Initial commit

engines/mohawk/installer_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 "mohawk/installer_archive.h"
+
+#include "common/compression/dcl.h"
+#include "common/debug.h"
+
+namespace Mohawk {
+
+InstallerArchive::InstallerArchive() : Common::Archive() {
+	_stream = nullptr;
+}
+
+InstallerArchive::~InstallerArchive() {
+	close();
+}
+
+bool InstallerArchive::open(const Common::Path &filename) {
+	close();
+
+	_stream = SearchMan.createReadStreamForMember(filename);
+
+	if (!_stream)
+		return false;
+
+	// Check for the magic uint32
+	// No idea what it means, but it's how "file" recognizes them
+	if (_stream->readUint32BE() != 0x135D658C) {
+		close();
+		return false;
+	}
+
+	// Let's pull some relevant data from the header
+	_stream->seek(41);
+	uint32 directoryTableOffset = _stream->readUint32LE();
+	/* uint32 directoryTableSize = */ _stream->readUint32LE();
+	uint16 directoryCount = _stream->readUint16LE();
+	uint32 fileTableOffset = _stream->readUint32LE();
+	/* uint32 fileTableSize = */ _stream->readUint32LE();
+
+	// We need to have at least one directory in order for the archive to be valid
+	if (directoryCount == 0) {
+		close();
+		return false;
+	}
+
+	// TODO: Currently, we only support getting files from the first directory
+	// To that end, get the number of files from that entry
+	_stream->seek(directoryTableOffset);
+	uint16 fileCount = _stream->readUint16LE();
+	debug(2, "File count = %d", fileCount);
+
+	// Following the directory table is the file table with files stored recursively
+	// by directory. Since we're only using the first directory, we can just go
+	// right to that one.
+	_stream->seek(fileTableOffset);
+
+	for (uint16 i = 0; i < fileCount; i++) {
+		FileEntry entry;
+
+		_stream->skip(3); // Unknown
+
+		entry.uncompressedSize = _stream->readUint32LE();
+		entry.compressedSize = _stream->readUint32LE();
+		entry.offset = _stream->readUint32LE();
+
+		_stream->skip(14); // Unknown
+
+		byte nameLength = _stream->readByte();
+		Common::String name;
+		while (nameLength--)
+			name += _stream->readByte();
+
+		_stream->skip(13); // Unknown
+
+		_map[Common::Path(name, '\\')] = entry;
+
+		debug(3, "Found file '%s' at 0x%08x (Comp: 0x%08x, Uncomp: 0x%08x)", name.c_str(),
+				entry.offset, entry.compressedSize, entry.uncompressedSize);
+	}
+
+	return true;
+}
+
+void InstallerArchive::close() {
+	delete _stream; _stream = nullptr;
+	_map.clear();
+}
+
+bool InstallerArchive::hasFile(const Common::Path &path) const {
+	return _map.contains(path);
+}
+
+int InstallerArchive::listMembers(Common::ArchiveMemberList &list) const {
+	for (FileMap::const_iterator it = _map.begin(); it != _map.end(); it++)
+		list.push_back(getMember(it->_key));
+
+	return _map.size();
+}
+
+const Common::ArchiveMemberPtr InstallerArchive::getMember(const Common::Path &path) const {
+	return Common::ArchiveMemberPtr(new Common::GenericArchiveMember(path, *this));
+}
+
+Common::SeekableReadStream *InstallerArchive::createReadStreamForMember(const Common::Path &path) const {
+	if (!_stream || !_map.contains(path))
+		return nullptr;
+
+	const FileEntry &entry = _map[path];
+
+	// Seek to our offset and then send it off to the decompressor
+	_stream->seek(entry.offset);
+	return Common::decompressDCL(_stream, entry.compressedSize, entry.uncompressedSize);
+}
+
+} // End of namespace Mohawk