XEEN: Implemented resource manager

1 files changed, 214 insertions, 0 deletions

diff --git a/engines/xeen/resources.cpp b/engines/xeen/resources.cpp
new file mode 100644
index 0000000000..f99be12c3d
--- /dev/null
+++ b/engines/xeen/resources.cpp
@@ -0,0 +1,214 @@
+/* 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.
+ *
+ */
+
+#include "common/scummsys.h"
+#include "common/archive.h"
+#include "common/memstream.h"
+#include "common/textconsole.h"
+#include "xeen/xeen.h"
+#include "xeen/resources.h"
+
+namespace Xeen {
+
+/**
+ * Xeen CC file implementation
+ */
+class CCArchive : public Common::Archive {
+private:
+	/**
+	 * Details of a single entry in a CC file index
+	 */
+	struct CCEntry {
+		uint16 _id;
+		uint32 _offset;
+		uint16 _size;
+
+		CCEntry() : _id(0), _offset(0), _size(0) {}
+		CCEntry(uint16 id, uint32 offset, uint32 size)
+			: _id(id), _offset(offset), _size(size) {
+		}
+	};
+
+	Common::Array<CCEntry> _index;
+	Common::String _filename;
+
+	uint16 convertNameToId(const Common::String &resourceName) const;
+
+	void loadIndex(Common::SeekableReadStream *stream);
+
+	bool getHeaderEntry(const Common::String &resourceName, CCEntry &ccEntry) const;
+public:
+	CCArchive(const Common::String &filename);
+	virtual ~CCArchive();
+
+	// Archive implementation
+	virtual bool hasFile(const Common::String &name) const;
+	virtual int listMembers(Common::ArchiveMemberList &list) const;
+	virtual const Common::ArchiveMemberPtr getMember(const Common::String &name) const;
+	virtual Common::SeekableReadStream *createReadStreamForMember(const Common::String &name) const;
+};
+
+CCArchive::CCArchive(const Common::String &filename): _filename(filename) {
+	File f(filename);
+	loadIndex(&f);
+}
+
+CCArchive::~CCArchive() {
+}
+
+// Archive implementation
+bool CCArchive::hasFile(const Common::String &name) const {
+	CCEntry ccEntry;
+	return getHeaderEntry(name, ccEntry);
+}
+
+int CCArchive::listMembers(Common::ArchiveMemberList &list) const {
+	// CC files don't maintain the original filenames, so we can't list it
+	return 0;
+}
+
+const Common::ArchiveMemberPtr CCArchive::getMember(const Common::String &name) const {
+	if (!hasFile(name))
+		return Common::ArchiveMemberPtr();
+
+	return Common::ArchiveMemberPtr(new Common::GenericArchiveMember(name, this));
+}
+
+Common::SeekableReadStream *CCArchive::createReadStreamForMember(const Common::String &name) const {
+	CCEntry ccEntry;
+
+	if (getHeaderEntry(name, ccEntry)) {
+		// Open the correct CC file
+		Common::File f;
+		if (!f.open(_filename))
+			error("Could not open CC file");
+
+		// Read in the data for the specific resource
+		f.seek(ccEntry._offset);
+		byte *data = new byte[ccEntry._size];
+		f.read(data, ccEntry._size);
+
+		// Decrypt the data
+		for (int i = 0; i < ccEntry._size; ++i)
+			data[i] ^= 0x35;
+
+		// Return the data as a stream
+		return new Common::MemoryReadStream(data, ccEntry._size, DisposeAfterUse::YES);
+	}
+
+	return nullptr;
+}
+
+/**
+ * Hash a given filename to produce the Id that represents it
+ */
+uint16 CCArchive::convertNameToId(const Common::String &resourceName) const {
+	if (resourceName.empty())
+		return 0xffff;
+
+	Common::String name = resourceName;
+	name.toUppercase();
+
+	const byte *msgP = (const byte *)name.c_str();
+	int total = *msgP++;
+	for (; *msgP; total += *msgP++) {
+		// Rotate the bits in 'total' right 7 places
+		total = (total & 0x007F) << 9 | (total & 0xFF80) >> 7;
+	}
+
+	return total;
+}
+
+/**
+ * Load the index of a given CC file
+ */
+void CCArchive::loadIndex(Common::SeekableReadStream *stream) {
+	int count = stream->readUint16LE();
+
+	// Read in the data for the archive's index
+	byte *rawIndex = new byte[count * 8];
+	stream->read(rawIndex, count * 8);
+
+	// Decrypt the index
+	int ah = 0xac;
+	for (int i = 0; i < count * 8; ++i) {
+		rawIndex[i] = (byte)(((rawIndex[i] << 2 | rawIndex[i] >> 6) + ah) & 0xff);
+		ah += 0x67;
+	}
+
+	// Extract the index data into entry structures
+	_index.reserve(count);
+	const byte *entryP = &rawIndex[0];
+	for (int i = 0; i < count; ++i, entryP += 8) {
+		CCEntry entry;
+		entry._id = READ_LE_UINT16(entryP);
+		entry._offset = READ_LE_UINT32(entryP + 2) & 0xffffff;
+		entry._size = READ_LE_UINT16(entryP + 5);
+		assert(!entryP[7]);
+
+		_index.push_back(entry);
+	}
+
+	delete[] rawIndex;
+}
+
+/**
+* Given a resource name, returns whether an entry exists, and returns
+* the header index data for that entry
+*/
+bool CCArchive::getHeaderEntry(const Common::String &resourceName, CCEntry &ccEntry) const {
+	uint16 id = convertNameToId(resourceName);
+
+	// Loop through the index
+	for (uint i = 0; i < _index.size(); ++i) {
+		if (_index[i]._id == id) {
+			ccEntry = _index[i];
+			return true;
+		}
+	}
+
+	// Could not find an entry
+	return false;
+}
+
+/*------------------------------------------------------------------------*/
+
+void Resources::init(XeenEngine *vm) {
+	Common::File f;
+
+	const char *ARCHIVES[3] = { "xeen", "dark", "intro" };
+	for (int i = 0; i < 3; ++i) {
+		Common::String filename = Common::String::format("%s.cc", ARCHIVES[i]);
+		if (f.exists(filename)) {
+			SearchMan.add(ARCHIVES[i], new CCArchive(filename));
+		}
+	}
+}
+
+/*------------------------------------------------------------------------*/
+
+void File::openFile(const Common::String &filename) {
+	if (!Common::File::open(filename))
+		error("Could not open file - %s", filename.c_str());
+}
+
+} // End of namespace Xeen