path: root/common/path.go

// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package common

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

// MakeName creates a node name that follows the ethereum convention
// for such names. It adds the operation system name and Go runtime version
// the name.
func MakeName(name, version string) string {
    return fmt.Sprintf("%s/v%s/%s/%s", name, version, runtime.GOOS, runtime.Version())
}

func ExpandHomePath(p string) (path string) {
    path = p
    sep := string(os.PathSeparator)

    // Check in case of paths like "/something/~/something/"
    if len(p) > 1 && p[:1+len(sep)] == "~"+sep {
        usr, _ := user.Current()
        dir := usr.HomeDir

        path = strings.Replace(p, "~", dir, 1)
    }

    return
}

func FileExist(filePath string) bool {
    _, err := os.Stat(filePath)
    if err != nil && os.IsNotExist(err) {
        return false
    }

    return true
}

func AbsolutePath(Datadir string, filename string) string {
    if filepath.IsAbs(filename) {
        return filename
    }
    return filepath.Join(Datadir, filename)
}

func HomeDir() string {
    if home := os.Getenv("HOME"); home != "" {
        return home
    }
    if usr, err := user.Current(); err == nil {
        return usr.HomeDir
    }
    return ""
}