#!/bin/sh
#
# Plugin return codes
#
# OK = 0
# The plugin was able to check the service and it appeared to be
# functioning properly
#
# Warning = 1
# The plugin was able to check the service, but it appeared to be above
# some "warning" threshold or did not appear to be working properly
#
# Critical = 2
# The plugin detected that either the service was not running or it was
# above some "critical" threshold
#
# Unknown = 3
# Invalid command line arguments were supplied to the plugin or low-level
# failures internal to the plugin (such as unable to fork, or open a tcp
# socket) that prevent it from performing the specified operation.
# Higher-level errors (such as name resolution errors, socket timeouts, etc)
# are outside of the control of plugins and should generally NOT be reported
# as UNKNOWN states.

# default path
PATH=/sbin:/usr/sbin:/bin:/usr/bin:/usr/local/sbin:/usr/local/bin

ST_OK=0
ST_WR=1
ST_CR=2
ST_UN=3

# Plugin name
PROGNAME=`basename $0`

# Version
VERSION="Version 1.0"

# Author
AUTHOR="Majo Jamrich"


print_version() {
    echo "$PROGNAME $VERSION $1"
}

print_help() {
    print_version "($AUTHOR)"
    echo ""
    echo "$PROGNAME is a Nagios plugin to check CPU utilization."
    echo ""
    echo "Options:"
    echo ""
    echo "--warning | -w"
    echo "--critical | -c"
    echo "--help | --usage"
    echo ""
    echo "Usage:"
    echo "./check_cpu_usage -w 80 -c 100"
    echo ""
    exit $ST_UN
}

case "$1" in
    --help|-h|--usage|-u)
        print_help
        exit $ST_UN
        ;;
    --warning|-w)
        host=$2
        ;;
    --critical|-c)
        host=$2
        ;;
    -V)
        print_version
        exit
        ;;
    *)
        echo "Unknown argument: $1"
        echo "For more information please try -h or --help!"
        exit $ST_UN
        ;;
esac
shift

if [ `uname` != "FreeBSD" ]; then
    echo "This plugin is only for FreeBSD."
fi

if [ -z $1 ] || [ -z $3 ]; then
    print_help
    exit  $ST_UN
fi

if [ "$1" -ge "$3" ]; then
    echo "Warning value must be greater than critical value!"
    exit $ST_UN
fi

warn=$1
crit=$3

cpu_all=$( iostat -c 2 -t proc | tail -n 1 | awk '{print $3 " " $5 " " $7}' )
cpu_user=$( echo $cpu_all | awk '{print $1}')
cpu_sys=$(  echo $cpu_all | awk '{print $2}')
cpu_idle=$( echo $cpu_all | awk '{print $3}')
cpu_usage=$(( 100 - $cpu_idle )) 
perfdata="cpu_usage=$cpu_usage%;$warn;$crit; cpu_user=$cpu_user%; cpu_system=$cpu_sys%;"

if [ $( echo "$cpu_usage>$1" | bc ) -gt 0 ] && [ $( echo "$cpu_usage<$3" | bc ) -gt 0 ]; then
    echo "WARNING - CPU usage is $cpu_usage% for server `hostname`. |$perfdata"
    exit $ST_WR
elif [ $( echo "$cpu_usage>$3" | bc ) -gt 0 ]; then
    echo "CRITICAL - CPU usage is $cpu_usage% for server `hostname`. |$perfdata"
    exit $ST_CR
else
    echo "OK - CPU usage is $cpu_usage% for server `hostname`. |$perfdata"
    exit $ST_OK
fi