From a7b52ad679e6a58a9351a26e198eee70067b000f Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn-Egil=20Dahlberg?= Date: Mon, 13 Apr 2015 18:47:06 +0200 Subject: kernel: Add gen_event signal server and default handler --- lib/kernel/src/Makefile | 1 + lib/kernel/src/erl_signal_handler.erl | 47 +++++++++++++++++++++++++++++++++++ lib/kernel/src/kernel.app.src | 1 + lib/kernel/src/kernel.erl | 13 +++++++++- 4 files changed, 61 insertions(+), 1 deletion(-) create mode 100644 lib/kernel/src/erl_signal_handler.erl (limited to 'lib/kernel') diff --git a/lib/kernel/src/Makefile b/lib/kernel/src/Makefile index 2b72f78dcf..2a89faaf13 100644 --- a/lib/kernel/src/Makefile +++ b/lib/kernel/src/Makefile @@ -71,6 +71,7 @@ MODULES = \ erl_distribution \ erl_epmd \ erl_reply \ + erl_signal_handler \ erts_debug \ error_handler \ error_logger \ diff --git a/lib/kernel/src/erl_signal_handler.erl b/lib/kernel/src/erl_signal_handler.erl new file mode 100644 index 0000000000..6bd8f992a7 --- /dev/null +++ b/lib/kernel/src/erl_signal_handler.erl @@ -0,0 +1,47 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 1996-2013. All Rights Reserved. +%% +%% The contents of this file are subject to the Erlang Public License, +%% Version 1.1, (the "License"); you may not use this file except in +%% compliance with the License. You should have received a copy of the +%% Erlang Public License along with this software. If not, it can be +%% retrieved online at http://www.erlang.org/. +%% +%% Software distributed under the License is distributed on an "AS IS" +%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See +%% the License for the specific language governing rights and limitations +%% under the License. +%% +%% %CopyrightEnd% +%% + +-module(erl_signal_handler). +-behaviour(gen_event). +-export([init/1, format_status/2, + handle_event/2, handle_call/2, handle_info/2, + terminate/2, code_change/3]). + +-record(state,{}). + +init(_Args) -> + {ok, #state{}}. + +handle_event(_SignalMsg, S) -> + {ok, S}. + +handle_info(_Info, S) -> + {ok, S}. + +handle_call(_Request, S) -> + {ok, ok, S}. + +format_status(_Opt, [_Pdict,_S]) -> + ok. + +code_change(_OldVsn, S, _Extra) -> + {ok, S}. + +terminate(_Args, _S) -> + ok. diff --git a/lib/kernel/src/kernel.app.src b/lib/kernel/src/kernel.app.src index 4d08a55c7c..25e4ddd95c 100644 --- a/lib/kernel/src/kernel.app.src +++ b/lib/kernel/src/kernel.app.src @@ -34,6 +34,7 @@ erl_boot_server, erl_distribution, erl_reply, + erl_signal_handler, error_handler, error_logger, file, diff --git a/lib/kernel/src/kernel.erl b/lib/kernel/src/kernel.erl index 3d0ef81318..59eca242b1 100644 --- a/lib/kernel/src/kernel.erl +++ b/lib/kernel/src/kernel.erl @@ -32,6 +32,14 @@ start(_, []) -> case supervisor:start_link({local, kernel_sup}, kernel, []) of {ok, Pid} -> + %% add signal handler + case whereis(erl_signal_server) of + %% in case of minimal mode + undefined -> ok; + _ -> + ok = gen_event:add_handler(erl_signal_server, erl_signal_handler, []) + end, + %% add error handler Type = get_error_logger_type(), case error_logger:swap_handler(Type) of ok -> {ok, Pid, []}; @@ -131,6 +139,9 @@ init([]) -> permanent, 2000, worker, [inet_db]}, NetSup = {net_sup, {erl_distribution, start_link, []}, permanent, infinity, supervisor,[erl_distribution]}, + SigSrv = #{id => erl_signal_server, + start => {gen_event, start_link, [{local, erl_signal_server}]}, + type => worker, restart => permanent, shutdown => 2000, modules => dynamic}, DistAC = start_dist_ac(), Timer = start_timer(), @@ -141,7 +152,7 @@ init([]) -> permanent, infinity, supervisor, [?MODULE]}, {ok, {SupFlags, [Code, Rpc, Global, InetDb | DistAC] ++ - [NetSup, Glo_grp, File, + [NetSup, Glo_grp, File, SigSrv, StdError, User, Config, SafeSupervisor] ++ Timer}} end; init(safe) -> -- cgit v1.2.3 From 40c82769def0cfa59e75669ff1c6fc4abcecd764 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn-Egil=20Dahlberg?= Date: Thu, 15 Dec 2016 18:07:13 +0100 Subject: erts: Handle SIGTERM via signal service instead --- lib/kernel/src/erl_signal_handler.erl | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'lib/kernel') diff --git a/lib/kernel/src/erl_signal_handler.erl b/lib/kernel/src/erl_signal_handler.erl index 6bd8f992a7..04130eac66 100644 --- a/lib/kernel/src/erl_signal_handler.erl +++ b/lib/kernel/src/erl_signal_handler.erl @@ -28,6 +28,10 @@ init(_Args) -> {ok, #state{}}. +handle_event(sigterm, S) -> + error_logger:info_msg("SIGTERM received - shutting down~n"), + ok = init:stop(), + {ok, S}; handle_event(_SignalMsg, S) -> {ok, S}. -- cgit v1.2.3 From 2d3bf84d8167b50728b0a5411a4e2dfa71d52c10 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn-Egil=20Dahlberg?= Date: Fri, 16 Dec 2016 12:24:13 +0100 Subject: erts: Handle SIGUSR1 via signal service instead --- lib/kernel/src/erl_signal_handler.erl | 3 +++ 1 file changed, 3 insertions(+) (limited to 'lib/kernel') diff --git a/lib/kernel/src/erl_signal_handler.erl b/lib/kernel/src/erl_signal_handler.erl index 04130eac66..43cc307ffd 100644 --- a/lib/kernel/src/erl_signal_handler.erl +++ b/lib/kernel/src/erl_signal_handler.erl @@ -28,6 +28,9 @@ init(_Args) -> {ok, #state{}}. +handle_event(sigusr1, S) -> + erlang:halt("Received SIGUSR1"), + {ok, S}; handle_event(sigterm, S) -> error_logger:info_msg("SIGTERM received - shutting down~n"), ok = init:stop(), -- cgit v1.2.3 From 120f04387ade07ef5b8b6d20a04de7d21e0c40ca Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn-Egil=20Dahlberg?= Date: Thu, 5 Jan 2017 17:17:52 +0100 Subject: erts: Use generic signal handler --- lib/kernel/src/erl_signal_handler.erl | 3 +++ 1 file changed, 3 insertions(+) (limited to 'lib/kernel') diff --git a/lib/kernel/src/erl_signal_handler.erl b/lib/kernel/src/erl_signal_handler.erl index 43cc307ffd..8f924d2adc 100644 --- a/lib/kernel/src/erl_signal_handler.erl +++ b/lib/kernel/src/erl_signal_handler.erl @@ -31,6 +31,9 @@ init(_Args) -> handle_event(sigusr1, S) -> erlang:halt("Received SIGUSR1"), {ok, S}; +handle_event(sigquit, S) -> + erlang:halt(), + {ok, S}; handle_event(sigterm, S) -> error_logger:info_msg("SIGTERM received - shutting down~n"), ok = init:stop(), -- cgit v1.2.3 From d4bd17da9759af54227891a90d9fb83d5bfe6d7e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn-Egil=20Dahlberg?= Date: Tue, 24 Jan 2017 10:59:30 +0100 Subject: erts: Use os module instead of erts_internal for set_signal/2 * Add specs * Change return signature to 'ok' instead of 'true' --- lib/kernel/src/os.erl | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'lib/kernel') diff --git a/lib/kernel/src/os.erl b/lib/kernel/src/os.erl index f8519d3a5e..c3ffcb3f70 100644 --- a/lib/kernel/src/os.erl +++ b/lib/kernel/src/os.erl @@ -29,7 +29,7 @@ -export([getenv/0, getenv/1, getenv/2, getpid/0, perf_counter/0, perf_counter/1, - putenv/2, system_time/0, system_time/1, + putenv/2, set_signal/2, system_time/0, system_time/1, timestamp/0, unsetenv/1]). -spec getenv() -> [string()]. @@ -104,6 +104,15 @@ timestamp() -> unsetenv(_) -> erlang:nif_error(undef). +-spec set_signal(Signal, Option) -> 'ok' when + Signal :: 'sighup' | 'sigquit' | 'sigabrt' | 'sigalrm' | + 'sigterm' | 'sigusr1' | 'sigusr2' | 'sigchld' | + 'sigstop' | 'sigtstp', + Option :: 'default' | 'handle' | 'ignore'. + +set_signal(_Signal, _Option) -> + erlang:nif_error(undef). + %%% End of BIFs -spec type() -> {Osfamily, Osname} when -- cgit v1.2.3 From 1409b6ae110f60c410e83d1923dd59ae3659a887 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn-Egil=20Dahlberg?= Date: Wed, 1 Feb 2017 16:44:50 +0100 Subject: kernel: Document signal server --- lib/kernel/doc/src/kernel_app.xml | 59 +++++++++++++++++++++++++++++++++++++-- lib/kernel/doc/src/os.xml | 31 ++++++++++++++++++-- 2 files changed, 84 insertions(+), 6 deletions(-) (limited to 'lib/kernel') diff --git a/lib/kernel/doc/src/kernel_app.xml b/lib/kernel/doc/src/kernel_app.xml index df681a505f..c581fa9d1e 100644 --- a/lib/kernel/doc/src/kernel_app.xml +++ b/lib/kernel/doc/src/kernel_app.xml @@ -11,7 +11,7 @@ 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 @@ -19,7 +19,7 @@ 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. - + kernel @@ -57,6 +57,60 @@ error_logger(3).

+
+ OS Signal Event Handler +

Asynchronous OS signals may be subscribed to via the Kernel applications event manager + (see OTP Design Principles and + gen_event(3)) registered as erl_signal_server. + A default signal handler is installed which handles the following signals:

+ + sigusr1 +

The default handler will halt Erlang and produce a crashdump + with slogan "Received SIGUSR1". + This is equivalent to calling erlang:halt("Received SIGUSR1"). +

+ + sigquit +

The default handler will halt Erlang immediately. + This is equivalent to calling erlang:halt(). +

+ + sigterm +

The default handler will terminate Erlang normally. + This is equivalent to calling init:stop(). +

+
+ +
+ Events +

Any event handler added to erl_signal_server must handle the following events.

+ + sighup +

Hangup detected on controlling terminal or death of controlling process

+ sigquit +

Quit from keyboard

+ sigabrt +

Abort signal from abort

+ sigalrm +

Timer signal from alarm

+ sigterm +

Termination signal

+ sigusr1 +

User-defined signal 1

+ sigusr2 +

User-defined signal 2

+ sigchld +

Child process stopped or terminated

+ sigstop +

Stop process

+ sigtstp +

Stop typed at terminal

+
+ +

Setting OS signals are described in os:set_signal/2.

+
+
+
Configuration

The following configuration parameters are defined for the Kernel @@ -405,4 +459,3 @@ MaxT = TickTime + TickTime / 4 timer(3)

- diff --git a/lib/kernel/doc/src/os.xml b/lib/kernel/doc/src/os.xml index 739ac35d2a..6ba69d12a3 100644 --- a/lib/kernel/doc/src/os.xml +++ b/lib/kernel/doc/src/os.xml @@ -11,7 +11,7 @@ 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 @@ -19,7 +19,7 @@ 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. - + os @@ -155,6 +155,32 @@ DirOut = os:cmd("dir"), % on Win32 platform + + + Enables or disables handling of OS signals. + +

Enables or disables OS signals.

+

Each signal my be set to one of the following options:

+ + ignore + + This signal will be ignored. + + + default + + This signal will use the default signal handler for the operating system. + + + handle + + This signal will notify erl_signal_server when it is received by + the Erlang runtime system. + + +
+
+ Current OS system time. @@ -296,4 +322,3 @@ calendar:now_to_universal_time(TS), - -- cgit v1.2.3