Display post categories

Shortcode usage - [categories-list]  
//shortcode to display post categories
function getCategoriesShortcodeFunc(){
    if(!is_single()) //show on the post page only
        return;
    $categories = get_the_category();
    if(!$categories)
        return;
    $ret_str = '';
    foreach($categories as $category)
    {
        $ret_str.= '<li class="cat-' . $category->cat_ID . '"><a href="'.get_category_link( $category->term_id ).'" title="' . esc_attr($category->name) . '">'.$category->cat_name.'</a></li>';
    }
    $ret_str = '<h5>Categories :</h5><div class="overflow"><ul class="post-categories">' . $ret_str . '</ul></div>';
    return $ret_str;
}

add_shortcode( 'categories-list', 'getCategoriesShortcodeFunc' );
//end shortcode post categories