scummvm/engines/zvision/lzss_read_stream.h

73 lines
1.9 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#ifndef ZVISION_LZSS_STREAM_H
#define ZVISION_LZSS_STREAM_H
#include "common/types.h"
#include "common/stream.h"
#include "common/array.h"
namespace Common {
class SeekableReadStream;
}
namespace ZVision {
class LzssReadStream : public Common::ReadStream {
public:
/**
* A class that decompresses LZSS data and implements ReadStream for easy access
* to the decompiled data.
*
* @param source The source data
*/
LzssReadStream(Common::SeekableReadStream *source);
private:
enum {
BLOCK_SIZE = 0x1000
};
private:
Common::SeekableReadStream *_source;
byte _window[BLOCK_SIZE];
uint _windowCursor;
bool _eosFlag;
public:
bool eos() const;
uint32 read(void *dataPtr, uint32 dataSize);
private:
/**
* Decompress the next <numberOfBytes> from the source stream. Or until EOS
*
* @param numberOfBytes How many bytes to decompress. This is a count of source bytes, not destination bytes
*/
uint32 decompressBytes(byte* destination, uint32 numberOfBytes);
};
}
#endif