MP Lobby: refactor use of exception out of lobby config reload request

src/game_initialization/lobby_reload_request_exception.hpp

@@ -1,28 +0,0 @@
-/*
-   Copyright (C) 2015 - 2016 by Chris Beck <render787@gmail.com>
-   Part of the Battle for Wesnoth Project http://www.wesnoth.org/
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY.
-
-   See the COPYING file for more details.
-*/
-#ifndef LOBBY_RELOAD_REQUEST_EXCEPTION_HPP_INCLUDED
-#define LOBBY_RELOAD_REQUEST_EXCEPTION_HPP_INCLUDED
-
-#include <exception>
-#include <string>
-
-namespace mp {
-
-struct lobby_reload_request_exception : game::error {
-	lobby_reload_request_exception() : game::error("Lobby requested to reload the game config and launch again") {}
-};
-
-}
-
-#endif

src/game_initialization/multiplayer.cpp

@@ -18,7 +18,6 @@
 #include "config_assign.hpp"
 #include "formula/string_utils.hpp"
 #include "game_config_manager.hpp"
-#include "game_initialization/lobby_reload_request_exception.hpp"
 #include "game_initialization/mp_game_utils.hpp"
 #include "game_initialization/playcampaign.hpp"
 #include "game_preferences.hpp"
@@ -443,7 +442,7 @@ static void enter_create_mode(mp_workflow_helper_ptr helper)
 	}
 }
 
-static void enter_lobby_mode(mp_workflow_helper_ptr helper, const std::vector<std::string>& installed_addons)
+static bool enter_lobby_mode(mp_workflow_helper_ptr helper, const std::vector<std::string>& installed_addons)
 {
 	DBG_MP << "entering lobby mode" << std::endl;
 
@@ -500,11 +499,16 @@ static void enter_lobby_mode(mp_workflow_helper_ptr helper, const std::vector<st
 				}
 
 				break;
+			case gui2::dialogs::mp_lobby::RELOAD_CONFIG:
+				// Let this function's caller reload the config and re-call.
+				return false;
 			default:
 				// Needed to handle the Quit signal and exit the loop
-				return;
+				return true;
 		}
 	}
+
+	return true;
 }
 
 /** Pubic entry points for the MP workflow */
@@ -529,24 +533,22 @@ void start_client(CVideo& video, const config& game_config,	saved_game& state, c
 	}
 
 	mp_workflow_helper_ptr workflow_helper;
-	bool re_enter;
+	bool re_enter = false;
 
 	do {
 		workflow_helper.reset(new mp_workflow_helper(video, *game_config_ptr, state, connection.get(), nullptr));
-		re_enter = false;
 
-		try {
-			enter_lobby_mode(workflow_helper, installed_addons);
-		} catch(lobby_reload_request_exception&) {
-			re_enter = true;
+		// A return of false means a config reload was requested, so do that and then loop.
+		re_enter = !enter_lobby_mode(workflow_helper, installed_addons);
 
+		if(re_enter) {
 			game_config_manager* gcm = game_config_manager::get();
 			gcm->reload_changed_game_config();
 			gcm->load_game_config_for_game(state.classification()); // NOTE: Using reload_changed_game_config only doesn't seem to work here
 
 			game_config_ptr = &gcm->game_config();
 
-			installed_addons = ::installed_addons(); // Refersh the installed add-on list for this session.
+			installed_addons = ::installed_addons(); // Refresh the installed add-on list for this session.
 
 			connection->send_data(config("refresh_lobby"));
 		}

src/gui/dialogs/lobby/lobby.cpp

@@ -45,7 +45,6 @@
 #include "formatter.hpp"
 #include "formula/string_utils.hpp"
 #include "game_preferences.hpp"
-#include "game_initialization/lobby_reload_request_exception.hpp"
 #include "gettext.hpp"
 #include "lobby_preferences.hpp"
 #include "playmp_controller.hpp"
@@ -930,10 +929,6 @@ static bool handle_addon_requirements_gui(CVideo& v, const std::vector<mp::game_
 			// Begin download session
 			ad_hoc_addon_fetch_session(v, needs_download);
 
-			// TODO: get rid of evil exception throwing. Boooo! In any case, this is here to reload the game config
-			// and the installed_addons list that the lobby has.
-			throw mp::lobby_reload_request_exception();
-
 			return true;
 		}
 	}
@@ -970,6 +965,11 @@ bool mp_lobby::do_game_join(int idx, bool observe)
 
 		if(!handle_addon_requirements_gui(window_->video(), game.required_addons, game.addons_outcome)) {
 			return false;
+		} else {
+			// Addons have been downloaded, so the game_config and installed addons list need to be reloaded.
+			// The lobby is closed and reopened.
+			window_->set_retval(RELOAD_CONFIG);
+			return false;
 		}
 	}
 

src/gui/dialogs/lobby/lobby.hpp

@@ -99,7 +99,8 @@ public:
 		QUIT,
 		JOIN,
 		OBSERVE,
-		CREATE
+		CREATE,
+		RELOAD_CONFIG
 	};
 
 protected: