File Content: sqlite.h /* ** 2001 September 15 ** ** The author disclaims copyright to this source code. In place of ** a legal notice, here is a blessing: ** ** May you do good and not evil. ** May you find forgiveness for yourself and forgive others. ** May you share freely, never taking more than you give. ** ************************************************************************* ** This header file defines the interface that the SQLite library ** presents to client programs. ** ** @(#) $Id$ */ #ifndef _SQLITE_H_ #define _SQLITE_H_ #include <stdarg.h> /* Needed for the definition of va_list */ /* ** Make sure we can call this stuff from C++. */ #ifdef __cplusplus extern "C" { #endif /* ** The version of the SQLite library. */ #ifdef SQLITE_VERSION # undef SQLITE_VERSION #else # define SQLITE_VERSION "2.8.17" #endif /* ** The version string is also compiled into the library so that a program ** can check to make sure that the lib*.a file and the *.h file are from ** the same version. */ extern const char sqlite_version[]; /* ** The SQLITE_UTF8 macro is defined if the library expects to see ** UTF-8 encoded data. The SQLITE_ISO8859 macro is defined if the ** iso8859 encoded should be used. */ #define SQLITE_UTF8 1 /* ** The following constant holds one of two strings, "UTF-8" or "iso8859", ** depending on which character encoding the SQLite library expects to ** see. The character encoding makes a difference for the LIKE and GLOB ** operators and for the LENGTH() and SUBSTR() functions. */ extern const char sqlite_encoding[]; /* ** Each open sqlite database is represented by an instance of the ** following opaque structure. */ typedef struct sqlite sqlite; /* ** A function to open a new sqlite database. ** ** If the database does not exist and mode indicates write ** permission, then a new database is created. If the database ** does not exist and mode does not indicate write permission, ** then the open fails, an error message generated (if errmsg!=0) ** and the function returns 0. ** ** If mode does not indicates user write permission, then the ** database is opened read-only. ** ** The Truth: As currently implemented, all databases are opened ** for writing all the time. Maybe someday we will provide the ** ability to open a database readonly. The mode parameters is ** provided in anticipation of that enhancement. */ sqlite *sqlite_open(const char *filename, int mode, char **errmsg); /* ** A function to close the database. ** ** Call this function with a pointer to a structure that was previously ** returned from sqlite_open() and the corresponding database will by closed. */ void sqlite_close(sqlite *); /* ** The type for a callback function. */ typedef int (*sqlite_callback)(void*,int,char**, char**); /* ** A function to executes one or more statements of SQL. ** ** If one or more of the SQL statements are queries, then ** the callback function specified by the 3rd parameter is ** invoked once for each row of the query result. This callback ** should normally return 0. If the callback returns a non-zero ** value then the query is aborted, all subsequent SQL statements ** are skipped and the sqlite_exec() function returns the SQLITE_ABORT. ** ** The 4th parameter is an arbitrary pointer that is passed ** to the callback function as its first parameter. ** ** The 2nd parameter to the callback function is the number of ** columns in the query result. The 3rd parameter to the callback ** is an array of strings holding the values for each column. ** The 4th parameter to the callback is an array of strings holding ** the names of each column. ** ** The callback function may be NULL, even for queries. A NULL ** callback is not an error. It just means that no callback ** will be invoked. ** ** If an error occurs while parsing or evaluating the SQL (but ** not while executing the callback) then an appropriate error ** message is written into memory obtained from malloc() and ** *errmsg is made to point to that message. The calling function ** is responsible for freeing the memory that holds the error ** message. Use sqlite_freemem() for this. If errmsg==NULL, ** then no error message is ever written. ** ** The return value is is SQLITE_OK if there are no errors and ** some other return code if there is an error. The particular ** return value depends on the type of error. ** ** If the query could not be executed because a database file is ** locked or busy, then this function returns SQLITE_BUSY. (This ** behavior can be modified somewhat using the sqlite_busy_handler() ** and sqlite_busy_timeout() functions below.) */ int sqlite_exec( sqlite*, /* An open database */ const char *sql, /* SQL to be executed */ sqlite_callback, /* Callback function */ void *, /* 1st argument to callback function */ char **errmsg /* Error msg written here */ ); /* ** Return values for sqlite_exec() and sqlite_step() */ #define SQLITE_OK 0 /* Successful result */ #define SQLITE_ERROR 1 /* SQL error or missing database */ #define SQLITE_INTERNAL 2 /* An internal logic error in SQLite */ #define SQLITE_PERM 3 /* Access permission denied */ #define SQLITE_ABORT 4 /* Callback routine requested an abort */ #define SQLITE_BUSY 5 /* The database file is locked */ #define SQLITE_LOCKED 6 /* A table in the database is locked */ #define SQLITE_NOMEM 7 /* A malloc() failed */ #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite_interrupt() */ #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ #define SQLITE_NOTFOUND 12 /* (Internal Only) Table or record not found */ #define SQLITE_FULL 13 /* Insertion failed because database is full */ #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ #define SQLITE_PROTOCOL 15 /* Database lock protocol error */ #define SQLITE_EMPTY 16 /* (Internal Only) Database table is empty */ #define SQLITE_SCHEMA 17 /* The database schema changed */ #define SQLITE_TOOBIG 18 /* Too much data for one row of a table */ #define SQLITE_CONSTRAINT 19 /* Abort due to contraint violation */ #define SQLITE_MISMATCH 20 /* Data type mismatch */ #define SQLITE_MISUSE 21 /* Library used incorrectly */ #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ #define SQLITE_AUTH 23 /* Authorization denied */ #define SQLITE_FORMAT 24 /* Auxiliary database format error */ #define SQLITE_RANGE 25 /* 2nd parameter to sqlite_bind out of range */ #define SQLITE_NOTADB 26 /* File opened that is not a database file */ #define SQLITE_ROW 100 /* sqlite_step() has another row ready */ #define SQLITE_DONE 101 /* sqlite_step() has finished executing */ /* ** Each entry in an SQLite table has a unique integer key. (The key is ** the value of the INTEGER PRIMARY KEY column if there is such a column, ** otherwise the key is generated at random. The unique key is always ** available as the ROWID, OID, or _ROWID_ column.) The following routine ** returns the integer key of the most recent insert in the database. ** ** This function is similar to the mysql_insert_id() function from MySQL. */ int sqlite_last_insert_rowid(sqlite*); /* ** This function returns the number of database rows that were changed ** (or inserted or deleted) by the most recent called sqlite_exec(). ** ** All changes are counted, even if they were later undone by a ** ROLLBACK or ABORT. Except, changes associated with creating and ** dropping tables are not counted. ** ** If a callback invokes sqlite_exec() recursively, then the changes ** in the inner, recursive call are counted together with the changes ** in the outer call. ** ** SQLite implements the command "DELETE FROM table" without a WHERE clause ** by dropping and recreating the table. (This is much faster than going ** through and deleting individual elements form the table.) Because of ** this optimization, the change count for "DELETE FROM table" will be ** zero regardless of the number of elements that were originally in the ** table. To get an accurate count of the number of rows deleted, use ** "DELETE FROM table WHERE 1" instead. */ int sqlite_changes(sqlite*); /* ** This function returns the number of database rows that were changed ** by the last INSERT, UPDATE, or DELETE statment executed by sqlite_exec(), ** or by the last VM to run to completion. The change count is not updated ** by SQL statements other than INSERT, UPDATE or DELETE. ** ** Changes are counted, even if they are later undone by a ROLLBACK or ** ABORT. Changes associated with trigger programs that execute as a ** result of the INSERT, UPDATE, or DELETE statement are not counted. ** ** If a callback invokes sqlite_exec() recursively, then the changes ** in the inner, recursive call are counted together with the changes ** in the outer call. ** ** SQLite implements the command "DELETE FROM table" without a WHERE clause ** by dropping and recreating the table. (This is much faster than going ** through and deleting individual elements form the table.) Because of ** this optimization, the change count for "DELETE FROM table" will be ** zero regardless of the number of elements that were originally in the ** table. To get an accurate count of the number of rows deleted, use ** "DELETE FROM table WHERE 1" instead. ** ******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** */ int sqlite_last_statement_changes(sqlite*); /* If the parameter to this routine is one of the return value constants ** defined above, then this routine returns a constant text string which ** descripts (in English) the meaning of the return value. */ const char *sqlite_error_string(int); #define sqliteErrStr sqlite_error_string /* Legacy. Do not use in new code. */ /* This function causes any pending database operation to abort and ** return at its earliest opportunity. This routine is typically ** called in response to a user action such as pressing "Cancel" ** or Ctrl-C where the user wants a long query operation to halt ** immediately. */ void sqlite_interrupt(sqlite*); /* This function returns true if the given input string comprises ** one or more complete SQL statements. ** ** The algorithm is simple. If the last token other than spaces ** and comments is a semicolon, then return true. otherwise return ** false. */ int sqlite_complete(const char *sql); /* ** This routine identifies a callback function that is invoked ** whenever an attempt is made to open a database table that is ** currently locked by another process or thread. If the busy callback ** is NULL, then sqlite_exec() returns SQLITE_BUSY immediately if ** it finds a locked table. If the busy callback is not NULL, then ** sqlite_exec() invokes the callback with three arguments. The ** second argument is the name of the locked table and the third ** argument is the number of times the table has been busy. If the ** busy callback returns 0, then sqlite_exec() immediately returns ** SQLITE_BUSY. If the callback returns non-zero, then sqlite_exec() ** tries to open the table again and the cycle repeats. ** ** The default busy callback is NULL. ** ** Sqlite is re-entrant, so the busy handler may start a new query. ** (It is not clear why anyone would every want to do this, but it ** is allowed, in theory.) But the busy handler may not close the ** database. Closing the database from a busy handler will delete ** data structures out from under the executing query and will ** probably result in a coredump. */ void sqlite_busy_handler(sqlite*, int(*)(void*,const char*,int), void*); /* ** This routine sets a busy handler that sleeps for a while when a ** table is locked. The handler will sleep multiple times until ** at least "ms" milleseconds of sleeping have been done. After ** "ms" milleseconds of sleeping, the handler returns 0 which ** causes sqlite_exec() to return SQLITE_BUSY. ** ** Calling this routine with an argument less than or equal to zero ** turns off all busy handlers. */ void sqlite_busy_timeout(sqlite*, int ms); /* ** This next routine is really just a wrapper around sqlite_exec(). ** Instead of invoking a user-supplied callback for each row of the ** result, this routine remembers each row of the result in memory ** obtained from malloc(), then returns all of the result after the ** query has finished. ** ** As an example, suppose the query result where this table: ** ** Name | Age ** ----------------------- ** Alice | 43 ** Bob | 28 ** Cindy | 21 ** ** If the 3rd argument were &azResult then after the function returns ** azResult will contain the following data: ** ** azResult[0] = "Name"; ** azResult[1] = "Age"; ** azResult[2] = "Alice"; ** azResult[3] = "43"; ** azResult[4] = "Bob"; ** azResult[5] = "28"; ** azResult[6] = "Cindy"; ** azResult[7] = "21"; ** ** Notice that there is an extra row of data containing the column ** headers. But the *nrow return value is still 3. *ncolumn is ** set to 2. In general, the number of values inserted into azResult ** will be ((*nrow) + 1)*(*ncolumn). ** ** After the calling function has finished using the result, it should ** pass the result data pointer to sqlite_free_table() in order to ** release the memory that was malloc-ed. Because of the way the ** malloc() happens, the calling function must not try to call ** malloc() directly. Only sqlite_free_table() is able to release ** the memory properly and safely. ** ** The return value of this routine is the same as from sqlite_exec(). */ int sqlite_get_table( sqlite*, /* An open database */ const char *sql, /* SQL to be executed */ char ***resultp, /* Result written to a char *[] that this points to */ int *nrow, /* Number of result rows written here */ int *ncolumn, /* Number of result columns written here */ char **errmsg /* Error msg written here */ ); /* ** Call this routine to free the memory that sqlite_get_table() allocated. */ void sqlite_free_table(char **result); /* ** The following routines are wrappers around sqlite_exec() and ** sqlite_get_table(). The only difference between the routines that ** follow and the originals is that the second argument to the ** routines that follow is really a printf()-style format ** string describing the SQL to be executed. Arguments to the format ** string appear at the end of the argument list. ** ** All of the usual printf formatting options apply. In addition, there ** is a "%q" option. %q works like %s in that it substitutes a null-terminated ** string from the argument list. But %q also doubles every '\'' character. ** %q is designed for use inside a string literal. By doubling each '\'' ** character it escapes that character and allows it to be inserted into ** the string. ** ** For example, so some string variable contains text as follows: ** ** char *zText = "It's a happy day!"; ** ** We can use this text in an SQL statement as follows: ** ** sqlite_exec_printf(db, "INSERT INTO table VALUES('%q')", ** callback1, 0, 0, zText); ** ** Because the %q format string is used, the '\'' character in zText ** is escaped and the SQL generated is as follows: ** ** INSERT INTO table1 VALUES('It''s a happy day!') ** ** This is correct. Had we used %s instead of %q, the generated SQL ** would have looked like this: ** ** INSERT INTO table1 VALUES('It's a happy day!'); ** ** This second example is an SQL syntax error. As a general rule you ** should always use %q instead of %s when inserting text into a string ** literal. */ int sqlite_exec_printf( sqlite*, /* An open database */ const char *sqlFormat, /* printf-style format string for the SQL */ sqlite_callback, /* Callback function */ void *, /* 1st argument to callback function */ char **errmsg, /* Error msg written here */ ... /* Arguments to the format string. */ ); int sqlite_exec_vprintf( sqlite*, /* An open database */ const char *sqlFormat, /* printf-style format string for the SQL */ sqlite_callback, /* Callback function */ void *, /* 1st argument to callback function */ char **errmsg, /* Error msg written here */ va_list ap /* Arguments to the format string. */ ); int sqlite_get_table_printf( sqlite*, /* An open database */ const char *sqlFormat, /* printf-style format string for the SQL */ char ***resultp, /* Result written to a char *[] that this points to */ int *nrow, /* Number of result rows written here */ int *ncolumn, /* Number of result columns written here */ char **errmsg, /* Error msg written here */ ... /* Arguments to the format string */ ); int sqlite_get_table_vprintf( sqlite*, /* An open database */ const char *sqlFormat, /* printf-style format string for the SQL */ char ***resultp, /* Result written to a char *[] that this points to */ int *nrow, /* Number of result rows written here */ int *ncolumn, /* Number of result columns written here */ char **errmsg, /* Error msg written here */ va_list ap /* Arguments to the format string */ ); char *sqlite_mprintf(const char*,...); char *sqlite_vmprintf(const char*, va_list); /* ** Windows systems should call this routine to free memory that ** is returned in the in the errmsg parameter of sqlite_open() when ** SQLite is a DLL. For some reason, it does not work to call free() ** directly. */ void sqlite_freemem(void *p); /* ** Windows systems need functions to call to return the sqlite_version ** and sqlite_encoding strings. */ const char *sqlite_libversion(void); const char *sqlite_libencoding(void); /* ** A pointer to the following structure is used to communicate with ** the implementations of user-defined functions. */ typedef struct sqlite_func sqlite_func; /* ** Use the following routines to create new user-defined functions. See ** the documentation for details. */ int sqlite_create_function( sqlite*, /* Database where the new function is registered */ const char *zName, /* Name of the new function */ int nArg, /* Number of arguments. -1 means any number */ void (*xFunc)(sqlite_func*,int,const char**), /* C code to implement */ void *pUserData /* Available via the sqlite_user_data() call */ ); int sqlite_create_aggregate( sqlite*, /* Database where the new function is registered */ const char *zName, /* Name of the function */ int nArg, /* Number of arguments */ void (*xStep)(sqlite_func*,int,const char**), /* Called for each row */ void (*xFinalize)(sqlite_func*), /* Called once to get final result */ void *pUserData /* Available via the sqlite_user_data() call */ ); /* ** Use the following routine to define the datatype returned by a ** user-defined function. The second argument can be one of the ** constants SQLITE_NUMERIC, SQLITE_TEXT, or SQLITE_ARGS or it ** can be an integer greater than or equal to zero. When the datatype ** parameter is non-negative, the type of the result will be the ** same as the datatype-th argument. If datatype==SQLITE_NUMERIC ** then the result is always numeric. If datatype==SQLITE_TEXT then ** the result is always text. If datatype==SQLITE_ARGS then the result ** is numeric if any argument is numeric and is text otherwise. */ int sqlite_function_type( sqlite *db, /* The database there the function is registered */ const char *zName, /* Name of the function */ int datatype /* The datatype for this function */ ); #define SQLITE_NUMERIC (-1) /* #define SQLITE_TEXT (-2) // See below */ #define SQLITE_ARGS (-3) /* ** SQLite version 3 defines SQLITE_TEXT differently. To allow both ** version 2 and version 3 to be included, undefine them both if a ** conflict is seen. Define SQLITE2_TEXT to be the version 2 value. */ #ifdef SQLITE_TEXT # undef SQLITE_TEXT #else # define SQLITE_TEXT (-2) #endif #define SQLITE2_TEXT (-2) /* ** The user function implementations call one of the following four routines ** in order to return their results. The first parameter to each of these ** routines is a copy of the first argument to xFunc() or xFinialize(). ** The second parameter to these routines is the result to be returned. ** A NULL can be passed as the second parameter to sqlite_set_result_string() ** in order to return a NULL result. ** ** The 3rd argument to _string and _error is the number of characters to ** take from the string. If this argument is negative, then all characters ** up to and including the first '\000' are used. ** ** The sqlite_set_result_string() function allocates a buffer to hold the ** result and returns a pointer to this buffer. The calling routine ** (that is, the implmentation of a user function) can alter the content ** of this buffer if desired. */ char *sqlite_set_result_string(sqlite_func*,const char*,int); void sqlite_set_result_int(sqlite_func*,int); void sqlite_set_result_double(sqlite_func*,double); void sqlite_set_result_error(sqlite_func*,const char*,int); /* ** The pUserData parameter to the sqlite_create_function() and ** sqlite_create_aggregate() routines used to register user functions ** is available to the implementation of the function using this ** call. */ void *sqlite_user_data(sqlite_func*); /* ** Aggregate functions use the following routine to allocate ** a structure for storing their state. The first time this routine ** is called for a particular aggregate, a new structure of size nBytes ** is allocated, zeroed, and returned. On subsequent calls (for the ** same aggregate instance) the same buffer is returned. The implementation ** of the aggregate can use the returned buffer to accumulate data. ** ** The buffer allocated is freed automatically be SQLite. */ void *sqlite_aggregate_context(sqlite_func*, int nBytes); /* ** The next routine returns the number of calls to xStep for a particular ** aggregate function instance. The current call to xStep counts so this ** routine always returns at least 1. */ int sqlite_aggregate_count(sqlite_func*); /* ** This routine registers a callback with the SQLite library. The ** callback is invoked (at compile-time, not at run-time) for each ** attempt to access a column of a table in the database. The callback ** returns SQLITE_OK if access is allowed, SQLITE_DENY if the entire ** SQL statement should be aborted with an error and SQLITE_IGNORE ** if the column should be treated as a NULL value. */ int sqlite_set_authorizer( sqlite*, int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), void *pUserData ); /* ** The second parameter to the access authorization function above will ** be one of the values below. These values signify what kind of operation ** is to be authorized. The 3rd and 4th parameters to the authorization ** function will be parameters or NULL depending on which of the following ** codes is used as the second parameter. The 5th parameter is the name ** of the database ("main", "temp", etc.) if applicable. The 6th parameter ** is the name of the inner-most trigger or view that is responsible for ** the access attempt or NULL if this access attempt is directly from ** input SQL code. ** ** Arg-3 Arg-4 */ #define SQLITE_COPY 0 /* Table Name File Name */ #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ #define SQLITE_DELETE 9 /* Table Name NULL */ #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ #define SQLITE_DROP_VIEW 17 /* View Name NULL */ #define SQLITE_INSERT 18 /* Table Name NULL */ #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ #define SQLITE_READ 20 /* Table Name Column Name */ #define SQLITE_SELECT 21 /* NULL NULL */ #define SQLITE_TRANSACTION 22 /* NULL NULL */ #define SQLITE_UPDATE 23 /* Table Name Column Name */ #define SQLITE_ATTACH 24 /* Filename NULL */ #define SQLITE_DETACH 25 /* Database Name NULL */ /* ** The return value of the authorization function should be one of the ** following constants: */ /* #define SQLITE_OK 0 // Allow access (This is actually defined above) */ #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ /* ** Register a function that is called at every invocation of sqlite_exec() ** or sqlite_compile(). This function can be used (for example) to generate ** a log file of all SQL executed against a database. */ void *sqlite_trace(sqlite*, void(*xTrace)(void*,const char*), void*); /*** The Callback-Free API ** ** The following routines implement a new way to access SQLite that does not ** involve the use of callbacks. ** ** An sqlite_vm is an opaque object that represents a single SQL statement ** that is ready to be executed. */ typedef struct sqlite_vm sqlite_vm; /* ** To execute an SQLite query without the use of callbacks, you first have ** to compile the SQL using this routine. The 1st parameter "db" is a pointer ** to an sqlite object obtained from sqlite_open(). The 2nd parameter ** "zSql" is the text of the SQL to be compiled. The remaining parameters ** are all outputs. ** ** *pzTail is made to point to the first character past the end of the first ** SQL statement in zSql. This routine only compiles the first statement ** in zSql, so *pzTail is left pointing to what remains uncompiled. ** ** *ppVm is left pointing to a "virtual machine" that can be used to execute ** the compiled statement. Or if there is an error, *ppVm may be set to NULL. ** If the input text contained no SQL (if the input is and empty string or ** a comment) then *ppVm is set to NULL. ** ** If any errors are detected during compilation, an error message is written ** into space obtained from malloc() and *pzErrMsg is made to point to that ** error message. The calling routine is responsible for freeing the text ** of this message when it has finished with it. Use sqlite_freemem() to ** free the message. pzErrMsg may be NULL in which case no error message ** will be generated. ** ** On success, SQLITE_OK is returned. Otherwise and error code is returned. */ int sqlite_compile( sqlite *db, /* The open database */ const char *zSql, /* SQL statement to be compiled */ const char **pzTail, /* OUT: uncompiled tail of zSql */ sqlite_vm **ppVm, /* OUT: the virtual machine to execute zSql */ char **pzErrmsg /* OUT: Error message. */ ); /* ** After an SQL statement has been compiled, it is handed to this routine ** to be executed. This routine executes the statement as far as it can ** go then returns. The return value will be one of SQLITE_DONE, ** SQLITE_ERROR, SQLITE_BUSY, SQLITE_ROW, or SQLITE_MISUSE. ** ** SQLITE_DONE means that the execute of the SQL statement is complete ** an no errors have occurred. sqlite_step() should not be called again ** for the same virtual machine. *pN is set to the number of columns in ** the result set and *pazColName is set to an array of strings that ** describe the column names and datatypes. The name of the i-th column ** is (*pazColName)[i] and the datatype of the i-th column is ** (*pazColName)[i+*pN]. *pazValue is set to NULL. ** ** SQLITE_ERROR means that the virtual machine encountered a run-time ** error. sqlite_step() should not be called again for the same ** virtual machine. *pN is set to 0 and *pazColName and *pazValue are set ** to NULL. Use sqlite_finalize() to obtain the specific error code ** and the error message text for the error. ** ** SQLITE_BUSY means that an attempt to open the database failed because ** another thread or process is holding a lock. The calling routine ** can try again to open the database by calling sqlite_step() again. ** The return code will only be SQLITE_BUSY if no busy handler is registered ** using the sqlite_busy_handler() or sqlite_busy_timeout() routines. If ** a busy handler callback has been registered but returns 0, then this ** routine will return SQLITE_ERROR and sqltie_finalize() will return ** SQLITE_BUSY when it is called. ** ** SQLITE_ROW means that a single row of the result is now available. ** The data is contained in *pazValue. The value of the i-th column is ** (*azValue)[i]. *pN and *pazColName are set as described in SQLITE_DONE. ** Invoke sqlite_step() again to advance to the next row. ** ** SQLITE_MISUSE is returned if sqlite_step() is called incorrectly. ** For example, if you call sqlite_step() after the virtual machine ** has halted (after a prior call to sqlite_step() has returned SQLITE_DONE) ** or if you call sqlite_step() with an incorrectly initialized virtual ** machine or a virtual machine that has been deleted or that is associated ** with an sqlite structure that has been closed. */ int sqlite_step( sqlite_vm *pVm, /* The virtual machine to execute */ int *pN, /* OUT: Number of columns in result */ const char ***pazValue, /* OUT: Column data */ const char ***pazColName /* OUT: Column names and datatypes */ ); /* ** This routine is called to delete a virtual machine after it has finished ** executing. The return value is the result code. SQLITE_OK is returned ** if the statement executed successfully and some other value is returned if ** there was any kind of error. If an error occurred and pzErrMsg is not ** NULL, then an error message is written into memory obtained from malloc() ** and *pzErrMsg is made to point to that error message. The calling routine ** should use sqlite_freemem() to delete this message when it has finished ** with it. ** ** This routine can be called at any point during the execution of the ** virtual machine. If the virtual machine has not completed execution ** when this routine is called, that is like encountering an error or ** an interrupt. (See sqlite_interrupt().) Incomplete updates may be ** rolled back and transactions cancelled, depending on the circumstances, ** and the result code returned will be SQLITE_ABORT. */ int sqlite_finalize(sqlite_vm*, char **pzErrMsg); /* ** This routine deletes the virtual machine, writes any error message to ** *pzErrMsg and returns an SQLite return code in the same way as the ** sqlite_finalize() function. ** ** Additionally, if ppVm is not NULL, *ppVm is left pointing to a new virtual ** machine loaded with the compiled version of the original query ready for ** execution. ** ** If sqlite_reset() returns SQLITE_SCHEMA, then *ppVm is set to NULL. ** ******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** */ int sqlite_reset(sqlite_vm*, char **pzErrMsg); /* ** If the SQL that was handed to sqlite_compile contains variables that ** are represeted in the SQL text by a question mark ('?'). This routine ** is used to assign values to those variables. ** ** The first parameter is a virtual machine obtained from sqlite_compile(). ** The 2nd "idx" parameter determines which variable in the SQL statement ** to bind the value to. The left most '?' is 1. The 3rd parameter is ** the value to assign to that variable. The 4th parameter is the number ** of bytes in the value, including the terminating \000 for strings. ** Finally, the 5th "copy" parameter is TRUE if SQLite should make its ** own private copy of this value, or false if the space that the 3rd ** parameter points to will be unchanging and can be used directly by ** SQLite. ** ** Unbound variables are treated as having a value of NULL. To explicitly ** set a variable to NULL, call this routine with the 3rd parameter as a ** NULL pointer. ** ** If the 4th "len" parameter is -1, then strlen() is used to find the ** length. ** ** This routine can only be called immediately after sqlite_compile() ** or sqlite_reset() and before any calls to sqlite_step(). ** ******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** */ int sqlite_bind(sqlite_vm*, int idx, const char *value, int len, int copy); /* ** This routine configures a callback function - the progress callback - that ** is invoked periodically during long running calls to sqlite_exec(), ** sqlite_step() and sqlite_get_table(). An example use for this API is to keep ** a GUI updated during a large query. ** ** The progress callback is invoked once for every N virtual machine opcodes, ** where N is the second argument to this function. The progress callback ** itself is identified by the third argument to this function. The fourth ** argument to this function is a void pointer passed to the progress callback ** function each time it is invoked. ** ** If a call to sqlite_exec(), sqlite_step() or sqlite_get_table() results ** in less than N opcodes being executed, then the progress callback is not ** invoked. ** ** Calling this routine overwrites any previously installed progress callback. ** To remove the progress callback altogether, pass NULL as the third ** argument to this function. ** ** If the progress callback returns a result other than 0, then the current ** query is immediately terminated and any database changes rolled back. If the ** query was part of a larger transaction, then the transaction is not rolled ** back and remains active. The sqlite_exec() call returns SQLITE_ABORT. ** ******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** */ void sqlite_progress_handler(sqlite*, int, int(*)(void*), void*); /* ** Register a callback function to be invoked whenever a new transaction ** is committed. The pArg argument is passed through to the callback. ** callback. If the callback function returns non-zero, then the commit ** is converted into a rollback. ** ** If another function was previously registered, its pArg value is returned. ** Otherwise NULL is returned. ** ** Registering a NULL function disables the callback. ** ******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ****** */ void *sqlite_commit_hook(sqlite*, int(*)(void*), void*); /* ** Open an encrypted SQLite database. If pKey==0 or nKey==0, this routine ** is the same as sqlite_open(). ** ** The code to implement this API is not available in the public release ** of SQLite. */ sqlite *sqlite_open_encrypted( const char *zFilename, /* Name of the encrypted database */ const void *pKey, /* Pointer to the key */ int nKey, /* Number of bytes in the key */ int *pErrcode, /* Write error code here */ char **pzErrmsg /* Write error message here */ ); /* ** Change the key on an open database. If the current database is not ** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the ** database is decrypted. ** ** The code to implement this API is not available in the public release ** of SQLite. */ int sqlite_rekey( sqlite *db, /* Database to be rekeyed */ const void *pKey, int nKey /* The new key */ ); /* ** Encode a binary buffer "in" of size n bytes so that it contains ** no instances of characters '\'' or '\000'. The output is ** null-terminated and can be used as a string value in an INSERT ** or UPDATE statement. Use sqlite_decode_binary() to convert the ** string back into its original binary. ** ** The result is written into a preallocated output buffer "out". ** "out" must be able to hold at least 2 +(257*n)/254 bytes. ** In other words, the output will be expanded by as much as 3 ** bytes for every 254 bytes of input plus 2 bytes of fixed overhead. ** (This is approximately 2 + 1.0118*n or about a 1.2% size increase.) ** ** The return value is the number of characters in the encoded ** string, excluding the "\000" terminator. ** ** If out==NULL then no output is generated but the routine still returns ** the number of characters that would have been generated if out had ** not been NULL. */ int sqlite_encode_binary(const unsigned char *in, int n, unsigned char *out); /* ** Decode the string "in" into binary data and write it into "out". ** This routine reverses the encoding created by sqlite_encode_binary(). ** The output will always be a few bytes less than the input. The number ** of bytes of output is returned. If the input is not a well-formed ** encoding, -1 is returned. ** ** The "in" and "out" parameters may point to the same buffer in order ** to decode a string in place. */ int sqlite_decode_binary(const unsigned char *in, unsigned char *out); #ifdef __cplusplus } /* End of the 'extern "C"' block */ #endif #endif /* _SQLITE_H_ */ Submit