#!/bin/bash

# Status:  Requires su password.  Should rewrite to do sudo instead.
#          Also, other errors.  Needs cleanup.
# --Fred 11/26/2012

function usage() {
    bn=`basename $0`
    echo -e "usage: $bn -u <user> -t <email@visibiz.com> -o -p .7"
    echo -e "Options: -u User, -t email to this address, -o suppress output, -p percentage of max files to allow before alerts go out"
}

to=root
#Default to 70 percent
thresholdPercent=.7
# Ensure we have some params, if not exit
if [ ! $# -gt 0 ]; then
    usage
    exit 1
fi

# -----------------------------------------------------------------------------------#
# Set variables for commandline argument values
# -----------------------------------------------------------------------------------#
while getopts "u:t:p:o" opt; do
  case $opt in
      u)
        user=$OPTARG
        ;;
      o)
        output=1
        ;;
      t)
        to=$OPTARG
        ;;
      p)
        thresholdPercent=$OPTARG
        ;;
      :)
        log "Option -$OPTARG requires an argument." >&2
        exit 1
      ;;
  esac
done

# get this users max files
maxfiles=$(su - $user -c "ulimit -a | grep 'open files'" | awk -F '  *' '{print $4}')

#ensure we were able to get something here
if [ $? -ne 0 ]; then
    echo "Error occurred when SU - $user"
    exit 1
fi

# get the number of current files open
openfiles=$(/usr/sbin/lsof | grep "$user" | wc -l)
threshold=$(echo "scale=10; $maxfiles*$thresholdPercent" | bc | awk '{printf "%.0f\n", $1}')

# Echo some output if not supressing
if [[ ! $output ]]; then
    echo -e "USER  \t\t\t\tMaxFiles  \t\t\tOpenFiles  \t\t\tUserThreshold"
    echo -e "${user} \t\t\t${maxfiles}  \t\t\t\t${openfiles} \t\t\t\t${threshold}"
fi

# Compare open files to threshold, if low send email 
if [ $openfiles -gt $threshold ]; then
   echo "File handles low..."
   echo -e "$HOSTNAME file handles low for $user \n\n openfiles: $openfiles, alert threshold: $threshold, maxfiles: $maxfiles" | mail -s "File handles low on $user@$HOSTNAME" -r "filelow@$HOSTNAME.visibiz.com" ${to}
fi

exit 0