svx/source/gallery2/codec.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20
  21 #include <tools/stream.hxx>
  22 #include <tools/zcodec.hxx>
  23 #include <tools/debug.hxx>
  24 #include "codec.hxx"
  25
  26 // ----------------
  27 // - GalleryCodec -
  28 // ----------------
  29 DBG_NAME(GalleryCodec)
  30
  31 GalleryCodec::GalleryCodec( SvStream& rIOStm ) :
  32     rStm( rIOStm )
  33 {
  34     DBG_CTOR(GalleryCodec,NULL);
  35 }
  36
  37 // -----------------------------------------------------------------------------
  38
  39 GalleryCodec::~GalleryCodec()
  40 {
  41     DBG_DTOR(GalleryCodec,NULL);
  42 }
  43
  44 // -----------------------------------------------------------------------------
  45
  46 sal_Bool GalleryCodec::IsCoded( SvStream& rStm, sal_uInt32& rVersion )
  47 {
  48     const sal_uIntPtr   nPos = rStm.Tell();
  49     sal_Bool        bRet;
  50     sal_uInt8       cByte1, cByte2, cByte3, cByte4, cByte5, cByte6;
  51
  52     rStm >> cByte1 >> cByte2 >> cByte3 >> cByte4 >> cByte5 >> cByte6;
  53
  54     if ( cByte1 == 'S' && cByte2 == 'V' && cByte3 == 'R' && cByte4 == 'L' && cByte5 == 'E' && ( cByte6 == '1' || cByte6 == '2' ) )
  55     {
  56         rVersion = ( ( cByte6 == '1' ) ? 1 : 2 );
  57         bRet = sal_True;
  58     }
  59     else
  60     {
  61         rVersion = 0;
  62         bRet = sal_False;
  63     }
  64
  65     rStm.Seek( nPos );
  66
  67     return bRet;
  68 }
  69
  70 // -----------------------------------------------------------------------------
  71
  72 void GalleryCodec::Write( SvStream& rStmToWrite )
  73 {
  74     sal_uInt32 nPos, nCompSize;
  75
  76     rStmToWrite.Seek( STREAM_SEEK_TO_END );
  77     const sal_uInt32 nSize = rStmToWrite.Tell();
  78     rStmToWrite.Seek( 0UL );
  79
  80     rStm << 'S' << 'V' << 'R' << 'L' << 'E' << '2';
  81     rStm << nSize;
  82
  83     nPos = rStm.Tell();
  84     rStm.SeekRel( 4UL );
  85
  86     ZCodec aCodec;
  87     aCodec.BeginCompression();
  88     aCodec.Compress( rStmToWrite, rStm );
  89     aCodec.EndCompression();
  90
  91     nCompSize = rStm.Tell() - nPos - 4UL;
  92     rStm.Seek( nPos );
  93     rStm << nCompSize;
  94     rStm.Seek( STREAM_SEEK_TO_END );
  95 }
  96
  97 // -----------------------------------------------------------------------------
  98
  99 void GalleryCodec::Read( SvStream& rStmToRead )
 100 {
 101     sal_uInt32 nVersion = 0;
 102
 103     if( IsCoded( rStm, nVersion ) )
 104     {
 105         sal_uInt32  nCompressedSize, nUnCompressedSize;
 106
 107         rStm.SeekRel( 6 );
 108         rStm >> nUnCompressedSize >> nCompressedSize;
 109
 110         // decompress
 111         if( 1 == nVersion )
 112         {
 113             sal_uInt8*   pCompressedBuffer = new sal_uInt8[ nCompressedSize ]; rStm.Read( pCompressedBuffer, nCompressedSize );
 114             sal_uInt8*  pInBuf = pCompressedBuffer;
 115             sal_uInt8*  pOutBuf = new sal_uInt8[ nUnCompressedSize ];
 116             sal_uInt8*  pTmpBuf = pOutBuf;
 117             sal_uInt8*  pLast = pOutBuf + nUnCompressedSize - 1;
 118             sal_uIntPtr   nIndex = 0UL, nCountByte, nRunByte;
 119             sal_Bool    bEndDecoding = sal_False;
 120
 121             do
 122             {
 123                 nCountByte = *pInBuf++;
 124
 125                 if ( !nCountByte )
 126                 {
 127                     nRunByte = *pInBuf++;
 128
 129                     if ( nRunByte > 2 )
 130                     {
 131                         // absolutes Fuellen
 132                         memcpy( &pTmpBuf[ nIndex ], pInBuf, nRunByte );
 133                         pInBuf += nRunByte;
 134                         nIndex += nRunByte;
 135
 136                         // WORD-Alignment beachten
 137                         if ( nRunByte & 1 )
 138                             pInBuf++;
 139                     }
 140                     else if ( nRunByte == 1 )   // Ende des Bildes
 141                         bEndDecoding = sal_True;
 142                 }
 143                 else
 144                 {
 145                     const sal_uInt8 cVal = *pInBuf++;
 146
 147                     memset( &pTmpBuf[ nIndex ], cVal, nCountByte );
 148                     nIndex += nCountByte;
 149                 }
 150             }
 151             while ( !bEndDecoding && ( pTmpBuf <= pLast ) );
 152
 153                rStmToRead.Write( pOutBuf, nUnCompressedSize );
 154
 155             delete[] pOutBuf;
 156             delete[] pCompressedBuffer;
 157         }
 158         else if( 2 == nVersion )
 159         {
 160             ZCodec aCodec;
 161
 162             aCodec.BeginCompression();
 163             aCodec.Decompress( rStm, rStmToRead );
 164             aCodec.EndCompression();
 165         }
 166     }
 167 }
 168
 169 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */