wide/util/os.go

100 lines
2.3 KiB
Go

// Copyright (c) 2014-2015, b3log.org
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package util
import (
"bytes"
"errors"
"os"
"os/exec"
"os/user"
"path/filepath"
"runtime"
"strings"
)
type myos struct{}
// OS utilities.
var OS = myos{}
// IsWindows determines whether current OS is Windows.
func (*myos) IsWindows() bool {
return "windows" == runtime.GOOS
}
// Pwd gets the path of current working directory.
func (*myos) Pwd() string {
file, _ := exec.LookPath(os.Args[0])
pwd, _ := filepath.Abs(file)
return filepath.Dir(pwd)
}
// Home returns the home directory for the executing user.
//
// This uses an OS-specific method for discovering the home directory.
// An error is returned if a home directory cannot be detected.
func (*myos) Home() (string, error) {
user, err := user.Current()
if nil == err {
return user.HomeDir, nil
}
// cross compile support
if OS.IsWindows() {
return homeWindows()
}
// Unix-like system, so just assume Unix
return homeUnix()
}
func homeUnix() (string, error) {
// First prefer the HOME environmental variable
if home := os.Getenv("HOME"); home != "" {
return home, nil
}
// If that fails, try the shell
var stdout bytes.Buffer
cmd := exec.Command("sh", "-c", "eval echo ~$USER")
cmd.Stdout = &stdout
if err := cmd.Run(); err != nil {
return "", err
}
result := strings.TrimSpace(stdout.String())
if result == "" {
return "", errors.New("blank output when reading home directory")
}
return result, nil
}
func homeWindows() (string, error) {
drive := os.Getenv("HOMEDRIVE")
path := os.Getenv("HOMEPATH")
home := drive + path
if drive == "" || path == "" {
home = os.Getenv("USERPROFILE")
}
if home == "" {
return "", errors.New("HOMEDRIVE, HOMEPATH, and USERPROFILE are blank")
}
return home, nil
}