aptly/systemd/activation/files.go

54 lines
1.4 KiB
Go

// Copyright 2015 CoreOS, Inc.
//
// 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 activation implements primitives for systemd socket activation.
package activation
import (
"os"
"strconv"
"syscall"
)
// based on: https://gist.github.com/alberts/4640792
const (
listenFdsStart = 3
)
// Files returns all the fds passed from systemd
func Files(unsetEnv bool) []*os.File {
if unsetEnv {
defer os.Unsetenv("LISTEN_PID")
defer os.Unsetenv("LISTEN_FDS")
}
pid, err := strconv.Atoi(os.Getenv("LISTEN_PID"))
if err != nil || pid != os.Getpid() {
return nil
}
nfds, err := strconv.Atoi(os.Getenv("LISTEN_FDS"))
if err != nil || nfds == 0 {
return nil
}
files := make([]*os.File, 0, nfds)
for fd := listenFdsStart; fd < listenFdsStart+nfds; fd++ {
syscall.CloseOnExec(fd)
files = append(files, os.NewFile(uintptr(fd), "LISTEN_FD_"+strconv.Itoa(fd)))
}
return files
}