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. 14** 15** @(#) $Id: sqlite.h.in,v 1.60 2004/03/14 22:12:35 drh Exp $ 16*/ 17#ifndef _SQLITE_H_ 18#define _SQLITE_H_ 19#include <stdarg.h> /* Needed for the definition of va_list */ 20 21/* 22** Make sure we can call this stuff from C++. 23*/ 24#ifdef __cplusplus 25extern "C" { 26#endif 27 28/* 29** The version of the SQLite library. 30*/ 31#define SQLITE_VERSION "--VERS--" 32 33/* 34** The version string is also compiled into the library so that a program 35** can check to make sure that the lib*.a file and the *.h file are from 36** the same version. 37*/ 38extern const char sqlite_version[]; 39 40/* 41** The SQLITE_UTF8 macro is defined if the library expects to see 42** UTF-8 encoded data. The SQLITE_ISO8859 macro is defined if the 43** iso8859 encoded should be used. 44*/ 45#define SQLITE_--ENCODING-- 1 46 47/* 48** The following constant holds one of two strings, "UTF-8" or "iso8859", 49** depending on which character encoding the SQLite library expects to 50** see. The character encoding makes a difference for the LIKE and GLOB 51** operators and for the LENGTH() and SUBSTR() functions. 52*/ 53extern const char sqlite_encoding[]; 54 55/* 56** Each open sqlite database is represented by an instance of the 57** following opaque structure. 58*/ 59typedef struct sqlite sqlite; 60 61/* 62** A function to open a new sqlite database. 63** 64** If the database does not exist and mode indicates write 65** permission, then a new database is created. If the database 66** does not exist and mode does not indicate write permission, 67** then the open fails, an error message generated (if errmsg!=0) 68** and the function returns 0. 69** 70** If mode does not indicates user write permission, then the 71** database is opened read-only. 72** 73** The Truth: As currently implemented, all databases are opened 74** for writing all the time. Maybe someday we will provide the 75** ability to open a database readonly. The mode parameters is 76** provided in anticipation of that enhancement. 77*/ 78sqlite *sqlite_open(const char *filename, int mode, char **errmsg); 79 80/* 81** A function to close the database. 82** 83** Call this function with a pointer to a structure that was previously 84** returned from sqlite_open() and the corresponding database will by closed. 85*/ 86void sqlite_close(sqlite *); 87 88/* 89** The type for a callback function. 90*/ 91typedef int (*sqlite_callback)(void*,int,char**, char**); 92 93/* 94** A function to executes one or more statements of SQL. 95** 96** If one or more of the SQL statements are queries, then 97** the callback function specified by the 3rd parameter is 98** invoked once for each row of the query result. This callback 99** should normally return 0. If the callback returns a non-zero 100** value then the query is aborted, all subsequent SQL statements 101** are skipped and the sqlite_exec() function returns the SQLITE_ABORT. 102** 103** The 4th parameter is an arbitrary pointer that is passed 104** to the callback function as its first parameter. 105** 106** The 2nd parameter to the callback function is the number of 107** columns in the query result. The 3rd parameter to the callback 108** is an array of strings holding the values for each column. 109** The 4th parameter to the callback is an array of strings holding 110** the names of each column. 111** 112** The callback function may be NULL, even for queries. A NULL 113** callback is not an error. It just means that no callback 114** will be invoked. 115** 116** If an error occurs while parsing or evaluating the SQL (but 117** not while executing the callback) then an appropriate error 118** message is written into memory obtained from malloc() and 119** *errmsg is made to point to that message. The calling function 120** is responsible for freeing the memory that holds the error 121** message. Use sqlite_freemem() for this. If errmsg==NULL, 122** then no error message is ever written. 123** 124** The return value is is SQLITE_OK if there are no errors and 125** some other return code if there is an error. The particular 126** return value depends on the type of error. 127** 128** If the query could not be executed because a database file is 129** locked or busy, then this function returns SQLITE_BUSY. (This 130** behavior can be modified somewhat using the sqlite_busy_handler() 131** and sqlite_busy_timeout() functions below.) 132*/ 133int sqlite_exec( 134 sqlite*, /* An open database */ 135 const char *sql, /* SQL to be executed */ 136 sqlite_callback, /* Callback function */ 137 void *, /* 1st argument to callback function */ 138 char **errmsg /* Error msg written here */ 139); 140 141/* 142** Return values for sqlite_exec() and sqlite_step() 143*/ 144#define SQLITE_OK 0 /* Successful result */ 145#define SQLITE_ERROR 1 /* SQL error or missing database */ 146#define SQLITE_INTERNAL 2 /* An internal logic error in SQLite */ 147#define SQLITE_PERM 3 /* Access permission denied */ 148#define SQLITE_ABORT 4 /* Callback routine requested an abort */ 149#define SQLITE_BUSY 5 /* The database file is locked */ 150#define SQLITE_LOCKED 6 /* A table in the database is locked */ 151#define SQLITE_NOMEM 7 /* A malloc() failed */ 152#define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 153#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite_interrupt() */ 154#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 155#define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 156#define SQLITE_NOTFOUND 12 /* (Internal Only) Table or record not found */ 157#define SQLITE_FULL 13 /* Insertion failed because database is full */ 158#define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 159#define SQLITE_PROTOCOL 15 /* Database lock protocol error */ 160#define SQLITE_EMPTY 16 /* (Internal Only) Database table is empty */ 161#define SQLITE_SCHEMA 17 /* The database schema changed */ 162#define SQLITE_TOOBIG 18 /* Too much data for one row of a table */ 163#define SQLITE_CONSTRAINT 19 /* Abort due to contraint violation */ 164#define SQLITE_MISMATCH 20 /* Data type mismatch */ 165#define SQLITE_MISUSE 21 /* Library used incorrectly */ 166#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 167#define SQLITE_AUTH 23 /* Authorization denied */ 168#define SQLITE_FORMAT 24 /* Auxiliary database format error */ 169#define SQLITE_RANGE 25 /* 2nd parameter to sqlite_bind out of range */ 170#define SQLITE_NOTADB 26 /* File opened that is not a database file */ 171#define SQLITE_ROW 100 /* sqlite_step() has another row ready */ 172#define SQLITE_DONE 101 /* sqlite_step() has finished executing */ 173 174/* 175** Each entry in an SQLite table has a unique integer key. (The key is 176** the value of the INTEGER PRIMARY KEY column if there is such a column, 177** otherwise the key is generated at random. The unique key is always 178** available as the ROWID, OID, or _ROWID_ column.) The following routine 179** returns the integer key of the most recent insert in the database. 180** 181** This function is similar to the mysql_insert_id() function from MySQL. 182*/ 183int sqlite_last_insert_rowid(sqlite*); 184 185/* 186** This function returns the number of database rows that were changed 187** (or inserted or deleted) by the most recent called sqlite_exec(). 188** 189** All changes are counted, even if they were later undone by a 190** ROLLBACK or ABORT. Except, changes associated with creating and 191** dropping tables are not counted. 192** 193** If a callback invokes sqlite_exec() recursively, then the changes 194** in the inner, recursive call are counted together with the changes 195** in the outer call. 196** 197** SQLite implements the command "DELETE FROM table" without a WHERE clause 198** by dropping and recreating the table. (This is much faster than going 199** through and deleting individual elements form the table.) Because of 200** this optimization, the change count for "DELETE FROM table" will be 201** zero regardless of the number of elements that were originally in the 202** table. To get an accurate count of the number of rows deleted, use 203** "DELETE FROM table WHERE 1" instead. 204*/ 205int sqlite_changes(sqlite*); 206 207/* 208** This function returns the number of database rows that were changed 209** by the last INSERT, UPDATE, or DELETE statment executed by sqlite_exec(), 210** or by the last VM to run to completion. The change count is not updated 211** by SQL statements other than INSERT, UPDATE or DELETE. 212** 213** Changes are counted, even if they are later undone by a ROLLBACK or 214** ABORT. Changes associated with trigger programs that execute as a 215** result of the INSERT, UPDATE, or DELETE statement are not counted. 216** 217** If a callback invokes sqlite_exec() recursively, then the changes 218** in the inner, recursive call are counted together with the changes 219** in the outer call. 220** 221** SQLite implements the command "DELETE FROM table" without a WHERE clause 222** by dropping and recreating the table. (This is much faster than going 223** through and deleting individual elements form the table.) Because of 224** this optimization, the change count for "DELETE FROM table" will be 225** zero regardless of the number of elements that were originally in the 226** table. To get an accurate count of the number of rows deleted, use 227** "DELETE FROM table WHERE 1" instead. 228** 229******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 230*/ 231int sqlite_last_statement_changes(sqlite*); 232 233/* If the parameter to this routine is one of the return value constants 234** defined above, then this routine returns a constant text string which 235** descripts (in English) the meaning of the return value. 236*/ 237const char *sqlite_error_string(int); 238#define sqliteErrStr sqlite_error_string /* Legacy. Do not use in new code. */ 239 240/* This function causes any pending database operation to abort and 241** return at its earliest opportunity. This routine is typically 242** called in response to a user action such as pressing "Cancel" 243** or Ctrl-C where the user wants a long query operation to halt 244** immediately. 245*/ 246void sqlite_interrupt(sqlite*); 247 248 249/* This function returns true if the given input string comprises 250** one or more complete SQL statements. 251** 252** The algorithm is simple. If the last token other than spaces 253** and comments is a semicolon, then return true. otherwise return 254** false. 255*/ 256int sqlite_complete(const char *sql); 257 258/* 259** This routine identifies a callback function that is invoked 260** whenever an attempt is made to open a database table that is 261** currently locked by another process or thread. If the busy callback 262** is NULL, then sqlite_exec() returns SQLITE_BUSY immediately if 263** it finds a locked table. If the busy callback is not NULL, then 264** sqlite_exec() invokes the callback with three arguments. The 265** second argument is the name of the locked table and the third 266** argument is the number of times the table has been busy. If the 267** busy callback returns 0, then sqlite_exec() immediately returns 268** SQLITE_BUSY. If the callback returns non-zero, then sqlite_exec() 269** tries to open the table again and the cycle repeats. 270** 271** The default busy callback is NULL. 272** 273** Sqlite is re-entrant, so the busy handler may start a new query. 274** (It is not clear why anyone would every want to do this, but it 275** is allowed, in theory.) But the busy handler may not close the 276** database. Closing the database from a busy handler will delete 277** data structures out from under the executing query and will 278** probably result in a coredump. 279*/ 280void sqlite_busy_handler(sqlite*, int(*)(void*,const char*,int), void*); 281 282/* 283** This routine sets a busy handler that sleeps for a while when a 284** table is locked. The handler will sleep multiple times until 285** at least "ms" milleseconds of sleeping have been done. After 286** "ms" milleseconds of sleeping, the handler returns 0 which 287** causes sqlite_exec() to return SQLITE_BUSY. 288** 289** Calling this routine with an argument less than or equal to zero 290** turns off all busy handlers. 291*/ 292void sqlite_busy_timeout(sqlite*, int ms); 293 294/* 295** This next routine is really just a wrapper around sqlite_exec(). 296** Instead of invoking a user-supplied callback for each row of the 297** result, this routine remembers each row of the result in memory 298** obtained from malloc(), then returns all of the result after the 299** query has finished. 300** 301** As an example, suppose the query result where this table: 302** 303** Name | Age 304** ----------------------- 305** Alice | 43 306** Bob | 28 307** Cindy | 21 308** 309** If the 3rd argument were &azResult then after the function returns 310** azResult will contain the following data: 311** 312** azResult[0] = "Name"; 313** azResult[1] = "Age"; 314** azResult[2] = "Alice"; 315** azResult[3] = "43"; 316** azResult[4] = "Bob"; 317** azResult[5] = "28"; 318** azResult[6] = "Cindy"; 319** azResult[7] = "21"; 320** 321** Notice that there is an extra row of data containing the column 322** headers. But the *nrow return value is still 3. *ncolumn is 323** set to 2. In general, the number of values inserted into azResult 324** will be ((*nrow) + 1)*(*ncolumn). 325** 326** After the calling function has finished using the result, it should 327** pass the result data pointer to sqlite_free_table() in order to 328** release the memory that was malloc-ed. Because of the way the 329** malloc() happens, the calling function must not try to call 330** malloc() directly. Only sqlite_free_table() is able to release 331** the memory properly and safely. 332** 333** The return value of this routine is the same as from sqlite_exec(). 334*/ 335int sqlite_get_table( 336 sqlite*, /* An open database */ 337 const char *sql, /* SQL to be executed */ 338 char ***resultp, /* Result written to a char *[] that this points to */ 339 int *nrow, /* Number of result rows written here */ 340 int *ncolumn, /* Number of result columns written here */ 341 char **errmsg /* Error msg written here */ 342); 343 344/* 345** Call this routine to free the memory that sqlite_get_table() allocated. 346*/ 347void sqlite_free_table(char **result); 348 349/* 350** The following routines are wrappers around sqlite_exec() and 351** sqlite_get_table(). The only difference between the routines that 352** follow and the originals is that the second argument to the 353** routines that follow is really a printf()-style format 354** string describing the SQL to be executed. Arguments to the format 355** string appear at the end of the argument list. 356** 357** All of the usual printf formatting options apply. In addition, there 358** is a "%q" option. %q works like %s in that it substitutes a null-terminated 359** string from the argument list. But %q also doubles every '\'' character. 360** %q is designed for use inside a string literal. By doubling each '\'' 361** character it escapes that character and allows it to be inserted into 362** the string. 363** 364** For example, so some string variable contains text as follows: 365** 366** char *zText = "It's a happy day!"; 367** 368** We can use this text in an SQL statement as follows: 369** 370** sqlite_exec_printf(db, "INSERT INTO table VALUES('%q')", 371** callback1, 0, 0, zText); 372** 373** Because the %q format string is used, the '\'' character in zText 374** is escaped and the SQL generated is as follows: 375** 376** INSERT INTO table1 VALUES('It''s a happy day!') 377** 378** This is correct. Had we used %s instead of %q, the generated SQL 379** would have looked like this: 380** 381** INSERT INTO table1 VALUES('It's a happy day!'); 382** 383** This second example is an SQL syntax error. As a general rule you 384** should always use %q instead of %s when inserting text into a string 385** literal. 386*/ 387int sqlite_exec_printf( 388 sqlite*, /* An open database */ 389 const char *sqlFormat, /* printf-style format string for the SQL */ 390 sqlite_callback, /* Callback function */ 391 void *, /* 1st argument to callback function */ 392 char **errmsg, /* Error msg written here */ 393 ... /* Arguments to the format string. */ 394); 395int sqlite_exec_vprintf( 396 sqlite*, /* An open database */ 397 const char *sqlFormat, /* printf-style format string for the SQL */ 398 sqlite_callback, /* Callback function */ 399 void *, /* 1st argument to callback function */ 400 char **errmsg, /* Error msg written here */ 401 va_list ap /* Arguments to the format string. */ 402); 403int sqlite_get_table_printf( 404 sqlite*, /* An open database */ 405 const char *sqlFormat, /* printf-style format string for the SQL */ 406 char ***resultp, /* Result written to a char *[] that this points to */ 407 int *nrow, /* Number of result rows written here */ 408 int *ncolumn, /* Number of result columns written here */ 409 char **errmsg, /* Error msg written here */ 410 ... /* Arguments to the format string */ 411); 412int sqlite_get_table_vprintf( 413 sqlite*, /* An open database */ 414 const char *sqlFormat, /* printf-style format string for the SQL */ 415 char ***resultp, /* Result written to a char *[] that this points to */ 416 int *nrow, /* Number of result rows written here */ 417 int *ncolumn, /* Number of result columns written here */ 418 char **errmsg, /* Error msg written here */ 419 va_list ap /* Arguments to the format string */ 420); 421char *sqlite_mprintf(const char*,...); 422char *sqlite_vmprintf(const char*, va_list); 423 424/* 425** Windows systems should call this routine to free memory that 426** is returned in the in the errmsg parameter of sqlite_open() when 427** SQLite is a DLL. For some reason, it does not work to call free() 428** directly. 429*/ 430void sqlite_freemem(void *p); 431 432/* 433** Windows systems need functions to call to return the sqlite_version 434** and sqlite_encoding strings. 435*/ 436const char *sqlite_libversion(void); 437const char *sqlite_libencoding(void); 438 439/* 440** A pointer to the following structure is used to communicate with 441** the implementations of user-defined functions. 442*/ 443typedef struct sqlite_func sqlite_func; 444 445/* 446** Use the following routines to create new user-defined functions. See 447** the documentation for details. 448*/ 449int sqlite_create_function( 450 sqlite*, /* Database where the new function is registered */ 451 const char *zName, /* Name of the new function */ 452 int nArg, /* Number of arguments. -1 means any number */ 453 void (*xFunc)(sqlite_func*,int,const char**), /* C code to implement */ 454 void *pUserData /* Available via the sqlite_user_data() call */ 455); 456int sqlite_create_aggregate( 457 sqlite*, /* Database where the new function is registered */ 458 const char *zName, /* Name of the function */ 459 int nArg, /* Number of arguments */ 460 void (*xStep)(sqlite_func*,int,const char**), /* Called for each row */ 461 void (*xFinalize)(sqlite_func*), /* Called once to get final result */ 462 void *pUserData /* Available via the sqlite_user_data() call */ 463); 464 465/* 466** Use the following routine to define the datatype returned by a 467** user-defined function. The second argument can be one of the 468** constants SQLITE_NUMERIC, SQLITE_TEXT, or SQLITE_ARGS or it 469** can be an integer greater than or equal to zero. When the datatype 470** parameter is non-negative, the type of the result will be the 471** same as the datatype-th argument. If datatype==SQLITE_NUMERIC 472** then the result is always numeric. If datatype==SQLITE_TEXT then 473** the result is always text. If datatype==SQLITE_ARGS then the result 474** is numeric if any argument is numeric and is text otherwise. 475*/ 476int sqlite_function_type( 477 sqlite *db, /* The database there the function is registered */ 478 const char *zName, /* Name of the function */ 479 int datatype /* The datatype for this function */ 480); 481#define SQLITE_NUMERIC (-1) 482#define SQLITE_TEXT (-2) 483#define SQLITE_ARGS (-3) 484 485/* 486** The user function implementations call one of the following four routines 487** in order to return their results. The first parameter to each of these 488** routines is a copy of the first argument to xFunc() or xFinialize(). 489** The second parameter to these routines is the result to be returned. 490** A NULL can be passed as the second parameter to sqlite_set_result_string() 491** in order to return a NULL result. 492** 493** The 3rd argument to _string and _error is the number of characters to 494** take from the string. If this argument is negative, then all characters 495** up to and including the first '\000' are used. 496** 497** The sqlite_set_result_string() function allocates a buffer to hold the 498** result and returns a pointer to this buffer. The calling routine 499** (that is, the implmentation of a user function) can alter the content 500** of this buffer if desired. 501*/ 502char *sqlite_set_result_string(sqlite_func*,const char*,int); 503void sqlite_set_result_int(sqlite_func*,int); 504void sqlite_set_result_double(sqlite_func*,double); 505void sqlite_set_result_error(sqlite_func*,const char*,int); 506 507/* 508** The pUserData parameter to the sqlite_create_function() and 509** sqlite_create_aggregate() routines used to register user functions 510** is available to the implementation of the function using this 511** call. 512*/ 513void *sqlite_user_data(sqlite_func*); 514 515/* 516** Aggregate functions use the following routine to allocate 517** a structure for storing their state. The first time this routine 518** is called for a particular aggregate, a new structure of size nBytes 519** is allocated, zeroed, and returned. On subsequent calls (for the 520** same aggregate instance) the same buffer is returned. The implementation 521** of the aggregate can use the returned buffer to accumulate data. 522** 523** The buffer allocated is freed automatically be SQLite. 524*/ 525void *sqlite_aggregate_context(sqlite_func*, int nBytes); 526 527/* 528** The next routine returns the number of calls to xStep for a particular 529** aggregate function instance. The current call to xStep counts so this 530** routine always returns at least 1. 531*/ 532int sqlite_aggregate_count(sqlite_func*); 533 534/* 535** This routine registers a callback with the SQLite library. The 536** callback is invoked (at compile-time, not at run-time) for each 537** attempt to access a column of a table in the database. The callback 538** returns SQLITE_OK if access is allowed, SQLITE_DENY if the entire 539** SQL statement should be aborted with an error and SQLITE_IGNORE 540** if the column should be treated as a NULL value. 541*/ 542int sqlite_set_authorizer( 543 sqlite*, 544 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 545 void *pUserData 546); 547 548/* 549** The second parameter to the access authorization function above will 550** be one of the values below. These values signify what kind of operation 551** is to be authorized. The 3rd and 4th parameters to the authorization 552** function will be parameters or NULL depending on which of the following 553** codes is used as the second parameter. The 5th parameter is the name 554** of the database ("main", "temp", etc.) if applicable. The 6th parameter 555** is the name of the inner-most trigger or view that is responsible for 556** the access attempt or NULL if this access attempt is directly from 557** input SQL code. 558** 559** Arg-3 Arg-4 560*/ 561#define SQLITE_COPY 0 /* Table Name File Name */ 562#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 563#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 564#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 565#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 566#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 567#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 568#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 569#define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 570#define SQLITE_DELETE 9 /* Table Name NULL */ 571#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 572#define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 573#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 574#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 575#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 576#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 577#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 578#define SQLITE_DROP_VIEW 17 /* View Name NULL */ 579#define SQLITE_INSERT 18 /* Table Name NULL */ 580#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 581#define SQLITE_READ 20 /* Table Name Column Name */ 582#define SQLITE_SELECT 21 /* NULL NULL */ 583#define SQLITE_TRANSACTION 22 /* NULL NULL */ 584#define SQLITE_UPDATE 23 /* Table Name Column Name */ 585#define SQLITE_ATTACH 24 /* Filename NULL */ 586#define SQLITE_DETACH 25 /* Database Name NULL */ 587 588 589/* 590** The return value of the authorization function should be one of the 591** following constants: 592*/ 593/* #define SQLITE_OK 0 // Allow access (This is actually defined above) */ 594#define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 595#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 596 597/* 598** Register a function that is called at every invocation of sqlite_exec() 599** or sqlite_compile(). This function can be used (for example) to generate 600** a log file of all SQL executed against a database. 601*/ 602void *sqlite_trace(sqlite*, void(*xTrace)(void*,const char*), void*); 603 604/*** The Callback-Free API 605** 606** The following routines implement a new way to access SQLite that does not 607** involve the use of callbacks. 608** 609** An sqlite_vm is an opaque object that represents a single SQL statement 610** that is ready to be executed. 611*/ 612typedef struct sqlite_vm sqlite_vm; 613 614/* 615** To execute an SQLite query without the use of callbacks, you first have 616** to compile the SQL using this routine. The 1st parameter "db" is a pointer 617** to an sqlite object obtained from sqlite_open(). The 2nd parameter 618** "zSql" is the text of the SQL to be compiled. The remaining parameters 619** are all outputs. 620** 621** *pzTail is made to point to the first character past the end of the first 622** SQL statement in zSql. This routine only compiles the first statement 623** in zSql, so *pzTail is left pointing to what remains uncompiled. 624** 625** *ppVm is left pointing to a "virtual machine" that can be used to execute 626** the compiled statement. Or if there is an error, *ppVm may be set to NULL. 627** If the input text contained no SQL (if the input is and empty string or 628** a comment) then *ppVm is set to NULL. 629** 630** If any errors are detected during compilation, an error message is written 631** into space obtained from malloc() and *pzErrMsg is made to point to that 632** error message. The calling routine is responsible for freeing the text 633** of this message when it has finished with it. Use sqlite_freemem() to 634** free the message. pzErrMsg may be NULL in which case no error message 635** will be generated. 636** 637** On success, SQLITE_OK is returned. Otherwise and error code is returned. 638*/ 639int sqlite_compile( 640 sqlite *db, /* The open database */ 641 const char *zSql, /* SQL statement to be compiled */ 642 const char **pzTail, /* OUT: uncompiled tail of zSql */ 643 sqlite_vm **ppVm, /* OUT: the virtual machine to execute zSql */ 644 char **pzErrmsg /* OUT: Error message. */ 645); 646 647/* 648** After an SQL statement has been compiled, it is handed to this routine 649** to be executed. This routine executes the statement as far as it can 650** go then returns. The return value will be one of SQLITE_DONE, 651** SQLITE_ERROR, SQLITE_BUSY, SQLITE_ROW, or SQLITE_MISUSE. 652** 653** SQLITE_DONE means that the execute of the SQL statement is complete 654** an no errors have occurred. sqlite_step() should not be called again 655** for the same virtual machine. *pN is set to the number of columns in 656** the result set and *pazColName is set to an array of strings that 657** describe the column names and datatypes. The name of the i-th column 658** is (*pazColName)[i] and the datatype of the i-th column is 659** (*pazColName)[i+*pN]. *pazValue is set to NULL. 660** 661** SQLITE_ERROR means that the virtual machine encountered a run-time 662** error. sqlite_step() should not be called again for the same 663** virtual machine. *pN is set to 0 and *pazColName and *pazValue are set 664** to NULL. Use sqlite_finalize() to obtain the specific error code 665** and the error message text for the error. 666** 667** SQLITE_BUSY means that an attempt to open the database failed because 668** another thread or process is holding a lock. The calling routine 669** can try again to open the database by calling sqlite_step() again. 670** The return code will only be SQLITE_BUSY if no busy handler is registered 671** using the sqlite_busy_handler() or sqlite_busy_timeout() routines. If 672** a busy handler callback has been registered but returns 0, then this 673** routine will return SQLITE_ERROR and sqltie_finalize() will return 674** SQLITE_BUSY when it is called. 675** 676** SQLITE_ROW means that a single row of the result is now available. 677** The data is contained in *pazValue. The value of the i-th column is 678** (*azValue)[i]. *pN and *pazColName are set as described in SQLITE_DONE. 679** Invoke sqlite_step() again to advance to the next row. 680** 681** SQLITE_MISUSE is returned if sqlite_step() is called incorrectly. 682** For example, if you call sqlite_step() after the virtual machine 683** has halted (after a prior call to sqlite_step() has returned SQLITE_DONE) 684** or if you call sqlite_step() with an incorrectly initialized virtual 685** machine or a virtual machine that has been deleted or that is associated 686** with an sqlite structure that has been closed. 687*/ 688int sqlite_step( 689 sqlite_vm *pVm, /* The virtual machine to execute */ 690 int *pN, /* OUT: Number of columns in result */ 691 const char ***pazValue, /* OUT: Column data */ 692 const char ***pazColName /* OUT: Column names and datatypes */ 693); 694 695/* 696** This routine is called to delete a virtual machine after it has finished 697** executing. The return value is the result code. SQLITE_OK is returned 698** if the statement executed successfully and some other value is returned if 699** there was any kind of error. If an error occurred and pzErrMsg is not 700** NULL, then an error message is written into memory obtained from malloc() 701** and *pzErrMsg is made to point to that error message. The calling routine 702** should use sqlite_freemem() to delete this message when it has finished 703** with it. 704** 705** This routine can be called at any point during the execution of the 706** virtual machine. If the virtual machine has not completed execution 707** when this routine is called, that is like encountering an error or 708** an interrupt. (See sqlite_interrupt().) Incomplete updates may be 709** rolled back and transactions cancelled, depending on the circumstances, 710** and the result code returned will be SQLITE_ABORT. 711*/ 712int sqlite_finalize(sqlite_vm*, char **pzErrMsg); 713 714/* 715** This routine deletes the virtual machine, writes any error message to 716** *pzErrMsg and returns an SQLite return code in the same way as the 717** sqlite_finalize() function. 718** 719** Additionally, if ppVm is not NULL, *ppVm is left pointing to a new virtual 720** machine loaded with the compiled version of the original query ready for 721** execution. 722** 723** If sqlite_reset() returns SQLITE_SCHEMA, then *ppVm is set to NULL. 724** 725******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 726*/ 727int sqlite_reset(sqlite_vm*, char **pzErrMsg); 728 729/* 730** If the SQL that was handed to sqlite_compile contains variables that 731** are represeted in the SQL text by a question mark ('?'). This routine 732** is used to assign values to those variables. 733** 734** The first parameter is a virtual machine obtained from sqlite_compile(). 735** The 2nd "idx" parameter determines which variable in the SQL statement 736** to bind the value to. The left most '?' is 1. The 3rd parameter is 737** the value to assign to that variable. The 4th parameter is the number 738** of bytes in the value, including the terminating \000 for strings. 739** Finally, the 5th "copy" parameter is TRUE if SQLite should make its 740** own private copy of this value, or false if the space that the 3rd 741** parameter points to will be unchanging and can be used directly by 742** SQLite. 743** 744** Unbound variables are treated as having a value of NULL. To explicitly 745** set a variable to NULL, call this routine with the 3rd parameter as a 746** NULL pointer. 747** 748** If the 4th "len" parameter is -1, then strlen() is used to find the 749** length. 750** 751** This routine can only be called immediately after sqlite_compile() 752** or sqlite_reset() and before any calls to sqlite_step(). 753** 754******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 755*/ 756int sqlite_bind(sqlite_vm*, int idx, const char *value, int len, int copy); 757 758/* 759** This routine configures a callback function - the progress callback - that 760** is invoked periodically during long running calls to sqlite_exec(), 761** sqlite_step() and sqlite_get_table(). An example use for this API is to keep 762** a GUI updated during a large query. 763** 764** The progress callback is invoked once for every N virtual machine opcodes, 765** where N is the second argument to this function. The progress callback 766** itself is identified by the third argument to this function. The fourth 767** argument to this function is a void pointer passed to the progress callback 768** function each time it is invoked. 769** 770** If a call to sqlite_exec(), sqlite_step() or sqlite_get_table() results 771** in less than N opcodes being executed, then the progress callback is not 772** invoked. 773** 774** Calling this routine overwrites any previously installed progress callback. 775** To remove the progress callback altogether, pass NULL as the third 776** argument to this function. 777** 778** If the progress callback returns a result other than 0, then the current 779** query is immediately terminated and any database changes rolled back. If the 780** query was part of a larger transaction, then the transaction is not rolled 781** back and remains active. The sqlite_exec() call returns SQLITE_ABORT. 782** 783******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 784*/ 785void sqlite_progress_handler(sqlite*, int, int(*)(void*), void*); 786 787/* 788** Register a callback function to be invoked whenever a new transaction 789** is committed. The pArg argument is passed through to the callback. 790** callback. If the callback function returns non-zero, then the commit 791** is converted into a rollback. 792** 793** If another function was previously registered, its pArg value is returned. 794** Otherwise NULL is returned. 795** 796** Registering a NULL function disables the callback. 797** 798******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 799*/ 800void *sqlite_commit_hook(sqlite*, int(*)(void*), void*); 801 802/* 803** Open an encrypted SQLite database. If pKey==0 or nKey==0, this routine 804** is the same as sqlite_open(). 805** 806** The code to implement this API is not available in the public release 807** of SQLite. 808*/ 809sqlite *sqlite_open_encrypted( 810 const char *zFilename, /* Name of the encrypted database */ 811 const void *pKey, /* Pointer to the key */ 812 int nKey, /* Number of bytes in the key */ 813 int *pErrcode, /* Write error code here */ 814 char **pzErrmsg /* Write error message here */ 815); 816 817/* 818** Change the key on an open database. If the current database is not 819** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the 820** database is decrypted. 821** 822** The code to implement this API is not available in the public release 823** of SQLite. 824*/ 825int sqlite_rekey( 826 sqlite *db, /* Database to be rekeyed */ 827 const void *pKey, int nKey /* The new key */ 828); 829 830/* 831** Encode a binary buffer "in" of size n bytes so that it contains 832** no instances of characters '\'' or '\000'. The output is 833** null-terminated and can be used as a string value in an INSERT 834** or UPDATE statement. Use sqlite_decode_binary() to convert the 835** string back into its original binary. 836** 837** The result is written into a preallocated output buffer "out". 838** "out" must be able to hold at least 2 +(257*n)/254 bytes. 839** In other words, the output will be expanded by as much as 3 840** bytes for every 254 bytes of input plus 2 bytes of fixed overhead. 841** (This is approximately 2 + 1.0118*n or about a 1.2% size increase.) 842** 843** The return value is the number of characters in the encoded 844** string, excluding the "\000" terminator. 845** 846** If out==NULL then no output is generated but the routine still returns 847** the number of characters that would have been generated if out had 848** not been NULL. 849*/ 850int sqlite_encode_binary(const unsigned char *in, int n, unsigned char *out); 851 852/* 853** Decode the string "in" into binary data and write it into "out". 854** This routine reverses the encoding created by sqlite_encode_binary(). 855** The output will always be a few bytes less than the input. The number 856** of bytes of output is returned. If the input is not a well-formed 857** encoding, -1 is returned. 858** 859** The "in" and "out" parameters may point to the same buffer in order 860** to decode a string in place. 861*/ 862int sqlite_decode_binary(const unsigned char *in, unsigned char *out); 863 864#ifdef __cplusplus 865} /* End of the 'extern "C"' block */ 866#endif 867 868#endif /* _SQLITE_H_ */ 869