blob: 7b56afa85664fc40ad76e38ae09fd7258db9843e [file] [log] [blame]
// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package exec
import (
"os"
"strings"
)
func chkStat(file string) bool {
d, err := os.Stat(file)
if err != nil {
return false
}
return d.IsRegular()
}
func canExec(file string, exts []string) (string, bool) {
if len(exts) == 0 {
return file, chkStat(file)
}
f := strings.ToLower(file)
for _, e := range exts {
if strings.HasSuffix(f, e) {
return file, chkStat(file)
}
}
for _, e := range exts {
if f := file + e; chkStat(f) {
return f, true
}
}
return ``, false
}
func LookPath(file string) (string, os.Error) {
exts := []string{}
if x := os.Getenv(`PATHEXT`); x != `` {
exts = strings.Split(strings.ToLower(x), `;`, -1)
for i, e := range exts {
if e == `` || e[0] != '.' {
exts[i] = `.` + e
}
}
}
if strings.Contains(file, `\`) || strings.Contains(file, `/`) {
if f, ok := canExec(file, exts); ok {
return f, nil
}
return ``, &os.PathError{"lookpath", file, os.ENOENT}
}
if pathenv := os.Getenv(`PATH`); pathenv == `` {
if f, ok := canExec(`.\`+file, exts); ok {
return f, nil
}
} else {
for _, dir := range strings.Split(pathenv, `;`, -1) {
if f, ok := canExec(dir+`\`+file, exts); ok {
return f, nil
}
}
}
return ``, &os.PathError{"lookpath", file, os.ENOENT}
}