common.php 에서

function g5_path()

{

    $chroot = substr($_SERVER['SCRIPT_FILENAME'], 0, strpos($_SERVER['SCRIPT_FILENAME'], dirname(__FILE__)));

    $result['path'] = str_replace('\\', '/', $chroot.dirname(__FILE__));

    $server_script_name = preg_replace('/\/+/', '/', str_replace('\\', '/', $_SERVER['SCRIPT_NAME']));

    $server_script_filename = preg_replace('/\/+/', '/', str_replace('\\', '/', $_SERVER['SCRIPT_FILENAME']));

    $tilde_remove = preg_replace('/^\/\~[^\/]+(.*)$/', '$1', $server_script_name);

    $document_root = str_replace($tilde_remove, '', $server_script_filename);

    $pattern = '/.*?' . preg_quote($document_root, '/') . '/i';

    $root = preg_replace($pattern, '', $result['path']);

    $port = ($_SERVER['SERVER_PORT'] == 80 || $_SERVER['SERVER_PORT'] == 443) ? '' : ':'.$_SERVER['SERVER_PORT'];

    $http = 'http' . ((isset($_SERVER['HTTPS']) && $_SERVER['HTTPS']=='on') ? 's' : '') . '://';

    $user = str_replace(preg_replace($pattern, '', $server_script_filename), '', $server_script_name);

    $host = isset($_SERVER['HTTP_HOST']) ? $_SERVER['HTTP_HOST'] : $_SERVER['SERVER_NAME'];

    if(isset($_SERVER['HTTP_HOST']) && preg_match('/:[0-9]+$/', $host))

        $host = preg_replace('/:[0-9]+$/', '', $host);

    $host = preg_replace("/[\<\>\'\"\\\'\\\"\%\=\(\)\/\^\*]/", '', $host);

    $result['url'] = $http.$host.$port.$user.$root;

    return $result;

}

$g5_path = g5_path();

include_once($g5_path['path'].'/config.php');   // 설정 파일

unset($g5_path);

에서

1. g5_path() 함수는 보안목적상 복잡하게 처리를 하는 것 같은데 맞나요?

2. 다른 파일을 include_once 할 때와 다르게 config.php 만 특별하게 처리하는 이유가 있나요?