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 1.24 2008/03/21 18:01:14 drh Exp $ 18 */ 19 20 #include "sqliteInt.h" 21 #include <ctype.h> 22 23 /* 24 ** Execute SQL code. Return one of the SQLITE_ success/failure 25 ** codes. Also write an error message into memory obtained from 26 ** malloc() and make *pzErrMsg point to that message. 27 ** 28 ** If the SQL is a query, then for each row in the query result 29 ** the xCallback() function is called. pArg becomes the first 30 ** argument to xCallback(). If xCallback=NULL then no callback 31 ** is invoked, even for queries. 32 */ 33 int sqlite3_exec( 34 sqlite3 *db, /* The database on which the SQL executes */ 35 const char *zSql, /* The SQL to be executed */ 36 sqlite3_callback xCallback, /* Invoke this callback routine */ 37 void *pArg, /* First argument to xCallback() */ 38 char **pzErrMsg /* Write error messages here */ 39 ){ 40 int rc = SQLITE_OK; 41 const char *zLeftover; 42 sqlite3_stmt *pStmt = 0; 43 char **azCols = 0; 44 45 int nRetry = 0; 46 int nCallback; 47 48 if( zSql==0 ) return SQLITE_OK; 49 50 sqlite3_mutex_enter(db->mutex); 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 if( !azCols[i] ){ 87 db->mallocFailed = 1; 88 goto exec_out; 89 } 90 } 91 nCallback++; 92 } 93 if( rc==SQLITE_ROW ){ 94 azVals = &azCols[nCol]; 95 for(i=0; i<nCol; i++){ 96 azVals[i] = (char *)sqlite3_column_text(pStmt, i); 97 if( !azVals[i] && sqlite3_column_type(pStmt, i)!=SQLITE_NULL ){ 98 db->mallocFailed = 1; 99 goto exec_out; 100 } 101 } 102 } 103 if( xCallback(pArg, nCol, azVals, azCols) ){ 104 rc = SQLITE_ABORT; 105 goto exec_out; 106 } 107 } 108 109 if( rc!=SQLITE_ROW ){ 110 rc = sqlite3_finalize(pStmt); 111 pStmt = 0; 112 if( rc!=SQLITE_SCHEMA ){ 113 nRetry = 0; 114 zSql = zLeftover; 115 while( isspace((unsigned char)zSql[0]) ) zSql++; 116 } 117 break; 118 } 119 } 120 121 sqlite3_free(azCols); 122 azCols = 0; 123 } 124 125 exec_out: 126 if( pStmt ) sqlite3_finalize(pStmt); 127 if( azCols ) sqlite3_free(azCols); 128 129 rc = sqlite3ApiExit(db, rc); 130 if( rc!=SQLITE_OK && rc==sqlite3_errcode(db) && pzErrMsg ){ 131 int nErrMsg = 1 + strlen(sqlite3_errmsg(db)); 132 *pzErrMsg = sqlite3_malloc(nErrMsg); 133 if( *pzErrMsg ){ 134 memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg); 135 } 136 }else if( pzErrMsg ){ 137 *pzErrMsg = 0; 138 } 139 140 assert( (rc&db->errMask)==rc ); 141 sqlite3_mutex_leave(db->mutex); 142 return rc; 143 } 144