%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2016-2021. 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%
%%-----------------------------------------------------------------------------
%% @doc This module is an adaptation of Erlang's `gen_statem' module.
%%
%% It replaces all instances of `erlang:send/2' and `erlang:monitor/2' with
%% their Partisan counterparts.
%%
%% It maintains the `gen_statem' API with the following exceptions:
%%
%% <ul>
%% <li>`call/3` - overrides the 3rd to accept not only a timeout value but also
%% a list of options containing any of the following: `{timeout, timeout()}' |
%% `{channel, partisan:channel()}'.</li>
%% <li>`cast/3` - identical to `cast/2' with the 3th argument is a list of
%% options containing any of the following: `{channel,
%% partisan:channel()}'.</li>
%% <li>`send_request/4` - identical to `send_request/3' with the 4th argument
%% is a list of options containing any of the following: `{channel,
%% partisan:channel()}'.</li>
%% </ul>
%%
%% <blockquote class="warning">
%% <h4 class="warning">NOTICE</h4>
%% <p>At the moment this only works for
%% <code class="inline">partisan_pluggable_peer_service_manager</code> backend.
%% </p>
%% </blockquote>
%% @end
%% -----------------------------------------------------------------------------
-module(partisan_gen_statem).
-include_lib("partisan/include/partisan.hrl").
-include_lib("partisan/include/partisan_logger.hrl").
%% PARTISAN EXTENSIONS
-export([cast/3]).
-export([send_request/3]).
%%%
%%% NOTE: If init_ack() return values are modified, see comment
%%% above monitor_return() in gen.erl!
%%%
%% API
-export(
[start/3,start/4,start_link/3,start_link/4,
start_monitor/3,start_monitor/4,
stop/1,stop/3,
cast/2,call/2,call/3,
send_request/2,wait_response/1,wait_response/2,
receive_response/1,receive_response/2,check_response/2,
enter_loop/4,enter_loop/5,enter_loop/6,
reply/1,reply/2]).
%% gen callbacks
-export(
[init_it/6]).
%% sys callbacks
-export(
[system_continue/3,
system_terminate/4,
system_code_change/4,
system_get_state/1,
system_replace_state/2,
format_status/2]).
%% Internal callbacks
-export(
[wakeup_from_hibernate/3]).
%% logger callback
-export([format_log/1, format_log/2]).
%% Type exports for templates and callback modules
-export_type(
[event_type/0,
from/0,
callback_mode_result/0,
init_result/1,
init_result/2,
state_enter_result/1,
state_enter_result/2,
event_handler_result/1,
event_handler_result/2,
reply_action/0,
enter_action/0,
action/0
]).
%% Old types, not advertised
-export_type(
[state_function_result/0,
handle_event_result/0]).
%% Type that is exported just to be documented
-export_type([transition_option/0]).
%% Type exports for start_link & friends
-export_type(
[server_name/0,
server_ref/0,
start_opt/0,
start_ret/0,
enter_loop_opt/0]).
%%%==========================================================================
%%% Interface functions.
%%%==========================================================================
-type from() ::
{To :: pid() | partisan:remote_pid(), Tag :: term()}. % Reply-to specifier for call
-type state() ::
state_name() | % For StateName/3 callback functions
term(). % For handle_event/4 callback function
-type state_name() :: atom().
-type data() :: term().
-type event_type() ::
external_event_type() | timeout_event_type() | 'internal'.
-type external_event_type() ::
{'call',From :: from()} | 'cast' | 'info'.
-type timeout_event_type() ::
'timeout' | {'timeout', Name :: term()} | 'state_timeout'.
-type callback_mode_result() ::
callback_mode() | [callback_mode() | state_enter()].
-type callback_mode() :: 'state_functions' | 'handle_event_function'.
-type state_enter() :: 'state_enter'.
-type transition_option() ::
postpone() | hibernate() |
event_timeout() | generic_timeout() | state_timeout().
-type postpone() ::
%% If 'true' postpone the current event
%% and retry it when the state changes (=/=)
boolean().
-type hibernate() ::
%% If 'true' hibernate the server instead of going into receive
boolean().
-type event_timeout() ::
%% Generate a ('timeout', EventContent, ...) event
%% unless some other event is delivered
Time :: timeout() | integer().
-type generic_timeout() ::
%% Generate a ({'timeout',Name}, EventContent, ...) event
Time :: timeout() | integer().
-type state_timeout() ::
%% Generate a ('state_timeout', EventContent, ...) event
%% unless the state is changed
Time :: timeout() | integer().
-type timeout_option() :: {abs,Abs :: boolean()}.
-type action() ::
%% During a state change:
%% * NextState and NewData are set.
%% * All action()s are executed in order of appearance.
%% * Postponing the current event is performed
%% iff 'postpone' is 'true'.
%% * A state timeout is started iff 'timeout' is set.
%% * Pending events are handled or if there are
%% no pending events the server goes into receive
%% or hibernate (iff 'hibernate' is 'true')
%%
%% These action()s are executed in order of appearance
%% in the containing list. The ones that set options
%% will override any previous so the last of each kind wins.
%%
'postpone' | % Set the postpone option
{'postpone', Postpone :: postpone()} |
%%
%% All 'next_event' events are kept in a list and then
%% inserted at state changes so the first in the
%% action() list is the first to be delivered.
{'next_event', % Insert event as the next to handle
EventType :: event_type(),
EventContent :: term()} |
{'change_callback_module', NewModule :: module()} |
{'push_callback_module', NewModule :: module()} |
'pop_callback_module' |
enter_action().
-type enter_action() ::
'hibernate' | % Set the hibernate option
{'hibernate', Hibernate :: hibernate()} |
timeout_action() |
reply_action().
-type timeout_action() ::
(Time :: event_timeout()) | % {timeout,Time,Time}
{'timeout', % Set the event_timeout option
Time :: event_timeout(), EventContent :: term()} |
{'timeout', % Set the event_timeout option
Time :: event_timeout(),
EventContent :: term(),
Options :: (timeout_option() | [timeout_option()])} |
%%
{{'timeout', Name :: term()}, % Set the generic_timeout option
Time :: generic_timeout(), EventContent :: term()} |
{{'timeout', Name :: term()}, % Set the generic_timeout option
Time :: generic_timeout(),
EventContent :: term(),
Options :: (timeout_option() | [timeout_option()])} |
%%
{'state_timeout', % Set the state_timeout option
Time :: state_timeout(), EventContent :: term()} |
{'state_timeout', % Set the state_timeout option
Time :: state_timeout(),
EventContent :: term(),
Options :: (timeout_option() | [timeout_option()])} |
timeout_cancel_action() |
timeout_update_action().
-type timeout_cancel_action() ::
{'timeout', 'cancel'} |
{{'timeout', Name :: term()}, 'cancel'} |
{'state_timeout', 'cancel'}.
-type timeout_update_action() ::
{'timeout', 'update', EventContent :: term()} |
{{'timeout', Name :: term()}, 'update', EventContent :: term()} |
{'state_timeout', 'update', EventContent :: term()}.
-type reply_action() ::
{'reply', % Reply to a caller
From :: from(), Reply :: term()}.
-type init_result(StateType) :: init_result(StateType, term()).
-type init_result(StateType, DataType) ::
{ok, State :: StateType, Data :: DataType} |
{ok, State :: StateType, Data :: DataType,
Actions :: [action()] | action()} |
'ignore' |
{'stop', Reason :: term()}.
%% Old, not advertised
-type state_function_result() ::
event_handler_result(state_name()).
-type handle_event_result() ::
event_handler_result(state()).
%%
-type state_enter_result(State) :: state_enter_result(State, term()).
-type state_enter_result(State, DataType) ::
{'next_state', % {next_state,State,NewData,[]}
State,
NewData :: DataType} |
{'next_state', % State entry for state State
State,
NewData :: DataType,
Actions :: [enter_action()] | enter_action()} |
state_callback_result(enter_action()).
-type event_handler_result(StateType) ::
event_handler_result(StateType, term()).
-type event_handler_result(StateType, DataType) ::
{'next_state', % {next_state,NextState,NewData,[]}
NextState :: StateType,
NewData :: DataType} |
{'next_state', % State transition, maybe to the same state
NextState :: StateType,
NewData :: DataType,
Actions :: [action()] | action()} |
state_callback_result(action()).
-type state_callback_result(ActionType) ::
state_callback_result(ActionType, term()).
-type state_callback_result(ActionType, DataType) ::
{'keep_state', % {keep_state,NewData,[]}
NewData :: DataType} |
{'keep_state', % Keep state, change data
NewData :: DataType,
Actions :: [ActionType] | ActionType} |
'keep_state_and_data' | % {keep_state_and_data,[]}
{'keep_state_and_data', % Keep state and data -> only actions
Actions :: [ActionType] | ActionType} |
%%
{'repeat_state', % {repeat_state,NewData,[]}
NewData :: DataType} |
{'repeat_state', % Repeat state, change data
NewData :: DataType,
Actions :: [ActionType] | ActionType} |
'repeat_state_and_data' | % {repeat_state_and_data,[]}
{'repeat_state_and_data', % Repeat state and data -> only actions
Actions :: [ActionType] | ActionType} |
%%
'stop' | % {stop,normal}
{'stop', % Stop the server
Reason :: term()} |
{'stop', % Stop the server
Reason :: term(),
NewData :: DataType} |
%%
{'stop_and_reply', % Reply then stop the server
Reason :: term(),
Replies :: [reply_action()] | reply_action()} |
{'stop_and_reply', % Reply then stop the server
Reason :: term(),
Replies :: [reply_action()] | reply_action(),
NewData :: DataType}.
-type request_id() :: term().
%% The state machine init function. It is called only once and
%% the server is not running until this function has returned
%% an {ok, ...} tuple. Thereafter the state callbacks are called
%% for all events to this server.
-callback init(Args :: term()) -> init_result(state()).
%% This callback shall return the callback mode of the callback module.
%%
%% It is called once after init/0 and code_change/4 but before
%% the first state callback StateName/3 or handle_event/4.
-callback callback_mode() -> callback_mode_result().
%% Example state callback for StateName = 'state_name'
%% when callback_mode() =:= state_functions.
%%
%% In this mode all states has to be of type state_name() i.e atom().
%%
%% Note that the only callbacks that have arity 3 are these
%% StateName/3 callbacks and terminate/3, so the state name
%% 'terminate' is unusable in this mode.
-callback state_name(
'enter',
OldStateName :: state_name(),
Data :: data()) ->
state_enter_result('state_name');
(event_type(),
EventContent :: term(),
Data :: data()) ->
event_handler_result(state_name()).
%%
%% State callback for all states
%% when callback_mode() =:= handle_event_function.
-callback handle_event(
'enter',
OldState :: state(),
State, % Current state
Data :: data()) ->
state_enter_result(State);
(event_type(),
EventContent :: term(),
State :: state(), % Current state
Data :: data()) ->
event_handler_result(state()).
%% Clean up before the server terminates.
-callback terminate(
Reason :: 'normal' | 'shutdown' | {'shutdown', term()}
| term(),
State :: state(),
Data :: data()) ->
any().
%% Note that the new code can expect to get an OldState from
%% the old code version not only in code_change/4 but in the first
%% state callback function called thereafter
-callback code_change(
OldVsn :: term() | {'down', term()},
OldState :: state(),
OldData :: data(),
Extra :: term()) ->
{ok, NewState :: state(), NewData :: data()} |
(Reason :: term()).
%% Format the callback module state in some sensible that is
%% often condensed way. For StatusOption =:= 'normal' the preferred
%% return term is [{data,[{"State",FormattedState}]}], and for
%% StatusOption =:= 'terminate' it is just FormattedState.
-callback format_status(
StatusOption,
[ [{Key :: term(), Value :: term()}] |
state() |
data()]) ->
Status :: term() when
StatusOption :: 'normal' | 'terminate'.
-optional_callbacks(
[format_status/2, % Has got a default implementation
terminate/3, % Has got a default implementation
code_change/4, % Only needed by advanced soft upgrade
%%
state_name/3, % Just an example callback;
%% for callback_mode() =:= state_functions
%% there has to be a StateName/3 callback function
%% for every StateName in your state machine,
%% but not one has to be named 'state_name'
%%
handle_event/4 % Only for callback_mode() =:= handle_event_function
]).
%% Type validation functions
%% - return true if the value is of the type, false otherwise
-compile(
{inline,
[callback_mode/1, state_enter/1,
event_type/1, from/1, timeout_event_type/1]}).
%%
callback_mode(CallbackMode) ->
case CallbackMode of
state_functions -> true;
handle_event_function -> true;
_ -> false
end.
%%
state_enter(StateEnter) ->
case StateEnter of
state_enter ->
true;
_ ->
false
end.
%%
event_type(Type) ->
case Type of
{call,From} -> from(From);
%%
cast -> true;
info -> true;
internal -> true;
_ -> timeout_event_type(Type)
end.
%%
from({Pid, _}) when is_pid(Pid) -> true;
from({Term, _}) -> partisan_remote_ref:is_pid(Term);
from(_) -> false.
%%
timeout_event_type(Type) ->
case Type of
timeout -> true;
state_timeout -> true;
{timeout,_Name} -> true;
_ -> false
end.
-define(
relative_timeout(T),
((is_integer(T) andalso 0 =< (T)) orelse (T) =:= infinity)).
-define(
absolute_timeout(T),
(is_integer(T) orelse (T) =:= infinity)).
-define(
STACKTRACE(),
element(2, erlang:process_info(self(), current_stacktrace))).
-define(not_sys_debug, []).
%%
%% This is a macro to only evaluate arguments if Debug =/= [].
%% Debug is evaluated 2 times.
-define(
sys_debug(Debug, Extra, SystemEvent),
case begin Debug end of
?not_sys_debug ->
begin Debug end;
_ ->
sys_debug(
begin Debug end, begin Extra end, begin SystemEvent end)
end).
-record(params,
{callback_mode = undefined :: callback_mode() | undefined,
state_enter = false :: boolean(),
parent :: pid(),
modules :: [module()],
name :: atom() | pid(),
hibernate_after = infinity :: timeout()
}).
-record(state,
{state_data = {undefined,undefined} ::
{State :: term(),Data :: term()},
postponed = [] :: [{event_type(),term()}],
timers = #{t0q => []} ::
#{
%% Timeout 0 Queue.
%% Marked in the table with TimerRef = 0.
%% Stored here because they also are updated
%% by e.g cancel_timer/3.
't0q' := [timeout_event_type()],
TimeoutType :: timeout_event_type() =>
{TimerRef :: reference() | 0,
TimeoutMsg :: term()}},
hibernate = false :: boolean()
}).
%%%==========================================================================
%%% API
-type server_name() ::
{'global', GlobalName :: term()}
| {'via', RegMod :: module(), Name :: term()}
| {'local', atom()}.
-type server_ref() ::
pid()
| (LocalName :: atom())
| {Name :: atom(), Node :: atom()}
| {'global', GlobalName :: term()}
| {'via', RegMod :: module(), ViaName :: term()}
| partisan:remote_pid()
| partisan:remote_name().
-type start_opt() ::
{'timeout', Time :: timeout()}
| {'channel', partisan:channel()}
| {'spawn_opt', [partisan_proc_lib:start_spawn_option()]}
| enter_loop_opt().
-type start_ret() ::
{'ok', pid()}
| 'ignore'
| {'error', term()}.
-type start_mon_ret() ::
{'ok', {pid(),reference()}}
| 'ignore'
| {'error', term()}.
-type enter_loop_opt() ::
{'hibernate_after', HibernateAfterTimeout :: timeout()}
| {'debug', Dbgs :: [partisan_sys:debug_option()]}.
%% Start a state machine
-spec start(
Module :: module(), Args :: term(), Opts :: [start_opt()]) ->
start_ret().
start(Module, Args, Opts) ->
partisan_gen:start(?MODULE, nolink, Module, Args, Opts).
%%
-spec start(
ServerName :: server_name(),
Module :: module(), Args :: term(), Opts :: [start_opt()]) ->
start_ret().
start(ServerName, Module, Args, Opts) ->
partisan_gen:start(?MODULE, nolink, ServerName, Module, Args, Opts).
%% Start and link to a state machine
-spec start_link(
Module :: module(), Args :: term(), Opts :: [start_opt()]) ->
start_ret().
start_link(Module, Args, Opts) ->
partisan_gen:start(?MODULE, link, Module, Args, Opts).
%%
-spec start_link(
ServerName :: server_name(),
Module :: module(), Args :: term(), Opts :: [start_opt()]) ->
start_ret().
start_link(ServerName, Module, Args, Opts) ->
partisan_gen:start(?MODULE, link, ServerName, Module, Args, Opts).
%% Start and monitor a state machine
-spec start_monitor(
Module :: module(), Args :: term(), Opts :: [start_opt()]) ->
start_mon_ret().
start_monitor(Module, Args, Opts) ->
partisan_gen:start(?MODULE, monitor, Module, Args, Opts).
%%
-spec start_monitor(
ServerName :: server_name(),
Module :: module(), Args :: term(), Opts :: [start_opt()]) ->
start_mon_ret().
start_monitor(ServerName, Module, Args, Opts) ->
partisan_gen:start(?MODULE, monitor, ServerName, Module, Args, Opts).
%% Stop a state machine
-spec stop(ServerRef :: server_ref()) -> ok.
stop(ServerRef) ->
partisan_gen:stop(ServerRef).
%%
-spec stop(
ServerRef :: server_ref(),
Reason :: term(),
Timeout :: timeout()) -> ok.
stop(ServerRef, Reason, Timeout) ->
partisan_gen:stop(ServerRef, Reason, Timeout).
%% Send an event to a state machine that arrives with type 'event'
-spec cast(ServerRef :: server_ref(), Msg :: term()) -> ok.
cast(ServerRef, Msg) when is_pid(ServerRef) ->
send(ServerRef, wrap_cast(Msg));
cast(ServerRef, Msg) when is_atom(ServerRef) ->
send(ServerRef, wrap_cast(Msg));
cast({global,Name}, Msg) ->
try global:send(Name, wrap_cast(Msg)) of
_ -> ok
catch
_:_ -> ok
end;
cast({via,RegMod,Name}, Msg) ->
try RegMod:send(Name, wrap_cast(Msg)) of
_ -> ok
catch
_:_ -> ok
end;
cast({Name, Node} = ServerRef, Msg) when is_atom(Name), is_atom(Node) ->
case Node == partisan:node() of
true ->
%% Optimisation
send(Name, Msg);
false ->
cast(ServerRef, Msg, [])
end;
cast(Dest, Msg) ->
%% Maybe partisan_remote_ref
cast(Dest, Msg, []).
%% Partisan addition
cast(Dest, Msg, _) when is_pid(Dest); is_atom(Dest) ->
cast(Dest, Msg);
cast({global,_} = GRef, Msg, _) ->
cast(GRef, Msg);
cast({via, _, _} = ViaRef, Msg, _) ->
cast(ViaRef, Msg);
cast(Dest, Msg, Opts) ->
%% Set opts will set the default channel is non is defined, so there is no
%% need to cleanup the calling process dict.
%% We do this to avoid changing this code too much, but we might need to do
%% it in the end.
partisan_send(Dest, wrap_cast(Msg), Opts).
%% Call a state machine (synchronous; a reply is expected) that
%% arrives with type {call,From}
-spec call(ServerRef :: server_ref(), Request :: term()) -> Reply :: term().
call(ServerRef, Request) ->
call(ServerRef, Request, infinity).
%%
-spec call(
ServerRef :: server_ref(),
Request :: term(),
Timeout ::
timeout() |
{'clean_timeout',T :: timeout()} |
{'dirty_timeout',T :: timeout()} |
%% Partisan addition
[
{timeout, timeout()} |
{'clean_timeout',T :: timeout()} |
{'dirty_timeout',T :: timeout()} |
{any(), term()}
]
) ->Reply :: term().
call(ServerRef, Request, infinity = T = Timeout) ->
call_dirty(ServerRef, Request, Timeout, T);
call(ServerRef, Request, {dirty_timeout, T} = Timeout) ->
call_dirty(ServerRef, Request, Timeout, T);
call(ServerRef, Request, {clean_timeout, T} = Timeout) ->
call_clean(ServerRef, Request, Timeout, T);
call(ServerRef, Request, {_, _} = Timeout) ->
erlang:error(badarg, [ServerRef,Request,Timeout]);
%% Partisan addition
call(ServerRef, Request, Opts) when is_list(Opts) ->
%% We are ignoting all opts, we should merge them with
%% partisan:get_opts and pass them to call_clean
%% or temp set them in process dict as call_opts
Timeout = get_timeout(Opts),
call(ServerRef, Request, Timeout);
call(ServerRef, Request, Timeout) ->
call_clean(ServerRef, Request, Timeout, Timeout).
get_timeout([{timeout, infinity = Val}|_]) ->
Val;
get_timeout([{dirty_timeout, _} = Val|_]) ->
Val;
get_timeout([{clean_timeout, _} = Val|_]) ->
Val;
get_timeout([{_, _}|T]) ->
get_timeout(T);
get_timeout([]) ->
infinity.
-spec send_request(ServerRef::server_ref(), Request::term()) ->
RequestId::request_id().
send_request(Name, Request) ->
partisan_gen:send_request(Name, '$gen_call', Request).
%% Partisan addition
-spec send_request(Name::server_ref(), Request::term(), Opts :: list()) -> RequestId::request_id().
send_request(Name, Request, Opts) ->
partisan_gen:send_request(Name, '$gen_call', Request, Opts).
-spec wait_response(RequestId::request_id()) ->
{reply, Reply::term()} | {error, {term(), server_ref()}}.
wait_response(RequestId) ->
partisan_gen:wait_response(RequestId, infinity).
-spec wait_response(RequestId::request_id(), timeout()) ->
{reply, Reply::term()} | 'timeout' | {error, {term(), server_ref()}}.
wait_response(RequestId, Timeout) ->
partisan_gen:wait_response(RequestId, Timeout).
-spec receive_response(RequestId::request_id()) ->
{reply, Reply::term()} | {error, {term(), server_ref()}}.
receive_response(RequestId) ->
partisan_gen:receive_response(RequestId, infinity).
-spec receive_response(RequestId::request_id(), timeout()) ->
{reply, Reply::term()} | 'timeout' | {error, {term(), server_ref()}}.
receive_response(RequestId, Timeout) ->
partisan_gen:receive_response(RequestId, Timeout).
-spec check_response(Msg::term(), RequestId::request_id()) ->
{reply, Reply::term()} | 'no_reply' | {error, {term(), server_ref()}}.
check_response(Msg, RequestId) ->
partisan_gen:check_response(Msg, RequestId).
%% Reply from a state machine callback to whom awaits in call/2
-spec reply([reply_action()] | reply_action()) -> ok.
reply({reply,From,Reply}) ->
reply(From, Reply);
reply(Replies) when is_list(Replies) ->
replies(Replies).
%%
-compile({inline, [reply/2]}).
-spec reply(From :: from(), Reply :: term()) -> ok.
reply(From, Reply) ->
partisan_gen:reply(From, Reply).
%% Instead of starting the state machine through start/3,4
%% or start_link/3,4 turn the current process presumably
%% started by proc_lib into a state machine using
%% the same arguments as you would have returned from init/1
-spec enter_loop(
Module :: module(), Opts :: [enter_loop_opt()],
State :: state(), Data :: data()) ->
no_return().
enter_loop(Module, Opts, State, Data) ->
enter_loop(Module, Opts, State, Data, self()).
%%
-spec enter_loop(
Module :: module(), Opts :: [enter_loop_opt()],
State :: state(), Data :: data(),
Server_or_Actions ::
server_name() | pid() | [action()]) ->
no_return().
enter_loop(Module, Opts, State, Data, Server_or_Actions) ->
if
is_list(Server_or_Actions) ->
enter_loop(Module, Opts, State, Data, self(), Server_or_Actions);
true ->
enter_loop(Module, Opts, State, Data, Server_or_Actions, [])
end.
%%
-spec enter_loop(
Module :: module(), Opts :: [enter_loop_opt()],
State :: state(), Data :: data(),
Server :: server_name() | pid(),
Actions :: [action()] | action()) ->
no_return().
enter_loop(Module, Opts, State, Data, Server, Actions) ->
is_atom(Module) orelse error({atom,Module}),
Parent = partisan_gen:get_parent(),
Name = partisan_gen:get_proc_name(Server),
Debug = partisan_gen:debug_options(Name, Opts),
HibernateAfterTimeout = partisan_gen:hibernate_after(Opts),
enter(
Parent, Debug, Module, Name, HibernateAfterTimeout,
State, Data, Actions).
%%---------------------------------------------------------------------------
%% API helpers
-compile({inline, [wrap_cast/1]}).
wrap_cast(Event) ->
{'$gen_cast',Event}.
call_dirty(ServerRef, Request, Timeout, T) ->
try partisan_gen:call(ServerRef, '$gen_call', Request, T) of
{ok,Reply} ->
Reply
catch
Class:Reason:Stacktrace ->
erlang:raise(
Class,
{Reason,{?MODULE,call,[ServerRef,Request,Timeout]}},
Stacktrace)
end.
-dialyzer([{nowarn_function, call_clean/4}]).
call_clean({Name, Node} = ServerRef, Request, Timeout, T)
when is_atom(Name), is_atom(Node) ->
case Node == partisan:node() of
true ->
call_dirty(ServerRef, Request, Timeout, T);
false ->
do_call_clean(ServerRef, Request, Timeout, T)
end;
call_clean(ServerRef, Request, Timeout, T) ->
case partisan:is_local_pid(ServerRef) of
true ->
%% No need to use a proxy locally since we know alias will be
%% used as of OTP 24 which will prevent garbage responses...
call_dirty(ServerRef, Request, Timeout, T);
false ->
do_call_clean(ServerRef, Request, Timeout, T)
end.
do_call_clean(ServerRef, Request, Timeout, T) ->
%% Call server through proxy process to dodge any late reply
%%
%% We still need a proxy in the distributed case since we may
%% communicate with a node that does not understand aliases.
%% This can be removed when alias support is mandatory.
%% Probably in OTP 26.
Ref = partisan:make_ref(),
Self = self(),
Pid = spawn(
fun () ->
Self !
try partisan_gen:call(
ServerRef, '$gen_call', Request, T) of
Result ->
{Ref,Result}
catch Class:Reason:Stacktrace ->
{Ref,Class,Reason,Stacktrace}
end
end),
Mref = erlang:monitor(process, Pid),
receive
{Ref,Result} ->
erlang:demonitor(Mref, [flush]),
case Result of
{ok,Reply} ->
Reply
end;
{Ref,Class,Reason,Stacktrace} ->
erlang:demonitor(Mref, [flush]),
erlang:raise(
Class,
{Reason,{?MODULE,call,[ServerRef,Request,Timeout]}},
Stacktrace);
{'DOWN',Ref,_,_,Reason} ->
%% There is a theoretical possibility that the
%% proxy process gets killed between try--of and !
%% so this clause is in case of that
exit(Reason)
end.
replies([{reply,From,Reply}|Replies]) ->
reply(From, Reply),
replies(Replies);
replies([]) ->
ok.
%% Might actually not send the message in case of caught exception
send(Proc, Msg) ->
try erlang:send(Proc, Msg)
catch
error:_ -> ok
end,
ok.
partisan_send(Dest, Msg) ->
partisan_send(Dest, Msg, partisan_gen:get_opts()).
partisan_send({Name, Node}, Msg, Opts) ->
partisan:forward_message(Node, Name, Msg, partisan_gen:get_opts(Opts));
partisan_send(Dest, Msg, Opts) ->
%% Simulate the error we would have gotten in cast/2
partisan_remote_ref:is_type(Dest) orelse error(function_clause),
partisan:forward_message(Dest, Msg, partisan_gen:get_opts(Opts)).
%% Here the init_it/6 and enter_loop/5,6,7 functions converge
enter(
Parent, Debug, Module, Name, HibernateAfterTimeout,
State, Data, Actions) ->
%% The values should already have been type checked
Q = [{internal,init_state}],
%% We enforce {postpone,false} to ensure that
%% our fake Event gets discarded, thought it might get logged
Actions_1 = listify(Actions) ++ [{postpone,false}],
P =
#params{
parent = Parent,
modules = [Module],
name = Name,
hibernate_after = HibernateAfterTimeout},
S = #state{state_data = {State,Data}},
Debug_1 = ?sys_debug(Debug, Name, {enter,State}),
loop_state_callback(
P, Debug_1, S, Q, {State,Data},
%% Tunneling Actions through CallbackEvent here...
%% Special path to go to action handling, after first
%% finding out the callback mode. CallbackEvent is
%% a 2-tuple and Actions a list, which achieves this distinction.
Actions_1).
%%%==========================================================================
%%% gen callbacks
init_it(Starter, self, ServerRef, Module, Args, Opts) ->
init_it(Starter, self(), ServerRef, Module, Args, Opts);
init_it(Starter, Parent, ServerRef, Module, Args, Opts) ->
Name = partisan_gen:get_proc_name(ServerRef),
Debug = partisan_gen:debug_options(Name, Opts),
HibernateAfterTimeout = partisan_gen:hibernate_after(Opts),
try Module:init(Args) of
Result ->
init_result(
Starter, Parent, ServerRef, Module, Result,
Name, Debug, HibernateAfterTimeout)
catch
Result ->
init_result(
Starter, Parent, ServerRef, Module, Result,
Name, Debug, HibernateAfterTimeout);
Class:Reason:Stacktrace ->
partisan_gen:unregister_name(ServerRef),
partisan_proc_lib:init_ack(Starter, {error,Reason}),
error_info(
Class, Reason, Stacktrace, Debug,
#params{parent = Parent, name = Name, modules = [Module]},
#state{}, []),
erlang:raise(Class, Reason, Stacktrace)
end.
%%---------------------------------------------------------------------------
%% gen callbacks helpers
init_result(
Starter, Parent, ServerRef, Module, Result,
Name, Debug, HibernateAfterTimeout) ->
case Result of
{ok,State,Data} ->
partisan_proc_lib:init_ack(Starter, {ok,self()}),
enter(
Parent, Debug, Module, Name, HibernateAfterTimeout,
State, Data, []);
{ok,State,Data,Actions} ->
partisan_proc_lib:init_ack(Starter, {ok,self()}),
enter(
Parent, Debug, Module, Name, HibernateAfterTimeout,
State, Data, Actions);
{stop,Reason} ->
partisan_gen:unregister_name(ServerRef),
partisan_proc_lib:init_ack(Starter, {error,Reason}),
exit(Reason);
ignore ->
partisan_gen:unregister_name(ServerRef),
partisan_proc_lib:init_ack(Starter, ignore),
exit(normal);
_ ->
partisan_gen:unregister_name(ServerRef),
Error = {bad_return_from_init,Result},
partisan_proc_lib:init_ack(Starter, {error,Error}),
error_info(
error, Error, ?STACKTRACE(), Debug,
#params{parent = Parent, name = Name, modules = [Module]},
#state{}, []),
exit(Error)
end.
%%%==========================================================================
%%% sys callbacks
%%%
%%% We use {P,S} as state (Misc) for the sys module,
%%% wrap/unwrap it for the server loop* and update
%%% P#params{parent = Parent}.
system_continue(Parent, Debug, {P,S}) ->
loop(update_parent(P, Parent), Debug, S).
system_terminate(Reason, Parent, Debug, {P,S}) ->
terminate(
exit, Reason, ?STACKTRACE(),
update_parent(P, Parent), Debug, S, []).
system_code_change(
{#params{modules = [Module | _]} = P,
#state{state_data = {State,Data}} = S},
_Mod, OldVsn, Extra) ->
case
try Module:code_change(OldVsn, State, Data, Extra)
catch
Result -> Result
end
of
{ok,NewState,NewData} ->
{ok,
{P#params{callback_mode = undefined},
S#state{state_data = {NewState,NewData}}}};
{ok,_} = Error ->
error({case_clause,Error});
Error ->
Error
end.
system_get_state({_P,#state{state_data = State_Data}}) ->
{ok,State_Data}.
system_replace_state(
StateFun, {P,#state{state_data = State_Data} = S}) ->
%%
NewState_NewData = StateFun(State_Data),
{ok,NewState_NewData,{P,S#state{state_data = NewState_NewData}}}.
format_status(
Opt,
[PDict,SysState,Parent,Debug,
{#params{name = Name, modules = Modules} = P,
#state{postponed = Postponed, timers = Timers} = S}]) ->
Header = partisan_gen:format_status_header("Status for state machine", Name),
Log = partisan_sys:get_log(Debug),
[{header,Header},
{data,
[{"Status",SysState},
{"Parent",Parent},
{"Modules",Modules},
{"Time-outs",list_timeouts(Timers)},
{"Logged Events",Log},
{"Postponed",Postponed}]} |
case format_status(Opt, PDict, update_parent(P, Parent), S) of
L when is_list(L) -> L;
T -> [T]
end].
%% Update #params.parent only if it differs. This should not
%% be possible today (OTP-22.0), but could happen for example
%% if someone implements changing a server's parent
%% in a new sys call.
-compile({inline, update_parent/2}).
update_parent(P, Parent) ->
case P of
#params{parent = Parent} ->
P;
#params{} ->
P#params{parent = Parent}
end.
%%---------------------------------------------------------------------------
%% Format debug messages. Print them as the call-back module sees
%% them, not as the real erlang messages. Use trace for that.
%%---------------------------------------------------------------------------
sys_debug(Debug, NameState, Entry) ->
partisan_sys:handle_debug(Debug, fun print_event/3, NameState, Entry).
print_event(Dev, SystemEvent, Name) ->
case SystemEvent of
{in,Event,State} ->
io:format(
Dev, "*DBG* ~tp receive ~ts in state ~tp~n",
[Name,event_string(Event),State]);
{code_change,Event,State} ->
io:format(
Dev, "*DBG* ~tp receive ~ts after code change in state ~tp~n",
[Name,event_string(Event),State]);
{out,Reply,{To,_Tag}} ->
io:format(
Dev, "*DBG* ~tp send ~tp to ~tw~n",
[Name,Reply,To]);
{enter,State} ->
io:format(
Dev, "*DBG* ~tp enter in state ~tp~n",
[Name,State]);
{start_timer,Action,State} ->
io:format(
Dev, "*DBG* ~tp start_timer ~tp in state ~tp~n",
[Name,Action,State]);
{insert_timeout,Event,State} ->
io:format(
Dev, "*DBG* ~tp insert_timeout ~tp in state ~tp~n",
[Name,Event,State]);
{terminate,Reason,State} ->
io:format(
Dev, "*DBG* ~tp terminate ~tp in state ~tp~n",
[Name,Reason,State]);
{Tag,Event,State,NextState}
when Tag =:= postpone; Tag =:= consume ->
StateString =
case NextState of
State ->
io_lib:format("~tp", [State]);
_ ->
io_lib:format("~tp => ~tp", [State,NextState])
end,
io:format(
Dev, "*DBG* ~tp ~tw ~ts in state ~ts~n",
[Name,Tag,event_string(Event),StateString])
end.
event_string(Event) ->
case Event of
{{call,{Pid,_Tag}},Request} ->
io_lib:format("call ~tp from ~tw", [Request,Pid]);
{EventType,EventContent} ->
io_lib:format("~tw ~tp", [EventType,EventContent])
end.
%%%==========================================================================
%%% Internal callbacks
wakeup_from_hibernate(P, Debug, S) ->
%% It is a new message that woke us up so we have to receive it now
loop_receive(P, Debug, S).
%%%==========================================================================
%%% State Machine engine implementation on proc_lib/gen
%% Server loop, consists of all loop* functions
%% and detours through partisan_sys:handle_system_message/7 and partisan_proc_lib:hibernate/3
%%
%% The loop tries to keep all temporary values in arguments
%% and takes shortcuts for ?not_sys_debug, empty lists, etc.
%% The engine state #state{} is picked apart during the loop,
%% new values are kept in arguments, and a new #state{} is
%% composed at the end of the loop. #params{} collect engine
%% state fields that rarely changes.
%%
%% The loop is optimized a bit for staying in the loop, assuming that
%% system events are rare. So a detour to sys requires re-packing
%% of the engine state.
%% Entry point for system_continue/3
%%
loop(P, Debug, #state{hibernate = true} = S) ->
loop_hibernate(P, Debug, S);
loop(P, Debug, S) ->
loop_receive(P, Debug, S).
%% Go to hibernation
%%
loop_hibernate(P, Debug, S) ->
%%
%% Does not return but restarts process at
%% wakeup_from_hibernate/3 that jumps to loop_receive/3
%%
partisan_proc_lib:hibernate(?MODULE, wakeup_from_hibernate, [P, Debug, S]),
error(
{should_not_have_arrived_here_but_instead_in,
{?MODULE,wakeup_from_hibernate,3}}).
%% Entry point for wakeup_from_hibernate/3
%%
%% Receive a new process message
%%
loop_receive(
#params{hibernate_after = HibernateAfterTimeout} = P, Debug, S) ->
%%
receive
Msg ->
case Msg of
{'$gen_call',From,Request} ->
loop_receive_result(P, Debug, S, {{call,From},Request});
{'$gen_cast',Cast} ->
loop_receive_result(P, Debug, S, {cast,Cast});
%%
{timeout,TimerRef,TimeoutType} ->
case S#state.timers of
#{TimeoutType := {TimerRef,TimeoutMsg}} = Timers
when TimeoutType =/= t0q->
%% Our timer
Timers_1 = maps:remove(TimeoutType, Timers),
S_1 = S#state{timers = Timers_1},
loop_receive_result(
P, Debug, S_1, {TimeoutType,TimeoutMsg});
#{} ->
loop_receive_result(P, Debug, S, {info,Msg})
end;
%%
{system,Pid,Req} ->
%% Does not return but tail recursively calls
%% system_continue/3 that jumps to loop/3
partisan_sys:handle_system_msg(
Req, Pid, P#params.parent, ?MODULE, Debug,
{P,S},
S#state.hibernate);
{'EXIT',Pid,Reason} ->
case P#params.parent of
Pid ->
terminate(
exit, Reason, ?STACKTRACE(), P, Debug, S, []);
_ ->
loop_receive_result(P, Debug, S, {info,Msg})
end;
%%
_ ->
loop_receive_result(P, Debug, S, {info,Msg})
end
after
HibernateAfterTimeout ->
loop_hibernate(P, Debug, S)
end.
%% We have received an event
%%
loop_receive_result(P, ?not_sys_debug = Debug, S, Event) ->
%% Here is the queue of not yet handled events created
Events = [],
loop_event(P, Debug, S, Event, Events);
loop_receive_result(
#params{name = Name, callback_mode = CallbackMode} = P, Debug,
#state{state_data = {State,_Data}} = S, Event) ->
Debug_1 =
case CallbackMode of
undefined ->
sys_debug(Debug, Name, {code_change,Event,State});
_ ->
sys_debug(Debug, Name, {in,Event,State})
end,
%% Here is the queue of not yet handled events created
Events = [],
loop_event(P, Debug_1, S, Event, Events).
%% Handle one event; received or enqueued
%%
loop_event(
P, Debug, #state{hibernate = true} = S, Event, Events) ->
%%
%% If (this old) Hibernate is true here it can only be
%% because it was set from an event action
%% and we did not go into hibernation since there were
%% events in queue, so we do what the user
%% might rely on i.e collect garbage which
%% would have happened if we actually hibernated
%% and immediately was awakened.
%%
_ = garbage_collect(),
loop_event_handler(P, Debug, S, Event, Events);
loop_event(P, Debug, S, Event, Events) ->
loop_event_handler(P, Debug, S, Event, Events).
%% Call the state function, eventually
%%
-compile({inline, [loop_event_handler/5]}).
loop_event_handler(
P, Debug, #state{state_data = State_Data} = S, Event, Events) ->
%%
%% The field 'hibernate' in S is now invalid and will be
%% restored when looping back to loop/3 or loop_event/5.
%%
Q = [Event|Events],
loop_state_callback(P, Debug, S, Q, State_Data, Event).
%% Make a state enter call to the state function, we loop back here
%% from further down if state enter calls are enabled
%%
loop_state_enter(
P, Debug, #state{state_data = {PrevState,_PrevData}} = S,
Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone) ->
%%
StateCall = false,
CallbackEvent = {enter,PrevState},
loop_state_callback(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent).
%% Make a state call (not state enter call) to the state function
%%
loop_state_callback(P, Debug, S, Q, State_Data, CallbackEvent) ->
NextEventsR = [],
Hibernate = false,
TimeoutsR = [],
Postpone = false,
StateCall = true,
loop_state_callback(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent).
%%
loop_state_callback(
#params{callback_mode = undefined, modules = [Module | _]} = P,
Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent) ->
%%
%% Figure out the callback mode
%%
try Module:callback_mode() of
CallbackMode ->
loop_callback_mode_result(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent,
CallbackMode, listify(CallbackMode), undefined, false)
catch
CallbackMode ->
loop_callback_mode_result(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent,
CallbackMode, listify(CallbackMode), undefined, false);
Class:Reason:Stacktrace ->
terminate(
Class, Reason, Stacktrace, P, Debug, S, Q)
end;
loop_state_callback(
#params{callback_mode = CallbackMode, modules = [Module | _]} = P,
Debug, S, Q, {State,Data} = State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, {Type,Content}) ->
try
case CallbackMode of
state_functions ->
Module:State(Type, Content, Data);
handle_event_function ->
Module:handle_event(Type, Content, State, Data)
end
of
Result ->
loop_state_callback_result(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, Result)
catch
Result ->
loop_state_callback_result(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, Result);
Class:Reason:Stacktrace ->
terminate(Class, Reason, Stacktrace, P, Debug, S, Q)
end;
loop_state_callback(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, Actions) when is_list(Actions) ->
%% Tunneled actions from enter/8
CallEnter = true,
loop_actions_list(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions).
%% Check the result of Module:callback_mode()
%%
loop_callback_mode_result(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent,
CallbackMode, [H|T], NewCallbackMode, NewStateEnter) ->
%%
case callback_mode(H) of
true ->
loop_callback_mode_result(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent,
CallbackMode, T, H, NewStateEnter);
false ->
case state_enter(H) of
true ->
loop_callback_mode_result(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent,
CallbackMode, T, NewCallbackMode, true);
false ->
terminate(
error,
{bad_return_from_callback_mode,CallbackMode},
?STACKTRACE(),
P, Debug, S, Q)
end
end;
loop_callback_mode_result(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent,
CallbackMode, [], NewCallbackMode, NewStateEnter) ->
%%
case NewCallbackMode of
undefined ->
terminate(
error,
{bad_return_from_callback_mode,CallbackMode},
?STACKTRACE(),
P, Debug, S, Q);
_ ->
P_1 =
P#params{
callback_mode = NewCallbackMode,
state_enter = NewStateEnter},
loop_state_callback(
P_1, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, CallbackEvent)
end.
%% Process the result from the state function
%%
loop_state_callback_result(
P, Debug, S, Q, {State,_Data} = State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
StateCall, Result) ->
%%
case Result of
{next_state,State,NewData} ->
loop_actions(
P, Debug, S, Q, {State,NewData},
NextEventsR, Hibernate, TimeoutsR, Postpone,
false);
{next_state,NextState,NewData}
when StateCall ->
loop_actions(
P, Debug, S, Q, {NextState,NewData},
NextEventsR, Hibernate, TimeoutsR, Postpone,
true);
{next_state,_NextState,_NewData} ->
terminate(
error,
{bad_state_enter_return_from_state_function,Result},
?STACKTRACE(), P, Debug,
S#state{
state_data = State_Data,
hibernate = Hibernate},
Q);
{next_state,State,NewData,Actions} ->
loop_actions(
P, Debug, S, Q, {State,NewData},
NextEventsR, Hibernate, TimeoutsR, Postpone,
false, StateCall, Actions);
{next_state,NextState,NewData,Actions}
when StateCall ->
loop_actions(
P, Debug, S, Q, {NextState,NewData},
NextEventsR, Hibernate, TimeoutsR, Postpone,
true, StateCall, Actions);
{next_state,_NextState,_NewData,_Actions} ->
terminate(
error,
{bad_state_enter_return_from_state_function,Result},
?STACKTRACE(), P, Debug,
S#state{
state_data = State_Data,
hibernate = Hibernate},
Q);
%%
{keep_state,NewData} ->
loop_actions(
P, Debug, S, Q, {State,NewData},
NextEventsR, Hibernate, TimeoutsR, Postpone,
false);
{keep_state,NewData,Actions} ->
loop_actions(
P, Debug, S, Q, {State,NewData},
NextEventsR, Hibernate, TimeoutsR, Postpone,
false, StateCall, Actions);
%%
keep_state_and_data ->
loop_actions(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
false);
{keep_state_and_data,Actions} ->
loop_actions(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
false, StateCall, Actions);
%%
{repeat_state,NewData} ->
loop_actions(
P, Debug, S, Q, {State,NewData},
NextEventsR, Hibernate, TimeoutsR, Postpone,
true);
{repeat_state,NewData,Actions} ->
loop_actions(
P, Debug, S, Q, {State,NewData},
NextEventsR, Hibernate, TimeoutsR, Postpone,
true, StateCall, Actions);
%%
repeat_state_and_data ->
loop_actions(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
true);
{repeat_state_and_data,Actions} ->
loop_actions(
P, Debug, S, Q, State_Data,
NextEventsR, Hibernate, TimeoutsR, Postpone,
true, StateCall, Actions);
%%
stop ->
terminate(
exit, normal, ?STACKTRACE(), P, Debug,
S#state{
state_data = State_Data,
hibernate = Hibernate},
Q);
{stop,Reason} ->
terminate(
exit, Reason, ?STACKTRACE(), P, Debug,
S#state{
state_data = State_Data,
hibernate = Hibernate},
Q);
{stop,Reason,NewData} ->
terminate(
exit, Reason, ?STACKTRACE(), P, Debug,
S#state{
state_data = {State,NewData},
hibernate = Hibernate},
Q);
%%
{stop_and_reply,Reason,Replies} ->
reply_then_terminate(
exit, Reason, ?STACKTRACE(), P, Debug,
S#state{
state_data = State_Data,
hibernate = Hibernate},
Q, Replies);
{stop_and_reply,Reason,Replies,NewData} ->
reply_then_terminate(
exit, Reason, ?STACKTRACE(), P, Debug,
S#state{
state_data = {State,NewData},
hibernate = Hibernate},
Q, Replies);
%%
_ ->
terminate(
error,
{bad_return_from_state_function,Result},
?STACKTRACE(), P, Debug,
S#state{
state_data = State_Data,
hibernate = Hibernate},
Q)
end.
%% Ensure that Actions are a list
%%
loop_actions(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, _StateCall, []) ->
loop_actions(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter);
loop_actions(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions) ->
%%
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, listify(Actions)).
%%
%% Shortcut for no actions
-compile({inline, [loop_actions/10]}).
loop_actions(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter) ->
%%
%% Shortcut for no actions
case CallEnter andalso P#params.state_enter of
true ->
loop_state_enter(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone);
false ->
loop_state_transition(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone)
end.
%% Process the returned actions
%%
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, _StateCall, []) ->
%%
case P#params.state_enter of
true when CallEnter ->
loop_state_enter(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone);
_ ->
loop_state_transition(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone)
end;
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, [Action|Actions]) ->
%%
case Action of
%% Actual actions
{reply,From,Reply} ->
loop_actions_reply(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions,
From, Reply);
%%
%% Actions that set options
{hibernate,Hibernate_1} when is_boolean(Hibernate_1) ->
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate_1, TimeoutsR, Postpone,
CallEnter, StateCall, Actions);
hibernate ->
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, true, TimeoutsR, Postpone,
CallEnter, StateCall, Actions);
%%
{postpone,Postpone_1} when not Postpone_1 orelse StateCall ->
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone_1,
CallEnter, StateCall, Actions);
postpone when StateCall ->
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, true,
CallEnter, StateCall, Actions);
postpone ->
terminate(
error,
{bad_state_enter_action_from_state_function,Action},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q);
%%
{next_event,Type,Content} ->
loop_actions_next_event(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions, Type, Content);
%%
{Tag, NewModule}
when Tag =:= change_callback_module, is_atom(NewModule);
Tag =:= push_callback_module, is_atom(NewModule) ->
if
StateCall ->
NewModules =
case Tag of
change_callback_module ->
[NewModule | tl(P#params.modules)];
push_callback_module ->
[NewModule | P#params.modules]
end,
P_1 =
P#params{
callback_mode = undefined, modules = NewModules},
loop_actions_list(
P_1, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions);
true ->
terminate(
error,
{bad_state_enter_action_from_state_function,Action},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q)
end;
pop_callback_module when tl(P#params.modules) =/= [] ->
if
StateCall ->
NewModules = tl(P#params.modules),
P_1 =
P#params{
callback_mode = undefined,
modules = NewModules},
loop_actions_list(
P_1, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions);
true ->
terminate(
error,
{bad_state_enter_action_from_state_function,Action},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q)
end;
%%
_ ->
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions, Action)
end.
%% Process all other actions, i.e timeout actions,
%% all others are unrecognized
%%
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions,
{TimeoutType,Time,TimeoutMsg,TimeoutOpts} = Timeout) ->
%%
case timeout_event_type(TimeoutType) of
true ->
case listify(TimeoutOpts) of
%% Optimization cases
[{abs,true}] when ?absolute_timeout(Time) ->
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate,
[Timeout|TimeoutsR], Postpone,
CallEnter, StateCall, Actions);
[{abs,false}] when ?relative_timeout(Time) ->
RelativeTimeout = {TimeoutType,Time,TimeoutMsg},
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate,
[RelativeTimeout|TimeoutsR], Postpone,
CallEnter, StateCall, Actions);
[] when ?relative_timeout(Time) ->
RelativeTimeout = {TimeoutType,Time,TimeoutMsg},
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate,
[RelativeTimeout|TimeoutsR], Postpone,
CallEnter, StateCall, Actions);
%% Generic case
TimeoutOptsList ->
case parse_timeout_opts_abs(TimeoutOptsList) of
true when ?absolute_timeout(Time) ->
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate,
[Timeout|TimeoutsR], Postpone,
CallEnter, StateCall, Actions);
false when ?relative_timeout(Time) ->
RelativeTimeout = {TimeoutType,Time,TimeoutMsg},
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate,
[RelativeTimeout|TimeoutsR], Postpone,
CallEnter, StateCall, Actions);
_ ->
terminate(
error,
{bad_action_from_state_function,Timeout},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q)
end
end;
false ->
terminate(
error,
{bad_action_from_state_function,Timeout},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q)
end;
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions,
{TimeoutType,Time,_TimeoutMsg} = Timeout) ->
%%
case timeout_event_type(TimeoutType) of
true
when ?relative_timeout(Time);
Time =:= update ->
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate,
[Timeout|TimeoutsR], Postpone,
CallEnter, StateCall, Actions);
_ ->
terminate(
error,
{bad_action_from_state_function,Timeout},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q)
end;
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions,
{TimeoutType,cancel} = Action) ->
%%
case timeout_event_type(TimeoutType) of
true ->
Timeout = {TimeoutType,infinity,undefined},
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate,
[Timeout|TimeoutsR], Postpone,
CallEnter, StateCall, Actions);
false ->
terminate(
error,
{bad_action_from_state_function,Action},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q)
end;
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions,
Time) ->
%%
if
?relative_timeout(Time) ->
Timeout = {timeout,Time,Time},
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate,
[Timeout|TimeoutsR], Postpone,
CallEnter, StateCall, Actions);
true ->
terminate(
error,
{bad_action_from_state_function,Time},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q)
end.
%% Process a reply action
%%
loop_actions_reply(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions,
From, Reply) ->
%%
case from(From) of
true ->
%% No need for a separate ?not_sys_debug clause here
%% since the external call to erlang:'!'/2 in reply/2
%% will cause swap out of all live registers anyway
reply(From, Reply),
Debug_1 = ?sys_debug(Debug, P#params.name, {out,Reply,From}),
loop_actions_list(
P, Debug_1, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions);
false ->
terminate(
error,
{bad_action_from_state_function,{reply,From,Reply}},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q)
end.
%% Process a next_event action
%%
loop_actions_next_event(
P, Debug, S, Q, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions, Type, Content) ->
case event_type(Type) of
true when StateCall ->
NextEvent = {Type,Content},
case Debug of
?not_sys_debug ->
loop_actions_list(
P, Debug, S, Q, NextState_NewData,
[NextEvent|NextEventsR],
Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions);
_ ->
Name = P#params.name,
{State,_Data} = S#state.state_data,
Debug_1 =
sys_debug(Debug, Name, {in,{Type,Content},State}),
loop_actions_list(
P, Debug_1, S, Q, NextState_NewData,
[NextEvent|NextEventsR],
Hibernate, TimeoutsR, Postpone,
CallEnter, StateCall, Actions)
end;
_ ->
terminate(
error,
{if
StateCall ->
bad_action_from_state_function;
true ->
bad_state_enter_action_from_state_function
end,
{next_event,Type,Content}},
?STACKTRACE(), P, Debug,
S#state{
state_data = NextState_NewData,
hibernate = Hibernate},
Q)
end.
%% Do the state transition
%%
loop_state_transition(
P, Debug, #state{state_data = {State,_Data}, postponed = Postponed} = S,
[Event|Events], {NextState,_NewData} = NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postpone) ->
%%
%% All options have been collected and next_events are buffered.
%% Do the actual state transition.
%%
Postponed_1 = % Move current event to postponed if Postpone
case Postpone of
true ->
[Event|Postponed];
false ->
Postponed
end,
case Debug of
?not_sys_debug ->
%% Optimization for no sys_debug
%% - avoid calling sys_debug/3
if
NextState =:= State ->
loop_keep_state(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed_1);
true ->
loop_state_change(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed_1)
end;
_ ->
%% With sys_debug
Name = P#params.name,
Debug_1 =
case Postpone of
true ->
sys_debug(
Debug, Name,
{postpone,Event,State,NextState});
false ->
sys_debug(
Debug, Name,
{consume,Event,State,NextState})
end,
if
NextState =:= State ->
loop_keep_state(
P, Debug_1, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed_1);
true ->
loop_state_change(
P, Debug_1, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed_1)
end
end.
%% State transition to the same state
%%
loop_keep_state(
P, Debug, #state{timers = Timers} = S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed) ->
%%
%% Cancel event timeout
%%
case Timers of
%% Optimization
%% - only cancel timeout when it is active
%%
#{timeout := {TimerRef,_TimeoutMsg}} ->
%% Event timeout active
loop_next_events(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
cancel_timer(timeout, TimerRef, Timers));
_ ->
%% No event timeout active
loop_next_events(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers)
end.
%% State transition to a different state
%%
loop_state_change(
P, Debug, S, Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed) ->
%%
%% Retry postponed events
%%
case Postponed of
[] ->
loop_state_change(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR);
[E1] ->
loop_state_change(
P, Debug, S,
[E1|Events], NextState_NewData,
NextEventsR, Hibernate, TimeoutsR);
[E2,E1] ->
loop_state_change(
P, Debug, S,
[E1,E2|Events], NextState_NewData,
NextEventsR, Hibernate, TimeoutsR);
[_,_|_] ->
loop_state_change(
P, Debug, S,
lists:reverse(Postponed, Events), NextState_NewData,
NextEventsR, Hibernate, TimeoutsR)
end.
%%
loop_state_change(
P, Debug, #state{timers = Timers} = S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR) ->
%%
%% Cancel state and event timeout
%%
case Timers of
%% Optimization
%% - only cancel timeout when it is active
%%
#{state_timeout := {TimerRef,_TimeoutMsg}} ->
%% State timeout active
%% - cancel event timeout too since it is faster than inspecting
loop_next_events(
P, Debug, S, Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, [],
cancel_timer(
timeout,
cancel_timer(state_timeout, TimerRef, Timers)));
#{timeout := {TimerRef,_TimeoutMsg}} ->
%% Event timeout active but not state timeout
%% - cancel event timeout only
loop_next_events(
P, Debug, S, Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, [],
cancel_timer(timeout, TimerRef, Timers));
_ ->
%% No state nor event timeout active.
loop_next_events(
P, Debug, S, Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, [],
Timers)
end.
%% Continue state transition with processing of
%% timeouts and inserted events
%%
loop_next_events(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, [], Postponed,
Timers) ->
%%
%% Optimization when there are no timeouts
%% hence no zero timeout events to append to Events
%% - avoid loop_timeouts
loop_done(
P, Debug,
S#state{
state_data = NextState_NewData,
postponed = Postponed,
timers = Timers,
hibernate = Hibernate},
Events, NextEventsR);
loop_next_events(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers) ->
%%
Seen = #{},
TimeoutEvents = [],
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents).
%% Continue state transition with processing of timeouts
%% and finally inserted events
%%
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, [], Postponed,
Timers, _Seen, TimeoutEvents) ->
%%
%% End of timeouts
%%
case TimeoutEvents of
[] ->
S_1 =
S#state{
state_data = NextState_NewData,
postponed = Postponed,
timers = Timers,
hibernate = Hibernate},
loop_done(P, Debug, S_1, Events, NextEventsR);
[_|_] ->
#{t0q := T0Q} = Timers,
S_1 =
S#state{
state_data = NextState_NewData,
postponed = Postponed,
timers = Timers#{t0q := T0Q ++ TimeoutEvents},
hibernate = Hibernate},
loop_done(P, Debug, S_1, Events, NextEventsR)
end;
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, [Timeout|TimeoutsR], Postponed,
Timers, Seen, TimeoutEvents) ->
%%
TimeoutType = element(1, Timeout),
case Seen of
#{TimeoutType := _} ->
%% Type seen before - ignore
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents);
#{} ->
case Timeout of
{_,Time,TimeoutMsg} ->
%% Relative timeout or update
loop_timeouts_start(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, Time, TimeoutMsg, []);
{_,Time,TimeoutMsg,TimeoutOpts} ->
%% Absolute timeout
loop_timeouts_start(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, Time, TimeoutMsg, listify(TimeoutOpts))
end
end.
%% Loop helper to start or restart a timeout
%%
loop_timeouts_start(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, Time, TimeoutMsg, TimeoutOpts) ->
%%
case Time of
infinity ->
%% Cancel any running timer
loop_timeouts_cancel(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType);
update ->
loop_timeouts_update(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, TimeoutMsg);
0 ->
%% (Re)start zero timeout
TimerRef = 0,
TimeoutEvents_1 = [TimeoutType | TimeoutEvents],
loop_timeouts_register(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents_1,
TimeoutType, Time, TimeoutMsg, TimeoutOpts, TimerRef);
_ ->
%% (Re)start the timer
TimerRef =
erlang:start_timer(Time, self(), TimeoutType, TimeoutOpts),
loop_timeouts_register(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, Time, TimeoutMsg, TimeoutOpts, TimerRef)
end.
%% Loop helper to register a newly started timer
%% and to cancel any running timer
%%
loop_timeouts_register(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, Time, TimeoutMsg, TimeoutOpts, TimerRef) ->
%%
case Debug of
?not_sys_debug ->
loop_timeouts_register(
P, Debug, S, Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, TimerRef, TimeoutMsg);
_ ->
{State,_Data} = NextState_NewData,
Debug_1 =
sys_debug(
Debug, P#params.name,
{start_timer,
{TimeoutType,Time,TimeoutMsg,TimeoutOpts},
State}),
loop_timeouts_register(
P, Debug_1, S, Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, TimerRef, TimeoutMsg)
end.
%%
loop_timeouts_register(
P, Debug, S, Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, TimerRef, TimeoutMsg) ->
%%
case Timers of
#{TimeoutType := {0,_OldTimeoutMsg},
t0q := T0Q} ->
%% Cancel the running timer,
%% and update timer type and ref
Timers_1 =
Timers
#{TimeoutType := {0,TimeoutMsg},
t0q := lists:delete(TimeoutType, T0Q)},
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers_1, Seen#{TimeoutType => true}, TimeoutEvents);
#{TimeoutType := {OldTimerRef,_OldTimeoutMsg}} ->
%% Cancel the running timer,
%% and update timer type and ref
cancel_timer(OldTimerRef),
Timers_1 = Timers#{TimeoutType := {TimerRef,TimeoutMsg}},
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers_1, Seen#{TimeoutType => true}, TimeoutEvents);
#{} ->
%% Insert the new timer type and ref
Timers_1 = Timers#{TimeoutType => {TimerRef,TimeoutMsg}},
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers_1, Seen#{TimeoutType => true}, TimeoutEvents)
end.
%% Loop helper to cancel a timeout
%%
loop_timeouts_cancel(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents, TimeoutType) ->
%% This function body should have been:
%% Timers_1 = cancel_timer(TimeoutType, Timers),
%% loop_timeouts(
%% P, Debug, S,
%% Events, NextState_NewData,
%% NextEventsR, Hibernate, TimeoutsR, Postponed,
%% Timers_1, Seen#{TimeoutType => true}, TimeoutEvents).
%%
%% Explicitly separate cases to get separate code paths for when
%% the map key exists vs. not, since otherwise the external call
%% to erlang:cancel_timer/1 and to maps:remove/2 within
%% cancel_timer/2 would cause all live registers
%% to be saved to and restored from the stack also for
%% the case when the map key TimeoutType does not exist
case Timers of
#{TimeoutType := {TimerRef,_TimeoutMsg}} ->
Timers_1 = cancel_timer(TimeoutType, TimerRef, Timers),
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers_1, Seen#{TimeoutType => true}, TimeoutEvents);
#{} ->
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen#{TimeoutType => true}, TimeoutEvents)
end.
%% Loop helper to update the timeout message,
%% or start a zero timeout if no timer is running
%%
loop_timeouts_update(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers, Seen, TimeoutEvents,
TimeoutType, TimeoutMsg) ->
%%
case Timers of
#{TimeoutType := {TimerRef,_OldTimeoutMsg}} ->
Timers_1 = Timers#{TimeoutType := {TimerRef,TimeoutMsg}},
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers_1, Seen#{TimeoutType => true},
TimeoutEvents);
#{} ->
Timers_1 = Timers#{TimeoutType => {0, TimeoutMsg}},
TimeoutEvents_1 = [TimeoutType|TimeoutEvents],
loop_timeouts(
P, Debug, S,
Events, NextState_NewData,
NextEventsR, Hibernate, TimeoutsR, Postponed,
Timers_1, Seen#{TimeoutType => true},
TimeoutEvents_1)
end.
%% Place inserted events first in the event queue
%%
loop_done(P, Debug, S, Events, NextEventsR) ->
case NextEventsR of
[] ->
loop_done(P, Debug, S, Events);
[E1] ->
loop_done(P, Debug, S, [E1|Events]);
[E2,E1] ->
loop_done(P, Debug, S, [E1,E2|Events]);
[_,_|_] ->
loop_done(P, Debug, S, lists:reverse(NextEventsR, Events))
end.
%%
%% State transition is done, keep looping if there are
%% enqueued events, or if there are zero timeouts,
%% otherwise get a new event
%%
loop_done(P, Debug, S, Q) ->
%%% io:format(
%%% "loop_done: state_data = ~p,~n"
%%% " postponed = ~p, Q = ~p,~n",
%%% " timers = ~p.~n"
%%% [S#state.state_data,,S#state.postponed,Q,S#state.timers]),
case Q of
[] ->
case S#state.timers of
#{t0q := [TimeoutType|_]} = Timers ->
#{TimeoutType := {0 = TimerRef, TimeoutMsg}} = Timers,
Timers_1 = cancel_timer(TimeoutType, TimerRef, Timers),
S_1 = S#state{timers = Timers_1},
Event = {TimeoutType, TimeoutMsg},
loop_receive_result(P, Debug, S_1, Event);
#{} ->
%% Get a new event
loop(P, Debug, S)
end;
[Event|Events] ->
%% Loop until out of enqueued events
loop_event(P, Debug, S, Event, Events)
end.
%%---------------------------------------------------------------------------
%% Server loop helpers
%% Parse an option list for erlang:start_timer/4 to figure out
%% if the timeout will be absolute or relative
%%
parse_timeout_opts_abs(Opts) ->
parse_timeout_opts_abs(Opts, false).
%%
parse_timeout_opts_abs(Opts, Abs) ->
case Opts of
[] ->
Abs;
[{abs,Abs_1}|Opts] when is_boolean(Abs_1) ->
parse_timeout_opts_abs(Opts, Abs_1);
_ ->
badarg
end.
%%---------------------------------------------------------------------------
%% Server helpers
reply_then_terminate(Class, Reason, Stacktrace, P, Debug, S, Q, Replies) ->
do_reply_then_terminate(
Class, Reason, Stacktrace, P, Debug, S, Q, listify(Replies)).
%%
do_reply_then_terminate(
Class, Reason, Stacktrace, P, Debug, S, Q, []) ->
terminate(Class, Reason, Stacktrace, P, Debug, S, Q);
do_reply_then_terminate(
Class, Reason, Stacktrace, P, Debug, S, Q, [R|Rs]) ->
case R of
{reply,From,Reply} ->
case from(From) of
true ->
reply(From, Reply),
Debug_1 =
?sys_debug(
Debug,
P#params.name,
{out,Reply,From}),
do_reply_then_terminate(
Class, Reason, Stacktrace, P, Debug_1, S, Q, Rs);
false ->
terminate(
error,
{bad_reply_action_from_state_function,R},
?STACKTRACE(),
P, Debug, S, Q)
end;
_ ->
terminate(
error,
{bad_reply_action_from_state_function,R},
?STACKTRACE(),
P, Debug, S, Q)
end.
terminate(
Class, Reason, Stacktrace,
#params{modules = [Module | _]} = P, Debug,
#state{state_data = {State,Data}} = S, Q) ->
case erlang:function_exported(Module, terminate, 3) of
true ->
try Module:terminate(Reason, State, Data) of
_ -> ok
catch
_ -> ok;
C:R:ST ->
error_info(C, R, ST, Debug, P, S, Q),
erlang:raise(C, R, ST)
end;
false ->
ok
end,
_ =
case Reason of
normal ->
terminate_sys_debug(Debug, P, State, Reason);
shutdown ->
terminate_sys_debug(Debug, P, State, Reason);
{shutdown,_} ->
terminate_sys_debug(Debug, P, State, Reason);
_ ->
error_info(Class, Reason, Stacktrace, Debug, P, S, Q)
end,
case Stacktrace of
[] ->
erlang:Class(Reason);
[_|_] ->
erlang:raise(Class, Reason, Stacktrace)
end.
terminate_sys_debug(Debug, P, State, Reason) ->
?sys_debug(Debug, P#params.name, {terminate,Reason,State}).
error_info(
Class, Reason, Stacktrace, Debug,
#params{
name = Name,
modules = Modules,
callback_mode = CallbackMode,
state_enter = StateEnter} = P,
#state{
postponed = Postponed,
timers = Timers} = S,
Q) ->
Log = partisan_sys:get_log(Debug),
?LOG_ERROR(#{label=>{partisan_gen_statem,terminate},
name=>Name,
queue=>Q,
postponed=>Postponed,
modules=>Modules,
callback_mode=>CallbackMode,
state_enter=>StateEnter,
state=>format_status(terminate, get(), P, S),
timeouts=>list_timeouts(Timers),
log=>Log,
reason=>{Class,Reason,Stacktrace},
client_info=>client_stacktrace(Q)},
#{domain=>[otp],
report_cb=>fun partisan_gen_statem:format_log/2,
error_logger=>
#{tag=>error,
report_cb=>fun partisan_gen_statem:format_log/1}}).
client_stacktrace([]) ->
undefined;
client_stacktrace([{{call,{Pid,_Tag}},_Req}|_])
when is_pid(Pid) ->
case partisan:is_local(Pid) of
true ->
case
process_info(
Pid, [current_stacktrace, registered_name]
)
of
undefined ->
{Pid,dead};
[{current_stacktrace, Stacktrace},
{registered_name, []}] ->
{Pid,{Pid,Stacktrace}};
[{current_stacktrace, Stacktrace},
{registered_name, Name}] ->
{Pid,{Name,Stacktrace}}
end;
false ->
{Pid, remote}
end;
client_stacktrace([{{call,{Term,_Tag}},_Req}|_]) ->
try partisan_remote_ref:to_term(Term) of
Pid when is_pid(Pid) ->
case
process_info(
Pid, [current_stacktrace, registered_name]
)
of
undefined ->
{Pid,dead};
[{current_stacktrace, Stacktrace},
{registered_name, []}] ->
{Pid,{Pid,Stacktrace}};
[{current_stacktrace, Stacktrace},
{registered_name, Name}] ->
{Pid,{Name,Stacktrace}}
end;
_ ->
error(function_clause)
catch
error:badarg ->
{Term, remote}
end;
client_stacktrace([_|_]) ->
undefined.
%% format_log/1 is the report callback used by Logger handler
%% error_logger only. It is kept for backwards compatibility with
%% legacy error_logger event handlers. This function must always
%% return {Format,Args} compatible with the arguments in this module's
%% calls to error_logger prior to OTP-21.0.
format_log(Report) ->
Depth = error_logger:get_format_depth(),
FormatOpts = #{chars_limit => unlimited,
depth => Depth,
single_line => false,
encoding => utf8},
format_log_multi(limit_report(Report, Depth), FormatOpts).
limit_report(Report, unlimited) ->
Report;
limit_report(#{label:={partisan_gen_statem,terminate},
queue:=Q,
postponed:=Postponed,
modules:=Modules,
state:=FmtData,
timeouts:=Timeouts,
log:=Log,
reason:={Class,Reason,Stacktrace},
client_info:=ClientInfo}=Report,
Depth) ->
Report#{queue =>
case Q of
[Event|Events] ->
[io_lib:limit_term(Event, Depth)
|io_lib:limit_term(Events, Depth)];
_ -> []
end,
postponed =>
case Postponed of
[] -> [];
_ -> io_lib:limit_term(Postponed, Depth)
end,
modules => io_lib:limit_term(Modules, Depth),
state => io_lib:limit_term(FmtData, Depth),
timeouts =>
case Timeouts of
{0,_} -> Timeouts;
_ -> io_lib:limit_term(Timeouts, Depth)
end,
log =>
case Log of
[] -> [];
_ -> [io_lib:limit_term(T, Depth) || T <- Log]
end,
reason =>
{Class,
io_lib:limit_term(Reason, Depth),
io_lib:limit_term(Stacktrace, Depth)},
client_info => limit_client_info(ClientInfo, Depth)}.
limit_client_info({Pid,{Name,Stacktrace}}, Depth) ->
{Pid,{Name,io_lib:limit_term(Stacktrace, Depth)}};
limit_client_info(Client, _Depth) ->
Client.
%% format_log/2 is the report callback for any Logger handler, except
%% error_logger.
format_log(Report, FormatOpts0) ->
Default = #{chars_limit => unlimited,
depth => unlimited,
single_line => false,
encoding => utf8},
FormatOpts = maps:merge(Default,FormatOpts0),
IoOpts =
case FormatOpts of
#{chars_limit:=unlimited} ->
[];
#{chars_limit:=Limit} ->
[{chars_limit,Limit}]
end,
{Format,Args} = format_log_single(Report, FormatOpts),
io_lib:format(Format, Args, IoOpts).
format_log_single(#{label:={partisan_gen_statem,terminate},
name:=Name,
queue:=Q,
%% postponed
%% callback_mode
%% state_enter
state:=FmtData,
%% timeouts
log:=Log,
reason:={Class,Reason,Stacktrace},
client_info:=ClientInfo},
#{single_line:=true,depth:=Depth}=FormatOpts) ->
P = p(FormatOpts),
{FixedReason,FixedStacktrace} = fix_reason(Class, Reason, Stacktrace),
{ClientFmt,ClientArgs} = format_client_log_single(ClientInfo, P, Depth),
Format =
lists:append(
["State machine ",P," terminating. Reason: ",P,
case FixedStacktrace of
[] -> "";
_ -> ". Stack: "++P
end,
case Q of
[] -> "";
_ -> ". Last event: "++P
end,
". State: ",P,
case Log of
[] -> "";
_ -> ". Log: "++P
end,
"."]),
Args0 =
[Name,FixedReason] ++
case FixedStacktrace of
[] -> [];
_ -> [FixedStacktrace]
end ++
case Q of
[] -> [];
[Event|_] -> [Event]
end ++
[FmtData] ++
case Log of
[] -> [];
_ -> [Log]
end,
Args = case Depth of
unlimited ->
Args0;
_ ->
lists:flatmap(fun(A) -> [A, Depth] end, Args0)
end,
{Format++ClientFmt, Args++ClientArgs};
format_log_single(Report, FormatOpts) ->
format_log_multi(Report, FormatOpts).
format_log_multi(#{label:={partisan_gen_statem,terminate},
name:=Name,
queue:=Q,
postponed:=Postponed,
modules:=Modules,
callback_mode:=CallbackMode,
state_enter:=StateEnter,
state:=FmtData,
timeouts:=Timeouts,
log:=Log,
reason:={Class,Reason,Stacktrace},
client_info:=ClientInfo},
#{depth:=Depth}=FormatOpts) ->
P = p(FormatOpts),
{FixedReason,FixedStacktrace} = fix_reason(Class, Reason, Stacktrace),
{ClientFmt,ClientArgs} = format_client_log(ClientInfo, P, Depth),
CBMode =
case StateEnter of
true ->
[CallbackMode,state_enter];
false ->
CallbackMode
end,
Format =
lists:append(
["** State machine ",P," terminating~n",
case Q of
[] -> "";
_ -> "** Last event = "++P++"~n"
end,
"** When server state = ",P,"~n",
"** Reason for termination = ",P,":",P,"~n",
"** Callback modules = ",P,"~n",
"** Callback mode = ",P,"~n",
case Q of
[_,_|_] -> "** Queued = "++P++"~n";
_ -> ""
end,
case Postponed of
[] -> "";
_ -> "** Postponed = "++P++"~n"
end,
case FixedStacktrace of
[] -> "";
_ -> "** Stacktrace =~n** "++P++"~n"
end,
case Timeouts of
{0,_} -> "";
_ -> "** Time-outs: "++P++"~n"
end,
case Log of
[] -> "";
_ -> "** Log =~n** "++P++"~n"
end]),
Args0 =
[Name |
case Q of
[] -> [];
[Event|_] -> [Event]
end] ++
[FmtData,
Class,FixedReason,
Modules,
CBMode] ++
case Q of
[_|[_|_] = Events] -> [Events];
_ -> []
end ++
case Postponed of
[] -> [];
_ -> [Postponed]
end ++
case FixedStacktrace of
[] -> [];
_ -> [FixedStacktrace]
end ++
case Timeouts of
{0,_} -> [];
_ -> [Timeouts]
end ++
case Log of
[] -> [];
_ -> [Log]
end,
Args = case Depth of
unlimited ->
Args0;
_ ->
lists:flatmap(fun(A) -> [A, Depth] end, Args0)
end,
{Format++ClientFmt,Args++ClientArgs}.
fix_reason(Class, Reason, Stacktrace) ->
case Stacktrace of
[{M,F,Args,_}|ST]
when Class =:= error, Reason =:= undef ->
case code:is_loaded(M) of
false ->
{{'module could not be loaded',M},ST};
_ ->
Arity =
if
is_list(Args) ->
length(Args);
is_integer(Args) ->
Args
end,
case erlang:function_exported(M, F, Arity) of
true ->
{Reason,Stacktrace};
false ->
{{'function not exported',{M,F,Arity}},ST}
end
end;
_ -> {Reason,Stacktrace}
end.
format_client_log_single(undefined, _, _) ->
{"", []};
format_client_log_single({Pid,dead}, _, _) ->
{" Client ~0p is dead.", [Pid]};
format_client_log_single({Pid,remote}, _, _) ->
{" Client ~0p is remote on node ~0p.", [Pid, partisan:node(Pid)]};
format_client_log_single({_Pid,{Name,Stacktrace0}}, P, Depth) ->
%% Minimize the stacktrace a bit for single line reports. This is
%% hopefully enough to point out the position.
Stacktrace = lists:sublist(Stacktrace0, 4),
Format = lists:append([" Client ",P," stacktrace: ",P,"."]),
Args = case Depth of
unlimited ->
[Name, Stacktrace];
_ ->
[Name, Depth, Stacktrace, Depth]
end,
{Format, Args}.
format_client_log(undefined, _, _) ->
{"", []};
format_client_log({Pid,dead}, _, _) ->
{"** Client ~p is dead~n", [Pid]};
format_client_log({Pid,remote}, _, _) ->
{"** Client ~p is remote on node ~p~n", [Pid,partisan:node(Pid)]};
format_client_log({_Pid,{Name,Stacktrace}}, P, Depth) ->
Format = lists:append(["** Client ",P," stacktrace~n** ",P,"~n"]),
Args = case Depth of
unlimited ->
[Name, Stacktrace];
_ ->
[Name, Depth, Stacktrace, Depth]
end,
{Format,Args}.
p(#{single_line:=Single,depth:=Depth,encoding:=Enc}) ->
"~"++single(Single)++mod(Enc)++p(Depth);
p(unlimited) ->
"p";
p(_Depth) ->
"P".
single(true) -> "0";
single(false) -> "".
mod(latin1) -> "";
mod(_) -> "t".
%% Call Module:format_status/2 or return a default value
format_status(
Opt, PDict,
#params{modules = [Module | _]},
#state{state_data = {State,Data} = State_Data}) ->
case erlang:function_exported(Module, format_status, 2) of
true ->
try Module:format_status(Opt, [PDict,State,Data])
catch
Result -> Result;
_:_ ->
format_status_default(
Opt,
{State,
atom_to_list(Module) ++ ":format_status/2 crashed"})
end;
false ->
format_status_default(Opt, State_Data)
end.
%% The default Module:format_status/3
format_status_default(Opt, State_Data) ->
case Opt of
terminate ->
State_Data;
_ ->
[{data,[{"State",State_Data}]}]
end.
-compile({inline, [listify/1]}).
listify(Item) when is_list(Item) ->
Item;
listify(Item) ->
[Item].
-define(
cancel_timer(TimerRef),
case erlang:cancel_timer(TimerRef) of
false ->
%% No timer found and we have not seen the timeout message
receive
{timeout,(TimerRef),_} ->
ok
end;
_ ->
%% Timer was running
ok
end).
%%
%% Cancel erlang: timer and consume timeout message
%%
-compile({inline, [cancel_timer/1]}).
cancel_timer(TimerRef) ->
?cancel_timer(TimerRef).
-define(
cancel_timer(TimeoutType, TimerRef, Timers),
case (TimerRef) of
0 ->
maps:remove(
begin TimeoutType end,
maps:update(
t0q,
lists:delete(
begin TimeoutType end,
maps:get(t0q, begin Timers end)),
begin Timers end));
_ ->
?cancel_timer(TimerRef),
maps:remove(begin TimeoutType end, begin Timers end)
end).
%%
%% Cancel timer and remove from Timers
%%
-compile({inline, [cancel_timer/3]}).
cancel_timer(TimeoutType, TimerRef, Timers) ->
?cancel_timer(TimeoutType, TimerRef, Timers).
%% Cancel timer if running, otherwise no op
%%
%% Remove the timer from Timers
-compile({inline, [cancel_timer/2]}).
cancel_timer(TimeoutType, Timers) ->
case Timers of
#{TimeoutType := {TimerRef, _TimeoutMsg}} ->
?cancel_timer(TimeoutType, TimerRef, Timers);
#{} ->
Timers
end.
%% Return a list of all pending timeouts
list_timeouts(Timers) ->
{maps:size(Timers) - 1, % Subtract fixed key 't0q'
maps:fold(
fun (t0q, _, Acc) ->
Acc;
(TimeoutType, {_TimerRef,TimeoutMsg}, Acc) ->
[{TimeoutType,TimeoutMsg}|Acc]
end, [], Timers)}.
