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diff --git a/common/substream.h b/common/substream.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.
+ *
+ * $URL$
+ * $Id$
+ *
+ */
+
+#ifndef COMMON_SUBSTREAM_H
+#define COMMON_SUBSTREAM_H
+
+#include "common/stream.h"
+
+namespace Common {
+
+/**
+ * SubReadStream provides access to a ReadStream restricted to the range
+ * [currentPosition, currentPosition+end).
+ *
+ * Manipulating the parent stream directly /will/ mess up a substream.
+ * Likewise, manipulating two substreams of a parent stream will cause them to
+ * step on each others toes.
+ */
+class SubReadStream : virtual public ReadStream {
+protected:
+	ReadStream *_parentStream;
+	DisposeAfterUse::Flag _disposeParentStream;
+	uint32 _pos;
+	uint32 _end;
+	bool _eos;
+public:
+	SubReadStream(ReadStream *parentStream, uint32 end, DisposeAfterUse::Flag disposeParentStream = DisposeAfterUse::NO)
+		: _parentStream(parentStream),
+		  _disposeParentStream(disposeParentStream),
+		  _pos(0),
+		  _end(end),
+		  _eos(false) {
+		assert(parentStream);
+	}
+	~SubReadStream() {
+		if (_disposeParentStream)
+			delete _parentStream;
+	}
+
+	virtual bool eos() const { return _eos; }
+	virtual bool err() const { return _parentStream->err(); }
+	virtual void clearErr() { _eos = false; _parentStream->clearErr(); }
+	virtual uint32 read(void *dataPtr, uint32 dataSize);
+};
+
+/*
+ * SeekableSubReadStream provides access to a SeekableReadStream restricted to
+ * the range [begin, end).
+ * The same caveats apply to SeekableSubReadStream as do to SeekableReadStream.
+ *
+ * Manipulating the parent stream directly /will/ mess up a substream.
+ * @see SubReadStream
+ */
+class SeekableSubReadStream : public SubReadStream, public SeekableReadStream {
+protected:
+	SeekableReadStream *_parentStream;
+	uint32 _begin;
+public:
+	SeekableSubReadStream(SeekableReadStream *parentStream, uint32 begin, uint32 end, DisposeAfterUse::Flag disposeParentStream = DisposeAfterUse::NO);
+
+	virtual int32 pos() const { return _pos - _begin; }
+	virtual int32 size() const { return _end - _begin; }
+
+	virtual bool seek(int32 offset, int whence = SEEK_SET);
+};
+
+/**
+ * This is a wrapper around SeekableSubReadStream, but it adds non-endian
+ * read methods whose endianness is set on the stream creation.
+ *
+ * Manipulating the parent stream directly /will/ mess up a substream.
+ * @see SubReadStream
+ */
+class SeekableSubReadStreamEndian : public SeekableSubReadStream {
+private:
+	const bool _bigEndian;
+
+public:
+	SeekableSubReadStreamEndian(SeekableReadStream *parentStream, uint32 begin, uint32 end, bool bigEndian = false, DisposeAfterUse::Flag disposeParentStream = DisposeAfterUse::NO)
+		: SeekableSubReadStream(parentStream, begin, end, disposeParentStream), _bigEndian(bigEndian) {
+	}
+
+	uint16 readUint16() {
+		uint16 val;
+		read(&val, 2);
+		return (_bigEndian) ? TO_BE_16(val) : TO_LE_16(val);
+	}
+
+	uint32 readUint32() {
+		uint32 val;
+		read(&val, 4);
+		return (_bigEndian) ? TO_BE_32(val) : TO_LE_32(val);
+	}
+
+	FORCEINLINE int16 readSint16() {
+		return (int16)readUint16();
+	}
+
+	FORCEINLINE int32 readSint32() {
+		return (int32)readUint32();
+	}
+};
+
+
+}	// End of namespace Common
+
+#endif