diff options
Diffstat (limited to 'lib/stdlib/src/gen_statem.erl')
| -rw-r--r-- | lib/stdlib/src/gen_statem.erl | 2616 |
1 files changed, 1645 insertions, 971 deletions
diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl index cacc932ec4..49911eac2c 100644 --- a/lib/stdlib/src/gen_statem.erl +++ b/lib/stdlib/src/gen_statem.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 2016-2017. All Rights Reserved. +%% Copyright Ericsson AB 2016-2019. 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. @@ -19,6 +19,8 @@ %% -module(gen_statem). +-include("logger.hrl"). + %% API -export( [start/3,start/4,start_link/3,start_link/4, @@ -44,6 +46,9 @@ -export( [wakeup_from_hibernate/3]). +%% logger callback +-export([format_log/1]). + %% Type exports for templates and callback modules -export_type( [event_type/0, @@ -62,6 +67,14 @@ %% 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. %%%========================================================================== @@ -78,8 +91,11 @@ -type data() :: term(). -type event_type() :: - {'call',From :: from()} | 'cast' | - 'info' | 'timeout' | 'state_timeout' | 'internal'. + 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()]. @@ -88,7 +104,7 @@ -type transition_option() :: postpone() | hibernate() | - event_timeout() | state_timeout(). + event_timeout() | generic_timeout() | state_timeout(). -type postpone() :: %% If 'true' postpone the current event %% and retry it when the state changes (=/=) @@ -97,13 +113,17 @@ %% 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 after Time + %% Generate a ('state_timeout', EventContent, ...) event %% unless the state is changed - Time :: timeout(). + Time :: timeout() | integer(). +-type timeout_option() :: {abs,Abs :: boolean()}. -type action() :: %% During a state change: @@ -133,14 +153,30 @@ -type enter_action() :: 'hibernate' | % Set the hibernate option {'hibernate', Hibernate :: hibernate()} | - %% - (Timeout :: event_timeout()) | % {timeout,Timeout} + 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()} | - %% - reply_action(). + {'state_timeout', % Set the state_timeout option + Time :: state_timeout(), + EventContent :: term(), + Options :: (timeout_option() | [timeout_option()])}. -type reply_action() :: {'reply', % Reply to a caller From :: from(), Reply :: term()}. @@ -275,7 +311,7 @@ (Reason :: term()). %% Format the callback module state in some sensible that is -%% often condensed way. For StatusOption =:= 'normal' the perferred +%% 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( @@ -287,8 +323,7 @@ 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 %% @@ -300,71 +335,123 @@ handle_event/4 % 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 + state_functions -> true; + handle_event_function -> true; + _ -> false end. %% -from({Pid,_}) when is_pid(Pid) -> - true; -from(_) -> - false. +state_enter(StateEnter) -> + case StateEnter of + state_enter -> + true; + _ -> + false + end. %% -event_type({call,From}) -> - from(From); event_type(Type) -> case Type of - {call,From} -> - from(From); - cast -> - true; - info -> - true; - timeout -> - true; - state_timeout -> - true; - internal -> - true; - _ -> - false + {call,From} -> from(From); + %% + cast -> true; + info -> true; + internal -> true; + _ -> timeout_event_type(Type) + end. +%% +from({Pid,_}) when is_pid(Pid) -> true; +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(), - try throw(ok) catch _ -> erlang:get_stacktrace() end). + 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(), + module :: atom(), + name :: atom() | pid(), + hibernate_after = infinity :: timeout() + }). + +-record(state, + {state_data = {undefined,undefined} :: + {State :: term(),Data :: term()}, + postponed = [] :: [{event_type(),term()}], + timers = {#{},#{}} :: + {%% TimerRef => TimeoutType + TimerRefs :: #{reference() => timeout_event_type()}, + %% TimeoutType => TimerRef + TimeoutTypes :: #{timeout_event_type() => reference()}}, + hibernate = false :: boolean() + }). %%%========================================================================== %%% API -type server_name() :: - {'global', GlobalName :: term()} + {'global', GlobalName :: term()} | {'via', RegMod :: module(), Name :: term()} | {'local', atom()}. -type server_ref() :: - pid() + pid() | (LocalName :: atom()) | {Name :: atom(), Node :: atom()} | {'global', GlobalName :: term()} | {'via', RegMod :: module(), ViaName :: term()}. --type debug_opt() :: - {'debug', - Dbgs :: - ['trace' | 'log' | 'statistics' | 'debug' - | {'logfile', string()}]}. -type start_opt() :: - debug_opt() - | {'timeout', Time :: timeout()} - | {'spawn_opt', [proc_lib:spawn_option()]}. --type start_ret() :: {'ok', pid()} | 'ignore' | {'error', term()}. + {'timeout', Time :: timeout()} + | {'spawn_opt', [proc_lib:spawn_option()]} + | enter_loop_opt(). +-type start_ret() :: + {'ok', pid()} + | 'ignore' + | {'error', term()}. +-type enter_loop_opt() :: + {'hibernate_after', HibernateAfterTimeout :: timeout()} + | {'debug', Dbgs :: [sys:debug_option()]}. @@ -410,6 +497,10 @@ 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 @@ -423,10 +514,6 @@ cast({via,RegMod,Name}, Msg) -> _:_ -> ok end; cast({Name,Node} = ServerRef, Msg) when is_atom(Name), is_atom(Node) -> - send(ServerRef, wrap_cast(Msg)); -cast(ServerRef, Msg) when is_atom(ServerRef) -> - send(ServerRef, wrap_cast(Msg)); -cast(ServerRef, Msg) when is_pid(ServerRef) -> send(ServerRef, wrap_cast(Msg)). %% Call a state machine (synchronous; a reply is expected) that @@ -443,75 +530,16 @@ call(ServerRef, Request) -> {'clean_timeout',T :: timeout()} | {'dirty_timeout',T :: timeout()}) -> 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]); call(ServerRef, Request, Timeout) -> - 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; - 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. + call_clean(ServerRef, Request, Timeout, Timeout). %% Reply from a state machine callback to whom awaits in call/2 -spec reply([reply_action()] | reply_action()) -> ok. @@ -520,6 +548,7 @@ reply({reply,From,Reply}) -> reply(Replies) when is_list(Replies) -> replies(Replies). %% +-compile({inline, [reply/2]}). -spec reply(From :: from(), Reply :: term()) -> ok. reply({To,Tag}, Reply) when is_pid(To) -> Msg = {Tag,Reply}, @@ -535,14 +564,14 @@ 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()], + 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 :: [debug_opt()], + Module :: module(), Opts :: [enter_loop_opt()], State :: state(), Data :: data(), Server_or_Actions :: server_name() | pid() | [action()]) -> @@ -556,7 +585,7 @@ enter_loop(Module, Opts, State, Data, Server_or_Actions) -> end. %% -spec enter_loop( - Module :: module(), Opts :: [debug_opt()], + Module :: module(), Opts :: [enter_loop_opt()], State :: state(), Data :: data(), Server :: server_name() | pid(), Actions :: [action()] | action()) -> @@ -564,14 +593,68 @@ enter_loop(Module, Opts, State, Data, Server_or_Actions) -> enter_loop(Module, Opts, State, Data, Server, Actions) -> is_atom(Module) orelse error({atom,Module}), Parent = gen:get_parent(), - enter(Module, Opts, State, Data, Server, Actions, Parent). + Name = gen:get_proc_name(Server), + Debug = gen:debug_options(Name, Opts), + HibernateAfterTimeout = gen:hibernate_after(Opts), + enter( + Parent, Debug, Module, Name, HibernateAfterTimeout, + State, Data, Actions). %%--------------------------------------------------------------------------- %% API helpers +-compile({inline, [wrap_cast/1]}). wrap_cast(Event) -> {'$gen_cast',Event}. +call_dirty(ServerRef, Request, Timeout, T) -> + try gen:call(ServerRef, '$gen_call', Request, T) of + {ok,Reply} -> + Reply + catch + Class:Reason:Stacktrace -> + erlang:raise( + Class, + {Reason,{?MODULE,call,[ServerRef,Request,Timeout]}}, + Stacktrace) + end. + +call_clean(ServerRef, Request, 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:Stacktrace -> + {Ref,Class,Reason,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. + replies([{reply,From,Reply}|Replies]) -> reply(From, Reply), replies(Replies); @@ -580,78 +663,36 @@ replies([]) -> %% Might actually not send the message in case of caught exception send(Proc, Msg) -> - try erlang:send(Proc, Msg, [noconnect]) of - noconnect -> - _ = spawn(erlang, send, [Proc,Msg]), - ok; - ok -> - ok + try erlang:send(Proc, Msg) catch - _:_ -> - ok - end. + error:_ -> ok + end, + ok. %% Here the init_it/6 and enter_loop/5,6,7 functions converge -enter(Module, Opts, State, Data, Server, Actions, Parent) -> +enter( + Parent, Debug, Module, Name, HibernateAfterTimeout, + State, Data, Actions) -> %% The values should already have been type checked - Name = gen:get_proc_name(Server), - Debug = gen:debug_options(Name, Opts), - Events = [], - P = [], - Event = {internal,init_state}, + Q = [{internal,init_state}], %% We enforce {postpone,false} to ensure that %% our fake Event gets discarded, thought it might get logged - NewActions = - if - is_list(Actions) -> - Actions ++ [{postpone,false}]; - 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 => undefined, - state_enter => false, - module => Module, - name => Name, - state => State, - data => Data, - postponed => P, - %% - %% 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, - cancel_timers => CancelTimers - }, - NewDebug = sys_debug(Debug, S, State, {enter,Event,State}), - 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. + Actions_1 = listify(Actions) ++ [{postpone,false}], + P = + #params{ + parent = Parent, + module = Module, + name = Name, + hibernate_after = HibernateAfterTimeout}, + S = #state{state_data = {State,Data}}, + Debug_1 = ?sys_debug(Debug, Name, {enter,State}), + loop_callback_mode( + 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 @@ -659,37 +700,46 @@ enter(Module, Opts, State, Data, Server, Actions, Parent) -> 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 = gen:get_proc_name(ServerRef), + Debug = gen:debug_options(Name, Opts), + HibernateAfterTimeout = gen:hibernate_after(Opts), try Module:init(Args) of Result -> - init_result(Starter, Parent, ServerRef, Module, Result, Opts) + init_result( + Starter, Parent, ServerRef, Module, Result, + Name, Debug, HibernateAfterTimeout) catch Result -> - init_result(Starter, Parent, ServerRef, Module, Result, Opts); - Class:Reason -> - Stacktrace = erlang:get_stacktrace(), - Name = gen:get_proc_name(ServerRef), + init_result( + Starter, Parent, ServerRef, Module, Result, + Name, Debug, HibernateAfterTimeout); + Class:Reason:Stacktrace -> gen:unregister_name(ServerRef), proc_lib:init_ack(Starter, {error,Reason}), error_info( - Class, Reason, Stacktrace, - #{name => Name, - callback_mode => undefined, - state_enter => false}, - [], [], undefined), + Class, Reason, Stacktrace, Debug, + #params{parent = Parent, name = Name, module = Module}, + #state{}, []), erlang:raise(Class, Reason, Stacktrace) end. %%--------------------------------------------------------------------------- %% gen callbacks helpers -init_result(Starter, Parent, ServerRef, Module, Result, Opts) -> +init_result( + Starter, Parent, ServerRef, Module, Result, + Name, Debug, HibernateAfterTimeout) -> case Result of {ok,State,Data} -> proc_lib:init_ack(Starter, {ok,self()}), - enter(Module, Opts, State, Data, ServerRef, [], Parent); + enter( + Parent, Debug, Module, Name, HibernateAfterTimeout, + State, Data, []); {ok,State,Data,Actions} -> proc_lib:init_ack(Starter, {ok,self()}), - enter(Module, Opts, State, Data, ServerRef, Actions, Parent); + enter( + Parent, Debug, Module, Name, HibernateAfterTimeout, + State, Data, Actions); {stop,Reason} -> gen:unregister_name(ServerRef), proc_lib:init_ack(Starter, {error,Reason}), @@ -699,32 +749,34 @@ init_result(Starter, Parent, ServerRef, Module, Result, Opts) -> proc_lib:init_ack(Starter, ignore), exit(normal); _ -> - 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), + error, Error, ?STACKTRACE(), Debug, + #params{parent = Parent, name = Name, module = 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, S) -> - loop(Parent, Debug, S). +system_continue(Parent, Debug, {P,S}) -> + loop(update_parent(P, Parent), Debug, S). -system_terminate(Reason, _Parent, Debug, S) -> - terminate(exit, Reason, ?STACKTRACE(), Debug, S, []). +system_terminate(Reason, Parent, Debug, {P,S}) -> + terminate( + exit, Reason, ?STACKTRACE(), + update_parent(P, Parent), Debug, S, []). system_code_change( - #{module := Module, - state := State, - data := Data} = S, + {#params{module = Module} = P, + #state{state_data = {State,Data}} = S}, _Mod, OldVsn, Extra) -> case try Module:code_change(OldVsn, State, Data, Extra) @@ -734,255 +786,228 @@ system_code_change( of {ok,NewState,NewData} -> {ok, - S#{callback_mode := undefined, - state := NewState, - data := NewData}}; + {P#params{callback_mode = undefined}, + S#state{state_data = {NewState,NewData}}}}; {ok,_} = Error -> error({case_clause,Error}); Error -> Error end. -system_get_state(#{state := State, data := Data}) -> - {ok,{State,Data}}. +system_get_state({_P,#state{state_data = State_Data}}) -> + {ok,State_Data}. system_replace_state( - StateFun, - #{state := State, - data := Data} = S) -> - {NewState,NewData} = Result = StateFun({State,Data}), - {ok,Result,S#{state := NewState, data := NewData}}. + 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, - #{name := Name, postponed := P} = S]) -> + {#params{name = Name} = P, + #state{postponed = Postponed} = S}]) -> Header = gen:format_status_header("Status for state machine", Name), - Log = sys:get_debug(log, Debug, []), + Log = sys:get_log(Debug), [{header,Header}, {data, [{"Status",SysState}, {"Parent",Parent}, {"Logged Events",Log}, - {"Postponed",P}]} | - case format_status(Opt, PDict, S) of + {"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. %%--------------------------------------------------------------------------- -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 send ~p to ~p from state ~p~n", - [Name,Reply,To,State]); -print_event(Dev, {terminate,Reason}, {Name,State}) -> - io:format( - Dev, "*DBG* ~p terminate ~p in state ~p~n", - [Name,Reason,State]); -print_event(Dev, {Tag,Event,NextState}, {Name,State}) -> - StateString = - case NextState of - State -> - io_lib:format("~p", [State]); - _ -> - io_lib:format("~p => ~p", [State,NextState]) - end, - io:format( - Dev, "*DBG* ~p ~w ~s in state ~s~n", - [Name,Tag,event_string(Event),StateString]). +sys_debug(Debug, NameState, Entry) -> + 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]); + {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 ~p from ~w", [Request,Pid]); + io_lib:format("call ~tp from ~tw", [Request,Pid]); {EventType,EventContent} -> - io_lib:format("~w ~p", [EventType,EventContent]) - end. - -sys_debug(Debug, #{name := Name}, State, Entry) -> - case Debug of - [] -> - Debug; - _ -> - sys:handle_debug( - Debug, fun print_event/3, {Name,State}, Entry) + io_lib:format("~tw ~tp", [EventType,EventContent]) end. %%%========================================================================== %%% Internal callbacks -wakeup_from_hibernate(Parent, Debug, S) -> +wakeup_from_hibernate(P, Debug, S) -> %% It is a new message that woke us up so we have to receive it now - loop_receive(Parent, Debug, S). + loop_receive(P, Debug, S). %%%========================================================================== -%%% State Machine engine implementation of proc_lib/gen server +%%% State Machine engine implementation on proc_lib/gen %% Server loop, consists of all loop* functions %% and detours through sys:handle_system_message/7 and 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(Parent, Debug, #{hibernate := true, cancel_timers := 0} = S) -> - loop_hibernate(Parent, Debug, S); -loop(Parent, Debug, S) -> - loop_receive(Parent, Debug, S). +%% +loop(P, Debug, #state{hibernate = true} = S) -> + loop_hibernate(P, Debug, S); +loop(P, Debug, S) -> + loop_receive(P, Debug, S). -loop_hibernate(Parent, 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 - proc_lib:hibernate( - ?MODULE, wakeup_from_hibernate, [Parent,Debug,S]), + %% + proc_lib:hibernate(?MODULE, wakeup_from_hibernate, [P, Debug, S]), error( {should_not_have_arrived_here_but_instead_in, - {wakeup_from_hibernate,3}}). + {?MODULE,wakeup_from_hibernate,3}}). + %% Entry point for wakeup_from_hibernate/3 -loop_receive(Parent, Debug, S) -> +%% +%% 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,TimeoutMsg} -> + {TimerRefs,TimeoutTypes} = S#state.timers, + case TimerRefs of + #{TimerRef := TimeoutType} -> + %% Our timer + Timers = + {maps:remove(TimerRef, TimerRefs), + maps:remove(TimeoutType, TimeoutTypes)}, + S_1 = S#state{timers = Timers}, + loop_receive_result( + P, Debug, S_1, {TimeoutType,TimeoutMsg}); + #{} -> + loop_receive_result(P, Debug, S, {info,Msg}) + end; + %% {system,Pid,Req} -> - #{hibernate := Hibernate} = 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); - {'EXIT',Parent,Reason} = EXIT -> - %% 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; - _ -> - %% 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} -> - {{call,From},Request}; - {'$gen_cast',E} -> - {cast,E}; - _ -> - {info,Msg} - end, - loop_receive_result( - Parent, Debug, S, Hibernate, Event) + 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( - Parent, Debug, - #{state := State, - 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}), + #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 = [], - %% 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_event(P, Debug_1, S, Event, Events). -%% Entry point for handling an event, received or enqueued +%% Handle one event; received or enqueued +%% loop_event( - Parent, Debug, - #{state := State, data := Data} = S, - Events, {Type,Content} = Event, Hibernate) -> + 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 @@ -990,233 +1015,130 @@ loop_event( %% 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. + %% 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). -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) -> +%% Call the state function, eventually +%% +-compile({inline, [loop_event_handler/5]}). +loop_event_handler( + P, Debug, #state{state_data = State_Data} = S, Event, Events) -> %% - %% All options have been collected and next_events are buffered. - %% Do the actual state transition. + %% The field 'hibernate' in S is now invalid and will be + %% restored when looping back to loop/3 or loop_event/5. %% - {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. + Q = [Event|Events], + loop_callback_mode(P, Debug, S, Q, State_Data, Event). - -%%--------------------------------------------------------------------------- -%% Server loop helpers - -call_callback_mode(#{module := Module} = S) -> +%% Figure out the callback mode +%% +loop_callback_mode( + #params{callback_mode = undefined} = P, Debug, S, + Q, State_Data, CallbackEvent) -> + %% + Module = P#params.module, try Module:callback_mode() of CallbackMode -> - callback_mode_result(S, CallbackMode) + loop_callback_mode_result( + P, Debug, S, + Q, State_Data, CallbackEvent, + CallbackMode, listify(CallbackMode), undefined, false) 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. + loop_callback_mode_result( + P, Debug, S, + Q, State_Data, CallbackEvent, + CallbackMode, listify(CallbackMode), undefined, false); + Class:Reason:Stacktrace -> + terminate( + Class, Reason, Stacktrace, P, Debug, S, Q) + end; +loop_callback_mode(P, Debug, S, Q, State_Data, CallbackEvent) -> + loop_state_callback(P, Debug, S, Q, State_Data, CallbackEvent). -parse_callback_mode([], CBMode, StateEnter) -> - {CBMode,StateEnter}; -parse_callback_mode([H|T], CBMode, StateEnter) -> +%% Check the result of Module:callback_mode() +%% +loop_callback_mode_result( + P, Debug, S, Q, State_Data, CallbackEvent, + CallbackMode, [H|T], NewCallbackMode, NewStateEnter) -> + %% 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 + true -> + loop_callback_mode_result( + P, Debug, S, Q, State_Data, CallbackEvent, + CallbackMode, T, H, NewStateEnter); + false -> + case state_enter(H) of + true -> + loop_callback_mode_result( + P, Debug, S, Q, State_Data, CallbackEvent, + CallbackMode, T, NewCallbackMode, true); + false -> + terminate( + error, + {bad_return_from_callback_mode,CallbackMode}, + ?STACKTRACE(), + P, Debug, S, Q) + end end; -parse_callback_mode(_, _CBMode, StateEnter) -> - {undefined,StateEnter}. +loop_callback_mode_result( + P, Debug, S, Q, State_Data, 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, CallbackEvent) + end. -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) -> +%% 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 = CallbackMode, module = Module} = P, + Debug, S, Q, {State,Data} = State_Data, + NextEventsR, Hibernate, TimeoutsR, Postpone, + StateCall, {Type,Content}) -> try case CallbackMode of state_functions -> @@ -1226,279 +1148,910 @@ call_state_function( end of Result -> - {ok,Result,S} + loop_state_callback_result( + P, Debug, S, Q, State_Data, + NextEventsR, Hibernate, TimeoutsR, Postpone, + StateCall, Result) catch Result -> - {ok,Result,S}; - Class:Reason -> - {Class,Reason,erlang:get_stacktrace()} - end. - - -%% Interpret all callback return variants -parse_event_result( - AllowStateChange, Debug, S, - Events, Event, State, Data, 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). + +%% 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(), Debug, - S#{state := State, data := Data}, - [Event|Events]); + terminate( + exit, normal, ?STACKTRACE(), P, Debug, + S#state{ + state_data = State_Data, + hibernate = Hibernate}, + Q); {stop,Reason} -> - terminate( - exit, Reason, ?STACKTRACE(), Debug, - S#{state := State, data := Data}, - [Event|Events]); + terminate( + exit, Reason, ?STACKTRACE(), P, Debug, + S#state{ + state_data = State_Data, + hibernate = Hibernate}, + Q); {stop,Reason,NewData} -> - terminate( - exit, Reason, ?STACKTRACE(), Debug, - S#{state := State, data := NewData}, - [Event|Events]); + 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(), Debug, - S#{state := State, data := Data}, - [Event|Events], 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(), 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} -> - {State,NewData,[],false}; - {keep_state,NewData,Actions} -> - {State,NewData,Actions,false}; - keep_state_and_data -> - {State,Data,[],false}; - {keep_state_and_data,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}; + 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(), Debug, - S#{state := State, data := Data}, - [Event|Events]) + 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. -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, - TimeoutsR = [{timeout,infinity,infinity}], %% Will cancel event timer - Postpone = false, - NextEventsR = [], - parse_actions( - Debug, S, State, listify(Actions), - Hibernate, TimeoutsR, Postpone, NextEventsR). -%% -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) -> +%% 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} -> - case from(From) of - true -> - NewDebug = do_reply(Debug, S, State, From, Reply), - parse_actions( - NewDebug, S, State, Actions, - Hibernate, TimeoutsR, Postpone, NextEventsR); - false -> - {error, - {bad_action_from_state_function,Action}, - ?STACKTRACE()} - end; + loop_actions_reply( + P, Debug, S, Q, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postpone, + CallEnter, StateCall, Actions, + From, Reply); %% %% Actions that set options - {hibernate,NewHibernate} when is_boolean(NewHibernate) -> - parse_actions( - Debug, S, State, Actions, - NewHibernate, TimeoutsR, Postpone, NextEventsR); + {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 -> - NewHibernate = true, - parse_actions( - Debug, S, State, Actions, - NewHibernate, TimeoutsR, Postpone, NextEventsR); + loop_actions_list( + P, Debug, S, Q, NextState_NewData, + NextEventsR, true, TimeoutsR, Postpone, + CallEnter, StateCall, Actions); %% - {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); + {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} -> - 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; + loop_actions_next_event( + P, Debug, S, Q, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postpone, + CallEnter, StateCall, Actions, Type, Content); %% - {state_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); - Time -> - parse_actions_timeout( - Debug, S, State, Actions, - Hibernate, TimeoutsR, Postpone, NextEventsR, Time) + Timeout -> + loop_actions_timeout( + P, Debug, S, Q, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postpone, + CallEnter, StateCall, Actions, Timeout) + 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. -parse_actions_timeout( - Debug, S, State, Actions, - Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout) -> - Time = - case Timeout of - {_,T,_} -> T; - T -> T +%% 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. + +%% Process a timeout action, or also any unrecognized action +%% +loop_actions_timeout( + 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 + [] 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); + [{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); + %% 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); + badarg -> + 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_timeout( + P, Debug, S, Q, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postpone, + CallEnter, StateCall, Actions, + {TimeoutType,Time,_} = Timeout) -> + %% + case timeout_event_type(TimeoutType) of + true when ?relative_timeout(Time) -> + 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_timeout( + P, Debug, S, Q, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postpone, + CallEnter, StateCall, Actions, Time) -> + %% + if + ?relative_timeout(Time) -> + RelativeTimeout = {timeout,Time,Time}, + loop_actions_list( + P, Debug, S, Q, NextState_NewData, + NextEventsR, Hibernate, + [RelativeTimeout|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. + +%% 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 validate_time(Time) of - true -> - parse_actions( - Debug, S, State, Actions, - Hibernate, [Timeout|TimeoutsR], - Postpone, NextEventsR); - false -> - {error, - {bad_action_from_state_function,Timeout}, - ?STACKTRACE()} + 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. -validate_time(Time) when is_integer(Time), Time >= 0 -> true; -validate_time(infinity) -> true; -validate_time(_) -> false. +%% State transition to the same state +%% +loop_keep_state( + P, Debug, #state{timers = {TimerRefs,TimeoutTypes} = Timers} = S, + Events, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postponed) -> + %% + %% Cancel event timeout + %% + case TimeoutTypes of + %% Optimization + %% - only cancel timer when there is a timer to cancel + #{timeout := TimerRef} -> + %% Event timeout active + loop_next_events( + P, Debug, S, + Events, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postponed, + cancel_timer_by_ref_and_type( + TimerRef, timeout, TimerRefs, TimeoutTypes)); + _ -> + %% 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 = {TimerRefs,TimeoutTypes} = Timers} = S, + Events, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR) -> + %% + %% Cancel state and event timeout + %% + case TimeoutTypes of + %% Optimization + %% - only cancel timeout when there is an active timeout + %% + #{state_timeout := TimerRef} -> + %% 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_by_type( + timeout, + cancel_timer_by_ref_and_type( + TimerRef, state_timeout, TimerRefs, TimeoutTypes))); + #{timeout := TimerRef} -> + %% 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_by_ref_and_type( + TimerRef, timeout, TimerRefs, TimeoutTypes)); + _ -> + %% No state nor event timeout active. + loop_next_events( + P, Debug, S, Events, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, [], + Timers) + end. -%% Stop and start timers as well as create timeout zero events -%% and pending event timer +%% Continue state transition with processing of +%% inserted events and timeout events %% -%% Stop and start timers non-event timers -parse_timers(TimerRefs, TimerTypes, CancelTimers, TimeoutsR) -> - parse_timers(TimerRefs, TimerTypes, CancelTimers, TimeoutsR, #{}, []). +loop_next_events( + P, Debug, S, + Events, NextState_NewData, + NextEventsR, Hibernate, [], Postponed, + Timers) -> + %% + %% Optimization when there are no timeout actions + %% hence no timeout zero events to append to Events + %% - avoid loop_timeouts + loop_done( + P, Debug, + S#state{ + state_data = NextState_NewData, + postponed = Postponed, + timers = Timers, + hibernate = Hibernate}, + NextEventsR, Events); +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 timeout events %% -parse_timers( - TimerRefs, TimerTypes, CancelTimers, [], _Seen, TimeoutEvents) -> - {TimerRefs,TimerTypes,CancelTimers,TimeoutEvents}; -parse_timers( - TimerRefs, TimerTypes, CancelTimers, [Timeout|TimeoutsR], - Seen, TimeoutEvents) -> +loop_timeouts( + P, Debug, S, + Events, NextState_NewData, + NextEventsR, Hibernate, [], Postponed, + Timers, _Seen, TimeoutEvents) -> + %% + S_1 = + S#state{ + state_data = NextState_NewData, + postponed = Postponed, + timers = Timers, + hibernate = Hibernate}, + case TimeoutEvents of + [] -> + loop_done(P, Debug, S_1, NextEventsR, Events); + _ -> + case Events of + [] -> + loop_prepend_timeout_events( + P, Debug, S_1, TimeoutEvents, + NextEventsR); + [E1] -> + loop_prepend_timeout_events( + P, Debug, S_1, TimeoutEvents, + [E1|NextEventsR]); + [E2,E1] -> + loop_prepend_timeout_events( + P, Debug, S_1, TimeoutEvents, + [E1,E2|NextEventsR]); + _ -> + loop_prepend_timeout_events( + P, Debug, S_1, TimeoutEvents, + lists:reverse(Events, NextEventsR)) + end + end; +loop_timeouts( + P, Debug, S, + Events, NextState_NewData, + NextEventsR, Hibernate, [Timeout|TimeoutsR], Postponed, + Timers, Seen, TimeoutEvents) -> + %% case Timeout of - {TimerType,Time,TimerMsg} -> - parse_timers( - TimerRefs, TimerTypes, CancelTimers, TimeoutsR, - Seen, TimeoutEvents, - TimerType, Time, TimerMsg); - Time -> - parse_timers( - TimerRefs, TimerTypes, CancelTimers, TimeoutsR, - Seen, TimeoutEvents, - timeout, Time, Time) + {TimeoutType,Time,TimeoutMsg} -> + %% Relative timeout + case Seen of + #{TimeoutType := _} -> + %% Type seen before - ignore + loop_timeouts( + 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, + TimeoutType, Time, TimeoutMsg, []) + end; + {TimeoutType,Time,TimeoutMsg,TimeoutOpts} -> + %% Absolute timeout + case Seen of + #{TimeoutType := _} -> + %% Type seen before - ignore + loop_timeouts( + 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, + TimeoutType, Time, TimeoutMsg, listify(TimeoutOpts)) + end + end. +%% +loop_timeouts( + 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); + 0 when TimeoutOpts =:= [] -> + %% Relative timeout zero + %% - cancel any running timer + %% handle timeout zero events later + %% + loop_timeouts_cancel( + P, Debug, S, + Events, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postponed, + Timers, Seen, [{TimeoutType,TimeoutMsg}|TimeoutEvents], + TimeoutType); + _ -> + %% (Re)start the timer + TimerRef = + erlang:start_timer(Time, self(), TimeoutMsg, TimeoutOpts), + {TimerRefs,TimeoutTypes} = Timers, + case TimeoutTypes of + #{TimeoutType := OldTimerRef} -> + %% Cancel the running timer, + %% update the timeout type, + %% insert the new timer ref, + %% and remove the old timer ref + Timers_1 = + {maps:remove( + OldTimerRef, + TimerRefs#{TimerRef => TimeoutType}), + TimeoutTypes#{TimeoutType := TimerRef}}, + cancel_timer(OldTimerRef), + 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 = + {TimerRefs#{TimerRef => TimeoutType}, + TimeoutTypes#{TimeoutType => TimerRef}}, + loop_timeouts( + P, Debug, S, + Events, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postponed, + Timers_1, Seen#{TimeoutType => true}, TimeoutEvents) + end end. -parse_timers( - TimerRefs, TimerTypes, CancelTimers, TimeoutsR, - Seen, TimeoutEvents, - TimerType, Time, TimerMsg) -> - 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); - 0 -> - %% 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), - 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); - #{} -> - parse_timers( - TimerRefs#{TimerRef => TimerType}, - TimerTypes#{TimerType => TimerRef}, - CancelTimers, TimeoutsR, - NewSeen, TimeoutEvents) - end - end +%% Loop helper to cancel a timeout +%% +loop_timeouts_cancel( + P, Debug, S, + Events, NextState_NewData, + NextEventsR, Hibernate, TimeoutsR, Postponed, + {TimerRefs,TimeoutTypes} = Timers, Seen, TimeoutEvents, + TimeoutType) -> + %% This function body should have been: + %% Timers_1 = cancel_timer_by_type(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 map:remove/2 within + %% cancel_timer_by_type/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 TimeoutTypes of + #{TimeoutType := TimerRef} -> + Timers_1 = + cancel_timer_by_ref_and_type( + TimerRef, TimeoutType, TimerRefs, TimeoutTypes), + 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. + +%% Continue state transition with prepending timeout zero events +%% before event queue reversal i.e appending timeout zero events +%% +loop_prepend_timeout_events(P, Debug, S, TimeoutEvents, EventsR) -> + {Debug_1,Events_1R} = + prepend_timeout_events(P, Debug, S, TimeoutEvents, EventsR), + loop_done(P, Debug_1, S, Events_1R, []). + +%% Place inserted events first in the event queue +%% +loop_done(P, Debug, S, NextEventsR, Events) -> + 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, 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 + [] -> + %% Get a new event + loop(P, Debug, S); + [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. %% Enqueue immediate timeout events (timeout 0 events) @@ -1508,72 +2061,102 @@ parse_timers( %% 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 +%% Other (state_timeout and {timeout,Name}) timeout 0 events +%% that are after an event timer timeout 0 event 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) -> +prepend_timeout_events(_P, Debug, _S, [], EventsR) -> + {Debug,EventsR}; +prepend_timeout_events( + P, Debug, S, [{timeout,_} = TimeoutEvent|TimeoutEvents], []) -> + %% Prepend this since there are no other events in queue + case Debug of + ?not_sys_debug -> + prepend_timeout_events( + P, Debug, S, TimeoutEvents, [TimeoutEvent]); + _ -> + {State,_Data} = S#state.state_data, + Debug_1 = + sys_debug( + Debug, P#params.name, {in,TimeoutEvent,State}), + prepend_timeout_events( + P, Debug_1, S, TimeoutEvents, [TimeoutEvent]) + end; +prepend_timeout_events( + P, Debug, S, [{timeout,_}|TimeoutEvents], EventsR) -> + %% Ignore since there are other events in queue + %% so they have cancelled the event timeout 0. + prepend_timeout_events(P, Debug, S, TimeoutEvents, EventsR); +prepend_timeout_events( + P, Debug, S, [TimeoutEvent|TimeoutEvents], EventsR) -> %% Just prepend all others - prepend_timeout_events(TimeoutEvents, [TimeoutEvent|EventsR]). + case Debug of + ?not_sys_debug -> + prepend_timeout_events( + P, Debug, S, TimeoutEvents, [TimeoutEvent|EventsR]); + _ -> + {State,_Data} = S#state.state_data, + Debug_1 = + sys_debug( + Debug, P#params.name, {in,TimeoutEvent,State}), + prepend_timeout_events( + P, Debug_1, S, TimeoutEvents, [TimeoutEvent|EventsR]) + end. %%--------------------------------------------------------------------------- %% Server helpers -reply_then_terminate( - Class, Reason, Stacktrace, Debug, - #{state := State} = S, Q, Replies) -> +reply_then_terminate(Class, Reason, Stacktrace, P, Debug, S, Q, Replies) -> do_reply_then_terminate( - Class, Reason, Stacktrace, Debug, - S, Q, listify(Replies), State). + Class, Reason, Stacktrace, P, Debug, S, Q, listify(Replies)). %% do_reply_then_terminate( - Class, Reason, Stacktrace, Debug, S, Q, [], _State) -> - terminate(Class, Reason, Stacktrace, Debug, S, Q); + Class, Reason, Stacktrace, P, Debug, S, Q, []) -> + terminate(Class, Reason, Stacktrace, P, Debug, S, Q); do_reply_then_terminate( - Class, Reason, Stacktrace, Debug, S, Q, [R|Rs], State) -> + Class, Reason, Stacktrace, P, Debug, S, Q, [R|Rs]) -> 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, Rs, State); + {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(), - Debug, S, Q) + P, Debug, S, Q) end. -do_reply(Debug, S, State, From, Reply) -> - reply(From, Reply), - sys_debug(Debug, S, State, {out,Reply,From}). - - terminate( - Class, Reason, Stacktrace, Debug, - #{module := Module, state := State, data := Data, postponed := P} = S, - Q) -> + Class, Reason, Stacktrace, + #params{module = 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 = erlang:get_stacktrace(), - error_info( - C, R, ST, S, Q, P, - format_status(terminate, get(), S)), - sys:print_log(Debug), + C:R:ST -> + error_info(C, R, ST, Debug, P, S, Q), erlang:raise(C, R, ST) end; false -> @@ -1582,16 +2165,13 @@ terminate( _ = case Reason of normal -> - sys_debug(Debug, S, State, {terminate,Reason}); + terminate_sys_debug(Debug, P, State, Reason); shutdown -> - sys_debug(Debug, S, State, {terminate,Reason}); + terminate_sys_debug(Debug, P, State, Reason); {shutdown,_} -> - sys_debug(Debug, S, State, {terminate,Reason}); + terminate_sys_debug(Debug, P, State, Reason); _ -> - error_info( - Class, Reason, Stacktrace, S, Q, P, - format_status(terminate, get(), S)), - sys:print_log(Debug) + error_info(Class, Reason, Stacktrace, Debug, P, S, Q) end, case Stacktrace of [] -> @@ -1600,12 +2180,67 @@ terminate( 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, - #{name := Name, - callback_mode := CallbackMode, - state_enter := StateEnter}, - Q, P, FmtData) -> + Class, Reason, Stacktrace, Debug, + #params{ + name = Name, + callback_mode = CallbackMode, + state_enter = StateEnter} = P, + #state{postponed = Postponed} = S, + Q) -> + Log = sys:get_log(Debug), + ?LOG_ERROR(#{label=>{gen_statem,terminate}, + name=>Name, + queue=>Q, + postponed=>Postponed, + callback_mode=>CallbackMode, + state_enter=>StateEnter, + state=>format_status(terminate, get(), P, S), + log=>Log, + reason=>{Class,Reason,Stacktrace}, + client_info=>client_stacktrace(Q)}, + #{domain=>[otp], + report_cb=>fun gen_statem:format_log/1, + error_logger=>#{tag=>error}}). + +client_stacktrace([]) -> + undefined; +client_stacktrace([{{call,{Pid,_Tag}},_Req}|_]) when is_pid(Pid) -> + if + node(Pid) =:= node() -> + 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; + true -> + {Pid,remote} + end; +client_stacktrace([_|_]) -> + undefined. + + +format_log(#{label:={gen_statem,terminate}, + name:=Name, + queue:=Q, + postponed:=Postponed, + callback_mode:=CallbackMode, + state_enter:=StateEnter, + state:=FmtData, + log:=Log, + reason:={Class,Reason,Stacktrace}, + client_info:=ClientInfo}) -> {FixedReason,FixedStacktrace} = case Stacktrace of [{M,F,Args,_}|ST] @@ -1625,12 +2260,12 @@ error_info( true -> {Reason,Stacktrace}; false -> - {{'function not exported',{M,F,Arity}}, - ST} + {{'function not exported',{M,F,Arity}},ST} end end; _ -> {Reason,Stacktrace} end, + {ClientFmt,ClientArgs} = format_client_log(ClientInfo), CBMode = case StateEnter of true -> @@ -1638,53 +2273,72 @@ error_info( false -> CallbackMode end, - error_logger:format( - "** State machine ~p terminating~n" ++ - case Q of - [] -> ""; - _ -> "** Last event = ~p~n" - end ++ - "** When server state = ~p~n" ++ - "** Reason for termination = ~w:~p~n" ++ - "** Callback mode = ~p~n" ++ - case Q of - [_,_|_] -> "** Queued = ~p~n"; - _ -> "" - end ++ - case P of - [] -> ""; - _ -> "** Postponed = ~p~n" - end ++ - case FixedStacktrace of - [] -> ""; - _ -> "** Stacktrace =~n** ~p~n" - end, - [Name | - case Q of - [] -> []; - [Event|_] -> [Event] - end] ++ - [FmtData, - Class,FixedReason, - CBMode] ++ - case Q of - [_|[_|_] = Events] -> [Events]; - _ -> [] - end ++ - case P of - [] -> []; - _ -> [P] - end ++ - case FixedStacktrace of - [] -> []; - _ -> [FixedStacktrace] - end). + {"** State machine ~tp terminating~n" ++ + case Q of + [] -> ""; + _ -> "** Last event = ~tp~n" + end ++ + "** When server state = ~tp~n" ++ + "** Reason for termination = ~w:~tp~n" ++ + "** Callback mode = ~p~n" ++ + case Q of + [_,_|_] -> "** Queued = ~tp~n"; + _ -> "" + end ++ + case Postponed of + [] -> ""; + _ -> "** Postponed = ~tp~n" + end ++ + case FixedStacktrace of + [] -> ""; + _ -> "** Stacktrace =~n** ~tp~n" + end ++ + case Log of + [] -> ""; + _ -> "** Log =~n** ~tp~n" + end ++ ClientFmt, + [Name | + case Q of + [] -> []; + [Event|_] -> [error_logger:limit_term(Event)] + end] ++ + [error_logger:limit_term(FmtData), + Class,error_logger:limit_term(FixedReason), + CBMode] ++ + case Q of + [_|[_|_] = Events] -> [error_logger:limit_term(Events)]; + _ -> [] + end ++ + case Postponed of + [] -> []; + _ -> [error_logger:limit_term(Postponed)] + end ++ + case FixedStacktrace of + [] -> []; + _ -> [error_logger:limit_term(FixedStacktrace)] + end ++ + case Log of + [] -> []; + _ -> [[error_logger:limit_term(T) || T <- Log]] + end ++ ClientArgs}. + +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, node(Pid)]}; +format_client_log({_Pid,{Name,Stacktrace}}) -> + {"** Client ~tp stacktrace~n" + "** ~tp~n", + [Name, error_logger:limit_term(Stacktrace)]}. %% Call Module:format_status/2 or return a default value format_status( Opt, PDict, - #{module := Module, state := State, data := Data}) -> + #params{module = 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]) @@ -1692,44 +2346,64 @@ format_status( Result -> Result; _:_ -> format_status_default( - Opt, State, - atom_to_list(Module) ++ ":format_status/2 crashed") + Opt, + {State, + atom_to_list(Module) ++ ":format_status/2 crashed"}) end; false -> - format_status_default(Opt, State, Data) + format_status_default(Opt, State_Data) end. -%% The default Module:format_status/2 -format_status_default(Opt, State, Data) -> - StateData = {State,Data}, +%% The default Module:format_status/3 +format_status_default(Opt, State_Data) -> case Opt of terminate -> - StateData; + State_Data; _ -> - [{data,[{"State",StateData}]}] + [{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). + +-compile({inline, [cancel_timer/1]}). +cancel_timer(TimerRef) -> + ?cancel_timer(TimerRef). + %% 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} +%% Remove the timer from Timers +-compile({inline, [cancel_timer_by_type/2]}). +cancel_timer_by_type(TimeoutType, {TimerRefs,TimeoutTypes} = Timers) -> + case TimeoutTypes of + #{TimeoutType := TimerRef} -> + ?cancel_timer(TimerRef), + {maps:remove(TimerRef, TimerRefs), + maps:remove(TimeoutType, TimeoutTypes)}; + #{} -> + Timers end. -cancel_timer(TimerRef) -> - ok = erlang:cancel_timer(TimerRef, [{async,true}]). +-compile({inline, [cancel_timer_by_ref_and_type/4]}). +cancel_timer_by_ref_and_type( + TimerRef, TimeoutType, TimerRefs, TimeoutTypes) -> + ?cancel_timer(TimerRef), + {maps:remove(TimerRef, TimerRefs), + maps:remove(TimeoutType, TimeoutTypes)}. |