}
			if hdr.Typeflag == TypeXGlobalHeader {
				mergePAX(hdr, paxHdrs)
				return &Header{
					Name:       hdr.Name,
					Typeflag:   hdr.Typeflag,
					Xattrs:     hdr.Xattrs,
					PAXRecords: hdr.PAXRecords,
					Format:     format,
				}, nil
			}
			continue // This is a meta header affecting the next header
		case TypeGNULongName, TypeGNULongLink:
			format.mayOnlyBe(FormatGNU)

	}
	b = b[22:] // skip over most of the header
	filenameLen := int(b.uint16())
	extraLen := int(b.uint16())
	return int64(fileHeaderLen + filenameLen + extraLen), nil
}

// readDirectoryHeader attempts to read a directory header from r.
// It returns io.ErrUnexpectedEOF if it cannot read a complete header,
// and ErrFormat if it doesn't find a valid header signature.

	size       int64
	actualSize int64

	checksum      etag.ETag
	contentSHA256 []byte

	// Content checksum
	contentHash   Checksum
	contentHasher hash.Hash
	disableMD5    bool

	trailer http.Header

	sha256 hash.Hash
}

// Options are optional arguments to NewReaderWithOpts, Options
// simply converts positional arguments to NewReader() into a
// more flexible way to provide optional inputs. This is currently