scummvm/engines/zvision/file/lzss_read_stream.h
2021-12-26 18:48:43 +01:00

71 lines
1.8 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 3 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, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef ZVISION_LZSS_STREAM_H
#define ZVISION_LZSS_STREAM_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 override;
uint32 read(void *dataPtr, uint32 dataSize) override;
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