#!/usr/bin/perl -w
# Copyright (C) 2009-2011 Glen Pitt-Pladdy
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
#
#
# See: http://www.pitt-pladdy.com/blog/_20091031-144604_0000_SMART_stats_on_Cacti_via_SNMP_/
#
# Put SMART parameter ID on command line, prefixed by 'R' if you want raw value
#
# Put "worst" on the command line and the smallest gap to threshold of all
# parameters will be output.

$FILES = '/var/local/snmp/smart';

$param = shift @ARGV;
if ( $param eq 'devices' ) {
	$devicelist = 1;
} elsif ( $param =~ /^worst$/i ) {
	$worst = 1;
} elsif ( $param =~ s/^[rR](\d+)$/$1/ ) {
	$raw = 1;
} elsif ( $param =~ /^\d+$/ ) {
	$raw = 0;
} else {
	die "FATAL - need the numeric parameter to show\n";
}

# run through current drives
opendir LS, "/dev" or die "FATAL - can't list /dev: $!\n";
while ( defined ( $drive = readdir LS ) ) {
	if ( $drive !~ /^sd[a-z]$/ ) { next; }	# skip non drives
	push @drives, $drive
}
closedir LS;

if ( $devicelist ) {
	foreach $drive (sort @drives) {
		print "/dev/$drive\n";
	}
	exit 0;
}

foreach $drive (sort @drives) {
	# deal with missing files
	if ( ! -f "$FILES-$drive" ) {
		print "NA\n";
		next;
	}
	# grab the parameter from the file
	open DR, "$FILES-$drive"
		or die "FATAL - can't read \"$FILES-$drive\": $!\n";
	while ( defined ( $line = <DR> )
		and $line !~ /^ID#\s+ATTRIBUTE_NAME\s+FLAG\s+VALUE\s+WORST\s+THRESH/ )
		{}
	$worstcase = 255;
	undef $health;
	while ( defined ( $line = <DR> ) ) {
		chomp $line;
		if ( $line eq '' ) { last; }
		$line =~ s/^\s*//;
		@fields = split /\s+/, $line;
		if ( $worst ) {
			$health = $fields[3] - $fields[5];
			if ( $health < $worstcase ) {
				$worstcase = $health;
			}
			next;	# go no further
		}
		if ( $fields[0] != $param ) { next; }
		if ( $raw ) {
			$health = $fields[9];
			# we want the raw value
			print "$health\n";
		} else {
			# how close are we to threshold?
			$health = $fields[3] - $fields[5];
			print "$health\n";
			last;
		}
	}
	close DR;
	if ( $worst ) {
		print "$worstcase\n";
	} elsif ( ! defined ( $health ) ) {
		# didn't get the parameter
		print "NA\n";
	}
}