//Code auto link
public static function autolink($text) {
function fix($url) {
$img = '/[.](jpg|png|gif|jpeg|bmp)$/i';
$file = '/[.](jar|jad|sis|sisx|mp3|mp4|3gp|amr|mid|avi|flv|zip|rar|7z|tar|gz|apk|exe|msi|gdr|ttf|dll|auto|swf|thm|txt|pdf|doc|xml|rtf)$/i';
if (preg_match($img, $url)) { return ' [img]' . $url . '[/img]'; }
else if (preg_match($file, $url)) { return ' [d]' . $url . '[/d]'; }
else { return ' ' . $url; }
}

$url_match = $url_replace = array();
$url_match[] = '#(^|[\n\t (>.])([a-z][a-z\d+]*:/{2}(??:[a-z0-9\-._~!$&\'(*+,;=:@|]+|%[\dA-F]{2})+|[0-9.]+|\[[a-z0-9.]+:[a-z0-9.]+:[a-z0-9.:]+\])(?::\d*)?(?:/(?:[a-z0-9\-._~!$&\'(*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&\'(*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&\'(*+,;=:@/?|]+|%[\dA-F]{2})*)?)#ieu';
$url_replace[] = "fix('$2')";
return preg_replace($url_match, $url_replace, $text);
}

$biến ra = functions::autolink($biến vào);

$msg = isset($_POST['msg']) ? functions::check(trim($_POST['msg'])) : '';

$msg = isset($_POST['msg']) ? functions::check(functions::autolink(trim($_POST['msg']))) : '';