ObjFW  Diff

#import "OFTruncatedDataException.h"

#define LHSTREAM_BUFFER_SIZE 4096

@interface OFLHAArchive_LHStream: OFStream
{
@public
	OF_KINDOF(OFStream *) _stream;
	uint8_t _distanceBits, _dictionaryBits;
	unsigned char _buffer[LHSTREAM_BUFFER_SIZE];
	uint32_t _bytesConsumed;
	uint16_t _bufferIndex, _bufferLength;
	uint8_t _byte;
	uint8_t _bitIndex, _savedBitsLength;
	uint16_t _savedBits;
	unsigned char *_slidingWindow;
	uint32_t _slidingWindowIndex, _slidingWindowMask;
	int _state;
	uint16_t _symbolsLeft;
	struct of_huffman_tree *_codeLenTree, *_litLenTree, *_distTree;
	struct of_huffman_tree *_treeIter;
	uint16_t _codesCount, _codesReceived;
	bool _currentIsExtendedLength, _skip;
	uint8_t *_codesLengths;
	uint16_t _length;
	uint32_t _distance;
}

- (instancetype)of_initWithStream: (OF_KINDOF(OFStream *))stream
		     distanceBits: (uint8_t)distanceBits
		   dictionaryBits: (uint8_t)dictionaryBits;
@end

@interface OFLHAArchive_FileReadStream: OFStream <OFReadyForReadingObserving>
{
	OF_KINDOF(OFStream *) _stream;
	OF_KINDOF(OFStream *) _decompressedStream;
	OFLHAArchiveEntry *_entry;
	uint32_t _toRead, _bytesConsumed;
	uint16_t _CRC16;
	bool _atEndOfStream;
}

- (instancetype)of_initWithStream: (OF_KINDOF(OFStream *))stream
			    entry: (OFLHAArchiveEntry *)entry;
- (void)of_skip;
@end

enum state {
	STATE_BLOCK_HEADER,
	STATE_CODE_LEN_CODES_COUNT,

			if (stream->_bufferIndex < stream->_bufferLength)
				stream->_byte =
				    stream->_buffer[stream->_bufferIndex++];
			else {
				size_t length = [stream->_stream
				    readIntoBuffer: stream->_buffer
					    length: LHSTREAM_BUFFER_SIZE];

				stream->_bytesConsumed += (uint32_t)length;

				if OF_UNLIKELY (length < 1) {
					stream->_savedBits = ret;
					stream->_savedBitsLength = i;
					return false;
				}

	[_stream release];
	_stream = nil;
}
@end

@implementation OFLHAArchive_LHStream
- (instancetype)of_initWithStream: (OF_KINDOF(OFStream *))stream
		     distanceBits: (uint8_t)distanceBits
		   dictionaryBits: (uint8_t)dictionaryBits
{
	self = [super init];

	@try {
		_stream = [stream retain];

			 * We must also unread the buffer, in case this was the
			 * last block and something else follows, e.g. another
			 * LHA header.
			 */
			[_stream unreadFromBuffer: _buffer + _bufferIndex
					   length: _bufferLength -
						   _bufferIndex];
			_bytesConsumed -= _bufferLength - _bufferIndex;
			_bufferIndex = _bufferLength = 0;

			return bytesWritten;
		}

		if OF_UNLIKELY (length == 0)
			return bytesWritten;

{
	if (_stream == nil)
		@throw [OFNotOpenException exceptionWithObject: self];

	return ([_stream isAtEndOfStream] &&
	    _bufferLength - _bufferIndex == 0 && _state == STATE_BLOCK_HEADER);
}

- (int)fileDescriptorForReading
{
	return [_stream fileDescriptorForReading];
}

- (bool)hasDataInReadBuffer
{
	return ([super hasDataInReadBuffer] || [_stream hasDataInReadBuffer]);
}

- (void)close
{
	/* Give back our buffer to the stream, in case it's shared */
	[_stream unreadFromBuffer: _buffer + _bufferIndex
			   length: _bufferLength - _bufferIndex];
	_bytesConsumed -= _bufferLength - _bufferIndex;
	_bufferIndex = _bufferLength = 0;

	[_stream release];
	_stream = nil;

	[super close];
}
@end

@implementation OFLHAArchive_FileReadStream
- (instancetype)of_initWithStream: (OF_KINDOF(OFStream *))stream
			    entry: (OFLHAArchiveEntry *)entry
{
	self = [super init];

	@try {
		OFString *method;

		_stream = [stream retain];

		method = [entry method];

		if ([method isEqual: @"-lh4-"] || [method isEqual: @"-lh5-"])
			_decompressedStream = [[OFLHAArchive_LHStream alloc]
			    of_initWithStream: stream
				 distanceBits: 4
			       dictionaryBits: 14];
		else if ([method isEqual: @"-lh6-"])
			_decompressedStream = [[OFLHAArchive_LHStream alloc]
			    of_initWithStream: stream
				 distanceBits: 5
			       dictionaryBits: 16];
		else if ([method isEqual: @"-lh7-"])
			_decompressedStream = [[OFLHAArchive_LHStream alloc]
			    of_initWithStream: stream
				 distanceBits: 5
			       dictionaryBits: 17];
		else
			_decompressedStream = [stream retain];

		_entry = [entry copy];


		_toRead = [entry uncompressedSize];




	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	[self close];

	[_stream release];
	[_decompressedStream release];
	[_entry release];

	[super dealloc];
}

- (bool)lowlevelIsAtEndOfStream
{
	if (_stream == nil)
		@throw [OFNotOpenException exceptionWithObject: self];

	return _atEndOfStream;
}

- (size_t)lowlevelReadIntoBuffer: (void *)buffer
			  length: (size_t)length
{
	size_t ret;

	if (_stream == nil)
		@throw [OFNotOpenException exceptionWithObject: self];

	if (_atEndOfStream)
		return 0;

	if (length > _toRead)
		length = _toRead;

	ret = [_decompressedStream readIntoBuffer: buffer
					   length: length];

	_toRead -= ret;
	_CRC16 = of_crc16(_CRC16, buffer, ret);

	if (_toRead == 0) {
		_atEndOfStream = true;

		if (_CRC16 != [_entry CRC16])
			@throw [OFChecksumFailedException exception];
	}

	return ret;
}

- (bool)hasDataInReadBuffer
{
	return ([super hasDataInReadBuffer] ||
	    [_decompressedStream hasDataInReadBuffer]);
}

- (int)fileDescriptorForReading
{
	return [_decompressedStream fileDescriptorForReading];
}

- (void)of_skip
{
	OF_KINDOF(OFStream *) stream;
	uint32_t toRead;

	if (_stream == nil || _toRead == 0)
		return;

	stream = _stream;
	toRead = _toRead;

	/*
	 * Get the number of consumed bytes and directly read from the
	 * compressed stream, to make skipping much faster.
	 */
	if ([_decompressedStream isKindOfClass:
	    [OFLHAArchive_LHStream class]]) {
		OFLHAArchive_LHStream *LHStream = _decompressedStream;

		[LHStream close];
		toRead = [_entry compressedSize] - LHStream->_bytesConsumed;

		stream = _stream;
	}

	if ([stream isKindOfClass: [OFSeekableStream class]] &&
	    (sizeof(of_offset_t) > 4 || toRead < INT32_MAX))
		[stream seekToOffset: (of_offset_t)toRead
			      whence: SEEK_CUR];
	else {
		while (toRead > 0) {
			char buffer[512];
			size_t min = toRead;

			if (min > 512)
				min = 512;

			toRead -= [stream readIntoBuffer: buffer
						  length: min];
		}
	}

	_toRead = 0;
}

- (void)close
{
	[self of_skip];

	[_stream release];
	_stream = nil;



	[_decompressedStream release];




	_decompressedStream = nil;










	[super close];


}





@end