// -*- Mode: Go; indent-tabs-mode: t -*-

/*
 * Copyright (C) 2014-2015 Canonical Ltd
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 3 as
 * published by the Free Software Foundation.
 *
 * 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/>.
 *
 */

package osutil

import (
	"os/exec"
	"syscall"
)

// ExitCode extract the exit code from the error of a failed cmd.Run() or the
// original error if its not a exec.ExitError
func ExitCode(runErr error) (e int, err error) {
	// TODO: with golang-1.12 this becomes a bit nicer:
	//       https://github.com/golang/go/issues/26539
	// golang, you are kidding me, right?
	if exitErr, ok := runErr.(*exec.ExitError); ok {
		waitStatus := exitErr.Sys().(syscall.WaitStatus)
		e = waitStatus.ExitStatus()
		return e, nil
	}
	return e, runErr
}