forked from mailru/easyjson
/
pkgpath.go
171 lines (144 loc) · 3.38 KB
/
pkgpath.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
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
package parser
import (
"bytes"
"fmt"
"io/ioutil"
"os"
"os/exec"
"path"
"path/filepath"
"strconv"
"strings"
"sync"
)
func getPkgPath(fname string, isDir bool) (string, error) {
if !filepath.IsAbs(fname) {
pwd, err := os.Getwd()
if err != nil {
return "", err
}
fname = filepath.Join(pwd, fname)
}
goModPath, _ := goModPath(fname, isDir)
if strings.Contains(goModPath, "go.mod") {
pkgPath, err := getPkgPathFromGoMod(fname, isDir, goModPath)
if err != nil {
return "", err
}
return pkgPath, nil
}
return getPkgPathFromGOPATH(fname, isDir)
}
var goModPathCache = struct {
paths map[string]string
sync.RWMutex
}{
paths: make(map[string]string),
}
// empty if no go.mod, GO111MODULE=off or go without go modules support
func goModPath(fname string, isDir bool) (string, error) {
root := fname
if !isDir {
root = filepath.Dir(fname)
}
goModPathCache.RLock()
goModPath, ok := goModPathCache.paths[root]
goModPathCache.RUnlock()
if ok {
return goModPath, nil
}
defer func() {
goModPathCache.Lock()
goModPathCache.paths[root] = goModPath
goModPathCache.Unlock()
}()
cmd := exec.Command("go", "env", "GOMOD")
cmd.Dir = root
stdout, err := cmd.Output()
if err != nil {
return "", err
}
goModPath = string(bytes.TrimSpace(stdout))
return goModPath, nil
}
func getPkgPathFromGoMod(fname string, isDir bool, goModPath string) (string, error) {
modulePath := getModulePath(goModPath)
if modulePath == "" {
return "", fmt.Errorf("cannot determine module path from %s", goModPath)
}
rel := path.Join(modulePath, filePathToPackagePath(strings.TrimPrefix(fname, filepath.Dir(goModPath))))
if !isDir {
return path.Dir(rel), nil
}
return path.Clean(rel), nil
}
var (
modulePrefix = []byte("\nmodule ")
pkgPathFromGoModCache = make(map[string]string)
)
func getModulePath(goModPath string) string {
pkgPath, ok := pkgPathFromGoModCache[goModPath]
if ok {
return pkgPath
}
defer func() {
pkgPathFromGoModCache[goModPath] = pkgPath
}()
data, err := ioutil.ReadFile(goModPath)
if err != nil {
return ""
}
var i int
if bytes.HasPrefix(data, modulePrefix[1:]) {
i = 0
} else {
i = bytes.Index(data, modulePrefix)
if i < 0 {
return ""
}
i++
}
line := data[i:]
// Cut line at \n, drop trailing \r if present.
if j := bytes.IndexByte(line, '\n'); j >= 0 {
line = line[:j]
}
if line[len(line)-1] == '\r' {
line = line[:len(line)-1]
}
line = line[len("module "):]
// If quoted, unquote.
pkgPath = strings.TrimSpace(string(line))
if pkgPath != "" && pkgPath[0] == '"' {
s, err := strconv.Unquote(pkgPath)
if err != nil {
return ""
}
pkgPath = s
}
return pkgPath
}
func getPkgPathFromGOPATH(fname string, isDir bool) (string, error) {
gopath := os.Getenv("GOPATH")
if gopath == "" {
var err error
gopath, err = getDefaultGoPath()
if err != nil {
return "", fmt.Errorf("cannot determine GOPATH: %s", err)
}
}
for _, p := range strings.Split(gopath, string(filepath.ListSeparator)) {
prefix := filepath.Join(p, "src") + string(filepath.Separator)
if rel := strings.TrimPrefix(fname, prefix); rel != fname {
if !isDir {
return path.Dir(filePathToPackagePath(rel)), nil
} else {
return path.Clean(filePathToPackagePath(rel)), nil
}
}
}
return "", fmt.Errorf("file '%v' is not in GOPATH", fname)
}
func filePathToPackagePath(path string) string {
return filepath.ToSlash(path)
}