func readInt(b []byte, off, size uintptr) (u uint64, ok bool) {
	if len(b) < int(off+size) {
		return 0, false
	}
	return readIntLE(b[off:], size), true
}

func readIntLE(b []byte, size uintptr) uint64 {
	switch size {
	case 1:
		return uint64(b[0])
	case 2:
		return uint64(byteorder.LeUint16(b))
	case 4:
		return uint64(byteorder.LeUint32(b))
	case 8: