Function UnmarshalMACPayload

pkg/encoding/lorawan/messages.go:161–187

UnmarshalMACPayload unmarshals b into msg.

(b []byte, msg *ttnpb.MACPayload, isUplink bool)

// UnmarshalMACPayload unmarshals b into msg.
func UnmarshalMACPayload(b []byte, msg *ttnpb.MACPayload, isUplink bool) error {
	n := uint8(len(b))
	if n < 7 {
		return errExpectedLengthHigherOrEqual("FHDR", 7)(n)
	}
	fOptsLen := b[4] & 0xf
	fhdrLen := fOptsLen + 7
	if n < fhdrLen {
		return errExpectedLengthHigherOrEqual("MACPayload", fhdrLen)(n)
	}
	msg.FHdr = &ttnpb.FHDR{}
	if err := UnmarshalFHDR(b[0:fhdrLen], msg.FHdr, isUplink); err != nil {
		return errFailedDecoding("FHDR").WithCause(err)
	}

	fPortIdx := fhdrLen
	if n > fPortIdx {
		msg.FPort = uint32(b[fPortIdx])

		frmPayloadIdx := fPortIdx + 1
		if n > frmPayloadIdx {
			msg.FrmPayload = make([]byte, 0, n-frmPayloadIdx)
			msg.FrmPayload = append(msg.FrmPayload, b[frmPayloadIdx:]...)
		}
	}
	return nil
}

// AppendDLSettings appends encoded msg to dst.
func AppendDLSettings(dst []byte, msg *ttnpb.DLSettings) ([]byte, error) {