add MarshalBinary and UnmarshalBinary for VLAN and VLANs

Author: hujun-open

etherconn.go

@@ -153,6 +153,24 @@ type VLAN struct {
 	EtherType uint16
 }
 
+// MarshalBinary implements encoding.BinaryMarshaler interface
+func (vlan VLAN) MarshalBinary() (data []byte, err error) {
+	data = make([]byte, 4)
+	binary.BigEndian.PutUint16(data[:2], vlan.ID)
+	binary.BigEndian.PutUint16(data[2:4], vlan.EtherType)
+	return
+}
+
+// UnmarshalBinary implements encoding.BinaryUnmarshaler interface
+func (vlan *VLAN) UnmarshalBinary(data []byte) error {
+	if len(data) < 4 {
+		return fmt.Errorf("can't unmarshal VLAN from a byte slice less than 4 bytes")
+	}
+	vlan.ID = binary.BigEndian.Uint16(data[:2])
+	vlan.EtherType = binary.BigEndian.Uint16(data[2:4])
+	return nil
+}
+
 // VLANs is a slice of VLAN
 type VLANs []*VLAN
 
@@ -165,6 +183,31 @@ func (vlans VLANs) String() string {
 	return s
 }
 
+// MarshalBinary implements encoding.BinaryMarshaler interface
+func (vlans VLANs) MarshalBinary() (data []byte, err error) {
+	for _, v := range vlans {
+		b, _ := v.MarshalBinary()
+		data = append(data, b...)
+	}
+	return
+}
+
+// UnmarshalBinary implements encoding.BinaryUnmarshaler interface
+func (vlans *VLANs) UnmarshalBinary(data []byte) error {
+	if len(data) < 4 {
+		return fmt.Errorf("can't unmarshal VLANs from a byte slice less than 4 bytes")
+	}
+	*vlans = []*VLAN{}
+	for start := 0; start+4 <= len(data); start += 4 {
+		v := new(VLAN)
+		if err := v.UnmarshalBinary(data[start : start+4]); err != nil {
+			return err
+		}
+		*vlans = append(*vlans, v)
+	}
+	return nil
+}
+
 // MarshalText implements encoding.TextMarshaler interface
 func (vlans VLANs) MarshalText() (text []byte, err error) {
 	return []byte(vlans.String()), nil

etherconn_test.go

@@ -786,6 +786,7 @@ func TestRUDPConn(t *testing.T) {
 // newIDs is the value for SetIDs, newv is the new VLANs after setIDs
 type testVLANsCase struct {
 	v          etherconn.VLANs
+	vbs        []byte
 	vs         string
 	umvs       string
 	newIDs     []uint16
@@ -803,6 +804,7 @@ func TestVLANs(t *testing.T) {
 				},
 			},
 			vs:     "|300",
+			vbs:    []byte{0x1, 0x2c, 0x81, 0},
 			newIDs: []uint16{111},
 			newv: etherconn.VLANs{
 				&etherconn.VLAN{
@@ -881,6 +883,34 @@ func TestVLANs(t *testing.T) {
 					EtherType: 0x8200,
 				},
 			},
+			vbs:    []byte{0, 100, 0x81, 0, 0, 200, 0x82, 0},
+			vs:     "|100|200",
+			umvs:   "100|200",
+			newIDs: []uint16{111, 222},
+			newv: etherconn.VLANs{
+				&etherconn.VLAN{
+					ID:        111,
+					EtherType: 0x8100,
+				},
+				&etherconn.VLAN{
+					ID:        222,
+					EtherType: 0x8200,
+				},
+			},
+		},
+		{
+			shouldFail: true,
+			v: etherconn.VLANs{
+				&etherconn.VLAN{
+					ID:        100,
+					EtherType: 0x8100,
+				},
+				&etherconn.VLAN{
+					ID:        200,
+					EtherType: 0x8200,
+				},
+			},
+			vbs:    []byte{0, 100, 0x81, 0, 0, 200, 0x82},
 			vs:     "|100|200",
 			umvs:   "100|200",
 			newIDs: []uint16{111, 222},
@@ -922,6 +952,25 @@ func TestVLANs(t *testing.T) {
 		},
 	}
 	testFunc := func(c testVLANsCase) error {
+		if len(c.vbs) != 0 {
+			buf, err := c.v.MarshalBinary()
+			if err != nil {
+				return err
+			}
+			if !bytes.Equal(buf, c.vbs) {
+				return fmt.Errorf("%v marshalbinary result %v is different from expected %v", c.v, buf, c.vbs)
+			}
+			newv := new(etherconn.VLANs)
+			err = newv.UnmarshalBinary(buf)
+			if err != nil {
+				return err
+			}
+			if !newv.Equal(c.v) {
+				return fmt.Errorf("%v unmarshalbinary result %v is different", c.v, newv)
+			}
+
+		}
+
 		if c.v.String() != c.vs {
 			return fmt.Errorf("c.v string %v is different from expected %v", c.v.String(), c.vs)
 		}