redcon.Serve() never returns.

[Kenta Iwasaki]

redcon.serve() only returns if (*Server).done is ever set to true, which is only possible if (*Server).Close() is called.

Given that the use of redcon.Serve(ln net.Listener, ...) unlike any of the other methods exposed in the package assumes that the user is not keeping around a *redcon.Server instance, it wouldn't be possible for the user to force redcon.Serve() to ever return, which is behavior that is desired for e.g. graceful shutdown.

Rather than ignoring errors from net.Listener.Accept() in redcon.serve() unless (*Server).done is set to true, what about breaking early from redcon.serve()'s accept loop if an error is returned by net.Listener.Accept() which indicates that the listener is closed?

For example:

lnconn, err := s.ln.Accept()
if err != nil {
    // .....
    if errors.Is(err, net.ErrClosed) {
        return nil
    }
}

[Josh Baker]

Yes. This makes sense. I just pushed a fix that works as you describe.