mirror of
https://github.com/criyle/go-sandbox.git
synced 2025-09-26 23:19:11 +08:00
64 lines
1.2 KiB
Go
64 lines
1.2 KiB
Go
package container
|
|
|
|
import (
|
|
"errors"
|
|
"io/fs"
|
|
"os"
|
|
"path/filepath"
|
|
"strings"
|
|
)
|
|
|
|
var (
|
|
errNotFound = errors.New("executable file not found in $PATH")
|
|
errNoPath = errors.New("no PATH environment variable provided for look up")
|
|
)
|
|
|
|
func findExecutable(file string) error {
|
|
d, err := os.Stat(file)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if m := d.Mode(); !m.IsDir() && m&0111 != 0 {
|
|
return nil
|
|
}
|
|
return fs.ErrPermission
|
|
}
|
|
|
|
func lookPath(name string, env []string) (string, error) {
|
|
// don't look if abs path provided
|
|
if filepath.Base(name) != name {
|
|
return name, nil
|
|
}
|
|
|
|
// don't look if exist in current dir
|
|
if err := findExecutable(name); err == nil {
|
|
return name, nil
|
|
}
|
|
|
|
path, err := findPath(env)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
for _, dir := range path {
|
|
if dir == "" {
|
|
dir = "."
|
|
}
|
|
p := filepath.Join(dir, name)
|
|
if err := findExecutable(p); err == nil {
|
|
return p, nil
|
|
}
|
|
}
|
|
return "", errNotFound
|
|
}
|
|
|
|
func findPath(env []string) ([]string, error) {
|
|
// find PATH=
|
|
const pathPrefix = "PATH="
|
|
for _, s := range env {
|
|
if strings.HasPrefix(s, pathPrefix) {
|
|
return filepath.SplitList(s[len(pathPrefix):]), nil
|
|
}
|
|
}
|
|
return nil, errNoPath
|
|
}
|