ObjFW  Diff

/*
 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017,
 *               2018, 2019, 2020
 *   Jonathan Schleifer <js@nil.im>
 * Copyright (c) 2008-2021 Jonathan Schleifer <js@nil.im>
 *
 * All rights reserved.
 *
 * This file is part of ObjFW. It may be distributed under the terms of the
 * Q Public License 1.0, which can be found in the file LICENSE.QPL included in
 * the packaging of this file.
 *

#import "OFNotOpenException.h"
#import "OFTruncatedDataException.h"

@implementation OFGZIPStream
@synthesize operatingSystemMadeOn = _operatingSystemMadeOn;
@synthesize modificationDate = _modificationDate;

+ (instancetype)streamWithStream: (OFStream *)stream
+ (instancetype)streamWithStream: (OFStream *)stream mode: (OFString *)mode
			    mode: (OFString *)mode
{
	return [[[self alloc] initWithStream: stream
	return [[[self alloc] initWithStream: stream mode: mode] autorelease];
					mode: mode] autorelease];
}

- (instancetype)init
{
	OF_INVALID_INIT_METHOD
}

- (instancetype)initWithStream: (OFStream *)stream
- (instancetype)initWithStream: (OFStream *)stream mode: (OFString *)mode
			  mode: (OFString *)mode
{
	self = [super init];

	@try {
		if (![mode isEqual: @"r"])
			@throw [OFNotImplementedException
			    exceptionWithSelector: _cmd

	[_inflateStream release];
	[_modificationDate release];

	[super dealloc];
}

- (size_t)lowlevelReadIntoBuffer: (void *)buffer
- (size_t)lowlevelReadIntoBuffer: (void *)buffer length: (size_t)length
			  length: (size_t)length
{
	if (_stream == nil)
		@throw [OFNotOpenException exceptionWithObject: self];

	for (;;) {
		uint8_t byte;
		uint32_t CRC32, uncompressedSize;

		if (_stream.atEndOfStream) {
			if (_state != OF_GZIP_STREAM_ID1)
				@throw [OFTruncatedDataException exception];

			return 0;
		}

		switch (_state) {
		case OF_GZIP_STREAM_ID1:
		case OF_GZIP_STREAM_ID2:
		case OF_GZIP_STREAM_COMPRESSION_METHOD:
			if ([_stream readIntoBuffer: &byte
			if ([_stream readIntoBuffer: &byte length: 1] < 1)
					     length: 1] < 1)
				return 0;

			if ((_state == OF_GZIP_STREAM_ID1 && byte != 0x1F) ||
			    (_state == OF_GZIP_STREAM_ID2 && byte != 0x8B) ||
			    (_state == OF_GZIP_STREAM_COMPRESSION_METHOD &&
			    byte != 8))
				@throw [OFInvalidFormatException exception];

			_state++;
			break;
		case OF_GZIP_STREAM_FLAGS:
			if ([_stream readIntoBuffer: &byte
			if ([_stream readIntoBuffer: &byte length: 1] < 1)
					     length: 1] < 1)
				return 0;

			_flags = byte;
			_state++;
			break;
		case OF_GZIP_STREAM_MODIFICATION_TIME:
			_bytesRead += [_stream

			    (_buffer[3] << 24) | (_buffer[2] << 16) |
			    (_buffer[1] << 8) | _buffer[0]];

			_bytesRead = 0;
			_state++;
			break;
		case OF_GZIP_STREAM_EXTRA_FLAGS:
			if ([_stream readIntoBuffer: &byte
			if ([_stream readIntoBuffer: &byte length: 1] < 1)
					     length: 1] < 1)
				return 0;

			_extraFlags = byte;
			_state++;
			break;
		case OF_GZIP_STREAM_OPERATING_SYSTEM:
			if ([_stream readIntoBuffer: &byte
			if ([_stream readIntoBuffer: &byte length: 1] < 1)
					     length: 1] < 1)
				return 0;

			_operatingSystemMadeOn = byte;
			_state++;
			break;
		case OF_GZIP_STREAM_EXTRA_LENGTH:
			if (!(_flags & OF_GZIP_STREAM_FLAG_EXTRA)) {