Taken from https://raw.githubusercontent.com/CRAZY-VPN/SQUID3/master/squid3

squid3

#! /bin/sh
#-----------------------------
# squid	open source by crazy.
#-----------------------------

NAME=squid3
DESC="Squid HTTP Proxy"
DAEMON=/usr/sbin/squid3
PIDFILE=/var/run/$NAME.pid
CONFIG=/etc/squid3/squid.conf
SQUID_ARGS="-YC -f $CONFIG"

[ ! -f /etc/default/squid ] || . /etc/default/squid

. /lib/lsb/init-functions

PATH=/bin:/usr/bin:/sbin:/usr/sbin

[ -x $DAEMON ] || exit 0

ulimit -n 65535

find_cache_dir () {
	w=" 	"
        res=`$DAEMON -k parse -f $CONFIG 2>&1 |
		grep "Processing:" |
		sed s/.*Processing:\ // |
		sed -ne '
			s/^['"$w"']*'$1'['"$w"']\+[^'"$w"']\+['"$w"']\+\([^'"$w"']\+\).*$/\1/p;
			t end;
			d;
			:end q'`
        [ -n "$res" ] || res=$2
        echo "$res"
}

grepconf () {
	w=" 	"
        res=`$DAEMON -k parse -f $CONFIG 2>&1 |
		grep "Processing:" |
		sed s/.*Processing:\ // |
		sed -ne '
			s/^['"$w"']*'$1'['"$w"']\+\([^'"$w"']\+\).*$/\1/p;
			t end;
			d;
			:end q'`
	[ -n "$res" ] || res=$2
	echo "$res"
}

create_run_dir () {
	run_dir=/var/run/squid3
	usr=`grepconf cache_effective_user proxy`
	grp=`grepconf cache_effective_group proxy`

	if [ "$(dpkg-statoverride --list $run_dir)" = "" ] &&
	   [ ! -e $run_dir ] ; then
		mkdir -p $run_dir
	  	chown $usr:$grp $run_dir
		[ -x /sbin/restorecon ] && restorecon $run_dir
	fi
}

start () {
	cache_dir=`find_cache_dir cache_dir`
	cache_type=`grepconf cache_dir`
	run_dir=/var/run/squid3
	create_run_dir

	if test -d "$cache_dir" -a ! -d "$cache_dir/00"
	then
		log_warning_msg "Creating $DESC cache structure"
		$DAEMON -z -f $CONFIG
		[ -x /sbin/restorecon ] && restorecon -R $cache_dir
	fi

	umask 027
	ulimit -n 65535
	cd $run_dir
	start-stop-daemon --quiet --start \
		--pidfile $PIDFILE \
		--exec $DAEMON -- $SQUID_ARGS < /dev/null
	return $?
}

stop () {
	PID=`cat $PIDFILE 2>/dev/null`
	start-stop-daemon --stop --quiet --pidfile $PIDFILE --exec $DAEMON
	sleep 2
	if test -n "$PID" && kill -0 $PID 2>/dev/null
	then
		log_action_begin_msg " Waiting"
		cnt=0
		while kill -0 $PID 2>/dev/null
		do
			cnt=`expr $cnt + 1`
			if [ $cnt -gt 24 ]
			then
				log_action_end_msg 1
				return 1
			fi
			sleep 5
			log_action_cont_msg ""
		done
		log_action_end_msg 0
		return 0
	else
		return 0
	fi
}

cfg_pidfile=`grepconf pid_filename`
if test "${cfg_pidfile:-none}" != "none" -a "$cfg_pidfile" != "$PIDFILE"
then
	log_warning_msg "squid.conf pid_filename overrides init script"
	PIDFILE="$cfg_pidfile"
fi

case "$1" in
    start)
	res=`$DAEMON -k parse -f $CONFIG 2>&1 | grep -o "FATAL: .*"`
	if test -n "$res";
	then
		log_failure_msg "$res"
		exit 3
	else
		log_daemon_msg "Starting $DESC" "$NAME"
		if start ; then
			log_end_msg $?
		else
			log_end_msg $?
		fi
	fi
	;;
    stop)
	log_daemon_msg "Stopping $DESC" "$NAME"
	if stop ; then
		log_end_msg $?
	else
		log_end_msg $?
	fi
	;;
    reload|force-reload)
	res=`$DAEMON -k parse -f $CONFIG 2>&1 | grep -o "FATAL: .*"`
	if test -n "$res";
	then
		log_failure_msg "$res"
		exit 3
	else
		log_action_msg "Reloading $DESC configuration files"
	  	start-stop-daemon --stop --signal 1 \
			--pidfile $PIDFILE --quiet --exec $DAEMON
		log_action_end_msg 0
	fi
	;;
    restart)
	res=`$DAEMON -k parse -f $CONFIG 2>&1 | grep -o "FATAL: .*"`
	if test -n "$res";
	then
		log_failure_msg "$res"
		exit 3
	else
		log_daemon_msg "Restarting $DESC" "$NAME"
		stop
		if start ; then
			log_end_msg $?
		else
			log_end_msg $?
		fi
	fi
	;;
    status)
	status_of_proc -p $PIDFILE $DAEMON $NAME && exit 0 || exit 3
	;;
    *)
	echo "Utilize: /etc/init.d/$NAME {start|stop|reload|force-reload|restart|status}"
	exit 3
	;;
esac

exit 0