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 1.29 2006/01/25 22:50:38 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** Fill the InitData structure with an error message that indicates

  **    meta[4]   Db text encoding. 1:UTF-8 3:UTF-16 LE 4:UTF-16 BE
  **    meta[5]   The user cookie. Used by the application.
  **    meta[6]   
  **    meta[7]
  **    meta[8]
  **    meta[9]
  **
  ** Note: The #defined SQLITE_UTF* symbols in sqliteInt.h correspond to
  ** the possible values of meta[4].
  */
  if( rc==SQLITE_OK ){
    int i;
    for(i=0; rc==SQLITE_OK && i<sizeof(meta)/sizeof(meta[0]); i++){
      rc = sqlite3BtreeGetMeta(pDb->pBt, i+1, (u32 *)&meta[i]);
    }

    sqlite3DeleteTable(0, pTab);
  }
  sqlite3HashClear(&temp1);
  pSchema->pSeqTab = 0;
  pSchema->flags &= ~DB_SchemaLoaded;
}

/*
** Find and return the schema associated with a BTree.  Create
** a new one if necessary.
*/
Schema *sqlite3SchemaGet(Btree *pBt){
  Schema * p;
  if( pBt ){
    p = (Schema *)sqlite3BtreeSchema(pBt,sizeof(Schema),sqlite3SchemaFree);
  }else{
    p = (Schema *)sqliteMalloc(sizeof(Schema));
  }
  if( p && 0==p->file_format ){
    sqlite3HashInit(&p->tblHash, SQLITE_HASH_STRING, 0);
    sqlite3HashInit(&p->idxHash, SQLITE_HASH_STRING, 0);
    sqlite3HashInit(&p->trigHash, SQLITE_HASH_STRING, 0);
    sqlite3HashInit(&p->aFKey, SQLITE_HASH_STRING, 1);
  }
  return p;
}

/*
** Convert a schema pointer into the iDb index that indicates
** which database file in db->aDb[] the schema refers to.
**
** If the same database is attached more than once, the first
** attached database is returned.
*/
int sqlite3SchemaToIndex(sqlite3 *db, Schema *pSchema){
  int i = -1000000;

  /* If pSchema is NULL, then return -1000000. This happens when code in 
  ** expr.c is trying to resolve a reference to a transient table (i.e. one
  ** created by a sub-select). In this case the return value of this 
  ** function should never be used.

  int i;
  VdbeOp *pOp;

  i = p->nOp;
  p->nOp++;
  assert( p->magic==VDBE_MAGIC_INIT );
  resizeOpArray(p, i+1);
  assert( p->aOp==0 || p->nOpAlloc>=i+1 );
  if( p->aOp==0 ){
    return 0;
  }
  pOp = &p->aOp[i];
  pOp->opcode = op;
  pOp->p1 = p1;
  pOp->p2 = p2;
  pOp->p3 = 0;