librenms/includes/discovery/fdb-table.inc.php

<?php

// Build a dictionary of vlans in database
use LibreNMS\Config;

$vlans_dict = array();
foreach (dbFetchRows("SELECT `vlan_id`, `vlan_vlan` from `vlans` WHERE `device_id` = ?", array($device['device_id'])) as $vlan_entry) {
    $vlans_dict[$vlan_entry['vlan_vlan']] = $vlan_entry['vlan_id'];
}
$vlans_by_id = array_flip($vlans_dict);

// Build table of existing vlan/mac table
$existing_fdbs = array();
$sql_result = dbFetchRows("SELECT * FROM `ports_fdb` WHERE `device_id` = ?", array($device['device_id']));
foreach ($sql_result as $entry) {
    $existing_fdbs[(int)$entry['vlan_id']][$entry['mac_address']] = $entry;
}

$insert = array(); // populate $insert with database entries
if (file_exists(Config::get('install_dir') . "/includes/discovery/fdb-table/{$device['os']}.inc.php")) {
    require Config::get('install_dir') . "/includes/discovery/fdb-table/{$device['os']}.inc.php";
} elseif ($device['os'] == 'ios' || $device['os'] == 'iosxe') {
    include Config::get('install_dir') . '/includes/discovery/fdb-table/ios.inc.php';
} else {
    // Check generic Q-BRIDGE-MIB and BRIDGE-MIB
    include Config::get('install_dir') . '/includes/discovery/fdb-table/bridge.inc.php';
}

if (!empty($insert)) {
    // synchronize with the database
    foreach ($insert as $vlan_id => $mac_address_table) {
        echo " {$vlans_by_id[$vlan_id]}: ";

        foreach ($mac_address_table as $mac_address_entry => $entry) {
            if ($existing_fdbs[$vlan_id][$mac_address_entry]) {
                $new_port = $entry['port_id'];

                if ($existing_fdbs[$vlan_id][$mac_address_entry]['port_id'] != $new_port) {
                    $port_fdb_id = $existing_fdbs[$vlan_id][$mac_address_entry]['ports_fdb_id'];

                    dbUpdate(
                        array('port_id' => $new_port),
                        'ports_fdb',
                        '`device_id` = ? AND `vlan_id` = ? AND `mac_address` = ?',
                        array($device['device_id'], $vlan_id, $mac_address_entry)
                    );
                    echo 'U';
                } else {
                    echo '.';
                }
                unset($existing_fdbs[$vlan_id][$mac_address_entry]);
            } else {
                $new_entry = array(
                    'port_id' => $entry['port_id'],
                    'mac_address' => $mac_address_entry,
                    'vlan_id' => $vlan_id,
                    'device_id' => $device['device_id'],
                );

                dbInsert($new_entry, 'ports_fdb');
                echo '+';
            }
        }

        echo PHP_EOL;
    }

    // Delete old entries from the database
    foreach ($existing_fdbs as $vlan_id => $entries) {
        foreach ($entries as $entry) {
            dbDelete(
                'ports_fdb',
                '`port_id` = ? AND `mac_address` = ? AND `vlan_id` = ? and `device_id` = ?',
                array($entry['port_id'], $entry['mac_address'], $entry['vlan_id'], $entry['device_id'])
            );
            d_echo("Deleting: {$entry['mac_address']}\n", '-');
        }
    }
}

unset(
    $vlan_entry,
    $vlans_by_id,
    $existing_fdbs,
    $portid_dict,
    $vlans_dict,
    $insert,
    $sql_result,
    $vlans,
    $port,
    $fdbPort_table,
    $entries
);