Initial commit

engines/zvision/file/zfs_archive.cpp

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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 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/>.
+ *
+ */
+
+#include "common/debug.h"
+#include "common/file.h"
+#include "common/memstream.h"
+#include "common/scummsys.h"
+#include "zvision/detection.h"
+#include "zvision/file/zfs_archive.h"
+
+namespace ZVision {
+
+ZfsArchive::ZfsArchive(const Common::Path &fileName) : _fileName(fileName) {
+	Common::File zfsFile;
+	memset(&_header, 0, sizeof(_header));
+
+	if (!zfsFile.open(_fileName)) {
+		warning("ZFSArchive::ZFSArchive(): Could not find the archive file");
+		return;
+	}
+
+	readHeaders(&zfsFile);
+
+	debugC(1, kDebugFile, "ZfsArchive::ZfsArchive(%s): Located %d files", _fileName.toString(Common::Path::kNativeSeparator).c_str(), _entryHeaders.size());
+}
+
+ZfsArchive::ZfsArchive(const Common::Path &fileName, Common::SeekableReadStream *stream) : _fileName(fileName) {
+	readHeaders(stream);
+
+	debugC(1, kDebugFile, "ZfsArchive::ZfsArchive(%s): Located %d files", _fileName.toString(Common::Path::kNativeSeparator).c_str(), _entryHeaders.size());
+}
+
+ZfsArchive::~ZfsArchive() {
+	debugC(1, kDebugFile, "ZfsArchive Destructor Called");
+	ZfsEntryHeaderMap::iterator it = _entryHeaders.begin();
+	for (; it != _entryHeaders.end(); ++it) {
+		delete it->_value;
+	}
+}
+
+void ZfsArchive::readHeaders(Common::SeekableReadStream *stream) {
+	// Don't do a straight struct cast since we can't guarantee endianness
+	_header.magic = stream->readUint32LE();
+	_header.unknown1 = stream->readUint32LE();
+	_header.maxNameLength = stream->readUint32LE();
+	_header.filesPerBlock = stream->readUint32LE();
+	_header.fileCount = stream->readUint32LE();
+	_header.xorKey[0] = stream->readByte();
+	_header.xorKey[1] = stream->readByte();
+	_header.xorKey[2] = stream->readByte();
+	_header.xorKey[3] = stream->readByte();
+	_header.fileSectionOffset = stream->readUint32LE();
+
+	uint32 nextOffset;
+
+	do {
+		// Read the offset to the next block
+		nextOffset = stream->readUint32LE();
+
+		// Read in each entry header
+		for (uint32 i = 0; i < _header.filesPerBlock; ++i) {
+			ZfsEntryHeader entryHeader;
+
+			entryHeader.name = readEntryName(stream);
+			entryHeader.offset = stream->readUint32LE();
+			entryHeader.id = stream->readUint32LE();
+			entryHeader.size = stream->readUint32LE();
+			entryHeader.time = stream->readUint32LE();
+			entryHeader.unknown = stream->readUint32LE();
+
+			if (entryHeader.size != 0)
+				_entryHeaders[entryHeader.name] = new ZfsEntryHeader(entryHeader);
+		}
+
+		// Seek to the next block of headers
+		stream->seek(nextOffset);
+	} while (nextOffset != 0);
+}
+
+Common::String ZfsArchive::readEntryName(Common::SeekableReadStream *stream) const {
+	// Entry Names are at most 16 bytes and are null padded
+	char buffer[16];
+	stream->read(buffer, 16);
+
+	return Common::String(buffer);
+}
+
+bool ZfsArchive::hasFile(const Common::Path &path) const {
+	Common::String name = path.toString();
+	return _entryHeaders.contains(name);
+}
+
+int ZfsArchive::listMembers(Common::ArchiveMemberList &list) const {
+	int matches = 0;
+
+	for (ZfsEntryHeaderMap::const_iterator it = _entryHeaders.begin(); it != _entryHeaders.end(); ++it) {
+		list.push_back(Common::ArchiveMemberList::value_type(new Common::GenericArchiveMember(it->_value->name, *this)));
+		matches++;
+	}
+
+	return matches;
+}
+
+const Common::ArchiveMemberPtr ZfsArchive::getMember(const Common::Path &path) const {
+	if (!hasFile(path))
+		return Common::ArchiveMemberPtr();
+
+	return Common::ArchiveMemberPtr(new Common::GenericArchiveMember(path, *this));
+}
+
+Common::SeekableReadStream *ZfsArchive::createReadStreamForMember(const Common::Path &path) const {
+	Common::String name = path.toString();
+	if (!_entryHeaders.contains(name)) {
+		return 0;
+	}
+
+	ZfsEntryHeader *entryHeader = _entryHeaders[name];
+
+	Common::File zfsArchive;
+	zfsArchive.open(_fileName);
+	zfsArchive.seek(entryHeader->offset);
+
+	// This *HAS* to be malloc (not new[]) because MemoryReadStream uses free() to free the memory
+	byte *buffer = (byte *)malloc(entryHeader->size);
+	zfsArchive.read(buffer, entryHeader->size);
+	// Decrypt the data in place
+	if (_header.xorKey[0] + _header.xorKey[1] + _header.xorKey[2] + _header.xorKey[3] != 0)
+		unXor(buffer, entryHeader->size, _header.xorKey);
+
+	return new Common::MemoryReadStream(buffer, entryHeader->size, DisposeAfterUse::YES);
+}
+
+void ZfsArchive::unXor(byte *buffer, uint32 length, const byte *xorKey) const {
+	for (uint32 i = 0; i < length; ++i)
+		buffer[i] ^= xorKey[i % 4];
+}
+
+} // End of namespace ZVision