ObjFW  Diff

	[data increaseCountBy: 2];

	[data addItems: [_compressionMethod
			    cStringWithEncoding: OF_STRING_ENCODING_ASCII]
		 count: 5];

	tmp32 = OF_BSWAP32_IF_BE(_compressedSize);
	[data addItems: &tmp32
	[data addItems: &tmp32 count: sizeof(tmp32)];
		 count: sizeof(tmp32)];

	tmp32 = OF_BSWAP32_IF_BE(_uncompressedSize);
	[data addItems: &tmp32
	[data addItems: &tmp32 count: sizeof(tmp32)];
		 count: sizeof(tmp32)];

	tmp32 = OF_BSWAP32_IF_BE((uint32_t)_date.timeIntervalSince1970);
	[data addItems: &tmp32
	[data addItems: &tmp32 count: sizeof(tmp32)];
		 count: sizeof(tmp32)];

	/* Reserved */
	[data increaseCountBy: 1];

	/* Header level */
	[data addItem: "\x02"];

	/* CRC16 */
	tmp16 = OF_BSWAP16_IF_BE(_CRC16);
	[data addItems: &tmp16
	[data addItems: &tmp16 count: sizeof(tmp16)];
		 count: sizeof(tmp16)];

	/* Operating system identifier */
	[data addItem: "U"];

	/* Common header. Contains CRC16, which is written at the end. */
	tmp16 = OF_BSWAP16_IF_BE(5);
	[data addItems: &tmp16
	[data addItems: &tmp16 count: sizeof(tmp16)];
		 count: sizeof(tmp16)];
	[data addItem: "\x00"];
	[data increaseCountBy: 2];

	tmp16 = OF_BSWAP16_IF_BE((uint16_t)fileNameLength + 3);
	[data addItems: &tmp16
	[data addItems: &tmp16 count: sizeof(tmp16)];
		 count: sizeof(tmp16)];
	[data addItem: "\x01"];
	[data addItems: fileName
	[data addItems: fileName count: fileNameLength];
		 count: fileNameLength];

	if (directoryNameLength > 0) {
		tmp16 = OF_BSWAP16_IF_BE((uint16_t)directoryNameLength + 3);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
		[data addItem: "\x02"];
		[data addItems: directoryName
		[data addItems: directoryName count: directoryNameLength];
			 count: directoryNameLength];
	}

	if (_fileComment != nil) {
		size_t fileCommentLength =
		    [_fileComment cStringLengthWithEncoding: encoding];

		if (fileCommentLength > UINT16_MAX - 3)
			@throw [OFOutOfRangeException exception];

		tmp16 = OF_BSWAP16_IF_BE((uint16_t)fileCommentLength + 3);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
		[data addItem: "\x3F"];
		[data addItems: [_fileComment cStringWithEncoding: encoding]
			 count: fileCommentLength];
	}

	if (_mode != nil) {
		tmp16 = OF_BSWAP16_IF_BE(5);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
		[data addItem: "\x50"];

		tmp16 = OF_BSWAP16_IF_BE(_mode.unsignedShortValue);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
	}

	if (_UID != nil || _GID != nil) {
		if (_UID == nil || _GID == nil)
			@throw [OFInvalidArgumentException exception];

		tmp16 = OF_BSWAP16_IF_BE(7);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
		[data addItem: "\x51"];

		tmp16 = OF_BSWAP16_IF_BE(_GID.unsignedShortValue);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];

		tmp16 = OF_BSWAP16_IF_BE(_UID.unsignedShortValue);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
	}

	if (_group != nil) {
		size_t groupLength =
		    [_group cStringLengthWithEncoding: encoding];

		if (groupLength > UINT16_MAX - 3)
			@throw [OFOutOfRangeException exception];

		tmp16 = OF_BSWAP16_IF_BE((uint16_t)groupLength + 3);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
		[data addItem: "\x52"];
		[data addItems: [_group cStringWithEncoding: encoding]
			 count: groupLength];
	}

	if (_owner != nil) {
		size_t ownerLength =
		    [_owner cStringLengthWithEncoding: encoding];

		if (ownerLength > UINT16_MAX - 3)
			@throw [OFOutOfRangeException exception];

		tmp16 = OF_BSWAP16_IF_BE((uint16_t)ownerLength + 3);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
		[data addItem: "\x53"];
		[data addItems: [_owner cStringWithEncoding: encoding]
			 count: ownerLength];
	}

	if (_modificationDate != nil) {
		tmp16 = OF_BSWAP16_IF_BE(7);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
		[data addItem: "\x54"];

		tmp32 = OF_BSWAP32_IF_BE(
		    (uint32_t)_modificationDate.timeIntervalSince1970);
		[data addItems: &tmp32
		[data addItems: &tmp32 count: sizeof(tmp32)];
			 count: sizeof(tmp32)];
	}

	for (OFData *extension in _extensions) {
		size_t extensionLength = extension.count;

		if (extension.itemSize != 1)
			@throw [OFInvalidArgumentException exception];

		if (extensionLength > UINT16_MAX - 2)
			@throw [OFOutOfRangeException exception];

		tmp16 = OF_BSWAP16_IF_BE((uint16_t)extensionLength + 2);
		[data addItems: &tmp16
		[data addItems: &tmp16 count: sizeof(tmp16)];
			 count: sizeof(tmp16)];
		[data addItems: extension.items
		[data addItems: extension.items count: extension.count];
			 count: extension.count];
	}

	/* Zero-length extension to terminate */
	[data increaseCountBy: 2];

	headerSize = data.count;