sl@0: /*
sl@0: ** 2001 September 15
sl@0: **
sl@0: ** The author disclaims copyright to this source code.  In place of
sl@0: ** a legal notice, here is a blessing:
sl@0: **
sl@0: **    May you do good and not evil.
sl@0: **    May you find forgiveness for yourself and forgive others.
sl@0: **    May you share freely, never taking more than you give.
sl@0: **
sl@0: *************************************************************************
sl@0: ** Main file for the SQLite library.  The routines in this file
sl@0: ** implement the programmer interface to the library.  Routines in
sl@0: ** other files are for internal use by SQLite and should not be
sl@0: ** accessed by users of the library.
sl@0: **
sl@0: ** $Id: legacy.c,v 1.29 2008/08/02 03:50:39 drh Exp $
sl@0: */
sl@0: 
sl@0: #include "sqliteInt.h"
sl@0: #include <ctype.h>
sl@0: 
sl@0: /*
sl@0: ** Execute SQL code.  Return one of the SQLITE_ success/failure
sl@0: ** codes.  Also write an error message into memory obtained from
sl@0: ** malloc() and make *pzErrMsg point to that message.
sl@0: **
sl@0: ** If the SQL is a query, then for each row in the query result
sl@0: ** the xCallback() function is called.  pArg becomes the first
sl@0: ** argument to xCallback().  If xCallback=NULL then no callback
sl@0: ** is invoked, even for queries.
sl@0: */
sl@0: int sqlite3_exec(
sl@0:   sqlite3 *db,                /* The database on which the SQL executes */
sl@0:   const char *zSql,           /* The SQL to be executed */
sl@0:   sqlite3_callback xCallback, /* Invoke this callback routine */
sl@0:   void *pArg,                 /* First argument to xCallback() */
sl@0:   char **pzErrMsg             /* Write error messages here */
sl@0: ){
sl@0:   int rc = SQLITE_OK;
sl@0:   const char *zLeftover;
sl@0:   sqlite3_stmt *pStmt = 0;
sl@0:   char **azCols = 0;
sl@0: 
sl@0:   int nRetry = 0;
sl@0:   int nCallback;
sl@0: 
sl@0:   if( zSql==0 ) zSql = "";
sl@0: 
sl@0:   sqlite3_mutex_enter(db->mutex);
sl@0:   sqlite3Error(db, SQLITE_OK, 0);
sl@0:   while( (rc==SQLITE_OK || (rc==SQLITE_SCHEMA && (++nRetry)<2)) && zSql[0] ){
sl@0:     int nCol;
sl@0:     char **azVals = 0;
sl@0: 
sl@0:     pStmt = 0;
sl@0:     rc = sqlite3_prepare(db, zSql, -1, &pStmt, &zLeftover);
sl@0:     assert( rc==SQLITE_OK || pStmt==0 );
sl@0:     if( rc!=SQLITE_OK ){
sl@0:       continue;
sl@0:     }
sl@0:     if( !pStmt ){
sl@0:       /* this happens for a comment or white-space */
sl@0:       zSql = zLeftover;
sl@0:       continue;
sl@0:     }
sl@0: 
sl@0:     nCallback = 0;
sl@0:     nCol = sqlite3_column_count(pStmt);
sl@0: 
sl@0:     while( 1 ){
sl@0:       int i;
sl@0:       rc = sqlite3_step(pStmt);
sl@0: 
sl@0:       /* Invoke the callback function if required */
sl@0:       if( xCallback && (SQLITE_ROW==rc || 
sl@0:           (SQLITE_DONE==rc && !nCallback && db->flags&SQLITE_NullCallback)) ){
sl@0:         if( 0==nCallback ){
sl@0:           if( azCols==0 ){
sl@0:             azCols = sqlite3DbMallocZero(db, 2*nCol*sizeof(const char*) + 1);
sl@0:             if( azCols==0 ){
sl@0:               goto exec_out;
sl@0:             }
sl@0:           }
sl@0:           for(i=0; i<nCol; i++){
sl@0:             azCols[i] = (char *)sqlite3_column_name(pStmt, i);
sl@0:             /* sqlite3VdbeSetColName() installs column names as UTF8
sl@0:             ** strings so there is no way for sqlite3_column_name() to fail. */
sl@0:             assert( azCols[i]!=0 );
sl@0:           }
sl@0:           nCallback++;
sl@0:         }
sl@0:         if( rc==SQLITE_ROW ){
sl@0:           azVals = &azCols[nCol];
sl@0:           for(i=0; i<nCol; i++){
sl@0:             azVals[i] = (char *)sqlite3_column_text(pStmt, i);
sl@0:             if( !azVals[i] && sqlite3_column_type(pStmt, i)!=SQLITE_NULL ){
sl@0:               db->mallocFailed = 1;
sl@0:               goto exec_out;
sl@0:             }
sl@0:           }
sl@0:         }
sl@0:         if( xCallback(pArg, nCol, azVals, azCols) ){
sl@0:           rc = SQLITE_ABORT;
sl@0:           sqlite3_finalize(pStmt);
sl@0:           pStmt = 0;
sl@0:           sqlite3Error(db, SQLITE_ABORT, 0);
sl@0:           goto exec_out;
sl@0:         }
sl@0:       }
sl@0: 
sl@0:       if( rc!=SQLITE_ROW ){
sl@0:         rc = sqlite3_finalize(pStmt);
sl@0:         pStmt = 0;
sl@0:         if( rc!=SQLITE_SCHEMA ){
sl@0:           nRetry = 0;
sl@0:           zSql = zLeftover;
sl@0:           while( isspace((unsigned char)zSql[0]) ) zSql++;
sl@0:         }
sl@0:         break;
sl@0:       }
sl@0:     }
sl@0: 
sl@0:     sqlite3DbFree(db, azCols);
sl@0:     azCols = 0;
sl@0:   }
sl@0: 
sl@0: exec_out:
sl@0:   if( pStmt ) sqlite3_finalize(pStmt);
sl@0:   sqlite3DbFree(db, azCols);
sl@0: 
sl@0:   rc = sqlite3ApiExit(db, rc);
sl@0:   if( rc!=SQLITE_OK && rc==sqlite3_errcode(db) && pzErrMsg ){
sl@0:     int nErrMsg = 1 + strlen(sqlite3_errmsg(db));
sl@0:     *pzErrMsg = sqlite3Malloc(nErrMsg);
sl@0:     if( *pzErrMsg ){
sl@0:       memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg);
sl@0:     }
sl@0:   }else if( pzErrMsg ){
sl@0:     *pzErrMsg = 0;
sl@0:   }
sl@0: 
sl@0:   assert( (rc&db->errMask)==rc );
sl@0:   sqlite3_mutex_leave(db->mutex);
sl@0:   return rc;
sl@0: }