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 ** $Id: legacy.c,v 1.31 2009/01/20 16:53:40 danielk1977 Exp $ 18 */ 19 20 #include "sqliteInt.h" 21 22 /* 23 ** Execute SQL code. Return one of the SQLITE_ success/failure 24 ** codes. Also write an error message into memory obtained from 25 ** malloc() and make *pzErrMsg point to that message. 26 ** 27 ** If the SQL is a query, then for each row in the query result 28 ** the xCallback() function is called. pArg becomes the first 29 ** argument to xCallback(). If xCallback=NULL then no callback 30 ** is invoked, even for queries. 31 */ 32 int sqlite3_exec( 33 sqlite3 *db, /* The database on which the SQL executes */ 34 const char *zSql, /* The SQL to be executed */ 35 sqlite3_callback xCallback, /* Invoke this callback routine */ 36 void *pArg, /* First argument to xCallback() */ 37 char **pzErrMsg /* Write error messages here */ 38 ){ 39 int rc = SQLITE_OK; 40 const char *zLeftover; 41 sqlite3_stmt *pStmt = 0; 42 char **azCols = 0; 43 44 int nRetry = 0; 45 int nCallback; 46 47 if( zSql==0 ) zSql = ""; 48 49 sqlite3_mutex_enter(db->mutex); 50 sqlite3Error(db, SQLITE_OK, 0); 51 while( (rc==SQLITE_OK || (rc==SQLITE_SCHEMA && (++nRetry)<2)) && zSql[0] ){ 52 int nCol; 53 char **azVals = 0; 54 55 pStmt = 0; 56 rc = sqlite3_prepare(db, zSql, -1, &pStmt, &zLeftover); 57 assert( rc==SQLITE_OK || pStmt==0 ); 58 if( rc!=SQLITE_OK ){ 59 continue; 60 } 61 if( !pStmt ){ 62 /* this happens for a comment or white-space */ 63 zSql = zLeftover; 64 continue; 65 } 66 67 nCallback = 0; 68 nCol = sqlite3_column_count(pStmt); 69 70 while( 1 ){ 71 int i; 72 rc = sqlite3_step(pStmt); 73 74 /* Invoke the callback function if required */ 75 if( xCallback && (SQLITE_ROW==rc || 76 (SQLITE_DONE==rc && !nCallback && db->flags&SQLITE_NullCallback)) ){ 77 if( 0==nCallback ){ 78 if( azCols==0 ){ 79 azCols = sqlite3DbMallocZero(db, 2*nCol*sizeof(const char*) + 1); 80 if( azCols==0 ){ 81 goto exec_out; 82 } 83 } 84 for(i=0; i<nCol; i++){ 85 azCols[i] = (char *)sqlite3_column_name(pStmt, i); 86 /* sqlite3VdbeSetColName() installs column names as UTF8 87 ** strings so there is no way for sqlite3_column_name() to fail. */ 88 assert( azCols[i]!=0 ); 89 } 90 nCallback++; 91 } 92 if( rc==SQLITE_ROW ){ 93 azVals = &azCols[nCol]; 94 for(i=0; i<nCol; i++){ 95 azVals[i] = (char *)sqlite3_column_text(pStmt, i); 96 if( !azVals[i] && sqlite3_column_type(pStmt, i)!=SQLITE_NULL ){ 97 db->mallocFailed = 1; 98 goto exec_out; 99 } 100 } 101 } 102 if( xCallback(pArg, nCol, azVals, azCols) ){ 103 rc = SQLITE_ABORT; 104 sqlite3_finalize(pStmt); 105 pStmt = 0; 106 sqlite3Error(db, SQLITE_ABORT, 0); 107 goto exec_out; 108 } 109 } 110 111 if( rc!=SQLITE_ROW ){ 112 rc = sqlite3_finalize(pStmt); 113 pStmt = 0; 114 if( rc!=SQLITE_SCHEMA ){ 115 nRetry = 0; 116 zSql = zLeftover; 117 while( sqlite3Isspace(zSql[0]) ) zSql++; 118 } 119 break; 120 } 121 } 122 123 sqlite3DbFree(db, azCols); 124 azCols = 0; 125 } 126 127 exec_out: 128 if( pStmt ) sqlite3_finalize(pStmt); 129 sqlite3DbFree(db, azCols); 130 131 rc = sqlite3ApiExit(db, rc); 132 if( rc!=SQLITE_OK && rc==sqlite3_errcode(db) && pzErrMsg ){ 133 int nErrMsg = 1 + sqlite3Strlen30(sqlite3_errmsg(db)); 134 *pzErrMsg = sqlite3Malloc(nErrMsg); 135 if( *pzErrMsg ){ 136 memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg); 137 } 138 }else if( pzErrMsg ){ 139 *pzErrMsg = 0; 140 } 141 142 assert( (rc&db->errMask)==rc ); 143 sqlite3_mutex_leave(db->mutex); 144 return rc; 145 } 146