%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2016. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%
%%
%% Supervisor for the entire Mnesia application
-module(mnesia_sup).
-behaviour(application).
-behaviour(supervisor).
-export([start/0, start/2, init/1, stop/1, start_event/0, kill/0]).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% application and suprvisor callback functions
start(normal, Args) ->
SupName = {local,?MODULE},
case supervisor:start_link(SupName, ?MODULE, [Args]) of
{ok, Pid} ->
{ok, Pid, {normal, Args}};
Error ->
Error
end;
start(_, _) ->
{error, badarg}.
start() ->
SupName = {local,?MODULE},
supervisor:start_link(SupName, ?MODULE, []).
stop(_StartArgs) ->
ok.
init([]) -> % Supervisor
init();
init([[]]) -> % Application
init();
init(BadArg) ->
{error, {badarg, BadArg}}.
init() ->
Flags = {one_for_all, 0, 3600}, % Should be rest_for_one policy
Event = event_procs(),
Kernel = kernel_procs(),
{ok, {Flags, Event ++ Kernel}}.
event_procs() ->
KillAfter = timer:seconds(30),
KA = mnesia_kernel_sup:supervisor_timeout(KillAfter),
E = mnesia_event,
[{E, {?MODULE, start_event, []}, permanent, KA, worker, [E, gen_event]}].
kernel_procs() ->
K = mnesia_kernel_sup,
KA = infinity,
[{K, {K, start, []}, permanent, KA, supervisor, [K, supervisor]}].
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% event handler
start_event() ->
case gen_event:start_link({local, mnesia_event}) of
{ok, Pid} ->
case add_event_handler() of
ok ->
{ok, Pid};
Error ->
Error
end;
Error ->
Error
end.
add_event_handler() ->
Handler = mnesia_monitor:get_env(event_module),
gen_event:add_handler(mnesia_event, Handler, []).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% debug functions
kill() ->
Mnesia = [mnesia_fallback | mnesia:ms()],
Kill = fun(Name) -> catch exit(whereis(Name), kill) end,
lists:foreach(Kill, Mnesia),
lists:foreach(fun ensure_dead/1, Mnesia),
timer:sleep(10),
case lists:keymember(mnesia, 1, application:which_applications()) of
true -> kill();
false -> ok
end.
ensure_dead(Name) ->
case whereis(Name) of
undefined ->
ok;
Pid when is_pid(Pid) ->
exit(Pid, kill),
timer:sleep(10),
ensure_dead(Name)
end.