/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/


// MARKER(update_precomp.py): autogen include statement, do not remove
#include "precompiled_tools.hxx"

#define _VCOMPAT_CXX
#include <tools/stream.hxx>
#include <tools/vcompat.hxx>

// -----------------
// - VersionCompat -
// -----------------

VersionCompat::VersionCompat( SvStream& rStm, sal_uInt16 nStreamMode, sal_uInt16 nVersion ) :
            mpRWStm     ( &rStm ),
            mnStmMode   ( nStreamMode ),
            mnVersion   ( nVersion )
{
    if( !mpRWStm->GetError() )
    {
        if( STREAM_WRITE == mnStmMode )
        {
            *mpRWStm << mnVersion;
            mnTotalSize = ( mnCompatPos = mpRWStm->Tell() ) + 4UL;
            mpRWStm->SeekRel( 4L );
        }
        else
        {
            *mpRWStm >> mnVersion;
            *mpRWStm >> mnTotalSize;
            mnCompatPos = mpRWStm->Tell();
        }
    }
}

// ------------------------------------------------------------------------

VersionCompat::~VersionCompat()
{
    if( STREAM_WRITE == mnStmMode )
    {
        const sal_uInt32 nEndPos = mpRWStm->Tell();

        mpRWStm->Seek( mnCompatPos );
        *mpRWStm << ( nEndPos - mnTotalSize );
        mpRWStm->Seek( nEndPos );
    }
    else
    {
        const sal_uInt32 nReadSize = mpRWStm->Tell() - mnCompatPos;

        if( mnTotalSize > nReadSize )
            mpRWStm->SeekRel( mnTotalSize - nReadSize );
    }
}