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-rw-r--r--lib/stdlib/src/gen_statem.erl1682
1 files changed, 1101 insertions, 581 deletions
diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl
index 23bddafeed..b5e9da1e66 100644
--- a/lib/stdlib/src/gen_statem.erl
+++ b/lib/stdlib/src/gen_statem.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 2016. All Rights Reserved.
+%% Copyright Ericsson AB 2016-2017. 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.
@@ -24,7 +24,7 @@
[start/3,start/4,start_link/3,start_link/4,
stop/1,stop/3,
cast/2,call/2,call/3,
- enter_loop/5,enter_loop/6,enter_loop/7,
+ enter_loop/4,enter_loop/5,enter_loop/6,
reply/1,reply/2]).
%% gen callbacks
@@ -44,15 +44,22 @@
-export(
[wakeup_from_hibernate/3]).
-%% Type exports for templates
+%% Type exports for templates and callback modules
-export_type(
[event_type/0,
- callback_mode/0,
- state_function_result/0,
- handle_event_result/0,
+ callback_mode_result/0,
+ init_result/1,
+ state_enter_result/1,
+ event_handler_result/1,
+ reply_action/0,
+ enter_action/0,
action/0]).
+%% Old types, not advertised
+-export_type(
+ [state_function_result/0,
+ handle_event_result/0]).
-%% Fix problem for doc build
+%% Type that is exported just to be documented
-export_type([transition_option/0]).
%%%==========================================================================
@@ -63,21 +70,26 @@
{To :: pid(), Tag :: term()}. % Reply-to specifier for call
-type state() ::
- state_name() | % For state callback function StateName/5
- term(). % For state callback function handle_event/5
+ state_name() | % For StateName/3 callback functions
+ term(). % For handle_event/4 callback function
-type state_name() :: atom().
-type data() :: term().
-type event_type() ::
- {'call',From :: from()} | 'cast' |
- 'info' | 'timeout' | 'internal'.
+ {'call',From :: from()} | 'cast' | 'info' |
+ 'timeout' | {'timeout', Name :: term()} | 'state_timeout' |
+ 'internal'.
+-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().
+ postpone() | hibernate() |
+ event_timeout() | generic_timeout() | state_timeout().
-type postpone() ::
%% If 'true' postpone the current event
%% and retry it when the state changes (=/=)
@@ -86,9 +98,17 @@
%% If 'true' hibernate the server instead of going into receive
boolean().
-type event_timeout() ::
- %% Generate a ('timeout', EventContent, ...) event after Time
+ %% Generate a ('timeout', EventContent, ...) event
%% unless some other event is delivered
- Time :: timeout().
+ 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:
@@ -96,7 +116,7 @@
%% * All action()s are executed in order of apperance.
%% * Postponing the current event is performed
%% iff 'postpone' is 'true'.
- %% * A state timer is started iff 'timeout' is set.
+ %% * 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')
@@ -108,100 +128,153 @@
'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()} |
+ enter_action().
+-type enter_action() ::
'hibernate' | % Set the hibernate option
{'hibernate', Hibernate :: hibernate()} |
%%
(Timeout :: event_timeout()) | % {timeout,Timeout}
- {'timeout', % Set the event timeout option
+ {'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()])} |
%%
- reply_action() |
+ {{'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()])} |
%%
- %% 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()}.
+ {'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()])} |
+ %%
+ reply_action().
-type reply_action() ::
{'reply', % Reply to a caller
From :: from(), Reply :: term()}.
+-type init_result(StateType) ::
+ {ok, State :: StateType, Data :: data()} |
+ {ok, State :: StateType, Data :: data(),
+ Actions :: [action()] | action()} |
+ 'ignore' |
+ {'stop', Reason :: term()}.
+
+%% Old, not advertised
-type state_function_result() ::
- {'next_state', % {next_state,NextStateName,NewData,[]}
- NextStateName :: state_name(),
+ event_handler_result(state_name()).
+-type handle_event_result() ::
+ event_handler_result(state()).
+%%
+-type state_enter_result(State) ::
+ {'next_state', % {next_state,NextState,NewData,[]}
+ State,
NewData :: data()} |
{'next_state', % State transition, maybe to the same state
- NextStateName :: state_name(),
+ State,
NewData :: data(),
- Actions :: [action()] | action()} |
- common_state_callback_result().
--type handle_event_result() ::
+ Actions :: [enter_action()] | enter_action()} |
+ state_callback_result(enter_action()).
+-type event_handler_result(StateType) ::
{'next_state', % {next_state,NextState,NewData,[]}
- NextState :: state(),
+ NextState :: StateType,
NewData :: data()} |
{'next_state', % State transition, maybe to the same state
- NextState :: state(),
+ NextState :: StateType,
NewData :: data(),
Actions :: [action()] | action()} |
- common_state_callback_result().
--type common_state_callback_result() ::
+ state_callback_result(action()).
+-type state_callback_result(ActionType) ::
+ {'keep_state', % {keep_state,NewData,[]}
+ NewData :: data()} |
+ {'keep_state', % Keep state, change data
+ NewData :: data(),
+ 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 :: data()} |
+ {'repeat_state', % Repeat state, change data
+ NewData :: data(),
+ 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 :: data()} |
+ %%
{'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 :: data()} |
- {'keep_state', % {keep_state,NewData,[]}
- NewData :: data()} |
- {'keep_state', % Keep state, change data
- NewData :: data(),
- Actions :: [action()] | action()} |
- 'keep_state_and_data' | % {keep_state_and_data,[]}
- {'keep_state_and_data', % Keep state and data -> only actions
- Actions :: [action()] | action()}.
+ NewData :: data()}.
%% 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()) ->
- {callback_mode(), state(), data()} |
- {callback_mode(), state(), data(), [action()] | action()} |
- 'ignore' |
- {'stop', Reason :: term()}.
+-callback init(Args :: term()) -> init_result(state()).
-%% Example state callback for callback_mode() =:= state_functions
-%% state name 'state_name'.
+%% This callback shall return the callback mode of the callback module.
%%
-%% In this mode all states has to be type state_name() i.e atom().
+%% 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 state callbacks and only state callbacks have arity 5
-%% and that is intended.
+%% 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(
- event_type(),
+ 'enter',
+ OldStateName :: state_name(),
+ Data :: data()) ->
+ state_enter_result('state_name');
+ (event_type(),
EventContent :: term(),
Data :: data()) ->
- state_function_result().
-%%
-%% State callback for callback_mode() =:= handle_event_function.
+ event_handler_result(state_name()).
%%
-%% Note that state callbacks and only state callbacks have arity 5
-%% and that is intended.
+%% State callback for all states
+%% when callback_mode() =:= handle_event_function.
-callback handle_event(
- event_type(),
+ 'enter',
+ OldState :: state(),
+ State, % Current state
+ Data :: data()) ->
+ state_enter_result(State);
+ (event_type(),
EventContent :: term(),
State :: state(), % Current state
Data :: data()) ->
- handle_event_result().
+ event_handler_result(state()).
%% Clean up before the server terminates.
-callback terminate(
@@ -219,9 +292,8 @@
OldState :: state(),
OldData :: data(),
Extra :: term()) ->
- {NewCallbackMode :: callback_mode(),
- NewState :: state(),
- NewData :: data()}.
+ {ok, NewState :: state(), NewData :: data()} |
+ (Reason :: term()).
%% Format the callback module state in some sensible that is
%% often condensed way. For StatusOption =:= 'normal' the perferred
@@ -236,44 +308,41 @@
StatusOption :: 'normal' | 'terminate'.
-optional_callbacks(
- [init/1, % One may use enter_loop/5,6,7 instead
- format_status/2, % Has got a default implementation
+ [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, % Example for callback_mode =:= state_functions:
- %% there has to be a StateName/5 callback function for every StateName.
+ state_name/3, % Example for callback_mode() =:= state_functions:
+ %% there has to be a StateName/3 callback function
+ %% for every StateName in your state machine but the state name
+ %% 'state_name' does of course not have to be used.
%%
- handle_event/4]). % For callback_mode =:= handle_event_function
+ handle_event/4 % For callback_mode() =:= handle_event_function
+ ]).
%% Type validation functions
callback_mode(CallbackMode) ->
case CallbackMode of
- state_functions ->
- true;
- handle_event_function ->
- true;
- _ ->
- false
+ state_functions -> true;
+ handle_event_function -> true;
+ _ -> false
end.
%%
-from({Pid,_}) when is_pid(Pid) ->
- true;
-from(_) ->
- false.
+from({Pid,_}) when is_pid(Pid) -> true;
+from(_) -> false.
%%
event_type({call,From}) ->
from(From);
event_type(Type) ->
case Type of
- cast ->
- true;
- info ->
- true;
- timeout ->
- true;
- internal ->
- true;
- _ ->
- false
+ {call,From} -> from(From);
+ cast -> true;
+ info -> true;
+ timeout -> true;
+ state_timeout -> true;
+ internal -> true;
+ {timeout,_} -> true;
+ _ -> false
end.
@@ -300,9 +369,12 @@ event_type(Type) ->
Dbgs ::
['trace' | 'log' | 'statistics' | 'debug'
| {'logfile', string()}]}.
+-type hibernate_after_opt() ::
+ {'hibernate_after', HibernateAfterTimeout :: timeout()}.
-type start_opt() ::
debug_opt()
| {'timeout', Time :: timeout()}
+ | hibernate_after_opt()
| {'spawn_opt', [proc_lib:spawn_option()]}.
-type start_ret() :: {'ok', pid()} | 'ignore' | {'error', term()}.
@@ -378,53 +450,79 @@ call(ServerRef, Request) ->
-spec call(
ServerRef :: server_ref(),
Request :: term(),
- Timeout :: timeout()) ->
+ Timeout ::
+ timeout() |
+ {'clean_timeout',T :: timeout()} |
+ {'dirty_timeout',T :: timeout()}) ->
Reply :: term().
-call(ServerRef, Request, infinity) ->
- try gen:call(ServerRef, '$gen_call', Request, infinity) of
- {ok,Reply} ->
- Reply
- catch
- Class:Reason ->
- erlang:raise(
- Class,
- {Reason,{?MODULE,call,[ServerRef,Request,infinity]}},
- erlang:get_stacktrace())
- end;
call(ServerRef, Request, Timeout) ->
- %% Call server through proxy process to dodge any late reply
- Ref = make_ref(),
- Self = self(),
- Pid = spawn(
- fun () ->
- Self !
- try gen:call(
- ServerRef, '$gen_call', Request, Timeout) of
- Result ->
- {Ref,Result}
- catch Class:Reason ->
- {Ref,Class,Reason,erlang:get_stacktrace()}
- end
- end),
- Mref = monitor(process, Pid),
- receive
- {Ref,Result} ->
- demonitor(Mref, [flush]),
- case Result of
+ case parse_timeout(Timeout) of
+ {dirty_timeout,T} ->
+ try gen:call(ServerRef, '$gen_call', Request, T) of
{ok,Reply} ->
Reply
+ catch
+ Class:Reason ->
+ erlang:raise(
+ Class,
+ {Reason,{?MODULE,call,[ServerRef,Request,Timeout]}},
+ erlang:get_stacktrace())
+ end;
+ {clean_timeout,T} ->
+ %% Call server through proxy process to dodge any late reply
+ Ref = make_ref(),
+ Self = self(),
+ Pid = spawn(
+ fun () ->
+ Self !
+ try gen:call(
+ ServerRef, '$gen_call', Request, T) of
+ Result ->
+ {Ref,Result}
+ catch Class:Reason ->
+ {Ref,Class,Reason,
+ erlang:get_stacktrace()}
+ end
+ end),
+ Mref = monitor(process, Pid),
+ receive
+ {Ref,Result} ->
+ demonitor(Mref, [flush]),
+ case Result of
+ {ok,Reply} ->
+ Reply
+ end;
+ {Ref,Class,Reason,Stacktrace} ->
+ demonitor(Mref, [flush]),
+ erlang:raise(
+ Class,
+ {Reason,{?MODULE,call,[ServerRef,Request,Timeout]}},
+ Stacktrace);
+ {'DOWN',Mref,_,_,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;
- {Ref,Class,Reason,Stacktrace} ->
- demonitor(Mref, [flush]),
- erlang:raise(
- Class,
- {Reason,{?MODULE,call,[ServerRef,Request,Timeout]}},
- Stacktrace);
- {'DOWN',Mref,_,_,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)
+ Error when is_atom(Error) ->
+ erlang:error(Error, [ServerRef,Request,Timeout])
+ end.
+
+parse_timeout(Timeout) ->
+ case Timeout of
+ {clean_timeout,infinity} ->
+ {dirty_timeout,infinity};
+ {clean_timeout,_} ->
+ Timeout;
+ {dirty_timeout,_} ->
+ Timeout;
+ {_,_} ->
+ %% Be nice and throw a badarg for speling errors
+ badarg;
+ infinity ->
+ {dirty_timeout,infinity};
+ T ->
+ {clean_timeout,T}
end.
%% Reply from a state machine callback to whom awaits in call/2
@@ -449,44 +547,36 @@ reply({To,Tag}, Reply) when is_pid(To) ->
%% 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 :: [debug_opt()],
- CallbackMode :: callback_mode(),
+ Module :: module(), Opts :: [debug_opt() | hibernate_after_opt()],
State :: state(), Data :: data()) ->
no_return().
-enter_loop(Module, Opts, CallbackMode, State, Data) ->
- enter_loop(Module, Opts, CallbackMode, State, Data, self()).
+enter_loop(Module, Opts, State, Data) ->
+ enter_loop(Module, Opts, State, Data, self()).
%%
-spec enter_loop(
- Module :: module(), Opts :: [debug_opt()],
- CallbackMode :: callback_mode(),
+ Module :: module(), Opts :: [debug_opt() | hibernate_after_opt()],
State :: state(), Data :: data(),
Server_or_Actions ::
server_name() | pid() | [action()]) ->
no_return().
-enter_loop(Module, Opts, CallbackMode, State, Data, Server_or_Actions) ->
+enter_loop(Module, Opts, State, Data, Server_or_Actions) ->
if
is_list(Server_or_Actions) ->
- enter_loop(
- Module, Opts, CallbackMode, State, Data,
- self(), Server_or_Actions);
+ enter_loop(Module, Opts, State, Data, self(), Server_or_Actions);
true ->
- enter_loop(
- Module, Opts, CallbackMode, State, Data,
- Server_or_Actions, [])
+ enter_loop(Module, Opts, State, Data, Server_or_Actions, [])
end.
%%
-spec enter_loop(
- Module :: module(), Opts :: [debug_opt()],
- CallbackMode :: callback_mode(),
+ Module :: module(), Opts :: [debug_opt() | hibernate_after_opt()],
State :: state(), Data :: data(),
Server :: server_name() | pid(),
Actions :: [action()] | action()) ->
no_return().
-enter_loop(Module, Opts, CallbackMode, State, Data, Server, Actions) ->
+enter_loop(Module, Opts, State, Data, Server, Actions) ->
is_atom(Module) orelse error({atom,Module}),
- callback_mode(CallbackMode) orelse error({callback_mode,CallbackMode}),
Parent = gen:get_parent(),
- enter(Module, Opts, CallbackMode, State, Data, Server, Actions, Parent).
+ enter(Module, Opts, State, Data, Server, Actions, Parent).
%%---------------------------------------------------------------------------
%% API helpers
@@ -514,12 +604,14 @@ send(Proc, Msg) ->
end.
%% Here the init_it/6 and enter_loop/5,6,7 functions converge
-enter(Module, Opts, CallbackMode, State, Data, Server, Actions, Parent) ->
+enter(Module, Opts, State, Data, Server, Actions, Parent) ->
%% The values should already have been type checked
Name = gen:get_proc_name(Server),
Debug = gen:debug_options(Name, Opts),
- P = Events = [],
- Event = {internal,initial_state},
+ HibernateAfterTimeout = gen:hibernate_after(Opts),
+ Events = [],
+ P = [],
+ Event = {internal,init_state},
%% We enforce {postpone,false} to ensure that
%% our fake Event gets discarded, thought it might get logged
NewActions =
@@ -529,21 +621,51 @@ enter(Module, Opts, CallbackMode, State, Data, Server, Actions, Parent) ->
true ->
[Actions,{postpone,false}]
end,
+ TimerRefs = #{},
+ %% Key: timer ref
+ %% Value: the timer type i.e the timer's event type
+ %%
+ TimerTypes = #{},
+ %% Key: timer type i.e the timer's event type
+ %% Value: timer ref
+ %%
+ %% We add a timer to both timer_refs and timer_types
+ %% when we start it. When we request an asynchronous
+ %% timer cancel we remove it from timer_types. When
+ %% the timer cancel message arrives we remove it from
+ %% timer_refs.
+ %%
+ Hibernate = false,
+ CancelTimers = 0,
S = #{
- callback_mode => CallbackMode,
+ callback_mode => undefined,
+ state_enter => false,
module => Module,
name => Name,
- %% All fields below will be replaced according to the arguments to
- %% loop_event_actions/10 when it finally loops back to loop/3
state => State,
data => Data,
postponed => P,
- hibernate => false,
- timer => undefined},
+ %%
+ %% The following fields are finally set from to the arguments to
+ %% loop_event_actions/9 when it finally loops back to loop/3
+ %% in loop_event_result/11
+ timer_refs => TimerRefs,
+ timer_types => TimerTypes,
+ hibernate => Hibernate,
+ hibernate_after => HibernateAfterTimeout,
+ cancel_timers => CancelTimers
+ },
NewDebug = sys_debug(Debug, S, State, {enter,Event,State}),
- loop_event_actions(
- Parent, NewDebug, S, Events,
- State, Data, P, Event, State, NewActions).
+ case call_callback_mode(S) of
+ {ok,NewS} ->
+ loop_event_actions(
+ Parent, NewDebug, NewS,
+ Events, Event, State, Data, NewActions, true);
+ {Class,Reason,Stacktrace} ->
+ terminate(
+ Class, Reason, Stacktrace, NewDebug,
+ S, [Event|Events])
+ end.
%%%==========================================================================
%%% gen callbacks
@@ -558,9 +680,17 @@ init_it(Starter, Parent, ServerRef, Module, Args, Opts) ->
Result ->
init_result(Starter, Parent, ServerRef, Module, Result, Opts);
Class:Reason ->
+ Stacktrace = erlang:get_stacktrace(),
+ Name = gen:get_proc_name(ServerRef),
gen:unregister_name(ServerRef),
proc_lib:init_ack(Starter, {error,Reason}),
- erlang:raise(Class, Reason, erlang:get_stacktrace())
+ error_info(
+ Class, Reason, Stacktrace,
+ #{name => Name,
+ callback_mode => undefined,
+ state_enter => false},
+ [], [], undefined),
+ erlang:raise(Class, Reason, Stacktrace)
end.
%%---------------------------------------------------------------------------
@@ -568,30 +698,12 @@ init_it(Starter, Parent, ServerRef, Module, Args, Opts) ->
init_result(Starter, Parent, ServerRef, Module, Result, Opts) ->
case Result of
- {CallbackMode,State,Data} ->
- case callback_mode(CallbackMode) of
- true ->
- proc_lib:init_ack(Starter, {ok,self()}),
- enter(
- Module, Opts, CallbackMode, State, Data,
- ServerRef, [], Parent);
- false ->
- Error = {callback_mode,CallbackMode},
- proc_lib:init_ack(Starter, {error,Error}),
- exit(Error)
- end;
- {CallbackMode,State,Data,Actions} ->
- case callback_mode(CallbackMode) of
- true ->
- proc_lib:init_ack(Starter, {ok,self()}),
- enter(
- Module, Opts, CallbackMode, State, Data,
- ServerRef, Actions, Parent);
- false ->
- Error = {callback_mode,CallbackMode},
- proc_lib:init_ack(Starter, {error,Error}),
- exit(Error)
- end;
+ {ok,State,Data} ->
+ proc_lib:init_ack(Starter, {ok,self()}),
+ enter(Module, Opts, State, Data, ServerRef, [], Parent);
+ {ok,State,Data,Actions} ->
+ proc_lib:init_ack(Starter, {ok,self()}),
+ enter(Module, Opts, State, Data, ServerRef, Actions, Parent);
{stop,Reason} ->
gen:unregister_name(ServerRef),
proc_lib:init_ack(Starter, {error,Reason}),
@@ -601,8 +713,16 @@ init_result(Starter, Parent, ServerRef, Module, Result, Opts) ->
proc_lib:init_ack(Starter, ignore),
exit(normal);
_ ->
- Error = {bad_return_value,Result},
+ Name = gen:get_proc_name(ServerRef),
+ gen:unregister_name(ServerRef),
+ Error = {bad_return_from_init,Result},
proc_lib:init_ack(Starter, {error,Error}),
+ error_info(
+ error, Error, ?STACKTRACE(),
+ #{name => Name,
+ callback_mode => undefined,
+ state_enter => false},
+ [], [], undefined),
exit(Error)
end.
@@ -612,12 +732,8 @@ init_result(Starter, Parent, ServerRef, Module, Result, Opts) ->
system_continue(Parent, Debug, S) ->
loop(Parent, Debug, S).
-system_terminate(
- Reason, _Parent, Debug,
- #{state := State, data := Data, postponed := P} = S) ->
- terminate(
- exit, Reason, ?STACKTRACE(),
- Debug, S, [], State, Data, P).
+system_terminate(Reason, _Parent, Debug, S) ->
+ terminate(exit, Reason, ?STACKTRACE(), Debug, S, []).
system_code_change(
#{module := Module,
@@ -630,11 +746,9 @@ system_code_change(
Result -> Result
end
of
- {NewCallbackMode,NewState,NewData} ->
- callback_mode(NewCallbackMode) orelse
- error({callback_mode,NewCallbackMode}),
+ {ok,NewState,NewData} ->
{ok,
- S#{callback_mode := NewCallbackMode,
+ S#{callback_mode := undefined,
state := NewState,
data := NewData}};
{ok,_} = Error ->
@@ -656,7 +770,7 @@ system_replace_state(
format_status(
Opt,
[PDict,SysState,Parent,Debug,
- #{name := Name, postponed := P, state := State, data := Data} = S]) ->
+ #{name := Name, postponed := P} = S]) ->
Header = gen:format_status_header("Status for state machine", Name),
Log = sys:get_debug(log, Debug, []),
[{header,Header},
@@ -665,7 +779,7 @@ format_status(
{"Parent",Parent},
{"Logged Events",Log},
{"Postponed",P}]} |
- case format_status(Opt, PDict, S, State, Data) of
+ case format_status(Opt, PDict, S) of
L when is_list(L) -> L;
T -> [T]
end].
@@ -675,14 +789,18 @@ format_status(
%% them, not as the real erlang messages. Use trace for that.
%%---------------------------------------------------------------------------
-print_event(Dev, {in,Event}, {Name,_}) ->
+print_event(Dev, {in,Event}, {Name,State}) ->
+ io:format(
+ Dev, "*DBG* ~p receive ~s in state ~p~n",
+ [Name,event_string(Event),State]);
+print_event(Dev, {out,Reply,{To,_Tag}}, {Name,State}) ->
io:format(
- Dev, "*DBG* ~p received ~s~n",
- [Name,event_string(Event)]);
-print_event(Dev, {out,Reply,{To,_Tag}}, {Name,_}) ->
+ Dev, "*DBG* ~p send ~p to ~p from state ~p~n",
+ [Name,Reply,To,State]);
+print_event(Dev, {terminate,Reason}, {Name,State}) ->
io:format(
- Dev, "*DBG* ~p sent ~p to ~p~n",
- [Name,Reply,To]);
+ Dev, "*DBG* ~p terminate ~p in state ~p~n",
+ [Name,Reason,State]);
print_event(Dev, {Tag,Event,NextState}, {Name,State}) ->
StateString =
case NextState of
@@ -726,22 +844,22 @@ wakeup_from_hibernate(Parent, Debug, S) ->
%% and detours through sys:handle_system_message/7 and proc_lib:hibernate/3
%% Entry point for system_continue/3
-loop(Parent, Debug, #{hibernate := Hibernate} = S) ->
- case Hibernate of
- true ->
- %% Does not return but restarts process at
- %% wakeup_from_hibernate/3 that jumps to loop_receive/3
- proc_lib:hibernate(
- ?MODULE, wakeup_from_hibernate, [Parent,Debug,S]),
- error(
- {should_not_have_arrived_here_but_instead_in,
- {wakeup_from_hibernate,3}});
- false ->
- loop_receive(Parent, Debug, S)
- end.
+loop(Parent, Debug, #{hibernate := true, cancel_timers := 0} = S) ->
+ loop_hibernate(Parent, Debug, S);
+loop(Parent, Debug, S) ->
+ loop_receive(Parent, Debug, S).
+
+loop_hibernate(Parent, Debug, S) ->
+ %% Does not return but restarts process at
+ %% wakeup_from_hibernate/3 that jumps to loop_receive/3
+ proc_lib:hibernate(
+ ?MODULE, wakeup_from_hibernate, [Parent,Debug,S]),
+ error(
+ {should_not_have_arrived_here_but_instead_in,
+ {wakeup_from_hibernate,3}}).
%% Entry point for wakeup_from_hibernate/3
-loop_receive(Parent, Debug, #{timer := Timer} = S) ->
+loop_receive(Parent, Debug, #{hibernate_after := HibernateAfterTimeout} = S) ->
receive
Msg ->
case Msg of
@@ -750,36 +868,87 @@ loop_receive(Parent, Debug, #{timer := Timer} = S) ->
%% Does not return but tail recursively calls
%% system_continue/3 that jumps to loop/3
sys:handle_system_msg(
- Req, Pid, Parent, ?MODULE, Debug, S, Hibernate);
+ Req, Pid, Parent, ?MODULE, Debug, S,
+ Hibernate);
{'EXIT',Parent,Reason} = EXIT ->
- #{state := State, data := Data, postponed := P} = S,
- %% EXIT is not a 2-tuple and therefore
- %% not an event and has no event_type(),
- %% but this will stand out in the crash report...
- terminate(
- exit, Reason, ?STACKTRACE(),
- Debug, S, [EXIT], State, Data, P);
- {timeout,Timer,Content} when Timer =/= undefined ->
- loop_receive_result(
- Parent, Debug, S, {timeout,Content});
- _ ->
- %% Cancel Timer if running
- case Timer of
- undefined ->
- ok;
+ %% EXIT is not a 2-tuple therefore
+ %% not an event but this will stand out
+ %% in the crash report...
+ Q = [EXIT],
+ terminate(exit, Reason, ?STACKTRACE(), Debug, S, Q);
+ {timeout,TimerRef,TimerMsg} ->
+ #{timer_refs := TimerRefs,
+ timer_types := TimerTypes,
+ hibernate := Hibernate} = S,
+ case TimerRefs of
+ #{TimerRef := TimerType} ->
+ %% We know of this timer; is it a running
+ %% timer or a timer being cancelled that
+ %% managed to send a late timeout message?
+ case TimerTypes of
+ #{TimerType := TimerRef} ->
+ %% The timer type maps back to this
+ %% timer ref, so it was a running timer
+ Event = {TimerType,TimerMsg},
+ %% Unregister the triggered timeout
+ NewTimerRefs =
+ maps:remove(TimerRef, TimerRefs),
+ NewTimerTypes =
+ maps:remove(TimerType, TimerTypes),
+ loop_receive_result(
+ Parent, Debug,
+ S#{
+ timer_refs := NewTimerRefs,
+ timer_types := NewTimerTypes},
+ Hibernate,
+ Event);
+ _ ->
+ %% This was a late timeout message
+ %% from timer being cancelled, so
+ %% ignore it and expect a cancel_timer
+ %% msg shortly
+ loop_receive(Parent, Debug, S)
+ end;
+ _ ->
+ %% Not our timer; present it as an event
+ Event = {info,Msg},
+ loop_receive_result(
+ Parent, Debug, S, Hibernate, Event)
+ end;
+ {cancel_timer,TimerRef,_} ->
+ #{timer_refs := TimerRefs,
+ cancel_timers := CancelTimers,
+ hibernate := Hibernate} = S,
+ case TimerRefs of
+ #{TimerRef := _} ->
+ %% We must have requested a cancel
+ %% of this timer so it is already
+ %% removed from TimerTypes
+ NewTimerRefs =
+ maps:remove(TimerRef, TimerRefs),
+ NewCancelTimers = CancelTimers - 1,
+ NewS =
+ S#{
+ timer_refs := NewTimerRefs,
+ cancel_timers := NewCancelTimers},
+ if
+ Hibernate =:= true, NewCancelTimers =:= 0 ->
+ %% No more cancel_timer msgs to expect;
+ %% we can hibernate
+ loop_hibernate(Parent, Debug, NewS);
+ NewCancelTimers >= 0 -> % Assert
+ loop_receive(Parent, Debug, NewS)
+ end;
_ ->
- case erlang:cancel_timer(Timer) of
- TimeLeft when is_integer(TimeLeft) ->
- ok;
- false ->
- receive
- {timeout,Timer,_} ->
- ok
- after 0 ->
- ok
- end
- end
- end,
+ %% Not our cancel_timer msg;
+ %% present it as an event
+ Event = {info,Msg},
+ loop_receive_result(
+ Parent, Debug, S, Hibernate, Event)
+ end;
+ _ ->
+ %% External msg
+ #{hibernate := Hibernate} = S,
Event =
case Msg of
{'$gen_call',From,Request} ->
@@ -789,388 +958,690 @@ loop_receive(Parent, Debug, #{timer := Timer} = S) ->
_ ->
{info,Msg}
end,
- loop_receive_result(Parent, Debug, S, Event)
+ loop_receive_result(
+ Parent, Debug, S, Hibernate, Event)
end
+ after
+ HibernateAfterTimeout ->
+ loop_hibernate(Parent, Debug, S)
end.
loop_receive_result(
Parent, Debug,
#{state := State,
- data := Data,
- postponed := P} = S,
- Event) ->
- %% The engine state map S is now dismantled
- %% and will not be restored until we return to loop/3.
- %%
- %% The fields 'callback_mode', 'module', and 'name' are still valid.
- %% The fields 'state', 'data', and 'postponed' are held in arguments.
- %% The fields 'timer' and 'hibernate' will be recalculated.
- %%
+ timer_types := TimerTypes, cancel_timers := CancelTimers} = S,
+ Hibernate, Event) ->
+ %% From now the 'hibernate' field in S is invalid
+ %% and will be restored when looping back
+ %% in loop_event_result/11
NewDebug = sys_debug(Debug, S, State, {in,Event}),
- %% Here the queue of not yet handled events is created
+ %% Here is the queue of not yet handled events created
Events = [],
- Hibernate = false,
- loop_event(
- Parent, NewDebug, S, Events, State, Data, P, Event, Hibernate).
-
-%% Process the event queue, or if it is empty
-%% loop back to loop/3 to receive a new event
-loop_events(
- Parent, Debug, S, [Event|Events],
- State, Data, P, Hibernate, _Timeout) ->
- %%
- %% If there was a state timer requested we just ignore that
- %% since we have events to handle which cancels the timer
- loop_event(
- Parent, Debug, S, Events, State, Data, P, Event, Hibernate);
-loop_events(
- Parent, Debug, S, [],
- State, Data, P, Hibernate, Timeout) ->
- case Timeout of
- {timeout,0,EventContent} ->
- %% Immediate timeout - simulate it
- %% so we do not get the timeout message
- %% after any received event
- loop_event(
- Parent, Debug, S, [],
- State, Data, P, {timeout,EventContent}, Hibernate);
- {timeout,Time,EventContent} ->
- %% Actually start a timer
- Timer = erlang:start_timer(Time, self(), EventContent),
- loop_events_done(
- Parent, Debug, S, Timer, State, Data, P, Hibernate);
- undefined ->
- %% No state timeout has been requested
- Timer = undefined,
- loop_events_done(
- Parent, Debug, S, Timer, State, Data, P, Hibernate)
+ %% Cancel any running event timer
+ case
+ cancel_timer_by_type(timeout, TimerTypes, CancelTimers)
+ of
+ {_,CancelTimers} ->
+ %% No timer cancelled
+ loop_event(Parent, NewDebug, S, Events, Event, Hibernate);
+ {NewTimerTypes,NewCancelTimers} ->
+ %% The timer is removed from NewTimerTypes but
+ %% remains in TimerRefs until we get
+ %% the cancel_timer msg
+ NewS =
+ S#{
+ timer_types := NewTimerTypes,
+ cancel_timers := NewCancelTimers},
+ loop_event(Parent, NewDebug, NewS, Events, Event, Hibernate)
end.
-%%
-loop_events_done(Parent, Debug, S, Timer, State, Data, P, Hibernate) ->
- NewS =
- S#{
- state := State,
- data := Data,
- postponed := P,
- hibernate := Hibernate,
- timer := Timer},
- loop(Parent, Debug, NewS).
+%% Entry point for handling an event, received or enqueued
loop_event(
Parent, Debug,
- #{callback_mode := CallbackMode,
- module := Module} = S,
- Events,
- State, Data, P, {Type,Content} = Event, Hibernate) ->
+ #{state := State, data := Data} = S,
+ Events, {Type,Content} = Event, Hibernate) ->
%%
- %% If Hibernate is true here it can only be
+ %% 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 depend on i.e collect garbage which
+ %% 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
Hibernate andalso garbage_collect(),
+ case call_state_function(S, Type, Content, State, Data) of
+ {ok,Result,NewS} ->
+ {NextState,NewData,Actions,EnterCall} =
+ parse_event_result(
+ true, Debug, NewS,
+ Events, Event, State, Data, Result),
+ loop_event_actions(
+ Parent, Debug, NewS,
+ Events, Event, NextState, NewData, Actions, EnterCall);
+ {Class,Reason,Stacktrace} ->
+ terminate(
+ Class, Reason, Stacktrace, Debug, S,
+ [Event|Events])
+ end.
+
+loop_event_actions(
+ Parent, Debug,
+ #{state := State, state_enter := StateEnter} = S,
+ Events, Event, NextState, NewData,
+ Actions, EnterCall) ->
+ %% Hibernate is reborn here as false being
+ %% the default value from parse_actions/4
+ case parse_actions(Debug, S, State, Actions) of
+ {ok,NewDebug,Hibernate,TimeoutsR,Postpone,NextEventsR} ->
+ if
+ StateEnter, EnterCall ->
+ loop_event_enter(
+ Parent, NewDebug, S,
+ Events, Event, NextState, NewData,
+ Hibernate, TimeoutsR, Postpone, NextEventsR);
+ true ->
+ loop_event_result(
+ Parent, NewDebug, S,
+ Events, Event, NextState, NewData,
+ Hibernate, TimeoutsR, Postpone, NextEventsR)
+ end;
+ {Class,Reason,Stacktrace} ->
+ terminate(
+ Class, Reason, Stacktrace, Debug, S,
+ [Event|Events])
+ end.
+
+loop_event_enter(
+ Parent, Debug, #{state := State} = S,
+ Events, Event, NextState, NewData,
+ Hibernate, TimeoutsR, Postpone, NextEventsR) ->
+ case call_state_function(S, enter, State, NextState, NewData) of
+ {ok,Result,NewS} ->
+ case parse_event_result(
+ false, Debug, NewS,
+ Events, Event, NextState, NewData, Result) of
+ {_,NewerData,Actions,EnterCall} ->
+ loop_event_enter_actions(
+ Parent, Debug, NewS,
+ Events, Event, NextState, NewerData,
+ Hibernate, TimeoutsR, Postpone, NextEventsR,
+ Actions, EnterCall)
+ end;
+ {Class,Reason,Stacktrace} ->
+ terminate(
+ Class, Reason, Stacktrace, Debug,
+ S#{
+ state := NextState,
+ data := NewData,
+ hibernate := Hibernate},
+ [Event|Events])
+ end.
+
+loop_event_enter_actions(
+ Parent, Debug, #{state_enter := StateEnter} = S,
+ Events, Event, NextState, NewData,
+ Hibernate, TimeoutsR, Postpone, NextEventsR,
+ Actions, EnterCall) ->
+ case
+ parse_enter_actions(
+ Debug, S, NextState, Actions, Hibernate, TimeoutsR)
+ of
+ {ok,NewDebug,NewHibernate,NewTimeoutsR,_,_} ->
+ if
+ StateEnter, EnterCall ->
+ loop_event_enter(
+ Parent, NewDebug, S,
+ Events, Event, NextState, NewData,
+ NewHibernate, NewTimeoutsR, Postpone, NextEventsR);
+ true ->
+ loop_event_result(
+ Parent, NewDebug, S,
+ Events, Event, NextState, NewData,
+ NewHibernate, NewTimeoutsR, Postpone, NextEventsR)
+ end;
+ {Class,Reason,Stacktrace} ->
+ terminate(
+ Class, Reason, Stacktrace, Debug,
+ S#{
+ state := NextState,
+ data := NewData,
+ hibernate := Hibernate},
+ [Event|Events])
+ end.
+
+loop_event_result(
+ Parent, Debug_0,
+ #{state := State, postponed := P_0,
+ timer_refs := TimerRefs_0, timer_types := TimerTypes_0,
+ cancel_timers := CancelTimers_0} = S_0,
+ Events_0, Event_0, NextState, NewData,
+ Hibernate, TimeoutsR, Postpone, NextEventsR) ->
%%
+ %% All options have been collected and next_events are buffered.
+ %% Do the actual state transition.
+ %%
+ {Debug_1,P_1} = % Move current event to postponed if Postpone
+ case Postpone of
+ true ->
+ {sys_debug(Debug_0, S_0, State, {postpone,Event_0,State}),
+ [Event_0|P_0]};
+ false ->
+ {sys_debug(Debug_0, S_0, State, {consume,Event_0,State}),
+ P_0}
+ end,
+ {Events_1,P_2,{TimerTypes_1,CancelTimers_1}} =
+ %% Move all postponed events to queue and cancel the
+ %% state timeout if the state changes
+ if
+ NextState =:= State ->
+ {Events_0,P_1,{TimerTypes_0,CancelTimers_0}};
+ true ->
+ {lists:reverse(P_1, Events_0),
+ [],
+ cancel_timer_by_type(
+ state_timeout, TimerTypes_0, CancelTimers_0)}
+ %% The state timer is removed from TimerTypes_1
+ %% but remains in TimerRefs_0 until we get
+ %% the cancel_timer msg
+ end,
+ {TimerRefs_2,TimerTypes_2,CancelTimers_2,TimeoutEvents} =
+ %% Stop and start non-event timers
+ parse_timers(TimerRefs_0, TimerTypes_1, CancelTimers_1, TimeoutsR),
+ %% Place next events last in reversed queue
+ Events_2R = lists:reverse(Events_1, NextEventsR),
+ %% Enqueue immediate timeout events and start event timer
+ Events_3R = prepend_timeout_events(TimeoutEvents, Events_2R),
+ S_1 =
+ S_0#{
+ state := NextState,
+ data := NewData,
+ postponed := P_2,
+ timer_refs := TimerRefs_2,
+ timer_types := TimerTypes_2,
+ cancel_timers := CancelTimers_2,
+ hibernate := Hibernate},
+ case lists:reverse(Events_3R) of
+ [] ->
+ %% Get a new event
+ loop(Parent, Debug_1, S_1);
+ [Event|Events] ->
+ %% Loop until out of enqueued events
+ loop_event(Parent, Debug_1, S_1, Events, Event, Hibernate)
+ end.
+
+
+%%---------------------------------------------------------------------------
+%% Server loop helpers
+
+call_callback_mode(#{module := Module} = S) ->
+ try Module:callback_mode() of
+ CallbackMode ->
+ callback_mode_result(S, CallbackMode)
+ catch
+ CallbackMode ->
+ callback_mode_result(S, CallbackMode);
+ Class:Reason ->
+ {Class,Reason,erlang:get_stacktrace()}
+ end.
+
+callback_mode_result(S, CallbackMode) ->
+ case
+ parse_callback_mode(
+ if
+ is_atom(CallbackMode) ->
+ [CallbackMode];
+ true ->
+ CallbackMode
+ end, undefined, false)
+ of
+ {undefined,_} ->
+ {error,
+ {bad_return_from_callback_mode,CallbackMode},
+ ?STACKTRACE()};
+ {CBMode,StateEnter} ->
+ {ok,
+ S#{
+ callback_mode := CBMode,
+ state_enter := StateEnter}}
+ end.
+
+parse_callback_mode([], CBMode, StateEnter) ->
+ {CBMode,StateEnter};
+parse_callback_mode([H|T], CBMode, StateEnter) ->
+ case callback_mode(H) of
+ true ->
+ parse_callback_mode(T, H, StateEnter);
+ false ->
+ case H of
+ state_enter ->
+ parse_callback_mode(T, CBMode, true);
+ _ ->
+ {undefined,StateEnter}
+ end
+ end;
+parse_callback_mode(_, _CBMode, StateEnter) ->
+ {undefined,StateEnter}.
+
+
+call_state_function(
+ #{callback_mode := undefined} = S, Type, Content, State, Data) ->
+ case call_callback_mode(S) of
+ {ok,NewS} ->
+ call_state_function(NewS, Type, Content, State, Data);
+ Error ->
+ Error
+ end;
+call_state_function(
+ #{callback_mode := CallbackMode, module := Module} = S,
+ Type, Content, State, Data) ->
try
case CallbackMode of
state_functions ->
Module:State(Type, Content, Data);
handle_event_function ->
Module:handle_event(Type, Content, State, Data)
- end of
+ end
+ of
Result ->
- loop_event_result(
- Parent, Debug, S, Events, State, Data, P, Event, Result)
+ {ok,Result,S}
catch
Result ->
- loop_event_result(
- Parent, Debug, S, Events, State, Data, P, Event, Result);
- error:badarg when CallbackMode =:= state_functions ->
- case erlang:get_stacktrace() of
- [{erlang,apply,[Module,State,_],_}|Stacktrace] ->
- Args = [Type,Content,Data],
- terminate(
- error,
- {undef_state_function,{Module,State,Args}},
- Stacktrace,
- Debug, S, [Event|Events], State, Data, P);
- Stacktrace ->
- terminate(
- error, badarg, Stacktrace,
- Debug, S, [Event|Events], State, Data, P)
- end;
- error:undef ->
- %% Process an undef to check for the simple mistake
- %% of calling a nonexistent state function
- case erlang:get_stacktrace() of
- [{Module,State,
- [Type,Content,Data]=Args,
- _}
- |Stacktrace]
- when CallbackMode =:= state_functions ->
- terminate(
- error,
- {undef_state_function,{Module,State,Args}},
- Stacktrace,
- Debug, S, [Event|Events], State, Data, P);
- [{Module,handle_event,
- [Type,Content,State,Data]=Args,
- _}
- |Stacktrace]
- when CallbackMode =:= handle_event_function ->
- terminate(
- error,
- {undef_state_function,{Module,handle_event,Args}},
- Stacktrace,
- Debug, S, [Event|Events], State, Data, P);
- Stacktrace ->
- terminate(
- error, undef, Stacktrace,
- Debug, S, [Event|Events], State, Data, P)
- end;
+ {ok,Result,S};
Class:Reason ->
- Stacktrace = erlang:get_stacktrace(),
- terminate(
- Class, Reason, Stacktrace,
- Debug, S, [Event|Events], State, Data, P)
+ {Class,Reason,erlang:get_stacktrace()}
end.
+
%% Interpret all callback return variants
-loop_event_result(
- Parent, Debug, S, Events, State, Data, P, Event, Result) ->
+parse_event_result(
+ AllowStateChange, Debug, S,
+ Events, Event, State, Data, Result) ->
case Result of
stop ->
terminate(
- exit, normal, ?STACKTRACE(),
- Debug, S, [Event|Events], State, Data, P);
+ exit, normal, ?STACKTRACE(), Debug,
+ S#{state := State, data := Data},
+ [Event|Events]);
{stop,Reason} ->
terminate(
- exit, Reason, ?STACKTRACE(),
- Debug, S, [Event|Events], State, Data, P);
+ exit, Reason, ?STACKTRACE(), Debug,
+ S#{state := State, data := Data},
+ [Event|Events]);
{stop,Reason,NewData} ->
terminate(
- exit, Reason, ?STACKTRACE(),
- Debug, S, [Event|Events], State, NewData, P);
+ exit, Reason, ?STACKTRACE(), Debug,
+ S#{state := State, data := NewData},
+ [Event|Events]);
+ %%
{stop_and_reply,Reason,Replies} ->
- Q = [Event|Events],
reply_then_terminate(
- exit, Reason, ?STACKTRACE(),
- Debug, S, Q, State, Data, P, Replies);
+ exit, Reason, ?STACKTRACE(), Debug,
+ S#{state := State, data := Data},
+ [Event|Events], Replies);
{stop_and_reply,Reason,Replies,NewData} ->
- Q = [Event|Events],
reply_then_terminate(
- exit, Reason, ?STACKTRACE(),
- Debug, S, Q, State, NewData, P, Replies);
- {next_state,NextState,NewData} ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, []);
- {next_state,NextState,NewData,Actions} ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions);
+ exit, Reason, ?STACKTRACE(), Debug,
+ S#{state := State, data := NewData},
+ [Event|Events], Replies);
+ %%
+ {next_state,State,NewData} ->
+ {State,NewData,[],false};
+ {next_state,NextState,NewData} when AllowStateChange ->
+ {NextState,NewData,[],true};
+ {next_state,State,NewData,Actions} ->
+ {State,NewData,Actions,false};
+ {next_state,NextState,NewData,Actions} when AllowStateChange ->
+ {NextState,NewData,Actions,true};
+ %%
{keep_state,NewData} ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, State, []);
+ {State,NewData,[],false};
{keep_state,NewData,Actions} ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, State, Actions);
+ {State,NewData,Actions,false};
keep_state_and_data ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, Data, P, Event, State, []);
+ {State,Data,[],false};
{keep_state_and_data,Actions} ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, Data, P, Event, State, Actions);
+ {State,Data,Actions,false};
+ %%
+ {repeat_state,NewData} ->
+ {State,NewData,[],true};
+ {repeat_state,NewData,Actions} ->
+ {State,NewData,Actions,true};
+ repeat_state_and_data ->
+ {State,Data,[],true};
+ {repeat_state_and_data,Actions} ->
+ {State,Data,Actions,true};
+ %%
_ ->
terminate(
- error, {bad_return_value,Result}, ?STACKTRACE(),
- Debug, S, [Event|Events], State, Data, P)
+ error,
+ {bad_return_from_state_function,Result},
+ ?STACKTRACE(), Debug,
+ S#{state := State, data := Data},
+ [Event|Events])
end.
-loop_event_actions(
- Parent, Debug, S, Events, State, NewData, P, Event, NextState, Actions) ->
- Postpone = false, % Shall we postpone this event; boolean()
+
+parse_enter_actions(Debug, S, State, Actions, Hibernate, TimeoutsR) ->
+ Postpone = forbidden,
+ NextEventsR = forbidden,
+ parse_actions(
+ Debug, S, State, listify(Actions),
+ Hibernate, TimeoutsR, Postpone, NextEventsR).
+
+parse_actions(Debug, S, State, Actions) ->
Hibernate = false,
- Timeout = undefined,
- NextEvents = [],
- loop_event_actions(
- Parent, Debug, S, Events, State, NewData, P, Event, NextState,
- if
- is_list(Actions) ->
- Actions;
- true ->
- [Actions]
- end,
- Postpone, Hibernate, Timeout, NextEvents).
+ TimeoutsR = [infinity], %% Will cancel event timer
+ Postpone = false,
+ NextEventsR = [],
+ parse_actions(
+ Debug, S, State, listify(Actions),
+ Hibernate, TimeoutsR, Postpone, NextEventsR).
%%
-%% Process all actions
-loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, [Action|Actions],
- Postpone, Hibernate, Timeout, NextEvents) ->
+parse_actions(
+ Debug, _S, _State, [],
+ Hibernate, TimeoutsR, Postpone, NextEventsR) ->
+ {ok,Debug,Hibernate,TimeoutsR,Postpone,NextEventsR};
+parse_actions(
+ Debug, S, State, [Action|Actions],
+ Hibernate, TimeoutsR, Postpone, NextEventsR) ->
case Action of
%% Actual actions
{reply,From,Reply} ->
case from(From) of
true ->
NewDebug = do_reply(Debug, S, State, From, Reply),
- loop_event_actions(
- Parent, NewDebug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- Postpone, Hibernate, Timeout, NextEvents);
+ parse_actions(
+ NewDebug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR);
false ->
- terminate(
- error, {bad_action,Action}, ?STACKTRACE(),
- Debug, S, [Event|Events], State, NewData, P)
+ {error,
+ {bad_action_from_state_function,Action},
+ ?STACKTRACE()}
end;
+ %%
+ %% Actions that set options
+ {hibernate,NewHibernate} when is_boolean(NewHibernate) ->
+ parse_actions(
+ Debug, S, State, Actions,
+ NewHibernate, TimeoutsR, Postpone, NextEventsR);
+ hibernate ->
+ NewHibernate = true,
+ parse_actions(
+ Debug, S, State, Actions,
+ NewHibernate, TimeoutsR, Postpone, NextEventsR);
+ %%
+ {postpone,NewPostpone}
+ when is_boolean(NewPostpone), Postpone =/= forbidden ->
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, NewPostpone, NextEventsR);
+ postpone when Postpone =/= forbidden ->
+ NewPostpone = true,
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, NewPostpone, NextEventsR);
+ %%
{next_event,Type,Content} ->
case event_type(Type) of
+ true when NextEventsR =/= forbidden ->
+ NewDebug =
+ sys_debug(Debug, S, State, {in,{Type,Content}}),
+ parse_actions(
+ NewDebug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone,
+ [{Type,Content}|NextEventsR]);
+ _ ->
+ {error,
+ {bad_action_from_state_function,Action},
+ ?STACKTRACE()}
+ end;
+ %%
+ {{timeout,_},_,_} = Timeout ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
+ {{timeout,_},_,_,_} = Timeout ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
+ {timeout,_,_} = Timeout ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
+ {timeout,_,_,_} = Timeout ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
+ {state_timeout,_,_} = Timeout ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
+ {state_timeout,_,_,_} = Timeout ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
+ Time ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Time)
+ end.
+
+parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout) ->
+ case Timeout of
+ {TimerType,Time,TimerMsg,TimerOpts} ->
+ case validate_timer_args(Time, listify(TimerOpts)) of
true ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- Postpone, Hibernate, Timeout,
- [{Type,Content}|NextEvents]);
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, [Timeout|TimeoutsR],
+ Postpone, NextEventsR);
false ->
- terminate(
- error, {bad_action,Action}, ?STACKTRACE(),
- Debug, S, [Event|Events], State, NewData, P)
+ NewTimeout = {TimerType,Time,TimerMsg},
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, [NewTimeout|TimeoutsR],
+ Postpone, NextEventsR);
+ error ->
+ {error,
+ {bad_action_from_state_function,Timeout},
+ ?STACKTRACE()}
end;
- %% Actions that set options
- {postpone,NewPostpone} when is_boolean(NewPostpone) ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- NewPostpone, Hibernate, Timeout, NextEvents);
- {postpone,_} ->
- terminate(
- error, {bad_action,Action}, ?STACKTRACE(),
- Debug, S, [Event|Events], State, NewData, P);
- postpone ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- true, Hibernate, Timeout, NextEvents);
- {hibernate,NewHibernate} when is_boolean(NewHibernate) ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- Postpone, NewHibernate, Timeout, NextEvents);
- {hibernate,_} ->
- terminate(
- error, {bad_action,Action}, ?STACKTRACE(),
- Debug, S, [Event|Events], State, NewData, P);
- hibernate ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- Postpone, true, Timeout, NextEvents);
- {timeout,infinity,_} -> % Clear timer - it will never trigger
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- Postpone, Hibernate, undefined, NextEvents);
- {timeout,Time,_} = NewTimeout when is_integer(Time), Time >= 0 ->
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- Postpone, Hibernate, NewTimeout, NextEvents);
- {timeout,_,_} ->
- terminate(
- error, {bad_action,Action}, ?STACKTRACE(),
- Debug, S, [Event|Events], State, NewData, P);
- infinity -> % Clear timer - it will never trigger
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- Postpone, Hibernate, undefined, NextEvents);
- Time when is_integer(Time), Time >= 0 ->
- NewTimeout = {timeout,Time,Time},
- loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P, Event, NextState, Actions,
- Postpone, Hibernate, NewTimeout, NextEvents);
- _ ->
- terminate(
- error, {bad_action,Action}, ?STACKTRACE(),
- Debug, S, [Event|Events], State, NewData, P)
- end;
+ {_,Time,_} ->
+ case validate_timer_args(Time, []) of
+ false ->
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, [Timeout|TimeoutsR],
+ Postpone, NextEventsR);
+ error ->
+ {error,
+ {bad_action_from_state_function,Timeout},
+ ?STACKTRACE()}
+ end;
+ Time ->
+ case validate_timer_args(Time, []) of
+ false ->
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, [Timeout|TimeoutsR],
+ Postpone, NextEventsR);
+ error ->
+ {error,
+ {bad_action_from_state_function,Timeout},
+ ?STACKTRACE()}
+ end
+ end.
+
+validate_timer_args(Time, Opts) ->
+ validate_timer_args(Time, Opts, false).
%%
-%% End of actions list
-loop_event_actions(
- Parent, Debug, S, Events,
- State, NewData, P0, Event, NextState, [],
- Postpone, Hibernate, Timeout, NextEvents) ->
- %%
- %% All options have been collected and next_events are buffered.
- %% Do the actual state transition.
- %%
- P1 = % Move current event to postponed if Postpone
- case Postpone of
- true ->
- [Event|P0];
- false ->
- P0
- end,
- {Q2,P} = % Move all postponed events to queue if state change
- if
- NextState =:= State ->
- {Events,P1};
- true ->
- {lists:reverse(P1, Events),[]}
- end,
- %% Place next events first in queue
- Q = lists:reverse(NextEvents, Q2),
- %%
- NewDebug =
- sys_debug(
- Debug, S, State,
- case Postpone of
- true ->
- {postpone,Event,NextState};
- false ->
- {consume,Event,NextState}
- end),
- loop_events(
- Parent, NewDebug, S, Q, NextState, NewData, P, Hibernate, Timeout).
+validate_timer_args(Time, [], true) when is_integer(Time) ->
+ true;
+validate_timer_args(Time, [], false) when is_integer(Time), Time >= 0 ->
+ false;
+validate_timer_args(infinity, [], Abs) ->
+ Abs;
+validate_timer_args(Time, [{abs,Abs}|Opts], _) when is_boolean(Abs) ->
+ validate_timer_args(Time, Opts, Abs);
+validate_timer_args(_, [_|_], _) ->
+ error.
+
+%% Stop and start timers as well as create timeout zero events
+%% and pending event timer
+%%
+%% Stop and start timers non-event timers
+parse_timers(TimerRefs, TimerTypes, CancelTimers, TimeoutsR) ->
+ parse_timers(TimerRefs, TimerTypes, CancelTimers, TimeoutsR, #{}, []).
+%%
+parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, [], _Seen, TimeoutEvents) ->
+ {TimerRefs,TimerTypes,CancelTimers,TimeoutEvents};
+parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, [Timeout|TimeoutsR],
+ Seen, TimeoutEvents) ->
+ case Timeout of
+ {TimerType,Time,TimerMsg,TimerOpts} ->
+ %% Absolute timer
+ parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ TimerType, Time, TimerMsg, listify(TimerOpts));
+ %% Relative timers below
+ {TimerType,0,TimerMsg} ->
+ parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ TimerType, zero, TimerMsg, []);
+ {TimerType,Time,TimerMsg} ->
+ parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ TimerType, Time, TimerMsg, []);
+ 0 ->
+ parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ timeout, zero, 0, []);
+ Time ->
+ parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ timeout, Time, Time, [])
+ end.
+
+parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ TimerType, Time, TimerMsg, TimerOpts) ->
+ case Seen of
+ #{TimerType := _} ->
+ %% Type seen before - ignore
+ parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents);
+ #{} ->
+ %% Unseen type - handle
+ NewSeen = Seen#{TimerType => true},
+ case Time of
+ infinity ->
+ %% Cancel any running timer
+ {NewTimerTypes,NewCancelTimers} =
+ cancel_timer_by_type(
+ TimerType, TimerTypes, CancelTimers),
+ parse_timers(
+ TimerRefs, NewTimerTypes, NewCancelTimers, TimeoutsR,
+ NewSeen, TimeoutEvents);
+ zero ->
+ %% Cancel any running timer
+ {NewTimerTypes,NewCancelTimers} =
+ cancel_timer_by_type(
+ TimerType, TimerTypes, CancelTimers),
+ %% Handle zero time timeouts later
+ TimeoutEvent = {TimerType,TimerMsg},
+ parse_timers(
+ TimerRefs, NewTimerTypes, NewCancelTimers, TimeoutsR,
+ NewSeen, [TimeoutEvent|TimeoutEvents]);
+ _ ->
+ %% (Re)start the timer
+ TimerRef =
+ erlang:start_timer(
+ Time, self(), TimerMsg, TimerOpts),
+ case TimerTypes of
+ #{TimerType := OldTimerRef} ->
+ %% Cancel the running timer
+ cancel_timer(OldTimerRef),
+ NewCancelTimers = CancelTimers + 1,
+ %% Insert the new timer into
+ %% both TimerRefs and TimerTypes
+ parse_timers(
+ TimerRefs#{TimerRef => TimerType},
+ TimerTypes#{TimerType => TimerRef},
+ NewCancelTimers, TimeoutsR,
+ NewSeen, TimeoutEvents);
+ #{} ->
+ %% Insert the new timer into
+ %% both TimerRefs and TimerTypes
+ parse_timers(
+ TimerRefs#{TimerRef => TimerType},
+ TimerTypes#{TimerType => TimerRef},
+ CancelTimers, TimeoutsR,
+ NewSeen, TimeoutEvents)
+ end
+ end
+ end.
+
+%% Enqueue immediate timeout events (timeout 0 events)
+%%
+%% Event timer timeout 0 events gets special treatment since
+%% an event timer is cancelled by any received event,
+%% so if there are enqueued events before the event timer
+%% timeout 0 event - the event timer is cancelled hence no event.
+%%
+%% Other (state_timeout) timeout 0 events that are after
+%% the event timer timeout 0 events are considered to
+%% belong to timers that were started after the event timer
+%% timeout 0 event fired, so they do not cancel the event timer.
+%%
+prepend_timeout_events([], EventsR) ->
+ EventsR;
+prepend_timeout_events([{timeout,_} = TimeoutEvent|TimeoutEvents], []) ->
+ prepend_timeout_events(TimeoutEvents, [TimeoutEvent]);
+prepend_timeout_events([{timeout,_}|TimeoutEvents], EventsR) ->
+ prepend_timeout_events(TimeoutEvents, EventsR);
+prepend_timeout_events([TimeoutEvent|TimeoutEvents], EventsR) ->
+ %% Just prepend all others
+ prepend_timeout_events(TimeoutEvents, [TimeoutEvent|EventsR]).
+
+
%%---------------------------------------------------------------------------
%% Server helpers
reply_then_terminate(
- Class, Reason, Stacktrace,
- Debug, S, Q, State, Data, P, Replies) ->
- if
- is_list(Replies) ->
- do_reply_then_terminate(
- Class, Reason, Stacktrace,
- Debug, S, Q, State, Data, P, Replies);
- true ->
- do_reply_then_terminate(
- Class, Reason, Stacktrace,
- Debug, S, Q, State, Data, P, [Replies])
- end.
+ Class, Reason, Stacktrace, Debug,
+ #{state := State} = S, Q, Replies) ->
+ do_reply_then_terminate(
+ Class, Reason, Stacktrace, Debug,
+ S, Q, listify(Replies), State).
%%
do_reply_then_terminate(
- Class, Reason, Stacktrace, Debug, S, Q, State, Data, P, []) ->
- terminate(Class, Reason, Stacktrace, Debug, S, Q, State, Data, P);
+ Class, Reason, Stacktrace, Debug, S, Q, [], _State) ->
+ terminate(Class, Reason, Stacktrace, Debug, S, Q);
do_reply_then_terminate(
- Class, Reason, Stacktrace, Debug, S, Q, State, Data, P, [R|Rs]) ->
+ Class, Reason, Stacktrace, Debug, S, Q, [R|Rs], State) ->
case R of
{reply,{_To,_Tag}=From,Reply} ->
NewDebug = do_reply(Debug, S, State, From, Reply),
do_reply_then_terminate(
- Class, Reason, Stacktrace,
- NewDebug, S, Q, State, Data, P, Rs);
+ Class, Reason, Stacktrace, NewDebug, S, Q, Rs, State);
_ ->
terminate(
- error, {bad_action,R}, ?STACKTRACE(),
- Debug, S, Q, State, Data, P)
+ error,
+ {bad_reply_action_from_state_function,R},
+ ?STACKTRACE(),
+ Debug, S, Q)
end.
do_reply(Debug, S, State, From, Reply) ->
@@ -1179,28 +1650,40 @@ do_reply(Debug, S, State, From, Reply) ->
terminate(
- Class, Reason, Stacktrace,
- Debug, #{module := Module} = S, Q, State, Data, P) ->
- try Module:terminate(Reason, State, Data) of
- _ -> ok
- catch
- _ -> ok;
- C:R ->
- ST = erlang:get_stacktrace(),
- error_info(
- C, R, ST, Debug, S, Q, P,
- format_status(terminate, get(), S, State, Data)),
- erlang:raise(C, R, ST)
- end,
- case Reason of
- normal -> ok;
- shutdown -> ok;
- {shutdown,_} -> ok;
- _ ->
- error_info(
- Class, Reason, Stacktrace, Debug, S, Q, P,
- format_status(terminate, get(), S, State, Data))
+ Class, Reason, Stacktrace, Debug,
+ #{module := Module, state := State, data := Data, postponed := P} = S,
+ Q) ->
+ case erlang:function_exported(Module, terminate, 3) of
+ true ->
+ try Module:terminate(Reason, State, Data) of
+ _ -> ok
+ catch
+ _ -> ok;
+ C:R ->
+ ST = erlang:get_stacktrace(),
+ error_info(
+ C, R, ST, S, Q, P,
+ format_status(terminate, get(), S)),
+ sys:print_log(Debug),
+ erlang:raise(C, R, ST)
+ end;
+ false ->
+ ok
end,
+ _ =
+ case Reason of
+ normal ->
+ sys_debug(Debug, S, State, {terminate,Reason});
+ shutdown ->
+ sys_debug(Debug, S, State, {terminate,Reason});
+ {shutdown,_} ->
+ sys_debug(Debug, S, State, {terminate,Reason});
+ _ ->
+ error_info(
+ Class, Reason, Stacktrace, S, Q, P,
+ format_status(terminate, get(), S)),
+ sys:print_log(Debug)
+ end,
case Stacktrace of
[] ->
erlang:Class(Reason);
@@ -1209,8 +1692,10 @@ terminate(
end.
error_info(
- Class, Reason, Stacktrace, Debug,
- #{name := Name, callback_mode := CallbackMode},
+ Class, Reason, Stacktrace,
+ #{name := Name,
+ callback_mode := CallbackMode,
+ state_enter := StateEnter},
Q, P, FmtData) ->
{FixedReason,FixedStacktrace} =
case Stacktrace of
@@ -1237,6 +1722,15 @@ error_info(
end;
_ -> {Reason,Stacktrace}
end,
+ [LimitedP, LimitedFmtData, LimitedFixedReason] =
+ [error_logger:limit_term(D) || D <- [P, FmtData, FixedReason]],
+ CBMode =
+ case StateEnter of
+ true ->
+ [CallbackMode,state_enter];
+ false ->
+ CallbackMode
+ end,
error_logger:format(
"** State machine ~p terminating~n" ++
case Q of
@@ -1263,26 +1757,27 @@ error_info(
[] -> [];
[Event|_] -> [Event]
end] ++
- [FmtData,Class,FixedReason,
- CallbackMode] ++
+ [LimitedFmtData,
+ Class,LimitedFixedReason,
+ CBMode] ++
case Q of
[_|[_|_] = Events] -> [Events];
_ -> []
end ++
case P of
[] -> [];
- _ -> [P]
+ _ -> [LimitedP]
end ++
case FixedStacktrace of
[] -> [];
_ -> [FixedStacktrace]
- end),
- sys:print_log(Debug),
- ok.
+ end).
%% Call Module:format_status/2 or return a default value
-format_status(Opt, PDict, #{module := Module}, State, Data) ->
+format_status(
+ Opt, PDict,
+ #{module := Module, state := State, data := Data}) ->
case erlang:function_exported(Module, format_status, 2) of
true ->
try Module:format_status(Opt, [PDict,State,Data])
@@ -1291,7 +1786,7 @@ format_status(Opt, PDict, #{module := Module}, State, Data) ->
_:_ ->
format_status_default(
Opt, State,
- "Module:format_status/2 crashed")
+ atom_to_list(Module) ++ ":format_status/2 crashed")
end;
false ->
format_status_default(Opt, State, Data)
@@ -1299,10 +1794,35 @@ format_status(Opt, PDict, #{module := Module}, State, Data) ->
%% The default Module:format_status/2
format_status_default(Opt, State, Data) ->
- SSD = {State,Data},
+ StateData = {State,Data},
case Opt of
terminate ->
- SSD;
+ StateData;
_ ->
- [{data,[{"State",SSD}]}]
+ [{data,[{"State",StateData}]}]
+ end.
+
+listify(Item) when is_list(Item) ->
+ Item;
+listify(Item) ->
+ [Item].
+
+%% Cancel timer if running, otherwise no op
+%%
+%% This is an asynchronous cancel so the timer is not really cancelled
+%% until we get a cancel_timer msg i.e {cancel_timer,TimerRef,_}.
+%% In the mean time we might get a timeout message.
+%%
+%% Remove the timer from TimerTypes.
+%% When we get the cancel_timer msg we remove it from TimerRefs.
+cancel_timer_by_type(TimerType, TimerTypes, CancelTimers) ->
+ case TimerTypes of
+ #{TimerType := TimerRef} ->
+ cancel_timer(TimerRef),
+ {maps:remove(TimerType, TimerTypes),CancelTimers + 1};
+ #{} ->
+ {TimerTypes,CancelTimers}
end.
+
+cancel_timer(TimerRef) ->
+ ok = erlang:cancel_timer(TimerRef, [{async,true}]).