#!/bin/sh
### BEGIN INIT INFO
# Provides:          kea-dhcp4-server
# Required-Start:    $local_fs $network $remote_fs $syslog
# Required-Stop:     $local_fs $network $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: Kea DHCP IPv4 Server
# Description:       Kea is an IPv4 and IPv6 DHCP server developed by Internet
#                    Systems Consortium providing a very high-performance with
#                    PostgreSQL, MySQL and memfile backends.
### END INIT INFO
# Author: Adam Majer <adamm@zombino.com>
# Do NOT "set -e"

# PATH should only include /usr/* if it runs after the mountnfs.sh script
PATH=/sbin:/usr/sbin:/bin:/usr/bin
DESC="kea-dhcp4"
NAME=kea-dhcp4-server
DAEMON=/usr/sbin/kea-dhcp4
DAEMON_ARGS="-c /etc/kea/kea-dhcp4.conf"
DAEMONUSER=_kea
PIDFILE=/run/kea/kea-dhcp4.kea-dhcp4.pid # depends on config-filename: https://kea.readthedocs.io/en/latest/arm/dhcp4-srv.html
SCRIPTNAME=/etc/init.d/$NAME
KEA_PIDFILE_DIR=/run/kea
KEA_LOCKFILE_DIR=/run/lock/kea

# Exit if the package is not installed
[ -x "$DAEMON" ] || exit 0

# Read configuration variable file if it is present
[ -r /etc/default/$NAME ] && . /etc/default/$NAME

# Load the VERBOSE setting and other rcS variables
. /lib/init/vars.sh

# Define LSB log_* functions.
# Depend on lsb-base (>= 3.2-14) to ensure that this file is present
# and status_of_proc is working.
. /lib/lsb/init-functions

create_lockfile_dir()
{
	if [ ! -d "$KEA_LOCKFILE_DIR" ]; then
		mkdir -m 0750 -p "$KEA_LOCKFILE_DIR"
		chown "$DAEMONUSER:" "$KEA_LOCKFILE_DIR"
	fi
}

create_pidfile_dir()
{
	if [ ! -d "$KEA_PIDFILE_DIR" ]; then
		mkdir -m 0750 -p "$KEA_PIDFILE_DIR"
		chown "$DAEMONUSER:" "$KEA_PIDFILE_DIR"
	fi
}

setcap_binary()
{
	setcap "cap_net_bind_service,cap_net_raw=+ep" $DAEMON
}

#
# Function that starts the daemon/service
#
do_start()
{
	create_lockfile_dir
	create_pidfile_dir
	setcap_binary
	export KEA_LOCKFILE_DIR
	# Return
	#   0 if daemon has been started
	#   1 if daemon was already running
	#   2 if daemon could not be started
	start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON --test > /dev/null \
		|| return 1
	start-stop-daemon --start --quiet --pidfile $PIDFILE --exec $DAEMON -b -c $DAEMONUSER -- \
		$DAEMON_ARGS \
		|| return 2
}

#
# Function that stops the daemon/service
#
do_stop()
{
	# Return
	#   0 if daemon has been stopped
	#   1 if daemon was already stopped
	#   2 if daemon could not be stopped
	#   other if a failure occurred
	start-stop-daemon --stop --quiet --retry=TERM/30/KILL/5 --pidfile $PIDFILE --exec $DAEMON --user $DAEMONUSER
	RETVAL="$?"
	[ "$RETVAL" = 2 ] && return 2
	# Wait for children to finish too if this is a daemon that forks
	# and if the daemon is only ever run from this initscript.
	# If the above conditions are not satisfied then add some other code
	# that waits for the process to drop all resources that could be
	# needed by services started subsequently.  A last resort is to
	# sleep for some time.
	start-stop-daemon --stop --quiet --oknodo --retry=0/30/KILL/5 --exec $DAEMON --user $DAEMONUSER
	[ "$?" = 2 ] && return 2
	# Many daemons don't delete their pidfiles when they exit.
	rm -f $PIDFILE
	return "$RETVAL"
}

#
# Function that sends a SIGHUP to the daemon/service
#
do_reload() {
	start-stop-daemon --stop --signal 1 --quiet --pidfile $PIDFILE --exec $DAEMON --user $DAEMONUSER
	return 0
}

case "$1" in
  start)
	[ "$VERBOSE" != no ] && log_daemon_msg "Starting $DESC" "$NAME"
	do_start
	case "$?" in
		0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
		2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
	esac
	;;
  stop)
	[ "$VERBOSE" != no ] && log_daemon_msg "Stopping $DESC" "$NAME"
	do_stop
	case "$?" in
		0|1) [ "$VERBOSE" != no ] && log_end_msg 0 ;;
		2) [ "$VERBOSE" != no ] && log_end_msg 1 ;;
	esac
	;;
  status)
	status_of_proc "$DAEMON" "$NAME" && exit 0 || exit $?
	;;
  reload|force-reload)
	log_daemon_msg "Reloading $DESC" "$NAME"
	do_reload
	log_end_msg $?
	;;
  restart)
	log_daemon_msg "Restarting $DESC" "$NAME"
	do_stop
	case "$?" in
	  0|1)
		do_start
		case "$?" in
			0) log_end_msg 0 ;;
			1) log_end_msg 1 ;; # Old process is still running
			*) log_end_msg 1 ;; # Failed to start
		esac
		;;
	  *)
		# Failed to stop
		log_end_msg 1
		;;
	esac
	;;
  *)
	#echo "Usage: $SCRIPTNAME {start|stop|restart|reload|force-reload}" >&2
	echo "Usage: $SCRIPTNAME {start|stop|status|restart|force-reload}" >&2
	exit 3
	;;
esac

: