librenms-librenms/includes/include-dir.inc.php

<?php

// This is an include so that we don't lose variable scope.
if ($include_dir_regexp == '' || !isset($include_dir_regexp)) {
    $include_dir_regexp = '/\.inc\.php$/';
}

if ($handle = opendir($config['install_dir'].'/'.$include_dir)) {
    while (false !== ($file = readdir($handle))) {
        if (filetype($config['install_dir'].'/'.$include_dir.'/'.$file) == 'file' && preg_match($include_dir_regexp, $file)) {
            if ($debug) {
                echo 'Including: '.$config['install_dir'].'/'.$include_dir.'/'.$file."\n";
            }

            include $config['install_dir'].'/'.$include_dir.'/'.$file;
        }
    }

    closedir($handle);
}

unset($include_dir_regexp, $include_dir);