Merge branch 'egil/20/erts/signal-service/OTP-14186'

* egil/20/erts/signal-service/OTP-14186:
  kernel: Document signal server
  erts: Use os module instead of erts_internal for set_signal/2
  erts: Do not handle SIGILL
  erts: Fix thread suspend in crashdump
  erts: Do not enable SIGINT
  erts: Use generic signal handler
  erts: Add OS signal tests
  erts: Handle SIGUSR1 via signal service instead
  erts: Handle SIGTERM via signal service instead
  kernel: Add gen_event signal server and default handler
  erts: Add SIGHUP signal handler
  erts: Remove whitespace errors

Conflicts:
	erts/emulator/beam/bif.tab

4 files changed, 427 insertions, 0 deletions

diff --git a/erts/emulator/test/Makefile b/erts/emulator/test/Makefile
index 7c9927c4f3..6f9827002a 100644
--- a/erts/emulator/test/Makefile
+++ b/erts/emulator/test/Makefile
@@ -86,6 +86,7 @@ MODULES= \
 	num_bif_SUITE \
 	message_queue_data_SUITE \
 	op_SUITE \
+	os_signal_SUITE \
 	port_SUITE \
 	port_bif_SUITE \
 	process_SUITE \
diff --git a/erts/emulator/test/os_signal_SUITE.erl b/erts/emulator/test/os_signal_SUITE.erl
new file mode 100644
index 0000000000..9aa49a453e
--- /dev/null
+++ b/erts/emulator/test/os_signal_SUITE.erl
@@ -0,0 +1,354 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%% 
+%% 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
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% 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.
+%% 
+%% %CopyrightEnd%
+%%
+
+%%
+%% File:    os_signal_SUITE.erl
+%% Author:  Björn-Egil Dahlberg
+%% Created: 2017-01-13
+%%
+
+-module(os_signal_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+-export([all/0, suite/0]).
+-export([init_per_testcase/2, end_per_testcase/2]).
+-export([init_per_suite/1, end_per_suite/1]).
+
+-export([set_alarm/1, fork/0, get_exit_code/1]).
+
+% Test cases
+-export([set_unset/1,
+         t_sighup/1,
+         t_sigusr1/1,
+         t_sigusr2/1,
+         t_sigterm/1,
+         t_sigalrm/1,
+         t_sigchld/1,
+         t_sigchld_fork/1]).
+
+-define(signal_server, erl_signal_server).
+
+suite() ->
+    [{ct_hooks,[ts_install_cth]},
+     {timetrap, {minutes, 2}}].
+
+all() ->
+    case os:type() of
+        {win32, _} -> [];
+        _ -> [set_unset,
+              t_sighup,
+              t_sigusr1,
+              t_sigusr2,
+              t_sigterm,
+              t_sigalrm,
+              t_sigchld,
+              t_sigchld_fork]
+    end.
+
+init_per_testcase(Func, Config) when is_atom(Func), is_list(Config) ->
+    Pid = erlang:whereis(?signal_server),
+    true = erlang:unregister(?signal_server),
+    [{signal_server, Pid}|Config].
+
+end_per_testcase(_Func, Config) ->
+    case proplists:get_value(signal_server, Config) of
+        undefined -> ok;
+        Pid ->
+            true = erlang:register(?signal_server, Pid),
+            ok
+    end.
+
+init_per_suite(Config) ->
+    load_nif(Config),
+    Config.
+
+end_per_suite(_Config) ->
+    ok.
+
+%% tests
+
+set_unset(_Config) ->
+    Signals = [sighup, %sigint,
+               sigquit, %sigill,
+               sigabrt,
+               sigalrm, sigterm,
+               sigusr1, sigusr2,
+               sigchld,
+               sigstop, sigtstp],
+    F1 = fun(Sig) -> ok = os:set_signal(Sig,handle) end,
+    F2 = fun(Sig) -> ok = os:set_signal(Sig,default) end,
+    F3 = fun(Sig) -> ok = os:set_signal(Sig,ignore) end,
+    %% set handle
+    ok = lists:foreach(F1, Signals),
+    %% set ignore
+    ok = lists:foreach(F2, Signals),
+    %% set default
+    ok = lists:foreach(F3, Signals),
+    ok.
+
+t_sighup(_Config) ->
+    Pid1 = setup_service(),
+    OsPid = os:getpid(),
+    os:set_signal(sighup, handle),
+    ok = kill("HUP", OsPid),
+    ok = kill("HUP", OsPid),
+    ok = kill("HUP", OsPid),
+    Msgs1 = fetch_msgs(Pid1),
+    io:format("Msgs1: ~p~n", [Msgs1]),
+    [{notify,sighup},
+     {notify,sighup},
+     {notify,sighup}] = Msgs1,
+    %% no proc
+    ok = kill("HUP", OsPid),
+    ok = kill("HUP", OsPid),
+    ok = kill("HUP", OsPid),
+    %% ignore
+    Pid2 = setup_service(),
+    os:set_signal(sighup, ignore),
+    ok = kill("HUP", OsPid),
+    ok = kill("HUP", OsPid),
+    ok = kill("HUP", OsPid),
+    Msgs2 = fetch_msgs(Pid2),
+    io:format("Msgs2: ~p~n", [Msgs2]),
+    [] = Msgs2,
+    %% reset to handle (it's the default)
+    os:set_signal(sighup, handle),
+    ok.
+
+t_sigusr1(_Config) ->
+    Pid1 = setup_service(),
+    OsPid = os:getpid(),
+    os:set_signal(sigusr1, handle),
+    ok = kill("USR1", OsPid),
+    ok = kill("USR1", OsPid),
+    ok = kill("USR1", OsPid),
+    Msgs1 = fetch_msgs(Pid1),
+    io:format("Msgs1: ~p~n", [Msgs1]),
+    [{notify,sigusr1},
+     {notify,sigusr1},
+     {notify,sigusr1}] = Msgs1,
+    %% no proc
+    ok = kill("USR1", OsPid),
+    ok = kill("USR1", OsPid),
+    ok = kill("USR1", OsPid),
+    %% ignore
+    Pid2 = setup_service(),
+    os:set_signal(sigusr1, ignore),
+    ok = kill("USR1", OsPid),
+    ok = kill("USR1", OsPid),
+    ok = kill("USR1", OsPid),
+    Msgs2 = fetch_msgs(Pid2),
+    io:format("Msgs2: ~p~n", [Msgs2]),
+    [] = Msgs2,
+    %% reset to ignore (it's the default)
+    os:set_signal(sigusr1, handle),
+    ok.
+
+t_sigusr2(_Config) ->
+    Pid1 = setup_service(),
+    OsPid = os:getpid(),
+    os:set_signal(sigusr2, handle),
+    ok = kill("USR2", OsPid),
+    ok = kill("USR2", OsPid),
+    ok = kill("USR2", OsPid),
+    Msgs1 = fetch_msgs(Pid1),
+    io:format("Msgs1: ~p~n", [Msgs1]),
+    [{notify,sigusr2},
+     {notify,sigusr2},
+     {notify,sigusr2}] = Msgs1,
+    %% no proc
+    ok = kill("USR2", OsPid),
+    ok = kill("USR2", OsPid),
+    ok = kill("USR2", OsPid),
+    %% ignore
+    Pid2 = setup_service(),
+    os:set_signal(sigusr2, ignore),
+    ok = kill("USR2", OsPid),
+    ok = kill("USR2", OsPid),
+    ok = kill("USR2", OsPid),
+    Msgs2 = fetch_msgs(Pid2),
+    io:format("Msgs2: ~p~n", [Msgs2]),
+    [] = Msgs2,
+    %% reset to ignore (it's the default)
+    os:set_signal(sigusr2, ignore),
+    ok.
+
+t_sigterm(_Config) ->
+    Pid1 = setup_service(),
+    OsPid = os:getpid(),
+    os:set_signal(sigterm, handle),
+    ok = kill("TERM", OsPid),
+    ok = kill("TERM", OsPid),
+    ok = kill("TERM", OsPid),
+    Msgs1 = fetch_msgs(Pid1),
+    io:format("Msgs1: ~p~n", [Msgs1]),
+    [{notify,sigterm},
+     {notify,sigterm},
+     {notify,sigterm}] = Msgs1,
+    %% no proc
+    ok = kill("TERM", OsPid),
+    ok = kill("TERM", OsPid),
+    ok = kill("TERM", OsPid),
+    %% ignore
+    Pid2 = setup_service(),
+    os:set_signal(sigterm, ignore),
+    ok = kill("TERM", OsPid),
+    ok = kill("TERM", OsPid),
+    ok = kill("TERM", OsPid),
+    Msgs2 = fetch_msgs(Pid2),
+    io:format("Msgs2: ~p~n", [Msgs2]),
+    [] = Msgs2,
+    %% reset to handle (it's the default)
+    os:set_signal(sigterm, handle),
+    ok.
+
+t_sigchld(_Config) ->
+    Pid1 = setup_service(),
+    OsPid = os:getpid(),
+    os:set_signal(sigchld, handle),
+    ok = kill("CHLD", OsPid),
+    ok = kill("CHLD", OsPid),
+    ok = kill("CHLD", OsPid),
+    Msgs1 = fetch_msgs(Pid1),
+    io:format("Msgs1: ~p~n", [Msgs1]),
+    [{notify,sigchld},
+     {notify,sigchld},
+     {notify,sigchld}] = Msgs1,
+    %% no proc
+    ok = kill("CHLD", OsPid),
+    ok = kill("CHLD", OsPid),
+    ok = kill("CHLD", OsPid),
+    %% ignore
+    Pid2 = setup_service(),
+    os:set_signal(sigchld, ignore),
+    ok = kill("CHLD", OsPid),
+    ok = kill("CHLD", OsPid),
+    ok = kill("CHLD", OsPid),
+    Msgs2 = fetch_msgs(Pid2),
+    io:format("Msgs2: ~p~n", [Msgs2]),
+    [] = Msgs2,
+    %% reset to handle (it's the default)
+    os:set_signal(sigchld, ignore),
+    ok.
+
+
+t_sigalrm(_Config) ->
+    Pid1 = setup_service(),
+    ok = os:set_signal(sigalrm, handle),
+    ok = os_signal_SUITE:set_alarm(1),
+    receive after 3000 -> ok end,
+    Msgs1 = fetch_msgs(Pid1),
+    [{notify,sigalrm}] = Msgs1,
+    io:format("Msgs1: ~p~n", [Msgs1]),
+    os:set_signal(sigalrm, ignore),
+    Pid2 = setup_service(),
+    ok = os_signal_SUITE:set_alarm(1),
+    receive after 3000 -> ok end,
+    Msgs2 = fetch_msgs(Pid2),
+    [] = Msgs2,
+    io:format("Msgs2: ~p~n", [Msgs2]),
+    Pid3 = setup_service(),
+    os:set_signal(sigalrm, handle),
+    ok = os_signal_SUITE:set_alarm(1),
+    receive after 3000 -> ok end,
+    Msgs3 = fetch_msgs(Pid3),
+    [{notify,sigalrm}] = Msgs3,
+    io:format("Msgs3: ~p~n", [Msgs3]),
+    os:set_signal(sigalrm, ignore),
+    ok.
+
+t_sigchld_fork(_Config) ->
+    Pid1 = setup_service(),
+    ok = os:set_signal(sigchld, handle),
+    {ok,OsPid} = os_signal_SUITE:fork(),
+    receive after 3000 -> ok end,
+    Msgs1 = fetch_msgs(Pid1),
+    io:format("Msgs1: ~p~n", [Msgs1]),
+    [{notify,sigchld}] = Msgs1,
+    {ok,Status} = os_signal_SUITE:get_exit_code(OsPid),
+    io:format("exit status from ~w : ~w~n", [OsPid,Status]),
+    42 = Status,
+    %% reset to ignore (it's the default)
+    os:set_signal(sigchld, ignore),
+    ok.
+
+
+%% nif stubs
+
+set_alarm(_Secs) -> no.
+fork() -> no.
+get_exit_code(_OsPid) -> no.
+
+%% aux
+
+setup_service() ->
+    Pid = spawn_link(fun msgs/0),
+    true = erlang:register(?signal_server, Pid),
+    Pid.
+
+msgs() ->
+    msgs([]).
+msgs(Ms) ->
+    receive
+        {Pid, fetch_msgs} -> Pid ! {self(), lists:reverse(Ms)};
+        Msg ->
+            msgs([Msg|Ms])
+    end.
+
+fetch_msgs(Pid) ->
+    Pid ! {self(), fetch_msgs},
+    receive {Pid, Msgs} -> Msgs end.
+
+kill(Signal, Pid) ->
+    {0,_} = run("kill", ["-s", Signal, Pid]),
+    receive after 200 -> ok end,
+    ok.
+
+load_nif(Config) ->
+    Path = proplists:get_value(data_dir, Config),
+    ok = erlang:load_nif(filename:join(Path,"os_signal_nif"), 0).
+
+run(Program0, Args) -> run(".", Program0, Args).
+run(Cwd, Program0, Args) when is_list(Cwd) ->
+    Program = case os:find_executable(Program0) of
+                  Path when is_list(Path) ->
+                      Path;
+                  false ->
+                      exit(no)
+              end,
+    Options = [{args,Args},binary,exit_status,stderr_to_stdout,
+               {line,4096}, {cd, Cwd}],
+    try open_port({spawn_executable,Program}, Options) of
+        Port ->
+            run_loop(Port, [])
+    catch
+        error:_ ->
+                      exit(no)
+    end.
+
+run_loop(Port, Output) ->
+    receive
+        {Port,{exit_status,Status}} ->
+            {Status,lists:reverse(Output)};
+        {Port,{data,{eol,Bin}}} ->
+            run_loop(Port, [Bin|Output]);
+        _Msg ->
+            run_loop(Port, Output)
+    end.
diff --git a/erts/emulator/test/os_signal_SUITE_data/Makefile.src b/erts/emulator/test/os_signal_SUITE_data/Makefile.src
new file mode 100644
index 0000000000..a7f5cdbba5
--- /dev/null
+++ b/erts/emulator/test/os_signal_SUITE_data/Makefile.src
@@ -0,0 +1,6 @@
+
+NIF_LIBS = os_signal_nif@dll@
+
+all: $(NIF_LIBS)
+
+@SHLIB_RULES@
diff --git a/erts/emulator/test/os_signal_SUITE_data/os_signal_nif.c b/erts/emulator/test/os_signal_SUITE_data/os_signal_nif.c
new file mode 100644
index 0000000000..78e1348383
--- /dev/null
+++ b/erts/emulator/test/os_signal_SUITE_data/os_signal_nif.c
@@ -0,0 +1,66 @@
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+
+#include <erl_nif.h>
+
+static int load(ErlNifEnv* env, void** priv_data, ERL_NIF_TERM load_info)
+{
+    return 0;
+}
+
+static ERL_NIF_TERM set_alarm(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{
+    int t;
+    if (!enif_get_int(env, argv[0], &t)) {
+        return enif_make_badarg(env);
+    }
+
+    alarm(t);
+
+    return enif_make_atom(env, "ok");
+}
+
+static ERL_NIF_TERM fork_0(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{
+    pid_t pid;
+
+    pid = fork();
+
+    if (pid == 0) {
+        /* child */
+        exit(42);
+    }
+
+    return enif_make_tuple(env, 2,
+            enif_make_atom(env, "ok"),
+            enif_make_int(env, (int)pid));
+}
+
+static ERL_NIF_TERM get_exit_code(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{
+    int x;
+    pid_t pid;
+    if (!enif_get_int(env, argv[0], &x)) {
+        return enif_make_badarg(env);
+    }
+
+    pid = (pid_t) x;
+
+    waitpid(pid, &x, 0);
+
+    return enif_make_tuple(env, 2,
+            enif_make_atom(env, "ok"),
+            enif_make_int(env, WEXITSTATUS(x)));
+}
+
+
+static ErlNifFunc nif_funcs[] =
+{
+    {"set_alarm", 1, set_alarm},
+    {"fork", 0, fork_0},
+    {"get_exit_code", 1, get_exit_code}
+};
+
+ERL_NIF_INIT(os_signal_SUITE,nif_funcs,load,NULL,NULL,NULL)