SQLite

**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the implementation of the sqlite3_prepare()
** interface, and routines that contribute to loading the database schema
** from disk.
**
** $Id: prepare.c,v 1.116 2009/04/02 18:32:27 drh Exp $
*/
#include "sqliteInt.h"

/*
** Fill the InitData structure with an error message that indicates
** that the database is corrupt.
*/

  const char **pzTail       /* OUT: End of parsed string */
){
  Parse sParse;
  char *zErrMsg = 0;
  int rc = SQLITE_OK;
  int i;



  if( sqlite3SafetyOn(db) ) return SQLITE_MISUSE;


  assert( ppStmt && *ppStmt==0 );
  assert( !db->mallocFailed );
  assert( sqlite3_mutex_held(db->mutex) );

  /* Check to verify that it is possible to get a read lock on all
  ** database schemas.  The inability to get a read lock indicates that
  ** some other database connection is holding a write-lock, which in
  ** turn means that the other connection has made uncommitted changes

  const char *zSql,         /* UTF-8 encoded SQL statement. */
  int nBytes,               /* Length of zSql in bytes. */
  int saveSqlFlag,          /* True to copy SQL text into the sqlite3_stmt */
  sqlite3_stmt **ppStmt,    /* OUT: A pointer to the prepared statement */
  const char **pzTail       /* OUT: End of parsed string */
){
  int rc;
  assert( ppStmt!=0 );
  *ppStmt = 0;
  if( !sqlite3SafetyCheckOk(db) ){
    return SQLITE_MISUSE;
  }
  sqlite3_mutex_enter(db->mutex);
  sqlite3BtreeEnterAll(db);
  rc = sqlite3Prepare(db, zSql, nBytes, saveSqlFlag, ppStmt, pzTail);
  sqlite3BtreeLeaveAll(db);

  ** encoded string to UTF-8, then invoking sqlite3_prepare(). The
  ** tricky bit is figuring out the pointer to return in *pzTail.
  */
  char *zSql8;
  const char *zTail8 = 0;
  int rc = SQLITE_OK;

  assert( ppStmt );
  *ppStmt = 0;
  if( !sqlite3SafetyCheckOk(db) ){
    return SQLITE_MISUSE;
  }
  sqlite3_mutex_enter(db->mutex);
  zSql8 = sqlite3Utf16to8(db, zSql, nBytes);
  if( zSql8 ){

** 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 1.437 2009/04/02 18:32:27 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++.

** CAPI3REF: Compiling An SQL Statement {H13010} <S10000>
** KEYWORDS: {SQL statement compiler}
**
** To execute an SQL query, it must first be compiled into a byte-code
** program using one of these routines.
**
** The first argument, "db", is a [database connection] obtained from a
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or
** [sqlite3_open16()].  The database connection must not have been closed.
**
** The second argument, "zSql", is the statement to be compiled, encoded
** as either UTF-8 or UTF-16.  The sqlite3_prepare() and sqlite3_prepare_v2()
** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()
** use UTF-16.
**
** If the nByte argument is less than zero, then zSql is read up to the
** first zero terminator. If nByte is non-negative, then it is the maximum
** number of  bytes read from zSql.  When nByte is non-negative, the
** zSql string ends at either the first '\000' or '\u0000' character or
** the nByte-th byte, whichever comes first. If the caller knows
** that the supplied string is nul-terminated, then there is a small
** performance advantage to be gained by passing an nByte parameter that
** is equal to the number of bytes in the input string <i>including</i>
** the nul-terminator bytes.
**
** If pzTail is not NULL then *pzTail is made to point to the first byte
** past the end of the first SQL statement in zSql.  These routines only
** compile the first statement in zSql, so *pzTail is left pointing to
** what remains uncompiled.
**
** *ppStmt is left pointing to a compiled [prepared statement] that can be
** executed using [sqlite3_step()].  If there is an error, *ppStmt is set
** to NULL.  If the input text contains no SQL (if the input is an empty
** string or a comment) then *ppStmt is set to NULL.
** The calling procedure is responsible for deleting the compiled
** SQL statement using [sqlite3_finalize()] after it has finished with it.
** ppStmt may not be NULL.
**
** On success, [SQLITE_OK] is returned, otherwise an [error code] is returned.
**
** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are
** recommended for all new programs. The two older interfaces are retained
** for backwards compatibility, but their use is discouraged.
** In the "v2" interfaces, the prepared statement

**
*************************************************************************
**
** This file contains obscure tests of the C-interface required
** for completeness. Test code is written in C for these cases
** as there is not much point in binding to Tcl.
**
** $Id: test9.c,v 1.7 2009/04/02 18:32:27 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>

/*

  ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int objc,              /* Number of arguments */
  Tcl_Obj *CONST objv[]  /* Command arguments */
){
  const char *zErrFunction = "N/A";
  sqlite3 *db = 0;
  sqlite3_stmt *pStmt;
  int rc;

  if( objc!=1 ){
    Tcl_WrongNumArgs(interp, 1, objv, "");
    return TCL_ERROR;
  }

  rc = sqlite3_errcode(db);
  if( rc!=SQLITE_MISUSE ){
    zErrFunction = "sqlite3_errcode";
    goto error_out;
  }

  pStmt = (sqlite3_stmt*)1234;
  rc = sqlite3_prepare(db, 0, 0, &pStmt, 0);
  if( rc!=SQLITE_MISUSE ){
    zErrFunction = "sqlite3_prepare";
    goto error_out;
  }
  assert( pStmt==0 ); /* Verify that pStmt is zeroed even on a MISUSE error */

  pStmt = (sqlite3_stmt*)1234;
  rc = sqlite3_prepare_v2(db, 0, 0, &pStmt, 0);
  if( rc!=SQLITE_MISUSE ){
    zErrFunction = "sqlite3_prepare_v2";
    goto error_out;
  }
  assert( pStmt==0 );

#ifndef SQLITE_OMIT_UTF16
  pStmt = (sqlite3_stmt*)1234;
  rc = sqlite3_prepare16(db, 0, 0, &pStmt, 0);
  if( rc!=SQLITE_MISUSE ){
    zErrFunction = "sqlite3_prepare16";
    goto error_out;
  }
  assert( pStmt==0 );
  pStmt = (sqlite3_stmt*)1234;
  rc = sqlite3_prepare16_v2(db, 0, 0, &pStmt, 0);
  if( rc!=SQLITE_MISUSE ){
    zErrFunction = "sqlite3_prepare16_v2";
    goto error_out;
  }
  assert( pStmt==0 );
#endif

  return TCL_OK;

error_out:
  Tcl_ResetResult(interp);
  Tcl_AppendResult(interp, "Error testing function: ", zErrFunction, 0);