Separate the game process exit monitoring into its own general-purpose module.

ebin/egs.app

@@ -6,6 +6,7 @@
 		egs,
 		egs_app,
 		egs_sup,
+		egs_exit_mon,
 		reloader,
 		egs_cron,
 		egs_db,

src/egs_exit_mon.erl

@@ -0,0 +1,47 @@
+%% @author Loïc Hoguin <essen@dev-extend.eu>
+%% @copyright 2010 Loïc Hoguin.
+%% @doc General purpose module for monitoring exit signals of linked processes.
+%%
+%%	This file is part of EGS.
+%%
+%%	EGS 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 3 of the License, or
+%%	(at your option) any later version.
+%%
+%%	EGS is distributed in the hope that it will be useful,
+%%	but WITHOUT ANY WARRANTY; without even the implied warranty of
+%%	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+%%	GNU General Public License for more details.
+%%
+%%	You should have received a copy of the GNU General Public License
+%%	along with EGS.  If not, see <http://www.gnu.org/licenses/>.
+
+-module(egs_exit_mon).
+-export([start_link/1]). %% External.
+-export([start/1, loop/1]). %% Internal.
+
+%% @spec start_link(CleanupFn) -> {ok,Pid::pid()}
+%% @doc Start the monitor and return the process' Pid.
+start_link(CallbackFn) ->
+	Pid = spawn(?MODULE, start, [CallbackFn]),
+	{ok, Pid}.
+
+%% @spec start(CallbackFn) -> ok
+%% @doc Start the main loop.
+start(CallbackFn) ->
+	process_flag(trap_exit, true),
+	?MODULE:loop(CallbackFn).
+
+%% @spec loop(CallbackFn) -> ok
+%% @doc Main loop, trap exit messages and call the callback function.
+loop(CallbackFn = {Module, Function}) ->
+	receive
+		{'EXIT', Pid, _} ->
+			spawn(Module, Function, [Pid]);
+		_ ->
+			reload
+	after 5000 ->
+		reload
+	end,
+	?MODULE:loop(CallbackFn).

src/psu/psu_game.erl

@@ -18,8 +18,8 @@
 %%	along with EGS.  If not, see <http://www.gnu.org/licenses/>.
 
 -module(psu_game).
--export([start_link/1]). %% External.
+-export([start_link/1, cleanup/1]). %% External.
--export([supervisor_init/0, supervisor/0, listen/2, accept/2, process_init/2, process/0, char_select/0, area_load/4, loop/1]). %% Internal.
+-export([listen/2, accept/2, process_init/2, process/0, char_select/0, area_load/4, loop/1]). %% Internal.
 
 -include("include/records.hrl").
 -include("include/maps.hrl").
@@ -29,64 +29,41 @@
 %% @spec start_link(Port) -> {ok,Pid::pid()}
 %% @doc Start the game server.
 start_link(Port) ->
-	SPid = spawn(?MODULE, supervisor_init, []),
+	{ok, MPid} = egs_exit_mon:start_link({?MODULE, cleanup}),
-	LPid = spawn(?MODULE, listen, [Port, SPid]),
+	LPid = spawn(?MODULE, listen, [Port, MPid]),
 	{ok, LPid}.
 
-%% @doc Game processes supervisor initialization.
+%% @spec cleanup(Pid) -> ok
-
+%% @doc Cleanup the data associated with the failing process.
-supervisor_init() ->
+cleanup(Pid) ->
-	process_flag(trap_exit, true),
+	User = egs_db:users_select_by_pid(Pid),
-	supervisor().
+	egs_db:users_delete(User#users.gid),
-
+	lists:foreach(fun(Other) -> Other#users.pid ! {psu_player_unspawn, User} end, egs_db:users_select_others_in_area(User)),
-%% @doc Game processes supervisor. Make sure everything is cleaned up when an unexpected error occurs.
+	io:format("game (~p): quit~n", [User#users.gid]).
-
-supervisor() ->
-	receive
-		{'EXIT', Pid, _} ->
-			supervisor_close(Pid);
-		_ ->
-			reload
-	after 5000 ->
-		reload
-	end,
-	?MODULE:supervisor().
-
-%% @doc Close the connection for the given user and cleanup.
-
-supervisor_close(Pid) ->
-	try
-		User = egs_db:users_select_by_pid(Pid),
-		egs_db:users_delete(User#users.gid),
-		lists:foreach(fun(Other) -> Other#users.pid ! {psu_player_unspawn, User} end, egs_db:users_select_others_in_area(User)),
-		io:format("game (~p): quit~n", [User#users.gid])
-	catch _:_ ->
-		ignore
-	end.
 
 %% @doc Listen for connections.
 
-listen(Port, SPid) ->
+listen(Port, MPid) ->
 	{ok, LSocket} = ssl:listen(Port, ?OPTIONS),
-	?MODULE:accept(LSocket, SPid).
+	?MODULE:accept(LSocket, MPid).
 
 %% @doc Accept connections.
 
-accept(LSocket, SPid) ->
+accept(LSocket, MPid) ->
 	case ssl:transport_accept(LSocket, 5000) of
 		{ok, CSocket} ->
 			ssl:ssl_accept(CSocket),
-			Pid = spawn(?MODULE, process_init, [CSocket, SPid]),
+			Pid = spawn(?MODULE, process_init, [CSocket, MPid]),
 			ssl:controlling_process(CSocket, Pid);
 		_ ->
 			reload
 	end,
-	?MODULE:accept(LSocket, SPid).
+	?MODULE:accept(LSocket, MPid).
 
 %% @doc Initialize the client process by saving the socket to the process dictionary.
 
-process_init(CSocket, SPid) ->
+process_init(CSocket, MPid) ->
-	link(SPid),
+	link(MPid),
 	put(socket, CSocket),
 	send_0202(),
 	process().