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-module(supervisor_deadlock).
-compile([export_all,nowarn_export_all]).
%%%-----------------------------------------------------------------
%%% gen_server callbacks
init([child]) ->
case ets:lookup(supervisor_deadlock,fail_start) of
[{fail_start, false}] ->
%% we must not fail on the first init, otherwise supervisor
%% terminates immediately
{ok, []};
[{fail_start, true}] ->
%% A restart frequency of MaxR=8, MaxT=10 should ensure
%% that restart intensity is not reached -> restart loop.
%% (Note that if we use simple_one_for_one, and start
%% 'many' child instances, the restart frequency must be
%% ajusted accordingly.)
timer:sleep(2000), % NOTE: this could be a gen_server call timeout
{stop, error}
end.
handle_call(_Req, _From, State) ->
{reply, ok, State}.
%% Force a restart
handle_cast(restart, State) ->
{stop, error, State}.
handle_info(_Msg, State) ->
{noreply, State}.
terminate(_Reason, _State) ->
ok.
code_change(_OldVsn, State, _Extra) ->
{ok, State}.
%%%-----------------------------------------------------------------
%%% Start child
start_child() ->
gen_server:start_link({local, ?MODULE}, ?MODULE, [child], []).
start_child_noreg() ->
gen_server:start_link(?MODULE, [child], []).
restart_child() ->
gen_server:cast(supervisor_deadlock, restart).
restart_child(Pid) ->
gen_server:cast(Pid, restart).
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