swap

#!/bin/bash
## show swap used by each process

function getswap {
    SORTED=$1
    REVERSE=$2
    GREP_OPTARG=$3

    SUM=0
    OVERALL=0
    STATISTICS=""
    for DIR in `find /proc/ -maxdepth 1 -type d | egrep "^/proc/[0-9]"` ; do
        PID=`echo $DIR | cut -d / -f 3`
        PROGNAME=`ps -p $PID -o comm --no-headers`
        if [ "$GREP_OPTARG"x != ""x ]; then
            PROGNAME=`echo $PROGNAME | grep -e $GREP_OPTARG`
            if [ "$PROGNAME"x == ""x ]; then
                continue      
            fi 
        fi
        
        for SWAP in `grep Swap $DIR/smaps 2>/dev/null| awk '{ print $2 }'` 
        do
            let SUM=$SUM+$SWAP
        done

        if [ $SUM != 0 ] ; then
            if [ $SORTED == true ] ; then
                STATISTICS=$STATISTICS+"PID=$PID - Swap used: $SUM k - ($PROGNAME )\n"
            else
                echo "PID=$PID - Swap used: $SUM k - ($PROGNAME )"
            fi
        fi

        let OVERALL=$OVERALL+$SUM
        SUM=0
    done

    if [ $SORTED == true ]; then
        if [ $REVERSE == true ]; then
            echo -e $STATISTICS | sort -nk 5 -r 
        else 
            echo -e $STATISTICS | sort -nk 5 
        fi
    fi

    echo "Overall swap used: $OVERALL k"
}

SORTED=false
REVERSE=false
GREP_OPTARG=""

while getopts "hsrg:" arg
do
    case $arg in 
            s)
               SORTED=true
               ;;
            r)
               REVERSE=true
               ;;
            g)
               GREP_OPTARG=$OPTARG 
               ;;
            h)
               echo -e "Usage: sudo swap [-s[-r]] [-g GREP_ARG] 
-s sorted by swap used 
-r sorted reverse 
-g find specified process by 'grep' command 
                       "
               exit 0
              ;;
            ?)  
               echo -e "Usage: sudo swap [-s[-r]] [-g GREP_ARG] 
                               
-s sorted by swap used 
-r sorted reverse 
-g find specified process by 'grep' command 
                       "
               exit 1 ;;
    esac
done   

if [ ! -d "/proc" ]; then
    echo "cannot read infomation from /proc, exit!"
    exit 1
fi
getswap $SORTED $REVERSE $GREP_OPTARG