/
packet.go
101 lines (82 loc) · 1.87 KB
/
packet.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
package packet
import (
"bytes"
"encoding/binary"
"hash/crc32"
)
type Package struct {
}
//Pack 封包
func (this *Package) Pack(msg []byte) ([]byte, error) {
buf := new(bytes.Buffer)
startByte := []byte{33}
err := binary.Write(buf, binary.BigEndian, startByte)
if err != nil {
return nil, err
}
msgLength := uint32(len(msg))
err = binary.Write(buf, binary.BigEndian, msgLength)
if err != nil {
return nil, err
}
checkLength := this.CheckCRC32(msgLength)
err = binary.Write(buf, binary.BigEndian, checkLength)
if err != nil {
return nil, err
}
err = binary.Write(buf, binary.BigEndian, msg)
if err != nil {
return nil, err
}
endByte := []byte{10}
err = binary.Write(buf, binary.BigEndian, endByte)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
// UnPack 解包
func (this *Package) UnPack(buff []byte) ([]byte, error) {
buf := bytes.NewBuffer(buff)
startByte := make([]byte, 1)
err := binary.Read(buf, binary.BigEndian, &startByte)
if err != nil {
return nil, err
}
var msgLength uint32
err = binary.Read(buf, binary.BigEndian, &msgLength)
if err != nil {
return nil, err
}
var checkLength uint32
err = binary.Read(buf, binary.BigEndian, &checkLength)
if err != nil {
return nil, err
}
msg := make([]byte, msgLength)
err = binary.Read(buf, binary.BigEndian, &msg)
if err != nil {
return nil, err
}
endByte := make([]byte, 1)
err = binary.Read(buf, binary.BigEndian, &endByte)
if err != nil {
return nil, err
}
return msg, nil
}
// unPackMsgLength 解包长度
func (this *Package) UnPackMsgLength(buff []byte) (length uint32) {
buf := bytes.NewBuffer(buff)
err := binary.Read(buf, binary.BigEndian, &length)
if err != nil {
return 0
}
return
}
// checkCRC32 CRC校验
func (this *Package) CheckCRC32(l interface{}) uint32 {
ieee := crc32.NewIEEE()
binary.Write(ieee, binary.BigEndian, l)
return ieee.Sum32()
}