From b6541d133f166a3f28cc3b2daf14c59024312c60 Mon Sep 17 00:00:00 2001 From: Raimo Niskanen Date: Wed, 17 Aug 2016 14:29:43 +0200 Subject: Handle exceptions in init/1 and callback_mode/0 --- lib/stdlib/src/gen_statem.erl | 119 +++++++++++++++++++++++++----------------- 1 file changed, 72 insertions(+), 47 deletions(-) (limited to 'lib/stdlib/src/gen_statem.erl') diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl index 7e4fab5365..eee7d60e9d 100644 --- a/lib/stdlib/src/gen_statem.erl +++ b/lib/stdlib/src/gen_statem.erl @@ -557,9 +557,15 @@ init_it(Starter, Parent, ServerRef, Module, Args, Opts) -> Result -> init_result(Starter, Parent, ServerRef, Module, Result, Opts); Class:Reason -> + Stacktrace = erlang:get_stacktrace(), + Name = gen:get_proc_name(ServerRef), gen:unregister_name(ServerRef), proc_lib:init_ack(Starter, {error,Reason}), - erlang:raise(Class, Reason, erlang:get_stacktrace()) + error_info( + Class, Reason, Stacktrace, + #{name => Name, callback_mode => undefined}, + [], [], undefined), + erlang:raise(Class, Reason, Stacktrace) end. %%--------------------------------------------------------------------------- @@ -582,8 +588,14 @@ init_result(Starter, Parent, ServerRef, Module, Result, Opts) -> proc_lib:init_ack(Starter, ignore), exit(normal); _ -> + Name = gen:get_proc_name(ServerRef), + gen:unregister_name(ServerRef), Error = {bad_return_from_init,Result}, proc_lib:init_ack(Starter, {error,Error}), + error_info( + error, Error, ?STACKTRACE(), + #{name => Name, callback_mode => undefined}, + [], [], undefined), exit(Error) end. @@ -835,31 +847,6 @@ loop_events_done(Parent, Debug, S, Timer, State, Data, P, Hibernate) -> timer := Timer}, loop(Parent, Debug, NewS). -loop_event( - Parent, Debug, - #{callback_mode := undefined, - module := Module} = S, - Events, - State, Data, P, Event, Hibernate) -> - %% Cache the callback_mode() value - case - try Module:callback_mode() - catch - Result -> Result - end - of - CallbackMode -> - case callback_mode(CallbackMode) of - true -> - loop_event( - Parent, Debug, - S#{callback_mode := CallbackMode}, - Events, - State, Data, P, Event, Hibernate); - false -> - error({callback_mode,CallbackMode}) - end - end; loop_event( Parent, Debug, #{callback_mode := CallbackMode, @@ -878,22 +865,36 @@ loop_event( %% try case CallbackMode of + undefined -> + Module:callback_mode(); state_functions -> - Module:State(Type, Content, Data); + erlang:apply(Module, State, [Type,Content,Data]); handle_event_function -> Module:handle_event(Type, Content, State, Data) - end of + end + of + Result when CallbackMode =:= undefined -> + loop_event_callback_mode( + Parent, Debug, S, Events, State, Data, P, Event, Result); Result -> loop_event_result( Parent, Debug, S, Events, State, Data, P, Event, Result) catch + Result when CallbackMode =:= undefined -> + loop_event_callback_mode( + Parent, Debug, S, Events, State, Data, P, Event, Result); Result -> loop_event_result( Parent, Debug, S, Events, State, Data, P, Event, Result); - error:badarg when CallbackMode =:= state_functions -> + error:badarg -> case erlang:get_stacktrace() of - [{erlang,apply,[Module,State,_],_}|Stacktrace] -> - Args = [Type,Content,Data], + [{erlang,apply, + [Module,State,[Type,Content,Data]=Args], + _} + |Stacktrace] + when CallbackMode =:= state_functions -> + %% We get here e.g if apply fails + %% due to State not being an atom terminate( error, {undef_state_function,{Module,State,Args}}, @@ -905,24 +906,29 @@ loop_event( Debug, S, [Event|Events], State, Data, P) end; error:undef -> - %% Process an undef to check for the simple mistake + %% Process undef to check for the simple mistake %% of calling a nonexistent state function + %% to make the undef more precise case erlang:get_stacktrace() of - [{Module,State, - [Type,Content,Data]=Args, - _} + [{Module,callback_mode,[]=Args,_} |Stacktrace] - when CallbackMode =:= state_functions -> + when CallbackMode =:= undefined -> + terminate( + error, + {undef_callback,{Module,callback_mode,Args}}, + Stacktrace, + Debug, S, [Event|Events], State, Data, P); + [{Module,State,[Type,Content,Data]=Args,_} + |Stacktrace] + when CallbackMode =:= state_functions -> terminate( error, {undef_state_function,{Module,State,Args}}, Stacktrace, Debug, S, [Event|Events], State, Data, P); - [{Module,handle_event, - [Type,Content,State,Data]=Args, - _} + [{Module,handle_event,[Type,Content,State,Data]=Args,_} |Stacktrace] - when CallbackMode =:= handle_event_function -> + when CallbackMode =:= handle_event_function -> terminate( error, {undef_state_function,{Module,handle_event,Args}}, @@ -940,6 +946,25 @@ loop_event( Debug, S, [Event|Events], State, Data, P) end. +%% Interpret callback_mode() result +loop_event_callback_mode( + Parent, Debug, S, Events, State, Data, P, Event, CallbackMode) -> + case callback_mode(CallbackMode) of + true -> + Hibernate = false, % We have already GC:ed recently + loop_event( + Parent, Debug, + S#{callback_mode := CallbackMode}, + Events, + State, Data, P, Event, Hibernate); + false -> + terminate( + error, + {bad_return_from_callback_mode,CallbackMode}, + ?STACKTRACE(), + Debug, S, [Event|Events], State, Data, P) + end. + %% Interpret all callback return variants loop_event_result( Parent, Debug, S, Events, State, Data, P, Event, Result) -> @@ -1208,8 +1233,9 @@ terminate( C:R -> ST = erlang:get_stacktrace(), error_info( - C, R, ST, Debug, S, Q, P, + C, R, ST, S, Q, P, format_status(terminate, get(), S, State, Data)), + sys:print_log(Debug), erlang:raise(C, R, ST) end, case Reason of @@ -1218,8 +1244,9 @@ terminate( {shutdown,_} -> ok; _ -> error_info( - Class, Reason, Stacktrace, Debug, S, Q, P, - format_status(terminate, get(), S, State, Data)) + Class, Reason, Stacktrace, S, Q, P, + format_status(terminate, get(), S, State, Data)), + sys:print_log(Debug) end, case Stacktrace of [] -> @@ -1229,7 +1256,7 @@ terminate( end. error_info( - Class, Reason, Stacktrace, Debug, + Class, Reason, Stacktrace, #{name := Name, callback_mode := CallbackMode}, Q, P, FmtData) -> {FixedReason,FixedStacktrace} = @@ -1296,9 +1323,7 @@ error_info( case FixedStacktrace of [] -> []; _ -> [FixedStacktrace] - end), - sys:print_log(Debug), - ok. + end). %% Call Module:format_status/2 or return a default value -- cgit v1.2.3