1 /* 2 ** 2001 September 15 3 ** 4 ** The author disclaims copyright to this source code. In place of 5 ** a legal notice, here is a blessing: 6 ** 7 ** May you do good and not evil. 8 ** May you find forgiveness for yourself and forgive others. 9 ** May you share freely, never taking more than you give. 10 ** 11 ************************************************************************* 12 ** Main file for the SQLite library. The routines in this file 13 ** implement the programmer interface to the library. Routines in 14 ** other files are for internal use by SQLite and should not be 15 ** accessed by users of the library. 16 */ 17 18 #include "sqliteInt.h" 19 20 /* 21 ** Execute SQL code. Return one of the SQLITE_ success/failure 22 ** codes. Also write an error message into memory obtained from 23 ** malloc() and make *pzErrMsg point to that message. 24 ** 25 ** If the SQL is a query, then for each row in the query result 26 ** the xCallback() function is called. pArg becomes the first 27 ** argument to xCallback(). If xCallback=NULL then no callback 28 ** is invoked, even for queries. 29 */ 30 int sqlite3_exec( 31 sqlite3 *db, /* The database on which the SQL executes */ 32 const char *zSql, /* The SQL to be executed */ 33 sqlite3_callback xCallback, /* Invoke this callback routine */ 34 void *pArg, /* First argument to xCallback() */ 35 char **pzErrMsg /* Write error messages here */ 36 ){ 37 int rc = SQLITE_OK; /* Return code */ 38 const char *zLeftover; /* Tail of unprocessed SQL */ 39 sqlite3_stmt *pStmt = 0; /* The current SQL statement */ 40 char **azCols = 0; /* Names of result columns */ 41 int callbackIsInit; /* True if callback data is initialized */ 42 43 if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT; 44 if( zSql==0 ) zSql = ""; 45 46 sqlite3_mutex_enter(db->mutex); 47 sqlite3Error(db, SQLITE_OK); 48 while( rc==SQLITE_OK && zSql[0] ){ 49 int nCol; 50 char **azVals = 0; 51 52 pStmt = 0; 53 rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, &zLeftover); 54 assert( rc==SQLITE_OK || pStmt==0 ); 55 if( rc!=SQLITE_OK ){ 56 continue; 57 } 58 if( !pStmt ){ 59 /* this happens for a comment or white-space */ 60 zSql = zLeftover; 61 continue; 62 } 63 64 callbackIsInit = 0; 65 nCol = sqlite3_column_count(pStmt); 66 67 while( 1 ){ 68 int i; 69 rc = sqlite3_step(pStmt); 70 71 /* Invoke the callback function if required */ 72 if( xCallback && (SQLITE_ROW==rc || 73 (SQLITE_DONE==rc && !callbackIsInit 74 && db->flags&SQLITE_NullCallback)) ){ 75 if( !callbackIsInit ){ 76 azCols = sqlite3DbMallocRaw(db, (2*nCol+1)*sizeof(const char*)); 77 if( azCols==0 ){ 78 goto exec_out; 79 } 80 for(i=0; i<nCol; i++){ 81 azCols[i] = (char *)sqlite3_column_name(pStmt, i); 82 /* sqlite3VdbeSetColName() installs column names as UTF8 83 ** strings so there is no way for sqlite3_column_name() to fail. */ 84 assert( azCols[i]!=0 ); 85 } 86 callbackIsInit = 1; 87 } 88 if( rc==SQLITE_ROW ){ 89 azVals = &azCols[nCol]; 90 for(i=0; i<nCol; i++){ 91 azVals[i] = (char *)sqlite3_column_text(pStmt, i); 92 if( !azVals[i] && sqlite3_column_type(pStmt, i)!=SQLITE_NULL ){ 93 sqlite3OomFault(db); 94 goto exec_out; 95 } 96 } 97 azVals[i] = 0; 98 } 99 if( xCallback(pArg, nCol, azVals, azCols) ){ 100 /* EVIDENCE-OF: R-38229-40159 If the callback function to 101 ** sqlite3_exec() returns non-zero, then sqlite3_exec() will 102 ** return SQLITE_ABORT. */ 103 rc = SQLITE_ABORT; 104 sqlite3VdbeFinalize((Vdbe *)pStmt); 105 pStmt = 0; 106 sqlite3Error(db, SQLITE_ABORT); 107 goto exec_out; 108 } 109 } 110 111 if( rc!=SQLITE_ROW ){ 112 rc = sqlite3VdbeFinalize((Vdbe *)pStmt); 113 pStmt = 0; 114 zSql = zLeftover; 115 while( sqlite3Isspace(zSql[0]) ) zSql++; 116 break; 117 } 118 } 119 120 sqlite3DbFree(db, azCols); 121 azCols = 0; 122 } 123 124 exec_out: 125 if( pStmt ) sqlite3VdbeFinalize((Vdbe *)pStmt); 126 sqlite3DbFree(db, azCols); 127 128 rc = sqlite3ApiExit(db, rc); 129 if( rc!=SQLITE_OK && pzErrMsg ){ 130 *pzErrMsg = sqlite3DbStrDup(0, sqlite3_errmsg(db)); 131 if( *pzErrMsg==0 ){ 132 rc = SQLITE_NOMEM_BKPT; 133 sqlite3Error(db, SQLITE_NOMEM); 134 } 135 }else if( pzErrMsg ){ 136 *pzErrMsg = 0; 137 } 138 139 assert( (rc&db->errMask)==rc ); 140 sqlite3_mutex_leave(db->mutex); 141 return rc; 142 } 143