#!/usr/bin/perl

use Fcntl ':flock';

$ubc_file = '/proc/user_beancounters';
$ubc_prev_file = '/var/tmp/user_beancounters.prev';
$lock_file = '/var/tmp/check_ubc.lock';

open( lfh, '>' . $lock_file ) or die( "$lock_file open error\n" );

unless( flock( lfh, LOCK_EX | LOCK_NB ) )
{
  print "check_ubc locked\n";
  exit;
}

if( -f $ubc_prev_file )
{
  open( fh, $ubc_prev_file ) or die( "$ubc_prev_file open error\n" );

  while( <fh> )
  {
    chomp;

    ( $k, $v ) = split( /\t/ );

    $ubc_prev{ $k } = $v;
  }

  close( fh );
}

open( fh, $ubc_file ) or die( "$ubc_file open error\n" );

$uid = 0;

while( <fh> )
{
  s/^\s+//;
  s/\s+$//;

  next
    if( /^Version/ );

  next
    if( /^uid/ );

  next
    if( /^$/ );

  if( /^(\d+)\:/ )
  {
    $uid = $1;

    @sl = split( /\s+/ );

    $k = $uid . '_' . $sl[ 1 ];
    $v = $sl[ 6 ];
  }
  else
  {
    @sl = split( /\s+/ );

    next
      if( $sl[ 0 ] eq 'dummy' );

    $k = $uid . '_' . $sl[ 0 ];
    $v = $sl[ 5 ];
  }

  $ubc{ $k } = $v;

  if( defined( $ubc_prev{ $k } ) &&
      $ubc{ $k } > $ubc_prev{ $k } )
  {
    print $k . ': ' . $ubc_prev{ $k } . ' -> ' . $v . "\n";
    print;
    print "\n";
  }
}

close( fh );

open( fh, '>' . $ubc_prev_file ) or die( "$ubc_file open error\n" );

for $k ( keys( %ubc ) )
{
  print fh $k . "\t" . $ubc{ $k } . "\n";
}

close( fh );

close( lfh );
exit;