SQLite

**
*************************************************************************
** 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: legacy.c,v 1.26 2008/05/20 15:44:31 drh Exp $
*/

#include "sqliteInt.h"
#include <ctype.h>

/*
** Execute SQL code.  Return one of the SQLITE_ success/failure

  const char *zLeftover;
  sqlite3_stmt *pStmt = 0;
  char **azCols = 0;

  int nRetry = 0;
  int nCallback;

  if( zSql==0 ) zSql = "";

  sqlite3_mutex_enter(db->mutex);
  sqlite3Error(db, SQLITE_OK, 0);
  while( (rc==SQLITE_OK || (rc==SQLITE_SCHEMA && (++nRetry)<2)) && zSql[0] ){
    int nCol;
    char **azVals = 0;

    pStmt = 0;
    rc = sqlite3_prepare(db, zSql, -1, &pStmt, &zLeftover);
    assert( rc==SQLITE_OK || pStmt==0 );

** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
** @(#) $Id: sqlite.h.in,v 1.314 2008/05/20 15:44:31 drh Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.

** sqlite3_exec().  The statements are evaluated one by one
** until either an error or an interrupt is encountered or
** until they are all done.  The 3rd parameter is an optional
** callback that is invoked once for each row of any query results
** produced by the SQL statements.  The 5th parameter tells where
** to write any error messages.
**
** The error message passed back through the 5th parameter is held
** in memory obtained from [sqlite3_malloc()].  To avoid a memory leak,
** the calling application should call [sqlite3_free()] on any error
** message returned through the 5th parameter when it has finished using
** the error message.
**
** If the SQL statement in the 2nd parameter is NULL or an empty string
** or a string containing only whitespace and comments, then SQL
** statements are evaluated and the database is unchanged.
**
** The sqlite3_exec() interface is implemented in terms of
** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].
** The sqlite3_exec() routine does nothing to the database that cannot be done
** by [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()].

**
** INVARIANTS:
** 
** {F12101} A successful invocation of [sqlite3_exec(D,S,C,A,E)]
**          shall evaluate all of the UTF-8 encoded, semicolon-separated,
**          SQL statements in the zero-terminated string S within the
**          context of the D [database connection].
**
** {F12102} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is NULL then
**          the actions of the interface shall be the same as if the
**          S parameter where an empty string.
**
** {F12104} The return value of [sqlite3_exec()] shall be SQLITE_OK if all
**          SQL statements run successfully and to completion.
**
** {F12105} The return value of [sqlite3_exec()] shall be an appropriate 
**          non-zero [error code] if any SQL statement fails.
**
** {F12107} If one or more of the SQL statements handed to [sqlite3_exec()]
**          return results and the 3rd parameter is not NULL, then
**          the callback function specified by the 3rd parameter shall be
**          invoked once for each row of result.
**
** {F12110} If the callback returns a non-zero value then [sqlite3_exec()]
**          shall aborted the SQL statement it is currently evaluating,
**          skip all subsequent SQL statements, and return [SQLITE_ABORT].
**




** {F12113} The [sqlite3_exec()] routine shall pass its 4th parameter through
**          as the 1st parameter of the callback.
**
** {F12116} The [sqlite3_exec()] routine sets the 2nd parameter of its
**          callback to be the number of columns in the current row of
**          result.
**
** {F12119} The [sqlite3_exec()] routine sets the 3rd parameter of its 
**          callback to be an array of pointers to strings holding the
**          values for each column in the current result set row as
**          obtained from [sqlite3_column_text()].
**
** {F12122} The [sqlite3_exec()] routine sets the 4th parameter of its
**          callback to be an array of pointers to strings holding the
**          names of result columns as obtained from [sqlite3_column_name()].
**
** {F12125} If the 3rd parameter to [sqlite3_exec()] is NULL then
**          [sqlite3_exec()] never invokes a callback.  All query
**          results are silently discarded.
**




** {F12131} If an error occurs while parsing or evaluating any of the SQL
**          handed in the S parameter of [sqlite3_exec(D,S,C,A,E)] and if
**          the E parameter is not NULL, then [sqlite3_exec()] shall store
**          in *E an appropriate error message written into memory obtained
**          from [sqlite3_malloc()].
**
** {F12134} The [sqlite3_exec(D,S,C,A,E)] routine shall set the value of
**          *E to NULL if E is not NULL and there are no errors.
**
** {F12137} The [sqlite3_exec(D,S,C,A,E)] function shall set the error code
**          and message accessible via [sqlite3_errcode()],
**          [sqlite3_errmsg()], and [sqlite3_errmsg16()].
**
** {F12138} If the S parameter to [sqlite3_exec(D,S,C,A,E)] is a null or empty
**          string or contains nothing other than whitespace, comments, and/or
**          semicolons, then results of [sqlite3_errcode()],
**          [sqlite3_errmsg()], and [sqlite3_errmsg16()]
**          shall reset to indicate no errors.
**
** LIMITATIONS:
**
** {U12141} The first parameter to [sqlite3_exec()] must be an valid and open
**          [database connection].
**
** {U12142} The database connection must not be closed while
**          [sqlite3_exec()] is running.
** 
** {U12143} The calling function should use [sqlite3_free()] to free
**          the memory that *errmsg is left pointing at once the error
**          message is no longer needed.
**
** {U12145} The SQL statement text in the 2nd parameter to [sqlite3_exec()]
**          must remain unchanged while [sqlite3_exec()] is running.
*/
int sqlite3_exec(