secure_include

<?php
    // You can modify the second value to change the fallback page (eg., you could make it redirect to an error page).
    define("FALLBACK_PAGE", "news_en.php");

    /// secure_include
    /// string $file : file to include
    /// If the given $file is not in the working directory, includes FALLBACK_PAGE. Else, includes $file.
    function secure_include($file)
    {
        addslashes($file);

        if($file == 'div_en.php' || $file == 'div.php' || !in_array($file, scandir(getcwd())))
            include(FALLBACK_PAGE);
        else
            include($file);
    }
?>