#!/bin/sh
# /etc/rc.d/rc.ntpd

# Start, stop, and restart the Network Time Protocol daemon.
# Modified to test online status, ntp.conf readability, existance
# of already running process, ntpdate success, and restoring clock to local time.

# Normal expectation when running ntpd from an rc.d script is that a box is
# always connected (broadband). This is not the case for dialup users. Dialup
# users might want to enable this script in rc.d, but should have some
# feedback to understand why the script failed --- they are not yet online.

# modified for colorized screen messages and local needs
source /etc/functions-colors

#initialize variables and locations
NTPDATE=/usr/sbin/ntpdate
NTPDAEMON=/usr/sbin/ntpd
NTPCONFIGFILE=/etc/ntp.conf
NTPLOG=/var/log/ntp/ntp.log
NTPPID=/var/run/ntpd.pid

# insert two appropriate regional servers here
# find public servers at http://ntp.isc.org/bin/view/Servers/StratumTwoTimeServers
# NTPSERVERS="ntp1.cs.wisc.edu ntp3.cs.wisc.edu"
# or use the ntp system pool servers
# note: always use pool servers to run ntpd (see /etc/ntp.conf), but know
# that using them in this particular script will cause a second or two delay
NTPSERVERS="2.us.pool.ntp.org 3.us.pool.ntp.org"

Exit_Script ()
{
if [ "$1" = "" ] ; then
  echo -e "${BOLDYELLOW}Exiting this script.${COLOR_RESET}"
else
  echo -e "${BOLDYELLOW}Exiting the ${BOLDGREEN}$1${BOLDYELLOW} script.${COLOR_RESET}"
fi
echo
exit 1
}

Ping_Test ()
{
# test online status before trying to run ntp daemon
TESTURL="`echo $NTPSERVERS | awk '{print $1}'`"
GOODPINGTEST="Ping test to ${BOLDGREEN}$TESTURL${COLOR_RESET} is okay."
BADPINGTEST="Ping test to ${BOLDGREEN}$TESTURL${COLOR_RESET} failed."

echo -e "${BOLDWHITE}Testing online status by pinging ${BOLDGREEN}$TESTURL${COLOR_RESET}."
# Any test longer than two seconds probably is a DNS lookup problem.
TIMEMARKER1=`date +%s`
# ping once and wait one second
ping -c 2 -W 2 $TESTURL &> /dev/null
PINGERROR=`echo $?`
TIMEMARKER2=`date +%s`
if [ $(($TIMEMARKER2-$TIMEMARKER1)) -gt 2 ] ; then
  # let's quit right now
  echo "Response time was $(($TIMEMARKER2-$TIMEMARKER1)) seconds."
  echo "The delay time probably was caused by the DNS lookup."
  echo -e "You probably are not online or the IP address"
  echo -e "  for ${BOLDGREEN}$TESTURL${COLOR_RESET} is not in the /etc/hosts file."
  echo -e $BADPINGTEST
  PINGTEST="FAILED"
  echo
else
  echo -e "IP address for ${BOLDGREEN}$TESTURL${COLOR_RESET} found."
  #echo "IP address is either in the /etc/hosts file or you have access to a DNS server."
  #echo
  if [ "$PINGERROR" = "0" ] ; then
    echo -e $GOODPINGTEST
    PINGTEST="PASSED"
  else
    # no response, so try again but with more patience
    echo -e $BADPINGTEST
    echo
    echo -e "${BOLDYELLOW}No initial response--trying again.${COLOR_RESET}"
    ping -c 3 -W 3 $TESTURL
    PINGERROR=`echo $?`
    if [ "$PINGERROR" = "0" ] ; then
      echo -e $GOODPINGTEST
      PINGTEST="PASSED"
    else
      echo -e $BADPINGTEST
      PINGTEST="FAILED"
      echo
    fi
  fi
fi
export PINGTEST
}

# Start ntpd:
ntpd_start() {
  # Tell the viewers what's going to happen.
  echo -e "${BOLDWHITE}Starting the network time protocol daemon:${COLOR_RESET}"
  echo " $NTPDAEMON"
  Ping_Test
  if [ "$PINGTEST" = "FAILED" ] ; then # not connected
    Exit_Script $0
  fi
	# verify the config file exists
	#echo
	echo -e "${BOLDWHITE}Looking for $NTPCONFIGFILE...${COLOR_RESET}"
	if [ -r $NTPCONFIGFILE ]; then
		echo -e "The config file ${BOLDGREEN}$NTPCONFIGFILE${COLOR_RESET} exists."
	else
		echo -e "${BOLDRED}The config file ${BOLDGREEN}$NTPCONFIGFILE${BOLDRED} is missing or unreadable.${COLOR_RESET}."
    Exit_Script $0
	fi
	# Is ntpd already running?
	#echo
	echo -e "${BOLDWHITE}Looking for other instances of ntpd already running...${COLOR_RESET}"
	NTPD_PID=`/sbin/pidof ntpd`
	if [ "$NTPD_PID" = "" ]; then
		echo "The NTP daemon does not seem to be running."
	else
		echo "NTPD_PID = $NTPD_PID"
		echo -e "${BOLDRED}Warning: $NTPDAEMON is already running.${COLOR_RESET}."
    Exit_Script $0
	fi
	# first update the clock from a regional server to avoid gross drift errors
	echo -e "${BOLDWHITE}Setting clock from regional NTP servers...${COLOR_RESET}"
	$NTPDATE -suv $NTPSERVERS
	# did ntpdate succeed in connecting? If not then terminate.
	if [ "$?" = "0" ] ; then
		echo -e "${BOLDWHITE}$NTPDATE${COLOR_RESET} seems to have connected."
	else
		echo -e "${BOLDWHITE}$NTPDATE${BOLDRED} did not connect to the regional servers.${COLOR_RESET}."
    Exit_Script $0
	fi
	#now ready to start ntp daemon
	echo -e "Starting the network time protocol daemon."
	$NTPDAEMON -g -c $NTPCONFIGFILE -l $NTPLOG -p $NTPPID
}

# Stop ntpd:
ntpd_stop() {
	echo -e "${BOLDWHITE}Stopping the network time protocol daemon:${COLOR_RESET}"
	echo " $NTPDAEMON"
	# killall ntpd
  kill `cat $NTPPID`
  #echo
  sleep 1
  rm -f /var/run/ntpd.pid
  killall ntpd 2> /dev/null
}

# Restart ntpd:
ntpd_restart() {
	echo -e "${BOLDWHITE}Restarting the network time protocol daemon:${COLOR_RESET}"
	echo " $NTPDAEMON"
	ntpd_stop
	sleep 1
	ntpd_start
}

case "$1" in
'start')
  ntpd_start
  ;;
'stop')
  ntpd_stop
  ;;
'restart')
  ntpd_restart
  ;;
*)
 echo -e "${BOLDRED}Usage:${COLOR_RESET} $0 start|stop|restart"
 exit 1
esac