packet

lib/message/puback.go

@@ -0,0 +1,109 @@
+// Copyright (c) 2014 The SurgeMQ Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package message
+
+import "fmt"
+
+// A PUBACK Packet is the response to a PUBLISH Packet with QoS level 1.
+type PubackMessage struct {
+	header
+}
+
+var _ Message = (*PubackMessage)(nil)
+
+// NewPubackMessage creates a new PUBACK message.
+func NewPubackMessage() *PubackMessage {
+	msg := &PubackMessage{}
+	msg.SetType(PUBACK)
+
+	return msg
+}
+
+func (this PubackMessage) String() string {
+	return fmt.Sprintf("%s, Packet ID=%d", this.header, this.packetId)
+}
+
+func (this *PubackMessage) Len() int {
+	if !this.dirty {
+		return len(this.dbuf)
+	}
+
+	ml := this.msglen()
+
+	if err := this.SetRemainingLength(int32(ml)); err != nil {
+		return 0
+	}
+
+	return this.header.msglen() + ml
+}
+
+func (this *PubackMessage) Decode(src []byte) (int, error) {
+	total := 0
+
+	n, err := this.header.decode(src[total:])
+	total += n
+	if err != nil {
+		return total, err
+	}
+
+	//this.packetId = binary.BigEndian.Uint16(src[total:])
+	this.packetId = src[total : total+2]
+	total += 2
+
+	this.dirty = false
+
+	return total, nil
+}
+
+func (this *PubackMessage) Encode(dst []byte) (int, error) {
+	if !this.dirty {
+		if len(dst) < len(this.dbuf) {
+			return 0, fmt.Errorf("puback/Encode: Insufficient buffer size. Expecting %d, got %d.", len(this.dbuf), len(dst))
+		}
+
+		return copy(dst, this.dbuf), nil
+	}
+
+	hl := this.header.msglen()
+	ml := this.msglen()
+
+	if len(dst) < hl+ml {
+		return 0, fmt.Errorf("puback/Encode: Insufficient buffer size. Expecting %d, got %d.", hl+ml, len(dst))
+	}
+
+	if err := this.SetRemainingLength(int32(ml)); err != nil {
+		return 0, err
+	}
+
+	total := 0
+
+	n, err := this.header.encode(dst[total:])
+	total += n
+	if err != nil {
+		return total, err
+	}
+
+	if copy(dst[total:total+2], this.packetId) != 2 {
+		dst[total], dst[total+1] = 0, 0
+	}
+	total += 2
+
+	return total, nil
+}
+
+func (this *PubackMessage) msglen() int {
+	// packet ID
+	return 2
+}