#!/usr/bin/perl

# check_cmusage version 1.0, 17/7/2013
# Written by Caofaguo <Hunter_cao@163.com>

# This plugin is for LINUX edition. Computing cpu and mem usage. 
# You need basic perl package to run this plugin. 


use warnings;
use strict;
use Getopt::Std;

my $STATE_OK = 0;
my $STATE_WARNING = 1;
my $STATE_CRITICAL = 2;
my (@paraw,@parac,$cpu_w,$mem_w,$cpu_c,$mem_c);

my $USAGE = "
$0 <-w cpu,memory> <-c cpu,memory>

     -c # CPU,Memory Warning value;
     -w # CPU,Memory Critical value;
     For example: check_cmusage -w 90,90 -c 95,95
";

my %opts;
unless (getopts('c:w:', \%opts)) {
   print $USAGE;
   exit 1;
}

unless ((defined $opts{'c'}) && (defined $opts{'w'})) {
   print $USAGE;
   exit 1;
}

if (defined $opts{'w'}) {
    @paraw = split(/,/,$opts{'w'});
        $cpu_w = $paraw[0];
	$mem_w = $paraw[1];  
}
if (defined $opts{'c'}) {
    @parac = split(/,/,$opts{'c'});
        $cpu_c = $parac[0];
        $mem_c = $parac[1];
}



## The CPU usage list

my $SLEEPTIME=5;
my ($user1,$nice1,$sys1,$idle1,$iowait1,$irq1,$softirq1);
my ($user2,$nice2,$sys2,$idle2,$iowait2,$irq2,$softirq2);

open (JIFF, "/proc/stat") || die "Can't open /proc/stat file!\n";
while(my $line=<JIFF>){
    if($line=~/^cpu\s+(\d+)\s(\d+)\s(\d+)\s(\d+)\s(\d+)\s(\d+)\s(\d+).*/){
        ($user1,$nice1,$sys1,$idle1,$iowait1,$irq1,$softirq1)=($1,$2,$3,$4,$5,$6,$7);
    }
}
close (JIFF);
sleep $SLEEPTIME;
open (JIFF, "/proc/stat") || die "Can't open /proc/stat file!\n";
while(my $line=<JIFF>){
    if($line=~/^cpu\s+(\d+)\s(\d+)\s(\d+)\s(\d+)\s(\d+)\s(\d+)\s(\d+).*/){
        ($user2,$nice2,$sys2,$idle2,$iowait2,$irq2,$softirq2)=($1,$2,$3,$4,$5,$6,$7);
    }
}
close (JIFF);
my $JIFF_1=$user1+$nice1+$sys1+$idle1+$iowait1+$irq1+$softirq1;
my $JIFF_2=$user2+$nice2+$sys2+$idle2+$iowait2+$irq2+$softirq2;
my $cpu_usage=100-($idle1-$idle2)/($JIFF_1-$JIFF_2)*100;


## The Memory usage list

my ($memtotal,$memfree,$buffers,$cached,$mem_usage);
my $filename='/proc/meminfo';
open my $FILE, '<', $filename or die "Can't open config file:$!";
while (my $line=<$FILE>) {
    if($line=~/^MemTotal:\s+(\d+)\s/){
        $memtotal = $1;
     }elsif($line=~/^MemFree:\s+(\d+)\s/){
        $memfree = $1;
     }elsif($line=~/^Buffers:\s+(\d+)\s/){
        $buffers = $1;
     }elsif($line=~/^Cached:\s+(\d+)\s/){
        $cached = $1;
     }
}

$mem_usage = ($memtotal-$memfree-$buffers-$cached)/$memtotal*100;

if ($cpu_usage < $cpu_w && $mem_usage < $mem_w) {
    printf "OK - CPU Usage:%1.2f%% Mem Usage:%1.2f%% |cusage=%1.2f%%;$cpu_w;$cpu_c;0; musage=%1.2f%%;$mem_w;$mem_c;0;\n",$cpu_usage,$mem_usage,$cpu_usage,$mem_usage;
    exit $STATE_OK;
}elsif ($cpu_usage < $cpu_c && $mem_usage < $mem_c){
    printf "WARNING - CPU Usage:%1.2f%% Mem Usage:%1.2f%% |cusage=%1.2f%%;$cpu_w;$cpu_c;0; musage=%1.2f%%;$mem_w;$mem_c;0;\n",$cpu_usage,$mem_usage,$cpu_usage,$mem_usage;
    exit $STATE_WARNING;
 }else {
    printf "CRITICAL - CPU Usage:%1.2f%% Mem Usage:%1.2f%% |cusage=%1.2f%%;$cpu_w;$cpu_c;0; musage=%1.2f%%;$mem_w;$mem_c;0;\n",$cpu_usage,$mem_usage,$cpu_usage,$mem_usage;
    exit $STATE_CRITICAL; 
}