return x, buf, err
	}
	if x.versions < 0 {
		return x, buf, fmt.Errorf("decodeXLHeaders: Negative version count %d", x.versions)
	}
	return x, buf, nil
}

// decodeVersions will decode a number of versions from a buffer
// and perform a callback for each version in order, newest first.
// Any non-nil error is returned.
func decodeVersions(buf []byte, versions int, fn func(idx int, hdr, meta []byte) error) (err error) {