ObjFW  Check-in [53e46a8326]

+ (instancetype)archiveWithPath: (OFString*)path;

/*!
 * @brief Initializes an already allocated OFZIPArchive object for the
 *	  specified file.
 *
 * @param path The path to the ZIP file
 * @return An initialized OFZIPArchive
 */
- initWithPath: (OFString*)path;

/*!
 * @brief Returns the entries in the central directory of the archive as a
 * 	  dictionary.
 *

#import "OFZIPArchive.h"
#import "OFZIPArchiveEntry.h"
#import "OFZIPArchiveEntry+Private.h"
#import "OFDataArray.h"
#import "OFDictionary.h"
#import "OFFile.h"
#import "OFDeflateStream.h"

#import "OFChecksumFailedException.h"
#import "OFInvalidArgumentException.h"
#import "OFInvalidFormatException.h"
#import "OFNotImplementedException.h"
#import "OFOpenFileFailedException.h"
#import "OFReadFailedException.h"
#import "OFUnsupportedVersionException.h"

#import "autorelease.h"
#import "macros.h"

#define CRC32_MAGIC 0xEDB88320

/*
 * FIXME: Current limitations:


 *  - Split archives are not supported.
 *  - Write support is missing.
 *  - The ZIP has to be a file on the local file system.
 *  - No support for ZIP64.
 *  - Encrypted files cannot be read.
 */

@interface OFZIPArchive (OF_PRIVATE_CATEGORY)
- (void)OF_readZIPInfo;
- (void)OF_readEntries;
@end

- initWithFile: (OFFile*)file;
- (bool)matchesEntry: (OFZIPArchiveEntry*)entry;
@end

@interface OFZIPArchive_FileStream: OFStream
{
	OFStream *_stream;
	OFFile *_file;
	OFZIPArchive_LocalFileHeader *_localFileHeader;
	bool _hasDataDescriptor;
	size_t _size;
	uint32_t _CRC32;
	bool _atEndOfStream;
}

- initWithArchiveFile: (OFString*)path
	       offset: (off_t)offset
      localFileHeader: (OFZIPArchive_LocalFileHeader*)localFileHeader;

@end

static uint32_t
crc32(uint32_t crc, uint8_t *bytes, size_t length)
{
	size_t i;

}

@implementation OFZIPArchive
+ (instancetype)archiveWithPath: (OFString*)path
{
	return [[[self alloc] initWithPath: path] autorelease];
}

- init
{
	@try {
		[self doesNotRecognizeSelector: _cmd];
	} @catch (id e) {
		[self release];
		@throw e;
	}

	abort();
}

- initWithPath: (OFString*)path
{
	self = [super init];

	@try {
		_file = [[OFFile alloc] initWithPath: path

		     whence: SEEK_SET];
	localFileHeader = [[[OFZIPArchive_LocalFileHeader alloc]
	    initWithFile: _file] autorelease];

	if (![localFileHeader matchesEntry: entry])
		@throw [OFInvalidFormatException exception];

	if (localFileHeader->_minVersion > 20) {
		OFString *version = [OFString stringWithFormat: @"%u.%u",
		    localFileHeader->_minVersion / 10,
		    localFileHeader->_minVersion % 10];

		@throw [OFUnsupportedVersionException
		    exceptionWithVersion: version];
	}





	ret = [[OFZIPArchive_FileStream alloc]
	    initWithArchiveFile: _path
			 offset: [_file seekToOffset: 0
					      whence: SEEK_CUR]

	        localFileHeader: localFileHeader];

	objc_autoreleasePoolPop(pool);

	return [ret autorelease];
}
@end

- (bool)matchesEntry: (OFZIPArchiveEntry*)entry
{
	if (_minVersion != [entry OF_minVersion] ||
	    _generalPurposeBitFlag != [entry OF_generalPurposeBitFlag] ||
	    _compressionMethod != [entry OF_compressionMethod] ||
	    _lastModifiedFileTime != [entry OF_lastModifiedFileTime] ||
	    _lastModifiedFileDate != [entry OF_lastModifiedFileDate])
		return false;

	if (!(_generalPurposeBitFlag & (1 << 3)))
		if (_CRC32 != [entry CRC32] ||
		    _compressedSize != [entry compressedSize] ||
		    _uncompressedSize != [entry uncompressedSize])
			return false;

	if (![_fileName isEqual: [entry fileName]])
		return false;

	return true;
}

@end

@implementation OFZIPArchive_FileStream
- initWithArchiveFile: (OFString*)path
	       offset: (off_t)offset
      localFileHeader: (OFZIPArchive_LocalFileHeader*)localFileHeader

{
	self = [super init];

	@try {
		_file = [[OFFile alloc] initWithPath: path
						mode: @"rb"];
		[_file seekToOffset: offset
			     whence: SEEK_SET];

		switch (localFileHeader->_compressionMethod) {
		case 0: /* No compression */
			_stream = [_file retain];
			break;
		case 8: /* Deflate */
			_stream = [[OFDeflateStream alloc]
			    initWithStream: _file];
			break;
		default:
			@throw [OFNotImplementedException
			    exceptionWithSelector: _cmd
					   object: self];
		}

		_localFileHeader = [localFileHeader retain];
		_hasDataDescriptor = (localFileHeader->_generalPurposeBitFlag &
		    (1 << 3));
		_size = localFileHeader->_uncompressedSize;
		_CRC32 = ~0;

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

	return self;
}

- (void)dealloc
{
	[_stream release];
	[_file release];
	[_localFileHeader release];

	[super dealloc];
}

- (bool)lowlevelIsAtEndOfStream
{
	return _atEndOfStream;
}

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

	if (_atEndOfStream)
		@throw [OFReadFailedException exceptionWithStream: self
						  requestedLength: length];

	if (_hasDataDescriptor) {
		if ([_stream isAtEndOfStream]) {
			uint32_t CRC32;

			_atEndOfStream = true;

			CRC32 = [_file readLittleEndianInt32];
			if (CRC32 == 0x08074B50)
				CRC32 = [_file readLittleEndianInt32];

			if (~_CRC32 != CRC32)
				@throw [OFChecksumFailedException exception];

			return 0;
		}


		ret = [_stream readIntoBuffer: buffer
				       length: length];
	} else {
		if (_size == 0) {
			_atEndOfStream = true;

			if (~_CRC32 != _localFileHeader->_CRC32)
				@throw [OFChecksumFailedException exception];

			return 0;
		}

		min = (length < _size ? length : _size);
		ret = [_stream readIntoBuffer: buffer
				       length: min];
		_size -= ret;
	}

	_CRC32 = crc32(_CRC32, buffer, ret);

	return ret;
}
@end