diff options
Diffstat (limited to 'lib/kernel/src/application_master.erl')
| -rw-r--r-- | lib/kernel/src/application_master.erl | 71 |
1 files changed, 41 insertions, 30 deletions
diff --git a/lib/kernel/src/application_master.erl b/lib/kernel/src/application_master.erl index 3e636197bb..5da2b0b06c 100644 --- a/lib/kernel/src/application_master.erl +++ b/lib/kernel/src/application_master.erl @@ -1,18 +1,19 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1996-2013. All Rights Reserved. +%% Copyright Ericsson AB 1996-2016. 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. +%% 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% %% @@ -27,7 +28,7 @@ -include("application_master.hrl"). --record(state, {child, appl_data, children = [], procs = 0, gleader}). +-record(state, {child, appl_data, children = [], procs = 0, gleader, req=[]}). %%----------------------------------------------------------------- %% Func: start_link/1 @@ -103,9 +104,9 @@ call(AppMaster, Req) -> %%% The reason for not using the logical structrure is that %%% the application start function is synchronous, and %%% that the AM is GL. This means that if AM executed the start -%%% function, and this function uses spawn_request/1 -%%% or io, deadlock would occur. Therefore, this function is -%%% executed by the process X. Also, AM needs three loops; +%%% function, and this function uses io, deadlock would occur. +%%% Therefore, this function is executed by the process X. +%%% Also, AM needs three loops; %%% init_loop (waiting for the start function to return) %%% main_loop %%% terminate_loop (waiting for the process to die) @@ -125,7 +126,7 @@ init(Parent, Starter, ApplData, Type) -> State = #state{appl_data = ApplData, gleader = OldGleader}, case start_it(State, Type) of {ok, Pid} -> % apply(M,F,A) returned ok - set_timer(ApplData#appl_data.maxT), + ok = set_timer(ApplData#appl_data.maxT), unlink(Starter), proc_lib:init_ack(Starter, {ok,self()}), main_loop(Parent, State#state{child = Pid}); @@ -205,22 +206,25 @@ terminate_loop(Child, State) -> %%----------------------------------------------------------------- %% The Application Master is linked to *all* processes in the group -%% (application). +%% (application). %%----------------------------------------------------------------- handle_msg({get_child, Tag, From}, State) -> - From ! {Tag, get_child_i(State#state.child)}, - State; + get_child_i(State, Tag, From); handle_msg({stop, Tag, From}, State) -> catch terminate(normal, State), From ! {Tag, ok}, exit(normal); +handle_msg({child, Ref, GrandChild, Mod}, #state{req=Reqs0}=State) -> + {value, {_, Tag, From}, Reqs} = lists:keytake(Ref, 1, Reqs0), + From ! {Tag, {GrandChild, Mod}}, + State#state{req=Reqs}; handle_msg(_, State) -> State. - -terminate(Reason, State) -> - terminate_child(State#state.child, State), - kill_children(State#state.children), +terminate(Reason, State = #state{child=Child, children=Children, req=Reqs}) -> + _ = [From ! {Tag, error} || {_, Tag, From} <- Reqs], + terminate_child(Child, State), + kill_children(Children), exit(Reason). @@ -342,8 +346,8 @@ start_supervisor(Type, M, A) -> loop_it(Parent, Child, Mod, AppState) -> receive - {Parent, get_child} -> - Parent ! {self(), Child, Mod}, + {Parent, get_child, Ref} -> + Parent ! {child, Ref, Child, Mod}, loop_it(Parent, Child, Mod, AppState); {Parent, terminate} -> NewAppState = prep_stop(Mod, AppState), @@ -382,10 +386,15 @@ prep_stop(Mod, AppState) -> NewAppState end. -get_child_i(Child) -> - Child ! {self(), get_child}, - receive - {Child, GrandChild, Mod} -> {GrandChild, Mod} +get_child_i(#state{child=Child, req=Reqs}=State, Tag, From) -> + Ref = erlang:make_ref(), + case erlang:is_process_alive(Child) of + true -> + Child ! {self(), get_child, Ref}, + State#state{req=[{Ref, Tag, From}|Reqs]}; + false -> + From ! {Tag, error}, + State end. terminate_child_i(Child, State) -> @@ -418,4 +427,6 @@ kill_all_procs_1([], _, 0) -> ok; kill_all_procs_1([], _, _) -> kill_all_procs(). set_timer(infinity) -> ok; -set_timer(Time) -> timer:exit_after(Time, timeout). +set_timer(Time) -> + {ok, _} = timer:exit_after(Time, timeout), + ok. |