1 2#pragma ident "%Z%%M% %I% %E% SMI" 3 4/* 5** 2001 September 15 6** 7** The author disclaims copyright to this source code. In place of 8** a legal notice, here is a blessing: 9** 10** May you do good and not evil. 11** May you find forgiveness for yourself and forgive others. 12** May you share freely, never taking more than you give. 13** 14************************************************************************* 15** This header file defines the interface that the SQLite library 16** presents to client programs. 17** 18** @(#) $Id: sqlite.h.in,v 1.60 2004/03/14 22:12:35 drh Exp $ 19*/ 20#ifndef _SQLITE_H_ 21#define _SQLITE_H_ 22#include <stdarg.h> /* Needed for the definition of va_list */ 23 24/* 25** Make sure we can call this stuff from C++. 26*/ 27#ifdef __cplusplus 28extern "C" { 29#endif 30 31/* 32** The version of the SQLite library. 33*/ 34#define SQLITE_VERSION "--VERS--" 35 36/* 37** The version string is also compiled into the library so that a program 38** can check to make sure that the lib*.a file and the *.h file are from 39** the same version. 40*/ 41extern const char sqlite_version[]; 42 43/* 44** The SQLITE_UTF8 macro is defined if the library expects to see 45** UTF-8 encoded data. The SQLITE_ISO8859 macro is defined if the 46** iso8859 encoded should be used. 47*/ 48#define SQLITE_--ENCODING-- 1 49 50/* 51** The following constant holds one of two strings, "UTF-8" or "iso8859", 52** depending on which character encoding the SQLite library expects to 53** see. The character encoding makes a difference for the LIKE and GLOB 54** operators and for the LENGTH() and SUBSTR() functions. 55*/ 56extern const char sqlite_encoding[]; 57 58/* 59** Each open sqlite database is represented by an instance of the 60** following opaque structure. 61*/ 62typedef struct sqlite sqlite; 63 64/* 65** A function to open a new sqlite database. 66** 67** If the database does not exist and mode indicates write 68** permission, then a new database is created. If the database 69** does not exist and mode does not indicate write permission, 70** then the open fails, an error message generated (if errmsg!=0) 71** and the function returns 0. 72** 73** If mode does not indicates user write permission, then the 74** database is opened read-only. 75** 76** The Truth: As currently implemented, all databases are opened 77** for writing all the time. Maybe someday we will provide the 78** ability to open a database readonly. The mode parameters is 79** provided in anticipation of that enhancement. 80*/ 81sqlite *sqlite_open(const char *filename, int mode, char **errmsg); 82 83/* 84** A function to close the database. 85** 86** Call this function with a pointer to a structure that was previously 87** returned from sqlite_open() and the corresponding database will by closed. 88*/ 89void sqlite_close(sqlite *); 90 91/* 92** The type for a callback function. 93*/ 94typedef int (*sqlite_callback)(void*,int,char**, char**); 95 96/* 97** A function to executes one or more statements of SQL. 98** 99** If one or more of the SQL statements are queries, then 100** the callback function specified by the 3rd parameter is 101** invoked once for each row of the query result. This callback 102** should normally return 0. If the callback returns a non-zero 103** value then the query is aborted, all subsequent SQL statements 104** are skipped and the sqlite_exec() function returns the SQLITE_ABORT. 105** 106** The 4th parameter is an arbitrary pointer that is passed 107** to the callback function as its first parameter. 108** 109** The 2nd parameter to the callback function is the number of 110** columns in the query result. The 3rd parameter to the callback 111** is an array of strings holding the values for each column. 112** The 4th parameter to the callback is an array of strings holding 113** the names of each column. 114** 115** The callback function may be NULL, even for queries. A NULL 116** callback is not an error. It just means that no callback 117** will be invoked. 118** 119** If an error occurs while parsing or evaluating the SQL (but 120** not while executing the callback) then an appropriate error 121** message is written into memory obtained from malloc() and 122** *errmsg is made to point to that message. The calling function 123** is responsible for freeing the memory that holds the error 124** message. Use sqlite_freemem() for this. If errmsg==NULL, 125** then no error message is ever written. 126** 127** The return value is is SQLITE_OK if there are no errors and 128** some other return code if there is an error. The particular 129** return value depends on the type of error. 130** 131** If the query could not be executed because a database file is 132** locked or busy, then this function returns SQLITE_BUSY. (This 133** behavior can be modified somewhat using the sqlite_busy_handler() 134** and sqlite_busy_timeout() functions below.) 135*/ 136int sqlite_exec( 137 sqlite*, /* An open database */ 138 const char *sql, /* SQL to be executed */ 139 sqlite_callback, /* Callback function */ 140 void *, /* 1st argument to callback function */ 141 char **errmsg /* Error msg written here */ 142); 143 144/* 145** Return values for sqlite_exec() and sqlite_step() 146*/ 147#define SQLITE_OK 0 /* Successful result */ 148#define SQLITE_ERROR 1 /* SQL error or missing database */ 149#define SQLITE_INTERNAL 2 /* An internal logic error in SQLite */ 150#define SQLITE_PERM 3 /* Access permission denied */ 151#define SQLITE_ABORT 4 /* Callback routine requested an abort */ 152#define SQLITE_BUSY 5 /* The database file is locked */ 153#define SQLITE_LOCKED 6 /* A table in the database is locked */ 154#define SQLITE_NOMEM 7 /* A malloc() failed */ 155#define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 156#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite_interrupt() */ 157#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 158#define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 159#define SQLITE_NOTFOUND 12 /* (Internal Only) Table or record not found */ 160#define SQLITE_FULL 13 /* Insertion failed because database is full */ 161#define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 162#define SQLITE_PROTOCOL 15 /* Database lock protocol error */ 163#define SQLITE_EMPTY 16 /* (Internal Only) Database table is empty */ 164#define SQLITE_SCHEMA 17 /* The database schema changed */ 165#define SQLITE_TOOBIG 18 /* Too much data for one row of a table */ 166#define SQLITE_CONSTRAINT 19 /* Abort due to contraint violation */ 167#define SQLITE_MISMATCH 20 /* Data type mismatch */ 168#define SQLITE_MISUSE 21 /* Library used incorrectly */ 169#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 170#define SQLITE_AUTH 23 /* Authorization denied */ 171#define SQLITE_FORMAT 24 /* Auxiliary database format error */ 172#define SQLITE_RANGE 25 /* 2nd parameter to sqlite_bind out of range */ 173#define SQLITE_NOTADB 26 /* File opened that is not a database file */ 174#define SQLITE_ROW 100 /* sqlite_step() has another row ready */ 175#define SQLITE_DONE 101 /* sqlite_step() has finished executing */ 176 177/* 178** Each entry in an SQLite table has a unique integer key. (The key is 179** the value of the INTEGER PRIMARY KEY column if there is such a column, 180** otherwise the key is generated at random. The unique key is always 181** available as the ROWID, OID, or _ROWID_ column.) The following routine 182** returns the integer key of the most recent insert in the database. 183** 184** This function is similar to the mysql_insert_id() function from MySQL. 185*/ 186int sqlite_last_insert_rowid(sqlite*); 187 188/* 189** This function returns the number of database rows that were changed 190** (or inserted or deleted) by the most recent called sqlite_exec(). 191** 192** All changes are counted, even if they were later undone by a 193** ROLLBACK or ABORT. Except, changes associated with creating and 194** dropping tables are not counted. 195** 196** If a callback invokes sqlite_exec() recursively, then the changes 197** in the inner, recursive call are counted together with the changes 198** in the outer call. 199** 200** SQLite implements the command "DELETE FROM table" without a WHERE clause 201** by dropping and recreating the table. (This is much faster than going 202** through and deleting individual elements form the table.) Because of 203** this optimization, the change count for "DELETE FROM table" will be 204** zero regardless of the number of elements that were originally in the 205** table. To get an accurate count of the number of rows deleted, use 206** "DELETE FROM table WHERE 1" instead. 207*/ 208int sqlite_changes(sqlite*); 209 210/* 211** This function returns the number of database rows that were changed 212** by the last INSERT, UPDATE, or DELETE statment executed by sqlite_exec(), 213** or by the last VM to run to completion. The change count is not updated 214** by SQL statements other than INSERT, UPDATE or DELETE. 215** 216** Changes are counted, even if they are later undone by a ROLLBACK or 217** ABORT. Changes associated with trigger programs that execute as a 218** result of the INSERT, UPDATE, or DELETE statement are not counted. 219** 220** If a callback invokes sqlite_exec() recursively, then the changes 221** in the inner, recursive call are counted together with the changes 222** in the outer call. 223** 224** SQLite implements the command "DELETE FROM table" without a WHERE clause 225** by dropping and recreating the table. (This is much faster than going 226** through and deleting individual elements form the table.) Because of 227** this optimization, the change count for "DELETE FROM table" will be 228** zero regardless of the number of elements that were originally in the 229** table. To get an accurate count of the number of rows deleted, use 230** "DELETE FROM table WHERE 1" instead. 231** 232******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 233*/ 234int sqlite_last_statement_changes(sqlite*); 235 236/* If the parameter to this routine is one of the return value constants 237** defined above, then this routine returns a constant text string which 238** descripts (in English) the meaning of the return value. 239*/ 240const char *sqlite_error_string(int); 241#define sqliteErrStr sqlite_error_string /* Legacy. Do not use in new code. */ 242 243/* This function causes any pending database operation to abort and 244** return at its earliest opportunity. This routine is typically 245** called in response to a user action such as pressing "Cancel" 246** or Ctrl-C where the user wants a long query operation to halt 247** immediately. 248*/ 249void sqlite_interrupt(sqlite*); 250 251 252/* This function returns true if the given input string comprises 253** one or more complete SQL statements. 254** 255** The algorithm is simple. If the last token other than spaces 256** and comments is a semicolon, then return true. otherwise return 257** false. 258*/ 259int sqlite_complete(const char *sql); 260 261/* 262** This routine identifies a callback function that is invoked 263** whenever an attempt is made to open a database table that is 264** currently locked by another process or thread. If the busy callback 265** is NULL, then sqlite_exec() returns SQLITE_BUSY immediately if 266** it finds a locked table. If the busy callback is not NULL, then 267** sqlite_exec() invokes the callback with three arguments. The 268** second argument is the name of the locked table and the third 269** argument is the number of times the table has been busy. If the 270** busy callback returns 0, then sqlite_exec() immediately returns 271** SQLITE_BUSY. If the callback returns non-zero, then sqlite_exec() 272** tries to open the table again and the cycle repeats. 273** 274** The default busy callback is NULL. 275** 276** Sqlite is re-entrant, so the busy handler may start a new query. 277** (It is not clear why anyone would every want to do this, but it 278** is allowed, in theory.) But the busy handler may not close the 279** database. Closing the database from a busy handler will delete 280** data structures out from under the executing query and will 281** probably result in a coredump. 282*/ 283void sqlite_busy_handler(sqlite*, int(*)(void*,const char*,int), void*); 284 285/* 286** This routine sets a busy handler that sleeps for a while when a 287** table is locked. The handler will sleep multiple times until 288** at least "ms" milleseconds of sleeping have been done. After 289** "ms" milleseconds of sleeping, the handler returns 0 which 290** causes sqlite_exec() to return SQLITE_BUSY. 291** 292** Calling this routine with an argument less than or equal to zero 293** turns off all busy handlers. 294*/ 295void sqlite_busy_timeout(sqlite*, int ms); 296 297/* 298** This next routine is really just a wrapper around sqlite_exec(). 299** Instead of invoking a user-supplied callback for each row of the 300** result, this routine remembers each row of the result in memory 301** obtained from malloc(), then returns all of the result after the 302** query has finished. 303** 304** As an example, suppose the query result where this table: 305** 306** Name | Age 307** ----------------------- 308** Alice | 43 309** Bob | 28 310** Cindy | 21 311** 312** If the 3rd argument were &azResult then after the function returns 313** azResult will contain the following data: 314** 315** azResult[0] = "Name"; 316** azResult[1] = "Age"; 317** azResult[2] = "Alice"; 318** azResult[3] = "43"; 319** azResult[4] = "Bob"; 320** azResult[5] = "28"; 321** azResult[6] = "Cindy"; 322** azResult[7] = "21"; 323** 324** Notice that there is an extra row of data containing the column 325** headers. But the *nrow return value is still 3. *ncolumn is 326** set to 2. In general, the number of values inserted into azResult 327** will be ((*nrow) + 1)*(*ncolumn). 328** 329** After the calling function has finished using the result, it should 330** pass the result data pointer to sqlite_free_table() in order to 331** release the memory that was malloc-ed. Because of the way the 332** malloc() happens, the calling function must not try to call 333** malloc() directly. Only sqlite_free_table() is able to release 334** the memory properly and safely. 335** 336** The return value of this routine is the same as from sqlite_exec(). 337*/ 338int sqlite_get_table( 339 sqlite*, /* An open database */ 340 const char *sql, /* SQL to be executed */ 341 char ***resultp, /* Result written to a char *[] that this points to */ 342 int *nrow, /* Number of result rows written here */ 343 int *ncolumn, /* Number of result columns written here */ 344 char **errmsg /* Error msg written here */ 345); 346 347/* 348** Call this routine to free the memory that sqlite_get_table() allocated. 349*/ 350void sqlite_free_table(char **result); 351 352/* 353** The following routines are wrappers around sqlite_exec() and 354** sqlite_get_table(). The only difference between the routines that 355** follow and the originals is that the second argument to the 356** routines that follow is really a printf()-style format 357** string describing the SQL to be executed. Arguments to the format 358** string appear at the end of the argument list. 359** 360** All of the usual printf formatting options apply. In addition, there 361** is a "%q" option. %q works like %s in that it substitutes a null-terminated 362** string from the argument list. But %q also doubles every '\'' character. 363** %q is designed for use inside a string literal. By doubling each '\'' 364** character it escapes that character and allows it to be inserted into 365** the string. 366** 367** For example, so some string variable contains text as follows: 368** 369** char *zText = "It's a happy day!"; 370** 371** We can use this text in an SQL statement as follows: 372** 373** sqlite_exec_printf(db, "INSERT INTO table VALUES('%q')", 374** callback1, 0, 0, zText); 375** 376** Because the %q format string is used, the '\'' character in zText 377** is escaped and the SQL generated is as follows: 378** 379** INSERT INTO table1 VALUES('It''s a happy day!') 380** 381** This is correct. Had we used %s instead of %q, the generated SQL 382** would have looked like this: 383** 384** INSERT INTO table1 VALUES('It's a happy day!'); 385** 386** This second example is an SQL syntax error. As a general rule you 387** should always use %q instead of %s when inserting text into a string 388** literal. 389*/ 390int sqlite_exec_printf( 391 sqlite*, /* An open database */ 392 const char *sqlFormat, /* printf-style format string for the SQL */ 393 sqlite_callback, /* Callback function */ 394 void *, /* 1st argument to callback function */ 395 char **errmsg, /* Error msg written here */ 396 ... /* Arguments to the format string. */ 397); 398int sqlite_exec_vprintf( 399 sqlite*, /* An open database */ 400 const char *sqlFormat, /* printf-style format string for the SQL */ 401 sqlite_callback, /* Callback function */ 402 void *, /* 1st argument to callback function */ 403 char **errmsg, /* Error msg written here */ 404 va_list ap /* Arguments to the format string. */ 405); 406int sqlite_get_table_printf( 407 sqlite*, /* An open database */ 408 const char *sqlFormat, /* printf-style format string for the SQL */ 409 char ***resultp, /* Result written to a char *[] that this points to */ 410 int *nrow, /* Number of result rows written here */ 411 int *ncolumn, /* Number of result columns written here */ 412 char **errmsg, /* Error msg written here */ 413 ... /* Arguments to the format string */ 414); 415int sqlite_get_table_vprintf( 416 sqlite*, /* An open database */ 417 const char *sqlFormat, /* printf-style format string for the SQL */ 418 char ***resultp, /* Result written to a char *[] that this points to */ 419 int *nrow, /* Number of result rows written here */ 420 int *ncolumn, /* Number of result columns written here */ 421 char **errmsg, /* Error msg written here */ 422 va_list ap /* Arguments to the format string */ 423); 424char *sqlite_mprintf(const char*,...); 425char *sqlite_vmprintf(const char*, va_list); 426 427/* 428** Windows systems should call this routine to free memory that 429** is returned in the in the errmsg parameter of sqlite_open() when 430** SQLite is a DLL. For some reason, it does not work to call free() 431** directly. 432*/ 433void sqlite_freemem(void *p); 434 435/* 436** Windows systems need functions to call to return the sqlite_version 437** and sqlite_encoding strings. 438*/ 439const char *sqlite_libversion(void); 440const char *sqlite_libencoding(void); 441 442/* 443** A pointer to the following structure is used to communicate with 444** the implementations of user-defined functions. 445*/ 446typedef struct sqlite_func sqlite_func; 447 448/* 449** Use the following routines to create new user-defined functions. See 450** the documentation for details. 451*/ 452int sqlite_create_function( 453 sqlite*, /* Database where the new function is registered */ 454 const char *zName, /* Name of the new function */ 455 int nArg, /* Number of arguments. -1 means any number */ 456 void (*xFunc)(sqlite_func*,int,const char**), /* C code to implement */ 457 void *pUserData /* Available via the sqlite_user_data() call */ 458); 459int sqlite_create_aggregate( 460 sqlite*, /* Database where the new function is registered */ 461 const char *zName, /* Name of the function */ 462 int nArg, /* Number of arguments */ 463 void (*xStep)(sqlite_func*,int,const char**), /* Called for each row */ 464 void (*xFinalize)(sqlite_func*), /* Called once to get final result */ 465 void *pUserData /* Available via the sqlite_user_data() call */ 466); 467 468/* 469** Use the following routine to define the datatype returned by a 470** user-defined function. The second argument can be one of the 471** constants SQLITE_NUMERIC, SQLITE_TEXT, or SQLITE_ARGS or it 472** can be an integer greater than or equal to zero. When the datatype 473** parameter is non-negative, the type of the result will be the 474** same as the datatype-th argument. If datatype==SQLITE_NUMERIC 475** then the result is always numeric. If datatype==SQLITE_TEXT then 476** the result is always text. If datatype==SQLITE_ARGS then the result 477** is numeric if any argument is numeric and is text otherwise. 478*/ 479int sqlite_function_type( 480 sqlite *db, /* The database there the function is registered */ 481 const char *zName, /* Name of the function */ 482 int datatype /* The datatype for this function */ 483); 484#define SQLITE_NUMERIC (-1) 485#define SQLITE_TEXT (-2) 486#define SQLITE_ARGS (-3) 487 488/* 489** The user function implementations call one of the following four routines 490** in order to return their results. The first parameter to each of these 491** routines is a copy of the first argument to xFunc() or xFinialize(). 492** The second parameter to these routines is the result to be returned. 493** A NULL can be passed as the second parameter to sqlite_set_result_string() 494** in order to return a NULL result. 495** 496** The 3rd argument to _string and _error is the number of characters to 497** take from the string. If this argument is negative, then all characters 498** up to and including the first '\000' are used. 499** 500** The sqlite_set_result_string() function allocates a buffer to hold the 501** result and returns a pointer to this buffer. The calling routine 502** (that is, the implmentation of a user function) can alter the content 503** of this buffer if desired. 504*/ 505char *sqlite_set_result_string(sqlite_func*,const char*,int); 506void sqlite_set_result_int(sqlite_func*,int); 507void sqlite_set_result_double(sqlite_func*,double); 508void sqlite_set_result_error(sqlite_func*,const char*,int); 509 510/* 511** The pUserData parameter to the sqlite_create_function() and 512** sqlite_create_aggregate() routines used to register user functions 513** is available to the implementation of the function using this 514** call. 515*/ 516void *sqlite_user_data(sqlite_func*); 517 518/* 519** Aggregate functions use the following routine to allocate 520** a structure for storing their state. The first time this routine 521** is called for a particular aggregate, a new structure of size nBytes 522** is allocated, zeroed, and returned. On subsequent calls (for the 523** same aggregate instance) the same buffer is returned. The implementation 524** of the aggregate can use the returned buffer to accumulate data. 525** 526** The buffer allocated is freed automatically be SQLite. 527*/ 528void *sqlite_aggregate_context(sqlite_func*, int nBytes); 529 530/* 531** The next routine returns the number of calls to xStep for a particular 532** aggregate function instance. The current call to xStep counts so this 533** routine always returns at least 1. 534*/ 535int sqlite_aggregate_count(sqlite_func*); 536 537/* 538** This routine registers a callback with the SQLite library. The 539** callback is invoked (at compile-time, not at run-time) for each 540** attempt to access a column of a table in the database. The callback 541** returns SQLITE_OK if access is allowed, SQLITE_DENY if the entire 542** SQL statement should be aborted with an error and SQLITE_IGNORE 543** if the column should be treated as a NULL value. 544*/ 545int sqlite_set_authorizer( 546 sqlite*, 547 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 548 void *pUserData 549); 550 551/* 552** The second parameter to the access authorization function above will 553** be one of the values below. These values signify what kind of operation 554** is to be authorized. The 3rd and 4th parameters to the authorization 555** function will be parameters or NULL depending on which of the following 556** codes is used as the second parameter. The 5th parameter is the name 557** of the database ("main", "temp", etc.) if applicable. The 6th parameter 558** is the name of the inner-most trigger or view that is responsible for 559** the access attempt or NULL if this access attempt is directly from 560** input SQL code. 561** 562** Arg-3 Arg-4 563*/ 564#define SQLITE_COPY 0 /* Table Name File Name */ 565#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 566#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 567#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 568#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 569#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 570#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 571#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 572#define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 573#define SQLITE_DELETE 9 /* Table Name NULL */ 574#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 575#define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 576#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 577#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 578#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 579#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 580#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 581#define SQLITE_DROP_VIEW 17 /* View Name NULL */ 582#define SQLITE_INSERT 18 /* Table Name NULL */ 583#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 584#define SQLITE_READ 20 /* Table Name Column Name */ 585#define SQLITE_SELECT 21 /* NULL NULL */ 586#define SQLITE_TRANSACTION 22 /* NULL NULL */ 587#define SQLITE_UPDATE 23 /* Table Name Column Name */ 588#define SQLITE_ATTACH 24 /* Filename NULL */ 589#define SQLITE_DETACH 25 /* Database Name NULL */ 590 591 592/* 593** The return value of the authorization function should be one of the 594** following constants: 595*/ 596/* #define SQLITE_OK 0 // Allow access (This is actually defined above) */ 597#define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 598#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 599 600/* 601** Register a function that is called at every invocation of sqlite_exec() 602** or sqlite_compile(). This function can be used (for example) to generate 603** a log file of all SQL executed against a database. 604*/ 605void *sqlite_trace(sqlite*, void(*xTrace)(void*,const char*), void*); 606 607/*** The Callback-Free API 608** 609** The following routines implement a new way to access SQLite that does not 610** involve the use of callbacks. 611** 612** An sqlite_vm is an opaque object that represents a single SQL statement 613** that is ready to be executed. 614*/ 615typedef struct sqlite_vm sqlite_vm; 616 617/* 618** To execute an SQLite query without the use of callbacks, you first have 619** to compile the SQL using this routine. The 1st parameter "db" is a pointer 620** to an sqlite object obtained from sqlite_open(). The 2nd parameter 621** "zSql" is the text of the SQL to be compiled. The remaining parameters 622** are all outputs. 623** 624** *pzTail is made to point to the first character past the end of the first 625** SQL statement in zSql. This routine only compiles the first statement 626** in zSql, so *pzTail is left pointing to what remains uncompiled. 627** 628** *ppVm is left pointing to a "virtual machine" that can be used to execute 629** the compiled statement. Or if there is an error, *ppVm may be set to NULL. 630** If the input text contained no SQL (if the input is and empty string or 631** a comment) then *ppVm is set to NULL. 632** 633** If any errors are detected during compilation, an error message is written 634** into space obtained from malloc() and *pzErrMsg is made to point to that 635** error message. The calling routine is responsible for freeing the text 636** of this message when it has finished with it. Use sqlite_freemem() to 637** free the message. pzErrMsg may be NULL in which case no error message 638** will be generated. 639** 640** On success, SQLITE_OK is returned. Otherwise and error code is returned. 641*/ 642int sqlite_compile( 643 sqlite *db, /* The open database */ 644 const char *zSql, /* SQL statement to be compiled */ 645 const char **pzTail, /* OUT: uncompiled tail of zSql */ 646 sqlite_vm **ppVm, /* OUT: the virtual machine to execute zSql */ 647 char **pzErrmsg /* OUT: Error message. */ 648); 649 650/* 651** After an SQL statement has been compiled, it is handed to this routine 652** to be executed. This routine executes the statement as far as it can 653** go then returns. The return value will be one of SQLITE_DONE, 654** SQLITE_ERROR, SQLITE_BUSY, SQLITE_ROW, or SQLITE_MISUSE. 655** 656** SQLITE_DONE means that the execute of the SQL statement is complete 657** an no errors have occurred. sqlite_step() should not be called again 658** for the same virtual machine. *pN is set to the number of columns in 659** the result set and *pazColName is set to an array of strings that 660** describe the column names and datatypes. The name of the i-th column 661** is (*pazColName)[i] and the datatype of the i-th column is 662** (*pazColName)[i+*pN]. *pazValue is set to NULL. 663** 664** SQLITE_ERROR means that the virtual machine encountered a run-time 665** error. sqlite_step() should not be called again for the same 666** virtual machine. *pN is set to 0 and *pazColName and *pazValue are set 667** to NULL. Use sqlite_finalize() to obtain the specific error code 668** and the error message text for the error. 669** 670** SQLITE_BUSY means that an attempt to open the database failed because 671** another thread or process is holding a lock. The calling routine 672** can try again to open the database by calling sqlite_step() again. 673** The return code will only be SQLITE_BUSY if no busy handler is registered 674** using the sqlite_busy_handler() or sqlite_busy_timeout() routines. If 675** a busy handler callback has been registered but returns 0, then this 676** routine will return SQLITE_ERROR and sqltie_finalize() will return 677** SQLITE_BUSY when it is called. 678** 679** SQLITE_ROW means that a single row of the result is now available. 680** The data is contained in *pazValue. The value of the i-th column is 681** (*azValue)[i]. *pN and *pazColName are set as described in SQLITE_DONE. 682** Invoke sqlite_step() again to advance to the next row. 683** 684** SQLITE_MISUSE is returned if sqlite_step() is called incorrectly. 685** For example, if you call sqlite_step() after the virtual machine 686** has halted (after a prior call to sqlite_step() has returned SQLITE_DONE) 687** or if you call sqlite_step() with an incorrectly initialized virtual 688** machine or a virtual machine that has been deleted or that is associated 689** with an sqlite structure that has been closed. 690*/ 691int sqlite_step( 692 sqlite_vm *pVm, /* The virtual machine to execute */ 693 int *pN, /* OUT: Number of columns in result */ 694 const char ***pazValue, /* OUT: Column data */ 695 const char ***pazColName /* OUT: Column names and datatypes */ 696); 697 698/* 699** This routine is called to delete a virtual machine after it has finished 700** executing. The return value is the result code. SQLITE_OK is returned 701** if the statement executed successfully and some other value is returned if 702** there was any kind of error. If an error occurred and pzErrMsg is not 703** NULL, then an error message is written into memory obtained from malloc() 704** and *pzErrMsg is made to point to that error message. The calling routine 705** should use sqlite_freemem() to delete this message when it has finished 706** with it. 707** 708** This routine can be called at any point during the execution of the 709** virtual machine. If the virtual machine has not completed execution 710** when this routine is called, that is like encountering an error or 711** an interrupt. (See sqlite_interrupt().) Incomplete updates may be 712** rolled back and transactions cancelled, depending on the circumstances, 713** and the result code returned will be SQLITE_ABORT. 714*/ 715int sqlite_finalize(sqlite_vm*, char **pzErrMsg); 716 717/* 718** This routine deletes the virtual machine, writes any error message to 719** *pzErrMsg and returns an SQLite return code in the same way as the 720** sqlite_finalize() function. 721** 722** Additionally, if ppVm is not NULL, *ppVm is left pointing to a new virtual 723** machine loaded with the compiled version of the original query ready for 724** execution. 725** 726** If sqlite_reset() returns SQLITE_SCHEMA, then *ppVm is set to NULL. 727** 728******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 729*/ 730int sqlite_reset(sqlite_vm*, char **pzErrMsg); 731 732/* 733** If the SQL that was handed to sqlite_compile contains variables that 734** are represeted in the SQL text by a question mark ('?'). This routine 735** is used to assign values to those variables. 736** 737** The first parameter is a virtual machine obtained from sqlite_compile(). 738** The 2nd "idx" parameter determines which variable in the SQL statement 739** to bind the value to. The left most '?' is 1. The 3rd parameter is 740** the value to assign to that variable. The 4th parameter is the number 741** of bytes in the value, including the terminating \000 for strings. 742** Finally, the 5th "copy" parameter is TRUE if SQLite should make its 743** own private copy of this value, or false if the space that the 3rd 744** parameter points to will be unchanging and can be used directly by 745** SQLite. 746** 747** Unbound variables are treated as having a value of NULL. To explicitly 748** set a variable to NULL, call this routine with the 3rd parameter as a 749** NULL pointer. 750** 751** If the 4th "len" parameter is -1, then strlen() is used to find the 752** length. 753** 754** This routine can only be called immediately after sqlite_compile() 755** or sqlite_reset() and before any calls to sqlite_step(). 756** 757******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 758*/ 759int sqlite_bind(sqlite_vm*, int idx, const char *value, int len, int copy); 760 761/* 762** This routine configures a callback function - the progress callback - that 763** is invoked periodically during long running calls to sqlite_exec(), 764** sqlite_step() and sqlite_get_table(). An example use for this API is to keep 765** a GUI updated during a large query. 766** 767** The progress callback is invoked once for every N virtual machine opcodes, 768** where N is the second argument to this function. The progress callback 769** itself is identified by the third argument to this function. The fourth 770** argument to this function is a void pointer passed to the progress callback 771** function each time it is invoked. 772** 773** If a call to sqlite_exec(), sqlite_step() or sqlite_get_table() results 774** in less than N opcodes being executed, then the progress callback is not 775** invoked. 776** 777** Calling this routine overwrites any previously installed progress callback. 778** To remove the progress callback altogether, pass NULL as the third 779** argument to this function. 780** 781** If the progress callback returns a result other than 0, then the current 782** query is immediately terminated and any database changes rolled back. If the 783** query was part of a larger transaction, then the transaction is not rolled 784** back and remains active. The sqlite_exec() call returns SQLITE_ABORT. 785** 786******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 787*/ 788void sqlite_progress_handler(sqlite*, int, int(*)(void*), void*); 789 790/* 791** Register a callback function to be invoked whenever a new transaction 792** is committed. The pArg argument is passed through to the callback. 793** callback. If the callback function returns non-zero, then the commit 794** is converted into a rollback. 795** 796** If another function was previously registered, its pArg value is returned. 797** Otherwise NULL is returned. 798** 799** Registering a NULL function disables the callback. 800** 801******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** 802*/ 803void *sqlite_commit_hook(sqlite*, int(*)(void*), void*); 804 805/* 806** Open an encrypted SQLite database. If pKey==0 or nKey==0, this routine 807** is the same as sqlite_open(). 808** 809** The code to implement this API is not available in the public release 810** of SQLite. 811*/ 812sqlite *sqlite_open_encrypted( 813 const char *zFilename, /* Name of the encrypted database */ 814 const void *pKey, /* Pointer to the key */ 815 int nKey, /* Number of bytes in the key */ 816 int *pErrcode, /* Write error code here */ 817 char **pzErrmsg /* Write error message here */ 818); 819 820/* 821** Change the key on an open database. If the current database is not 822** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the 823** database is decrypted. 824** 825** The code to implement this API is not available in the public release 826** of SQLite. 827*/ 828int sqlite_rekey( 829 sqlite *db, /* Database to be rekeyed */ 830 const void *pKey, int nKey /* The new key */ 831); 832 833/* 834** Encode a binary buffer "in" of size n bytes so that it contains 835** no instances of characters '\'' or '\000'. The output is 836** null-terminated and can be used as a string value in an INSERT 837** or UPDATE statement. Use sqlite_decode_binary() to convert the 838** string back into its original binary. 839** 840** The result is written into a preallocated output buffer "out". 841** "out" must be able to hold at least 2 +(257*n)/254 bytes. 842** In other words, the output will be expanded by as much as 3 843** bytes for every 254 bytes of input plus 2 bytes of fixed overhead. 844** (This is approximately 2 + 1.0118*n or about a 1.2% size increase.) 845** 846** The return value is the number of characters in the encoded 847** string, excluding the "\000" terminator. 848** 849** If out==NULL then no output is generated but the routine still returns 850** the number of characters that would have been generated if out had 851** not been NULL. 852*/ 853int sqlite_encode_binary(const unsigned char *in, int n, unsigned char *out); 854 855/* 856** Decode the string "in" into binary data and write it into "out". 857** This routine reverses the encoding created by sqlite_encode_binary(). 858** The output will always be a few bytes less than the input. The number 859** of bytes of output is returned. If the input is not a well-formed 860** encoding, -1 is returned. 861** 862** The "in" and "out" parameters may point to the same buffer in order 863** to decode a string in place. 864*/ 865int sqlite_decode_binary(const unsigned char *in, unsigned char *out); 866 867#ifdef __cplusplus 868} /* End of the 'extern "C"' block */ 869#endif 870 871#endif /* _SQLITE_H_ */ 872