#!/usr/local/apps/perl-5.005_03/bin/perl

# This thing produces a report detailing what has change in the
# named filesystem.

# Scraped together by Matt McLeod <matt@boggle.org>
# See http://boggle.org/software/ for license details.

# Last modified 20001104.

use Mail::Mailer;

$filebase = "/var/tmp/fsmon";
@monfs = ();
$tempfile = "/var/tmp/fsmon.tmp";
$gzip = "/usr/local/bin/gzip";

%headers = ( From => "System Monitor <asacadm\@asac.ericsson.se>",
	     To => "asacadm-reports\@asac.ericsson.se",
	     Subject => "Daily fsmon report"
	   );

while ($n = shift) {
	push @monfs, $n;
};

$mailer = new Mail::Mailer 'smtp', Server => 'assc00.epa.ericsson.se';
$mailer->open(\%headers);

foreach $fs (@monfs) { 

# initialize hashes

	%hist_size = ();
	%cur_size = ();

# read in historical data, if any exists

	$fname = $fs;
	$fname =~ s/\s|:|\\|\//_/g;

	if ( -f "$filebase/$fname.yesterday.gz" ) {
		open (YESTERDAY,"$gzip -dc $filebase/$fname.yesterday.gz |");
		while (<YESTERDAY>) {
			chomp($_);
			($node, $size) = split(";",$_);
			$hist_size{$node} = $size;
		};
		close(YESTERDAY);
	};

# fetch current data (will take a while...)

	chdir($fs);

	open(DU,"/bin/du -dk . |") || die "can't run du!";

	while(<DU>) {
		chomp($_);
		($size, $node) = split(" ",$_);
		$cur_size{$node} = $size;
	};

	close(DU);

# generate the report

	print $mailer "\nFilesystem: $fs\n\n";

	print $mailer "New nodes:\n";

	foreach $n (sort keys(%cur_size)) {
		print $mailer "$n\n" if ($hist_size{$n} == undef);
	};

	print $mailer "\nVanished nodes:\n";

	foreach $n (sort keys(%hist_size)) {
		print $mailer "$n\n" if ($cur_size{$n} == undef);
	};

	print $mailer "\nChanged nodes:\n\n";

	open(TEMPFILE,">$tempfile");

	print TEMPFILE <<EOText;
Node                                        Old size   New size     Change
--------------------------------------------------------------------------
EOText

	format TEMPFILE =
^<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< @>>>>>>>>> @>>>>>>>>> @>>>>>>>>>
$nodename,                                $oldsize,  $newsize,  $change
.

	foreach $n (sort keys(%cur_size)) {
		if ($hist_size{$n} != undef) {
			$change = $cur_size{$n} - $hist_size{$n};
			$oldsize = $hist_size{$n};
			$newsize = $cur_size{$n};
			$nodename = $n;
			if ($change != 0) {
				write TEMPFILE;
			};
		};
	};

	close (TEMPFILE);

	open(TEMPFILE,"<$tempfile");

	while (<TEMPFILE>) {
		print $mailer $_;
	};

	close(TEMPFILE);

# write current data out as historical

	open(YESTERDAY,"| $gzip -c > $filebase/$fname.yesterday.gz");

	foreach $n (sort keys(%cur_size)) {
		print YESTERDAY "$n;$cur_size{$n}\n";
	};

	close(YESTERDAY);
};

$mailer->close;