#!/bin/sh
#
# Control script for squid cache manager operation
# Written by Andrei Boros, 03/22/2001
# E-mail : andrixnet@yahoo.com
# Greetings to Marc Slemko, whose apachectl inspired this script
#
# Released under the GNU General Public License version 2
# See http://www.gnu.org/copyleft for details
#
#	Errors levels returned by this script :
#	0  - success
#	1  - 
# 	2  - usage error
#	3  - squid not started, already running
#	4  - squid not stopped, not running
#	5  - squid could not be stopped
#	6  - squid could not be started
#	10 - reload attempt, but squid is not running
#	11 - parsing configuration but squid is not running 
#	12 - failed to reconfigure squid. try a parse first.
#
#
# Normally squid is reconfigured on the fly. I found no reason to 
# include a restart option
#
###########################################################################
#
#
# squid pid file
SQUID_PID=/var/log/squid/squid.pid
#
# squid binary
SQUID=/usr/local/squid/bin/squid
#
# squid configuration file.
SQUIDCONF=/usr/local/squid/etc/squid.conf
#
# 
# squid defines a shutdown timeout to wait for sockets to close. For a clean 
# shutdown of the cache, we will issue a shutdown command then wait this many
# seconds + 1 for this to complete. 
# A kill by rc.6 often leaves the PID file and squid won't start at next boot.
HOWLONG=`cat $SQUIDCONF | grep "shutdown_lifetime" | cut -f 2 -d " "`
HOWLONG2=`expr $HOWLONG + 2`
#
#
ERROR=0
ARGV="$@"
#
# No parameters ?
#
if [ "x$ARGV" = "x" ]; then
    ARGS="help"
fi
        
for ARG in $@ $ARGS
do
    # check for pid file
    if [ -f $SQUID_PID ]; then # PID file exists
	PID=`cat $SQUID_PID`
	if [ "x$PID" != "x" ]; then # PID exists
	    if kill -0 $PID 2>/dev/null ; then # a process using PID is running
		if ps -p $PID -o args | grep squid > /dev/null 2>&1; then 
		# that process is squid itself, OK
		    STATUS="squid (pid $PID) running"
		    RUNNING=1
		else    
		# squid not running, stale PID file contains PID of another
		# running process. No squid, remove the PID file
		    rm -f $SQUID_PID
    		    STATUS="squid (stale pid file removed) not running"
		    RUNNING=0
		fi    
	    else
	    # nothing using this PID. Remove file
		rm -f $SQUID_PID
		STATUS="squid (stale pid file removed) not running"
		RUNNING=0		 	
	    fi
	else
	# PID file is empty. Squid not running, remove file.
	    rm -f $SQUID_PID
	    STATUS="squid (stale pid file removed) not running"
	    RUNNING=0
	fi	
    else 
    # No PID file, not running.
        STATUS="squid (no pid) not running"
        RUNNING=0
    fi
	
    case $ARG in
    parse)
	if [ $RUNNING -eq 0 ]; then
	    echo "$0 $ARG: squid (pid $PID) not running"
	    ERROR=11
	    continue
	fi
#
# Parse squid configuration. Errors are allowed, it is the purpose of this command	
#    
	$SQUID -k parse  
	;;
    reload)
	if [ $RUNNING -eq 0 ]; then
	    echo "$0 $ARG: squid (pid $PID) not running"
	    ERROR=10
	    continue
	fi
	if $SQUID -k reconfigure ; then
	    echo "$0 $ARG: squid (pid $PID) reconfigured"
	else
	    echo "$0 $ARG: unable to reconfigure squid (pid $PID)"
	    ERROR=12	
	fi	    	
	;;
    stop)
        if [ $RUNNING -eq 0 ]; then
	    echo "$0 $ARG: $STATUS"
	    ERROR=4
	    continue
	fi
#
# Don't know why a simple kill doesn't always work. PID file and other things 
# remain and squid will refuse to start.
# 
# This is the proper way to stop squid. Put this in your shutdown scripts
#	    
	if $SQUID -k shutdown ; then
	    echo "Squid is shutting down. Waiting $HOWLONG2 seconds for cleanup..."
	    sleep $HOWLONG2 s
	    #
	    # Is squid PID file still present ? (It shouldn't)
	    #
	    if [ -f $SQUID_PID ]; then
	        echo "$0 $ARG: failed to stop squid (pid $PID)"
		ERROR=5
		continue
	    else	     
	        echo "$0 $ARG: squid (pid $PID) stopped"
	    fi	
	else 
	    echo "$0 $ARG: failed to shutdown squid (pid $PID)"
	    ERROR=5
	    continue
	fi	 	
	;;
    start)
        if [ $RUNNING -eq 1 ]; then
    	    echo "$0 $ARG: squid (pid $PID) already running"
	    ERROR=3
	    continue
	fi
	if $SQUID ; then
	     echo "$0 $ARG: squid started"
	else
	    echo "$0 $ARG: starting squid failed"
	    ERROR=6
	fi
	;;
    status)
        echo $STATUS
        continue
        ;;
    help)
        echo "usage: $0 (start|stop|reload|parse|status|help)"
        cat <<EOF
	    
start	- start squid
stop	- stop squid
reload	- reload squid configuration
parse	- test squid configuration file
status	- is squid running?
help	- this help message

EOF
        ERROR=2
        ;;
    *)
        echo "usage: $0 (start|stop|reload|parse|status|help)"
        echo "say $0 help for a command summary"
        ERROR=2
    esac
done

exit $ERROR