aboutsummaryrefslogtreecommitdiffstats
path: root/golib/filepath.go
blob: 1817f583bad2d86e7505fd53c4c473dc82c4767f (plain)
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
package common

import (
	"fmt"
	"os"
	"os/user"
	"path"
	"path/filepath"
	"regexp"
	"runtime"
	"strings"
)

// Exists returns whether the given file or directory exists or not
func Exists(path string) bool {
	_, err := os.Stat(path)
	if err == nil {
		return true
	}
	if os.IsNotExist(err) {
		return false
	}
	return true
}

// IsDir returns true when the given path is a directory
func IsDir(path string) bool {
	fi, err := os.Stat(path)
	if err != nil {
		return false
	}

	return fi.Mode().IsDir()
}

// ResolveEnvVar Resolved environment variable regarding the syntax ${MYVAR}
// or $MYVAR following by a slash or a backslash
func ResolveEnvVar(s string) (string, error) {
	if s == "" {
		return s, nil
	}

	// Resolved tilde : ~/
	if len(s) > 2 && s[:2] == "~/" {
		if usr, err := user.Current(); err == nil {
			s = filepath.Join(usr.HomeDir, s[2:])
		}
	}

	// Resolved ${MYVAR}
	re := regexp.MustCompile("\\${([^}]+)}")
	vars := re.FindAllStringSubmatch(s, -1)
	res := s
	for _, v := range vars {
		val := ""
		if v[1] == "EXEPATH" {
			// Specific case to resolve $EXEPATH or ${EXEPATH} used as current executable path
			val = GetExePath()

		} else {
			// Get env var value
			val = os.Getenv(v[1])
			if val == "" {
				// Specific case to resolved $HOME or ${HOME} on Windows host
				if runtime.GOOS == "windows" && v[1] == "HOME" {
					if usr, err := user.Current(); err == nil {
						val = usr.HomeDir
					}
				} else {
					return res, fmt.Errorf("ERROR: %s env variable not defined", v[1])
				}
			}
		}

		rer := regexp.MustCompile("\\${" + v[1] + "}")
		res = rer.ReplaceAllString(res, val)
	}

	// Resolved $MYVAR following by a slash (or a backslash for Windows)
	// TODO
	//re := regexp.MustCompile("\\$([^\\/])+/")

	return path.Clean(res), nil
}

// PathNormalize normalizes a linux or windows like path
func PathNormalize(p string) string {
	sep := string(filepath.Separator)
	if sep != "/" {
		return p
	}
	// Replace drive like C: by C/
	res := p
	if p[1:2] == ":" {
		res = p[0:1] + sep + p[2:]
	}
	res = strings.Replace(res, "\\", "/", -1)
	return filepath.Clean(res)
}

// GetUserHome returns the user's home directory or empty string on error
func GetUserHome() string {
	if usr, err := user.Current(); err == nil && usr != nil && usr.HomeDir != "" {
		return usr.HomeDir
	}
	for _, p := range []string{"HOME", "HomePath"} {
		if h := os.Getenv(p); h != "" {
			return h
		}
	}

	return ""
}

// GetExePath returns the full path of the current executable
func GetExePath() string {
	exePath := os.Args[0] // set fallback value
	ee, _ := os.Executable()
	exeAbsPath, err := filepath.Abs(ee)
	if err == nil {
		exePath, err = filepath.EvalSymlinks(exeAbsPath)
		if err == nil {
			exePath = filepath.Dir(ee)
		} else {
			exePath = filepath.Dir(exeAbsPath)
		}
	}
	return exePath
}