#!/bin/sh
### BEGIN INIT INFO
# Provides:          ashd
# Required-Start:    $local_fs $remote_fs $network $syslog
# Required-Stop:     $local_fs $remote_fs $network $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: The ashd HTTP server
### END INIT INFO

set -e

. /lib/lsb/init-functions

PATH=/usr/local/bin:/usr/local/sbin:$PATH
HTPARSER="$(which htparser || true)"
PIDFILE=/var/run/ashd.pid
GRACE_PERIOD=10
USER=nobody
CHROOT=/var/tmp
PORTSPEC="plain"
ROOTSPEC="dirplex /srv/www"
[ -r /etc/default/locale ] && . /etc/default/locale
[ -r /etc/default/ashd ] && . /etc/default/ashd
[ -x "$HTPARSER" ] || exit 0

start() {
    export LANG
    [ -n "$SILENT_INIT" ] || log_daemon_msg "Starting HTTP server" "ashd"
    if start-stop-daemon -S -p "$PIDFILE" -qa "$HTPARSER" -- -Sf -p "$PIDFILE" -u "$USER" -r "$CHROOT" $PORTSPEC -- $ROOTSPEC; then
	[ -n "$SILENT_INIT" ] || log_success_msg
    else
	[ -n "$SILENT_INIT" ] || log_end_msg 1
    fi
}

kill_wholly() {
    start-stop-daemon -K -p "$PIDFILE" -qx "$HTPARSER"
}

kill_listen() {
    pid=$(cat "$PIDFILE" 2>/dev/null || true)
    if [ -z "$pid" ]; then
	log_failure_msg "no pid file"
	return 1
    fi
    if ! kill -0 "$pid"; then
	log_failure_msg "invalid saved pid"
	return 1
    fi
    [ -n "$SILENT_INIT" ] || log_progress_msg "listen"
    kill -TERM "$pid"
    for try in 0 1 2 3 4 5; do
	  sleep $try
	  case "$(wc -l <"$PIDFILE")" in
	      1) continue ;;
	      0|2) return 0 ;;
	      *)
		  log_failure_msg "could not parse pid file"
		  return 1
		  ;;
	  esac
    done
    log_failure_msg "htparser did not stop listening, killing it completely"
    kill_wholly
    start-stop-daemon -K -p "$PIDFILE" -qx "$HTPARSER"
    return 1
}

stop_listen() {
    [ -n "$SILENT_INIT" ] || log_daemon_msg "Stopping HTTP server" "ashd"
    if kill_listen; then
	[ -n "$SILENT_INIT" ] || log_success_msg
    else
	[ -n "$SILENT_INIT" ] || log_end_msg $?
    fi
}

stop_gracefully() {
    [ -n "$SILENT_INIT" ] || log_daemon_msg "Stopping HTTP server" "ashd"
    if ! kill_listen ; then
	log_end_msg 1
	return 1
    fi
    pid=$(cat "$PIDFILE" 2>/dev/null || true)
    if kill -0 "$pid" 2>/dev/null; then
	[ -n "$SILENT_INIT" ] || log_progress_msg "waiting for remaining connections..."
	for try in $(seq "$GRACE_PERIOD"); do
	    sleep 1
	    if ! kill -0 "$pid" 2>/dev/null; then
		[ -n "$SILENT_INIT" ] || log_success_msg
		return 0
	    fi
	done
    else
	[ -n "$SILENT_INIT" ] || log_success_msg
	return 0
    fi
    [ -n "$SILENT_INIT" ] || log_progress_msg "terminating remaining connections"
    if kill_wholly; then
	[ -n "$SILENT_INIT" ] || log_success_msg
    else
	log_end_msg 1
    fi
}

case "$1" in
    start)
	start
	;;
    stop)
	stop_gracefully
	;;
    restart)
	stop_listen
	# Truncate PID file to allow start-stop-daemon to work despite remaining connections.
	>"$PIDFILE"
	start
	;;
esac

exit 0