AOO410/main/svx/source/gallery2/codec.cxx

/**************************************************************
 * 
 * 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_svx.hxx"

#include <tools/stream.hxx>
#include <tools/zcodec.hxx>
#include "codec.hxx"
#include <tools/debug.hxx>

// ----------------
// - GalleryCodec -
// ----------------
DBG_NAME(GalleryCodec)

GalleryCodec::GalleryCodec( SvStream& rIOStm ) : 
    rStm( rIOStm )
{
    DBG_CTOR(GalleryCodec,NULL);

}

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

GalleryCodec::~GalleryCodec()
{

    DBG_DTOR(GalleryCodec,NULL);
}

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

sal_Bool GalleryCodec::IsCoded( SvStream& rStm, sal_uInt32& rVersion )
{
	const sal_uIntPtr	nPos = rStm.Tell();
	sal_Bool		bRet;
	sal_uInt8		cByte1, cByte2, cByte3, cByte4, cByte5, cByte6;

	rStm >> cByte1 >> cByte2 >> cByte3 >> cByte4 >> cByte5 >> cByte6;

	if ( cByte1 == 'S' && cByte2 == 'V' && cByte3 == 'R' && cByte4 == 'L' && cByte5 == 'E' && ( cByte6 == '1' || cByte6 == '2' ) )
	{
        rVersion = ( ( cByte6 == '1' ) ? 1 : 2 );
		bRet = sal_True;
	}
    else
    {
        rVersion = 0;
		bRet = sal_False;
    }

	rStm.Seek( nPos );

	return bRet;
}

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

void GalleryCodec::Write( SvStream& rStmToWrite )
{
	sal_uInt32 nPos, nCompSize;
	
    rStmToWrite.Seek( STREAM_SEEK_TO_END );
	const sal_uInt32 nSize = rStmToWrite.Tell();
	rStmToWrite.Seek( 0UL );

	rStm << 'S' << 'V' << 'R' << 'L' << 'E' << '2';
	rStm << nSize;

	nPos = rStm.Tell();
	rStm.SeekRel( 4UL );

    ZCodec aCodec;
    aCodec.BeginCompression();
    aCodec.Compress( rStmToWrite, rStm );
    aCodec.EndCompression();

	nCompSize = rStm.Tell() - nPos - 4UL;
	rStm.Seek( nPos );
	rStm << nCompSize;
	rStm.Seek( STREAM_SEEK_TO_END );
}

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

void GalleryCodec::Read( SvStream& rStmToRead )
{
	sal_uInt32 nVersion = 0;

	if( IsCoded( rStm, nVersion ) )
	{
		sal_uInt32	nCompressedSize, nUnCompressedSize;

		rStm.SeekRel( 6 );
		rStm >> nUnCompressedSize >> nCompressedSize;

		// decompress
        if( 1 == nVersion )
        {
            sal_uInt8*   pCompressedBuffer = new sal_uInt8[ nCompressedSize ]; rStm.Read( pCompressedBuffer, nCompressedSize );
	        sal_uInt8*	pInBuf = pCompressedBuffer;
	        sal_uInt8*	pOutBuf = new sal_uInt8[ nUnCompressedSize ];
	        sal_uInt8*	pTmpBuf = pOutBuf;
	        sal_uInt8*	pLast = pOutBuf + nUnCompressedSize - 1;
	        sal_uIntPtr   nIndex = 0UL, nCountByte, nRunByte;
	        sal_Bool    bEndDecoding = sal_False;

	        do
	        {
		        nCountByte = *pInBuf++;

		        if ( !nCountByte )
		        {
			        nRunByte = *pInBuf++;

			        if ( nRunByte > 2 )
			        {
				        // absolutes Fuellen
				        memcpy( &pTmpBuf[ nIndex ], pInBuf, nRunByte );
				        pInBuf += nRunByte;
				        nIndex += nRunByte;

				        // WORD-Alignment beachten
				        if ( nRunByte & 1 )
					        pInBuf++;
			        }
			        else if ( nRunByte == 1 )   // Ende des Bildes
				        bEndDecoding = sal_True;
		        }
		        else
		        {
			        const sal_uInt8 cVal = *pInBuf++;

			        memset( &pTmpBuf[ nIndex ], cVal, nCountByte );
			        nIndex += nCountByte;
		        }
	        }
	        while ( !bEndDecoding && ( pTmpBuf <= pLast ) );

   		    rStmToRead.Write( pOutBuf, nUnCompressedSize );
            
            delete[] pOutBuf;
            delete[] pCompressedBuffer;
        }
        else if( 2 == nVersion )
        {
	        ZCodec aCodec;

            aCodec.BeginCompression();
            aCodec.Decompress( rStm, rStmToRead );
            aCodec.EndCompression();
        }
	}
}