func main() {
var fg, bgChild bool
flag.BoolVar(&fg, "fg", false, "run in foreground")
flag.BoolVar(&bgChild, "bg-child", false, "")
var nfiles int = nfilesGet()
var nfilesReq int
flag.IntVar(&nfilesReq, "nfiles", nfiles, "maximum number of files")
flag.IntVar(&nfilesReq, "n", nfiles, "maximum number of files")
var port int = 20444
flag.IntVar(&port, "port", port, "listening port")
flag.IntVar(&port, "p", port, "listening port")
var user string
flag.StringVar(&user, "user", "", "run as user")
flag.StringVar(&user, "u", "", "run as user")
var watchDirectory string
flag.StringVar(&watchDirectory, "watch-directory", "", "directory to watch for updates")
flag.StringVar(&watchDirectory, "d", "", "directory to watch for updates")
flag.StringVar(&watchDirectory, "update-directory", "", "")
var pidFile string
flag.StringVar(&pidFile, "pid-file", "", "file to write process PID")
var logFile string
flag.StringVar(&logFile, "log", "", "log file")
flag.StringVar(&logFile, "log-file", "", "log file")
flag.Parse()
var logw io.Writer = ioutil.Discard
if logFile != "" {
logw, err := os.OpenFile(logFile, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0660)
if err != nil {
log.Fatal(err)
}
log.SetOutput(io.MultiWriter(logw, os.Stderr))
}
if nfiles != nfilesReq {
nfiles = nfilesSet(nfilesReq)
if nfiles < nfilesReq {
log.Printf("limited to %d open files\n", nfiles)
}
}
var listener net.Listener
var err error
if bgChild {
listener, err = net.FileListener(os.NewFile(3, "listen-fd"))
} else {
listener, err = net.Listen("tcp", fmt.Sprintf(":%d", port))
}
if err != nil {
log.Fatal(err)
}
if user != "" {
userSet(user)
}
if watchDirectory != "" && directoryWatcher == nil {
log.Fatalf("this platform does not support `--update-directory`")
} else if watchDirectory != "" {
go directoryWatcher(watchDirectory)
}
if pidFile != "" {
err := ioutil.WriteFile(pidFile, []byte(fmt.Sprintf("%d\n", os.Getpid())), 0660)
if err != nil {
log.Fatal(err)
}
}
if !fg && !bgChild {
tcpListenFd, err := listener.(*net.TCPListener).File()
if err != nil {
log.Fatal(err)
}
args := []string{"--bg-child"}
if logFile != "" {
args = append(args, "--log-file", logFile)
}
if pidFile != "" {
args = append(args, "--pid-file", pidFile)
}
if user != "" {
args = append(args, "--user", user)
}
if watchDirectory != "" {
args = append(args, "--watch-directory", watchDirectory)
}
cmd := exec.Command(os.Args[0], args...)
cmd.ExtraFiles = []*os.File{tcpListenFd}
if err = cmd.Start(); err != nil {
log.Fatal(err)
}
os.Exit(0)
}
if bgChild {
unix.Setpgid(0, 0)
signal.Ignore(unix.SIGHUP)
log.SetOutput(logw)
os.Stdin.Close()
os.Stdout.Close()
os.Stderr.Close()
}
http.HandleFunc("/poll", PollRequest)
http.HandleFunc("/update", UpdateRequest)
log.Fatal(http.Serve(listener, nil))
}
func BecomeProcessGroupLeader() {
if pid != pgid {
unix.Setpgid(0, 0)
}
}