From 8276831a98ebe3d3b821ffcc1093acbebf0c6022 Mon Sep 17 00:00:00 2001 From: Siri Hansen Date: Tue, 28 Oct 2014 14:11:20 +0100 Subject: Add stack trace for gen_server exit in ERROR REPORT If a callback function was terminated with exit/1, there would be no stack trace in the ERROR REPORT produced by gen_server. This has been corrected. The actual exit reason for the process is not changed. --- lib/stdlib/src/gen_server.erl | 144 +++++++++++++++++++++++++---------- lib/stdlib/test/gen_server_SUITE.erl | 12 ++- 2 files changed, 113 insertions(+), 43 deletions(-) (limited to 'lib') diff --git a/lib/stdlib/src/gen_server.erl b/lib/stdlib/src/gen_server.erl index dadfe56b3d..528dd23e1c 100644 --- a/lib/stdlib/src/gen_server.erl +++ b/lib/stdlib/src/gen_server.erl @@ -567,28 +567,88 @@ start_monitor(Node, Name) when is_atom(Node), is_atom(Name) -> end end. +%% --------------------------------------------------- +%% Helper functions for try-catch of callbacks. +%% Returns the return value of the callback, or +%% {'EXIT', ExitReason, ReportReason} (if an exception occurs) +%% +%% ExitReason is the reason that shall be used when the process +%% terminates. +%% +%% ReportReason is the reason that shall be printed in the error +%% report. +%% +%% These functions are introduced in order to add the stack trace in +%% the error report produced when a callback is terminated with +%% erlang:exit/1 (OTP-12263). +%% --------------------------------------------------- + +try_dispatch({'$gen_cast', Msg}, Mod, State) -> + try_dispatch(Mod, handle_cast, Msg, State); +try_dispatch(Info, Mod, State) -> + try_dispatch(Mod, handle_info, Info, State). + +try_dispatch(Mod, Func, Msg, State) -> + try + {ok, Mod:Func(Msg, State)} + catch + throw:R -> + {ok, R}; + error:R -> + Stacktrace = erlang:get_stacktrace(), + {'EXIT', {R, Stacktrace}, {R, Stacktrace}}; + exit:R -> + Stacktrace = erlang:get_stacktrace(), + {'EXIT', R, {R, Stacktrace}} + end. + +try_handle_call(Mod, Msg, From, State) -> + try + {ok, Mod:handle_call(Msg, From, State)} + catch + throw:R -> + {ok, R}; + error:R -> + Stacktrace = erlang:get_stacktrace(), + {'EXIT', {R, Stacktrace}, {R, Stacktrace}}; + exit:R -> + Stacktrace = erlang:get_stacktrace(), + {'EXIT', R, {R, Stacktrace}} + end. + +try_terminate(Mod, Reason, State) -> + try + {ok, Mod:terminate(Reason, State)} + catch + throw:R -> + {ok, R}; + error:R -> + Stacktrace = erlang:get_stacktrace(), + {'EXIT', {R, Stacktrace}, {R, Stacktrace}}; + exit:R -> + Stacktrace = erlang:get_stacktrace(), + {'EXIT', R, {R, Stacktrace}} + end. + + %%% --------------------------------------------------- %%% Message handling functions %%% --------------------------------------------------- -dispatch({'$gen_cast', Msg}, Mod, State) -> - Mod:handle_cast(Msg, State); -dispatch(Info, Mod, State) -> - Mod:handle_info(Info, State). - handle_msg({'$gen_call', From, Msg}, Parent, Name, State, Mod) -> - case catch Mod:handle_call(Msg, From, State) of - {reply, Reply, NState} -> + Result = try_handle_call(Mod, Msg, From, State), + case Result of + {ok, {reply, Reply, NState}} -> reply(From, Reply), loop(Parent, Name, NState, Mod, infinity, []); - {reply, Reply, NState, Time1} -> + {ok, {reply, Reply, NState, Time1}} -> reply(From, Reply), loop(Parent, Name, NState, Mod, Time1, []); - {noreply, NState} -> + {ok, {noreply, NState}} -> loop(Parent, Name, NState, Mod, infinity, []); - {noreply, NState, Time1} -> + {ok, {noreply, NState, Time1}} -> loop(Parent, Name, NState, Mod, Time1, []); - {stop, Reason, Reply, NState} -> + {ok, {stop, Reason, Reply, NState}} -> {'EXIT', R} = (catch terminate(Reason, Name, Msg, Mod, NState, [])), reply(From, Reply), @@ -596,26 +656,27 @@ handle_msg({'$gen_call', From, Msg}, Parent, Name, State, Mod) -> Other -> handle_common_reply(Other, Parent, Name, Msg, Mod, State) end; handle_msg(Msg, Parent, Name, State, Mod) -> - Reply = (catch dispatch(Msg, Mod, State)), + Reply = try_dispatch(Msg, Mod, State), handle_common_reply(Reply, Parent, Name, Msg, Mod, State). handle_msg({'$gen_call', From, Msg}, Parent, Name, State, Mod, Debug) -> - case catch Mod:handle_call(Msg, From, State) of - {reply, Reply, NState} -> + Result = try_handle_call(Mod, Msg, From, State), + case Result of + {ok, {reply, Reply, NState}} -> Debug1 = reply(Name, From, Reply, NState, Debug), loop(Parent, Name, NState, Mod, infinity, Debug1); - {reply, Reply, NState, Time1} -> + {ok, {reply, Reply, NState, Time1}} -> Debug1 = reply(Name, From, Reply, NState, Debug), loop(Parent, Name, NState, Mod, Time1, Debug1); - {noreply, NState} -> + {ok, {noreply, NState}} -> Debug1 = sys:handle_debug(Debug, fun print_event/3, Name, {noreply, NState}), loop(Parent, Name, NState, Mod, infinity, Debug1); - {noreply, NState, Time1} -> + {ok, {noreply, NState, Time1}} -> Debug1 = sys:handle_debug(Debug, fun print_event/3, Name, {noreply, NState}), loop(Parent, Name, NState, Mod, Time1, Debug1); - {stop, Reason, Reply, NState} -> + {ok, {stop, Reason, Reply, NState}} -> {'EXIT', R} = (catch terminate(Reason, Name, Msg, Mod, NState, Debug)), _ = reply(Name, From, Reply, NState, Debug), @@ -624,39 +685,39 @@ handle_msg({'$gen_call', From, Msg}, Parent, Name, State, Mod, Debug) -> handle_common_reply(Other, Parent, Name, Msg, Mod, State, Debug) end; handle_msg(Msg, Parent, Name, State, Mod, Debug) -> - Reply = (catch dispatch(Msg, Mod, State)), + Reply = try_dispatch(Msg, Mod, State), handle_common_reply(Reply, Parent, Name, Msg, Mod, State, Debug). handle_common_reply(Reply, Parent, Name, Msg, Mod, State) -> case Reply of - {noreply, NState} -> + {ok, {noreply, NState}} -> loop(Parent, Name, NState, Mod, infinity, []); - {noreply, NState, Time1} -> + {ok, {noreply, NState, Time1}} -> loop(Parent, Name, NState, Mod, Time1, []); - {stop, Reason, NState} -> + {ok, {stop, Reason, NState}} -> terminate(Reason, Name, Msg, Mod, NState, []); - {'EXIT', What} -> - terminate(What, Name, Msg, Mod, State, []); - _ -> - terminate({bad_return_value, Reply}, Name, Msg, Mod, State, []) + {'EXIT', ExitReason, ReportReason} -> + terminate(ExitReason, ReportReason, Name, Msg, Mod, State, []); + {ok, BadReply} -> + terminate({bad_return_value, BadReply}, Name, Msg, Mod, State, []) end. handle_common_reply(Reply, Parent, Name, Msg, Mod, State, Debug) -> case Reply of - {noreply, NState} -> + {ok, {noreply, NState}} -> Debug1 = sys:handle_debug(Debug, fun print_event/3, Name, {noreply, NState}), loop(Parent, Name, NState, Mod, infinity, Debug1); - {noreply, NState, Time1} -> + {ok, {noreply, NState, Time1}} -> Debug1 = sys:handle_debug(Debug, fun print_event/3, Name, {noreply, NState}), loop(Parent, Name, NState, Mod, Time1, Debug1); - {stop, Reason, NState} -> + {ok, {stop, Reason, NState}} -> terminate(Reason, Name, Msg, Mod, NState, Debug); - {'EXIT', What} -> - terminate(What, Name, Msg, Mod, State, Debug); - _ -> - terminate({bad_return_value, Reply}, Name, Msg, Mod, State, Debug) + {'EXIT', ExitReason, ReportReason} -> + terminate(ExitReason, ReportReason, Name, Msg, Mod, State, Debug); + {ok, BadReply} -> + terminate({bad_return_value, BadReply}, Name, Msg, Mod, State, Debug) end. reply(Name, {To, Tag}, Reply, State, Debug) -> @@ -718,13 +779,16 @@ print_event(Dev, Event, Name) -> %%% --------------------------------------------------- terminate(Reason, Name, Msg, Mod, State, Debug) -> - case catch Mod:terminate(Reason, State) of - {'EXIT', R} -> + terminate(Reason, Reason, Name, Msg, Mod, State, Debug). +terminate(ExitReason, ReportReason, Name, Msg, Mod, State, Debug) -> + Reply = try_terminate(Mod, ExitReason, State), + case Reply of + {'EXIT', ExitReason1, ReportReason1} -> FmtState = format_status(terminate, Mod, get(), State), - error_info(R, Name, Msg, FmtState, Debug), - exit(R); + error_info(ReportReason1, Name, Msg, FmtState, Debug), + exit(ExitReason1); _ -> - case Reason of + case ExitReason of normal -> exit(normal); shutdown -> @@ -733,8 +797,8 @@ terminate(Reason, Name, Msg, Mod, State, Debug) -> exit(Shutdown); _ -> FmtState = format_status(terminate, Mod, get(), State), - error_info(Reason, Name, Msg, FmtState, Debug), - exit(Reason) + error_info(ReportReason, Name, Msg, FmtState, Debug), + exit(ExitReason) end end. diff --git a/lib/stdlib/test/gen_server_SUITE.erl b/lib/stdlib/test/gen_server_SUITE.erl index 42694d8b5d..0f03fda30a 100644 --- a/lib/stdlib/test/gen_server_SUITE.erl +++ b/lib/stdlib/test/gen_server_SUITE.erl @@ -275,7 +275,9 @@ crash(Config) when is_list(Config) -> receive {error,_GroupLeader4,{Pid4, "** Generic server"++_, - [Pid4,crash,{formatted, state4},crashed]}} -> + [Pid4,crash,{formatted, state4}, + {crashed,[{?MODULE,handle_call,3,_} + |_Stacktrace]}]}} -> ok; Other4a -> ?line io:format("Unexpected: ~p", [Other4a]), @@ -1026,7 +1028,9 @@ error_format_status(Config) when is_list(Config) -> receive {error,_GroupLeader,{Pid, "** Generic server"++_, - [Pid,crash,{formatted, State},crashed]}} -> + [Pid,crash,{formatted, State}, + {crashed,[{?MODULE,handle_call,3,_} + |_Stacktrace]}]}} -> ok; Other -> ?line io:format("Unexpected: ~p", [Other]), @@ -1048,7 +1052,9 @@ terminate_crash_format(Config) when is_list(Config) -> receive {error,_GroupLeader,{Pid, "** Generic server"++_, - [Pid,stop, {formatted, State},{crash, terminate}]}} -> + [Pid,stop, {formatted, State}, + {{crash, terminate},[{?MODULE,terminate,2,_} + |_Stacktrace]}]}} -> ok; Other -> io:format("Unexpected: ~p", [Other]), -- cgit v1.2.3