#!/usr/bin/perl -w

use strict;
use Getopt::Std;

sub warning {
	print "@_\n";
	exit(1);
}

sub critical {
	print "@_\n";
	exit(2);
}

sub unknown {
	print "@_\n";
	exit(3);
}

sub success {
	print "@_\n";
	exit(0);
}

sub usage {
	print "Usage: $0\n\n";
	print "\t -H \t Hostaddress \t\t\t\t (required)\n";
	print "\t -C \t Community \t\t\t\t (required)\n";
	print "\t -p \t Partition to check \t\t\t (required)\n";
	print "\t -c \t Critical level used space in percent \t (required)\n";
	print "\t -w \t Warning level used space in percent \t (required)\n";
	print "\t -h \t Show this help information\n\n";
	exit(1);
}

$SIG{ALRM} = \&critical;
alarm(295);

my %opts;

getopts('H:C:p:c:w:h:', \%opts);

my $host = $opts{"H"};
my $comm = $opts{"C"};
my $part = $opts{"p"};
my $crit = $opts{"c"};
my $warn = $opts{"w"};
my $help = $opts{"h"};

if (defined($help)) {
	usage();
}

if (defined($host) && defined($comm) && defined ($part) && defined($crit) && defined($warn)) {
	
	my $hddInfo=`snmpdf -v1 -c $comm $host | grep $part | head -1`;
	chomp $hddInfo;
	my @diskInfo=split(/\s+/, $hddInfo);
	my $diskMount=$diskInfo[0];

	if (defined($diskMount)) {

		my $diskSize=int($diskInfo[1]);
		my $diskUsed=int($diskInfo[2]);
		my $diskLeft=int($diskInfo[3]);

		my $diskSizeGB=(($diskSize/1024)/1024);
		$diskSizeGB=~/(\d+\.\d{2})/;
		$diskSizeGB=$1;

		my $diskLeftGB=(($diskLeft/1024)/1024);
		$diskLeftGB=~/(\d+\.\d{2})/;
		$diskLeftGB=$1;

		my $diskUsedP=(($diskUsed/$diskSize)*100);
		$diskUsedP=~/(\d+\.\d{2})/;
		$diskUsedP=$1;
		

		if ($diskMount eq $part) {
			if ($diskUsedP > $crit) {
				critical("CRITICAL: $diskUsedP% used on $diskMount ($diskLeftGB GB left of $diskSizeGB GB)");
			} elsif ($diskUsedP > $warn) {
				warning("WARNING: $diskUsedP% used on $diskMount ($diskLeftGB GB left of $diskSizeGB GB)");
			} else {
				success("DISK OK: $diskUsedP% used on $diskMount ($diskLeftGB GB left of $diskSizeGB GB)");
			}
		} else {
			critical("CRITICAL: $part not mounted.");
		}
	} else {
		critical("CRITICAL: No output!");
	}
	
} else {
	usage();
}