedef struct sqlite3_vtab sqlite3_vtab; 5270typedef struct sqlite3_index_info sqlite3_index_info; 5271typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; 5272typedef struct sqlite3_module sqlite3_module; 5273 5274/* 5275** CAPI3REF: Virtual Table Object {H18000} <S20400> 5276** KEYWORDS: sqlite3_module 5277** EXPERIMENTAL 5278** 5279** A module is a class of virtual tables. Each module is defined 5280** by an instance of the following structure. This structure consists 5281** mostly of methods for the module. 5282** 5283** This interface is experimental and is subject to change or 5284** removal in future releases of SQLite. 5285*/ 5286struct sqlite3_module { 5287 int iVersion; 5288 int (*xCreate)(sqlite3*, void *pAux, 5289 int argc, const char *const*argv, 5290 sqlite3_vtab **ppVTab, char**); 5291 int (*xConnect)(sqlite3*, void *pAux, 5292 int argc, const char *const*argv, 5293 sqlite3_vtab **ppVTab, char**); 5294 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); 5295 int (*xDisconnect)(sqlite3_vtab *pVTab); 5296 int (*xDestroy)(sqlite3_vtab *pVTab); 5297 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); 5298 int (*xClose)(sqlite3_vtab_cursor*); 5299 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, 5300 int argc, sqlite3_value **argv); 5301 int (*xNext)(sqlite3_vtab_cursor*); 5302 int (*xEof)(sqlite3_vtab_cursor*); 5303 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); 5304 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); 5305 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); 5306 int (*xBegin)(sqlite3_vtab *pVTab); 5307 int (*xSync)(sqlite3_vtab *pVTab); 5308 int (*xCommit)(sqlite3_vtab *pVTab); 5309 int (*xRollback)(sqlite3_vtab *pVTab); 5310 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, 5311 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), 5312 void **ppArg); 5313 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); 5314}; 5315 5316/* 5317** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400> 5318** KEYWORDS: sqlite3_index_info 5319** EXPERIMENTAL 5320** 5321** The sqlite3_index_info structure and its substructures is used to 5322** pass information into and receive the reply from the xBestIndex 5323** method of an sqlite3_module. The fields under **Inputs** are the 5324** inputs to xBestIndex and are read-only. xBestIndex inserts its 5325** results into the **Outputs** fields. 5326** 5327** The aConstraint[] array records WHERE clause constraints of the form: 5328** 5329** <pre>column OP expr</pre> 5330** 5331** where OP is =, <, <=, >, or >=. The particular operator is 5332** stored in aConstraint[].op. The index of the column is stored in 5333** aConstraint[].iColumn. aConstraint[].usable is TRUE if the 5334** expr on the right-hand side can be evaluated (and thus the constraint 5335** is usable) and false if it cannot. 5336** 5337** The optimizer automatically inverts terms of the form "expr OP column" 5338** and makes other simplifications to the WHERE clause in an attempt to 5339** get as many WHERE clause terms into the form shown above as possible. 5340** The aConstraint[] array only reports WHERE clause terms in the correct 5341** form that refer to the particular virtual table being queried. 5342** 5343** Information about the ORDER BY clause is stored in aOrderBy[]. 5344** Each term of aOrderBy records a column of the ORDER BY clause. 5345** 5346** The xBestIndex method must fill aConstraintUsage[] with information 5347** about what parameters to pass to xFilter. If argvIndex>0 then 5348** the right-hand side of the corresponding aConstraint[] is evaluated 5349** and becomes the argvIndex-th entry in argv. If aConstraintUsage[].omit 5350** is true, then the constraint is assumed to be fully handled by the 5351** virtual table and is not checked again by SQLite. 5352** 5353** The idxNum and idxPtr values are recorded and passed into xFilter. 5354** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true. 5355** 5356** The orderByConsumed means that output from xFilter will occur in 5357** the correct order to satisfy the ORDER BY clause so that no separate 5358** sorting step is required. 5359** 5360** The estimatedCost value is an estimate of the cost of doing the 5361** particular lookup. A full scan of a table with N entries should have 5362** a cost of N. A binary search of a table of N entries should have a 5363** cost of approximately log(N). 5364** 5365** This interface is experimental and is subject to change or 5366** removal in future releases of SQLite. 5367*/ 5368struct sqlite3_index_info { 5369 /* Inputs */ 5370 int nConstraint; /* Number of entries in aConstraint */ 5371 struct sqlite3_index_constraint { 5372 int iColumn; /* Column on left-hand side of constraint */ 5373 unsigned char op; /* Constraint operator */ 5374 unsigned char usable; /* True if this constraint is usable */ 5375 int iTermOffset; /* Used internally - xBestIndex should ignore */ 5376 } *aConstraint; /* Table of WHERE clause constraints */ 5377 int nOrderBy; /* Number of terms in the ORDER BY clause */ 5378 struct sqlite3_index_orderby { 5379 int iColumn; /* Column number */ 5380 unsigned char desc; /* True for DESC. False for ASC. */ 5381 } *aOrderBy; /* The ORDER BY clause */ 5382 /* Outputs */ 5383 struct sqlite3_index_constraint_usage { 5384 int argvIndex; /* if >0, constraint is part of argv to xFilter */ 5385 unsigned char omit; /* Do not code a test for this constraint */ 5386 } *aConstraintUsage; 5387 int idxNum; /* Number used to identify the index */ 5388 char *idxStr; /* String, possibly obtained from sqlite3_malloc */ 5389 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ 5390 int orderByConsumed; /* True if output is already ordered */ 5391 double estimatedCost; /* Estimated cost of using this index */ 5392}; 5393#define SQLITE_INDEX_CONSTRAINT_EQ 2 5394#define SQLITE_INDEX_CONSTRAINT_GT 4 5395#define SQLITE_INDEX_CONSTRAINT_LE 8 5396#define SQLITE_INDEX_CONSTRAINT_LT 16 5397#define SQLITE_INDEX_CONSTRAINT_GE 32 5398#define SQLITE_INDEX_CONSTRAINT_MATCH 64 5399 5400/* 5401** CAPI3REF: Register A Virtual Table Implementation {H18200} <S20400> 5402** EXPERIMENTAL 5403** 5404** This routine is used to register a new module name with a 5405** [database connection]. Module names must be registered before 5406** creating new virtual tables on the module, or before using 5407** preexisting virtual tables of the module. 5408** 5409** This interface is experimental and is subject to change or 5410** removal in future releases of SQLite. 5411*/ 5412SQLITE_EXPERIMENTAL int sqlite3_create_module( 5413 sqlite3 *db, /* SQLite connection to register module with */ 5414 const char *zName, /* Name of the module */ 5415 const sqlite3_module *, /* Methods for the module */ 5416 void * /* Client data for xCreate/xConnect */ 5417); 5418 5419/* 5420** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400> 5421** EXPERIMENTAL 5422** 5423** This routine is identical to the [sqlite3_create_module()] method above, 5424** except that it allows a destructor function to be specified. It is 5425** even more experimental than the rest of the virtual tables API. 5426*/ 5427SQLITE_EXPERIMENTAL int sqlite3_create_module_v2( 5428 sqlite3 *db, /* SQLite connection to register module with */ 5429 const char *zName, /* Name of the module */ 5430 const sqlite3_module *, /* Methods for the module */ 5431 void *, /* Client data for xCreate/xConnect */ 5432 void(*xDestroy)(void*) /* Module destructor function */ 5433); 5434 5435/* 5436** CAPI3REF: Virtual Table Instance Object {H18010} <S20400> 5437** KEYWORDS: sqlite3_vtab 5438** EXPERIMENTAL 5439** 5440** Every module implementation uses a subclass of the following structure 5441** to describe a particular instance of the module. Each subclass will 5442** be tailored to the specific needs of the module implementation. 5443** The purpose of this superclass is to define certain fields that are 5444** common to all module implementations. 5445** 5446** Virtual tables methods can set an error message by assigning a 5447** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should 5448** take care that any prior string is freed by a call to [sqlite3_free()] 5449** prior to assigning a new string to zErrMsg. After the error message 5450** is delivered up to the client application, the string will be automatically 5451** freed by sqlite3_free() and the zErrMsg field will be zeroed. Note 5452** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field 5453** since virtual tables are commonly implemented in loadable extensions which 5454** do not have access to sqlite3MPrintf() or sqlite3Free(). 5455** 5456** This interface is experimental and is subject to change or 5457** removal in future releases of SQLite. 5458*/ 5459struct sqlite3_vtab { 5460 const sqlite3_module *pModule; /* The module for this virtual table */ 5461 int nRef; /* Used internally */ 5462 char *zErrMsg; /* Error message from sqlite3_mprintf() */ 5463 /* Virtual table implementations will typically add additional fields */ 5464}; 5465 5466/* 5467** CAPI3REF: Virtual Table Cursor Object {H18020} <S20400> 5468** KEYWORDS: sqlite3_vtab_cursor 5469** EXPERIMENTAL 5470** 5471** Every module implementation uses a subclass of the following structure 5472** to describe cursors that point into the virtual table and are used 5473** to loop through the virtual table. Cursors are created using the 5474** xOpen method of the module. Each module implementation will define 5475** the content of a cursor structure to suit its own needs. 5476** 5477** This superclass exists in order to define fields of the cursor that 5478** are common to all implementations. 5479** 5480** This interface is experimental and is subject to change or 5481** removal in future releases of SQLite. 5482*/ 5483struct sqlite3_vtab_cursor { 5484 sqlite3_vtab *pVtab; /* Virtual table of this cursor */ 5485 /* Virtual table implementations will typically add additional fields */ 5486}; 5487 5488/* 5489** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} <S20400> 5490** EXPERIMENTAL 5491** 5492** The xCreate and xConnect methods of a module use the following API 5493** to declare the format (the names and datatypes of the columns) of 5494** the virtual tables they implement. 5495** 5496** This interface is experimental and is subject to change or 5497** removal in future releases of SQLite. 5498*/ 5499SQLITE_EXPERIMENTAL int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable); 5500 5501/* 5502** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400> 5503** EXPERIMENTAL 5504** 5505** Virtual tables can provide alternative implementations of functions 5506** using the xFindFunction method. But global versions of those functions 5507** must exist in order to be overloaded. 5508** 5509** This API makes sure a global version of a function with a particular 5510** name and number of parameters exists. If no such function exists 5511** before this API is called, a new function is created. The implementation 5512** of the new function always causes an exception to be thrown. So 5513** the new function is not good for anything by itself. Its only 5514** purpose is to be a placeholder function that can be overloaded 5515** by virtual tables. 5516** 5517** This API should be considered part of the virtual table interface, 5518** which is experimental and subject to change. 5519*/ 5520SQLITE_EXPERIMENTAL int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); 5521 5522/* 5523** The interface to the virtual-table mechanism defined above (back up 5524** to a comment remarkably similar to this one) is currently considered 5525** to be experimental. The interface might change in incompatible ways. 5526** If this is a problem for you, do not use the interface at this time. 5527** 5528** When the virtual-table mechanism stabilizes, we will declare the 5529** interface fixed, support it indefinitely, and remove this comment. 5530** 5531****** EXPERIMENTAL - subject to change without notice ************** 5532*/ 5533 5534/* 5535** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230> 5536** KEYWORDS: {BLOB handle} {BLOB handles} 5537** 5538** An instance of this object represents an open BLOB on which 5539** [sqlite3_blob_open | incremental BLOB I/O] can be performed. 5540** Objects of this type are created by [sqlite3_blob_open()] 5541** and destroyed by [sqlite3_blob_close()]. 5542** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces 5543** can be used to read or write small subsections of the BLOB. 5544** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. 5545*/ 5546typedef struct sqlite3_blob sqlite3_blob; 5547 5548/* 5549** CAPI3REF: Open A BLOB For Incremental I/O {H17810} <S30230> 5550** 5551** This interfaces opens a [BLOB handle | handle] to the BLOB located 5552** in row iRow, column zColumn, table zTable in database zDb; 5553** in other words, the same BLOB that would be selected by: 5554** 5555** <pre> 5556** SELECT zColumn FROM zDb.zTable WHERE rowid = iRow; 5557** </pre> {END} 5558** 5559** If the flags parameter is non-zero, the the BLOB is opened for read 5560** and write access. If it is zero, the BLOB is opened for read access. 5561** 5562** Note that the database name is not the filename that contains 5563** the database but rather the symbolic name of the database that 5564** is assigned when the database is connected using [ATTACH]. 5565** For the main database file, the database name is "main". 5566** For TEMP tables, the database name is "temp". 5567** 5568** On success, [SQLITE_OK] is returned and the new [BLOB handle] is written 5569** to *ppBlob. Otherwise an [error code] is returned and any value written 5570** to *ppBlob should not be used by the caller. 5571** This function sets the [database connection] error code and message 5572** accessible via [sqlite3_errcode()] and [sqlite3_errmsg()]. 5573** 5574** If the row that a BLOB handle points to is modified by an 5575** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects 5576** then the BLOB handle is marked as "expired". 5577** This is true if any column of the row is changed, even a column 5578** other than the one the BLOB handle is open on. 5579** Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for 5580** a expired BLOB handle fail with an return code of [SQLITE_ABORT]. 5581** Changes written into a BLOB prior to the BLOB expiring are not 5582** rollback by the expiration of the BLOB. Such changes will eventually 5583** commit if the transaction continues to completion. 5584** 5585** INVARIANTS: 5586** 5587** {H17813} A successful invocation of the [sqlite3_blob_open(D,B,T,C,R,F,P)] 5588** interface shall open an [sqlite3_blob] object P on the BLOB 5589** in column C of the table T in the database B on 5590** the [database connection] D. 5591** 5592** {H17814} A successful invocation of [sqlite3_blob_open(D,...)] shall start 5593** a new transaction on the [database connection] D if that 5594** connection is not already in a transaction. 5595** 5596** {H17816} The [sqlite3_blob_open(D,B,T,C,R,F,P)] interface shall open 5597** the BLOB for read and write access if and only if the F 5598** parameter is non-zero. 5599** 5600** {H17819} The [sqlite3_blob_open()] interface shall return [SQLITE_OK] on 5601** success and an appropriate [error code] on failure. 5602** 5603** {H17821} If an error occurs during evaluation of [sqlite3_blob_open(D,...)] 5604** then subsequent calls to [sqlite3_errcode(D)], 5605** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return 5606** information appropriate for that error. 5607** 5608** {H17824} If any column in the row that a [sqlite3_blob] has open is 5609** changed by a separate [UPDATE] or [DELETE] statement or by 5610** an [ON CONFLICT] side effect, then the [sqlite3_blob] shall 5611** be marked as invalid. 5612*/ 5613int sqlite3_blob_open( 5614 sqlite3*, 5615 const char *zDb, 5616 const char *zTable, 5617 const char *zColumn, 5618 sqlite3_int64 iRow, 5619 int flags, 5620 sqlite3_blob **ppBlob 5621); 5622 5623/* 5624** CAPI3REF: Close A BLOB Handle {H17830} <S30230> 5625** 5626** Closes an open [BLOB handle]. 5627** 5628** Closing a BLOB shall cause the current transaction to commit 5629** if there are no other BLOBs, no pending prepared statements, and the 5630** database connection is in [autocommit mode]. 5631** If any writes were made to the BLOB, they might be held in cache 5632** until the close operation if they will fit. {END} 5633** 5634** Closing the BLOB often forces the changes 5635** out to disk and so if any I/O errors occur, they will likely occur 5636** at the time when the BLOB is closed. {H17833} Any errors that occur during 5637** closing are reported as a non-zero return value. 5638** 5639** The BLOB is closed unconditionally. Even if this routine returns 5640** an error code, the BLOB is still closed. 5641** 5642** INVARIANTS: 5643** 5644** {H17833} The [sqlite3_blob_close(P)] interface closes an [sqlite3_blob] 5645** object P previously opened using [sqlite3_blob_open()]. 5646** 5647** {H17836} Closing an [sqlite3_blob] object using 5648** [sqlite3_blob_close()] shall cause the current transaction to 5649** commit if there are no other open [sqlite3_blob] objects 5650** or [prepared statements] on the same [database connection] and 5651** the database connection is in [autocommit mode]. 5652** 5653** {H17839} The [sqlite3_blob_close(P)] interfaces shall close the 5654** [sqlite3_blob] object P unconditionally, even if 5655** [sqlite3_blob_close(P)] returns something other than [SQLITE_OK]. 5656*/ 5657int sqlite3_blob_close(sqlite3_blob *); 5658 5659/* 5660** CAPI3REF: Return The Size Of An Open BLOB {H17840} <S30230> 5661** 5662** Returns the size in bytes of the BLOB accessible via the open 5663** []BLOB handle] in its only argument. 5664** 5665** INVARIANTS: 5666** 5667** {H17843} The [sqlite3_blob_bytes(P)] interface returns the size 5668** in bytes of the BLOB that the [sqlite3_blob] object P 5669** refers to. 5670*/ 5671int sqlite3_blob_bytes(sqlite3_blob *); 5672 5673/* 5674** CAPI3REF: Read Data From A BLOB Incrementally {H17850} <S30230> 5675** 5676** This function is used to read data from an open [BLOB handle] into a 5677** caller-supplied buffer. N bytes of data are copied into buffer Z 5678** from the open BLOB, starting at offset iOffset. 5679** 5680** If offset iOffset is less than N bytes from the end of the BLOB, 5681** [SQLITE_ERROR] is returned and no data is read. If N or iOffset is 5682** less than zero, [SQLITE_ERROR] is returned and no data is read. 5683** 5684** An attempt to read from an expired [BLOB handle] fails with an 5685** error code of [SQLITE_ABORT]. 5686** 5687** On success, SQLITE_OK is returned. 5688** Otherwise, an [error code] or an [extended error code] is returned. 5689** 5690** INVARIANTS: 5691** 5692** {H17853} A successful invocation of [sqlite3_blob_read(P,Z,N,X)] 5693** shall reads N bytes of data out of the BLOB referenced by 5694** [BLOB handle] P beginning at offset X and store those bytes 5695** into buffer Z. 5696** 5697** {H17856} In [sqlite3_blob_read(P,Z,N,X)] if the size of the BLOB 5698** is less than N+X bytes, then the function shall leave the 5699** Z buffer unchanged and return [SQLITE_ERROR]. 5700** 5701** {H17859} In [sqlite3_blob_read(P,Z,N,X)] if X or N is less than zero 5702** then the function shall leave the Z buffer unchanged 5703** and return [SQLITE_ERROR]. 5704** 5705** {H17862} The [sqlite3_blob_read(P,Z,N,X)] interface shall return [SQLITE_OK] 5706** if N bytes are successfully read into buffer Z. 5707** 5708** {H17863} If the [BLOB handle] P is expired and X and N are within bounds 5709** then [sqlite3_blob_read(P,Z,N,X)] shall leave the Z buffer 5710** unchanged and return [SQLITE_ABORT]. 5711** 5712** {H17865} If the requested read could not be completed, 5713** the [sqlite3_blob_read(P,Z,N,X)] interface shall return an 5714** appropriate [error code] or [extended error code]. 5715** 5716** {H17868} If an error occurs during evaluation of [sqlite3_blob_read(P,...)] 5717** then subsequent calls to [sqlite3_errcode(D)], 5718** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return 5719** information appropriate for that error, where D is the 5720** [database connection] that was used to open the [BLOB handle] P. 5721*/ 5722int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); 5723 5724/* 5725** CAPI3REF: Write Data Into A BLOB Incrementally {H17870} <S30230> 5726** 5727** This function is used to write data into an open [BLOB handle] from a 5728** caller-supplied buffer. N bytes of data are copied from the buffer Z 5729** into the open BLOB, starting at offset iOffset. 5730** 5731** If the [BLOB handle] passed as the first argument was not opened for 5732** writing (the flags parameter to [sqlite3_blob_open()] was zero), 5733** this function returns [SQLITE_READONLY]. 5734** 5735** This function may only modify the contents of the BLOB; it is 5736** not possible to increase the size of a BLOB using this API. 5737** If offset iOffset is less than N bytes from the end of the BLOB, 5738** [SQLITE_ERROR] is returned and no data is written. If N is 5739** less than zero [SQLITE_ERROR] is returned and no data is written. 5740** 5741** An attempt to write to an expired [BLOB handle] fails with an 5742** error code of [SQLITE_ABORT]. Writes to the BLOB that occurred 5743** before the [BLOB handle] expired are not rolled back by the 5744** expiration of the handle, though of course those changes might 5745** have been overwritten by the statement that expired the BLOB handle 5746** or by other independent statements. 5747** 5748** On success, SQLITE_OK is returned. 5749** Otherwise, an [error code] or an [extended error code] is returned. 5750** 5751** INVARIANTS: 5752** 5753** {H17873} A successful invocation of [sqlite3_blob_write(P,Z,N,X)] 5754** shall write N bytes of data from buffer Z into the BLOB 5755** referenced by [BLOB handle] P beginning at offset X into 5756** the BLOB. 5757** 5758** {H17874} In the absence of other overridding changes, the changes 5759** written to a BLOB by [sqlite3_blob_write()] shall 5760** remain in effect after the associated [BLOB handle] expires. 5761** 5762** {H17875} If the [BLOB handle] P was opened for reading only then 5763** an invocation of [sqlite3_blob_write(P,Z,N,X)] shall leave 5764** the referenced BLOB unchanged and return [SQLITE_READONLY]. 5765** 5766** {H17876} If the size of the BLOB referenced by [BLOB handle] P is 5767** less than N+X bytes then [sqlite3_blob_write(P,Z,N,X)] shall 5768** leave the BLOB unchanged and return [SQLITE_ERROR]. 5769** 5770** {H17877} If the [BLOB handle] P is expired and X and N are within bounds 5771** then [sqlite3_blob_read(P,Z,N,X)] shall leave the BLOB 5772** unchanged and return [SQLITE_ABORT]. 5773** 5774** {H17879} If X or N are less than zero then [sqlite3_blob_write(P,Z,N,X)] 5775** shall leave the BLOB referenced by [BLOB handle] P unchanged 5776** and return [SQLITE_ERROR]. 5777** 5778** {H17882} The [sqlite3_blob_write(P,Z,N,X)] interface shall return 5779** [SQLITE_OK] if N bytes where successfully written into the BLOB. 5780** 5781** {H17885} If the requested write could not be completed, 5782** the [sqlite3_blob_write(P,Z,N,X)] interface shall return an 5783** appropriate [error code] or [extended error code]. 5784** 5785** {H17888} If an error occurs during evaluation of [sqlite3_blob_write(D,...)] 5786** then subsequent calls to [sqlite3_errcode(D)], 5787** [sqlite3_errmsg(D)], and [sqlite3_errmsg16(D)] shall return 5788** information appropriate for that error. 5789*/ 5790int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); 5791 5792/* 5793** CAPI3REF: Virtual File System Objects {H11200} <S20100> 5794** 5795** A virtual filesystem (VFS) is an [sqlite3_vfs] object 5796** that SQLite uses to interact 5797** with the underlying operating system. Most SQLite builds come with a 5798** single default VFS that is appropriate for the host computer. 5799** New VFSes can be registered and existing VFSes can be unregistered. 5800** The following interfaces are provided. 5801** 5802** The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. 5803** Names are case sensitive. 5804** Names are zero-terminated UTF-8 strings. 5805** If there is no match, a NULL pointer is returned. 5806** If zVfsName is NULL then the default VFS is returned. 5807** 5808** New VFSes are registered with sqlite3_vfs_register(). 5809** Each new VFS becomes the default VFS if the makeDflt flag is set. 5810** The same VFS can be registered multiple times without injury. 5811** To make an existing VFS into the default VFS, register it again 5812** with the makeDflt flag set. If two different VFSes with the 5813** same name are registered, the behavior is undefined. If a 5814** VFS is registered with a name that is NULL or an empty string, 5815** then the behavior is undefined. 5816** 5817** Unregister a VFS with the sqlite3_vfs_unregister() interface. 5818** If the default VFS is unregistered, another VFS is chosen as 5819** the default. The choice for the new VFS is arbitrary. 5820** 5821** INVARIANTS: 5822** 5823** {H11203} The [sqlite3_vfs_find(N)] interface returns a pointer to the 5824** registered [sqlite3_vfs] object whose name exactly matches 5825** the zero-terminated UTF-8 string N, or it returns NULL if 5826** there is no match. 5827** 5828** {H11206} If the N parameter to [sqlite3_vfs_find(N)] is NULL then 5829** the function returns a pointer to the default [sqlite3_vfs] 5830** object if there is one, or NULL if there is no default 5831** [sqlite3_vfs] object. 5832** 5833** {H11209} The [sqlite3_vfs_register(P,F)] interface registers the 5834** well-formed [sqlite3_vfs] object P using the name given 5835** by the zName field of the object. 5836** 5837** {H11212} Using the [sqlite3_vfs_register(P,F)] interface to register 5838** the same [sqlite3_vfs] object multiple times is a harmless no-op. 5839** 5840** {H11215} The [sqlite3_vfs_register(P,F)] interface makes the [sqlite3_vfs] 5841** object P the default [sqlite3_vfs] object if F is non-zero. 5842** 5843** {H11218} The [sqlite3_vfs_unregister(P)] interface unregisters the 5844** [sqlite3_vfs] object P so that it is no longer returned by 5845** subsequent calls to [sqlite3_vfs_find()]. 5846*/ 5847sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); 5848int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); 5849int sqlite3_vfs_unregister(sqlite3_vfs*); 5850 5851/* 5852** CAPI3REF: Mutexes {H17000} <S20000> 5853** 5854** The SQLite core uses these routines for thread 5855** synchronization. Though they are intended for internal 5856** use by SQLite, code that links against SQLite is 5857** permitted to use any of these routines. 5858** 5859** The SQLite source code contains multiple implementations 5860** of these mutex routines. An appropriate implementation 5861** is selected automatically at compile-time. The following 5862** implementations are available in the SQLite core: 5863** 5864** <ul> 5865** <li> SQLITE_MUTEX_OS2 5866** <li> SQLITE_MUTEX_PTHREAD 5867** <li> SQLITE_MUTEX_W32 5868** <li> SQLITE_MUTEX_NOOP 5869** </ul> 5870** 5871** The SQLITE_MUTEX_NOOP implementation is a set of routines 5872** that does no real locking and is appropriate for use in 5873** a single-threaded application. The SQLITE_MUTEX_OS2, 5874** SQLITE_MUTEX_PTHREAD, and SQLITE_MUTEX_W32 implementations 5875** are appropriate for use on OS/2, Unix, and Windows. 5876** 5877** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor 5878** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex 5879** implementation is included with the library. In this case the 5880** application must supply a custom mutex implementation using the 5881** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function 5882** before calling sqlite3_initialize() or any other public sqlite3_ 5883** function that calls sqlite3_initialize(). 5884** 5885** {H17011} The sqlite3_mutex_alloc() routine allocates a new 5886** mutex and returns a pointer to it. {H17012} If it returns NULL 5887** that means that a mutex could not be allocated. {H17013} SQLite 5888** will unwind its stack and return an error. {H17014} The argument 5889** to sqlite3_mutex_alloc() is one of these integer constants: 5890** 5891** <ul> 5892** <li> SQLITE_MUTEX_FAST 5893** <li> SQLITE_MUTEX_RECURSIVE 5894** <li> SQLITE_MUTEX_STATIC_MASTER 5895** <li> SQLITE_MUTEX_STATIC_MEM 5896** <li> SQLITE_MUTEX_STATIC_MEM2 5897** <li> SQLITE_MUTEX_STATIC_PRNG 5898** <li> SQLITE_MUTEX_STATIC_LRU 5899** <li> SQLITE_MUTEX_STATIC_LRU2 5900** </ul> 5901** 5902** {H17015} The first two constants cause sqlite3_mutex_alloc() to create 5903** a new mutex. The new mutex is recursive when SQLITE_MUTEX_RECURSIVE 5904** is used but not necessarily so when SQLITE_MUTEX_FAST is used. {END} 5905** The mutex implementation does not need to make a distinction 5906** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does 5907** not want to. {H17016} But SQLite will only request a recursive mutex in 5908** cases where it really needs one. {END} If a faster non-recursive mutex 5909** implementation is available on the host platform, the mutex subsystem 5910** might return such a mutex in response to SQLITE_MUTEX_FAST. 5911** 5912** {H17017} The other allowed parameters to sqlite3_mutex_alloc() each return 5913** a pointer to a static preexisting mutex. {END} Four static mutexes are 5914** used by the current version of SQLite. Future versions of SQLite 5915** may add additional static mutexes. Static mutexes are for internal 5916** use by SQLite only. Applications that use SQLite mutexes should 5917** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or 5918** SQLITE_MUTEX_RECURSIVE. 5919** 5920** {H17018} Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST 5921** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() 5922** returns a different mutex on every call. {H17034} But for the static 5923** mutex types, the same mutex is returned on every call that has 5924** the same type number. 5925** 5926** {H17019} The sqlite3_mutex_free() routine deallocates a previously 5927** allocated dynamic mutex. {H17020} SQLite is careful to deallocate every 5928** dynamic mutex that it allocates. {A17021} The dynamic mutexes must not be in 5929** use when they are deallocated. {A17022} Attempting to deallocate a static 5930** mutex results in undefined behavior. {H17023} SQLite never deallocates 5931** a static mutex. {END} 5932** 5933** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt 5934** to enter a mutex. {H17024} If another thread is already within the mutex, 5935** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return 5936** SQLITE_BUSY. {H17025} The sqlite3_mutex_try() interface returns [SQLITE_OK] 5937** upon successful entry. {H17026} Mutexes created using 5938** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. 5939** {H17027} In such cases the, 5940** mutex must be exited an equal number of times before another thread 5941** can enter. {A17028} If the same thread tries to enter any other 5942** kind of mutex more than once, the behavior is undefined. 5943** {H17029} SQLite will never exhibit 5944** such behavior in its own use of mutexes. 5945** 5946** Some systems (for example, Windows 95) do not support the operation 5947** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() 5948** will always return SQLITE_BUSY. {H17030} The SQLite core only ever uses 5949** sqlite3_mutex_try() as an optimization so this is acceptable behavior. 5950** 5951** {H17031} The sqlite3_mutex_leave() routine exits a mutex that was 5952** previously entered by the same thread. {A17032} The behavior 5953** is undefined if the mutex is not currently entered by the 5954** calling thread or is not currently allocated. {H17033} SQLite will 5955** never do either. {END} 5956** 5957** If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or 5958** sqlite3_mutex_leave() is a NULL pointer, then all three routines 5959** behave as no-ops. 5960** 5961** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. 5962*/ 5963sqlite3_mutex *sqlite3_mutex_alloc(int); 5964void sqlite3_mutex_free(sqlite3_mutex*); 5965void sqlite3_mutex_enter(sqlite3_mutex*); 5966int sqlite3_mutex_try(sqlite3_mutex*); 5967void sqlite3_mutex_leave(sqlite3_mutex*); 5968 5969/* 5970** CAPI3REF: Mutex Methods Object {H17120} <S20130> 5971** EXPERIMENTAL 5972** 5973** An instance of this structure defines the low-level routines 5974** used to allocate and use mutexes. 5975** 5976** Usually, the default mutex implementations provided by SQLite are 5977** sufficient, however the user has the option of substituting a custom 5978** implementation for specialized deployments or systems for which SQLite 5979** does not provide a suitable implementation. In this case, the user 5980** creates and populates an instance of this structure to pass 5981** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. 5982** Additionally, an instance of this structure can be used as an 5983** output variable when querying the system for the current mutex 5984** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. 5985** 5986** The xMutexInit method defined by this structure is invoked as 5987** part of system initialization by the sqlite3_initialize() function. 5988** {H17001} The xMutexInit routine shall be called by SQLite once for each 5989** effective call to [sqlite3_initialize()]. 5990** 5991** The xMutexEnd method defined by this structure is invoked as 5992** part of system shutdown by the sqlite3_shutdown() function. The 5993** implementation of this method is expected to release all outstanding 5994** resources obtained by the mutex methods implementation, especially 5995** those obtained by the xMutexInit method. {H17003} The xMutexEnd() 5996** interface shall be invoked once for each call to [sqlite3_shutdown()]. 5997** 5998** The remaining seven methods defined by this structure (xMutexAlloc, 5999** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and 6000** xMutexNotheld) implement the following interfaces (respectively): 6001** 6002** <ul> 6003** <li> [sqlite3_mutex_alloc()] </li> 6004** <li> [sqlite3_mutex_free()] </li> 6005** <li> [sqlite3_mutex_enter()] </li> 6006** <li> [sqlite3_mutex_try()] </li> 6007** <li> [sqlite3_mutex_leave()] </li> 6008** <li> [sqlite3_mutex_held()] </li> 6009** <li> [sqlite3_mutex_notheld()] </li> 6010** </ul> 6011** 6012** The only difference is that the public sqlite3_XXX functions enumerated 6013** above silently ignore any invocations that pass a NULL pointer instead 6014** of a valid mutex handle. The implementations of the methods defined 6015** by this structure are not required to handle this case, the results 6016** of passing a NULL pointer instead of a valid mutex handle are undefined 6017** (i.e. it is acceptable to provide an implementation that segfaults if 6018** it is passed a NULL pointer). 6019*/ 6020typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; 6021struct sqlite3_mutex_methods { 6022 int (*xMutexInit)(void); 6023 int (*xMutexEnd)(void); 6024 sqlite3_mutex *(*xMutexAlloc)(int); 6025 void (*xMutexFree)(sqlite3_mutex *); 6026 void (*xMutexEnter)(sqlite3_mutex *); 6027 int (*xMutexTry)(sqlite3_mutex *); 6028 void (*xMutexLeave)(sqlite3_mutex *); 6029 int (*xMutexHeld)(sqlite3_mutex *); 6030 int (*xMutexNotheld)(sqlite3_mutex *); 6031}; 6032 6033/* 6034** CAPI3REF: Mutex Verification Routines {H17080} <S20130> <S30800> 6035** 6036** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines 6037** are intended for use inside assert() statements. {H17081} The SQLite core 6038** never uses these routines except inside an assert() and applications 6039** are advised to follow the lead of the core. {H17082} The core only 6040** provides implementations for these routines when it is compiled 6041** with the SQLITE_DEBUG flag. {A17087} External mutex implementations 6042** are only required to provide these routines if SQLITE_DEBUG is 6043** defined and if NDEBUG is not defined. 6044** 6045** {H17083} These routines should return true if the mutex in their argument 6046** is held or not held, respectively, by the calling thread. 6047** 6048** {X17084} The implementation is not required to provided versions of these 6049** routines that actually work. If the implementation does not provide working 6050** versions of these routines, it should at least provide stubs that always 6051** return true so that one does not get spurious assertion failures. 6052** 6053** {H17085} If the argument to sqlite3_mutex_held() is a NULL pointer then 6054** the routine should return 1. {END} This seems counter-intuitive since 6055** clearly the mutex cannot be held if it does not exist. But the 6056** the reason the mutex does not exist is because the build is not 6057** using mutexes. And we do not want the assert() containing the 6058** call to sqlite3_mutex_held() to fail, so a non-zero return is 6059** the appropriate thing to do. {H17086} The sqlite3_mutex_notheld() 6060** interface should also return 1 when given a NULL pointer. 6061*/ 6062int sqlite3_mutex_held(sqlite3_mutex*); 6063int sqlite3_mutex_notheld(sqlite3_mutex*); 6064 6065/* 6066** CAPI3REF: Mutex Types {H17001} <H17000> 6067** 6068** The [sqlite3_mutex_alloc()] interface takes a single argument 6069** which is one of these integer constants. 6070** 6071** The set of static mutexes may change from one SQLite release to the 6072** next. Applications that override the built-in mutex logic must be 6073** prepared to accommodate additional static mutexes. 6074*/ 6075#define SQLITE_MUTEX_FAST 0 6076#define SQLITE_MUTEX_RECURSIVE 1 6077#define SQLITE_MUTEX_STATIC_MASTER 2 6078#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ 6079#define SQLITE_MUTEX_STATIC_MEM2 4 /* sqlite3_release_memory() */ 6080#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_random() */ 6081#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ 6082#define SQLITE_MUTEX_STATIC_LRU2 7 /* lru page list */ 6083 6084/* 6085** CAPI3REF: Low-Level Control Of Database Files {H11300} <S30800> 6086** 6087** {H11301} The [sqlite3_file_control()] interface makes a direct call to the 6088** xFileControl method for the [sqlite3_io_methods] object associated 6089** with a particular database identified by the second argument. {H11302} The 6090** name of the database is the name assigned to the database by the 6091** <a href="lang_attach.html">ATTACH</a> SQL command that opened the 6092** database. {H11303} To control the main database file, use the name "main" 6093** or a NULL pointer. {H11304} The third and fourth parameters to this routine 6094** are passed directly through to the second and third parameters of 6095** the xFileControl method. {H11305} The return value of the xFileControl 6096** method becomes the return value of this routine. 6097** 6098** {H11306} If the second parameter (zDbName) does not match the name of any 6099** open database file, then SQLITE_ERROR is returned. {H11307} This error 6100** code is not remembered and will not be recalled by [sqlite3_errcode()] 6101** or [sqlite3_errmsg()]. {A11308} The underlying xFileControl method might 6102** also return SQLITE_ERROR. {A11309} There is no way to distinguish between 6103** an incorrect zDbName and an SQLITE_ERROR return from the underlying 6104** xFileControl method. {END} 6105** 6106** See also: [SQLITE_FCNTL_LOCKSTATE] 6107*/ 6108int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); 6109 6110/* 6111** CAPI3REF: Testing Interface {H11400} <S30800> 6112** 6113** The sqlite3_test_control() interface is used to read out internal 6114** state of SQLite and to inject faults into SQLite for testing 6115** purposes. The first parameter is an operation code that determines 6116** the number, meaning, and operation of all subsequent parameters. 6117** 6118** This interface is not for use by applications. It exists solely 6119** for verifying the correct operation of the SQLite library. Depending 6120** on how the SQLite library is compiled, this interface might not exist. 6121** 6122** The details of the operation codes, their meanings, the parameters 6123** they take, and what they do are all subject to change without notice. 6124** Unlike most of the SQLite API, this function is not guaranteed to 6125** operate consistently from one release to the next. 6126*/ 6127int sqlite3_test_control(int op, ...); 6128 6129/* 6130** CAPI3REF: Testing Interface Operation Codes {H11410} <H11400> 6131** 6132** These constants are the valid operation code parameters used 6133** as the first argument to [sqlite3_test_control()]. 6134** 6135** These parameters and their meanings are subject to change 6136** without notice. These values are for testing purposes only. 6137** Applications should not use any of these parameters or the 6138** [sqlite3_test_control()] interface. 6139*/ 6140#define SQLITE_TESTCTRL_PRNG_SAVE 5 6141#define SQLITE_TESTCTRL_PRNG_RESTORE 6 6142#define SQLITE_TESTCTRL_PRNG_RESET 7 6143#define SQLITE_TESTCTRL_BITVEC_TEST 8 6144#define SQLITE_TESTCTRL_FAULT_INSTALL 9 6145#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 6146 6147/* 6148** CAPI3REF: SQLite Runtime Status {H17200} <S60200> 6149** EXPERIMENTAL 6150** 6151** This interface is used to retrieve runtime status information 6152** about the preformance of SQLite, and optionally to reset various 6153** highwater marks. The first argument is an integer code for 6154** the specific parameter to measure. Recognized integer codes 6155** are of the form [SQLITE_STATUS_MEMORY_USED | SQLITE_STATUS_...]. 6156** The current value of the parameter is returned into *pCurrent. 6157** The highest recorded value is returned in *pHighwater. If the 6158** resetFlag is true, then the highest record value is reset after 6159** *pHighwater is written. Some parameters do not record the highest 6160** value. For those parameters 6161** nothing is written into *pHighwater and the resetFlag is ignored. 6162** Other parameters record only the highwater mark and not the current 6163** value. For these latter parameters nothing is written into *pCurrent. 6164** 6165** This routine returns SQLITE_OK on success and a non-zero 6166** [error code] on failure. 6167** 6168** This routine is threadsafe but is not atomic. This routine can 6169** called while other threads are running the same or different SQLite 6170** interfaces. However the values returned in *pCurrent and 6171** *pHighwater reflect the status of SQLite at different points in time 6172** and it is possible that another thread might change the parameter 6173** in between the times when *pCurrent and *pHighwater are written. 6174** 6175** See also: [sqlite3_db_status()] 6176*/ 6177SQLITE_EXPERIMENTAL int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); 6178 6179/* 6180** CAPI3REF: Database Connection Status {H17201} <S60200> 6181** EXPERIMENTAL 6182** 6183** This interface is used to retrieve runtime status information 6184** about a single [database connection]. The first argument is the 6185** database connection object to be interrogated. The second argument 6186** is the parameter to interrogate. Currently, the only allowed value 6187** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED]. 6188** Additional options will likely appear in future releases of SQLite. 6189** 6190** The current value of the request parameter is written into *pCur 6191** and the highest instantaneous value is written into *pHiwtr. If 6192** the resetFlg is true, then the highest instantaneous value is 6193** reset back down to the current value. 6194** 6195** See also: [sqlite3_status()]. 6196*/ 6197SQLITE_EXPERIMENTAL int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); 6198 6199 6200int sqlite3_wsd_init(int N, int J); 6201void *sqlite3_wsd_find(void *K, int L); 6202 6203/* 6204** CAPI3REF: Status Parameters {H17250} <H17200> 6205** EXPERIMENTAL 6206** 6207** These integer constants designate various run-time status parameters 6208** that can be returned by [sqlite3_status()]. 6209** 6210** <dl> 6211** <dt>SQLITE_STATUS_MEMORY_USED</dt> 6212** <dd>This parameter is the current amount of memory checked out 6213** using [sqlite3_malloc()], either directly or indirectly. The 6214** figure includes calls made to [sqlite3_malloc()] by the application 6215** and internal memory usage by the SQLite library. Scratch memory 6216** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache 6217** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in 6218** this parameter. The amount returned is the sum of the allocation 6219** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd> 6220** 6221** <dt>SQLITE_STATUS_MALLOC_SIZE</dt> 6222** <dd>This parameter records the largest memory allocation request 6223** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their 6224** internal equivalents). Only the value returned in the 6225** *pHighwater parameter to [sqlite3_status()] is of interest. 6226** The value written into the *pCurrent parameter is undefined.</dd> 6227** 6228** <dt>SQLITE_STATUS_PAGECACHE_USED</dt> 6229** <dd>This parameter returns the number of pages used out of the 6230** [pagecache memory allocator] that was configured using 6231** [SQLITE_CONFIG_PAGECACHE]. The 6232** value returned is in pages, not in bytes.</dd> 6233** 6234** <dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> 6235** <dd>This parameter returns the number of bytes of page cache 6236** allocation which could not be statisfied by the [SQLITE_CONFIG_PAGECACHE] 6237** buffer and where forced to overflow to [sqlite3_malloc()]. The 6238** returned value includes allocations that overflowed because they 6239** where too large (they were larger than the "sz" parameter to 6240** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because 6241** no space was left in the page cache.</dd> 6242** 6243** <dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> 6244** <dd>This parameter records the largest memory allocation request 6245** handed to [pagecache memory allocator]. Only the value returned in the 6246** *pHighwater parameter to [sqlite3_status()] is of interest. 6247** The value written into the *pCurrent parameter is undefined.</dd> 6248** 6249** <dt>SQLITE_STATUS_SCRATCH_USED</dt> 6250** <dd>This parameter returns the number of allocations used out of the 6251** [scratch memory allocator] configured using 6252** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not 6253** in bytes. Since a single thread may only have one scratch allocation 6254** outstanding at time, this parameter also reports the number of threads 6255** using scratch memory at the same time.</dd> 6256** 6257** <dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> 6258** <dd>This parameter returns the number of bytes of scratch memory 6259** allocation which could not be statisfied by the [SQLITE_CONFIG_SCRATCH] 6260** buffer and where forced to overflow to [sqlite3_malloc()]. The values 6261** returned include overflows because the requested allocation was too 6262** larger (that is, because the requested allocation was larger than the 6263** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer 6264** slots were available. 6265** </dd> 6266** 6267** <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> 6268** <dd>This parameter records the largest memory allocation request 6269** handed to [scratch memory allocator]. Only the value returned in the 6270** *pHighwater parameter to [sqlite3_status()] is of interest. 6271** The value written into the *pCurrent parameter is undefined.</dd> 6272** 6273** <dt>SQLITE_STATUS_PARSER_STACK</dt> 6274** <dd>This parameter records the deepest parser stack. It is only 6275** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd> 6276** </dl> 6277** 6278** New status parameters may be added from time to time. 6279*/ 6280#define SQLITE_STATUS_MEMORY_USED 0 6281#define SQLITE_STATUS_PAGECACHE_USED 1 6282#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 6283#define SQLITE_STATUS_SCRATCH_USED 3 6284#define SQLITE_STATUS_SCRATCH_OVERFLOW 4 6285#define SQLITE_STATUS_MALLOC_SIZE 5 6286#define SQLITE_STATUS_PARSER_STACK 6 6287#define SQLITE_STATUS_PAGECACHE_SIZE 7 6288#define SQLITE_STATUS_SCRATCH_SIZE 8 6289 6290/* 6291** CAPI3REF: Status Parameters for database connections {H17275} <H17200> 6292** EXPERIMENTAL 6293** 6294** Status verbs for [sqlite3_db_status()]. 6295** 6296** <dl> 6297** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> 6298** <dd>This parameter returns the number of lookaside memory slots currently 6299** checked out.</dd> 6300** </dl> 6301*/ 6302#define SQLITE_DBSTATUS_LOOKASIDE_USED 0 6303 6304/* 6305** Undo the hack that converts floating point types to integer for 6306** builds on processors without floating point support. 6307*/ 6308#ifdef SQLITE_OMIT_FLOATING_POINT 6309# undef double 6310#endif 6311 6312#ifdef __cplusplus 6313} /* End of the 'extern "C"' block */ 6314#endif 6315#endif 6316