%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2016. 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%
%%
-module(erts_dirty_process_code_checker).
-export([start/0]).
%%
%% The erts_dirty_process_code_checker is started at
%% VM boot by the VM. It is a spawned as a system
%% process, i.e, the whole VM will terminate if
%% this process terminates.
%%
start() ->
process_flag(trap_exit, true),
msg_loop().
msg_loop() ->
_ = receive
Request ->
handle_request(Request)
end,
msg_loop().
check_process(Requester, Target, ReqId, Module) ->
Result = erts_internal:check_dirty_process_code(Target, Module),
Requester ! {check_process_code, ReqId, Result}.
handle_request({Requester,
Target,
Prio,
{check_process_code,
ReqId,
Module} = Op}) ->
%%
%% Target may have stopped executing dirty since the
%% initial request was made. Check its current state
%% and try to send the request if possible; otherwise,
%% check the dirty executing process and send the result...
%%
try
case erts_internal:is_process_executing_dirty(Target) of
true ->
check_process(Requester, Target, ReqId, Module);
false ->
case erts_internal:request_system_task(Requester,
Target,
Prio,
Op) of
ok ->
ok;
dirty_execution ->
check_process(Requester, Target, ReqId, Module)
end
end
catch
_ : _ ->
ok %% Ignore all failures; someone passed us garbage...
end;
handle_request(_Garbage) ->
ignore.
