Shell Programming and Scripting

Programname=$(basename $0)  # While scheduling to cron, program name is needed.

Usage="Usage: $Programname [-a mtDelete/mtBackup] [-l/-L Backuplocation] [-t now/cron/hh:mm]"

IsCronJob=1     # default, script will run at now.
isBackUp=0	# default, it will take back up.
lFlag=0		# it is optional. default value is zero
LFlag=0		# it is optional. dfault value is zero
ERR=1
 
LOGDIR="$INTAS_INSTALL_DIR/envsw/logs"
BackupLocation="$INTAS_INSTALL_DIR/mt_backup"

mtlogFile="/tmp/mtclean.log.$$"

if [[ $# -lt 1 ]];
then
	echo "$Usage"
	return $ERR
fi

if [[ ! -d $BackupLocation ]];
then
	mkdir -p $BackupLocation 2>/dev/null
fi

while  getopts a:l:L:t: optvar
do
	case $optvar in
	a) action="$OPTARG"
		if [[ $action = "mtBackup" ]];
		then
			isBackUp=1
		fi
		;;
	l) BackupLocation="$OPTARG"
		if [[ $lFlag -eq 1 ]]; then
			echo "Either option l or L should be given to $Programname"
			echo "$Usage"
			echo "$Programname is terminated"
			return $ERR;
		fi
		if [[ $isBackUp -eq 1 ]];
		then	
			givenPath="$BackupLocation"
			if [[ ! -d $BackupLocation ]];
			then
				echo "Non-existant directory specified"
				
				mkdir -p $BackupLocation >/dev/null 2>&1
	                        if [[ $? = 0 ]];
        	                then
					echo "$Prograname creates the dirctory $BackupLocation"
				else
					echo "$Programname could not able to create the directory $BackupLocation"
					return $ERR
				fi
			else
				echo "Backup directory already exists"
			fi
			lFlag=1
			Llcron=l
		else
			echo "$Programname is executed with -l option without action mtBackup"
			echo "$Usage"
			echo "$Programname is terminated"
			return $ERR
		fi
		;;
	L) BackupLocation="$OPTARG"
		if [[ $LFlag -eq 1 ]]; then
			echo "Either option l or L should be given to $Programname"
			echo "$Usage"
			echo "$Programname is terminated"
			return $ERR;
		fi
		if [[ $isBackUp -eq 1 ]];
		then
		        givenPath="$BackupLocation"
			BackupLocation=$BackupLocation/backup$(date +%w)
			if [[ ! -d $BackupLocation ]];
			then
				echo "Non-existant directory $BackupLocation"
				mkdir -p $BackupLocation >/dev/null 2>&1
	                        if [[ $? = 0 ]];
        	                then
					echo "$Prograname creates the dirctory $BackupLocation"
				else
					echo "$Programname could not able to create the directory $BackupLocation"
					return $ERR
				fi
			else
				echo "Backup directory $BackupLocation is already exists"
			fi
			lFlag=1
			Llcron=L
		else
			echo "$Programname is executed with -L option without action mtBackup"
			echo "$Programname is terminating"
			return $ERR;
		fi
		;;
	t) WhentoRun="$OPTARG"
		#echo "$WhentoRun"
		if [[ $WhentoRun = "cron" ]];
		then
			IsCronJob=1
			echo "$Programname is running from cron"
		elif [[ $WhentoRun = "now" ]];
		then
			IsCronJob=1
			echo "$Programname starts Now"
		else
			if /bin/echo $WhentoRun | egrep '^[0-9]{1,2}:[0-5][0-9]$' >/dev/null; then
	                	echo "$Programname is scheduled to $WhentoRun at cron"
				hour=$(/bin/echo $WhentoRun | cut -d: -f1)
				minute=$(/bin/echo $WhentoRun | cut -d: -f2)
				IsCronJob=0
			else
                        	echo "Incorrect time format, time must be in HH:MM format"
                        	return $ERR
                	fi
		
		fi
		;;
	*) echo $Usage
	   return $ERR 
	  	;;
	esac
done

if [[ ! -w $BackupLocation ]];
then
	echo "$BackupLocation is not writable"
	return $ERR;
fi

if whence $Programname >/dev/null; then
        : We found this program in the path
else
        echo "Unable to locate $Progname in the PATH, check the .kshrc for correctness"
	return $ERR
fi

cd $LOGDIR
if [[ $? != 0 ]]; 
then
        echo "Unable to cd to $INTAS_INSTALL_DIR/envsw, exiting..."
	return $ERR
fi

if [[ ! -d $LOGDIR && -w $LOGDIR ]];
then
	echo "$LOGDIR directory does not exist or not writable."
	echo "Please check the user permission"
	return $ERR
fi


# If mtclean is exceuted from cron or with option now, we can skip below scheduling part.
if [[ $IsCronJob -eq 0 ]]; 
then
        if (crontab -l 2>&1 1>/dev/null | grep 'not authorized'); 
	then
                echo "Unable to use cron, contact your system administrator"
                echo "Check that $(whoami) has an entry in cron.allow"
                return $ERR;
 	else
		cronfile="crontab"	
		cronfile="$INTAS_INSTALL_DIR/envs/tmp/cur_crontab$$"
	        crontab -l 2>&1 | grep -v '^crontab' >$cronfile
        	if grep "$Programname .* cron .*" $cronfile >/dev/null; then
                	tmpvar=$(grep -v "$Progname .* cron .*" $cronfile)
                	echo "$tmpvar" >$cronfile
        	fi

		#echo "Cron: $cronfile"
		echo "$minute $hour" '* * *' ". ~/.kshrc; $(whence $Programname) -a $action -$Llcron $givenPath -t cron >>$mtlogFile" >> $cronfile
        fi
	crontab $cronfile >/dev/null 2>&1
        if crontab -l | diff - $cronfile >/dev/null; then
                if [[ $WhenToRun != 24:00 ]]; then
                        echo crontab has been installed correctly
                else
			echo "Error in crontab entry"
		fi
	else
		echo "Error in installing crontab"
	fi
else
	curmonth=$(date +%b)
	curdate=$(echo "$(date +%c)" | cut -d' ' -f3)

	if [[ $curdate = "" || $curdate = " " ]];
	then
		curdate=$(echo "$(date +%c)" | cut -d' ' -f4)
		today="$curmonth  $curdate"
	else
		today="$curmonth $curdate"
			
	fi

	FileList=$(find . -type f -name "*")	# List all the files.
	
	echo "Starting moving/removing files from $LOGDIR"
        extrafiles1=$(ls mt.*.*.*.* 2>/dev/null) 
	extrafiles2=$(ls *core* 2>/dev/null)
	for file in $FileList
	do
		if [[ $(ls -l $file 2>/dev/null) = *$today* ]]; 
		then
			echo "Skips $file file. It is today's file"
			cp $file $BackupLocation 2>/dev/null
			cat /dev/null >$file
			continue
					        
		fi
	        
		if [[ $isBackUp -eq 1 ]];
		then
			mv $file $BackupLocation 2>/dev/null
			
		else
			rm $file $BackupLocation 2>/dev/null
                        
		fi
	done

case $optvar in 
a)...
l|L)
  if [ flag is L ] ; then
    BackupLocation=$BackupLocation/backup$(date +%w)
  endif
t)...

webmut2@france>mt_clean -a mtDelete
Either option l or L should be given to mt_clean
Usage: mt_clean [-a mtDelete/mtBackup] [-l/-L Backuplocation] [-t now/cron/hh:mm]
mt_clean is terminated