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%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1997-2009. 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(after_SUITE).
%% Tests receive after.
-include("test_server.hrl").
-export([all/1, t_after/1, receive_after/1, receive_after_big/1,
receive_after_errors/1, receive_var_zero/1, receive_zero/1,
multi_timeout/1, receive_after_32bit/1]).
-export([init_per_testcase/2, fin_per_testcase/2]).
%% Internal exports.
-export([timeout_g/0]).
all(suite) ->
[t_after, receive_after, receive_after_big, receive_after_errors,
receive_var_zero, receive_zero, multi_timeout, receive_after_32bit].
init_per_testcase(Func, Config) when is_atom(Func), is_list(Config) ->
Dog=?t:timetrap(?t:minutes(3)),
[{watchdog, Dog}|Config].
fin_per_testcase(_Func, Config) ->
Dog=?config(watchdog, Config),
?t:timetrap_cancel(Dog).
%% Tests for an old round-off error in 'receive after'."
t_after(Config) when is_list(Config) ->
?line spawn(fun frequent_process/0),
?line Period = test_server:minutes(1),
?line Before = erlang:now(),
receive
after Period ->
?line After = erlang:now(),
?line report(Period, Before, After)
end.
report(Period, Before, After) ->
?line Elapsed = (element(1, After)*1000000000
+element(2, After)*1000
+element(3, After) div 1000) -
(element(1,Before)*1000000000
+ element(2,Before)*1000 + element(3,Before) div 1000),
?line case Elapsed*100 / Period of
Percent when Percent > 100.10 ->
?line test_server:fail({too_inaccurate, Percent});
Percent when Percent < 100.0 ->
?line test_server:fail({too_early, Percent});
Percent ->
?line Comment = io_lib:format("Elapsed/expected: ~.2f %",
[Percent]),
{comment, lists:flatten(Comment)}
end.
frequent_process() ->
receive
after 100 ->
?line frequent_process()
end.
receive_after(doc) ->
"Test that 'receive after' works (doesn't hang). "
"The test takes 10 seconds to complete.";
receive_after(Config) when is_list(Config) ->
?line receive_after1(5000).
receive_after1(1) ->
?line io:format("Testing: receive after ~p~n", [1]),
?line receive after 1 -> ok end;
receive_after1(N) ->
?line io:format("Testing: receive after ~p~n", [N]),
?line receive after N -> receive_after1(N div 2) end.
receive_after_big(Config) when is_list(Config) ->
%% Test that 'receive after' with a 32 bit number works.
receive_after_big1(16#f7654321),
receive_after_big2().
receive_after_big1(Timeout) ->
Self = self(),
erlang:yield(),
spawn(fun() -> Self ! here_is_a_message end),
ok = receive
here_is_a_message ->
ok
after Timeout ->
%% We test that the timeout can be set,
%% not that an timeout occurs after the appropriate delay
%% (48 days, 56 minutes, 48 seconds)!
timeout
end.
receive_after_big2() ->
Self = self(),
erlang:yield(),
spawn(fun() -> Self ! here_is_a_message end),
ok = receive
here_is_a_message ->
ok
after 16#f7999977 ->
%% We only test that the timeout can be set.
timeout
end.
-define(TryAfter(Timeout),
{'EXIT',{timeout_value,_}} = (catch receive mission -> exit(impossible) after Timeout -> ok end),
{'EXIT',{timeout_value,_}} = (catch receive after Timeout -> ok end),
try_after(Timeout)).
%% Test error cases for 'receive after'.
receive_after_errors(Config) when is_list(Config) ->
?line ?TryAfter(-1),
?line ?TryAfter(0.0),
?line ?TryAfter(3.14),
?line ?TryAfter(16#100000000),
?line ?TryAfter(392347129847294724972398472984729847129874),
?line ?TryAfter(16#3fffffffffffffff),
?line ?TryAfter(16#ffffffffffffffff),
?line ?TryAfter(-16#100000000),
?line ?TryAfter(-3891278094774921784123987129848),
?line ?TryAfter(xxx),
ok.
try_after(Timeout) ->
{'EXIT',{timeout_value,_}} = (catch receive after Timeout -> ok end).
receive_var_zero(doc) -> "Test 'after Z', when Z == 0.";
receive_var_zero(Config) when is_list(Config) ->
self() ! x,
self() ! y,
Z = zero(),
timeout = receive
z -> ok
after Z -> timeout
end,
timeout = receive
after Z -> timeout
end,
self() ! w,
receive
x -> ok;
Other ->
?line ?t:fail({bad_message,Other})
end.
zero() -> 0.
%% Test 'after 0'.
receive_zero(Config) when is_list(Config) ->
self() ! x,
self() ! y,
timeout = receive
z -> ok
after 0 ->
timeout
end,
self() ! w,
timeout = receive
after 0 -> timeout
end,
receive
x -> ok;
Other ->
?line ?t:fail({bad_message,Other})
end.
multi_timeout(doc) ->
"Test for catching invalid assertion in erl_message.c (in queue_message)."
"This failed (dumped core) with debug-compiled emulator.";
multi_timeout(Config) when is_list(Config) ->
?line P = spawn(?MODULE, timeout_g, []),
?line P ! a,
?line P ! b,
?line receive
after 1000 -> ok
end,
?line P ! c,
?line receive
after 1000 -> ok
end,
?line P ! d,
ok.
timeout_g() ->
?line receive
a -> ok
end,
?line receive
after 100000 -> ok
end,
ok.
%% OTP-7493: Timeout for 32 bit numbers (such as 16#ffffFFFF) could
%% timeout at once.
receive_after_32bit(Config) when is_list(Config) ->
T = 16#ffffFFFF,
Pids = [spawn_link(fun() -> recv_after_32bit(I, T) end) ||
I <- lists:seq(1, 2048)],
%% Wait two seconds for any of the processes to timeout too early.
receive after 2000 -> ok end,
%% Kill the processes.
[begin unlink(Pid), exit(Pid, kill) end || Pid <- Pids],
ok.
recv_after_32bit(I, T) when I rem 2 =:= 0 ->
receive after T -> exit(timeout) end;
recv_after_32bit(_, _) ->
receive after 16#ffffFFFF -> exit(timeout) end.
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