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
|
// package util defines public utility functions to be used by applications
// these are outside of the client package as they can be used even if a client hasn't been created yet
package util
import (
"net"
"strings"
"codeberg.org/eduVPN/eduvpn-common/i18nerr"
)
// CalculateGateway takes a CIDR encoded subnet `cidr` and returns the gateway and an error
func CalculateGateway(cidr string) (string, error) {
_, ipn, err := net.ParseCIDR(cidr)
if err != nil {
return "", i18nerr.WrapInternalf(err, "failed to parse CIDR for calculating gateway: %v", cidr)
}
ret := make(net.IP, len(ipn.IP))
copy(ret, ipn.IP)
for i := len(ret) - 1; i >= 0; i-- {
ret[i]++
if ret[i] > 0 {
break
}
}
if !ipn.Contains(ret) {
return "", i18nerr.Newf("IP network does not contain incremented IP: %v", ret)
}
return ret.String(), nil
}
// GetLanguageMatched uses a map from language tags to strings to extract the right language given the tag
// It implements it according to https://github.com/eduvpn/documentation/blob/dc4d53c47dd7a69e95d6650eec408e16eaa814a2/SERVER_DISCOVERY.md#language-matching
func GetLanguageMatched(langMap map[string]string, langTag string) string {
// If no map is given, return the empty string
if len(langMap) == 0 {
return ""
}
// Try to find the exact match
if val, ok := langMap[langTag]; ok {
return val
}
// Try to find a key that starts with the OS language setting
for k := range langMap {
if strings.HasPrefix(k, langTag) {
return langMap[k]
}
}
// Try to find a key that starts with the first part of the OS language (e.g. de-)
pts := strings.Split(langTag, "-")
// We have a "-"
if len(pts) > 1 {
for k := range langMap {
if strings.HasPrefix(k, pts[0]+"-") {
return langMap[k]
}
}
}
// search for just the language (e.g. de)
for k := range langMap {
if k == pts[0] {
return langMap[k]
}
}
// Pick one that is deemed best, e.g. en-US or en, but note that not all languages are always available!
// We force an entry that is english exactly or with an english prefix
for k := range langMap {
if k == "en" || strings.HasPrefix(k, "en-") {
return langMap[k]
}
}
// Otherwise just return one
for k := range langMap {
return langMap[k]
}
return ""
}
|
