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diff --git a/engines/zvision/lzss_read_stream.h b/engines/zvision/lzss_read_stream.h
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+++ b/engines/zvision/lzss_read_stream.h
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+/* 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/memstream.h"
+#include "common/array.h"
+
+namespace ZVision {
+
+class LzssReadStream : public Common::ReadStream {
+public:
+	/**
+	 * A class that decompresses LZSS data and implements ReadStream for easy access 
+	 * to the decompiled data. It can either decompress all the data in the beginning 
+	 * or decompress as needed by read().
+	 *
+	 * @param source              The source data
+	 * @param stream			  Decompress the data as needed (true) or all at once (false)
+	 * @param decompressedSize    The size of the decompressed data. If npos, the class will choose a size and grow as needed
+	 */
+	LzssReadStream(Common::SeekableReadStream *source, bool stream = true, uint32 decompressedSize = npos);
+
+public:
+	static const uint32 npos = 0xFFFFFFFFu;
+	static const uint16 blockSize = 0x1000u;
+
+private:
+	Common::SeekableReadStream *_source;
+	Common::Array<char> _destination;
+	char _window[blockSize];
+	uint16 _windowCursor;
+	uint32 _readCursor;
+
+public:
+	bool eos() const;
+	uint32 read(void *dataPtr, uint32 dataSize);
+	uint32 currentSize() const;
+
+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
+	 */
+	void decompressBytes(uint32 numberOfBytes);
+	/** Decompress all of the source stream. */
+	void decompressAll();
+};
+
+}
+
+#endif