Temporarily add go-agentx (w/ fixes to lexico ordering)

go-agentx/pdu/header_packet.go

@@ -0,0 +1,38 @@
+// Copyright 2018 The agentx authors
+// Licensed under the LGPLv3 with static-linking exception.
+// See LICENCE file for details.
+
+package pdu
+
+import (
+	"fmt"
+)
+
+// HeaderPacket defines a container structure for a header and a packet.
+type HeaderPacket struct {
+	Header *Header
+	Packet Packet
+}
+
+// MarshalBinary returns the pdu packet as a slice of bytes.
+func (hp *HeaderPacket) MarshalBinary() ([]byte, error) {
+	payloadBytes, err := hp.Packet.MarshalBinary()
+	if err != nil {
+		return nil, err
+	}
+
+	hp.Header.Version = 1
+	hp.Header.Type = hp.Packet.Type()
+	hp.Header.PayloadLength = uint32(len(payloadBytes))
+
+	result, err := hp.Header.MarshalBinary()
+	if err != nil {
+		return nil, err
+	}
+
+	return append(result, payloadBytes...), nil
+}
+
+func (hp *HeaderPacket) String() string {
+	return fmt.Sprintf("[head %v, body %v]", hp.Header, hp.Packet)
+}