Code review comment for lp:~widelands-dev/widelands/bug-1825932-open-games

I need some help here.

I'd like to get the server name, set in the edit box:

edit_servername_ in internet_lobby.cc

in internet_game.cc to display a chat message to the user
that she/he cannot use the name since another game with the
same name is already open.

How do I do this?