scummvm/engines/mohawk/installer_archive.cpp
2011-03-22 19:54:59 -04:00

142 lines
4.0 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 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.
*
* $URL$
* $Id$
*
*/
#include "mohawk/installer_archive.h"
#include "common/dcl.h"
#include "common/debug.h"
#include "common/substream.h"
#include "common/util.h"
namespace Mohawk {
InstallerArchive::InstallerArchive() : Common::Archive() {
_stream = 0;
}
InstallerArchive::~InstallerArchive() {
close();
}
bool InstallerArchive::open(const Common::String &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[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 = 0;
_map.clear();
}
bool InstallerArchive::hasFile(const Common::String &name) {
return _map.contains(name);
}
int InstallerArchive::listMembers(Common::ArchiveMemberList &list) {
for (FileMap::const_iterator it = _map.begin(); it != _map.end(); it++)
list.push_back(getMember(it->_key));
return _map.size();
}
Common::ArchiveMemberPtr InstallerArchive::getMember(const Common::String &name) {
return Common::ArchiveMemberPtr(new Common::GenericArchiveMember(name, this));
}
Common::SeekableReadStream *InstallerArchive::createReadStreamForMember(const Common::String &name) const {
if (!_stream || !_map.contains(name))
return 0;
const FileEntry &entry = _map[name];
// 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