%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2010. 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(receive_SUITE).
%% Tests receive after.
-include_lib("test_server/include/test_server.hrl").
-export([all/0,groups/0,init_per_group/2,end_per_group/2,
call_with_huge_message_queue/1,receive_in_between/1]).
-export([init_per_testcase/2,fin_per_testcase/2]).
all() ->
[call_with_huge_message_queue, receive_in_between].
groups() ->
[].
init_per_group(_GroupName, Config) ->
Config.
end_per_group(_GroupName, Config) ->
Config.
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).
call_with_huge_message_queue(Config) when is_list(Config) ->
?line Pid = spawn_link(fun echo_loop/0),
?line {Time,ok} = tc(fun() -> calls(10, Pid) end),
?line [self() ! {msg,N} || N <- lists:seq(1, 500000)],
erlang:garbage_collect(),
?line {NewTime,ok} = tc(fun() -> calls(10, Pid) end),
io:format("Time for empty message queue: ~p", [Time]),
io:format("Time for huge message queue: ~p", [NewTime]),
case (NewTime+1) / (Time+1) of
Q when Q < 10 ->
ok;
Q ->
io:format("Q = ~p", [Q]),
?line ?t:fail()
end,
ok.
calls(0, _) -> ok;
calls(N, Pid) ->
{ok,{ultimate_answer,42}} = call(Pid, {ultimate_answer,42}),
calls(N-1, Pid).
call(Pid, Msg) ->
Mref = erlang:monitor(process, Pid),
Pid ! {Mref,{self(),Msg}},
receive
{Mref, Reply} ->
erlang:demonitor(Mref, [flush]),
{ok, Reply};
{'DOWN', Mref, _, _, Reason} ->
exit(Reason)
end.
receive_in_between(Config) when is_list(Config) ->
?line Pid = spawn_link(fun echo_loop/0),
?line [{ok,{a,b}} = call2(Pid, {a,b}) || _ <- lists:seq(1, 100000)],
ok.
call2(Pid, Msg) ->
self() ! dummy,
Mref = erlang:monitor(process, Pid),
Pid ! {Mref,{self(),Msg}},
receive_one(),
receive
{Mref,Reply} ->
erlang:demonitor(Mref, [flush]),
{ok,Reply};
{'DOWN',Mref,_,_,Reason} ->
exit(Reason)
end.
receive_one() ->
receive
dummy -> ok
end.
%%%
%%% Common helpers.
%%%
echo_loop() ->
receive
{Ref,{Pid,Msg}} ->
Pid ! {Ref,Msg},
echo_loop()
end.
tc(Fun) ->
timer:tc(erlang, apply, [Fun,[]]).
