OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-dev/] [or1k-gcc/] [libgo/] [go/] [net/] [dnsconfig.go] - Blame information for rev 760

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 747 jeremybenn
// Copyright 2009 The Go Authors. All rights reserved.
2
// Use of this source code is governed by a BSD-style
3
// license that can be found in the LICENSE file.
4
 
5
// +build darwin freebsd linux netbsd openbsd
6
 
7
// Read system DNS config from /etc/resolv.conf
8
 
9
package net
10
 
11
type dnsConfig struct {
12
        servers  []string // servers to use
13
        search   []string // suffixes to append to local name
14
        ndots    int      // number of dots in name to trigger absolute lookup
15
        timeout  int      // seconds before giving up on packet
16
        attempts int      // lost packets before giving up on server
17
        rotate   bool     // round robin among servers
18
}
19
 
20
// See resolv.conf(5) on a Linux machine.
21
// TODO(rsc): Supposed to call uname() and chop the beginning
22
// of the host name to get the default search domain.
23
// We assume it's in resolv.conf anyway.
24
func dnsReadConfig() (*dnsConfig, error) {
25
        file, err := open("/etc/resolv.conf")
26
        if err != nil {
27
                return nil, &DNSConfigError{err}
28
        }
29
        conf := new(dnsConfig)
30
        conf.servers = make([]string, 3)[0:0] // small, but the standard limit
31
        conf.search = make([]string, 0)
32
        conf.ndots = 1
33
        conf.timeout = 5
34
        conf.attempts = 2
35
        conf.rotate = false
36
        for line, ok := file.readLine(); ok; line, ok = file.readLine() {
37
                f := getFields(line)
38
                if len(f) < 1 {
39
                        continue
40
                }
41
                switch f[0] {
42
                case "nameserver": // add one name server
43
                        a := conf.servers
44
                        n := len(a)
45
                        if len(f) > 1 && n < cap(a) {
46
                                // One more check: make sure server name is
47
                                // just an IP address.  Otherwise we need DNS
48
                                // to look it up.
49
                                name := f[1]
50
                                switch len(ParseIP(name)) {
51
                                case 16:
52
                                        name = "[" + name + "]"
53
                                        fallthrough
54
                                case 4:
55
                                        a = a[0 : n+1]
56
                                        a[n] = name
57
                                        conf.servers = a
58
                                }
59
                        }
60
 
61
                case "domain": // set search path to just this domain
62
                        if len(f) > 1 {
63
                                conf.search = make([]string, 1)
64
                                conf.search[0] = f[1]
65
                        } else {
66
                                conf.search = make([]string, 0)
67
                        }
68
 
69
                case "search": // set search path to given servers
70
                        conf.search = make([]string, len(f)-1)
71
                        for i := 0; i < len(conf.search); i++ {
72
                                conf.search[i] = f[i+1]
73
                        }
74
 
75
                case "options": // magic options
76
                        for i := 1; i < len(f); i++ {
77
                                s := f[i]
78
                                switch {
79
                                case len(s) >= 6 && s[0:6] == "ndots:":
80
                                        n, _, _ := dtoi(s, 6)
81
                                        if n < 1 {
82
                                                n = 1
83
                                        }
84
                                        conf.ndots = n
85
                                case len(s) >= 8 && s[0:8] == "timeout:":
86
                                        n, _, _ := dtoi(s, 8)
87
                                        if n < 1 {
88
                                                n = 1
89
                                        }
90
                                        conf.timeout = n
91
                                case len(s) >= 8 && s[0:9] == "attempts:":
92
                                        n, _, _ := dtoi(s, 9)
93
                                        if n < 1 {
94
                                                n = 1
95
                                        }
96
                                        conf.attempts = n
97
                                case s == "rotate":
98
                                        conf.rotate = true
99
                                }
100
                        }
101
                }
102
        }
103
        file.close()
104
 
105
        return conf, nil
106
}

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.