/*
goredo -- djb's redo implementation on pure Go
Copyright (C) 2020-2021 Sergey Matveev <stargrave@stargrave.org>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, version 3 of the License.

This program 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

// Temporary files

package main

import (
	"os"
	"path"
	"strconv"
	"time"
)

func tempsuffix() string {
	return strconv.FormatInt((time.Now().UnixNano()+int64(os.Getpid()))&0xFFFFFFFF, 16)
}

func tempfile(dir, prefix string) (*os.File, error) {
	// It respects umask, unlike ioutil.TempFile
	name := path.Join(dir, TmpPrefix+prefix+"."+tempsuffix())
	return os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_EXCL, os.FileMode(0666))
}