From 30cae2492d8d8e927d57c0dc656ee2dfbec0a70c Mon Sep 17 00:00:00 2001 From: Raimo Niskanen Date: Mon, 13 Feb 2017 08:20:16 +0100 Subject: Implement {timeout,Name} timeouts --- lib/stdlib/doc/src/gen_statem.xml | 100 +++++++++++++++++++++++++++-------- lib/stdlib/src/gen_statem.erl | 79 +++++++++++++++------------ lib/stdlib/test/gen_statem_SUITE.erl | 70 +++++++++++++++++++++++- 3 files changed, 192 insertions(+), 57 deletions(-) (limited to 'lib') diff --git a/lib/stdlib/doc/src/gen_statem.xml b/lib/stdlib/doc/src/gen_statem.xml index 44ac1ad8ad..1b99b65e09 100644 --- a/lib/stdlib/doc/src/gen_statem.xml +++ b/lib/stdlib/doc/src/gen_statem.xml @@ -67,13 +67,16 @@ It has the same features and adds some really useful:

- State code is gathered. - The state can be any term. - Events can be postponed. - Events can be self-generated. - Automatic state enter code can be called. - A reply can be sent from a later state. - There can be multiple sys traceable replies. + Gathered state code. + Arbitrary term state. + Event postponing. + Self-generated events. + State time-out. + Multiple generic named time-outs. + Absolute time-out time. + Automatic state enter calls. + Reply from other state than the request. + Multiple sys traceable replies.

The callback model(s) for gen_statem differs from @@ -531,10 +534,12 @@ handle_event(_, _, State, Data) -> originate from the corresponding API functions. For calls, the event contains whom to reply to. Type info originates from regular process messages sent - to the gen_statem. Also, the state machine - implementation can generate events of types - timeout, state_timeout, - and internal to itself. + to the gen_statem. The state machine + implementation can, in addition to the above, + generate + events of types + timeout, {timeout,Name}, + state_timeout, and internal to itself.

@@ -701,13 +706,14 @@ handle_event(_, _, State, Data) ->

- Timeout timers - state_timeout() + Time-out timers + event_timeout(), + generic_timeout() and - event_timeout() + state_timeout() are handled. Time-outs with zero time are guaranteed to be delivered to the state machine before any external - not yet received event so if there is such a timeout requested, + not yet received event so if there is such a time-out requested, the corresponding time-out zero event is enqueued as the newest event.

@@ -795,8 +801,8 @@ handle_event(_, _, State, Data) -> erlang:start_timer/4 for how Time and Options - are interpreted. All Options of erlang:start_timer/4 - will not necessarily be supported in the future. + are interpreted. Future erlang:start_timer/4 Options + will not necessarily be supported.

Any event that arrives cancels this time-out. @@ -821,6 +827,42 @@ handle_event(_, _, State, Data) ->

+ + + +

+ Starts a timer set by + enter_action() + {timeout,Name}. + When the timer expires an event of + event_type() + {timeout,Name} will be generated. + See + erlang:start_timer/4 + for how Time and + Options + are interpreted. Future erlang:start_timer/4 Options + will not necessarily be supported. +

+

+ If Time is infinity, + no timer is started, as it never would expire anyway. +

+

+ If Time is relative and 0 + no timer is actually started, + instead the the time-out event is enqueued to ensure + that it gets processed before any not yet + received external event. +

+

+ Setting a timer with the same Name while it is running + will restart it with the new time-out value. + Therefore it is possible to cancel + a specific time-out by setting it to infinity. +

+ + @@ -835,8 +877,8 @@ handle_event(_, _, State, Data) -> erlang:start_timer/4 for how Time and Options - are interpreted. All Options of erlang:start_timer/4 - will not necessarily be supported in the future. + are interpreted. Future erlang:start_timer/4 Options + will not necessarily be supported.

If Time is infinity, @@ -861,7 +903,7 @@ handle_event(_, _, State, Data) ->

If Abs is true an absolute timer is started, - and if it false a relative, which is the default. + and if it is false a relative, which is the default. See erlang:start_timer/4 for details. @@ -986,7 +1028,19 @@ handle_event(_, _, State, Data) -> transition_option() event_timeout() to Time with EventContent - and options + and time-out options + Options. +

+ + {timeout,Name} + +

+ Sets the + transition_option() + generic_timeout() + to Time for Name + with EventContent + and time-out options Options.

@@ -997,7 +1051,7 @@ handle_event(_, _, State, Data) -> transition_option() state_timeout() to Time with EventContent - and options + and time-out options Options.

@@ -1270,7 +1324,7 @@ handle_event(_, _, State, Data) -> to avoid that the calling process dies when the call times out, you will have to be prepared to handle a late reply. - So why not just allow the calling process to die? + So why not just let the calling process die?

diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl index fe80bb5de4..6f566b8beb 100644 --- a/lib/stdlib/src/gen_statem.erl +++ b/lib/stdlib/src/gen_statem.erl @@ -78,8 +78,9 @@ -type data() :: term(). -type event_type() :: - {'call',From :: from()} | 'cast' | - 'info' | 'timeout' | 'state_timeout' | 'internal'. + {'call',From :: from()} | 'cast' | 'info' | + 'timeout' | {'timeout', Name :: term()} | 'state_timeout' | + 'internal'. -type callback_mode_result() :: callback_mode() | [callback_mode() | state_enter()]. @@ -88,7 +89,7 @@ -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 (=/=) @@ -100,6 +101,9 @@ %% Generate a ('timeout', EventContent, ...) event %% unless some other event is delivered Time :: timeout() | integer(). +-type generic_timeout() :: + %% Generate a ({'timeout',Name}, EventContent, ...) event + Time :: timeout() | integer(). -type state_timeout() :: %% Generate a ('state_timeout', EventContent, ...) event %% unless the state is changed @@ -142,6 +146,14 @@ Time :: event_timeout(), EventContent :: term(), Options :: (timeout_option() | [timeout_option()])} | + %% + {{'timeout', Name :: term()}, % Set the generic_timeout option + Time :: generic_timeout(), EventContent :: term()} | + {{'timeout', Name :: term()}, % Set the generic_timeout option + Time :: generic_timeout(), + EventContent :: term(), + Options :: (timeout_option() | [timeout_option()])} | + %% {'state_timeout', % Set the state_timeout option Time :: state_timeout(), EventContent :: term()} | {'state_timeout', % Set the state_timeout option @@ -311,37 +323,26 @@ %% 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 - {call,From} -> - from(From); - cast -> - true; - info -> - true; - timeout -> - true; - state_timeout -> - true; - internal -> - true; - _ -> - false + {call,From} -> from(From); + cast -> true; + info -> true; + timeout -> true; + state_timeout -> true; + internal -> true; + {timeout,_} -> true; + _ -> false end. @@ -1387,15 +1388,27 @@ parse_actions( ?STACKTRACE()} end; %% - {TimerType,_,_} = Timeout - when TimerType =:= timeout; - TimerType =:= state_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); + {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); - {TimerType,_,_,_} = Timeout - when TimerType =:= timeout; - TimerType =:= state_timeout -> + {state_timeout,_,_,_} = Timeout -> parse_actions_timeout( Debug, S, State, Actions, Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout); diff --git a/lib/stdlib/test/gen_statem_SUITE.erl b/lib/stdlib/test/gen_statem_SUITE.erl index ee61099155..36b1f761a7 100644 --- a/lib/stdlib/test/gen_statem_SUITE.erl +++ b/lib/stdlib/test/gen_statem_SUITE.erl @@ -38,7 +38,7 @@ all() -> {group, abnormal}, {group, abnormal_handle_event}, shutdown, stop_and_reply, state_enter, event_order, - state_timeout, event_types, code_change, + state_timeout, event_types, generic_timers, code_change, {group, sys}, hibernate, enter_loop]. @@ -834,6 +834,7 @@ event_types(_Config) -> {next_event,timeout,3}, {next_event,info,4}, {next_event,cast,5}, + {next_event,{timeout,6}, 6}, {next_event,Call,Req}]} end, state1 => @@ -857,6 +858,10 @@ event_types(_Config) -> {next_state, state6, undefined} end, state6 => + fun ({timeout,6}, 6, undefined) -> + {next_state, state7, undefined} + end, + state7 => fun ({call,From}, stop, undefined) -> {stop_and_reply, shutdown, [{reply,From,stopped}]} @@ -884,6 +889,69 @@ event_types(_Config) -> +generic_timers(_Config) -> + process_flag(trap_exit, true), + + Machine = + %% Abusing the internal format of From... + #{init => + fun () -> + {ok, start, undefined} + end, + start => + fun ({call,_} = Call, Req, undefined) -> + {next_state, state1, undefined, + [{{timeout,a},1500,1}, + {state_timeout,1500,1}, + {{timeout,b},1000,1}, + {next_event,Call,Req}]} + end, + state1 => + fun ({call,_} = Call, Req, undefined) -> + T = erlang:monotonic_time(millisecond) + 500, + {next_state, state2, undefined, + [{{timeout,c},T,2,{abs,true}}, + {{timeout,d},0,2,[{abs,false}]}, + {timeout,0,2}, + {{timeout,b},infinity,2}, + {{timeout,a},1000,{Call,Req}}]} + end, + state2 => + fun ({timeout,d}, 2, undefined) -> + {next_state, state3, undefined} + end, + state3 => + fun ({timeout,c}, 2, undefined) -> + {next_state, state4, undefined} + end, + state4 => + fun ({timeout,a}, {{call,From},stop}, undefined) -> + {stop_and_reply, shutdown, + [{reply,From,stopped}]} + end}, + {ok,STM} = + gen_statem:start_link( + ?MODULE, {map_statem,Machine,[]}, [{debug,[trace]}]), + + stopped = gen_statem:call(STM, stop), + receive + {'EXIT',STM,shutdown} -> + ok + after 500 -> + ct:fail(did_not_stop) + end, + + {noproc,_} = + ?EXPECT_FAILURE(gen_statem:call(STM, hej), Reason), + case flush() of + [] -> + ok; + Other2 -> + ct:fail({unexpected,Other2}) + end. + + + sys1(Config) -> {ok,Pid} = gen_statem:start(?MODULE, start_arg(Config, []), []), {status, Pid, {module,gen_statem}, _} = sys:get_status(Pid), -- cgit v1.2.3