forked from rumblefrog/go-a2s
/
client.go
138 lines (106 loc) · 2.14 KB
/
client.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
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
package a2s
import (
"errors"
"fmt"
"net"
"strings"
"time"
)
const (
DefaultTimeout = time.Second * 3
DefaultPort = 27015
)
var (
ErrNilOption = errors.New("Invalid client option")
)
type Client struct {
addr string
conn net.Conn
timeout time.Duration
buffer [MaxPacketSize]byte
preOrange bool
appid AppID
wait time.Duration
next time.Time
}
func TimeoutOption(timeout time.Duration) func(*Client) error {
return func(c *Client) error {
c.timeout = timeout
return nil
}
}
func PreOrangeBox(pre bool) func(*Client) error {
return func(c *Client) error {
c.preOrange = pre
return nil
}
}
func SetAppID(appid int32) func(*Client) error {
return func(c *Client) error {
c.appid = AppID(appid)
return nil
}
}
func NewClient(addr string, options ...func(*Client) error) (c *Client, err error) {
c = &Client{
timeout: DefaultTimeout,
addr: addr,
}
for _, f := range options {
if f == nil {
return nil, ErrNilOption
}
if err = f(c); err != nil {
return nil, err
}
}
if !strings.Contains(c.addr, ":") {
c.addr = fmt.Sprintf("%s:%d", c.addr, DefaultPort)
}
if c.conn, err = net.DialTimeout("udp", c.addr, c.timeout); err != nil {
return nil, err
}
return c, nil
}
func (c *Client) send(data []byte) error {
c.enforceRateLimit()
defer c.setNextQueryTime()
if c.timeout > 0 {
c.conn.SetWriteDeadline(c.extendedDeadline())
}
_, err := c.conn.Write(data)
return err
}
func (c *Client) receive() ([]byte, error) {
defer c.setNextQueryTime()
if c.timeout > 0 {
c.conn.SetReadDeadline(c.extendedDeadline())
}
size, err := c.conn.Read(c.buffer[0:MaxPacketSize])
if err != nil {
return nil, err
}
buffer := make([]byte, size)
copy(buffer, c.buffer[:size])
return buffer, nil
}
func (c *Client) Close() error {
return c.conn.Close()
}
func (c *Client) extendedDeadline() time.Time {
return time.Now().Add(c.timeout)
}
func (c *Client) setNextQueryTime() {
if c.wait != 0 {
c.next = time.Now().Add(c.wait)
}
}
func (c *Client) enforceRateLimit() {
if c.wait == 0 {
return
}
wait := c.next.Sub(time.Now())
if wait > 0 {
time.Sleep(wait)
}
}