#!/usr/bin/perl -w

=head1 NAME

check_du.pl - Nagios plugin for checking size of directories and files

=head1 SYNOPSIS

 check_du.pl -P path/pattern [-v] \
             [-w warning_threshold] [-c critical_threshold]
 check_du.pl [-h|-V]

=head1 OPTIONS

=over 4

=item -P|--path=expression

Path expression for calculating size. May be a shell expression like
/var/log/*.log

=item -w|--warning=threshold

threshold can be max (warn if < 0 or > max), min:max (warn if < min or >
max), min: (warn if < min), or @min:max (warn if >= min and <= max). All
values must be integer.

=item -c|--critical=threshold

see --warning for explanation of threshold format

=item -v|--verbose

increases verbosity, specify twice to see the original output from sapinfo.

=item -V|--version

print version an exit

=item -h|--help

print help message and exit

=cut

use strict;
use warnings;
use Nagios::Plugin 0.15;
use Getopt::Long qw(:config no_ignore_case bundling);
use Pod::Usage;

my $np = Nagios::Plugin->new( shortname => "CHECK_DU" );
my $line = '';
my $warn_threshold = '0:';
my $crit_threshold = '0:';
my $what = '';
my $denied = 0;
my $size = 0;
my $result = UNKNOWN;
my $version = 'V1.0/2007-01-28/wob';
my $printversion = 0;
my $verbose = 0;
my $help = 0;

# -- GetOpt
GetOptions(
   "P|path=s"           => \$what,
   "w|warning=s"        => \$warn_threshold,
   "c|critical=s"       => \$crit_threshold,
   "h|help"             => \$help,
   "V|version"          => \$printversion,
   "v|verbose+"         => \$verbose,
) or pod2usage({ -exitval => UNKNOWN,
                 -verbose => 0,
                 -msg     => "*** unknown argument found ***" });

pod2usage(-verbose => 2,
          -exitval => UNKNOWN
         ) if ( $help );

pod2usage(-msg     => "\n$0 -- version: $version\n",
          -verbose => 0,
          -exitval => UNKNOWN 
         ) if ( $printversion );

pod2usage(-msg     => "*** no path/pattern specified ***",
          -verbose => 0,
          -exitval => UNKNOWN
         ) if ( "$what" eq "" );

# -- thresholds
$np->set_thresholds( 
   warning  => $warn_threshold,
   critical => $crit_threshold);

# -- main
open ( OUT, "LANG=C; /usr/bin/du -cs $what 2>&1 |" ) 
   or $np->nagios_die( "can't start /usr/bin/du" );

0while (<OUT>) {
   print "$_" if ($verbose);
   chomp $_;
   my $line = $_;
   $denied++ if ( /Permission denied/i );

   if ( /^(\d+)\s+total$/i ) {	# last line
      $size = $1;
      last;
   }
}
close (OUT);

$np->add_perfdata( label => "size", value => $size, 
                   uom => "kB", threshold => $np->threshold() );

if ( $denied ) { 
   $np->nagios_exit( CRITICAL, "unreadable directories or files");
}

$result = $np->check_threshold(  $size );

$np->nagios_exit( $result, "check size: $size kByte");