Unnamed Fossil Project

	touch .target_source

sqlite3.c:	.target_source $(TOP)/tool/mksqlite3c.tcl
	$(TCLSH_CMD) $(TOP)/tool/mksqlite3c.tcl

# Rules to build the LEMON compiler generator
#
lemon$(BEXE):	$(TOP)/tool/lemon.c $(TOP)/src/lempar.c
	$(BCC) -o $@ $(TOP)/tool/lemon.c
	cp $(TOP)/src/lempar.c .


# Rule to build the amalgamation
#
sqlite3.lo:	sqlite3.c
	$(LTCOMPILE) $(TEMP_STORE) -c sqlite3.c

	tclsh $(TOP)/ext/fts2/mkfts2amal.tcl

fts3amal.c:	target_source $(TOP)/ext/fts3/mkfts3amal.tcl
	tclsh $(TOP)/ext/fts3/mkfts3amal.tcl

# Rules to build the LEMON compiler generator
#
lemon:	$(TOP)/tool/lemon.c $(TOP)/src/lempar.c
	$(BCC) -o lemon $(TOP)/tool/lemon.c
	cp $(TOP)/src/lempar.c .

# Rules to build individual *.o files from generated *.c files. This
# applies to:
#
#     parse.o
#     opcodes.o
#

3.6.16

#! /bin/sh
# Guess values for system-dependent variables and create Makefiles.
# Generated by GNU Autoconf 2.62 for sqlite 3.6.16.
#
# Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
# 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
# This configure script is free software; the Free Software Foundation
# gives unlimited permission to copy, distribute and modify it.
## --------------------- ##
## M4sh Initialization.  ##

MFLAGS=
MAKEFLAGS=
SHELL=${CONFIG_SHELL-/bin/sh}

# Identity of this package.
PACKAGE_NAME='sqlite'
PACKAGE_TARNAME='sqlite'
PACKAGE_VERSION='3.6.16'
PACKAGE_STRING='sqlite 3.6.16'
PACKAGE_BUGREPORT=''

# Factoring default headers for most tests.
ac_includes_default="\
#include <stdio.h>
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>

#
# Report the --help message.
#
if test "$ac_init_help" = "long"; then
  # Omit some internal or obsolete options to make the list less imposing.
  # This message is too long to be a string in the A/UX 3.1 sh.
  cat <<_ACEOF
\`configure' configures sqlite 3.6.16 to adapt to many kinds of systems.

Usage: $0 [OPTION]... [VAR=VALUE]...

To assign environment variables (e.g., CC, CFLAGS...), specify them as
VAR=VALUE.  See below for descriptions of some of the useful variables.

Defaults for the options are specified in brackets.

  --build=BUILD     configure for building on BUILD [guessed]
  --host=HOST       cross-compile to build programs to run on HOST [BUILD]
_ACEOF
fi

if test -n "$ac_init_help"; then
  case $ac_init_help in
     short | recursive ) echo "Configuration of sqlite 3.6.16:";;
   esac
  cat <<\_ACEOF

Optional Features:
  --disable-option-checking  ignore unrecognized --enable/--with options
  --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
  --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]

    cd "$ac_pwd" || { ac_status=$?; break; }
  done
fi

test -n "$ac_init_help" && exit $ac_status
if $ac_init_version; then
  cat <<\_ACEOF
sqlite configure 3.6.16
generated by GNU Autoconf 2.62

Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
This configure script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it.
_ACEOF
  exit
fi
cat >config.log <<_ACEOF
This file contains any messages produced by compilers while
running configure, to aid debugging if configure makes a mistake.

It was created by sqlite $as_me 3.6.16, which was
generated by GNU Autoconf 2.62.  Invocation command line was

  $ $0 $@

_ACEOF
exec 5>>config.log
{

 configure \$PACKAGE_VERSION = $PACKAGE_VERSION
 top level VERSION file     = $sqlite_version_sanity_check
please regen with autoconf" >&2;}
   { (exit 1); exit 1; }; }
fi

# The following RCS revision string applies to configure.in
# $Revision: 1.73 $

#########
# Programs needed
#
case `pwd` in
  *\ * | *\	*)
    { $as_echo "$as_me:$LINENO: WARNING: Libtool does not cope well with whitespace in \`pwd\`" >&5

exec 6>&1

# Save the log message, to keep $[0] and so on meaningful, and to
# report actual input values of CONFIG_FILES etc. instead of their
# values after options handling.
ac_log="
This file was extended by sqlite $as_me 3.6.16, which was
generated by GNU Autoconf 2.62.  Invocation command line was

  CONFIG_FILES    = $CONFIG_FILES
  CONFIG_HEADERS  = $CONFIG_HEADERS
  CONFIG_LINKS    = $CONFIG_LINKS
  CONFIG_COMMANDS = $CONFIG_COMMANDS
  $ $0 $@

$config_commands

Report bugs to <bug-autoconf@gnu.org>."

_ACEOF
cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
ac_cs_version="\\
sqlite config.status 3.6.16
configured by $0, generated by GNU Autoconf 2.62,
  with options \\"`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`\\"

Copyright (C) 2008 Free Software Foundation, Inc.
This config.status script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it."

	tclsh $(TOP)/ext/fts2/mkfts2amal.tcl

fts3amal.c:	target_source $(TOP)/ext/fts3/mkfts3amal.tcl
	tclsh $(TOP)/ext/fts3/mkfts3amal.tcl

# Rules to build the LEMON compiler generator
#
lemon:	$(TOP)/tool/lemon.c $(TOP)/src/lempar.c
	$(BCC) -o lemon $(TOP)/tool/lemon.c
	cp $(TOP)/src/lempar.c .

# Rules to build individual *.o files from generated *.c files. This
# applies to:
#
#     parse.o
#     opcodes.o
#

**
*************************************************************************
** 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 1.32 2009/07/02 18:40:35 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** All of the code in this file may be omitted by defining a single
** macro.
*/

){
  sqlite3 *db = pParse->db;
  int rc;
  Table *pTab = 0;      /* The table being read */
  const char *zCol;     /* Name of the column of the table */
  int iSrc;             /* Index in pTabList->a[] of table being read */
  const char *zDBase;   /* Name of database being accessed */

  int iDb;              /* The index of the database the expression refers to */

  if( db->xAuth==0 ) return;
  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; iSrc<pTabList->nSrc; iSrc++){
      if( pExpr->iTable==pTabList->a[iSrc].iCursor ){
        pTab = pTabList->a[iSrc].pTab;
	break;
      }

    }
  }
  if( !pTab ){

    TriggerStack *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 );

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the implementation of the sqlite3_backup_XXX() 
** API functions and the related features.
**
** $Id: backup.c,v 1.19 2009/07/06 19:03:13 drh Exp $
*/
#include "sqliteInt.h"
#include "btreeInt.h"

/* Macro to find the minimum of two numeric values.
*/
#ifndef MIN

    }

    /* Lock the destination database, if it is not locked already. */
    if( SQLITE_OK==rc && p->bDestLocked==0
     && SQLITE_OK==(rc = sqlite3BtreeBeginTrans(p->pDest, 2)) 
    ){
      p->bDestLocked = 1;
      sqlite3BtreeGetMeta(p->pDest, BTREE_SCHEMA_VERSION, &p->iDestSchema);
    }

    /* If there is no open read-transaction on the source database, open
    ** one now. If a transaction is opened here, then it will be closed
    ** before this function exits.
    */
    if( rc==SQLITE_OK && 0==sqlite3BtreeIsInReadTrans(p->pSrc) ){

      if( p->iNext>(Pgno)nSrcPage ){
        rc = SQLITE_DONE;
      }else if( !p->isAttached ){
        attachBackupObject(p);
      }
    }
  
    /* Update the schema version field in the destination database. This
    ** is to make sure that the schema-version really does change in
    ** the case where the source and destination databases have the
    ** same schema version.
    */
    if( rc==SQLITE_DONE 
     && (rc = sqlite3BtreeUpdateMeta(p->pDest,1,p->iDestSchema+1))==SQLITE_OK
    ){
      const int nSrcPagesize = sqlite3BtreeGetPageSize(p->pSrc);
      const int nDestPagesize = sqlite3BtreeGetPageSize(p->pDest);
      int nDestTruncate;
  






      if( p->pDestDb ){
        sqlite3ResetInternalSchema(p->pDestDb, 0);
      }

      /* Set nDestTruncate to the final number of pages in the destination
      ** database. The complication here is that the destination page
      ** size may be different to the source page size. 

/*
** 2004 April 6
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** $Id: btree.c,v 1.653 2009/07/06 18:56:13 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/
#include "btreeInt.h"

int sqlite3_enable_shared_cache(int enable){
  sqlite3GlobalConfig.sharedCacheEnabled = enable;
  return SQLITE_OK;
}
#endif








#ifdef SQLITE_OMIT_SHARED_CACHE
  /*
  ** The functions querySharedCacheTableLock(), setSharedCacheTableLock(),
  ** and clearAllSharedCacheTableLocks()
  ** manipulate entries in the BtShared.pLock linked list used to store
  ** shared-cache table level locks. If the library is compiled with the
  ** shared-cache feature disabled, then there is only ever one user
  ** of each BtShared structure and so this locking is not necessary. 
  ** So define the lock related functions as no-ops.
  */
  #define querySharedCacheTableLock(a,b,c) SQLITE_OK
  #define setSharedCacheTableLock(a,b,c) SQLITE_OK
  #define clearAllSharedCacheTableLocks(a)
  #define downgradeAllSharedCacheTableLocks(a)
  #define hasSharedCacheTableLock(a,b,c,d) 1
  #define hasReadConflicts(a, b) 0
#endif

#ifndef SQLITE_OMIT_SHARED_CACHE

#ifdef SQLITE_DEBUG
/*
** This function is only used as part of an assert() statement. It checks
** that connection p holds the required locks to read or write to the 
** b-tree with root page iRoot. If so, true is returned. Otherwise, false. 
** For example, when writing to a table b-tree with root-page iRoot via 
** Btree connection pBtree:
**
**    assert( hasSharedCacheTableLock(pBtree, iRoot, 0, WRITE_LOCK) );
**
** When writing to an index b-tree that resides in a sharable database, the 
** caller should have first obtained a lock specifying the root page of
** the corresponding table b-tree. This makes things a bit more complicated,
** as this module treats each b-tree as a separate structure. To determine
** the table b-tree corresponding to the index b-tree being written, this
** function has to search through the database schema.
**
** Instead of a lock on the b-tree rooted at page iRoot, the caller may
** hold a write-lock on the schema table (root page 1). This is also
** acceptable.
*/
static int hasSharedCacheTableLock(
  Btree *pBtree,         /* Handle that must hold lock */
  Pgno iRoot,            /* Root page of b-tree */
  int isIndex,           /* True if iRoot is the root of an index b-tree */
  int eLockType          /* Required lock type (READ_LOCK or WRITE_LOCK) */
){
  Schema *pSchema = (Schema *)pBtree->pBt->pSchema;
  Pgno iTab = 0;
  BtLock *pLock;

  /* If this b-tree database is not shareable, or if the client is reading
  ** and has the read-uncommitted flag set, then no lock is required. 
  ** In these cases return true immediately.  If the client is reading 
  ** or writing an index b-tree, but the schema is not loaded, then return
  ** true also. In this case the lock is required, but it is too difficult
  ** to check if the client actually holds it. This doesn't happen very
  ** often.  */
  if( (pBtree->sharable==0)
   || (eLockType==READ_LOCK && (pBtree->db->flags & SQLITE_ReadUncommitted))
   || (isIndex && (!pSchema || (pSchema->flags&DB_SchemaLoaded)==0 ))
  ){
    return 1;
  }

  /* Figure out the root-page that the lock should be held on. For table
  ** b-trees, this is just the root page of the b-tree being read or
  ** written. For index b-trees, it is the root page of the associated
  ** table.  */
  if( isIndex ){
    HashElem *p;
    for(p=sqliteHashFirst(&pSchema->idxHash); p; p=sqliteHashNext(p)){
      Index *pIdx = (Index *)sqliteHashData(p);
      if( pIdx->tnum==iRoot ){
	iTab = pIdx->pTable->tnum;
      }
    }
  }else{
    iTab = iRoot;
  }

  /* Search for the required lock. Either a write-lock on root-page iTab, a 
  ** write-lock on the schema table, or (if the client is reading) a
  ** read-lock on iTab will suffice. Return 1 if any of these are found.  */
  for(pLock=pBtree->pBt->pLock; pLock; pLock=pLock->pNext){
    if( pLock->pBtree==pBtree 
     && (pLock->iTable==iTab || (pLock->eLock==WRITE_LOCK && pLock->iTable==1))
     && pLock->eLock>=eLockType 
    ){
      return 1;
    }
  }

  /* Failed to find the required lock. */
  return 0;
}

/*
** This function is also used as part of assert() statements only. It 
** returns true if there exist one or more cursors open on the table 
** with root page iRoot that do not belong to either connection pBtree 
** or some other connection that has the read-uncommitted flag set.
**
** For example, before writing to page iRoot:
**
**    assert( !hasReadConflicts(pBtree, iRoot) );
*/
static int hasReadConflicts(Btree *pBtree, Pgno iRoot){
  BtCursor *p;
  for(p=pBtree->pBt->pCursor; p; p=p->pNext){
    if( p->pgnoRoot==iRoot 
     && p->pBtree!=pBtree
     && 0==(p->pBtree->db->flags & SQLITE_ReadUncommitted)
    ){
      return 1;
    }
  }
  return 0;
}
#endif    /* #ifdef SQLITE_DEBUG */

/*
** Query to see if btree handle p may obtain a lock of type eLock 
** (READ_LOCK or WRITE_LOCK) on the table with root-page iTab. Return
** SQLITE_OK if the lock may be obtained (by calling
** setSharedCacheTableLock()), or SQLITE_LOCKED if not.
*/
static int querySharedCacheTableLock(Btree *p, Pgno iTab, u8 eLock){
  BtShared *pBt = p->pBt;
  BtLock *pIter;

  assert( sqlite3BtreeHoldsMutex(p) );
  assert( eLock==READ_LOCK || eLock==WRITE_LOCK );
  assert( p->db!=0 );
  assert( !(p->db->flags&SQLITE_ReadUncommitted)||eLock==WRITE_LOCK||iTab==1 );
  
  /* If requesting a write-lock, then the Btree must have an open write
  ** transaction on this file. And, obviously, for this to be so there 
  ** must be an open write transaction on the file itself.
  */
  assert( eLock==READ_LOCK || (p==pBt->pWriter && p->inTrans==TRANS_WRITE) );
  assert( eLock==READ_LOCK || pBt->inTransaction==TRANS_WRITE );

  ** requested lock may not be obtained.
  */
  if( pBt->pWriter!=p && pBt->isExclusive ){
    sqlite3ConnectionBlocked(p->db, pBt->pWriter->db);
    return SQLITE_LOCKED_SHAREDCACHE;
  }






















  for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
    /* The condition (pIter->eLock!=eLock) in the following if(...) 
    ** statement is a simplification of:
    **
    **   (eLock==WRITE_LOCK || pIter->eLock==WRITE_LOCK)
    **
    ** since we know that if eLock==WRITE_LOCK, then no other connection
    ** may hold a WRITE_LOCK on any table in this file (since there can
    ** only be a single writer).
    */
    assert( pIter->eLock==READ_LOCK || pIter->eLock==WRITE_LOCK );
    assert( eLock==READ_LOCK || pIter->pBtree==p || pIter->eLock==READ_LOCK);
    if( pIter->pBtree!=p && pIter->iTable==iTab && pIter->eLock!=eLock ){
      sqlite3ConnectionBlocked(p->db, pIter->pBtree->db);
      if( eLock==WRITE_LOCK ){
        assert( p==pBt->pWriter );
        pBt->isPending = 1;
      }
      return SQLITE_LOCKED_SHAREDCACHE;

    }
  }
  return SQLITE_OK;
}
#endif /* !SQLITE_OMIT_SHARED_CACHE */

#ifndef SQLITE_OMIT_SHARED_CACHE

  BtLock *pLock = 0;
  BtLock *pIter;

  assert( sqlite3BtreeHoldsMutex(p) );
  assert( eLock==READ_LOCK || eLock==WRITE_LOCK );
  assert( p->db!=0 );

  /* A connection with the read-uncommitted flag set will never try to
  ** obtain a read-lock using this function. The only read-lock obtained
  ** by a connection in read-uncommitted mode is on the sqlite_master 
  ** table, and that lock is obtained in BtreeBeginTrans().  */
  assert( 0==(p->db->flags&SQLITE_ReadUncommitted) || eLock==WRITE_LOCK );

  /* This is a no-op if the shared-cache is not enabled */
  if( !p->sharable ){
    return SQLITE_OK;
  }

  assert( SQLITE_OK==querySharedCacheTableLock(p, iTable, eLock) );















  /* First search the list for an existing lock on this table. */
  for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
    if( pIter->iTable==iTable && pIter->pBtree==p ){
      pLock = pIter;
      break;
    }
  }

  while( *ppIter ){
    BtLock *pLock = *ppIter;
    assert( pBt->isExclusive==0 || pBt->pWriter==pLock->pBtree );
    assert( pLock->pBtree->inTrans>=pLock->eLock );
    if( pLock->pBtree==p ){
      *ppIter = pLock->pNext;
      assert( pLock->iTable!=1 || pLock==&p->lock );
      if( pLock->iTable!=1 ){
        sqlite3_free(pLock);
      }
    }else{
      ppIter = &pLock->pNext;
    }
  }

  assert( pBt->isPending==0 || pBt->pWriter );
  if( pBt->pWriter==p ){

    **
    ** If there is not currently a writer, then BtShared.isPending must
    ** be zero already. So this next line is harmless in that case.
    */
    pBt->isPending = 0;
  }
}

/*
** This function changes all write-locks held by connection p to read-locks.
*/
static void downgradeAllSharedCacheTableLocks(Btree *p){
  BtShared *pBt = p->pBt;
  if( pBt->pWriter==p ){
    BtLock *pLock;
    pBt->pWriter = 0;
    pBt->isExclusive = 0;
    pBt->isPending = 0;
    for(pLock=pBt->pLock; pLock; pLock=pLock->pNext){
      assert( pLock->eLock==READ_LOCK || pLock->pBtree==p );
      pLock->eLock = READ_LOCK;
    }
  }
}

#endif /* SQLITE_OMIT_SHARED_CACHE */

static void releasePage(MemPage *pPage);  /* Forward reference */

/*
** Verify that the cursor holds a mutex on the BtShared
*/

static void invalidateAllOverflowCache(BtShared *pBt){
  BtCursor *p;
  assert( sqlite3_mutex_held(pBt->mutex) );
  for(p=pBt->pCursor; p; p=p->pNext){
    invalidateOverflowCache(p);
  }
}

/*
** This function is called before modifying the contents of a table
** b-tree to invalidate any incrblob cursors that are open on the
** row or one of the rows being modified. Argument pgnoRoot is the 
** root-page of the table b-tree. 
**
** If argument isClearTable is true, then the entire contents of the
** table is about to be deleted. In this case invalidate all incrblob
** cursors open on any row within the table with root-page pgnoRoot.
**
** Otherwise, if argument isClearTable is false, then the row with
** rowid iRow is being replaced or deleted. In this case invalidate
** only those incrblob cursors open on this specific row.
*/
static void invalidateIncrblobCursors(
  Btree *pBtree,          /* The database file to check */
  Pgno pgnoRoot,          /* Look for read cursors on this btree */
  i64 iRow,               /* The rowid that might be changing */
  int isClearTable        /* True if all rows are being deleted */
){
  BtCursor *p;
  BtShared *pBt = pBtree->pBt;
  assert( sqlite3BtreeHoldsMutex(pBtree) );
  for(p=pBt->pCursor; p; p=p->pNext){
    if( p->isIncrblobHandle && (isClearTable || p->info.nKey==iRow) ){
      p->eState = CURSOR_INVALID;
    }
  }
}

#else
  #define invalidateOverflowCache(x)
  #define invalidateAllOverflowCache(x)
  #define invalidateIncrblobCursors(w,x,y,z)
#endif

/*
** Set bit pgno of the BtShared.pHasContent bitvec. This is called 
** when a page that previously contained data becomes a free-list leaf 
** page.
**

*/
void sqlite3BtreeClearCursor(BtCursor *pCur){
  assert( cursorHoldsMutex(pCur) );
  sqlite3_free(pCur->pKey);
  pCur->pKey = 0;
  pCur->eState = CURSOR_INVALID;
}

/*
** In this version of BtreeMoveto, pKey is a packed index record
** such as is generated by the OP_MakeRecord opcode.  Unpack the
** record and then call BtreeMovetoUnpacked() to do the work.
*/
static int btreeMoveto(
  BtCursor *pCur,     /* Cursor open on the btree to be searched */
  const void *pKey,   /* Packed key if the btree is an index */
  i64 nKey,           /* Integer key for tables.  Size of pKey for indices */
  int bias,           /* Bias search to the high end */
  int *pRes           /* Write search results here */
){
  int rc;                    /* Status code */
  UnpackedRecord *pIdxKey;   /* Unpacked index key */
  char aSpace[150];          /* Temp space for pIdxKey - to avoid a malloc */

  if( pKey ){
    assert( nKey==(i64)(int)nKey );
    pIdxKey = sqlite3VdbeRecordUnpack(pCur->pKeyInfo, (int)nKey, pKey,
                                      aSpace, sizeof(aSpace));
    if( pIdxKey==0 ) return SQLITE_NOMEM;
  }else{
    pIdxKey = 0;
  }
  rc = sqlite3BtreeMovetoUnpacked(pCur, pIdxKey, nKey, bias, pRes);
  if( pKey ){
    sqlite3VdbeDeleteUnpackedRecord(pIdxKey);
  }
  return rc;
}

/*
** Restore the cursor to the position it was in (or as close to as possible)
** when saveCursorPosition() was called. Note that this call deletes the 
** saved position info stored by saveCursorPosition(), so there can be
** at most one effective restoreCursorPosition() call after each 
** saveCursorPosition().
*/
int sqlite3BtreeRestoreCursorPosition(BtCursor *pCur){
  int rc;
  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState>=CURSOR_REQUIRESEEK );
  if( pCur->eState==CURSOR_FAULT ){
    return pCur->skip;
  }
  pCur->eState = CURSOR_INVALID;
  rc = btreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &pCur->skip);
  if( rc==SQLITE_OK ){
    sqlite3_free(pCur->pKey);
    pCur->pKey = 0;
    assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
  }
  return rc;
}

  if( *pEType<1 || *pEType>5 ) return SQLITE_CORRUPT_BKPT;
  return SQLITE_OK;
}

#else /* if defined SQLITE_OMIT_AUTOVACUUM */
  #define ptrmapPut(w,x,y,z) SQLITE_OK
  #define ptrmapGet(w,x,y,z) SQLITE_OK
  #define ptrmapPutOvflPtr(x, y) SQLITE_OK
#endif

/*
** Given a btree page and a cell index (0 means the first cell on
** the page, 1 means the second cell, and so forth) return a pointer
** to the cell content.
**

  /* Assert that the space between the cell-offset array and the 
  ** cell-content area is greater than nByte bytes.
  */
  assert( nByte <= (
      get2byte(&data[hdr+5])-(hdr+8+(pPage->leaf?0:4)+2*get2byte(&data[hdr+3]))
  ));


  nFrag = data[hdr+7];
  if( nFrag>=60 ){
    defragmentPage(pPage);
  }else{
    /* Search the freelist looking for a free slot big enough to satisfy 
    ** the request. The allocation is made from the first free slot in 
    ** the list that is large enough to accomadate it.

  if ( pbegin>pPage->pBt->usableSize-4 ) {
    return SQLITE_CORRUPT_BKPT;
  }
  assert( pbegin>addr || pbegin==0 );
  put2byte(&data[addr], start);
  put2byte(&data[start], pbegin);
  put2byte(&data[start+2], size);
  pPage->nFree = pPage->nFree + (u16)size;

  /* Coalesce adjacent free blocks */
  addr = pPage->hdrOffset + 1;
  while( (pbegin = get2byte(&data[addr]))>0 ){
    int pnext, psize, x;
    assert( pbegin>addr );
    assert( pbegin<=pPage->pBt->usableSize-4 );

  pVfs = db->pVfs;
  p = sqlite3MallocZero(sizeof(Btree));
  if( !p ){
    return SQLITE_NOMEM;
  }
  p->inTrans = TRANS_NONE;
  p->db = db;
#ifndef SQLITE_OMIT_SHARED_CACHE
  p->lock.pBtree = p;
  p->lock.iTable = 1;
#endif

#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
  /*
  ** If this Btree is a candidate for shared cache, try to find an
  ** existing BtShared object that we can share with
  */
  if( isMemdb==0 && zFilename && zFilename[0] ){

page1_init_failed:
  releasePage(pPage1);
  pBt->pPage1 = 0;
  return rc;
}
























/*
** If there are no outstanding cursors and we are not in the middle
** of a transaction but there is a read lock on the database, then
** this routine unrefs the first page of the database file which 
** has the effect of releasing the read lock.
**


** If there is a transaction in progress, this routine is a no-op.
*/
static void unlockBtreeIfUnused(BtShared *pBt){
  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( pBt->pCursor==0 || pBt->inTransaction>TRANS_NONE );
  if( pBt->inTransaction==TRANS_NONE && pBt->pPage1!=0 ){
    assert( pBt->pPage1->aData );
    assert( sqlite3PagerRefcount(pBt->pPager)==1 );
    assert( pBt->pPage1->aData );
    releasePage(pBt->pPage1);

    pBt->pPage1 = 0;
  }
}

/*
** Create a new database by initializing the first page of the
** file.

  }
  if( pBlock ){
    sqlite3ConnectionBlocked(p->db, pBlock);
    rc = SQLITE_LOCKED_SHAREDCACHE;
    goto trans_begun;
  }
#endif

  /* Any read-only or read-write transaction implies a read-lock on 
  ** page 1. So if some other shared-cache client already has a write-lock 
  ** on page 1, the transaction cannot be opened. */
  if( SQLITE_OK!=(rc = querySharedCacheTableLock(p, MASTER_ROOT, READ_LOCK)) ){
    goto trans_begun;
  }

  do {
    /* Call lockBtree() until either pBt->pPage1 is populated or
    ** lockBtree() returns something other than SQLITE_OK. lockBtree()
    ** may return SQLITE_OK but leave pBt->pPage1 set to 0 if after
    ** reading page 1 it discovers that the page-size of the database 
    ** file is not pBt->pageSize. In this case lockBtree() will update

    }
  }while( rc==SQLITE_BUSY && pBt->inTransaction==TRANS_NONE &&
          btreeInvokeBusyHandler(pBt) );

  if( rc==SQLITE_OK ){
    if( p->inTrans==TRANS_NONE ){
      pBt->nTransaction++;
#ifndef SQLITE_OMIT_SHARED_CACHE
      if( p->sharable ){
	assert( p->lock.pBtree==p && p->lock.iTable==1 );
        p->lock.eLock = READ_LOCK;
        p->lock.pNext = pBt->pLock;
        pBt->pLock = &p->lock;
      }
#endif
    }
    p->inTrans = (wrflag?TRANS_WRITE:TRANS_READ);
    if( p->inTrans>pBt->inTransaction ){
      pBt->inTransaction = p->inTrans;
    }
#ifndef SQLITE_OMIT_SHARED_CACHE
    if( wrflag ){

    }
#endif
    rc = sqlite3PagerCommitPhaseOne(pBt->pPager, zMaster, 0);
    sqlite3BtreeLeave(p);
  }
  return rc;
}

/*
** This function is called from both BtreeCommitPhaseTwo() and BtreeRollback()
** at the conclusion of a transaction.
*/
static void btreeEndTransaction(Btree *p){
  BtShared *pBt = p->pBt;
  BtCursor *pCsr;
  assert( sqlite3BtreeHoldsMutex(p) );

  /* Search for a cursor held open by this b-tree connection. If one exists,
  ** then the transaction will be downgraded to a read-only transaction
  ** instead of actually concluded. A subsequent call to CommitPhaseTwo() 
  ** or Rollback() will finish the transaction and unlock the database.  */
  for(pCsr=pBt->pCursor; pCsr && pCsr->pBtree!=p; pCsr=pCsr->pNext);
  assert( pCsr==0 || p->inTrans>TRANS_NONE );

  btreeClearHasContent(pBt);
  if( pCsr ){
    downgradeAllSharedCacheTableLocks(p);
    p->inTrans = TRANS_READ;
  }else{
    /* If the handle had any kind of transaction open, decrement the 
    ** transaction count of the shared btree. If the transaction count 
    ** reaches 0, set the shared state to TRANS_NONE. The unlockBtreeIfUnused()
    ** call below will unlock the pager.  */
    if( p->inTrans!=TRANS_NONE ){
      clearAllSharedCacheTableLocks(p);
      pBt->nTransaction--;
      if( 0==pBt->nTransaction ){
        pBt->inTransaction = TRANS_NONE;
      }
    }

    /* Set the current transaction state to TRANS_NONE and unlock the 
    ** pager if this call closed the only read or write transaction.  */
    p->inTrans = TRANS_NONE;
    unlockBtreeIfUnused(pBt);
  }

  btreeIntegrity(p);
}

/*
** Commit the transaction currently in progress.
**
** This routine implements the second phase of a 2-phase commit.  The
** sqlite3BtreeCommitPhaseOne() routine does the first phase and should
** be invoked prior to calling this routine.  The sqlite3BtreeCommitPhaseOne()

    if( rc!=SQLITE_OK ){
      sqlite3BtreeLeave(p);
      return rc;
    }
    pBt->inTransaction = TRANS_READ;
  }








  btreeEndTransaction(p);













  sqlite3BtreeLeave(p);
  return SQLITE_OK;
}

/*
** Do both phases of a commit.
*/

    if( sqlite3BtreeGetPage(pBt, 1, &pPage1, 0)==SQLITE_OK ){
      releasePage(pPage1);
    }
    assert( countWriteCursors(pBt)==0 );
    pBt->inTransaction = TRANS_READ;
  }




  btreeEndTransaction(p);










  sqlite3BtreeLeave(p);
  return rc;
}

/*
** Start a statement subtransaction. The subtransaction can can be rolled
** back independently of the main transaction. You must start a transaction 

    sqlite3BtreeLeave(p);
  }
  return rc;
}

/*
** Create a new cursor for the BTree whose root is on the page
** iTable. If a read-only cursor is requested, it is assumed that
** the caller already has at least a read-only transaction open
** on the database already. If a write-cursor is requested, then
** the caller is assumed to have an open write transaction.
**
** If wrFlag==0, then the cursor can only be used for reading.
** If wrFlag==1, then the cursor can be used for reading or for
** writing if other conditions for writing are also met.  These
** are the conditions that must be met in order for writing to
** be allowed:
**

static int btreeCursor(
  Btree *p,                              /* The btree */
  int iTable,                            /* Root page of table to open */
  int wrFlag,                            /* 1 to write. 0 read-only */
  struct KeyInfo *pKeyInfo,              /* First arg to comparison function */
  BtCursor *pCur                         /* Space for new cursor */
){
  int rc;                                /* Return code */

  BtShared *pBt = p->pBt;                /* Shared b-tree handle */

  assert( sqlite3BtreeHoldsMutex(p) );
  assert( wrFlag==0 || wrFlag==1 );





  /* The following assert statements verify that if this is a sharable 
  ** b-tree database, the connection is holding the required table locks, 
  ** and that no other connection has any open cursor that conflicts with 
  ** this lock.  */
  assert( hasSharedCacheTableLock(p, iTable, pKeyInfo!=0, wrFlag+1) );
  assert( wrFlag==0 || !hasReadConflicts(p, iTable) );




  /* Assert that the caller has opened the required transaction. */
  assert( p->inTrans>TRANS_NONE );
  assert( wrFlag==0 || p->inTrans==TRANS_WRITE );
  assert( pBt->pPage1 && pBt->pPage1->aData );

  if( NEVER(wrFlag && pBt->readOnly) ){



    return SQLITE_READONLY;
  }


  if( iTable==1 && pagerPagecount(pBt)==0 ){

    return SQLITE_EMPTY;
  }




  pCur->pgnoRoot = (Pgno)iTable;
  rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->apPage[0]);
  if( rc!=SQLITE_OK ){
    assert( pCur->apPage[0]==0 );
    return rc;
  }

  /* Now that no other errors can occur, finish filling in the BtCursor
  ** variables and link the cursor into the BtShared list.  */


  pCur->pKeyInfo = pKeyInfo;
  pCur->pBtree = p;
  pCur->pBt = pBt;
  pCur->wrFlag = (u8)wrFlag;
  pCur->pNext = pBt->pCursor;
  if( pCur->pNext ){
    pCur->pNext->pPrev = pCur;
  }
  pBt->pCursor = pCur;
  pCur->eState = CURSOR_INVALID;
  pCur->cachedRowid = 0;

  return SQLITE_OK;





}
int sqlite3BtreeCursor(
  Btree *p,                                   /* The btree */
  int iTable,                                 /* Root page of table to open */
  int wrFlag,                                 /* 1 to write. 0 read-only */
  struct KeyInfo *pKeyInfo,                   /* First arg to xCompare() */
  BtCursor *pCur                              /* Write new cursor here */

    rc = moveToChild(pCur, chldPg);
    if( rc ) goto moveto_finish;
  }
moveto_finish:
  return rc;
}


































/*
** Return TRUE if the cursor is not pointing at an entry of the table.
**
** TRUE will be returned after a call to sqlite3BtreeNext() moves
** past the last entry in the table or sqlite3BtreePrev() moves past
** the first entry.  TRUE is also returned if the table is empty.

    idx = allocateSpace(pPage, sz);
    assert( idx>0 );
    assert( end <= get2byte(&data[hdr+5]) );
    if (idx+sz > pPage->pBt->usableSize) {
      return SQLITE_CORRUPT_BKPT;
    }
    pPage->nCell++;
    pPage->nFree = pPage->nFree - (u16)(2 + sz);
    memcpy(&data[idx+nSkip], pCell+nSkip, sz-nSkip);
    if( iChild ){
      put4byte(&data[idx], iChild);
    }
    for(j=end-2, ptr=&data[j]; j>ins; j-=2, ptr-=2){
      ptr[0] = ptr[-2];
      ptr[1] = ptr[-1];
    }
    put2byte(&data[ins], idx);
    put2byte(&data[hdr+3], pPage->nCell);
#ifndef SQLITE_OMIT_AUTOVACUUM
    if( pPage->pBt->autoVacuum ){
      /* The cell may contain a pointer to an overflow page. If so, write
      ** the entry for the overflow page into the pointer map.
      */
      return ptrmapPutOvflPtr(pPage, pCell);
    }
#endif
  }

  return SQLITE_OK;
}

      assert( n==pPage->pgno && e==PTRMAP_BTREE );
    }
  }
  return 1;
}
#endif

/*
** This function is used to copy the contents of the b-tree node stored 
** on page pFrom to page pTo. If page pFrom was not a leaf page, then
** the pointer-map entries for each child page are updated so that the
** parent page stored in the pointer map is page pTo. If pFrom contained
** any cells with overflow page pointers, then the corresponding pointer
** map entries are also updated so that the parent page is page pTo.
**
** If pFrom is currently carrying any overflow cells (entries in the
** MemPage.aOvfl[] array), they are not copied to pTo. 
**
** Before returning, page pTo is reinitialized using sqlite3BtreeInitPage().
**
** The performance of this function is not critical. It is only used by 
** the balance_shallower() and balance_deeper() procedures, neither of
** which are called often under normal circumstances.
*/
static int copyNodeContent(MemPage *pFrom, MemPage *pTo){
  BtShared * const pBt = pFrom->pBt;
  u8 * const aFrom = pFrom->aData;
  u8 * const aTo = pTo->aData;
  int const iFromHdr = pFrom->hdrOffset;
  int const iToHdr = ((pTo->pgno==1) ? 100 : 0);
  int rc = SQLITE_OK;
  int iData;

  assert( pFrom->isInit );
  assert( pFrom->nFree>=iToHdr );
  assert( get2byte(&aFrom[iFromHdr+5])<=pBt->usableSize );

  /* Copy the b-tree node content from page pFrom to page pTo. */
  iData = get2byte(&aFrom[iFromHdr+5]);
  memcpy(&aTo[iData], &aFrom[iData], pBt->usableSize-iData);
  memcpy(&aTo[iToHdr], &aFrom[iFromHdr], pFrom->cellOffset + 2*pFrom->nCell);

  /* Reinitialize page pTo so that the contents of the MemPage structure
  ** match the new data. The initialization of pTo "cannot" fail, as the
  ** data copied from pFrom is known to be valid.  */
  pTo->isInit = 0;
  TESTONLY(rc = ) sqlite3BtreeInitPage(pTo);
  assert( rc==SQLITE_OK );

  /* If this is an auto-vacuum database, update the pointer-map entries
  ** for any b-tree or overflow pages that pTo now contains the pointers to. */
  if( ISAUTOVACUUM ){
    rc = setChildPtrmaps(pTo);
  }
  return rc;
}

/*
** This routine redistributes cells on the iParentIdx'th child of pParent
** (hereafter "the page") and up to 2 siblings so that all pages have about the
** same amount of free space. Usually a single sibling on either side of the
** page are used in the balancing, though both siblings might come from one
** side if the page is the first or last child of its parent. If the page 

**
** If aOvflSpace is set to a null pointer, this function returns 
** SQLITE_NOMEM.
*/
static int balance_nonroot(
  MemPage *pParent,               /* Parent page of siblings being balanced */
  int iParentIdx,                 /* Index of "the page" in pParent */
  u8 *aOvflSpace,                 /* page-size bytes of space for parent ovfl */
  int isRoot                      /* True if pParent is a root-page */
){
  BtShared *pBt;               /* The whole database */
  int nCell = 0;               /* Number of cells in apCell[] */
  int nMaxCells = 0;           /* Allocated size of apCell, szCell, aFrom. */
  int nNew = 0;                /* Number of pages in apNew[] */
  int nOld;                    /* Number of pages in apOld[] */
  int i, j, k;                 /* Loop counters */
  int nxDiv;                   /* Next divider slot in pParent->aCell[] */
  int rc = SQLITE_OK;          /* The return code */
  u16 leafCorrection;          /* 4 if pPage is a leaf.  0 if not */
  int leafData;                /* True if pPage is a leaf of a LEAFDATA tree */
  int usableSpace;             /* Bytes in pPage beyond the header */
  int pageFlags;               /* Value of pPage->aData[0] */
  int subtotal;                /* Subtotal of bytes in cells on one page */
  int iSpace1 = 0;             /* First unused byte of aSpace1[] */
  int iOvflSpace = 0;          /* First unused byte of aOvflSpace[] */
  int szScratch;               /* Size of scratch memory requested */

    for(j=0; j<limit; j++){
      assert( nCell<nMaxCells );
      apCell[nCell] = findOverflowCell(pOld, j);
      szCell[nCell] = cellSizePtr(pOld, apCell[nCell]);
      nCell++;
    }
    if( i<nOld-1 && !leafData){
      u16 sz = (u16)szNew[i];
      u8 *pTemp;
      assert( nCell<nMaxCells );
      szCell[nCell] = sz;
      pTemp = &aSpace1[iSpace1];
      iSpace1 += sz;
      assert( sz<=pBt->pageSize/4 );
      assert( iSpace1<=pBt->pageSize );
      memcpy(pTemp, apDiv[i], sz);
      apCell[nCell] = pTemp+leafCorrection;
      assert( leafCorrection==0 || leafCorrection==4 );
      szCell[nCell] = szCell[nCell] - leafCorrection;
      if( !pOld->leaf ){
        assert( leafCorrection==0 );
        assert( pOld->hdrOffset==0 );
        /* The right pointer of the child page pOld becomes the left
        ** pointer of the divider cell */
        memcpy(apCell[nCell], &pOld->aData[8], 4);
      }else{

    assert( pNew->nOverflow==0 );

    j = cntNew[i];

    /* If the sibling page assembled above was not the right-most sibling,
    ** insert a divider cell into the parent page.
    */
    assert( i<nNew-1 || j==nCell );
    if( j<nCell ){
      u8 *pCell;
      u8 *pTemp;
      int sz;

      assert( j<nMaxCells );
      pCell = apCell[j];
      sz = szCell[j] + leafCorrection;

  assert( nOld>0 );
  assert( nNew>0 );
  if( (pageFlags & PTF_LEAF)==0 ){
    u8 *zChild = &apCopy[nOld-1]->aData[8];
    memcpy(&apNew[nNew-1]->aData[8], zChild, 4);
  }

  if( isRoot && pParent->nCell==0 && pParent->hdrOffset<=apNew[0]->nFree ){
    /* The root page of the b-tree now contains no cells. The only sibling
    ** page is the right-child of the parent. Copy the contents of the
    ** child page into the parent, decreasing the overall height of the
    ** b-tree structure by one. This is described as the "balance-shallower"
    ** sub-algorithm in some documentation.
    **
    ** If this is an auto-vacuum database, the call to copyNodeContent() 
    ** sets all pointer-map entries corresponding to database image pages 
    ** for which the pointer is stored within the content being copied.
    **
    ** The second assert below verifies that the child page is defragmented
    ** (it must be, as it was just reconstructed using assemblePage()). This
    ** is important if the parent page happens to be page 1 of the database
    ** image.  */
    assert( nNew==1 );
    assert( apNew[0]->nFree == 
        (get2byte(&apNew[0]->aData[5])-apNew[0]->cellOffset-apNew[0]->nCell*2) 
    );
    if( SQLITE_OK==(rc = copyNodeContent(apNew[0], pParent)) ){
      rc = freePage(apNew[0]);
    }
  }else if( ISAUTOVACUUM ){
    /* Fix the pointer-map entries for all the cells that were shifted around. 
    ** There are several different types of pointer-map entries that need to
    ** be dealt with by this routine. Some of these have been set already, but
    ** many have not. The following is a summary:
    **
    **   1) The entries associated with new sibling pages that were not
    **      siblings when this function was called. These have already
    **      been set. We don't need to worry about old siblings that were
    **      moved to the free-list - the freePage() code has taken care
    **      of those.
    **
    **   2) The pointer-map entries associated with the first overflow
    **      page in any overflow chains used by new divider cells. These 
    **      have also already been taken care of by the insertCell() code.
    **
    **   3) If the sibling pages are not leaves, then the child pages of
    **      cells stored on the sibling pages may need to be updated.
    **
    **   4) If the sibling pages are not internal intkey nodes, then any
    **      overflow pages used by these cells may need to be updated
    **      (internal intkey nodes never contain pointers to overflow pages).
    **
    **   5) If the sibling pages are not leaves, then the pointer-map
    **      entries for the right-child pages of each sibling may need
    **      to be updated.
    **
    ** Cases 1 and 2 are dealt with above by other code. The next
    ** block deals with cases 3 and 4 and the one after that, case 5. Since
    ** setting a pointer map entry is a relatively expensive operation, this
    ** code only sets pointer map entries for child or overflow pages that have
    ** actually moved between pages.  */

    MemPage *pNew = apNew[0];
    MemPage *pOld = apCopy[0];
    int nOverflow = pOld->nOverflow;
    int iNextOld = pOld->nCell + nOverflow;
    int iOverflow = (nOverflow ? pOld->aOvfl[0].idx : -1);
    j = 0;                             /* Current 'old' sibling page */
    k = 0;                             /* Current 'new' sibling page */

    ptrmapCheckPages(&pParent, 1);
#endif
  }

  assert( pParent->isInit );
  TRACE(("BALANCE: finished: old=%d new=%d cells=%d\n",
          nOld, nNew, nCell));

  /*
  ** Cleanup before returning.
  */
balance_cleanup:
  sqlite3ScratchFree(apCell);
  for(i=0; i<nOld; i++){
    releasePage(apOld[i]);
  }
  for(i=0; i<nNew; i++){
    releasePage(apNew[i]);
  }








































































































  return rc;
}


/*
** This function is called when the root page of a b-tree structure is
** overfull (has one or more overflow pages).

/*
** The page that pCur currently points to has just been modified in
** some way. This function figures out if this modification means the
** tree needs to be balanced, and if so calls the appropriate balancing 
** routine. Balancing routines are:
**
**   balance_quick()

**   balance_deeper()
**   balance_nonroot()





*/
static int balance(BtCursor *pCur){
  int rc = SQLITE_OK;
  const int nMin = pCur->pBt->usableSize * 2 / 3;
  u8 aBalanceQuickSpace[13];
  u8 *pFree = 0;

        rc = balance_deeper(pPage, &pCur->apPage[1]);
        if( rc==SQLITE_OK ){
          pCur->iPage = 1;
          pCur->aiIdx[0] = 0;
          pCur->aiIdx[1] = 0;
          assert( pCur->apPage[1]->nOverflow );
        }

      }else{













        break;
      }
    }else if( pPage->nOverflow==0 && pPage->nFree<=nMin ){
      break;
    }else{
      MemPage * const pParent = pCur->apPage[iPage-1];
      int const iIdx = pCur->aiIdx[iPage-1];

          ** different page). Once this subsequent call to balance_nonroot() 
          ** has completed, it is safe to release the pSpace buffer used by
          ** the previous call, as the overflow cell data will have been 
          ** copied either into the body of a database page or into the new
          ** pSpace buffer passed to the latter call to balance_nonroot().
          */
          u8 *pSpace = sqlite3PageMalloc(pCur->pBt->pageSize);
          rc = balance_nonroot(pParent, iIdx, pSpace, iPage==1);
          if( pFree ){
            /* If pFree is not NULL, it points to the pSpace buffer used 
            ** by a previous call to balance_nonroot(). Its contents are
            ** now stored either on real database pages or within the 
            ** new pSpace buffer, so it may be safely freed here. */
            sqlite3PageFree(pFree);
          }

          /* The pSpace buffer will be freed after the next call to
          ** balance_nonroot(), or just before this function returns, whichever
          ** comes first. */
          pFree = pSpace;

        }
      }

      pPage->nOverflow = 0;

      /* The next iteration of the do-loop balances the parent page. */
      releasePage(pPage);
      pCur->iPage--;
    }
  }while( rc==SQLITE_OK );

  if( pFree ){
    sqlite3PageFree(pFree);
  }
  return rc;
}







































































/*
** Insert a new record into the BTree.  The key is given by (pKey,nKey)
** and the data is given by (pData,nData).  The cursor is used only to
** define what table the record should be inserted into.  The cursor
** is left pointing at a random location.
**
** For an INTKEY table, only the nKey value of the key is used.  pKey is
** ignored.  For a ZERODATA table, the pData and nData are both ignored.
**
** If the seekResult parameter is non-zero, then a successful call to
** MovetoUnpacked() to seek cursor pCur to (pKey, nKey) has already
** been performed. seekResult is the search result returned (a negative
** number if pCur points at an entry that is smaller than (pKey, nKey), or
** a positive value if pCur points at an etry that is larger than 
** (pKey, nKey)). 
**
** If the seekResult parameter is 0, then cursor pCur may point to any 
** entry or to no entry at all. In this case this function has to seek
** the cursor before the new key can be inserted.
*/
int sqlite3BtreeInsert(
  BtCursor *pCur,                /* Insert data into the table of this cursor */
  const void *pKey, i64 nKey,    /* The key of the new record */
  const void *pData, int nData,  /* The data of the new record */
  int nZero,                     /* Number of extra 0 bytes to append to data */
  int appendBias,                /* True if this is likely an append */
  int seekResult                 /* Result of prior MovetoUnpacked() call */
){
  int rc;
  int loc = seekResult;
  int szNew;
  int idx;
  MemPage *pPage;
  Btree *p = pCur->pBtree;
  BtShared *pBt = p->pBt;
  unsigned char *oldCell;
  unsigned char *newCell = 0;

  assert( cursorHoldsMutex(pCur) );
  assert( pBt->inTransaction==TRANS_WRITE );
  assert( !pBt->readOnly );
  assert( pCur->wrFlag );
  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );

  /* If this is an insert into a table b-tree, invalidate any incrblob 
  ** cursors open on the row being replaced (assuming this is a replace
  ** operation - if it is not, the following is a no-op).  */
  if( pCur->pKeyInfo==0 ){
    invalidateIncrblobCursors(p, pCur->pgnoRoot, nKey, 0);
  }

  if( pCur->eState==CURSOR_FAULT ){
    return pCur->skip;
  }

  /* Save the positions of any other cursors open on this table.
  **
  ** In some cases, the call to btreeMoveto() below is a no-op. For
  ** example, when inserting data into a table with auto-generated integer
  ** keys, the VDBE layer invokes sqlite3BtreeLast() to figure out the 
  ** integer key to use. It then calls this function to actually insert the 
  ** data into the intkey B-Tree. In this case btreeMoveto() recognizes
  ** that the cursor is already where it needs to be and returns without
  ** doing any work. To avoid thwarting these optimizations, it is important
  ** not to clear the cursor here.
  */
  if(
    SQLITE_OK!=(rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur)) || (!loc &&
    SQLITE_OK!=(rc = btreeMoveto(pCur, pKey, nKey, appendBias, &loc))
  )){
    return rc;
  }
  assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) );

  pPage = pCur->apPage[pCur->iPage];
  assert( pPage->intKey || nKey>=0 );

  int iCellIdx;                        /* Index of cell to delete */
  int iCellDepth;                      /* Depth of node containing pCell */ 

  assert( cursorHoldsMutex(pCur) );
  assert( pBt->inTransaction==TRANS_WRITE );
  assert( !pBt->readOnly );
  assert( pCur->wrFlag );
  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
  assert( !hasReadConflicts(p, pCur->pgnoRoot) );

  if( NEVER(pCur->aiIdx[pCur->iPage]>=pCur->apPage[pCur->iPage]->nCell) 
   || NEVER(pCur->eState!=CURSOR_VALID)
  ){
    return SQLITE_ERROR;  /* Something has gone awry. */
  }

  /* If this is a delete operation to remove a row from a table b-tree,
  ** invalidate any incrblob cursors open on the row being deleted.  */
  if( pCur->pKeyInfo==0 ){
    invalidateIncrblobCursors(p, pCur->pgnoRoot, pCur->info.nKey, 0);



  }

  iCellDepth = pCur->iPage;
  iCellIdx = pCur->aiIdx[iCellDepth];
  pPage = pCur->apPage[iCellDepth];
  pCell = findCell(pPage, iCellIdx);

    */
    invalidateAllOverflowCache(pBt);

    /* Read the value of meta[3] from the database to determine where the
    ** root page of the new table should go. meta[3] is the largest root-page
    ** created so far, so the new root-page is (meta[3]+1).
    */
    sqlite3BtreeGetMeta(p, BTREE_LARGEST_ROOT_PAGE, &pgnoRoot);



    pgnoRoot++;

    /* The new root-page may not be allocated on a pointer-map page, or the
    ** PENDING_BYTE page.
    */
    while( pgnoRoot==PTRMAP_PAGENO(pBt, pgnoRoot) ||
        pgnoRoot==PENDING_BYTE_PAGE(pBt) ){

** entries in the table.
*/
int sqlite3BtreeClearTable(Btree *p, int iTable, int *pnChange){
  int rc;
  BtShared *pBt = p->pBt;
  sqlite3BtreeEnter(p);
  assert( p->inTrans==TRANS_WRITE );

  /* Invalidate all incrblob cursors open on table iTable (assuming iTable
  ** is the root of a table b-tree - if it is not, the following call is
  ** a no-op).  */
  invalidateIncrblobCursors(p, iTable, 0, 1);

  if( SQLITE_OK==(rc = saveAllCursors(pBt, (Pgno)iTable, 0)) ){


    rc = clearDatabasePage(pBt, (Pgno)iTable, 0, pnChange);
  }
  sqlite3BtreeLeave(p);
  return rc;
}

/*

  if( iTable>1 ){
#ifdef SQLITE_OMIT_AUTOVACUUM
    rc = freePage(pPage);
    releasePage(pPage);
#else
    if( pBt->autoVacuum ){
      Pgno maxRootPgno;
      sqlite3BtreeGetMeta(p, BTREE_LARGEST_ROOT_PAGE, &maxRootPgno);





      if( iTable==maxRootPgno ){
        /* If the table being dropped is the table with the largest root-page
        ** number in the database, put the root page on the free list. 
        */
        rc = freePage(pPage);
        releasePage(pPage);

  rc = btreeDropTable(p, iTable, piMoved);
  sqlite3BtreeLeave(p);
  return rc;
}


/*
** This function may only be called if the b-tree connection already
** has a read or write transaction open on the database.
**
** Read the meta-information out of a database file.  Meta[0]
** is the number of free pages currently in the database.  Meta[1]
** through meta[15] are available for use by higher layers.  Meta[0]
** is read-only, the others are read/write.
** 
** The schema layer numbers meta values differently.  At the schema
** layer (and the SetCookie and ReadCookie opcodes) the number of
** free pages is not visible.  So Cookie[0] is the same as Meta[1].
*/
void sqlite3BtreeGetMeta(Btree *p, int idx, u32 *pMeta){



  BtShared *pBt = p->pBt;

  sqlite3BtreeEnter(p);
  assert( p->inTrans>TRANS_NONE );






  assert( SQLITE_OK==querySharedCacheTableLock(p, MASTER_ROOT, READ_LOCK) );




  assert( pBt->pPage1 );
  assert( idx>=0 && idx<=15 );


















  *pMeta = get4byte(&pBt->pPage1->aData[36 + idx*4]);








  /* If auto-vacuum is disabled in this build and this is an auto-vacuum
  ** database, mark the database as read-only.  */

#ifdef SQLITE_OMIT_AUTOVACUUM
  if( idx==BTREE_LARGEST_ROOT_PAGE && *pMeta>0 ) pBt->readOnly = 1;
#endif









  sqlite3BtreeLeave(p);

}

/*
** Write meta-information back into the database.  Meta[0] is
** read-only and may not be written.
*/
int sqlite3BtreeUpdateMeta(Btree *p, int idx, u32 iMeta){

#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/*
** This routine does a complete check of the given BTree file.  aRoot[] is
** an array of pages numbers were each page number is the root page of
** a table.  nRoot is the number of entries in aRoot.
**
** A read-only or read-write transaction must be opened before calling
** this function.
**
** Write the number of error seen in *pnErr.  Except for some memory
** allocation errors,  an error message held in memory obtained from
** malloc is returned if *pnErr is non-zero.  If *pnErr==0 then NULL is
** returned.  If a memory allocation error occurs, NULL is returned.
*/
char *sqlite3BtreeIntegrityCheck(
  Btree *p,     /* The btree to be checked */
  int *aRoot,   /* An array of root pages numbers for individual trees */
  int nRoot,    /* Number of entries in aRoot[] */
  int mxErr,    /* Stop reporting errors after this many */
  int *pnErr    /* Write number of errors seen to this variable */
){
  Pgno i;
  int nRef;
  IntegrityCk sCheck;
  BtShared *pBt = p->pBt;
  char zErr[100];

  sqlite3BtreeEnter(p);
  assert( p->inTrans>TRANS_NONE && pBt->inTransaction>TRANS_NONE );
  nRef = sqlite3PagerRefcount(pBt->pPager);





  sCheck.pBt = pBt;
  sCheck.pPager = pBt->pPager;
  sCheck.nPage = pagerPagecount(sCheck.pBt);
  sCheck.mxErr = mxErr;
  sCheck.nErr = 0;
  sCheck.mallocFailed = 0;
  *pnErr = 0;
  if( sCheck.nPage==0 ){

    sqlite3BtreeLeave(p);
    return 0;
  }
  sCheck.anRef = sqlite3Malloc( (sCheck.nPage+1)*sizeof(sCheck.anRef[0]) );
  if( !sCheck.anRef ){

    *pnErr = 1;
    sqlite3BtreeLeave(p);
    return 0;
  }
  for(i=0; i<=sCheck.nPage; i++){ sCheck.anRef[i] = 0; }
  i = PENDING_BYTE_PAGE(pBt);
  if( i<=sCheck.nPage ){

#endif
  }

  /* Make sure this analysis did not leave any unref() pages.
  ** This is an internal consistency check; an integrity check
  ** of the integrity check.
  */

  if( NEVER(nRef != sqlite3PagerRefcount(pBt->pPager)) ){
    checkAppendMsg(&sCheck, 0, 
      "Outstanding page count goes from %d to %d during this analysis",
      nRef, sqlite3PagerRefcount(pBt->pPager)
    );
  }

/*
** Obtain a lock on the table whose root page is iTab.  The
** lock is a write lock if isWritelock is true or a read lock
** if it is false.
*/
int sqlite3BtreeLockTable(Btree *p, int iTab, u8 isWriteLock){
  int rc = SQLITE_OK;
  assert( p->inTrans!=TRANS_NONE );
  if( p->sharable ){
    u8 lockType = READ_LOCK + isWriteLock;
    assert( READ_LOCK+1==WRITE_LOCK );
    assert( isWriteLock==0 || isWriteLock==1 );

    sqlite3BtreeEnter(p);
    rc = querySharedCacheTableLock(p, iTab, lockType);
    if( rc==SQLITE_OK ){
      rc = setSharedCacheTableLock(p, iTab, lockType);
    }
    sqlite3BtreeLeave(p);
  }
  return rc;
}
#endif

#ifndef SQLITE_OMIT_INCRBLOB
/*
** Argument pCsr must be a cursor opened for writing on an 
** INTKEY table currently pointing at a valid table entry. 
** This function modifies the data stored as part of that entry.
** Only the data content may only be modified, it is not possible
** to change the length of the data stored.
*/
int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void *z){


  assert( cursorHoldsMutex(pCsr) );
  assert( sqlite3_mutex_held(pCsr->pBtree->db->mutex) );
  assert( pCsr->isIncrblobHandle );

  restoreCursorPosition(pCsr);
  assert( pCsr->eState!=CURSOR_REQUIRESEEK );
  if( pCsr->eState!=CURSOR_VALID ){
    return SQLITE_ABORT;
  }

  /* Check some preconditions: 
  **   (a) the cursor is open for writing,
  **   (b) there is no read-lock on the table being modified and
  **   (c) the cursor points at a valid row of an intKey table.
  */
  if( !pCsr->wrFlag ){
    return SQLITE_READONLY;
  }
  assert( !pCsr->pBt->readOnly && pCsr->pBt->inTransaction==TRANS_WRITE );
  assert( hasSharedCacheTableLock(pCsr->pBtree, pCsr->pgnoRoot, 0, 2) );
  assert( !hasReadConflicts(pCsr->pBtree, pCsr->pgnoRoot) );





  if( pCsr->eState==CURSOR_INVALID || !pCsr->apPage[pCsr->iPage]->intKey ){
    return SQLITE_ERROR;
  }

  return accessPayload(pCsr, offset, amt, (unsigned char *)z, 0, 1);
}

**    May you share freely, never taking more than you give.
**
*************************************************************************
** This header file defines the interface that the sqlite B-Tree file
** subsystem.  See comments in the source code for a detailed description
** of what each interface routine does.
**
** @(#) $Id: btree.h,v 1.118 2009/07/06 18:56:13 danielk1977 Exp $
*/
#ifndef _BTREE_H_
#define _BTREE_H_

/* TODO: This definition is just included so other modules compile. It
** needs to be revisited.
*/

int sqlite3BtreeRollback(Btree*);
int sqlite3BtreeBeginStmt(Btree*,int);
int sqlite3BtreeCreateTable(Btree*, int*, int flags);
int sqlite3BtreeIsInTrans(Btree*);
int sqlite3BtreeIsInReadTrans(Btree*);
int sqlite3BtreeIsInBackup(Btree*);
void *sqlite3BtreeSchema(Btree *, int, void(*)(void *));
int sqlite3BtreeSchemaLocked(Btree *pBtree);
int sqlite3BtreeLockTable(Btree *pBtree, int iTab, u8 isWriteLock);
int sqlite3BtreeSavepoint(Btree *, int, int);

const char *sqlite3BtreeGetFilename(Btree *);
const char *sqlite3BtreeGetJournalname(Btree *);
int sqlite3BtreeCopyFile(Btree *, Btree *);

int sqlite3BtreeIncrVacuum(Btree *);

/* The flags parameter to sqlite3BtreeCreateTable can be the bitwise OR
** of the following flags:
*/
#define BTREE_INTKEY     1    /* Table has only 64-bit signed integer keys */
#define BTREE_ZERODATA   2    /* Table has keys only - no data */
#define BTREE_LEAFDATA   4    /* Data stored in leaves only.  Implies INTKEY */

int sqlite3BtreeDropTable(Btree*, int, int*);
int sqlite3BtreeClearTable(Btree*, int, int*);
void sqlite3BtreeTripAllCursors(Btree*, int);

void sqlite3BtreeGetMeta(Btree *pBtree, int idx, u32 *pValue);
int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);

/*
** The second parameter to sqlite3BtreeGetMeta or sqlite3BtreeUpdateMeta
** should be one of the following values. The integer values are assigned 
** to constants so that the offset of the corresponding field in an
** SQLite database header may be found using the following formula:

  int wrFlag,                          /* 1 for writing.  0 for read-only */
  struct KeyInfo*,                     /* First argument to compare function */
  BtCursor *pCursor                    /* Space to write cursor structure */
);
int sqlite3BtreeCursorSize(void);

int sqlite3BtreeCloseCursor(BtCursor*);







int sqlite3BtreeMovetoUnpacked(
  BtCursor*,
  UnpackedRecord *pUnKey,
  i64 intKey,
  int bias,
  int *pRes
);

/*
** 2004 April 6
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** $Id: btreeInt.h,v 1.50 2009/07/02 07:47:33 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.

/*
** The in-memory image of a disk page has the auxiliary information appended
** to the end.  EXTRA_SIZE is the number of bytes of space needed to hold
** that extra information.
*/
#define EXTRA_SIZE sizeof(MemPage)

/*
** A linked list of the following structures is stored at BtShared.pLock.
** Locks are added (or upgraded from READ_LOCK to WRITE_LOCK) when a cursor 
** is opened on the table with root page BtShared.iTable. Locks are removed
** from this list when a transaction is committed or rolled back, or when
** a btree handle is closed.
*/
struct BtLock {
  Btree *pBtree;        /* Btree handle holding this lock */
  Pgno iTable;          /* Root page of table */
  u8 eLock;             /* READ_LOCK or WRITE_LOCK */
  BtLock *pNext;        /* Next in BtShared.pLock list */
};

/* Candidate values for BtLock.eLock */
#define READ_LOCK     1
#define WRITE_LOCK    2

/* A Btree handle
**
** A database connection contains a pointer to an instance of
** this object for every database file that it has open.  This structure
** is opaque to the database connection.  The database connection cannot
** see the internals of this structure and only deals with pointers to
** this structure.

  u8 inTrans;        /* TRANS_NONE, TRANS_READ or TRANS_WRITE */
  u8 sharable;       /* True if we can share pBt with another db */
  u8 locked;         /* True if db currently has pBt locked */
  int wantToLock;    /* Number of nested calls to sqlite3BtreeEnter() */
  int nBackup;       /* Number of backup operations reading this btree */
  Btree *pNext;      /* List of other sharable Btrees from the same db */
  Btree *pPrev;      /* Back pointer of the same list */
#ifndef SQLITE_OMIT_SHARED_CACHE
  BtLock lock;       /* Object used to lock page 1 */
#endif
};

/*
** Btree.inTrans may take one of the following values.
**
** If the shared-data extension is enabled, there may be multiple users
** of the Btree structure. At most one of these may open a write transaction,

  void *pKey;      /* Saved key that was cursor's last known position */
  i64 nKey;        /* Size of pKey, or last integer key */
  int skip;        /* (skip<0) -> Prev() is a no-op. (skip>0) -> Next() is */
#ifndef SQLITE_OMIT_INCRBLOB
  u8 isIncrblobHandle;      /* True if this cursor is an incr. io handle */
  Pgno *aOverflow;          /* Cache of overflow page locations */
#endif



  i16 iPage;                            /* Index of current page in apPage */
  MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
  u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
};

/*
** Potential values for BtCursor.eState.

#define CURSOR_FAULT             3

/* 
** The database page the PENDING_BYTE occupies. This page is never used.
*/
# define PENDING_BYTE_PAGE(pBt) PAGER_MJ_PGNO(pBt)



















/*
** These macros define the location of the pointer-map entry for a 
** database page. The first argument to each is the number of usable
** bytes on each page of the database (often 1024). The second is the
** page number to look up in the pointer map.
**
** PTRMAP_PAGENO returns the database page number of the pointer-map

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.556 2009/07/01 16:12:08 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Initialize the pParse structure as needed.
*/

#endif

      /* Once all the cookies have been verified and transactions opened, 
      ** obtain the required table-locks. This is a no-op unless the 
      ** shared-cache feature is enabled.
      */
      codeTableLocks(pParse);

      /* Initialize any AUTOINCREMENT data structures required.
      */
      sqlite3AutoincrementBegin(pParse);

      /* Finally, jump back to the beginning of the executable code. */
      sqlite3VdbeAddOp2(v, OP_Goto, 0, pParse->cookieGoto);
    }
  }


  /* Get the VDBE program ready for execution
  */

void sqlite3UnlinkAndDeleteIndex(sqlite3 *db, int iDb, const char *zIdxName){
  Index *pIndex;
  int len;
  Hash *pHash = &db->aDb[iDb].pSchema->idxHash;

  len = sqlite3Strlen30(zIdxName);
  pIndex = sqlite3HashInsert(pHash, zIdxName, len, 0);



  if( pIndex ){
    if( pIndex->pTable->pIndex==pIndex ){
      pIndex->pTable->pIndex = pIndex->pNext;
    }else{
      Index *p;
      /* Justification of ALWAYS();  The index must be on the list of
      ** indices. */
      p = pIndex->pTable->pIndex;

  Token *pAlias,          /* The right-hand side of the AS subexpression */
  Select *pSubquery,      /* A subquery used in place of a table name */
  Expr *pOn,              /* The ON clause of a join */
  IdList *pUsing          /* The USING clause of a join */
){
  struct SrcList_item *pItem;
  sqlite3 *db = pParse->db;
  if( !p && (pOn || pUsing) ){
    sqlite3ErrorMsg(pParse, "a JOIN clause is required before %s", 
      (pOn ? "ON" : "USING")
    );
    goto append_from_error;
  }
  p = sqlite3SrcListAppend(db, p, pTable, pDatabase);
  if( p==0 || NEVER(p->nSrc==0) ){




    goto append_from_error;
  }
  pItem = &p->a[p->nSrc-1];
  assert( pAlias!=0 );
  if( pAlias->n ){
    pItem->zAlias = sqlite3NameFromToken(db, pAlias);
  }
  pItem->pSelect = pSubquery;
  pItem->pOn = pOn;
  pItem->pUsing = pUsing;
  return p;

 append_from_error:
  assert( p==0 );
  sqlite3ExprDelete(db, pOn);
  sqlite3IdListDelete(db, pUsing);
  sqlite3SelectDelete(db, pSubquery);
  return 0;
}

/*
** Add an INDEXED BY or NOT INDEXED clause to the most recently added 
** element of the source-list passed as the second argument.
*/
void sqlite3SrcListIndexedBy(Parse *pParse, SrcList *p, Token *pIndexedBy){

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** in order to generate code for DELETE FROM statements.
**
** $Id: delete.c,v 1.204 2009/06/23 20:28:54 drh Exp $
*/
#include "sqliteInt.h"

/*
** Look up every table that is named in pSrc.  If any table is not found,
** add an error message to pParse->zErrMsg and return NULL.  If all tables
** are found, return a pointer to the last table.

    if( !isView  && !IsVirtual(pTab) ){
      for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
        sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
      }
      sqlite3VdbeAddOp1(v, OP_Close, iCur);
    }
  }

  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
  ** autoincrement tables.
  */
  if( pParse->nested==0 && pParse->trigStack==0 ){
    sqlite3AutoincrementEnd(pParse);
  }

  /*
  ** Return the number of rows that were deleted. If this routine is 
  ** generating code because of a call to sqlite3NestedParse(), do not
  ** invoke the callback function.
  */
  if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
**
** $Id: insert.c,v 1.269 2009/06/23 20:28:54 drh Exp $
*/
#include "sqliteInt.h"

/*
** Generate code that will open a table for reading.
*/
void sqlite3OpenTable(

#endif
  }
  return 0;
}

#ifndef SQLITE_OMIT_AUTOINCREMENT
/*
** Locate or create an AutoincInfo structure associated with table pTab


** which is in database iDb.  Return the register number for the register
** that holds the maximum rowid.

**
** There is at most one AutoincInfo structure per table even if the
** same table is autoincremented multiple times due to inserts within
** triggers.  A new AutoincInfo structure is created if this is the
** first use of table pTab.  On 2nd and subsequent uses, the original
** AutoincInfo structure is used.
**
** Three memory locations are allocated:
**
**   (1)  Register to hold the name of the pTab table.

**   (2)  Register to hold the maximum ROWID of pTab.
**   (3)  Register to hold the rowid in sqlite_sequence of pTab

**
** The 2nd register is the one that is returned.  That is all the
** insert routine needs to know about.
*/
static int autoIncBegin(
  Parse *pParse,      /* Parsing context */
  int iDb,            /* Index of the database holding pTab */
  Table *pTab         /* The table we are writing to */
){
  int memId = 0;      /* Register holding maximum rowid */
  if( pTab->tabFlags & TF_Autoincrement ){
    AutoincInfo *pInfo;

    pInfo = pParse->pAinc;
    while( pInfo && pInfo->pTab!=pTab ){ pInfo = pInfo->pNext; }
    if( pInfo==0 ){
      pInfo = sqlite3DbMallocRaw(pParse->db, sizeof(*pInfo));
      if( pInfo==0 ) return 0;
      pInfo->pNext = pParse->pAinc;
      pParse->pAinc = pInfo;
      pInfo->pTab = pTab;
      pInfo->iDb = iDb;
      pParse->nMem++;                  /* Register to hold name of table */
      pInfo->regCtr = ++pParse->nMem;  /* Max rowid register */
      pParse->nMem++;                  /* Rowid in sqlite_sequence */
    }
    memId = pInfo->regCtr;
  }
  return memId;
}

/*
** This routine generates code that will initialize all of the
** register used by the autoincrement tracker.  
*/
void sqlite3AutoincrementBegin(Parse *pParse){
  AutoincInfo *p;            /* Information about an AUTOINCREMENT */
  sqlite3 *db = pParse->db;  /* The database connection */
  Db *pDb;                   /* Database only autoinc table */
  int memId;                 /* Register holding max rowid */
  int addr;                  /* A VDBE address */
  Vdbe *v = pParse->pVdbe;   /* VDBE under construction */

  assert( v );   /* We failed long ago if this is not so */
  for(p = pParse->pAinc; p; p = p->pNext){
    pDb = &db->aDb[p->iDb];
    memId = p->regCtr;

    sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenRead);
    addr = sqlite3VdbeCurrentAddr(v);
    sqlite3VdbeAddOp4(v, OP_String8, 0, memId-1, 0, p->pTab->zName, 0);
    sqlite3VdbeAddOp2(v, OP_Rewind, 0, addr+9);
    sqlite3VdbeAddOp3(v, OP_Column, 0, 0, memId);
    sqlite3VdbeAddOp3(v, OP_Ne, memId-1, addr+7, memId);
    sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
    sqlite3VdbeAddOp2(v, OP_Rowid, 0, memId+1);
    sqlite3VdbeAddOp3(v, OP_Column, 0, 1, memId);
    sqlite3VdbeAddOp2(v, OP_Goto, 0, addr+9);
    sqlite3VdbeAddOp2(v, OP_Next, 0, addr+2);
    sqlite3VdbeAddOp2(v, OP_Integer, 0, memId);
    sqlite3VdbeAddOp0(v, OP_Close);
  }

}

/*
** Update the maximum rowid for an autoincrement calculation.
**
** This routine should be called when the top of the stack holds a
** new rowid that is about to be inserted.  If that new rowid is
** larger than the maximum rowid in the memId memory cell, then the
** memory cell is updated.  The stack is unchanged.
*/
static void autoIncStep(Parse *pParse, int memId, int regRowid){
  if( memId>0 ){
    sqlite3VdbeAddOp2(pParse->pVdbe, OP_MemMax, memId, regRowid);
  }
}

/*
** This routine generates the code needed to write autoincrement

** maximum rowid values back into the sqlite_sequence register.
** Every statement that might do an INSERT into an autoincrement
** table (either directly or through triggers) needs to call this
** routine just before the "exit" code.
*/

void sqlite3AutoincrementEnd(Parse *pParse){




  AutoincInfo *p;

  Vdbe *v = pParse->pVdbe;
  sqlite3 *db = pParse->db;



  assert( v );
  for(p = pParse->pAinc; p; p = p->pNext){
    Db *pDb = &db->aDb[p->iDb];
    int j1, j2, j3, j4, j5;
    int iRec;
    int memId = p->regCtr;

    iRec = sqlite3GetTempReg(pParse);
    sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenWrite);
    j1 = sqlite3VdbeAddOp1(v, OP_NotNull, memId+1);
    j2 = sqlite3VdbeAddOp0(v, OP_Rewind);
    j3 = sqlite3VdbeAddOp3(v, OP_Column, 0, 0, iRec);
    j4 = sqlite3VdbeAddOp3(v, OP_Eq, memId-1, 0, iRec);
    sqlite3VdbeAddOp2(v, OP_Next, 0, j3);
    sqlite3VdbeJumpHere(v, j2);
    sqlite3VdbeAddOp2(v, OP_NewRowid, 0, memId+1);
    j5 = sqlite3VdbeAddOp0(v, OP_Goto);
    sqlite3VdbeJumpHere(v, j4);
    sqlite3VdbeAddOp2(v, OP_Rowid, 0, memId+1);
    sqlite3VdbeJumpHere(v, j1);
    sqlite3VdbeJumpHere(v, j5);
    sqlite3VdbeAddOp3(v, OP_MakeRecord, memId-1, 2, iRec);
    sqlite3VdbeAddOp3(v, OP_Insert, 0, iRec, memId+1);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
    sqlite3VdbeAddOp0(v, OP_Close);
    sqlite3ReleaseTempReg(pParse, iRec);
  }
}
#else
/*
** If SQLITE_OMIT_AUTOINCREMENT is defined, then the three routines
** above are all no-ops
*/
# define autoIncBegin(A,B,C) (0)
# define autoIncStep(A,B,C)

#endif /* SQLITE_OMIT_AUTOINCREMENT */


/* Forward declaration */
static int xferOptimization(
  Parse *pParse,        /* Parser context */
  Table *pDest,         /* The table we are inserting into */

  ** very fast and which reduce fragmentation of indices.
  **
  ** This is the 2nd template.
  */
  if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){
    assert( !pTrigger );
    assert( pList==0 );
    goto insert_end;
  }
#endif /* SQLITE_OMIT_XFER_OPT */

  /* If this is an AUTOINCREMENT table, look up the sequence number in the
  ** sqlite_sequence table and store it in memory cell regAutoinc.
  */
  regAutoinc = autoIncBegin(pParse, iDb, pTab);

    /* Close all tables opened */
    sqlite3VdbeAddOp1(v, OP_Close, baseCur);
    for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){
      sqlite3VdbeAddOp1(v, OP_Close, idx+baseCur);
    }
  }

insert_end:
  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
  ** autoincrement tables.
  */
  if( pParse->nested==0 && pParse->trigStack==0 ){
    sqlite3AutoincrementEnd(pParse);
  }

  /*
  ** Return the number of rows inserted. If this routine is 
  ** generating code because of a call to sqlite3NestedParse(), do not
  ** invoke the callback function.
  */
  if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){

    assert( (pDest->tabFlags & TF_Autoincrement)==0 );
  }
  sqlite3VdbeAddOp2(v, OP_RowData, iSrc, regData);
  sqlite3VdbeAddOp3(v, OP_Insert, iDest, regData, regRowid);
  sqlite3VdbeChangeP5(v, OPFLAG_NCHANGE|OPFLAG_LASTROWID|OPFLAG_APPEND);
  sqlite3VdbeChangeP4(v, -1, pDest->zName, 0);
  sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1);

  for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){
    for(pSrcIdx=pSrc->pIndex; ALWAYS(pSrcIdx); pSrcIdx=pSrcIdx->pNext){
      if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break;
    }
    assert( pSrcIdx );
    sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0);
    sqlite3VdbeAddOp2(v, OP_Close, iDest, 0);

**
*************************************************************************
** 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 1.34 2009/07/03 19:18:43 drh Exp $
*/

#include "sqliteInt.h"

/*
** Execute SQL code.  Return one of the SQLITE_ success/failure
** codes.  Also write an error message into memory obtained from

  rc = sqlite3ApiExit(db, rc);
  if( rc!=SQLITE_OK && ALWAYS(rc==sqlite3_errcode(db)) && pzErrMsg ){
    int nErrMsg = 1 + sqlite3Strlen30(sqlite3_errmsg(db));
    *pzErrMsg = sqlite3Malloc(nErrMsg);
    if( *pzErrMsg ){
      memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg);
    }else{
      rc = SQLITE_NOMEM;
    }
  }else if( pzErrMsg ){
    *pzErrMsg = 0;
  }

  assert( (rc&db->errMask)==rc );
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

/* Driver template for the LEMON parser generator.
** The author disclaims copyright to this source code.
**
** This version of "lempar.c" is modified, slightly, for use by SQLite.
** The only modifications are the addition of a couple of NEVER()
** macros to disable tests that are needed in the case of a general
** LALR(1) grammar but which are always false in the
** specific grammar used by SQLite.
*/
/* First off, code is included that follows the "include" declaration
** in the input grammar file. */
#include <stdio.h>
%%
/* Next is all token values, in a form suitable for use by makeheaders.
** This section will be null unless lemon is run with the -m switch.
*/
/* 
** These constants (all generated automatically by the parser generator)
** specify the various kinds of tokens (terminals) that the parser
** understands. 
**
** Each symbol here is a terminal symbol in the grammar.
*/
%%
/* Make sure the INTERFACE macro is defined.
*/
#ifndef INTERFACE
# define INTERFACE 1
#endif
/* The next thing included is series of defines which control
** various aspects of the generated parser.
**    YYCODETYPE         is the data type used for storing terminal
**                       and nonterminal numbers.  "unsigned char" is
**                       used if there are fewer than 250 terminals
**                       and nonterminals.  "int" is used otherwise.
**    YYNOCODE           is a number of type YYCODETYPE which corresponds
**                       to no legal terminal or nonterminal number.  This
**                       number is used to fill in empty slots of the hash 
**                       table.
**    YYFALLBACK         If defined, this indicates that one or more tokens
**                       have fall-back values which should be used if the
**                       original value of the token will not parse.
**    YYACTIONTYPE       is the data type used for storing terminal
**                       and nonterminal numbers.  "unsigned char" is
**                       used if there are fewer than 250 rules and
**                       states combined.  "int" is used otherwise.
**    ParseTOKENTYPE     is the data type used for minor tokens given 
**                       directly to the parser from the tokenizer.
**    YYMINORTYPE        is the data type used for all minor tokens.
**                       This is typically a union of many types, one of
**                       which is ParseTOKENTYPE.  The entry in the union
**                       for base tokens is called "yy0".
**    YYSTACKDEPTH       is the maximum depth of the parser's stack.  If
**                       zero the stack is dynamically sized using realloc()
**    ParseARG_SDECL     A static variable declaration for the %extra_argument
**    ParseARG_PDECL     A parameter declaration for the %extra_argument
**    ParseARG_STORE     Code to store %extra_argument into yypParser
**    ParseARG_FETCH     Code to extract %extra_argument from yypParser
**    YYNSTATE           the combined number of states.
**    YYNRULE            the number of rules in the grammar
**    YYERRORSYMBOL      is the code number of the error symbol.  If not
**                       defined, then do no error processing.
*/
%%
#define YY_NO_ACTION      (YYNSTATE+YYNRULE+2)
#define YY_ACCEPT_ACTION  (YYNSTATE+YYNRULE+1)
#define YY_ERROR_ACTION   (YYNSTATE+YYNRULE)

/* The yyzerominor constant is used to initialize instances of
** YYMINORTYPE objects to zero. */
static const YYMINORTYPE yyzerominor = { 0 };

/* Define the yytestcase() macro to be a no-op if is not already defined
** otherwise.
**
** Applications can choose to define yytestcase() in the %include section
** to a macro that can assist in verifying code coverage.  For production
** code the yytestcase() macro should be turned off.  But it is useful
** for testing.
*/
#ifndef yytestcase
# define yytestcase(X)
#endif


/* Next are the tables used to determine what action to take based on the
** current state and lookahead token.  These tables are used to implement
** functions that take a state number and lookahead value and return an
** action integer.  
**
** Suppose the action integer is N.  Then the action is determined as
** follows
**
**   0 <= N < YYNSTATE                  Shift N.  That is, push the lookahead
**                                      token onto the stack and goto state N.
**
**   YYNSTATE <= N < YYNSTATE+YYNRULE   Reduce by rule N-YYNSTATE.
**
**   N == YYNSTATE+YYNRULE              A syntax error has occurred.
**
**   N == YYNSTATE+YYNRULE+1            The parser accepts its input.
**
**   N == YYNSTATE+YYNRULE+2            No such action.  Denotes unused
**                                      slots in the yy_action[] table.
**
** The action table is constructed as a single large table named yy_action[].
** Given state S and lookahead X, the action is computed as
**
**      yy_action[ yy_shift_ofst[S] + X ]
**
** If the index value yy_shift_ofst[S]+X is out of range or if the value
** yy_lookahead[yy_shift_ofst[S]+X] is not equal to X or if yy_shift_ofst[S]
** is equal to YY_SHIFT_USE_DFLT, it means that the action is not in the table
** and that yy_default[S] should be used instead.  
**
** The formula above is for computing the action when the lookahead is
** a terminal symbol.  If the lookahead is a non-terminal (as occurs after
** a reduce action) then the yy_reduce_ofst[] array is used in place of
** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of
** YY_SHIFT_USE_DFLT.
**
** The following are the tables generated in this section:
**
**  yy_action[]        A single table containing all actions.
**  yy_lookahead[]     A table containing the lookahead for each entry in
**                     yy_action.  Used to detect hash collisions.
**  yy_shift_ofst[]    For each state, the offset into yy_action for
**                     shifting terminals.
**  yy_reduce_ofst[]   For each state, the offset into yy_action for
**                     shifting non-terminals after a reduce.
**  yy_default[]       Default action for each state.
*/
%%
#define YY_SZ_ACTTAB (int)(sizeof(yy_action)/sizeof(yy_action[0]))

/* The next table maps tokens into fallback tokens.  If a construct
** like the following:
** 
**      %fallback ID X Y Z.
**
** appears in the grammar, then ID becomes a fallback token for X, Y,
** and Z.  Whenever one of the tokens X, Y, or Z is input to the parser
** but it does not parse, the type of the token is changed to ID and
** the parse is retried before an error is thrown.
*/
#ifdef YYFALLBACK
static const YYCODETYPE yyFallback[] = {
%%
};
#endif /* YYFALLBACK */

/* The following structure represents a single element of the
** parser's stack.  Information stored includes:
**
**   +  The state number for the parser at this level of the stack.
**
**   +  The value of the token stored at this level of the stack.
**      (In other words, the "major" token.)
**
**   +  The semantic value stored at this level of the stack.  This is
**      the information used by the action routines in the grammar.
**      It is sometimes called the "minor" token.
*/
struct yyStackEntry {
  YYACTIONTYPE stateno;  /* The state-number */
  YYCODETYPE major;      /* The major token value.  This is the code
                         ** number for the token at this stack level */
  YYMINORTYPE minor;     /* The user-supplied minor token value.  This
                         ** is the value of the token  */
};
typedef struct yyStackEntry yyStackEntry;

/* The state of the parser is completely contained in an instance of
** the following structure */
struct yyParser {
  int yyidx;                    /* Index of top element in stack */
#ifdef YYTRACKMAXSTACKDEPTH
  int yyidxMax;                 /* Maximum value of yyidx */
#endif
  int yyerrcnt;                 /* Shifts left before out of the error */
  ParseARG_SDECL                /* A place to hold %extra_argument */
#if YYSTACKDEPTH<=0
  int yystksz;                  /* Current side of the stack */
  yyStackEntry *yystack;        /* The parser's stack */
#else
  yyStackEntry yystack[YYSTACKDEPTH];  /* The parser's stack */
#endif
};
typedef struct yyParser yyParser;

#ifndef NDEBUG
#include <stdio.h>
static FILE *yyTraceFILE = 0;
static char *yyTracePrompt = 0;
#endif /* NDEBUG */

#ifndef NDEBUG
/* 
** Turn parser tracing on by giving a stream to which to write the trace
** and a prompt to preface each trace message.  Tracing is turned off
** by making either argument NULL 
**
** Inputs:
** <ul>
** <li> A FILE* to which trace output should be written.
**      If NULL, then tracing is turned off.
** <li> A prefix string written at the beginning of every
**      line of trace output.  If NULL, then tracing is
**      turned off.
** </ul>
**
** Outputs:
** None.
*/
void ParseTrace(FILE *TraceFILE, char *zTracePrompt){
  yyTraceFILE = TraceFILE;
  yyTracePrompt = zTracePrompt;
  if( yyTraceFILE==0 ) yyTracePrompt = 0;
  else if( yyTracePrompt==0 ) yyTraceFILE = 0;
}
#endif /* NDEBUG */

#ifndef NDEBUG
/* For tracing shifts, the names of all terminals and nonterminals
** are required.  The following table supplies these names */
static const char *const yyTokenName[] = { 
%%
};
#endif /* NDEBUG */

#ifndef NDEBUG
/* For tracing reduce actions, the names of all rules are required.
*/
static const char *const yyRuleName[] = {
%%
};
#endif /* NDEBUG */


#if YYSTACKDEPTH<=0
/*
** Try to increase the size of the parser stack.
*/
static void yyGrowStack(yyParser *p){
  int newSize;
  yyStackEntry *pNew;

  newSize = p->yystksz*2 + 100;
  pNew = realloc(p->yystack, newSize*sizeof(pNew[0]));
  if( pNew ){
    p->yystack = pNew;
    p->yystksz = newSize;
#ifndef NDEBUG
    if( yyTraceFILE ){
      fprintf(yyTraceFILE,"%sStack grows to %d entries!\n",
              yyTracePrompt, p->yystksz);
    }
#endif
  }
}
#endif

/* 
** This function allocates a new parser.
** The only argument is a pointer to a function which works like
** malloc.
**
** Inputs:
** A pointer to the function used to allocate memory.
**
** Outputs:
** A pointer to a parser.  This pointer is used in subsequent calls
** to Parse and ParseFree.
*/
void *ParseAlloc(void *(*mallocProc)(size_t)){
  yyParser *pParser;
  pParser = (yyParser*)(*mallocProc)( (size_t)sizeof(yyParser) );
  if( pParser ){
    pParser->yyidx = -1;
#ifdef YYTRACKMAXSTACKDEPTH
    pParser->yyidxMax = 0;
#endif
#if YYSTACKDEPTH<=0
    pParser->yystack = NULL;
    pParser->yystksz = 0;
    yyGrowStack(pParser);
#endif
  }
  return pParser;
}

/* The following function deletes the value associated with a
** symbol.  The symbol can be either a terminal or nonterminal.
** "yymajor" is the symbol code, and "yypminor" is a pointer to
** the value.
*/
static void yy_destructor(
  yyParser *yypParser,    /* The parser */
  YYCODETYPE yymajor,     /* Type code for object to destroy */
  YYMINORTYPE *yypminor   /* The object to be destroyed */
){
  ParseARG_FETCH;
  switch( yymajor ){
    /* Here is inserted the actions which take place when a
    ** terminal or non-terminal is destroyed.  This can happen
    ** when the symbol is popped from the stack during a
    ** reduce or during error processing or when a parser is 
    ** being destroyed before it is finished parsing.
    **
    ** Note: during a reduce, the only symbols destroyed are those
    ** which appear on the RHS of the rule, but which are not used
    ** inside the C code.
    */
%%
    default:  break;   /* If no destructor action specified: do nothing */
  }
}

/*
** Pop the parser's stack once.
**
** If there is a destructor routine associated with the token which
** is popped from the stack, then call it.
**
** Return the major token number for the symbol popped.
*/
static int yy_pop_parser_stack(yyParser *pParser){
  YYCODETYPE yymajor;
  yyStackEntry *yytos = &pParser->yystack[pParser->yyidx];

  /* There is no mechanism by which the parser stack can be popped below
  ** empty in SQLite.  */
  if( NEVER(pParser->yyidx<0) ) return 0;
#ifndef NDEBUG
  if( yyTraceFILE && pParser->yyidx>=0 ){
    fprintf(yyTraceFILE,"%sPopping %s\n",
      yyTracePrompt,
      yyTokenName[yytos->major]);
  }
#endif
  yymajor = yytos->major;
  yy_destructor(pParser, yymajor, &yytos->minor);
  pParser->yyidx--;
  return yymajor;
}

/* 
** Deallocate and destroy a parser.  Destructors are all called for
** all stack elements before shutting the parser down.
**
** Inputs:
** <ul>
** <li>  A pointer to the parser.  This should be a pointer
**       obtained from ParseAlloc.
** <li>  A pointer to a function used to reclaim memory obtained
**       from malloc.
** </ul>
*/
void ParseFree(
  void *p,                    /* The parser to be deleted */
  void (*freeProc)(void*)     /* Function used to reclaim memory */
){
  yyParser *pParser = (yyParser*)p;
  /* In SQLite, we never try to destroy a parser that was not successfully
  ** created in the first place. */
  if( NEVER(pParser==0) ) return;
  while( pParser->yyidx>=0 ) yy_pop_parser_stack(pParser);
#if YYSTACKDEPTH<=0
  free(pParser->yystack);
#endif
  (*freeProc)((void*)pParser);
}

/*
** Return the peak depth of the stack for a parser.
*/
#ifdef YYTRACKMAXSTACKDEPTH
int ParseStackPeak(void *p){
  yyParser *pParser = (yyParser*)p;
  return pParser->yyidxMax;
}
#endif

/*
** Find the appropriate action for a parser given the terminal
** look-ahead token iLookAhead.
**
** If the look-ahead token is YYNOCODE, then check to see if the action is
** independent of the look-ahead.  If it is, return the action, otherwise
** return YY_NO_ACTION.
*/
static int yy_find_shift_action(
  yyParser *pParser,        /* The parser */
  YYCODETYPE iLookAhead     /* The look-ahead token */
){
  int i;
  int stateno = pParser->yystack[pParser->yyidx].stateno;
 
  if( stateno>YY_SHIFT_MAX || (i = yy_shift_ofst[stateno])==YY_SHIFT_USE_DFLT ){
    return yy_default[stateno];
  }
  assert( iLookAhead!=YYNOCODE );
  i += iLookAhead;
  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
    /* The user of ";" instead of "\000" as a statement terminator in SQLite
    ** means that we always have a look-ahead token. */
    if( iLookAhead>0 ){
#ifdef YYFALLBACK
      YYCODETYPE iFallback;            /* Fallback token */
      if( iLookAhead<sizeof(yyFallback)/sizeof(yyFallback[0])
             && (iFallback = yyFallback[iLookAhead])!=0 ){
#ifndef NDEBUG
        if( yyTraceFILE ){
          fprintf(yyTraceFILE, "%sFALLBACK %s => %s\n",
             yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[iFallback]);
        }
#endif
        return yy_find_shift_action(pParser, iFallback);
      }
#endif
#ifdef YYWILDCARD
      {
        int j = i - iLookAhead + YYWILDCARD;
        if( j>=0 && j<YY_SZ_ACTTAB && yy_lookahead[j]==YYWILDCARD ){
#ifndef NDEBUG
          if( yyTraceFILE ){
            fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
               yyTracePrompt, yyTokenName[iLookAhead], yyTokenName[YYWILDCARD]);
          }
#endif /* NDEBUG */
          return yy_action[j];
        }
      }
#endif /* YYWILDCARD */
    }
    return yy_default[stateno];
  }else{
    return yy_action[i];
  }
}

/*
** Find the appropriate action for a parser given the non-terminal
** look-ahead token iLookAhead.
**
** If the look-ahead token is YYNOCODE, then check to see if the action is
** independent of the look-ahead.  If it is, return the action, otherwise
** return YY_NO_ACTION.
*/
static int yy_find_reduce_action(
  int stateno,              /* Current state number */
  YYCODETYPE iLookAhead     /* The look-ahead token */
){
  int i;
#ifdef YYERRORSYMBOL
  if( stateno>YY_REDUCE_MAX ){
    return yy_default[stateno];
  }
#else
  assert( stateno<=YY_REDUCE_MAX );
#endif
  i = yy_reduce_ofst[stateno];
  assert( i!=YY_REDUCE_USE_DFLT );
  assert( iLookAhead!=YYNOCODE );
  i += iLookAhead;
#ifdef YYERRORSYMBOL
  if( i<0 || i>=YY_SZ_ACTTAB || yy_lookahead[i]!=iLookAhead ){
    return yy_default[stateno];
  }
#else
  assert( i>=0 && i<YY_SZ_ACTTAB );
  assert( yy_lookahead[i]==iLookAhead );
#endif
  return yy_action[i];
}

/*
** The following routine is called if the stack overflows.
*/
static void yyStackOverflow(yyParser *yypParser, YYMINORTYPE *yypMinor){
   ParseARG_FETCH;
   yypParser->yyidx--;
#ifndef NDEBUG
   if( yyTraceFILE ){
     fprintf(yyTraceFILE,"%sStack Overflow!\n",yyTracePrompt);
   }
#endif
   while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
   /* Here code is inserted which will execute if the parser
   ** stack every overflows */
%%
   ParseARG_STORE; /* Suppress warning about unused %extra_argument var */
}

/*
** Perform a shift action.
*/
static void yy_shift(
  yyParser *yypParser,          /* The parser to be shifted */
  int yyNewState,               /* The new state to shift in */
  int yyMajor,                  /* The major token to shift in */
  YYMINORTYPE *yypMinor         /* Pointer to the minor token to shift in */
){
  yyStackEntry *yytos;
  yypParser->yyidx++;
#ifdef YYTRACKMAXSTACKDEPTH
  if( yypParser->yyidx>yypParser->yyidxMax ){
    yypParser->yyidxMax = yypParser->yyidx;
  }
#endif
#if YYSTACKDEPTH>0 
  if( yypParser->yyidx>=YYSTACKDEPTH ){
    yyStackOverflow(yypParser, yypMinor);
    return;
  }
#else
  if( yypParser->yyidx>=yypParser->yystksz ){
    yyGrowStack(yypParser);
    if( yypParser->yyidx>=yypParser->yystksz ){
      yyStackOverflow(yypParser, yypMinor);
      return;
    }
  }
#endif
  yytos = &yypParser->yystack[yypParser->yyidx];
  yytos->stateno = (YYACTIONTYPE)yyNewState;
  yytos->major = (YYCODETYPE)yyMajor;
  yytos->minor = *yypMinor;
#ifndef NDEBUG
  if( yyTraceFILE && yypParser->yyidx>0 ){
    int i;
    fprintf(yyTraceFILE,"%sShift %d\n",yyTracePrompt,yyNewState);
    fprintf(yyTraceFILE,"%sStack:",yyTracePrompt);
    for(i=1; i<=yypParser->yyidx; i++)
      fprintf(yyTraceFILE," %s",yyTokenName[yypParser->yystack[i].major]);
    fprintf(yyTraceFILE,"\n");
  }
#endif
}

/* The following table contains information about every rule that
** is used during the reduce.
*/
static const struct {
  YYCODETYPE lhs;         /* Symbol on the left-hand side of the rule */
  unsigned char nrhs;     /* Number of right-hand side symbols in the rule */
} yyRuleInfo[] = {
%%
};

static void yy_accept(yyParser*);  /* Forward Declaration */

/*
** Perform a reduce action and the shift that must immediately
** follow the reduce.
*/
static void yy_reduce(
  yyParser *yypParser,         /* The parser */
  int yyruleno                 /* Number of the rule by which to reduce */
){
  int yygoto;                     /* The next state */
  int yyact;                      /* The next action */
  YYMINORTYPE yygotominor;        /* The LHS of the rule reduced */
  yyStackEntry *yymsp;            /* The top of the parser's stack */
  int yysize;                     /* Amount to pop the stack */
  ParseARG_FETCH;
  yymsp = &yypParser->yystack[yypParser->yyidx];
#ifndef NDEBUG
  if( yyTraceFILE && yyruleno>=0 
        && yyruleno<(int)(sizeof(yyRuleName)/sizeof(yyRuleName[0])) ){
    fprintf(yyTraceFILE, "%sReduce [%s].\n", yyTracePrompt,
      yyRuleName[yyruleno]);
  }
#endif /* NDEBUG */

  /* Silence complaints from purify about yygotominor being uninitialized
  ** in some cases when it is copied into the stack after the following
  ** switch.  yygotominor is uninitialized when a rule reduces that does
  ** not set the value of its left-hand side nonterminal.  Leaving the
  ** value of the nonterminal uninitialized is utterly harmless as long
  ** as the value is never used.  So really the only thing this code
  ** accomplishes is to quieten purify.  
  **
  ** 2007-01-16:  The wireshark project (www.wireshark.org) reports that
  ** without this code, their parser segfaults.  I'm not sure what there
  ** parser is doing to make this happen.  This is the second bug report
  ** from wireshark this week.  Clearly they are stressing Lemon in ways
  ** that it has not been previously stressed...  (SQLite ticket #2172)
  */
  /*memset(&yygotominor, 0, sizeof(yygotominor));*/
  yygotominor = yyzerominor;


  switch( yyruleno ){
  /* Beginning here are the reduction cases.  A typical example
  ** follows:
  **   case 0:
  **  #line <lineno> <grammarfile>
  **     { ... }           // User supplied code
  **  #line <lineno> <thisfile>
  **     break;
  */
%%
  };
  yygoto = yyRuleInfo[yyruleno].lhs;
  yysize = yyRuleInfo[yyruleno].nrhs;
  yypParser->yyidx -= yysize;
  yyact = yy_find_reduce_action(yymsp[-yysize].stateno,(YYCODETYPE)yygoto);
  if( yyact < YYNSTATE ){
#ifdef NDEBUG
    /* If we are not debugging and the reduce action popped at least
    ** one element off the stack, then we can push the new element back
    ** onto the stack here, and skip the stack overflow test in yy_shift().
    ** That gives a significant speed improvement. */
    if( yysize ){
      yypParser->yyidx++;
      yymsp -= yysize-1;
      yymsp->stateno = (YYACTIONTYPE)yyact;
      yymsp->major = (YYCODETYPE)yygoto;
      yymsp->minor = yygotominor;
    }else
#endif
    {
      yy_shift(yypParser,yyact,yygoto,&yygotominor);
    }
  }else{
    assert( yyact == YYNSTATE + YYNRULE + 1 );
    yy_accept(yypParser);
  }
}

/*
** The following code executes when the parse fails
*/
#ifndef YYNOERRORRECOVERY
static void yy_parse_failed(
  yyParser *yypParser           /* The parser */
){
  ParseARG_FETCH;
#ifndef NDEBUG
  if( yyTraceFILE ){
    fprintf(yyTraceFILE,"%sFail!\n",yyTracePrompt);
  }
#endif
  while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
  /* Here code is inserted which will be executed whenever the
  ** parser fails */
%%
  ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */
}
#endif /* YYNOERRORRECOVERY */

/*
** The following code executes when a syntax error first occurs.
*/
static void yy_syntax_error(
  yyParser *yypParser,           /* The parser */
  int yymajor,                   /* The major type of the error token */
  YYMINORTYPE yyminor            /* The minor type of the error token */
){
  ParseARG_FETCH;
#define TOKEN (yyminor.yy0)
%%
  ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */
}

/*
** The following is executed when the parser accepts
*/
static void yy_accept(
  yyParser *yypParser           /* The parser */
){
  ParseARG_FETCH;
#ifndef NDEBUG
  if( yyTraceFILE ){
    fprintf(yyTraceFILE,"%sAccept!\n",yyTracePrompt);
  }
#endif
  while( yypParser->yyidx>=0 ) yy_pop_parser_stack(yypParser);
  /* Here code is inserted which will be executed whenever the
  ** parser accepts */
%%
  ParseARG_STORE; /* Suppress warning about unused %extra_argument variable */
}

/* The main parser program.
** The first argument is a pointer to a structure obtained from
** "ParseAlloc" which describes the current state of the parser.
** The second argument is the major token number.  The third is
** the minor token.  The fourth optional argument is whatever the
** user wants (and specified in the grammar) and is available for
** use by the action routines.
**
** Inputs:
** <ul>
** <li> A pointer to the parser (an opaque structure.)
** <li> The major token number.
** <li> The minor token number.
** <li> An option argument of a grammar-specified type.
** </ul>
**
** Outputs:
** None.
*/
void Parse(
  void *yyp,                   /* The parser */
  int yymajor,                 /* The major token code number */
  ParseTOKENTYPE yyminor       /* The value for the token */
  ParseARG_PDECL               /* Optional %extra_argument parameter */
){
  YYMINORTYPE yyminorunion;
  int yyact;            /* The parser action. */
  int yyendofinput;     /* True if we are at the end of input */
#ifdef YYERRORSYMBOL
  int yyerrorhit = 0;   /* True if yymajor has invoked an error */
#endif
  yyParser *yypParser;  /* The parser */

  /* (re)initialize the parser, if necessary */
  yypParser = (yyParser*)yyp;
  if( yypParser->yyidx<0 ){
#if YYSTACKDEPTH<=0
    if( yypParser->yystksz <=0 ){
      /*memset(&yyminorunion, 0, sizeof(yyminorunion));*/
      yyminorunion = yyzerominor;
      yyStackOverflow(yypParser, &yyminorunion);
      return;
    }
#endif
    yypParser->yyidx = 0;
    yypParser->yyerrcnt = -1;
    yypParser->yystack[0].stateno = 0;
    yypParser->yystack[0].major = 0;
  }
  yyminorunion.yy0 = yyminor;
  yyendofinput = (yymajor==0);
  ParseARG_STORE;

#ifndef NDEBUG
  if( yyTraceFILE ){
    fprintf(yyTraceFILE,"%sInput %s\n",yyTracePrompt,yyTokenName[yymajor]);
  }
#endif

  do{
    yyact = yy_find_shift_action(yypParser,(YYCODETYPE)yymajor);
    if( yyact<YYNSTATE ){
      assert( !yyendofinput );  /* Impossible to shift the $ token */
      yy_shift(yypParser,yyact,yymajor,&yyminorunion);
      yypParser->yyerrcnt--;
      yymajor = YYNOCODE;
    }else if( yyact < YYNSTATE + YYNRULE ){
      yy_reduce(yypParser,yyact-YYNSTATE);
    }else{
      assert( yyact == YY_ERROR_ACTION );
#ifdef YYERRORSYMBOL
      int yymx;
#endif
#ifndef NDEBUG
      if( yyTraceFILE ){
        fprintf(yyTraceFILE,"%sSyntax Error!\n",yyTracePrompt);
      }
#endif
#ifdef YYERRORSYMBOL
      /* A syntax error has occurred.
      ** The response to an error depends upon whether or not the
      ** grammar defines an error token "ERROR".  
      **
      ** This is what we do if the grammar does define ERROR:
      **
      **  * Call the %syntax_error function.
      **
      **  * Begin popping the stack until we enter a state where
      **    it is legal to shift the error symbol, then shift
      **    the error symbol.
      **
      **  * Set the error count to three.
      **
      **  * Begin accepting and shifting new tokens.  No new error
      **    processing will occur until three tokens have been
      **    shifted successfully.
      **
      */
      if( yypParser->yyerrcnt<0 ){
        yy_syntax_error(yypParser,yymajor,yyminorunion);
      }
      yymx = yypParser->yystack[yypParser->yyidx].major;
      if( yymx==YYERRORSYMBOL || yyerrorhit ){
#ifndef NDEBUG
        if( yyTraceFILE ){
          fprintf(yyTraceFILE,"%sDiscard input token %s\n",
             yyTracePrompt,yyTokenName[yymajor]);
        }
#endif
        yy_destructor(yypParser, (YYCODETYPE)yymajor,&yyminorunion);
        yymajor = YYNOCODE;
      }else{
         while(
          yypParser->yyidx >= 0 &&
          yymx != YYERRORSYMBOL &&
          (yyact = yy_find_reduce_action(
                        yypParser->yystack[yypParser->yyidx].stateno,
                        YYERRORSYMBOL)) >= YYNSTATE
        ){
          yy_pop_parser_stack(yypParser);
        }
        if( yypParser->yyidx < 0 || yymajor==0 ){
          yy_destructor(yypParser,(YYCODETYPE)yymajor,&yyminorunion);
          yy_parse_failed(yypParser);
          yymajor = YYNOCODE;
        }else if( yymx!=YYERRORSYMBOL ){
          YYMINORTYPE u2;
          u2.YYERRSYMDT = 0;
          yy_shift(yypParser,yyact,YYERRORSYMBOL,&u2);
        }
      }
      yypParser->yyerrcnt = 3;
      yyerrorhit = 1;
#elif defined(YYNOERRORRECOVERY)
      /* If the YYNOERRORRECOVERY macro is defined, then do not attempt to
      ** do any kind of error recovery.  Instead, simply invoke the syntax
      ** error routine and continue going as if nothing had happened.
      **
      ** Applications can set this macro (for example inside %include) if
      ** they intend to abandon the parse upon the first syntax error seen.
      */
      yy_syntax_error(yypParser,yymajor,yyminorunion);
      yy_destructor(yypParser,(YYCODETYPE)yymajor,&yyminorunion);
      yymajor = YYNOCODE;
      
#else  /* YYERRORSYMBOL is not defined */
      /* This is what we do if the grammar does not define ERROR:
      **
      **  * Report an error message, and throw away the input token.
      **
      **  * If the input token is $, then fail the parse.
      **
      ** As before, subsequent error messages are suppressed until
      ** three input tokens have been successfully shifted.
      */
      if( yypParser->yyerrcnt<=0 ){
        yy_syntax_error(yypParser,yymajor,yyminorunion);
      }
      yypParser->yyerrcnt = 3;
      yy_destructor(yypParser,(YYCODETYPE)yymajor,&yyminorunion);
      if( yyendofinput ){
        yy_parse_failed(yypParser);
      }
      yymajor = YYNOCODE;
#endif
    }
  }while( yymajor!=YYNOCODE && yypParser->yyidx>=0 );
  return;
}

**
*************************************************************************
** 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: main.c,v 1.560 2009/06/26 15:14:55 drh Exp $
*/
#include "sqliteInt.h"

#ifdef SQLITE_ENABLE_FTS3
# include "fts3.h"
#endif
#ifdef SQLITE_ENABLE_RTREE

    /* SQLITE_CORRUPT     */ "database disk image is malformed",
    /* SQLITE_NOTFOUND    */ 0,
    /* SQLITE_FULL        */ "database or disk is full",
    /* SQLITE_CANTOPEN    */ "unable to open database file",
    /* SQLITE_PROTOCOL    */ 0,
    /* SQLITE_EMPTY       */ "table contains no data",
    /* SQLITE_SCHEMA      */ "database schema has changed",
    /* SQLITE_TOOBIG      */ "string or blob too big",
    /* SQLITE_CONSTRAINT  */ "constraint failed",
    /* SQLITE_MISMATCH    */ "datatype mismatch",
    /* SQLITE_MISUSE      */ "library routine called out of sequence",
    /* SQLITE_NOLFS       */ "large file support is disabled",
    /* SQLITE_AUTH        */ "authorization denied",
    /* SQLITE_FORMAT      */ "auxiliary database format error",
    /* SQLITE_RANGE       */ "bind or column index out of range",

      sqlite3_free(db);
      db = 0;
      goto opendb_out;
    }
  }
  sqlite3_mutex_enter(db->mutex);
  db->errMask = 0xff;

  db->nDb = 2;
  db->magic = SQLITE_MAGIC_BUSY;
  db->aDb = db->aDbStatic;

  assert( sizeof(db->aLimit)==sizeof(aHardLimit) );
  memcpy(db->aLimit, aHardLimit, sizeof(db->aLimit));
  db->autoCommit = 1;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** Memory allocation functions used throughout sqlite.
**
** $Id: malloc.c,v 1.64 2009/06/27 00:48:33 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>

/*
** This routine runs when the memory allocator sees that the
** total memory allocation is about to exceed the soft heap

/*
** Allocate memory.  This routine is like sqlite3_malloc() except that it
** assumes the memory subsystem has already been initialized.
*/
void *sqlite3Malloc(int n){
  void *p;
  if( n<=0 || n>=0x7fffff00 ){


    /* A memory allocation of a number of bytes which is near the maximum
    ** signed integer value might cause an integer overflow inside of the
    ** xMalloc().  Hence we limit the maximum size to 0x7fffff00, giving
    ** 255 bytes of overhead.  SQLite itself will never use anything near


    ** this amount.  The only way to reach the limit is with sqlite3_malloc() */
    p = 0;
  }else if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    mallocWithAlarm(n, &p);
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    p = sqlite3GlobalConfig.m.xMalloc(n);

*/
void *sqlite3Realloc(void *pOld, int nBytes){
  int nOld, nNew;
  void *pNew;
  if( pOld==0 ){
    return sqlite3Malloc(nBytes);
  }
  if( nBytes<=0 ){

    sqlite3_free(pOld);
    return 0;
  }
  if( nBytes>=0x7fffff00 ){
    /* The 0x7ffff00 limit term is explained in comments on sqlite3Malloc() */
    return 0;
  }
  nOld = sqlite3MallocSize(pOld);
  if( sqlite3GlobalConfig.bMemstat ){
    sqlite3_mutex_enter(mem0.mutex);
    sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, nBytes);
    nNew = sqlite3GlobalConfig.m.xRoundup(nBytes);
    if( nOld==nNew ){

**   *  Definitions of sqlite3_io_methods objects for all locking
**      methods plus "finder" functions for each locking method.
**   *  sqlite3_vfs method implementations.
**   *  Locking primitives for the proxy uber-locking-method. (MacOSX only)
**   *  Definitions of sqlite3_vfs objects for all locking methods
**      plus implementations of sqlite3_os_init() and sqlite3_os_end().
**
** $Id: os_unix.c,v 1.254 2009/07/03 12:57:58 drh Exp $
*/
#include "sqliteInt.h"
#if SQLITE_OS_UNIX              /* This file is used on unix only */

/*
** There are various methods for file locking used for concurrency
** control:

  l.l_whence = SEEK_SET;
  rc = fcntl(fd_orig, F_SETLK, &l);
  if( rc!=0 ) return;
  memset(&d, 0, sizeof(d));
  d.fd = fd;
  d.lock = l;
  d.lock.l_type = F_WRLCK;
  if( pthread_create(&t, 0, threadLockingTest, &d)==0 ){
    pthread_join(t, 0);
  }
  close(fd);
  if( d.result!=0 ) return;
  threadsOverrideEachOthersLocks = (d.lock.l_type==F_UNLCK);
}
#endif /* SQLITE_THREADSAFE && defined(__linux__) */

/*
** Release a unixLockInfo structure previously allocated by findLockInfo().
*/
static void releaseLockInfo(struct unixLockInfo *pLock){
  if( pLock ){
    pLock->nRef--;

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.603 2009/06/26 12:15:23 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"

/*
** Macros for troubleshooting.  Normally turned off
*/

  for(ii=0; ii<pPager->nSavepoint; ii++){
    if( pPager->aSavepoint[ii].iHdrOffset==0 ){
      pPager->aSavepoint[ii].iHdrOffset = pPager->journalOff;
    }
  }

  pPager->journalHdr = pPager->journalOff = journalHdrOffset(pPager);


  /* 
  ** Write the nRec Field - the number of page records that follow this
  ** journal header. Normally, zero is written to this value at this time.
  ** After the records are added to the journal (and the journal synced, 
  ** if in full-sync mode), the zero is overwritten with the true number
  ** of records (see syncJournal()).

  **   * When the SQLITE_IOCAP_SAFE_APPEND flag is set. This guarantees
  **     that garbage data is never appended to the journal file.
  */
  assert( isOpen(pPager->fd) || pPager->noSync );
  if( (pPager->noSync) || (pPager->journalMode==PAGER_JOURNALMODE_MEMORY)
   || (sqlite3OsDeviceCharacteristics(pPager->fd)&SQLITE_IOCAP_SAFE_APPEND) 
  ){
    memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
    put32bits(&zHeader[sizeof(aJournalMagic)], 0xffffffff);
  }else{
    zHeader[0] = '\0';
    put32bits(&zHeader[sizeof(aJournalMagic)], 0);
  }

  /* The random check-hash initialiser */ 
  sqlite3_randomness(sizeof(pPager->cksumInit), &pPager->cksumInit);
  put32bits(&zHeader[sizeof(aJournalMagic)+4], pPager->cksumInit);
  /* The initial database size */

**
** If the journal header file appears to be corrupted, SQLITE_DONE is
** returned and *pNRec and *PDbSize are undefined.  If JOURNAL_HDR_SZ bytes
** cannot be read from the journal file an error code is returned.
*/
static int readJournalHdr(
  Pager *pPager,               /* Pager object */
  int isHot,
  i64 journalSize,             /* Size of the open journal file in bytes */
  u32 *pNRec,                  /* OUT: Value read from the nRec field */
  u32 *pDbSize                 /* OUT: Value of original database size field */
){
  int rc;                      /* Return code */
  unsigned char aMagic[8];     /* A buffer to hold the magic header */
  i64 iHdrOff;                 /* Offset of journal header being read */

  iHdrOff = pPager->journalOff;

  /* Read in the first 8 bytes of the journal header. If they do not match
  ** the  magic string found at the start of each journal header, return
  ** SQLITE_DONE. If an IO error occurs, return an error code. Otherwise,
  ** proceed.
  */
  if( isHot || iHdrOff!=pPager->journalHdr ){
    rc = sqlite3OsRead(pPager->jfd, aMagic, sizeof(aMagic), iHdrOff);
    if( rc ){
      return rc;
    }
    if( memcmp(aMagic, aJournalMagic, sizeof(aMagic))!=0 ){
      return SQLITE_DONE;
    }
  }

  /* Read the first three 32-bit fields of the journal header: The nRec
  ** field, the checksum-initializer and the database size at the start
  ** of the transaction. Return an error code if anything goes wrong.
  */
  if( SQLITE_OK!=(rc = read32bits(pPager->jfd, iHdrOff+8, pNRec))

    int isUnsync = 0;

    /* Read the next journal header from the journal file.  If there are
    ** not enough bytes left in the journal file for a complete header, or
    ** it is corrupted, then a process must of failed while writing it.
    ** This indicates nothing more needs to be rolled back.
    */
    rc = readJournalHdr(pPager, isHot, szJ, &nRec, &mxPg);
    if( rc!=SQLITE_OK ){ 
      if( rc==SQLITE_DONE ){
        rc = SQLITE_OK;
      }
      goto end_playback;
    }

  ** of the main journal file.  Continue to skip out-of-range pages and
  ** continue adding pages rolled back to pDone.
  */
  while( rc==SQLITE_OK && pPager->journalOff<szJ ){
    u32 ii;            /* Loop counter */
    u32 nJRec = 0;     /* Number of Journal Records */
    u32 dummy;
    rc = readJournalHdr(pPager, 0, szJ, &nJRec, &dummy);
    assert( rc!=SQLITE_DONE );

    /*
    ** The "pPager->journalHdr+JOURNAL_HDR_SZ(pPager)==pPager->journalOff"
    ** test is related to ticket #2565.  See the discussion in the
    ** pager_playback() function for additional information.
    */

    assert( !pPager->tempFile );
    if( pPager->journalMode!=PAGER_JOURNALMODE_MEMORY ){
      int rc;                              /* Return code */
      const int iDc = sqlite3OsDeviceCharacteristics(pPager->fd);
      assert( isOpen(pPager->jfd) );

      if( 0==(iDc&SQLITE_IOCAP_SAFE_APPEND) ){






        /* This block deals with an obscure problem. If the last connection
        ** that wrote to this database was operating in persistent-journal
        ** mode, then the journal file may at this point actually be larger
        ** than Pager.journalOff bytes. If the next thing in the journal
        ** file happens to be a journal-header (written as part of the
        ** previous connections transaction), and a crash or power-failure 
        ** occurs after nRec is updated but before this connection writes 

        ** byte to the start of it to prevent it from being recognized.
        **
        ** Variable iNextHdrOffset is set to the offset at which this
        ** problematic header will occur, if it exists. aMagic is used 
        ** as a temporary buffer to inspect the first couple of bytes of
        ** the potential journal header.
        */
        i64 iNextHdrOffset;
        u8 aMagic[8];
	u8 zHeader[sizeof(aJournalMagic)+4];

	memcpy(zHeader, aJournalMagic, sizeof(aJournalMagic));
	put32bits(&zHeader[sizeof(aJournalMagic)], pPager->nRec);

        iNextHdrOffset = journalHdrOffset(pPager);
        rc = sqlite3OsRead(pPager->jfd, aMagic, 8, iNextHdrOffset);
        if( rc==SQLITE_OK && 0==memcmp(aMagic, aJournalMagic, 8) ){
          static const u8 zerobyte = 0;
          rc = sqlite3OsWrite(pPager->jfd, &zerobyte, 1, iNextHdrOffset);
        }
        if( rc!=SQLITE_OK && rc!=SQLITE_IOERR_SHORT_READ ){
          return rc;

        */
        if( pPager->fullSync && 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
          PAGERTRACE(("SYNC journal of %d\n", PAGERID(pPager)));
          IOTRACE(("JSYNC %p\n", pPager))
          rc = sqlite3OsSync(pPager->jfd, pPager->sync_flags);
          if( rc!=SQLITE_OK ) return rc;
        }
        IOTRACE(("JHDR %p %lld\n", pPager, pPager->journalHdr));
        rc = sqlite3OsWrite(
            pPager->jfd, zHeader, sizeof(zHeader), pPager->journalHdr
	);
        if( rc!=SQLITE_OK ) return rc;
      }
      if( 0==(iDc&SQLITE_IOCAP_SEQUENTIAL) ){
        PAGERTRACE(("SYNC journal of %d\n", PAGERID(pPager)));
        IOTRACE(("JSYNC %p\n", pPager))
        rc = sqlite3OsSync(pPager->jfd, pPager->sync_flags| 
          (pPager->sync_flags==SQLITE_SYNC_FULL?SQLITE_SYNC_DATAONLY:0)

**
*************************************************************************
** This file contains SQLite's grammar for SQL.  Process this file
** using the lemon parser generator to generate C code that runs
** the parser.  Lemon will also generate a header file containing
** numeric codes for all of the tokens.
**
** @(#) $Id: parse.y,v 1.285 2009/07/03 15:37:28 drh Exp $
*/

// All token codes are small integers with #defines that begin with "TK_"
%token_prefix TK_

// The type of the data attached to each token is Token.  This is also the
// default type for non-terminals.

%ifndef SQLITE_OMIT_SUBQUERY
  seltablist(A) ::= stl_prefix(X) LP select(S) RP
                    as(Z) on_opt(N) using_opt(U). {
    A = sqlite3SrcListAppendFromTerm(pParse,X,0,0,&Z,S,N,U);
  }
  seltablist(A) ::= stl_prefix(X) LP seltablist(F) RP
                    as(Z) on_opt(N) using_opt(U). {
    if( X==0 && Z.n==0 && N==0 && U==0 ){


      A = F;
    }else{
      Select *pSubquery;
      sqlite3SrcListShiftJoinType(F);
      pSubquery = sqlite3SelectNew(pParse,0,F,0,0,0,0,0,0,0);
      A = sqlite3SrcListAppendFromTerm(pParse,X,0,0,&Z,pSubquery,N,U);
    }

  A = Y;
}
trigger_cmd_list(A) ::= trigger_cmd(X) SEMI. { 
  assert( X!=0 );
  X->pLast = X;
  A = X;
}

// Disallow qualified table names on INSERT, UPDATE, and DELETE statements
// within a trigger.  The table to INSERT, UPDATE, or DELETE is always in 
// the same database as the table that the trigger fires on.
//
%type trnm {Token}
trnm(A) ::= nm(X).   {A = X;}
trnm(A) ::= nm DOT nm(X). {
  A = X;
  sqlite3ErrorMsg(pParse, 
        "qualified table names are not allowed on INSERT, UPDATE, and DELETE "
        "statements within triggers");
}

// Disallow the INDEX BY and NOT INDEXED clauses on UPDATE and DELETE
// statements within triggers.  We make a specific error message for this
// since it is an exception to the default grammar rules.
//
tridxby ::= .
tridxby ::= INDEXED BY nm. {
  sqlite3ErrorMsg(pParse,
        "the INDEXED BY clause is not allowed on UPDATE or DELETE statements "
        "within triggers");
}
tridxby ::= NOT INDEXED. {
  sqlite3ErrorMsg(pParse,
        "the NOT INDEXED clause is not allowed on UPDATE or DELETE statements "
        "within triggers");
}



%type trigger_cmd {TriggerStep*}
%destructor trigger_cmd {sqlite3DeleteTriggerStep(pParse->db, $$);}
// UPDATE 
trigger_cmd(A) ::=
   UPDATE orconf(R) trnm(X) tridxby SET setlist(Y) where_opt(Z).  
   { A = sqlite3TriggerUpdateStep(pParse->db, &X, Y, Z, R); }

// INSERT
trigger_cmd(A) ::=
   insert_cmd(R) INTO trnm(X) inscollist_opt(F) VALUES LP itemlist(Y) RP.  
   {A = sqlite3TriggerInsertStep(pParse->db, &X, F, Y, 0, R);}

trigger_cmd(A) ::= insert_cmd(R) INTO trnm(X) inscollist_opt(F) select(S).
               {A = sqlite3TriggerInsertStep(pParse->db, &X, F, 0, S, R);}

// DELETE
trigger_cmd(A) ::= DELETE FROM trnm(X) tridxby where_opt(Y).
               {A = sqlite3TriggerDeleteStep(pParse->db, &X, Y);}

// SELECT
trigger_cmd(A) ::= select(X).  {A = sqlite3TriggerSelectStep(pParse->db, X); }

// The special RAISE expression that may occur in trigger programs
expr(A) ::= RAISE(X) LP IGNORE RP(Y).  {

/*
** 2003 April 6
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.214 2009/07/02 07:47:33 danielk1977 Exp $
*/
#include "sqliteInt.h"

/* Ignore this whole file if pragmas are disabled
*/
#if !defined(SQLITE_OMIT_PRAGMA)

  ** database file.  The cache size is actually the absolute value of
  ** this memory location.  The sign of meta-value 2 determines the
  ** synchronous setting.  A negative value means synchronous is off
  ** and a positive value means synchronous is on.
  */
  if( sqlite3StrICmp(zLeft,"default_cache_size")==0 ){
    static const VdbeOpList getCacheSize[] = {
      { OP_Transaction, 0, 0,        0},                         /* 0 */
      { OP_ReadCookie,  0, 1,        BTREE_DEFAULT_CACHE_SIZE},  /* 1 */
      { OP_IfPos,       1, 7,        0},
      { OP_Integer,     0, 2,        0},
      { OP_Subtract,    1, 2,        1},
      { OP_IfPos,       1, 7,        0},
      { OP_Integer,     0, 1,        0},                         /* 6 */
      { OP_ResultRow,   1, 1,        0},
    };
    int addr;
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    sqlite3VdbeUsesBtree(v, iDb);
    if( !zRight ){
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cache_size", SQLITE_STATIC);
      pParse->nMem += 2;
      addr = sqlite3VdbeAddOpList(v, ArraySize(getCacheSize), getCacheSize);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+1, iDb);
      sqlite3VdbeChangeP1(v, addr+6, SQLITE_DEFAULT_CACHE_SIZE);
    }else{
      int size = atoi(zRight);
      if( size<0 ) size = -size;
      sqlite3BeginWriteOperation(pParse, 0, iDb);
      sqlite3VdbeAddOp2(v, OP_Integer, size, 1);
      sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, 2, BTREE_DEFAULT_CACHE_SIZE);
      addr = sqlite3VdbeAddOp2(v, OP_IfPos, 2, 0);

      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+1, atoi(zRight));
      sqlite3VdbeChangeP1(v, addr+2, iDb);
      sqlite3VdbeChangeP2(v, addr+2, iCookie);
    }else{
      /* Read the specified cookie value */
      static const VdbeOpList readCookie[] = {
        { OP_Transaction,     0,  0,  0},    /* 0 */
        { OP_ReadCookie,      0,  1,  0},    /* 1 */
        { OP_ResultRow,       1,  1,  0}
      };
      int addr = sqlite3VdbeAddOpList(v, ArraySize(readCookie), readCookie);
      sqlite3VdbeChangeP1(v, addr, iDb);
      sqlite3VdbeChangeP1(v, addr+1, iDb);
      sqlite3VdbeChangeP3(v, addr+1, iCookie);
      sqlite3VdbeSetNumCols(v, 1);
      sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLeft, SQLITE_TRANSIENT);
    }
  }else
#endif /* SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS */

#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)

**    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 1.128 2009/07/03 19:19:50 drh Exp $
*/
#include "sqliteInt.h"

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

    rc = sqlite3_exec(db, argv[2], 0, 0, &zErr);
    db->init.iDb = 0;
    assert( rc!=SQLITE_OK || zErr==0 );
    if( SQLITE_OK!=rc ){
      pData->rc = rc;
      if( rc==SQLITE_NOMEM ){
        db->mallocFailed = 1;
      }else if( rc!=SQLITE_INTERRUPT && rc!=SQLITE_LOCKED ){
        corruptSchema(pData, argv[0], zErr);
      }
      sqlite3DbFree(db, zErr);
    }
  }else if( argv[0]==0 ){
    corruptSchema(pData, 0, 0);
  }else{

** database.  iDb==1 should never be used.  iDb>=2 is used for
** auxiliary databases.  Return one of the SQLITE_ error codes to
** indicate success or failure.
*/
static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
  int rc;
  int i;

  int size;
  Table *pTab;
  Db *pDb;
  char const *azArg[4];
  int meta[5];
  InitData initData;
  char const *zMasterSchema;
  char const *zMasterName = SCHEMA_TABLE(iDb);
  int openedTransaction = 0;

  /*
  ** The master database table has a structure like this
  */
  static const char master_schema[] = 
     "CREATE TABLE sqlite_master(\n"
     "  type text,\n"

  pDb = &db->aDb[iDb];
  if( pDb->pBt==0 ){
    if( !OMIT_TEMPDB && ALWAYS(iDb==1) ){
      DbSetProperty(db, 1, DB_SchemaLoaded);
    }
    return SQLITE_OK;
  }





  /* If there is not already a read-only (or read-write) transaction opened
  ** on the b-tree database, open one now. If a transaction is opened, it 
  ** will be closed before this function returns.  */
  sqlite3BtreeEnter(pDb->pBt);
  if( !sqlite3BtreeIsInReadTrans(pDb->pBt) ){
    rc = sqlite3BtreeBeginTrans(pDb->pBt, 0);
    if( rc!=SQLITE_OK ){
      sqlite3SetString(pzErrMsg, db, "%s", sqlite3ErrStr(rc));
      goto initone_error_out;
    }
    openedTransaction = 1;
  }

  /* Get the database meta information.
  **
  ** Meta values are as follows:
  **    meta[0]   Schema cookie.  Changes with each schema change.
  **    meta[1]   File format of schema layer.
  **    meta[2]   Size of the page cache.
  **    meta[3]   Largest rootpage (auto/incr_vacuum mode)
  **    meta[4]   Db text encoding. 1:UTF-8 2:UTF-16LE 3:UTF-16BE
  **    meta[5]   User version
  **    meta[6]   Incremental vacuum mode
  **    meta[7]   unused
  **    meta[8]   unused
  **    meta[9]   unused
  **
  ** Note: The #defined SQLITE_UTF* symbols in sqliteInt.h correspond to
  ** the possible values of meta[4].
  */
  for(i=0; i<ArraySize(meta); i++){
    sqlite3BtreeGetMeta(pDb->pBt, i+1, (u32 *)&meta[i]);




  }
  pDb->pSchema->schema_cookie = meta[BTREE_SCHEMA_VERSION-1];

  /* If opening a non-empty database, check the text encoding. For the
  ** main database, set sqlite3.enc to the encoding of the main database.
  ** For an attached db, it is an error if the encoding is not the same
  ** as sqlite3.enc.

  }

  /* Jump here for an error that occurs after successfully allocating
  ** curMain and calling sqlite3BtreeEnter(). For an error that occurs
  ** before that point, jump to error_out.
  */
initone_error_out:
  if( openedTransaction ){
    sqlite3BtreeCommit(pDb->pBt);

  }
  sqlite3BtreeLeave(pDb->pBt);

error_out:
  if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
    db->mallocFailed = 1;
  }
  return rc;

  }
  return rc;
}


/*
** Check schema cookies in all databases.  If any cookie is out
** of date set pParse->rc to SQLITE_SCHEMA.  If all schema cookies
** make no changes to pParse->rc.
*/
static void schemaIsValid(Parse *pParse){
  sqlite3 *db = pParse->db;
  int iDb;
  int rc;

  int cookie;


  assert( pParse->checkSchema );

  assert( sqlite3_mutex_held(db->mutex) );
  for(iDb=0; iDb<db->nDb; iDb++){

    int openedTransaction = 0;         /* True if a transaction is opened */
    Btree *pBt = db->aDb[iDb].pBt;     /* Btree database to read cookie from */
    if( pBt==0 ) continue;

    /* If there is not already a read-only (or read-write) transaction opened
    ** on the b-tree database, open one now. If a transaction is opened, it 
    ** will be closed immediately after reading the meta-value. */
    if( !sqlite3BtreeIsInReadTrans(pBt) ){
      rc = sqlite3BtreeBeginTrans(pBt, 0);
      if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
        db->mallocFailed = 1;
      }
      if( rc!=SQLITE_OK ) return;

      openedTransaction = 1;
    }


    /* Read the schema cookie from the database. If it does not match the 
    ** value stored as part of the in the in-memory schema representation,
    ** set Parse.rc to SQLITE_SCHEMA. */
    sqlite3BtreeGetMeta(pBt, BTREE_SCHEMA_VERSION, (u32 *)&cookie);
    if( cookie!=db->aDb[iDb].pSchema->schema_cookie ){
      pParse->rc = SQLITE_SCHEMA;
    }

    /* Close the transaction, if one was opened. */
    if( openedTransaction ){
      sqlite3BtreeCommit(pBt);



    }
  }

}

/*
** 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

    sqlite3RunParser(pParse, zSql, &zErrMsg);
  }

  if( db->mallocFailed ){
    pParse->rc = SQLITE_NOMEM;
  }
  if( pParse->rc==SQLITE_DONE ) pParse->rc = SQLITE_OK;
  if( pParse->checkSchema ){
    schemaIsValid(pParse);
  }
  if( pParse->rc==SQLITE_SCHEMA ){
    sqlite3ResetInternalSchema(db, 0);
  }
  if( db->mallocFailed ){
    pParse->rc = SQLITE_NOMEM;
  }

/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.892 2009/07/03 22:54:37 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build

** be true and false so that the unreachable code then specify will
** not be counted as untested code.
*/
#if defined(SQLITE_COVERAGE_TEST)
# define ALWAYS(X)      (1)
# define NEVER(X)       (0)
#elif !defined(NDEBUG)

# define ALWAYS(X)      ((X)?1:(assert(0),0))
# define NEVER(X)       ((X)?(assert(0),1):0)
#else
# define ALWAYS(X)      (X)
# define NEVER(X)       (X)
#endif

/*
** The macro unlikely() is a hint that surrounds a boolean

#define UNUSED_PARAMETER2(x,y) UNUSED_PARAMETER(x),UNUSED_PARAMETER(y)

/*
** Forward references to structures
*/
typedef struct AggInfo AggInfo;
typedef struct AuthContext AuthContext;
typedef struct AutoincInfo AutoincInfo;
typedef struct Bitvec Bitvec;
typedef struct RowSet RowSet;
typedef struct CollSeq CollSeq;
typedef struct Column Column;
typedef struct Db Db;
typedef struct Schema Schema;
typedef struct Expr Expr;

  u8 dfltLockMode;              /* Default locking-mode for attached dbs */
  u8 dfltJournalMode;           /* Default journal mode for attached dbs */
  signed char nextAutovac;      /* Autovac setting after VACUUM if >=0 */
  int nextPagesize;             /* Pagesize after VACUUM if >0 */
  int nTable;                   /* Number of tables in the database */
  CollSeq *pDfltColl;           /* The default collating sequence (BINARY) */
  i64 lastRowid;                /* ROWID of most recent insert (see above) */

  u32 magic;                    /* Magic number for detect library misuse */
  int nChange;                  /* Value returned by sqlite3_changes() */
  int nTotalChange;             /* Value returned by sqlite3_total_changes() */
  sqlite3_mutex *mutex;         /* Connection mutex */
  int aLimit[SQLITE_N_LIMIT];   /* Limits */
  struct sqlite3InitInfo {      /* Information used during initialization */
    int iDb;                    /* When back is being initialized */

  u8 eDest;         /* How to dispose of the results */
  u8 affinity;      /* Affinity used when eDest==SRT_Set */
  int iParm;        /* A parameter used by the eDest disposal method */
  int iMem;         /* Base register where results are written */
  int nMem;         /* Number of registers allocated */
};

/*
** During code generation of statements that do inserts into AUTOINCREMENT 
** tables, the following information is attached to the Table.u.autoInc.p
** pointer of each autoincrement table to record some side information that
** the code generator needs.  We have to keep per-table autoincrement
** information in case inserts are down within triggers.  Triggers do not
** normally coordinate their activities, but we do need to coordinate the
** loading and saving of autoincrement information.
*/
struct AutoincInfo {
  AutoincInfo *pNext;   /* Next info block in a list of them all */
  Table *pTab;          /* Table this info block refers to */
  int iDb;              /* Index in sqlite3.aDb[] of database holding pTab */
  int regCtr;           /* Memory register holding the rowid counter */
};

/*
** Size of the column cache
*/
#ifndef SQLITE_N_COLCACHE
# define SQLITE_N_COLCACHE 10
#endif

  int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
#ifndef SQLITE_OMIT_SHARED_CACHE
  int nTableLock;        /* Number of locks in aTableLock */
  TableLock *aTableLock; /* Required table locks for shared-cache mode */
#endif
  int regRowid;        /* Register holding rowid of CREATE TABLE entry */
  int regRoot;         /* Register holding root page number for new objects */
  AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */

  /* Above is constant between recursions.  Below is reset before and after
  ** each recursion */

  int nVar;            /* Number of '?' variables seen in the SQL so far */
  int nVarExpr;        /* Number of used slots in apVarExpr[] */
  int nVarExprAlloc;   /* Number of allocated slots in apVarExpr[] */
  Expr **apVarExpr;    /* Pointers to :aaa and $aaaa wildcard expressions */
  int nAlias;          /* Number of aliased result set columns */
  int nAliasAlloc;     /* Number of allocated slots for aAlias[] */
  int *aAlias;         /* Register used to hold aliased result */
  u8 explain;          /* True if the EXPLAIN flag is found on the query */

  Token sNameToken;    /* Token with unqualified schema object name */
  Token sLastToken;    /* The last token parsed */

  const char *zTail;   /* All SQL text past the last semicolon parsed */
  Table *pNewTable;    /* A table being constructed by CREATE TABLE */
  Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
  TriggerStack *trigStack;  /* Trigger actions being coded */
  const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  Token sArg;                /* Complete text of a module argument */

 *              Otherwise NULL.
 * pExprList -> A list of the columns to update and the expressions to update
 *              them to. See sqlite3Update() documentation of "pChanges"
 *              argument.
 * 
 */
struct TriggerStep {
  u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
  u8 orconf;           /* OE_Rollback etc. */
  Trigger *pTrig;      /* The trigger that this step is a part of */

  Select *pSelect;     /* SELECT statment or RHS of INSERT INTO .. SELECT ... */

  Token target;        /* Target table for DELETE, UPDATE, INSERT */
  Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
  ExprList *pExprList; /* SET clause for UPDATE.  VALUES clause for INSERT */

  IdList *pIdList;     /* Column names for INSERT */
  TriggerStep *pNext;  /* Next in the link-list */
  TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
};

/*
 * An instance of struct TriggerStack stores information required during code
 * generation of a single trigger program. While the trigger program is being

  int sqlite3ViewGetColumnNames(Parse*,Table*);
#else
# define sqlite3ViewGetColumnNames(A,B) 0
#endif

void sqlite3DropTable(Parse*, SrcList*, int, int);
void sqlite3DeleteTable(Table*);
#ifndef SQLITE_OMIT_AUTOINCREMENT
  void sqlite3AutoincrementBegin(Parse *pParse);
  void sqlite3AutoincrementEnd(Parse *pParse);
#else
# define sqlite3AutoincrementBegin(X)
# define sqlite3AutoincrementEnd(X)
#endif
void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
void *sqlite3ArrayAllocate(sqlite3*,void*,int,int,int*,int*,int*);
IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
int sqlite3IdListIndex(IdList*,const char*);
SrcList *sqlite3SrcListEnlarge(sqlite3*, SrcList*, int, int);
SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** A TCL Interface to SQLite.  Append this file to sqlite3.c and
** compile the whole thing to build a TCL-enabled version of SQLite.
**
** $Id: tclsqlite.c,v 1.242 2009/07/03 22:54:37 drh Exp $
*/
#include "tcl.h"
#include <errno.h>

/*
** Some additional include files are needed if this file is not
** appended to the amalgamation.

      Tcl_Obj **apColName = 0;   /* Array of column names */
      int len;                   /* String length of zSql */
  
      /* Try to find a SQL statement that has already been compiled and
      ** which matches the next sequence of SQL.
      */
      pStmt = 0;
      while( isspace(zSql[0]) ){ zSql++; }
      len = strlen30(zSql);
      for(pPreStmt = pDb->stmtList; pPreStmt; pPreStmt=pPreStmt->pNext){
        int n = pPreStmt->nSql;
        if( len>=n 
            && memcmp(pPreStmt->zSql, zSql, n)==0
            && (zSql[n]==0 || zSql[n-1]==';')
        ){

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the btree.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test3.c,v 1.108 2009/07/06 18:56:13 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "btreeInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>

static int btree_get_meta(
  void *NotUsed,
  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
  int argc,              /* Number of arguments */
  const char **argv      /* Text of each argument */
){
  Btree *pBt;

  int i;
  if( argc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " ID\"", 0);
    return TCL_ERROR;
  }
  pBt = sqlite3TestTextToPtr(argv[1]);
  for(i=0; i<SQLITE_N_BTREE_META; i++){
    char zBuf[30];
    u32 v;
    sqlite3BtreeEnter(pBt);
    sqlite3BtreeGetMeta(pBt, i, &v);
    sqlite3BtreeLeave(pBt);




    sqlite3_snprintf(sizeof(zBuf), zBuf,"%d",v);
    Tcl_AppendElement(interp, zBuf);
  }
  return TCL_OK;
}

/*

  }
  pBt = sqlite3TestTextToPtr(argv[1]);
  if( Tcl_GetInt(interp, argv[2], &iTable) ) return TCL_ERROR;
  if( Tcl_GetBoolean(interp, argv[3], &wrFlag) ) return TCL_ERROR;
  pCur = (BtCursor *)ckalloc(sqlite3BtreeCursorSize());
  memset(pCur, 0, sqlite3BtreeCursorSize());
  sqlite3BtreeEnter(pBt);
  rc = sqlite3BtreeLockTable(pBt, iTable, wrFlag);
  if( rc==SQLITE_OK ){
    rc = sqlite3BtreeCursor(pBt, iTable, wrFlag, 0, pCur);
  }
  sqlite3BtreeLeave(pBt);
  if( rc ){
    ckfree((char *)pCur);
    Tcl_AppendResult(interp, errorName(rc), 0);
    return TCL_ERROR;
  }
  sqlite3_snprintf(sizeof(zBuf), zBuf,"%p", pCur);

    int iKey;
    if( Tcl_GetInt(interp, argv[2], &iKey) ){
      sqlite3BtreeLeave(pCur->pBtree);
      return TCL_ERROR;
    }
    rc = sqlite3BtreeMovetoUnpacked(pCur, 0, iKey, 0, &res);
  }else{
#if 0
    rc = sqlite3BtreeMoveto(pCur, argv[2], strlen(argv[2]), 0, &res);  
#endif
  }
  sqlite3BtreeLeave(pCur->pBtree);
  if( rc ){
    Tcl_AppendResult(interp, errorName(rc), 0);
    return TCL_ERROR;
  }
  if( res<0 ) res = -1;

******************************************************************************
**
** This file contains code for a VFS layer that acts as a wrapper around
** an existing VFS. The code in this file attempts to verify that SQLite
** correctly populates and syncs a journal file before writing to a
** corresponding database file.
**
** $Id: test_journal.c,v 1.17 2009/06/26 10:39:36 danielk1977 Exp $
*/
#if SQLITE_TEST          /* This file is used for testing only */

#include "sqlite3.h"
#include "sqliteInt.h"

/*

  sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_PRNG));
}
static void leaveJtMutex(void){
  sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_PRNG));
}

extern int sqlite3_io_error_pending;
extern int sqlite3_io_error_hit;
static void stop_ioerr_simulation(int *piSave, int *piSave2){
  *piSave = sqlite3_io_error_pending;
  *piSave2 = sqlite3_io_error_hit;
  sqlite3_io_error_pending = -1;
  sqlite3_io_error_hit = 0;
}
static void start_ioerr_simulation(int iSave, int iSave2){
  sqlite3_io_error_pending = iSave;
  sqlite3_io_error_hit = iSave2;
}

/*
** The jt_file pointed to by the argument may or may not be a file-handle
** open on a main database file. If it is, and a transaction is currently
** opened on the file, then discard all transaction related data.
*/

  pJournal->iMaxOff = 0;

  if( !pMain->pWritable || !pMain->aCksum || !aData ){
    rc = SQLITE_IOERR_NOMEM;
  }else if( pMain->nPage>0 ){
    u32 iTrunk;
    int iSave;
    int iSave2;

    stop_ioerr_simulation(&iSave, &iSave2);

    /* Read the database free-list. Add the page-number for each free-list
    ** leaf to the jt_file.pWritable bitvec.
    */
    rc = sqlite3OsRead(p, aData, pMain->nPagesize, 0);
    iTrunk = decodeUint32(&aData[32]);
    while( rc==SQLITE_OK && iTrunk>0 ){

        i64 iOff = (i64)(pMain->nPagesize) * (i64)ii;
        if( iOff==PENDING_BYTE ) continue;
        rc = sqlite3OsRead(pMain->pReal, aData, pMain->nPagesize, iOff);
        pMain->aCksum[ii] = genCksum(aData, pMain->nPagesize);
      }
    }

    start_ioerr_simulation(iSave, iSave2);
  }

  sqlite3_free(aData);
  return rc;
}












































































/*
** The first argument to this function is a handle open on a journal file.
** This function reads the journal file and adds the page number for each
** page in the journal to the Bitvec object passed as the second argument.
*/
static int readJournalFile(jt_file *p, jt_file *pMain){
  int rc = SQLITE_OK;
  unsigned char zBuf[28];
  sqlite3_file *pReal = p->pReal;
  sqlite3_int64 iOff = 0;
  sqlite3_int64 iSize = p->iMaxOff;
  unsigned char *aPage;
  int iSave;
  int iSave2;

  aPage = sqlite3_malloc(pMain->nPagesize);
  if( !aPage ){
    return SQLITE_IOERR_NOMEM;
  }

  stop_ioerr_simulation(&iSave, &iSave2);

  while( rc==SQLITE_OK && iOff<iSize ){
    u32 nRec, nPage, nSector, nPagesize;
    u32 ii;

    /* Read and decode the next journal-header from the journal file. */
    rc = sqlite3OsRead(pReal, zBuf, 28, iOff);

      }
    }

    iOff = ((iOff + (nSector-1)) / nSector) * nSector;
  }

finish_rjf:
  start_ioerr_simulation(iSave, iSave2);
  sqlite3_free(aPage);
  if( rc==SQLITE_IOERR_SHORT_READ ){
    rc = SQLITE_OK;
  }
  return rc;
}


/*
** Write data to an jt-file.
*/
static int jtWrite(
  sqlite3_file *pFile, 
  const void *zBuf, 
  int iAmt, 
  sqlite_int64 iOfst
){
  int rc;
  jt_file *p = (jt_file *)pFile;
  if( p->flags&SQLITE_OPEN_MAIN_JOURNAL ){
    if( iOfst==0 ){
      jt_file *pMain = locateDatabaseHandle(p->zName);
      assert( pMain );
  
      if( iAmt==28 ){
        /* Zeroing the first journal-file header. This is the end of a
        ** transaction. */
        closeTransaction(pMain);
      }else if( iAmt!=12 ){
        /* Writing the first journal header to a journal file. This happens
        ** when a transaction is first started.  */
        u8 *z = (u8 *)zBuf;
        pMain->nPage = decodeUint32(&z[16]);
        pMain->nPagesize = decodeUint32(&z[24]);
        if( SQLITE_OK!=(rc=openTransaction(pMain, p)) ){
          return rc;
        }
      }
    }
    if( p->iMaxOff<(iOfst + iAmt) ){
      p->iMaxOff = iOfst + iAmt;
    }
  }

  if( p->flags&SQLITE_OPEN_MAIN_DB && p->pWritable ){
    if( iAmt<p->nPagesize 
     && p->nPagesize%iAmt==0 
     && iOfst>=(PENDING_BYTE+512) 
     && iOfst+iAmt<=PENDING_BYTE+p->nPagesize
    ){
      /* No-op. This special case is hit when the backup code is copying a
      ** to a database with a larger page-size than the source database and
      ** it needs to fill in the non-locking-region part of the original
      ** pending-byte page.
      */
    }else{
      u32 pgno = iOfst/p->nPagesize + 1;
      assert( (iAmt==1||iAmt==p->nPagesize) && ((iOfst+iAmt)%p->nPagesize)==0 );
      assert( pgno<=p->nPage || p->nSync>0 );
      assert( pgno>p->nPage || sqlite3BitvecTest(p->pWritable, pgno) );
    }
  }

  rc = sqlite3OsWrite(p->pReal, zBuf, iAmt, iOfst);
  if( (p->flags&SQLITE_OPEN_MAIN_JOURNAL) && iAmt==12 ){
    jt_file *pMain = locateDatabaseHandle(p->zName);
    int rc2 = readJournalFile(p, pMain);
    if( rc==SQLITE_OK ) rc = rc2;
  }
  return rc;
}

/*
** Truncate an jt-file.
*/
static int jtTruncate(sqlite3_file *pFile, sqlite_int64 size){
  jt_file *p = (jt_file *)pFile;
  if( p->flags&SQLITE_OPEN_MAIN_JOURNAL && size==0 ){
    /* Truncating a journal file. This is the end of a transaction. */
    jt_file *pMain = locateDatabaseHandle(p->zName);
    closeTransaction(pMain);
  }
  if( p->flags&SQLITE_OPEN_MAIN_DB && p->pWritable ){
    u32 pgno;
    u32 locking_page = (u32)(PENDING_BYTE/p->nPagesize+1);
    for(pgno=size/p->nPagesize+1; pgno<=p->nPage; pgno++){
      assert( pgno==locking_page || sqlite3BitvecTest(p->pWritable, pgno) );
    }
  }
  return sqlite3OsTruncate(p->pReal, size);
}

/*
** Sync an jt-file.
*/
static int jtSync(sqlite3_file *pFile, int flags){
  jt_file *p = (jt_file *)pFile;

  if( p->flags&SQLITE_OPEN_MAIN_JOURNAL ){

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement test interfaces to the
** memory allocation subsystem.
**
** $Id: test_malloc.c,v 1.55 2009/07/01 18:09:02 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>

  if( TCL_OK!=Tcl_GetBooleanFromObj(interp, objv[1], &isInstall) ){
    return TCL_ERROR;
  }
  rc = faultsimInstall(isInstall);
  Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_VOLATILE);
  return TCL_OK;
}

/*
** sqlite3_install_memsys3
*/
static int test_install_memsys3(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  int rc = SQLITE_MISUSE;
#ifdef SQLITE_ENABLE_MEMSYS3
  const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
  rc = sqlite3_config(SQLITE_CONFIG_MALLOC, sqlite3MemGetMemsys3());
#endif
  Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_VOLATILE);
  return TCL_OK;
}

/*
** Register commands with the TCL interpreter.
*/
int Sqlitetest_malloc_Init(Tcl_Interp *interp){
  static struct {
     char *zName;

     { "sqlite3_config_heap",        test_config_heap              ,0 },
     { "sqlite3_config_memstatus",   test_config_memstatus         ,0 },
     { "sqlite3_config_lookaside",   test_config_lookaside         ,0 },
     { "sqlite3_config_error",       test_config_error             ,0 },
     { "sqlite3_db_config_lookaside",test_db_config_lookaside      ,0 },
     { "sqlite3_dump_memsys3",       test_dump_memsys3             ,3 },
     { "sqlite3_dump_memsys5",       test_dump_memsys3             ,5 },
     { "sqlite3_install_memsys3",    test_install_memsys3          ,0 },
  };
  int i;
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    ClientData c = (ClientData)aObjCmd[i].clientData;
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, aObjCmd[i].xProc, c, 0);
  }
  return TCL_OK;
}
#endif

*************************************************************************
** An tokenizer for SQL
**
** This file contains C code that splits an SQL input string up into
** individual tokens and sends those tokens one-by-one over to the
** parser for analysis.
**
** $Id: tokenize.c,v 1.163 2009/07/03 22:54:37 drh Exp $
*/
#include "sqliteInt.h"
#include <stdlib.h>

/*
** The charMap() macro maps alphabetic characters into their
** lower-case ASCII equivalent.  On ASCII machines, this is just

  mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
  if( db->activeVdbeCnt==0 ){
    db->u1.isInterrupted = 0;
  }
  pParse->rc = SQLITE_OK;
  pParse->zTail = zSql;
  i = 0;
  assert( pzErrMsg!=0 );
  pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3Malloc);
  if( pEngine==0 ){
    db->mallocFailed = 1;
    return SQLITE_NOMEM;
  }

    */
    sqlite3DeleteTable(pParse->pNewTable);
  }

  sqlite3DeleteTrigger(db, pParse->pNewTrigger);
  sqlite3DbFree(db, pParse->apVarExpr);
  sqlite3DbFree(db, pParse->aAlias);
  while( pParse->pAinc ){
    AutoincInfo *p = pParse->pAinc;
    pParse->pAinc = p->pNext;
    sqlite3DbFree(db, p);
  }
  while( pParse->pZombieTab ){
    Table *p = pParse->pZombieTab;
    pParse->pZombieTab = p->pNextZombie;
    sqlite3DeleteTable(p);
  }
  if( nErr>0 && pParse->rc==SQLITE_OK ){
    pParse->rc = SQLITE_ERROR;
  }
  return nErr;
}

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle UPDATE statements.
**
** $Id: update.c,v 1.204 2009/06/27 11:17:35 drh Exp $
*/
#include "sqliteInt.h"

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Forward declaration */
static void updateVirtualTable(
  Parse *pParse,       /* The parsing context */

    }
  }
  sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
  if( pTrigger ){
    sqlite3VdbeAddOp2(v, OP_Close, newIdx, 0);
    sqlite3VdbeAddOp2(v, OP_Close, oldIdx, 0);
  }

  /* Update the sqlite_sequence table by storing the content of the
  ** maximum rowid counter values recorded while inserting into
  ** autoincrement tables.
  */
  if( pParse->nested==0 && pParse->trigStack==0 ){
    sqlite3AutoincrementEnd(pParse);
  }

  /*
  ** Return the number of rows that were changed. If this routine is 
  ** generating code because of a call to sqlite3NestedParse(), do not
  ** invoke the callback function.
  */
  if( db->flags & SQLITE_CountRows && !pParse->trigStack && pParse->nested==0 ){

  */
  sqlite3SelectDestInit(&dest, SRT_Table, ephemTab);
  sqlite3Select(pParse, pSelect, &dest);

  /* Generate code to scan the ephemeral table and call VUpdate. */
  iReg = ++pParse->nMem;
  pParse->nMem += pTab->nCol+1;
  addr = sqlite3VdbeAddOp2(v, OP_Rewind, ephemTab, 0);

  sqlite3VdbeAddOp3(v, OP_Column,  ephemTab, 0, iReg);
  sqlite3VdbeAddOp3(v, OP_Column, ephemTab, (pRowid?1:0), iReg+1);
  for(i=0; i<pTab->nCol; i++){
    sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i);
  }
  sqlite3VtabMakeWritable(pParse, pTab);
  sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVtab, P4_VTAB);
  sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1);
  sqlite3VdbeJumpHere(v, addr);
  sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);

  /* Cleanup */
  sqlite3SelectDelete(db, pSelect);  
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

/* Make sure "isView" gets undefined in case this file becomes part of
** the amalgamation - so that subsequent files do not see isView as a
** macro. */
#undef isView

**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.261 2009/06/24 10:26:33 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#ifdef SQLITE_HAVE_ISNAN
# include <math.h>
#endif

/*
** Routine needed to support the testcase() macro.
*/
#ifdef SQLITE_COVERAGE_TEST
void sqlite3Coverage(int x){
  static int dummy = 0;
  dummy += x;
}





















#endif

/*
** Return true if the floating point value is Not a Number (NaN).
**
** Use the math library isnan() function if compiled with SQLITE_HAVE_ISNAN.
** Otherwise, we have our own implementation that works on most systems.

**
*************************************************************************
** This file contains code used to implement the VACUUM command.
**
** Most of the code in this file may be omitted by defining the
** SQLITE_OMIT_VACUUM macro.
**
** $Id: vacuum.c,v 1.91 2009/07/02 07:47:33 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
/*
** Execute zSql on database db. Return an error code.

    assert( 1==sqlite3BtreeIsInTrans(pTemp) );
    assert( 1==sqlite3BtreeIsInTrans(pMain) );

    /* Copy Btree meta values */
    for(i=0; i<ArraySize(aCopy); i+=2){
      /* GetMeta() and UpdateMeta() cannot fail in this context because
      ** we already have page 1 loaded into cache and marked dirty. */
      sqlite3BtreeGetMeta(pMain, aCopy[i], &meta);

      rc = sqlite3BtreeUpdateMeta(pTemp, aCopy[i], meta+aCopy[i+1]);
      if( NEVER(rc!=SQLITE_OK) ) goto end_of_vacuum;
    }

    rc = sqlite3BtreeCopyFile(pMain, pTemp);
    if( rc!=SQLITE_OK ) goto end_of_vacuum;
    rc = sqlite3BtreeCommit(pTemp);

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.869 2009/07/03 16:25:07 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_SeekXX, OP_Next, or OP_Prev opcodes.  The test

** There is an implied "Halt 0 0 0" instruction inserted at the very end of
** every program.  So a jump past the last instruction of the program
** is the same as executing Halt.
*/
case OP_Halt: {
  p->rc = pOp->p1;
  p->pc = pc;
  p->errorAction = (u8)pOp->p2;
  if( pOp->p4.z ){
    sqlite3SetString(&p->zErrMsg, db, "%s", pOp->p4.z);
  }
  rc = sqlite3VdbeHalt(p);
  assert( rc==SQLITE_BUSY || rc==SQLITE_OK );
  if( rc==SQLITE_BUSY ){
    p->rc = rc = SQLITE_BUSY;

  p2 = pOp->p2;
  pC = 0;
  memset(&sMem, 0, sizeof(sMem));
  assert( p1<p->nCursor );
  assert( pOp->p3>0 && pOp->p3<=p->nMem );
  pDest = &p->aMem[pOp->p3];
  MemSetTypeFlag(pDest, MEM_Null);
  zRec = 0;

  /* This block sets the variable payloadSize to be the total number of
  ** bytes in the record.
  **
  ** zRec is set to be the complete text of the record if it is available.
  ** The complete record text is always available for pseudo-tables
  ** If the record is stored in a cursor, the complete record text
  ** might be available in the  pC->aRow cache.  Or it might not be.
  ** If the data is unavailable,  zRec is set to NULL.
  **
  ** We also compute the number of columns in the record.  For cursors,
  ** the number of columns is stored in the VdbeCursor.nField element.
  */
  pC = p->apCsr[p1];
  assert( pC!=0 );
#ifndef SQLITE_OMIT_VIRTUALTABLE
  assert( pC->pVtabCursor==0 );
#endif
  pCrsr = pC->pCursor;
  if( pCrsr!=0 ){
    /* The record is stored in a B-Tree */
    rc = sqlite3VdbeCursorMoveto(pC);
    if( rc ) goto abort_due_to_error;


    if( pC->nullRow ){
      payloadSize = 0;
    }else if( pC->cacheStatus==p->cacheCtr ){
      payloadSize = pC->payloadSize;
      zRec = (char*)pC->aRow;
    }else if( pC->isIndex ){
      sqlite3BtreeKeySize(pCrsr, &payloadSize64);
      /* sqlite3BtreeParseCellPtr() uses getVarint32() to extract the
      ** payload size, so it is impossible for payloadSize64 to be
      ** larger than 32 bits. */
      assert( (payloadSize64 & SQLITE_MAX_U32)==(u64)payloadSize64 );
      payloadSize = (u32)payloadSize64;
    }else{
      sqlite3BtreeDataSize(pCrsr, &payloadSize);
    }

  }else if( pC->pseudoTable ){
    /* The record is the sole entry of a pseudo-table */
    payloadSize = pC->nData;
    zRec = pC->pData;
    pC->cacheStatus = CACHE_STALE;
    assert( payloadSize==0 || zRec!=0 );


  }else{
    /* Consider the row to be NULL */
    payloadSize = 0;
  }

  /* If payloadSize is 0, then just store a NULL */
  if( payloadSize==0 ){
    assert( pDest->flags&MEM_Null );
    goto op_column_out;
  }
  assert( db->aLimit[SQLITE_LIMIT_LENGTH]>=0 );
  if( payloadSize > (u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
    goto too_big;
  }

  nField = pC->nField;
  assert( p2<nField );

  /* Read and parse the table header.  Store the results of the parse
  ** into the record header cache fields of the cursor.
  */
  aType = pC->aType;
  if( pC->cacheStatus==p->cacheCtr ){

  iDb = pOp->p1;
  iCookie = pOp->p3;
  assert( pOp->p3<SQLITE_N_BTREE_META );
  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pBt!=0 );
  assert( (p->btreeMask & (1<<iDb))!=0 );

  sqlite3BtreeGetMeta(db->aDb[iDb].pBt, iCookie, (u32 *)&iMeta);
  pOut->u.i = iMeta;
  MemSetTypeFlag(pOut, MEM_Int);
  break;
}

/* Opcode: SetCookie P1 P2 P3 * *
**

case OP_VerifyCookie: {
  int iMeta;
  Btree *pBt;
  assert( pOp->p1>=0 && pOp->p1<db->nDb );
  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
  pBt = db->aDb[pOp->p1].pBt;
  if( pBt ){
    sqlite3BtreeGetMeta(pBt, BTREE_SCHEMA_VERSION, (u32 *)&iMeta);
  }else{

    iMeta = 0;
  }
  if( iMeta!=pOp->p2 ){
    sqlite3DbFree(db, p->zErrMsg);
    p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
    /* If the schema-cookie from the database file matches the cookie 
    ** stored with the in-memory representation of the schema, do
    ** not reload the schema from the database file.
    **
    ** If virtual-tables are in use, this is not just an optimization.

#endif

      sqlite3BtreeSetCachedRowid(pC->pCursor, v<MAX_ROWID ? v+1 : 0);
    }
    if( pC->useRandomRowid ){
      assert( pOp->p3==0 );  /* We cannot be in random rowid mode if this is
                             ** an AUTOINCREMENT table. */
      v = db->lastRowid;
      cnt = 0;
      do{
        if( cnt==0 && (v&0xffffff)==v ){
          v++;
        }else{
          sqlite3_randomness(sizeof(v), &v);
          if( cnt<5 ) v &= 0xffffff;
        }
        rc = sqlite3BtreeMovetoUnpacked(pC->pCursor, 0, (u64)v, 0, &res);
        cnt++;
      }while( cnt<100 && rc==SQLITE_OK && res==0 );

      if( rc==SQLITE_OK && res==0 ){
        rc = SQLITE_FULL;
        goto abort_due_to_error;
      }
    }
    pC->rowidIsValid = 0;
    pC->deferredMoveto = 0;

  ** schema of database iDb before the SQL statement runs. The schema
  ** will not be reloaded becuase the db->init.busy flag is set. This
  ** can result in a "no such table: sqlite_master" or "malformed
  ** database schema" error being returned to the user.
  */
  assert( sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
  sqlite3BtreeEnterAll(db);
  if( pOp->p2 || DbHasProperty(db, iDb, DB_SchemaLoaded) ){
    zMaster = SCHEMA_TABLE(iDb);
    initData.db = db;
    initData.iDb = pOp->p1;
    initData.pzErrMsg = &p->zErrMsg;
    zSql = sqlite3MPrintf(db,
       "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s",
       db->aDb[iDb].zName, zMaster, pOp->p4.z);

*/
case OP_AggFinal: {
  Mem *pMem;
  assert( pOp->p1>0 && pOp->p1<=p->nMem );
  pMem = &p->aMem[pOp->p1];
  assert( (pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
  rc = sqlite3VdbeMemFinalize(pMem, pOp->p4.pFunc);
  if( rc ){
    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(pMem));
  }
  sqlite3VdbeChangeEncoding(pMem, encoding);
  UPDATE_MAX_BLOBSIZE(pMem);
  if( sqlite3VdbeMemTooBig(pMem) ){
    goto too_big;
  }

#ifndef SQLITE_OMIT_SHARED_CACHE
/* Opcode: TableLock P1 P2 P3 P4 *
**
** Obtain a lock on a particular table. This instruction is only used when
** the shared-cache feature is enabled. 
**
** P1 is the index of the database in sqlite3.aDb[] of the database
** on which the lock is acquired.  A readlock is obtained if P3==0 or
** a write lock if P3==1.
**
** P2 contains the root-page of the table to lock.
**
** P4 contains a pointer to the name of the table being locked. This is only
** used to generate an error message if the lock cannot be obtained.
*/
case OP_TableLock: {

  u8 isWriteLock = (u8)pOp->p3;
  if( isWriteLock || 0==(db->flags&SQLITE_ReadUncommitted) ){
    int p1 = pOp->p1; 

    assert( p1>=0 && p1<db->nDb );
    assert( (p->btreeMask & (1<<p1))!=0 );
    assert( isWriteLock==0 || isWriteLock==1 );
    rc = sqlite3BtreeLockTable(db->aDb[p1].pBt, pOp->p2, isWriteLock);
    if( (rc&0xFF)==SQLITE_LOCKED ){
      const char *z = pOp->p4.z;
      sqlite3SetString(&p->zErrMsg, db, "database table is locked: %s", z);
    }
  }
  break;
}
#endif /* SQLITE_OMIT_SHARED_CACHE */

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VBegin * * * P4 *

  MemSetTypeFlag(&sContext.s, MEM_Null);

  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
  rc = pModule->xColumn(pCur->pVtabCursor, &sContext, pOp->p2);
  sqlite3DbFree(db, p->zErrMsg);
  p->zErrMsg = pVtab->zErrMsg;
  pVtab->zErrMsg = 0;
  if( sContext.isError ){
    rc = sContext.isError;
  }

  /* Copy the result of the function to the P3 register. We
  ** do this regardless of whether or not an error occurred to ensure any
  ** dynamic allocation in sContext.s (a Mem struct) is  released.
  */
  sqlite3VdbeChangeEncoding(&sContext.s, encoding);
  REGISTER_TRACE(pOp->p3, pDest);

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code use to implement APIs that are part of the
** VDBE.
**
** $Id: vdbeapi.c,v 1.167 2009/06/25 01:47:12 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

#ifndef SQLITE_OMIT_DEPRECATED
/*
** Return TRUE (non-zero) of the statement supplied as an argument needs

int sqlite3_value_type(sqlite3_value* pVal){
  return pVal->type;
}

/**************************** sqlite3_result_  *******************************
** The following routines are used by user-defined functions to specify
** the function result.
**
** The setStrOrError() funtion calls sqlite3VdbeMemSetStr() to store the
** result as a string or blob but if the string or blob is too large, it
** then sets the error code to SQLITE_TOOBIG
*/
static void setResultStrOrError(
  sqlite3_context *pCtx,  /* Function context */
  const char *z,          /* String pointer */
  int n,                  /* Bytes in string, or negative */
  u8 enc,                 /* Encoding of z.  0 for BLOBs */
  void (*xDel)(void*)     /* Destructor function */
){
  if( sqlite3VdbeMemSetStr(&pCtx->s, z, n, enc, xDel)==SQLITE_TOOBIG ){
    sqlite3_result_error_toobig(pCtx);
  }
}
void sqlite3_result_blob(
  sqlite3_context *pCtx, 
  const void *z, 
  int n, 
  void (*xDel)(void *)
){
  assert( n>=0 );
  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
  setResultStrOrError(pCtx, z, n, 0, xDel);
}
void sqlite3_result_double(sqlite3_context *pCtx, double rVal){
  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
  sqlite3VdbeMemSetDouble(&pCtx->s, rVal);
}
void sqlite3_result_error(sqlite3_context *pCtx, const char *z, int n){
  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );

void sqlite3_result_text(
  sqlite3_context *pCtx, 
  const char *z, 
  int n,
  void (*xDel)(void *)
){
  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
  setResultStrOrError(pCtx, z, n, SQLITE_UTF8, xDel);
}
#ifndef SQLITE_OMIT_UTF16
void sqlite3_result_text16(
  sqlite3_context *pCtx, 
  const void *z, 
  int n, 
  void (*xDel)(void *)
){
  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
  setResultStrOrError(pCtx, z, n, SQLITE_UTF16NATIVE, xDel);
}
void sqlite3_result_text16be(
  sqlite3_context *pCtx, 
  const void *z, 
  int n, 
  void (*xDel)(void *)
){
  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
  setResultStrOrError(pCtx, z, n, SQLITE_UTF16BE, xDel);
}
void sqlite3_result_text16le(
  sqlite3_context *pCtx, 
  const void *z, 
  int n, 
  void (*xDel)(void *)
){
  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
  setResultStrOrError(pCtx, z, n, SQLITE_UTF16LE, xDel);
}
#endif /* SQLITE_OMIT_UTF16 */
void sqlite3_result_value(sqlite3_context *pCtx, sqlite3_value *pValue){
  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
  sqlite3VdbeMemCopy(&pCtx->s, pValue);
}
void sqlite3_result_zeroblob(sqlite3_context *pCtx, int n){

**
*************************************************************************
** This file contains code used for creating, destroying, and populating
** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.)  Prior
** to version 2.8.7, all this code was combined into the vdbe.c source file.
** But that file was getting too big so this subroutines were split out.
**
** $Id: vdbeaux.c,v 1.468 2009/07/06 00:44:09 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"



/*

  VdbeOp *pOp;

  i = p->nOp;
  assert( p->magic==VDBE_MAGIC_INIT );
  assert( op>0 && op<0xff );
  if( p->nOpAlloc<=i ){
    if( growOpArray(p) ){
      return 1;
    }
  }
  p->nOp++;
  pOp = &p->aOp[i];
  pOp->opcode = (u8)op;
  pOp->p5 = 0;
  pOp->p1 = p1;

int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp){
  int addr;
  assert( p->magic==VDBE_MAGIC_INIT );
  if( p->nOp + nOp > p->nOpAlloc && growOpArray(p) ){
    return 0;
  }
  addr = p->nOp;
  if( ALWAYS(nOp>0) ){
    int i;
    VdbeOpList const *pIn = aOp;
    for(i=0; i<nOp; i++, pIn++){
      int p2 = pIn->p2;
      VdbeOp *pOut = &p->aOp[i+addr];
      pOut->opcode = pIn->opcode;
      pOut->p1 = pIn->p1;

/*
** Change the value of the P1 operand for a specific instruction.
** This routine is useful when a large program is loaded from a
** static array using sqlite3VdbeAddOpList but we want to make a
** few minor changes to the program.
*/
void sqlite3VdbeChangeP1(Vdbe *p, int addr, int val){
  assert( p!=0 );
  assert( addr>=0 );
  if( p->nOp>addr ){
    p->aOp[addr].p1 = val;
  }
}

/*
** Change the value of the P2 operand for a specific instruction.
** This routine is useful for setting a jump destination.
*/
void sqlite3VdbeChangeP2(Vdbe *p, int addr, int val){
  assert( p!=0 );
  assert( addr>=0 );
  if( p->nOp>addr ){
    p->aOp[addr].p2 = val;
  }
}

/*
** Change the value of the P3 operand for a specific instruction.
*/
void sqlite3VdbeChangeP3(Vdbe *p, int addr, int val){
  assert( p!=0 );
  assert( addr>=0 );
  if( p->nOp>addr ){
    p->aOp[addr].p3 = val;
  }
}

/*
** Change the value of the P5 operand for the most recently
** added operation.
*/
void sqlite3VdbeChangeP5(Vdbe *p, u8 val){
  assert( p!=0 );
  if( p->aOp ){
    assert( p->nOp>0 );
    p->aOp[p->nOp-1].p5 = val;
  }
}

/*
** Change the P2 operand of instruction addr so that it points to
** the address of the next instruction to be coded.
*/
void sqlite3VdbeJumpHere(Vdbe *p, int addr){
  sqlite3VdbeChangeP2(p, addr, p->nOp);
}


/*
** If the input FuncDef structure is ephemeral, then free it.  If
** the FuncDef is not ephermal, then do nothing.
*/
static void freeEphemeralFunction(sqlite3 *db, FuncDef *pDef){
  if( ALWAYS(pDef) && (pDef->flags & SQLITE_FUNC_EPHEM)!=0 ){
    sqlite3DbFree(db, pDef);
  }
}

/*
** Delete a P4 value if necessary.
*/

}


/*
** Change N opcodes starting at addr to No-ops.
*/
void sqlite3VdbeChangeToNoop(Vdbe *p, int addr, int N){
  if( p->aOp ){
    VdbeOp *pOp = &p->aOp[addr];
    sqlite3 *db = p->db;
    while( N-- ){
      freeP4(db, pOp->p4type, pOp->p4.p);
      memset(pOp, 0, sizeof(pOp[0]));
      pOp->opcode = OP_Noop;
      pOp++;

  assert( p->magic==VDBE_MAGIC_INIT );
  if( p->aOp==0 || db->mallocFailed ){
    if (n != P4_KEYINFO) {
      freeP4(db, n, (void*)*(char**)&zP4);
    }
    return;
  }
  assert( p->nOp>0 );
  assert( addr<p->nOp );
  if( addr<0 ){
    addr = p->nOp - 1;

  }
  pOp = &p->aOp[addr];
  freeP4(db, pOp->p4type, pOp->p4.p);
  pOp->p4.p = 0;
  if( n==P4_INT32 ){
    /* Note: this cast is safe, because the origin data point was an int
    ** that was cast to a (const char *). */

){
  sqlite3 *db = p->db;
  int i;
  int rc = SQLITE_OK;
  Mem *pMem = p->pResultSet = &p->aMem[1];

  assert( p->explain );
  assert( p->magic==VDBE_MAGIC_RUN );
  assert( db->magic==SQLITE_MAGIC_BUSY );
  assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY || p->rc==SQLITE_NOMEM );

  /* Even though this opcode does not use dynamic strings for
  ** the result, result columns may become dynamic if the user calls
  ** sqlite3_column_text16(), causing a translation to UTF-16 encoding.
  */

  nMem += nCursor;

  /* Allocate space for memory registers, SQL variables, VDBE cursors and 
  ** an array to marshal SQL function arguments in. This is only done the
  ** first time this function is called for a given VDBE, not when it is
  ** being called from sqlite3_reset() to reset the virtual machine.
  */
  if( nVar>=0 && ALWAYS(db->mallocFailed==0) ){
    u8 *zCsr = (u8 *)&p->aOp[p->nOp];
    u8 *zEnd = (u8 *)&p->aOp[p->nOpAlloc];
    int nByte;
    int nArg;       /* Maximum number of args passed to a user function. */
    resolveP2Values(p, &nArg);
    if( isExplain && nMem<10 ){
      nMem = 10;

      if( nByte ){
        p->pFree = sqlite3DbMallocRaw(db, nByte);
      }
      zCsr = p->pFree;
      zEnd = &zCsr[nByte];
    }while( nByte && !db->mallocFailed );

    p->nCursor = (u16)nCursor;
    if( p->aVar ){
      p->nVar = (u16)nVar;
      for(n=0; n<nVar; n++){
        p->aVar[n].flags = MEM_Null;
        p->aVar[n].db = db;
      }
    }
    if( p->aMem ){
      p->aMem--;                      /* aMem[] goes from 1..nMem */

#endif
  if( !pCx->ephemPseudoTable ){
    sqlite3DbFree(p->db, pCx->pData);
  }
}

/*
** Close all cursors.

*/
static void closeAllCursors(Vdbe *p){
  int i;
  if( p->apCsr==0 ) return;
  for(i=0; i<p->nCursor; i++){
    VdbeCursor *pC = p->apCsr[i];
    if( pC ){
      sqlite3VdbeFreeCursor(p, pC);
      p->apCsr[i] = 0;
    }
  }
}

/*
** Clean up the VM after execution.
**
** This routine will automatically close any cursors, lists, and/or
** sorters that were left open.  It also deletes the values of
** variables in the aVar[] array.
*/
static void Cleanup(Vdbe *p){
  int i;
  sqlite3 *db = p->db;
  Mem *pMem;
  closeAllCursors(p);
  for(pMem=&p->aMem[1], i=1; i<=p->nMem; i++, pMem++){
    if( pMem->flags & MEM_RowSet ){
      sqlite3RowSetClear(pMem->u.pRowSet);
    }
    MemSetTypeFlag(pMem, MEM_Null);
  }
  releaseMemArray(&p->aMem[1], p->nMem);

  Mem *pColName;
  int n;
  sqlite3 *db = p->db;

  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
  sqlite3DbFree(db, p->aColName);
  n = nResColumn*COLNAME_N;
  p->nResColumn = (u16)nResColumn;
  p->aColName = pColName = (Mem*)sqlite3DbMallocZero(db, sizeof(Mem)*n );
  if( p->aColName==0 ) return;
  while( n-- > 0 ){
    pColName->flags = MEM_Null;
    pColName->db = p->db;
    pColName++;
  }

** takes care of the master journal trickery.
*/
static int vdbeCommit(sqlite3 *db, Vdbe *p){
  int i;
  int nTrans = 0;  /* Number of databases with an active write-transaction */
  int rc = SQLITE_OK;
  int needXcommit = 0;

#ifdef SQLITE_OMIT_VIRTUALTABLE
  /* With this option, sqlite3VtabSync() is defined to be simply 
  ** SQLITE_OK so p is not used. 
  */
  UNUSED_PARAMETER(p);
#endif

  /* Before doing anything else, call the xSync() callback for any
  ** virtual module tables written in this transaction. This has to
  ** be done before determining whether a master journal file is 
  ** required, as an xSync() callback may add an attached database
  ** to the transaction.
  */

  ** state.  We need to rollback the statement transaction, if there is
  ** one, or the complete transaction if there is no statement transaction.
  */

  if( p->db->mallocFailed ){
    p->rc = SQLITE_NOMEM;
  }
  closeAllCursors(p);
  if( p->magic!=VDBE_MAGIC_RUN ){
    return SQLITE_OK;
  }
  checkActiveVdbeCnt(db);

  /* No commit or rollback needed if the program never started */
  if( p->pc>=0 ){

  }
  assert( u<=pKeyInfo->nField + 1 );
  p->nField = u;
  return (void*)p;
}

/*
** This routine destroys a UnpackedRecord object.
*/
void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord *p){


  int i;
  Mem *pMem;

  assert( p!=0 );
  assert( p->flags & UNPACKED_NEED_DESTROY );
  for(i=0, pMem=p->aMem; i<p->nField; i++, pMem++){
    if( pMem->zMalloc ){
      sqlite3VdbeMemRelease(pMem);
    }
  }

  if( p->flags & UNPACKED_NEED_FREE ){
    sqlite3DbFree(p->pKeyInfo->db, p);

  }
}

/*
** This function compares the two table rows or index records
** specified by {nKey1, pKey1} and pPKey2.  It returns a negative, zero
** or positive integer if key1 is less than, equal to or 

  int rc;
  u32 szHdr;        /* Size of the header */
  u32 typeRowid;    /* Serial type of the rowid */
  u32 lenRowid;     /* Size of the rowid */
  Mem m, v;

  /* Get the size of the index entry.  Only indices entries of less
  ** than 2GiB are support - anything large must be database corruption.
  ** Any corruption is detected in sqlite3BtreeParseCellPtr(), though, so
  ** this code can safely assume that nCellKey is 32-bits  */
  sqlite3BtreeKeySize(pCur, &nCellKey);

  assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey );


  /* Read in the complete content of the index entry */
  m.flags = 0;
  m.db = db;
  m.zMalloc = 0;
  rc = sqlite3VdbeMemFromBtree(pCur, 0, (int)nCellKey, 1, &m);
  if( rc ){
    return rc;
  }

  /* The index entry must begin with a header size */
  (void)getVarint32((u8*)m.z, szHdr);
  testcase( szHdr==3 );
  testcase( szHdr==m.n );
  if( unlikely(szHdr<3 || (int)szHdr>m.n) ){
    goto idx_rowid_corruption;
  }

  /* The last field of the index should be an integer - the ROWID.
  ** Verify that the last entry really is an integer. */
  (void)getVarint32((u8*)&m.z[szHdr-1], typeRowid);
  testcase( typeRowid==1 );
  testcase( typeRowid==2 );
  testcase( typeRowid==3 );
  testcase( typeRowid==4 );
  testcase( typeRowid==5 );
  testcase( typeRowid==6 );
  testcase( typeRowid==8 );
  testcase( typeRowid==9 );
  if( unlikely(typeRowid<1 || typeRowid>9 || typeRowid==7) ){
    goto idx_rowid_corruption;
  }
  lenRowid = sqlite3VdbeSerialTypeLen(typeRowid);
  testcase( m.n==szHdr+lenRowid );
  if( unlikely(m.n<szHdr+lenRowid) ){
    goto idx_rowid_corruption;
  }

  /* Fetch the integer off the end of the index record */
  sqlite3VdbeSerialGet((u8*)&m.z[m.n-lenRowid], typeRowid, &v);
  *rowid = v.u.i;
  sqlite3VdbeMemRelease(&m);
  return SQLITE_OK;

  /* Jump here if database corruption is detected after m has been
  ** allocated.  Free the m object and return SQLITE_CORRUPT. */
idx_rowid_corruption:
  testcase( m.zMalloc!=0 );
  sqlite3VdbeMemRelease(&m);
  return SQLITE_CORRUPT_BKPT;
}

/*
** Compare the key of the index entry that cursor pC is pointing to against
** the key string in pUnpacked.  Write into *pRes a number
** that is negative, zero, or positive if pC is less than, equal to,
** or greater than pUnpacked.  Return SQLITE_OK on success.
**
** pUnpacked is either created without a rowid or is truncated so that it
** omits the rowid at the end.  The rowid at the end of the index entry
** is ignored as well.  Hence, this routine only compares the prefixes 
** of the keys prior to the final rowid, not the entire key.



*/
int sqlite3VdbeIdxKeyCompare(
  VdbeCursor *pC,             /* The cursor to compare against */
  UnpackedRecord *pUnpacked,  /* Unpacked version of key to compare against */
  int *res                    /* Write the comparison result here */
){
  i64 nCellKey = 0;
  int rc;
  BtCursor *pCur = pC->pCursor;
  Mem m;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement incremental BLOB I/O.
**
** $Id: vdbeblob.c,v 1.35 2009/07/02 07:47:33 danielk1977 Exp $
*/

#include "sqliteInt.h"
#include "vdbeInt.h"

#ifndef SQLITE_OMIT_INCRBLOB

  ** The sqlite3_blob_close() function finalizes the vdbe program,
  ** which closes the b-tree cursor and (possibly) commits the 
  ** transaction.
  */
  static const VdbeOpList openBlob[] = {
    {OP_Transaction, 0, 0, 0},     /* 0: Start a transaction */
    {OP_VerifyCookie, 0, 0, 0},    /* 1: Check the schema cookie */
    {OP_TableLock, 0, 0, 0},       /* 2: Acquire a read or write lock */

    /* One of the following two instructions is replaced by an OP_Noop. */


    {OP_OpenRead, 0, 0, 0},        /* 3: Open cursor 0 for reading */
    {OP_OpenWrite, 0, 0, 0},       /* 4: Open cursor 0 for read/write */

    {OP_Variable, 1, 1, 1},        /* 5: Push the rowid to the stack */
    {OP_NotExists, 0, 9, 1},       /* 6: Seek the cursor */
    {OP_Column, 0, 0, 1},          /* 7  */
    {OP_ResultRow, 1, 0, 0},       /* 8  */
    {OP_Close, 0, 0, 0},           /* 9  */
    {OP_Halt, 0, 0, 0},            /* 10 */
  };

  Vdbe *v = 0;
  int rc = SQLITE_OK;
  char *zErr = 0;
  Table *pTab;
  Parse *pParse;

      }
    }

    v = sqlite3VdbeCreate(db);
    if( v ){
      int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
      sqlite3VdbeAddOpList(v, sizeof(openBlob)/sizeof(VdbeOpList), openBlob);
      flags = !!flags;                 /* flags = (flags ? 1 : 0); */

      /* Configure the OP_Transaction */
      sqlite3VdbeChangeP1(v, 0, iDb);
      sqlite3VdbeChangeP2(v, 0, flags);

      /* Configure the OP_VerifyCookie */
      sqlite3VdbeChangeP1(v, 1, iDb);
      sqlite3VdbeChangeP2(v, 1, pTab->pSchema->schema_cookie);

      /* Make sure a mutex is held on the table to be accessed */
      sqlite3VdbeUsesBtree(v, iDb); 

      /* Configure the OP_TableLock instruction */
      sqlite3VdbeChangeP1(v, 2, iDb);
      sqlite3VdbeChangeP2(v, 2, pTab->tnum);
      sqlite3VdbeChangeP3(v, 2, flags);
      sqlite3VdbeChangeP4(v, 2, pTab->zName, P4_TRANSIENT);

      /* Remove either the OP_OpenWrite or OpenRead. Set the P2 
      ** parameter of the other to pTab->tnum.  */


      sqlite3VdbeChangeToNoop(v, 4 - flags, 1);
      sqlite3VdbeChangeP2(v, 3 + flags, pTab->tnum);
      sqlite3VdbeChangeP3(v, 3 + flags, iDb);

      /* Configure the number of columns. Configure the cursor to
      ** think that the table has one more column than it really
      ** does. An OP_Column to retrieve this imaginary column will
      ** always return an SQL NULL. This is useful because it means
      ** we can invoke OP_Column to fill in the vdbe cursors type 
      ** and offset cache without causing any IO.
      */
      sqlite3VdbeChangeP4(v, 3+flags, SQLITE_INT_TO_PTR(pTab->nCol+1),P4_INT32);
      sqlite3VdbeChangeP2(v, 7, pTab->nCol);
      if( !db->mallocFailed ){
        sqlite3VdbeMakeReady(v, 1, 1, 1, 0);
      }
    }
   
    sqlite3BtreeLeaveAll(db);
    rc = sqlite3SafetyOff(db);

*************************************************************************
**
** This file contains code use to manipulate "Mem" structure.  A "Mem"
** stores a single value in the VDBE.  Mem is an opaque structure visible
** only within the VDBE.  Interface routines refer to a Mem using the
** name sqlite_value
**
** $Id: vdbemem.c,v 1.150 2009/06/25 01:47:12 drh Exp $
*/
#include "sqliteInt.h"
#include "vdbeInt.h"

/*
** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
** P if required.

      preserve = 0;
    }else{
      sqlite3DbFree(pMem->db, pMem->zMalloc);
      pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n);
    }
  }

  if( pMem->z && preserve && pMem->zMalloc && pMem->z!=pMem->zMalloc ){
    memcpy(pMem->zMalloc, pMem->z, pMem->n);
  }
  if( pMem->flags&MEM_Dyn && pMem->xDel ){
    pMem->xDel((void *)(pMem->z));
  }

  pMem->z = pMem->zMalloc;

** result of the aggregate is stored back into pMem.
**
** Return SQLITE_ERROR if the finalizer reports an error.  SQLITE_OK
** otherwise.
*/
int sqlite3VdbeMemFinalize(Mem *pMem, FuncDef *pFunc){
  int rc = SQLITE_OK;
  if( ALWAYS(pFunc && pFunc->xFinalize) ){
    sqlite3_context ctx;
    assert( (pMem->flags & MEM_Null)!=0 || pFunc==pMem->u.pDef );
    assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
    memset(&ctx, 0, sizeof(ctx));
    ctx.s.flags = MEM_Null;
    ctx.s.db = pMem->db;
    ctx.pMem = pMem;
    ctx.pFunc = pFunc;
    pFunc->xFinalize(&ctx);
    assert( 0==(pMem->flags&MEM_Dyn) && !pMem->xDel );
    sqlite3DbFree(pMem->db, pMem->zMalloc);
    memcpy(pMem, &ctx.s, sizeof(ctx.s));
    rc = ctx.isError;
  }
  return rc;
}

/*
** If the memory cell contains a string value that must be freed by
** invoking an external callback, free it now. Calling this function

/*
** Delete any previous value and set the value of pMem to be an
** empty boolean index.
*/
void sqlite3VdbeMemSetRowSet(Mem *pMem){
  sqlite3 *db = pMem->db;
  assert( db!=0 );
  assert( (pMem->flags & MEM_RowSet)==0 );


  sqlite3VdbeMemRelease(pMem);
  pMem->zMalloc = sqlite3DbMallocRaw(db, 64);

  if( db->mallocFailed ){
    pMem->flags = MEM_Null;
  }else{
    assert( pMem->zMalloc );
    pMem->u.pRowSet = sqlite3RowSetInit(db, pMem->zMalloc, 
                                       sqlite3DbMallocSize(db, pMem->zMalloc));
    assert( pMem->u.pRowSet!=0 );