simple loginout links

I’m searching for the code or info on adding simple Login logout links, to the top of my theme, and have it show “welcome User – Dashboard” after they are logged in. Could someone show me or direct me to a page with info on how I can do this?

I want it to appear like wordpress.org does after you login.

Here is what I have of a working code so far, but I don’t know how to add the “welcome Username” to it

<?php if ( is_user_logged_in() ) { echo "<a href='" . get_option('siteurl') . "/wp-admin/'>Site Admin</a> |"; } ?> <?php wp_loginout(); ?>