librenms-librenms/includes/discovery/ports-stack.inc.php

<?php

echo("Port Stack: ");

$sql = "SELECT * FROM `ports_stack` WHERE `device_id` = '".$device['device_id']."'";
$query = mysql_query($sql);
while($entry = mysql_fetch_assoc($query))
{
  $stack_db_array[$entry['interface_id_high']][$entry['interface_id_low']]['ifStackStatus'] = $entry['ifStackStatus'];
}

$stack_poll_array = snmpwalk_cache_twopart_oid($device, "ifStackStatus", array());

foreach($stack_poll_array as $interface_id_high => $entry_high)
{
  foreach($entry_high as $interface_id_low => $entry_low)
  {
    $ifStackStatus = $entry_low['ifStackStatus'];
    if(isset($stack_db_array[$interface_id_high][$interface_id_low]))
    {
      if($stack_db_array[$interface_id_high][$interface_id_low]['ifStackStatus'] == $ifStackStatus)
      {
        echo(".");
      } else {
        mysql_query("UPDATE `ports_stack` SET `ifStackStatus` = '".$ifStackStatus."' WHERE `device_id` = '".$device['device_id']."' AND `interface_id_high` = '".$interface_id_high."' AND `interface_id_low` = '".$interface_id_low."'");
        echo("U");
        if($debug) { echo(mysql_error()); }
      }
      unset($stack_db_array[$interface_id_high][$interface_id_low]);
    } else {
      mysql_query("INSERT INTO `ports_stack` (`device_id`,`interface_id_high`,`interface_id_low`,`ifStackStatus`)  VALUES ('".$device['device_id']."','".$interface_id_high."','".$interface_id_low."','".$ifStackStatus."')");
      echo("+");
      if($debug) { echo(mysql_error()); }
    }
  }
}

echo("\n");

?>