AOO410/main/tools/source/stream/vcompat.cxx

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 * Licensed to the Apache Software Foundation (ASF) under one
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 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
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// 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 );
    }
}