/* ** 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. ** ************************************************************************* ** Main file for the SQLite library. The routines in this file ** implement the programmer interface to the library. Routines in ** other files are for internal use by SQLite and should not be ** accessed by users of the library. ** ** $Id: main.c,v 1.161 2004/02/25 22:51:06 rdc Exp $ */ #include "sqliteInt.h" #include "os.h" #include /* ** A pointer to this structure is used to communicate information ** from sqliteInit into the sqliteInitCallback. */ typedef struct { sqlite *db; /* The database being initialized */ char **pzErrMsg; /* Error message stored here */ } InitData; /* ** Fill the InitData structure with an error message that indicates ** that the database is corrupt. */ static void corruptSchema(InitData *pData, const char *zExtra){ sqliteSetString(pData->pzErrMsg, "malformed database schema", zExtra!=0 && zExtra[0]!=0 ? " - " : (char*)0, zExtra, (char*)0); } /* ** This is the callback routine for the code that initializes the ** database. See sqliteInit() below for additional information. ** ** Each callback contains the following information: ** ** argv[0] = "file-format" or "schema-cookie" or "table" or "index" ** argv[1] = table or index name or meta statement type. ** argv[2] = root page number for table or index. NULL for meta. ** argv[3] = SQL text for a CREATE TABLE or CREATE INDEX statement. ** argv[4] = "1" for temporary files, "0" for main database, "2" or more ** for auxiliary database files. ** */ static int sqliteInitCallback(void *pInit, int argc, char **argv, char **azColName){ InitData *pData = (InitData*)pInit; int nErr = 0; assert( argc==5 ); if( argv==0 ) return 0; /* Might happen if EMPTY_RESULT_CALLBACKS are on */ if( argv[0]==0 ){ corruptSchema(pData, 0); return 1; } switch( argv[0][0] ){ case 'v': case 'i': case 't': { /* CREATE TABLE, CREATE INDEX, or CREATE VIEW statements */ sqlite *db = pData->db; if( argv[2]==0 || argv[4]==0 ){ corruptSchema(pData, 0); return 1; } if( argv[3] && argv[3][0] ){ /* Call the parser to process a CREATE TABLE, INDEX or VIEW. ** But because db->init.busy is set to 1, no VDBE code is generated ** or executed. All the parser does is build the internal data ** structures that describe the table, index, or view. */ char *zErr; assert( db->init.busy ); db->init.iDb = atoi(argv[4]); assert( db->init.iDb>=0 && db->init.iDbnDb ); db->init.newTnum = atoi(argv[2]); if( sqlite_exec(db, argv[3], 0, 0, &zErr) ){ corruptSchema(pData, zErr); sqlite_freemem(zErr); } db->init.iDb = 0; }else{ /* If the SQL column is blank it means this is an index that ** was created to be the PRIMARY KEY or to fulfill a UNIQUE ** constraint for a CREATE TABLE. The index should have already ** been created when we processed the CREATE TABLE. All we have ** to do here is record the root page number for that index. */ int iDb; Index *pIndex; iDb = atoi(argv[4]); assert( iDb>=0 && iDbnDb ); pIndex = sqliteFindIndex(db, argv[1], db->aDb[iDb].zName); if( pIndex==0 || pIndex->tnum!=0 ){ /* This can occur if there exists an index on a TEMP table which ** has the same name as another index on a permanent index. Since ** the permanent table is hidden by the TEMP table, we can also ** safely ignore the index on the permanent table. */ /* Do Nothing */; }else{ pIndex->tnum = atoi(argv[2]); } } break; } default: { /* This can not happen! */ nErr = 1; assert( nErr==0 ); } } return nErr; } /* ** This is a callback procedure used to reconstruct a table. The ** name of the table to be reconstructed is passed in as argv[0]. ** ** This routine is used to automatically upgrade a database from ** format version 1 or 2 to version 3. The correct operation of ** this routine relys on the fact that no indices are used when ** copying a table out to a temporary file. ** ** The change from version 2 to version 3 occurred between SQLite ** version 2.5.6 and 2.6.0 on 2002-July-18. */ static int upgrade_3_callback(void *pInit, int argc, char **argv, char **NotUsed){ InitData *pData = (InitData*)pInit; int rc; Table *pTab; Trigger *pTrig; char *zErr = 0; pTab = sqliteFindTable(pData->db, argv[0], 0); assert( pTab!=0 ); assert( sqliteStrICmp(pTab->zName, argv[0])==0 ); if( pTab ){ pTrig = pTab->pTrigger; pTab->pTrigger = 0; /* Disable all triggers before rebuilding the table */ } rc = sqlite_exec_printf(pData->db, "CREATE TEMP TABLE sqlite_x AS SELECT * FROM '%q'; " "DELETE FROM '%q'; " "INSERT INTO '%q' SELECT * FROM sqlite_x; " "DROP TABLE sqlite_x;", 0, 0, &zErr, argv[0], argv[0], argv[0]); if( zErr ){ if( *pData->pzErrMsg ) sqlite_freemem(*pData->pzErrMsg); *pData->pzErrMsg = zErr; } /* If an error occurred in the SQL above, then the transaction will ** rollback which will delete the internal symbol tables. This will ** cause the structure that pTab points to be deleted. In case that ** happened, we need to refetch pTab. */ pTab = sqliteFindTable(pData->db, argv[0], 0); if( pTab ){ assert( sqliteStrICmp(pTab->zName, argv[0])==0 ); pTab->pTrigger = pTrig; /* Re-enable triggers */ } return rc!=SQLITE_OK; } /* ** Attempt to read the database schema and initialize internal ** data structures for a single database file. The index of the ** database file is given by iDb. iDb==0 is used for the main ** database. iDb==1 should never be used. iDb>=2 is used for ** auxiliary databases. Return one of the SQLITE_ error codes to ** indicate success or failure. */ static int sqliteInitOne(sqlite *db, int iDb, char **pzErrMsg){ int rc; BtCursor *curMain; int size; Table *pTab; char *azArg[6]; char zDbNum[30]; int meta[SQLITE_N_BTREE_META]; InitData initData; /* ** The master database table has a structure like this */ static char master_schema[] = "CREATE TABLE sqlite_master(\n" " type text,\n" " name text,\n" " tbl_name text,\n" " rootpage integer,\n" " sql text\n" ")" ; static char temp_master_schema[] = "CREATE TEMP TABLE sqlite_temp_master(\n" " type text,\n" " name text,\n" " tbl_name text,\n" " rootpage integer,\n" " sql text\n" ")" ; /* The following SQL will read the schema from the master tables. ** The first version works with SQLite file formats 2 or greater. ** The second version is for format 1 files. ** ** Beginning with file format 2, the rowid for new table entries ** (including entries in sqlite_master) is an increasing integer. ** So for file format 2 and later, we can play back sqlite_master ** and all the CREATE statements will appear in the right order. ** But with file format 1, table entries were random and so we ** have to make sure the CREATE TABLEs occur before their corresponding ** CREATE INDEXs. (We don't have to deal with CREATE VIEW or ** CREATE TRIGGER in file format 1 because those constructs did ** not exist then.) */ static char init_script[] = "SELECT type, name, rootpage, sql, 1 FROM sqlite_temp_master " "UNION ALL " "SELECT type, name, rootpage, sql, 0 FROM sqlite_master"; static char older_init_script[] = "SELECT type, name, rootpage, sql, 1 FROM sqlite_temp_master " "UNION ALL " "SELECT type, name, rootpage, sql, 0 FROM sqlite_master " "WHERE type='table' " "UNION ALL " "SELECT type, name, rootpage, sql, 0 FROM sqlite_master " "WHERE type='index'"; assert( iDb>=0 && iDb!=1 && iDbnDb ); /* Construct the schema tables: sqlite_master and sqlite_temp_master */ sqliteSafetyOff(db); azArg[0] = "table"; azArg[1] = MASTER_NAME; azArg[2] = "2"; azArg[3] = master_schema; sprintf(zDbNum, "%d", iDb); azArg[4] = zDbNum; azArg[5] = 0; initData.db = db; initData.pzErrMsg = pzErrMsg; sqliteInitCallback(&initData, 5, azArg, 0); pTab = sqliteFindTable(db, MASTER_NAME, "main"); if( pTab ){ pTab->readOnly = 1; } if( iDb==0 ){ azArg[1] = TEMP_MASTER_NAME; azArg[3] = temp_master_schema; azArg[4] = "1"; sqliteInitCallback(&initData, 5, azArg, 0); pTab = sqliteFindTable(db, TEMP_MASTER_NAME, "temp"); if( pTab ){ pTab->readOnly = 1; } } sqliteSafetyOn(db); /* Create a cursor to hold the database open */ if( db->aDb[iDb].pBt==0 ) return SQLITE_OK; rc = sqliteBtreeCursor(db->aDb[iDb].pBt, 2, 0, &curMain); if( rc ){ sqliteSetString(pzErrMsg, sqlite_error_string(rc), (char*)0); return rc; } /* Get the database meta information */ rc = sqliteBtreeGetMeta(db->aDb[iDb].pBt, meta); if( rc ){ sqliteSetString(pzErrMsg, sqlite_error_string(rc), (char*)0); sqliteBtreeCloseCursor(curMain); return rc; } db->aDb[iDb].schema_cookie = meta[1]; if( iDb==0 ){ db->next_cookie = meta[1]; db->file_format = meta[2]; size = meta[3]; if( size==0 ){ size = MAX_PAGES; } db->cache_size = size; db->safety_level = meta[4]; if( db->safety_level==0 ) db->safety_level = 2; /* ** file_format==1 Version 2.1.0. ** file_format==2 Version 2.2.0. Add support for INTEGER PRIMARY KEY. ** file_format==3 Version 2.6.0. Fix empty-string index bug. ** file_format==4 Version 2.7.0. Add support for separate numeric and ** text datatypes. */ if( db->file_format==0 ){ /* This happens if the database was initially empty */ db->file_format = 4; }else if( db->file_format>4 ){ sqliteBtreeCloseCursor(curMain); sqliteSetString(pzErrMsg, "unsupported file format", (char*)0); return SQLITE_ERROR; } }else if( db->file_format!=meta[2] || db->file_format<4 ){ assert( db->file_format>=4 ); if( meta[2]==0 ){ sqliteSetString(pzErrMsg, "cannot attach empty database: ", db->aDb[iDb].zName, (char*)0); }else{ sqliteSetString(pzErrMsg, "incompatible file format in auxiliary " "database: ", db->aDb[iDb].zName, (char*)0); } sqliteBtreeClose(db->aDb[iDb].pBt); db->aDb[iDb].pBt = 0; return SQLITE_FORMAT; } sqliteBtreeSetCacheSize(db->aDb[iDb].pBt, db->cache_size); sqliteBtreeSetSafetyLevel(db->aDb[iDb].pBt, meta[4]==0 ? 2 : meta[4]); /* Read the schema information out of the schema tables */ assert( db->init.busy ); sqliteSafetyOff(db); if( iDb==0 ){ rc = sqlite_exec(db, db->file_format>=2 ? init_script : older_init_script, sqliteInitCallback, &initData, 0); }else{ char *zSql = 0; sqliteSetString(&zSql, "SELECT type, name, rootpage, sql, ", zDbNum, " FROM \"", db->aDb[iDb].zName, "\".sqlite_master", (char*)0); rc = sqlite_exec(db, zSql, sqliteInitCallback, &initData, 0); sqliteFree(zSql); } sqliteSafetyOn(db); sqliteBtreeCloseCursor(curMain); if( sqlite_malloc_failed ){ sqliteSetString(pzErrMsg, "out of memory", (char*)0); rc = SQLITE_NOMEM; sqliteResetInternalSchema(db, 0); } if( rc==SQLITE_OK ){ DbSetProperty(db, iDb, DB_SchemaLoaded); if( iDb==0 ){ DbSetProperty(db, 1, DB_SchemaLoaded); } }else{ sqliteResetInternalSchema(db, iDb); } return rc; } /* ** Initialize all database files - the main database file, the file ** used to store temporary tables, and any additional database files ** created using ATTACH statements. Return a success code. If an ** error occurs, write an error message into *pzErrMsg. ** ** After the database is initialized, the SQLITE_Initialized ** bit is set in the flags field of the sqlite structure. An ** attempt is made to initialize the database as soon as it ** is opened. If that fails (perhaps because another process ** has the sqlite_master table locked) than another attempt ** is made the first time the database is accessed. */ int sqliteInit(sqlite *db, char **pzErrMsg){ int i, rc; if( db->init.busy ) return SQLITE_OK; assert( (db->flags & SQLITE_Initialized)==0 ); rc = SQLITE_OK; db->init.busy = 1; for(i=0; rc==SQLITE_OK && inDb; i++){ if( DbHasProperty(db, i, DB_SchemaLoaded) ) continue; assert( i!=1 ); /* Should have been initialized together with 0 */ rc = sqliteInitOne(db, i, pzErrMsg); if( rc ){ sqliteResetInternalSchema(db, i); } } db->init.busy = 0; if( rc==SQLITE_OK ){ db->flags |= SQLITE_Initialized; sqliteCommitInternalChanges(db); } /* If the database is in formats 1 or 2, then upgrade it to ** version 3. This will reconstruct all indices. If the ** upgrade fails for any reason (ex: out of disk space, database ** is read only, interrupt received, etc.) then fail the init. */ if( rc==SQLITE_OK && db->file_format<3 ){ char *zErr = 0; InitData initData; int meta[SQLITE_N_BTREE_META]; db->magic = SQLITE_MAGIC_OPEN; initData.db = db; initData.pzErrMsg = &zErr; db->file_format = 3; rc = sqlite_exec(db, "BEGIN; SELECT name FROM sqlite_master WHERE type='table';", upgrade_3_callback, &initData, &zErr); if( rc==SQLITE_OK ){ sqliteBtreeGetMeta(db->aDb[0].pBt, meta); meta[2] = 4; sqliteBtreeUpdateMeta(db->aDb[0].pBt, meta); sqlite_exec(db, "COMMIT", 0, 0, 0); } if( rc!=SQLITE_OK ){ sqliteSetString(pzErrMsg, "unable to upgrade database to the version 2.6 format", zErr ? ": " : 0, zErr, (char*)0); } sqlite_freemem(zErr); } if( rc!=SQLITE_OK ){ db->flags &= ~SQLITE_Initialized; } return rc; } /* ** The version of the library */ const char rcsid[] = "@(#) \044Id: SQLite version " SQLITE_VERSION " $"; const char sqlite_version[] = SQLITE_VERSION; /* ** Does the library expect data to be encoded as UTF-8 or iso8859? The ** following global constant always lets us know. */ #ifdef SQLITE_UTF8 const char sqlite_encoding[] = "UTF-8"; #else const char sqlite_encoding[] = "iso8859"; #endif /* ** Open a new SQLite database. Construct an "sqlite" structure to define ** the state of this database and return a pointer to that structure. ** ** An attempt is made to initialize the in-memory data structures that ** hold the database schema. But if this fails (because the schema file ** is locked) then that step is deferred until the first call to ** sqlite_exec(). */ sqlite *sqlite_open(const char *zFilename, int mode, char **pzErrMsg){ sqlite *db; int rc, i; /* Allocate the sqlite data structure */ db = sqliteMalloc( sizeof(sqlite) ); if( pzErrMsg ) *pzErrMsg = 0; if( db==0 ) goto no_mem_on_open; db->onError = OE_Default; db->priorNewRowid = 0; db->magic = SQLITE_MAGIC_BUSY; db->nDb = 2; db->aDb = db->aDbStatic; /* db->flags |= SQLITE_ShortColNames; */ sqliteHashInit(&db->aFunc, SQLITE_HASH_STRING, 1); for(i=0; inDb; i++){ sqliteHashInit(&db->aDb[i].tblHash, SQLITE_HASH_STRING, 0); sqliteHashInit(&db->aDb[i].idxHash, SQLITE_HASH_STRING, 0); sqliteHashInit(&db->aDb[i].trigHash, SQLITE_HASH_STRING, 0); sqliteHashInit(&db->aDb[i].aFKey, SQLITE_HASH_STRING, 1); } /* Open the backend database driver */ if( zFilename[0]==':' && strcmp(zFilename,":memory:")==0 ){ db->temp_store = 2; } rc = sqliteBtreeFactory(db, zFilename, 0, MAX_PAGES, &db->aDb[0].pBt); if( rc!=SQLITE_OK ){ switch( rc ){ default: { sqliteSetString(pzErrMsg, "unable to open database: ", zFilename, (char*)0); } } sqliteFree(db); sqliteStrRealloc(pzErrMsg); return 0; } db->aDb[0].zName = "main"; db->aDb[1].zName = "temp"; /* Attempt to read the schema */ sqliteRegisterBuiltinFunctions(db); rc = sqliteInit(db, pzErrMsg); db->magic = SQLITE_MAGIC_OPEN; if( sqlite_malloc_failed ){ sqlite_close(db); goto no_mem_on_open; }else if( rc!=SQLITE_OK && rc!=SQLITE_BUSY ){ sqlite_close(db); sqliteStrRealloc(pzErrMsg); return 0; }else if( pzErrMsg ){ sqliteFree(*pzErrMsg); *pzErrMsg = 0; } /* Return a pointer to the newly opened database structure */ return db; no_mem_on_open: sqliteSetString(pzErrMsg, "out of memory", (char*)0); sqliteStrRealloc(pzErrMsg); return 0; } /* ** Return the ROWID of the most recent insert */ int sqlite_last_insert_rowid(sqlite *db){ return db->lastRowid; } /* ** Return the number of changes in the most recent call to sqlite_exec(). */ int sqlite_changes(sqlite *db){ return db->nChange; } /* ** Return the number of changes produced by the last INSERT, UPDATE, or ** DELETE statement to complete execution. The count does not include ** changes due to SQL statements executed in trigger programs that were ** triggered by that statement */ int sqlite_last_statement_changes(sqlite *db){ return db->lsChange; } /* ** Close an existing SQLite database */ void sqlite_close(sqlite *db){ HashElem *i; int j; db->want_to_close = 1; if( sqliteSafetyCheck(db) || sqliteSafetyOn(db) ){ /* printf("DID NOT CLOSE\n"); fflush(stdout); */ return; } db->magic = SQLITE_MAGIC_CLOSED; for(j=0; jnDb; j++){ struct Db *pDb = &db->aDb[j]; if( pDb->pBt ){ sqliteBtreeClose(pDb->pBt); pDb->pBt = 0; } } sqliteResetInternalSchema(db, 0); assert( db->nDb<=2 ); assert( db->aDb==db->aDbStatic ); for(i=sqliteHashFirst(&db->aFunc); i; i=sqliteHashNext(i)){ FuncDef *pFunc, *pNext; for(pFunc = (FuncDef*)sqliteHashData(i); pFunc; pFunc=pNext){ pNext = pFunc->pNext; sqliteFree(pFunc); } } sqliteHashClear(&db->aFunc); sqliteFree(db); } /* ** Rollback all database files. */ void sqliteRollbackAll(sqlite *db){ int i; for(i=0; inDb; i++){ if( db->aDb[i].pBt ){ sqliteBtreeRollback(db->aDb[i].pBt); db->aDb[i].inTrans = 0; } } sqliteResetInternalSchema(db, 0); /* sqliteRollbackInternalChanges(db); */ } /* ** Execute SQL code. Return one of the SQLITE_ success/failure ** codes. Also write an error message into memory obtained from ** malloc() and make *pzErrMsg point to that message. ** ** If the SQL is a query, then for each row in the query result ** the xCallback() function is called. pArg becomes the first ** argument to xCallback(). If xCallback=NULL then no callback ** is invoked, even for queries. */ int sqlite_exec( sqlite *db, /* The database on which the SQL executes */ const char *zSql, /* The SQL to be executed */ sqlite_callback xCallback, /* Invoke this callback routine */ void *pArg, /* First argument to xCallback() */ char **pzErrMsg /* Write error messages here */ ){ int rc = SQLITE_OK; const char *zLeftover; sqlite_vm *pVm; int nRetry = 0; int nChange = 0; int nCallback; if( zSql==0 ) return SQLITE_OK; while( rc==SQLITE_OK && zSql[0] ){ pVm = 0; rc = sqlite_compile(db, zSql, &zLeftover, &pVm, pzErrMsg); if( rc!=SQLITE_OK ){ assert( pVm==0 || sqlite_malloc_failed ); return rc; } if( pVm==0 ){ /* This happens if the zSql input contained only whitespace */ break; } db->nChange += nChange; nCallback = 0; while(1){ int nArg; char **azArg, **azCol; rc = sqlite_step(pVm, &nArg, (const char***)&azArg,(const char***)&azCol); if( rc==SQLITE_ROW ){ if( xCallback!=0 && xCallback(pArg, nArg, azArg, azCol) ){ sqlite_finalize(pVm, 0); return SQLITE_ABORT; } nCallback++; }else{ if( rc==SQLITE_DONE && nCallback==0 && (db->flags & SQLITE_NullCallback)!=0 && xCallback!=0 ){ xCallback(pArg, nArg, azArg, azCol); } rc = sqlite_finalize(pVm, pzErrMsg); if( rc==SQLITE_SCHEMA && nRetry<2 ){ nRetry++; rc = SQLITE_OK; break; } if( db->pVdbe==0 ){ nChange = db->nChange; } nRetry = 0; zSql = zLeftover; while( isspace(zSql[0]) ) zSql++; break; } } } return rc; } /* ** Compile a single statement of SQL into a virtual machine. Return one ** of the SQLITE_ success/failure codes. Also write an error message into ** memory obtained from malloc() and make *pzErrMsg point to that message. */ int sqlite_compile( sqlite *db, /* The database on which the SQL executes */ const char *zSql, /* The SQL to be executed */ const char **pzTail, /* OUT: Next statement after the first */ sqlite_vm **ppVm, /* OUT: The virtual machine */ char **pzErrMsg /* OUT: Write error messages here */ ){ Parse sParse; if( pzErrMsg ) *pzErrMsg = 0; if( sqliteSafetyOn(db) ) goto exec_misuse; if( !db->init.busy ){ if( (db->flags & SQLITE_Initialized)==0 ){ int rc, cnt = 1; while( (rc = sqliteInit(db, pzErrMsg))==SQLITE_BUSY && db->xBusyCallback && db->xBusyCallback(db->pBusyArg, "", cnt++)!=0 ){} if( rc!=SQLITE_OK ){ sqliteStrRealloc(pzErrMsg); sqliteSafetyOff(db); return rc; } if( pzErrMsg ){ sqliteFree(*pzErrMsg); *pzErrMsg = 0; } } if( db->file_format<3 ){ sqliteSafetyOff(db); sqliteSetString(pzErrMsg, "obsolete database file format", (char*)0); return SQLITE_ERROR; } } assert( (db->flags & SQLITE_Initialized)!=0 || db->init.busy ); if( db->pVdbe==0 ){ db->nChange = 0; } memset(&sParse, 0, sizeof(sParse)); sParse.db = db; if( db->xTrace ) db->xTrace(db->pTraceArg, zSql); sqliteRunParser(&sParse, zSql, pzErrMsg); if( sqlite_malloc_failed ){ sqliteSetString(pzErrMsg, "out of memory", (char*)0); sParse.rc = SQLITE_NOMEM; sqliteRollbackAll(db); sqliteResetInternalSchema(db, 0); db->flags &= ~SQLITE_InTrans; } if( sParse.rc==SQLITE_DONE ) sParse.rc = SQLITE_OK; if( sParse.rc!=SQLITE_OK && pzErrMsg && *pzErrMsg==0 ){ sqliteSetString(pzErrMsg, sqlite_error_string(sParse.rc), (char*)0); } sqliteStrRealloc(pzErrMsg); if( sParse.rc==SQLITE_SCHEMA ){ sqliteResetInternalSchema(db, 0); } assert( ppVm ); *ppVm = (sqlite_vm*)sParse.pVdbe; if( pzTail ) *pzTail = sParse.zTail; if( sqliteSafetyOff(db) ) goto exec_misuse; return sParse.rc; exec_misuse: if( pzErrMsg ){ *pzErrMsg = 0; sqliteSetString(pzErrMsg, sqlite_error_string(SQLITE_MISUSE), (char*)0); sqliteStrRealloc(pzErrMsg); } return SQLITE_MISUSE; } /* ** The following routine destroys a virtual machine that is created by ** the sqlite_compile() routine. ** ** The integer returned is an SQLITE_ success/failure code that describes ** the result of executing the virtual machine. An error message is ** written into memory obtained from malloc and *pzErrMsg is made to ** point to that error if pzErrMsg is not NULL. The calling routine ** should use sqlite_freemem() to delete the message when it has finished ** with it. */ int sqlite_finalize( sqlite_vm *pVm, /* The virtual machine to be destroyed */ char **pzErrMsg /* OUT: Write error messages here */ ){ int rc = sqliteVdbeFinalize((Vdbe*)pVm, pzErrMsg); sqliteStrRealloc(pzErrMsg); return rc; } /* ** Terminate the current execution of a virtual machine then ** reset the virtual machine back to its starting state so that it ** can be reused. Any error message resulting from the prior execution ** is written into *pzErrMsg. A success code from the prior execution ** is returned. */ int sqlite_reset( sqlite_vm *pVm, /* The virtual machine to be destroyed */ char **pzErrMsg /* OUT: Write error messages here */ ){ int rc = sqliteVdbeReset((Vdbe*)pVm, pzErrMsg); sqliteVdbeMakeReady((Vdbe*)pVm, -1, 0); sqliteStrRealloc(pzErrMsg); return rc; } /* ** Return a static string that describes the kind of error specified in the ** argument. */ const char *sqlite_error_string(int rc){ const char *z; switch( rc ){ case SQLITE_OK: z = "not an error"; break; case SQLITE_ERROR: z = "SQL logic error or missing database"; break; case SQLITE_INTERNAL: z = "internal SQLite implementation flaw"; break; case SQLITE_PERM: z = "access permission denied"; break; case SQLITE_ABORT: z = "callback requested query abort"; break; case SQLITE_BUSY: z = "database is locked"; break; case SQLITE_LOCKED: z = "database table is locked"; break; case SQLITE_NOMEM: z = "out of memory"; break; case SQLITE_READONLY: z = "attempt to write a readonly database"; break; case SQLITE_INTERRUPT: z = "interrupted"; break; case SQLITE_IOERR: z = "disk I/O error"; break; case SQLITE_CORRUPT: z = "database disk image is malformed"; break; case SQLITE_NOTFOUND: z = "table or record not found"; break; case SQLITE_FULL: z = "database is full"; break; case SQLITE_CANTOPEN: z = "unable to open database file"; break; case SQLITE_PROTOCOL: z = "database locking protocol failure"; break; case SQLITE_EMPTY: z = "table contains no data"; break; case SQLITE_SCHEMA: z = "database schema has changed"; break; case SQLITE_TOOBIG: z = "too much data for one table row"; break; case SQLITE_CONSTRAINT: z = "constraint failed"; break; case SQLITE_MISMATCH: z = "datatype mismatch"; break; case SQLITE_MISUSE: z = "library routine called out of sequence";break; case SQLITE_NOLFS: z = "kernel lacks large file support"; break; case SQLITE_AUTH: z = "authorization denied"; break; case SQLITE_FORMAT: z = "auxiliary database format error"; break; case SQLITE_RANGE: z = "bind index out of range"; break; case SQLITE_NOTADB: z = "file is encrypted or is not a database";break; default: z = "unknown error"; break; } return z; } /* ** This routine implements a busy callback that sleeps and tries ** again until a timeout value is reached. The timeout value is ** an integer number of milliseconds passed in as the first ** argument. */ static int sqliteDefaultBusyCallback( void *Timeout, /* Maximum amount of time to wait */ const char *NotUsed, /* The name of the table that is busy */ int count /* Number of times table has been busy */ ){ #if SQLITE_MIN_SLEEP_MS==1 static const char delays[] = { 1, 2, 5, 10, 15, 20, 25, 25, 25, 50, 50, 50, 100}; static const short int totals[] = { 0, 1, 3, 8, 18, 33, 53, 78, 103, 128, 178, 228, 287}; # define NDELAY (sizeof(delays)/sizeof(delays[0])) int timeout = (int)Timeout; int delay, prior; if( count <= NDELAY ){ delay = delays[count-1]; prior = totals[count-1]; }else{ delay = delays[NDELAY-1]; prior = totals[NDELAY-1] + delay*(count-NDELAY-1); } if( prior + delay > timeout ){ delay = timeout - prior; if( delay<=0 ) return 0; } sqliteOsSleep(delay); return 1; #else int timeout = (int)Timeout; if( (count+1)*1000 > timeout ){ return 0; } sqliteOsSleep(1000); return 1; #endif } /* ** This routine sets the busy callback for an Sqlite database to the ** given callback function with the given argument. */ void sqlite_busy_handler( sqlite *db, int (*xBusy)(void*,const char*,int), void *pArg ){ db->xBusyCallback = xBusy; db->pBusyArg = pArg; } #ifndef SQLITE_OMIT_PROGRESS_CALLBACK /* ** This routine sets the progress callback for an Sqlite database to the ** given callback function with the given argument. The progress callback will ** be invoked every nOps opcodes. */ void sqlite_progress_handler( sqlite *db, int nOps, int (*xProgress)(void*), void *pArg ){ if( nOps>0 ){ db->xProgress = xProgress; db->nProgressOps = nOps; db->pProgressArg = pArg; }else{ db->xProgress = 0; db->nProgressOps = 0; db->pProgressArg = 0; } } #endif /* ** This routine installs a default busy handler that waits for the ** specified number of milliseconds before returning 0. */ void sqlite_busy_timeout(sqlite *db, int ms){ if( ms>0 ){ sqlite_busy_handler(db, sqliteDefaultBusyCallback, (void*)ms); }else{ sqlite_busy_handler(db, 0, 0); } } /* ** Cause any pending operation to stop at its earliest opportunity. */ void sqlite_interrupt(sqlite *db){ db->flags |= SQLITE_Interrupt; } /* ** 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. ** ** Note that we need to call free() not sqliteFree() here, since every ** string that is exported from SQLite should have already passed through ** sqliteStrRealloc(). */ void sqlite_freemem(void *p){ free(p); } /* ** Windows systems need functions to call to return the sqlite_version ** and sqlite_encoding strings since they are unable to access constants ** within DLLs. */ const char *sqlite_libversion(void){ return sqlite_version; } const char *sqlite_libencoding(void){ return sqlite_encoding; } /* ** Create new user-defined functions. The sqlite_create_function() ** routine creates a regular function and sqlite_create_aggregate() ** creates an aggregate function. ** ** Passing a NULL xFunc argument or NULL xStep and xFinalize arguments ** disables the function. Calling sqlite_create_function() with the ** same name and number of arguments as a prior call to ** sqlite_create_aggregate() disables the prior call to ** sqlite_create_aggregate(), and vice versa. ** ** If nArg is -1 it means that this function will accept any number ** of arguments, including 0. The maximum allowed value of nArg is 127. */ int sqlite_create_function( sqlite *db, /* Add the function to this database connection */ const char *zName, /* Name of the function to add */ int nArg, /* Number of arguments */ void (*xFunc)(sqlite_func*,int,const char**), /* The implementation */ void *pUserData /* User data */ ){ FuncDef *p; int nName; if( db==0 || zName==0 || sqliteSafetyCheck(db) ) return 1; if( nArg<-1 || nArg>127 ) return 1; nName = strlen(zName); if( nName>255 ) return 1; p = sqliteFindFunction(db, zName, nName, nArg, 1); if( p==0 ) return 1; p->xFunc = xFunc; p->xStep = 0; p->xFinalize = 0; p->pUserData = pUserData; return 0; } int sqlite_create_aggregate( sqlite *db, /* Add the function to this database connection */ const char *zName, /* Name of the function to add */ int nArg, /* Number of arguments */ void (*xStep)(sqlite_func*,int,const char**), /* The step function */ void (*xFinalize)(sqlite_func*), /* The finalizer */ void *pUserData /* User data */ ){ FuncDef *p; int nName; if( db==0 || zName==0 || sqliteSafetyCheck(db) ) return 1; if( nArg<-1 || nArg>127 ) return 1; nName = strlen(zName); if( nName>255 ) return 1; p = sqliteFindFunction(db, zName, nName, nArg, 1); if( p==0 ) return 1; p->xFunc = 0; p->xStep = xStep; p->xFinalize = xFinalize; p->pUserData = pUserData; return 0; } /* ** Change the datatype for all functions with a given name. See the ** header comment for the prototype of this function in sqlite.h for ** additional information. */ int sqlite_function_type(sqlite *db, const char *zName, int dataType){ FuncDef *p = (FuncDef*)sqliteHashFind(&db->aFunc, zName, strlen(zName)); while( p ){ p->dataType = dataType; p = p->pNext; } return SQLITE_OK; } /* ** Register a trace function. The pArg from the previously registered trace ** is returned. ** ** A NULL trace function means that no tracing is executes. A non-NULL ** trace is a pointer to a function that is invoked at the start of each ** sqlite_exec(). */ void *sqlite_trace(sqlite *db, void (*xTrace)(void*,const char*), void *pArg){ void *pOld = db->pTraceArg; db->xTrace = xTrace; db->pTraceArg = pArg; return pOld; } /*** EXPERIMENTAL *** ** ** Register a function to be invoked when a transaction comments. ** If either function returns non-zero, then the commit becomes a ** rollback. */ void *sqlite_commit_hook( sqlite *db, /* Attach the hook to this database */ int (*xCallback)(void*), /* Function to invoke on each commit */ void *pArg /* Argument to the function */ ){ void *pOld = db->pCommitArg; db->xCommitCallback = xCallback; db->pCommitArg = pArg; return pOld; } /* ** This routine is called to create a connection to a database BTree ** driver. If zFilename is the name of a file, then that file is ** opened and used. If zFilename is the magic name ":memory:" then ** the database is stored in memory (and is thus forgotten as soon as ** the connection is closed.) If zFilename is NULL then the database ** is for temporary use only and is deleted as soon as the connection ** is closed. ** ** A temporary database can be either a disk file (that is automatically ** deleted when the file is closed) or a set of red-black trees held in memory, ** depending on the values of the TEMP_STORE compile-time macro and the ** db->temp_store variable, according to the following chart: ** ** TEMP_STORE db->temp_store Location of temporary database ** ---------- -------------- ------------------------------ ** 0 any file ** 1 1 file ** 1 2 memory ** 1 0 file ** 2 1 file ** 2 2 memory ** 2 0 memory ** 3 any memory */ int sqliteBtreeFactory( const sqlite *db, /* Main database when opening aux otherwise 0 */ const char *zFilename, /* Name of the file containing the BTree database */ int omitJournal, /* if TRUE then do not journal this file */ int nCache, /* How many pages in the page cache */ Btree **ppBtree){ /* Pointer to new Btree object written here */ assert( ppBtree != 0); #ifndef SQLITE_OMIT_INMEMORYDB if( zFilename==0 ){ if (TEMP_STORE == 0) { /* Always use file based temporary DB */ return sqliteBtreeOpen(0, omitJournal, nCache, ppBtree); } else if (TEMP_STORE == 1 || TEMP_STORE == 2) { /* Switch depending on compile-time and/or runtime settings. */ int location = db->temp_store==0 ? TEMP_STORE : db->temp_store; if (location == 1) { return sqliteBtreeOpen(zFilename, omitJournal, nCache, ppBtree); } else { return sqliteRbtreeOpen(0, 0, 0, ppBtree); } } else { /* Always use in-core DB */ return sqliteRbtreeOpen(0, 0, 0, ppBtree); } }else if( zFilename[0]==':' && strcmp(zFilename,":memory:")==0 ){ return sqliteRbtreeOpen(0, 0, 0, ppBtree); }else #endif { return sqliteBtreeOpen(zFilename, omitJournal, nCache, ppBtree); } }