d

broker/packet.go

@@ -0,0 +1,60 @@
+package broker
+
+import (
+	"errors"
+	"io"
+	"net"
+
+	log "github.com/cihub/seelog"
+)
+
+func checkError(desc string, err error) {
+	if err != nil {
+		log.Error(desc, " : ", err)
+	}
+}
+func ReadPacket(conn net.Conn) ([]byte, error) {
+	if conn == nil {
+		return nil, errors.New("conn is null")
+	}
+	// conn.SetReadDeadline(t)
+	var buf []byte
+	// read fix header
+	b := make([]byte, 1)
+	_, err := io.ReadFull(conn, b)
+	if err != nil {
+		return nil, err
+	}
+	buf = append(buf, b...)
+	// read rem msg length
+	rembuf, remlen := decodeLength(conn)
+	buf = append(buf, rembuf...)
+	// read rem msg
+	packetBytes := make([]byte, remlen)
+	_, err = io.ReadFull(conn, packetBytes)
+	if err != nil {
+		return nil, err
+	}
+	buf = append(buf, packetBytes...)
+	// log.Info("len buf: ", len(buf))
+	return buf, nil
+}
+
+func decodeLength(r io.Reader) ([]byte, int) {
+	var rLength uint32
+	var multiplier uint32
+	var buf []byte
+	b := make([]byte, 1)
+	for {
+		io.ReadFull(r, b)
+		digit := b[0]
+		buf = append(buf, b[0])
+		rLength |= uint32(digit&127) << multiplier
+		if (digit & 128) == 0 {
+			break
+		}
+		multiplier += 7
+
+	}
+	return buf, int(rLength)
+}