**
*************************************************************************
** This file contains code used to implement the sqlite3_set_authorizer()
** API.  This facility is an optional feature of the library.  Embedded
** systems that do not need this facility may omit it by recompiling
** the library with -DSQLITE_OMIT_AUTHORIZATION=1
**
** $Id: auth.c,v 1.30 2009/05/04 01:58:31 drh Exp $
*/
#include "sqliteInt.h"

/*
** All of the code in this file may be omitted by defining a single
** macro.
*/
................................................................................
  assert( pExpr->op==TK_COLUMN );
  iDb = sqlite3SchemaToIndex(pParse->db, pSchema);
  if( iDb<0 ){
    /* An attempt to read a column out of a subquery or other
    ** temporary table. */
    return;
  }
  for(iSrc=0; pTabList && iSrc<pTabList->nSrc; iSrc++){

    if( pExpr->iTable==pTabList->a[iSrc].iCursor ) break;
  }
  if( pTabList && iSrc<pTabList->nSrc ){
    pTab = pTabList->a[iSrc].pTab;

  }else if( (pStack = pParse->trigStack)!=0 ){

    /* This must be an attempt to read the NEW or OLD pseudo-tables
    ** of a trigger.
    */
    assert( pExpr->iTable==pStack->newIdx || pExpr->iTable==pStack->oldIdx );
    pTab = pStack->pTab;
  }
  if( pTab==0 ) return;


  if( pExpr->iColumn>=0 ){
    assert( pExpr->iColumn<pTab->nCol );
    zCol = pTab->aCol[pExpr->iColumn].zName;
  }else if( pTab->iPKey>=0 ){
    assert( pTab->iPKey<pTab->nCol );
    zCol = pTab->aCol[pTab->iPKey].zName;
  }else{
................................................................................
** popped.  Or if pParse==0, this routine is a no-op.
*/
void sqlite3AuthContextPush(
  Parse *pParse,
  AuthContext *pContext, 
  const char *zContext
){

  pContext->pParse = pParse;
  if( pParse ){
    pContext->zAuthContext = pParse->zAuthContext;
    pParse->zAuthContext = zContext;
  }
}

/*
** Pop an authorization context that was previously pushed
** by sqlite3AuthContextPush
*/
void sqlite3AuthContextPop(AuthContext *pContext){

**
*************************************************************************
** This file contains code used to implement the sqlite3_set_authorizer()
** API.  This facility is an optional feature of the library.  Embedded
** systems that do not need this facility may omit it by recompiling
** the library with -DSQLITE_OMIT_AUTHORIZATION=1
**
** $Id: auth.c,v 1.31 2009/05/04 18:01:40 drh Exp $
*/
#include "sqliteInt.h"

/*
** All of the code in this file may be omitted by defining a single
** macro.
*/
................................................................................
  assert( pExpr->op==TK_COLUMN );
  iDb = sqlite3SchemaToIndex(pParse->db, pSchema);
  if( iDb<0 ){
    /* An attempt to read a column out of a subquery or other
    ** temporary table. */
    return;
  }
  if( pTabList ){
    for(iSrc=0; ALWAYS(iSrc<pTabList->nSrc); iSrc++){
      if( pExpr->iTable==pTabList->a[iSrc].iCursor ) break;
    }
    assert( iSrc<pTabList->nSrc );
    pTab = pTabList->a[iSrc].pTab;
  }else{
    pStack = pParse->trigStack;
    if( ALWAYS(pStack) ){
      /* This must be an attempt to read the NEW or OLD pseudo-tables
      ** of a trigger.
      */
      assert( pExpr->iTable==pStack->newIdx || pExpr->iTable==pStack->oldIdx );
      pTab = pStack->pTab;
    }

  }
  if( NEVER(pTab==0) ) return;
  if( pExpr->iColumn>=0 ){
    assert( pExpr->iColumn<pTab->nCol );
    zCol = pTab->aCol[pExpr->iColumn].zName;
  }else if( pTab->iPKey>=0 ){
    assert( pTab->iPKey<pTab->nCol );
    zCol = pTab->aCol[pTab->iPKey].zName;
  }else{
................................................................................
** popped.  Or if pParse==0, this routine is a no-op.
*/
void sqlite3AuthContextPush(
  Parse *pParse,
  AuthContext *pContext, 
  const char *zContext
){
  assert( pParse );
  pContext->pParse = pParse;

  pContext->zAuthContext = pParse->zAuthContext;
  pParse->zAuthContext = zContext;

}

/*
** Pop an authorization context that was previously pushed
** by sqlite3AuthContextPush
*/
void sqlite3AuthContextPop(AuthContext *pContext){