#!/bin/sh 
 
 # safe_clamd - a script to start clamd and restart if it dies unexpectedly
 # Please report bugs at https://wwws.clamav.net/bugzilla/show_bug.cgi?id=2026
 # Usage:
 # start with ./safe_clamd
 # stop by sending a TERM signal to the safe_clamd process
 
 {
 ####################### CONFIGURATION #######################
 # path to clamd.conf
 CLAMDCONF='/usr/local/etc/clamd.conf'
 # path to clamd binary
 CLAMDBIN='/usr/local/sbin/clamd'
 # interval between checks
 SLEEPINTERVAL=3
 # after a successful restart, sleep for $THROTTLE secs before attempting to restart clamd again
 THROTTLE=30
 ##################### END CONFIGURATION #####################
 
 # Do not touch anything below this line, unless you know what you are doing

 trap "signalClamd HUP" HUP
 trap "signalClamd TERM" TERM
 trap "signalClamd USR2" USR2

 
 getPid() {
 	PIDFILE=`grep ^PidFile $CLAMDCONF | sed -e 's/^PidFile\s*//'`

 	if [ -z "$PIDFILE" ]

 	then
 		# missing PidFile directive
 		echo "Please enable the PidFile directive in $CLAMDCONF. See man clamd.conf for more info."
 		exit 1
 	fi
 	CLAMDPID=`cat $PIDFILE 2>/dev/null | grep -Eo '^[0-9]+$'` 
 	if [ -z "$CLAMDPID" ]
 	then
 		# empty pidfile
 		CLAMDPID=0
 		return
 	fi
 	if ps p $CLAMDPID | grep -v grep | grep $CLAMDBIN > /dev/null
 	then 
 		# good pid
 		return
 	fi
 	# invalid pid
 	CLAMDPID=0
 }
 
 startClamd() {
 	rm -f $PIDFILE 
 	if test -f $PIDFILE
 	then 
 		echo "ERROR: cannot remove $PIDFILE" 
 		exit 1 
 	else
 		$CLAMDBIN $args
 		if [ $? -ne 0 ]
 		then
 			exit $?
 		fi
 		sleep $THROTTLE
 	fi 
 }
 
 signalClamd() {
 	getPid
 	if [ $CLAMDPID -gt 0 ]; then
 		echo "Sending $1 to pid $CLAMDPID..."
 		kill -$1 $CLAMDPID
 	else
 		echo "$CLAMDBIN is not running."
 	fi
 	if [ "$1" == "TERM" ]; then
 		echo Exiting $0 ...
 		exit
 	fi
 }
 
 args=$@
 
 # start clamd
 # if it start successfully, enter loop
 # every 5 secs, find pid, verify it belongs to clamd, kill -0 
 # restart it if dead
 while [ true ]; do
 	if test -r "$CLAMDCONF" 
 	then 
 		if test	-x "$CLAMDBIN"
 		then
 			# retrieve pid
 			getPid
 			# pid found?
 			if [ $CLAMDPID -gt 0 ]
 			then
 				if kill -0 $CLAMDPID > /dev/null 2>/dev/null
 	      			then 
 					# pid is alive, sleep before next check
 					sleep $SLEEPINTERVAL
 	    			else
 					# stale pid
 					rm -f $PIDFILE
 					startClamd
 	    			fi
 			else
 				# pid does not belong to clamd 
 				startClamd
 			fi 
 		else	
 			echo $CLAMDBIN not found
 			exit 1
 		fi 
 	else
 		echo $CLAMDCONF not found
 		exit 1
 	fi
 done
 
 } &