From 95ed86fc9893460751c5141ff872bdc13814a273 Mon Sep 17 00:00:00 2001 From: Geoff Cant Date: Sat, 12 Jun 2010 16:49:54 -0700 Subject: Fix format_status bug for unregistered gen_event processes Port the gen_fsm code for format_status to gen_event in order to prevent a lists:concat([...,pid()]) crash when calling sys:get_status/1 on an unregistered gen_event process. Refactor format_status header code from gen_* behaviours to module gen. Extend the format_status tests in gen_event_SUITE to cover format_status bugs with anonymous gen_event processes. --- lib/stdlib/src/gen.erl | 9 +++++++++ lib/stdlib/src/gen_event.erl | 3 ++- lib/stdlib/src/gen_fsm.erl | 11 ++--------- lib/stdlib/src/gen_server.erl | 11 ++--------- lib/stdlib/test/gen_event_SUITE.erl | 22 ++++++++++++++++++++-- 5 files changed, 35 insertions(+), 21 deletions(-) diff --git a/lib/stdlib/src/gen.erl b/lib/stdlib/src/gen.erl index 43df6f621d..574146b1cd 100644 --- a/lib/stdlib/src/gen.erl +++ b/lib/stdlib/src/gen.erl @@ -29,6 +29,8 @@ -export([init_it/6, init_it/7]). +-export([format_status_header/2]). + -define(default_timeout, 5000). %%----------------------------------------------------------------- @@ -315,3 +317,10 @@ debug_options(Opts) -> {ok, Options} -> sys:debug_options(Options); _ -> [] end. + +format_status_header(TagLine, Pid) when is_pid(Pid) -> + lists:concat([TagLine, " ", pid_to_list(Pid)]); +format_status_header(TagLine, RegName) when is_atom(RegName) -> + lists:concat([TagLine, " ", RegName]); +format_status_header(TagLine, Name) -> + {TagLine, Name}. diff --git a/lib/stdlib/src/gen_event.erl b/lib/stdlib/src/gen_event.erl index b1e9e3a02f..b00910771f 100644 --- a/lib/stdlib/src/gen_event.erl +++ b/lib/stdlib/src/gen_event.erl @@ -724,7 +724,8 @@ get_modules(MSL) -> %%----------------------------------------------------------------- format_status(Opt, StatusData) -> [PDict, SysState, Parent, _Debug, [ServerName, MSL, _Hib]] = StatusData, - Header = lists:concat(["Status for event handler ", ServerName]), + Header = gen:format_status_header("Status for event handler", + ServerName), FmtMSL = [case erlang:function_exported(Mod, format_status, 2) of true -> Args = [PDict, State], diff --git a/lib/stdlib/src/gen_fsm.erl b/lib/stdlib/src/gen_fsm.erl index 7d9960b912..f2f1365d3d 100644 --- a/lib/stdlib/src/gen_fsm.erl +++ b/lib/stdlib/src/gen_fsm.erl @@ -614,15 +614,8 @@ get_msg(Msg) -> Msg. format_status(Opt, StatusData) -> [PDict, SysState, Parent, Debug, [Name, StateName, StateData, Mod, _Time]] = StatusData, - StatusHdr = "Status for state machine", - Header = if - is_pid(Name) -> - lists:concat([StatusHdr, " ", pid_to_list(Name)]); - is_atom(Name); is_list(Name) -> - lists:concat([StatusHdr, " ", Name]); - true -> - {StatusHdr, Name} - end, + Header = gen:format_status_header("Status for state machine", + Name), Log = sys:get_debug(log, Debug, []), DefaultStatus = [{data, [{"StateData", StateData}]}], Specfic = diff --git a/lib/stdlib/src/gen_server.erl b/lib/stdlib/src/gen_server.erl index ac81df9cab..09d94a9c40 100644 --- a/lib/stdlib/src/gen_server.erl +++ b/lib/stdlib/src/gen_server.erl @@ -840,15 +840,8 @@ name_to_pid(Name) -> %%----------------------------------------------------------------- format_status(Opt, StatusData) -> [PDict, SysState, Parent, Debug, [Name, State, Mod, _Time]] = StatusData, - StatusHdr = "Status for generic server", - Header = if - is_pid(Name) -> - lists:concat([StatusHdr, " ", pid_to_list(Name)]); - is_atom(Name); is_list(Name) -> - lists:concat([StatusHdr, " ", Name]); - true -> - {StatusHdr, Name} - end, + Header = gen:format_status_header("Status for generic server", + Name), Log = sys:get_debug(log, Debug, []), DefaultStatus = [{data, [{"State", State}]}], Specfic = diff --git a/lib/stdlib/test/gen_event_SUITE.erl b/lib/stdlib/test/gen_event_SUITE.erl index 4f7de451e3..4c6466d860 100644 --- a/lib/stdlib/test/gen_event_SUITE.erl +++ b/lib/stdlib/test/gen_event_SUITE.erl @@ -24,10 +24,12 @@ -export([start/1, test_all/1, add_handler/1, add_sup_handler/1, delete_handler/1, swap_handler/1, swap_sup_handler/1, notify/1, sync_notify/1, call/1, info/1, hibernate/1, - call_format_status/1, error_format_status/1]). + call_format_status/1, call_format_status_anon/1, + error_format_status/1]). all(suite) -> {req, [stdlib], [start, test_all, hibernate, - call_format_status, error_format_status]}. + call_format_status, call_format_status_anon, + error_format_status]}. %% -------------------------------------- %% Start an event manager. @@ -868,6 +870,22 @@ call_format_status(Config) when is_list(Config) -> ?line {"Installed handlers", [{_,dummy1_h,_,FmtState,_}]} = HandlerInfo2, ok. +call_format_status_anon(suite) -> + []; +call_format_status_anon(doc) -> + ["Test that sys:get_status/1,2 calls format_status/2 for anonymous gen_event processes"]; +call_format_status_anon(Config) when is_list(Config) -> + ?line {ok, Pid} = gen_event:start(), + %% The 'Name' of the gen_event process will be a pid() here, so + %% the next line will crash if format_status can't string-ify pids. + ?line Status1 = sys:get_status(Pid), + ?line ok = gen_event:stop(Pid), + Header = "Status for event handler " ++ pid_to_list(Pid), + ?line {status, Pid, _, [_, _, Pid, [], Data1]} = Status1, + ?line Header = proplists:get_value(header, Data1), + ok. + + error_format_status(suite) -> []; error_format_status(doc) -> -- cgit v1.2.3