#!/usr/bin/perl
#
# $Id$
#
# diskspace.pl
# TiChou <tichou@tichou.org>
#
# Require iputils.
#

my $version = "1.0";
my $cmdname = (split('/', $0))[-1];

my $rrdlib = "/var/lib/rrd";

my $df = "/bin/df";

use Getopt::Long;
use RRDs;

sub usage($) {
  my $usage = "Usage: $cmdname [options] device[,device...]
Options:
  -f, --file=FILE[,FILE...]  specify RRD files (default $rrdlib/disk_DEVICE.rrd)

  -h, --help                 display this help and exit
  -v, --version              display version

Report bugs to <tichou\@tichou.org>.\n";

  if (shift) {
    print STDOUT $usage;
    exit 0;
  } else {
    print STDERR $usage;
    exit 1;
  }
}

sub version {
  print "$cmdname $version\n";
  exit 0;
}

my @rrdfiles = ();

Getopt::Long::Configure ("bundling");
GetOptions("f|file=s@" => \@rrdfiles,
           "h|help"    => \&usage,
           "v|version" => \&version) or &usage(0);

my @devices = @ARGV or &usage(0);

@rrdfiles = split(/,/,join(',',@rrdfiles));
@devices = split(/,/,join(',',@devices));

open (DF, "$df -k|") or die "$0: unable to run $df: $!\n";
while (<DF>) {
  /^(\S+)\s+(\d+)\s+\d+\s+(\d+)\s+\d+%\s+\S+$/ && (@$1 = ($2,$3));
};
close (DF);

for (my $i = 0; $i < @devices; $i++) {
  my $device = $devices[$i];
  my $file = $rrdfiles[$i] ? $rrdfiles[$i] : "$rrdlib/disk_".(split('/', $device))[-1].".rrd";
  if (not -f $file) {
    RRDs::create $file, qw(DS:size:GAUGE:600:0:U
                           DS:available:GAUGE:600:0:U
                           RRA:AVERAGE:0.5:1:288
                           RRA:AVERAGE:0.5:6:336
                           RRA:AVERAGE:0.5:24:360
                           RRA:AVERAGE:0.5:288:365
                           RRA:MIN:0.5:1:288
                           RRA:MIN:0.5:6:336
                           RRA:MIN:0.5:24:360
                           RRA:MIN:0.5:288:365
                           RRA:MAX:0.5:1:288
                           RRA:MAX:0.5:6:336
                           RRA:MAX:0.5:24:360
                           RRA:MAX:0.5:288:365);
    my $error = RRDs::error;
    die "$0: $error\n" if $error;
  }
    
  RRDs::update $file, "N:".(@$device ? join(':',@$device) : "U:U");
  my $error = RRDs::error;
  die "$0: $error\n" if $error;
}