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authorRaimo Niskanen <raimo@erlang.org>2017-04-28 11:28:59 +0200
committerRaimo Niskanen <raimo@erlang.org>2017-04-28 11:28:59 +0200
commit3c4e69029ace241f82eb057c219f2942e6c4dd33 (patch)
tree6177cd4f95cde1212662a87b76fb47f34c8a9d31
parente069941a410f61cf6ba981ef6ae10e467b9c616c (diff)
parenteff1ee5ebf1d767d610cd6bc059e5f4dea57d2af (diff)
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Merge branch 'raimo/gen_statem-dev'
OTP-14531 Generic time-outs in gen_statem Conflicts: lib/stdlib/test/erl_internal_SUITE.erl
-rw-r--r--lib/stdlib/doc/src/gen_statem.xml190
-rw-r--r--lib/stdlib/src/gen_statem.erl207
-rw-r--r--lib/stdlib/test/erl_internal_SUITE.erl11
-rw-r--r--lib/stdlib/test/gen_statem_SUITE.erl139
-rw-r--r--lib/stdlib/test/gen_statem_SUITE_data/oc_statem.erl37
-rw-r--r--system/doc/design_principles/statem.xml115
6 files changed, 562 insertions, 137 deletions
diff --git a/lib/stdlib/doc/src/gen_statem.xml b/lib/stdlib/doc/src/gen_statem.xml
index 18089a8191..17a3a3c83c 100644
--- a/lib/stdlib/doc/src/gen_statem.xml
+++ b/lib/stdlib/doc/src/gen_statem.xml
@@ -4,7 +4,7 @@
<erlref>
<header>
<copyright>
- <year>2016-2017</year>
+ <year>2016</year><year>2017</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -67,13 +67,16 @@
It has the same features and adds some really useful:
</p>
<list type="bulleted">
- <item>State code is gathered.</item>
- <item>The state can be any term.</item>
- <item>Events can be postponed.</item>
- <item>Events can be self-generated.</item>
- <item>Automatic state enter code can be called.</item>
- <item>A reply can be sent from a later state.</item>
- <item>There can be multiple <c>sys</c> traceable replies.</item>
+ <item>Gathered state code.</item>
+ <item>Arbitrary term state.</item>
+ <item>Event postponing.</item>
+ <item>Self-generated events.</item>
+ <item>State time-out.</item>
+ <item>Multiple generic named time-outs.</item>
+ <item>Absolute time-out time.</item>
+ <item>Automatic state enter calls.</item>
+ <item>Reply from other state than the request.</item>
+ <item>Multiple <c>sys</c> traceable replies.</item>
</list>
<p>
The callback model(s) for <c>gen_statem</c> differs from
@@ -148,7 +151,7 @@ erlang:'!' -----> Module:StateName/3
This gathers all code for a specific state
in one function as the <c>gen_statem</c> engine
branches depending on state name.
- Notice the fact that there is a mandatory callback function
+ Note the fact that the callback function
<seealso marker="#Module:terminate/3"><c>Module:terminate/3</c></seealso>
makes the state name <c>terminate</c> unusable in this mode.
</p>
@@ -533,10 +536,12 @@ handle_event(_, _, State, Data) ->
originate from the corresponding API functions.
For calls, the event contains whom to reply to.
Type <c>info</c> originates from regular process messages sent
- to the <c>gen_statem</c>. Also, the state machine
- implementation can generate events of types
- <c>timeout</c>, <c>state_timeout</c>,
- and <c>internal</c> to itself.
+ to the <c>gen_statem</c>. The state machine
+ implementation can, in addition to the above,
+ generate
+ <seealso marker="#type-event_type"><c>events of types</c></seealso>
+ <c>timeout</c>, <c>{timeout,<anno>Name</anno>}</c>,
+ <c>state_timeout</c>, and <c>internal</c> to itself.
</p>
</desc>
</datatype>
@@ -703,13 +708,14 @@ handle_event(_, _, State, Data) ->
</item>
<item>
<p>
- Timeout timers
- <seealso marker="#type-state_timeout"><c>state_timeout()</c></seealso>
+ Time-out timers
+ <seealso marker="#type-event_timeout"><c>event_timeout()</c></seealso>,
+ <seealso marker="#type-generic_timeout"><c>generic_timeout()</c></seealso>
and
- <seealso marker="#type-event_timeout"><c>event_timeout()</c></seealso>
+ <seealso marker="#type-state_timeout"><c>state_timeout()</c></seealso>
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.
</p>
@@ -787,49 +793,102 @@ handle_event(_, _, State, Data) ->
<name name="event_timeout"/>
<desc>
<p>
- Generates an event of
+ Starts a timer set by
+ <seealso marker="#type-enter_action"><c>enter_action()</c></seealso>
+ <c>timeout</c>.
+ When the timer expires an event of
<seealso marker="#type-event_type"><c>event_type()</c></seealso>
- <c>timeout</c>
- after this time (in milliseconds) unless another
- event arrives or has arrived
- in which case this time-out is cancelled.
+ <c>timeout</c> will be generated.
+ See
+ <seealso marker="erts:erlang#start_timer/4"><c>erlang:start_timer/4</c></seealso>
+ for how <c>Time</c> and
+ <seealso marker="#type-timeout_option"><c>Options</c></seealso>
+ are interpreted. Future <c>erlang:start_timer/4</c> <c>Options</c>
+ will not necessarily be supported.
+ </p>
+ <p>
+ Any event that arrives cancels this time-out.
Note that a retried or inserted event counts as arrived.
So does a state time-out zero event, if it was generated
- before this timer is requested.
+ before this time-out is requested.
</p>
<p>
- If the value is <c>infinity</c>, no timer is started, as
- it never would trigger anyway.
+ If <c>Time</c> is <c>infinity</c>,
+ no timer is started, as it never would expire anyway.
</p>
<p>
- If the value is <c>0</c> no timer is actually started,
+ If <c>Time</c> is relative and <c>0</c>
+ 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.
</p>
<p>
- Note that it is not possible or needed to cancel this time-out,
+ Note that it is not possible nor needed to cancel this time-out,
as it is cancelled automatically by any other event.
</p>
</desc>
</datatype>
<datatype>
+ <name name="generic_timeout"/>
+ <desc>
+ <p>
+ Starts a timer set by
+ <seealso marker="#type-enter_action"><c>enter_action()</c></seealso>
+ <c>{timeout,Name}</c>.
+ When the timer expires an event of
+ <seealso marker="#type-event_type"><c>event_type()</c></seealso>
+ <c>{timeout,Name}</c> will be generated.
+ See
+ <seealso marker="erts:erlang#start_timer/4"><c>erlang:start_timer/4</c></seealso>
+ for how <c>Time</c> and
+ <seealso marker="#type-timeout_option"><c>Options</c></seealso>
+ are interpreted. Future <c>erlang:start_timer/4</c> <c>Options</c>
+ will not necessarily be supported.
+ </p>
+ <p>
+ If <c>Time</c> is <c>infinity</c>,
+ no timer is started, as it never would expire anyway.
+ </p>
+ <p>
+ If <c>Time</c> is relative and <c>0</c>
+ 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.
+ </p>
+ <p>
+ Setting a timer with the same <c>Name</c> 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 <c>infinity</c>.
+ </p>
+ </desc>
+ </datatype>
+ <datatype>
<name name="state_timeout"/>
<desc>
<p>
- Generates an event of
+ Starts a timer set by
+ <seealso marker="#type-enter_action"><c>enter_action()</c></seealso>
+ <c>state_timeout</c>.
+ When the timer expires an event of
<seealso marker="#type-event_type"><c>event_type()</c></seealso>
- <c>state_timeout</c>
- after this time (in milliseconds) unless the <c>gen_statem</c>
- changes states (<c>NewState =/= OldState</c>)
- which case this time-out is cancelled.
+ <c>state_timeout</c> will be generated.
+ See
+ <seealso marker="erts:erlang#start_timer/4"><c>erlang:start_timer/4</c></seealso>
+ for how <c>Time</c> and
+ <seealso marker="#type-timeout_option"><c>Options</c></seealso>
+ are interpreted. Future <c>erlang:start_timer/4</c> <c>Options</c>
+ will not necessarily be supported.
</p>
<p>
- If the value is <c>infinity</c>, no timer is started, as
- it never would trigger anyway.
+ If <c>Time</c> is <c>infinity</c>,
+ no timer is started, as it never would expire anyway.
</p>
<p>
- If the value is <c>0</c> no timer is actually started,
+ If <c>Time</c> is relative and <c>0</c>
+ 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.
@@ -842,6 +901,20 @@ handle_event(_, _, State, Data) ->
</desc>
</datatype>
<datatype>
+ <name name="timeout_option"/>
+ <desc>
+ <p>
+ If <c>Abs</c> is <c>true</c> an absolute timer is started,
+ and if it is <c>false</c> a relative, which is the default.
+ See
+ <seealso marker="erts:erlang#start_timer/4"><c>erlang:start_timer/4</c></seealso>
+ for details.
+ </p>
+ <p>
+ </p>
+ </desc>
+ </datatype>
+ <datatype>
<name name="action"/>
<desc>
<p>
@@ -955,7 +1028,21 @@ handle_event(_, _, State, Data) ->
Sets the
<seealso marker="#type-transition_option"><c>transition_option()</c></seealso>
<seealso marker="#type-event_timeout"><c>event_timeout()</c></seealso>
- to <c><anno>Time</anno></c> with <c><anno>EventContent</anno></c>.
+ to <c><anno>Time</anno></c> with <c><anno>EventContent</anno></c>
+ and time-out options
+ <seealso marker="#type-timeout_option"><c><anno>Options</anno></c></seealso>.
+ </p>
+ </item>
+ <tag><c>{timeout,<anno>Name</anno>}</c></tag>
+ <item>
+ <p>
+ Sets the
+ <seealso marker="#type-transition_option"><c>transition_option()</c></seealso>
+ <seealso marker="#type-generic_timeout"><c>generic_timeout()</c></seealso>
+ to <c><anno>Time</anno></c> for <c><anno>Name</anno></c>
+ with <c><anno>EventContent</anno></c>
+ and time-out options
+ <seealso marker="#type-timeout_option"><c><anno>Options</anno></c></seealso>.
</p>
</item>
<tag><c>state_timeout</c></tag>
@@ -964,7 +1051,9 @@ handle_event(_, _, State, Data) ->
Sets the
<seealso marker="#type-transition_option"><c>transition_option()</c></seealso>
<seealso marker="#type-state_timeout"><c>state_timeout()</c></seealso>
- to <c><anno>Time</anno></c> with <c><anno>EventContent</anno></c>.
+ to <c><anno>Time</anno></c> with <c><anno>EventContent</anno></c>
+ and time-out options
+ <seealso marker="#type-timeout_option"><c><anno>Options</anno></c></seealso>.
</p>
</item>
</taglist>
@@ -1236,7 +1325,7 @@ 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?
</p>
</note>
<p>
@@ -1645,6 +1734,16 @@ handle_event(_, _, State, Data) ->
<v>Reason = term()</v>
</type>
<desc>
+ <note>
+ <p>
+ This callback is optional, so callback modules need not export it.
+ If a release upgrade/downgrade with
+ <c>Change={advanced,Extra}</c>
+ specified in the <c>.appup</c> file is made
+ when <c>code_change/4</c> is not implemented
+ the process will crash with exit reason <c>undef</c>.
+ </p>
+ </note>
<p>
This function is called by a <c>gen_statem</c> when it is to
update its internal state during a release upgrade/downgrade,
@@ -1705,7 +1804,7 @@ handle_event(_, _, State, Data) ->
<func>
<name>Module:init(Args) -> Result(StateType)</name>
<fsummary>
- Optional function for initializing process and internal state.
+ Initializing process and internal state.
</fsummary>
<type>
<v>Args = term()</v>
@@ -1721,7 +1820,7 @@ handle_event(_, _, State, Data) ->
<seealso marker="#start_link/3"><c>start_link/3,4</c></seealso>
or
<seealso marker="#start/3"><c>start/3,4</c></seealso>,
- this optional function is called by the new process to initialize
+ this function is called by the new process to initialize
the implementation state and server data.
</p>
<p>
@@ -1730,13 +1829,16 @@ handle_event(_, _, State, Data) ->
</p>
<note>
<p>
- This callback is optional, so a callback module does not need
- to export it, but most do. If this function is not exported,
- the <c>gen_statem</c> should be started through
+ Note that if the <c>gen_statem</c> is started trough
<seealso marker="proc_lib"><c>proc_lib</c></seealso>
and
- <seealso marker="#enter_loop/4"><c>enter_loop/4-6</c></seealso>.
+ <seealso marker="#enter_loop/4"><c>enter_loop/4-6</c></seealso>,
+ this callback will never be called.
+ Since this callback is not optional it can
+ in that case be implemented as:
</p>
+ <pre>
+init(Args) -> erlang:error(not_implemented, [Args]).</pre>
</note>
</desc>
</func>
diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl
index cacc932ec4..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 (=/=)
@@ -97,13 +98,17 @@
%% If 'true' hibernate the server instead of going into receive
boolean().
-type event_timeout() ::
- %% Generate a ('timeout', EventContent, ...) event after Time
+ %% Generate a ('timeout', EventContent, ...) event
%% unless some other event is delivered
- Time :: timeout().
+ Time :: timeout() | integer().
+-type generic_timeout() ::
+ %% Generate a ({'timeout',Name}, EventContent, ...) event
+ Time :: timeout() | integer().
-type state_timeout() ::
- %% Generate a ('state_timeout', EventContent, ...) event 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:
@@ -137,8 +142,24 @@
(Timeout :: event_timeout()) | % {timeout,Timeout}
{'timeout', % Set the event_timeout option
Time :: event_timeout(), EventContent :: term()} |
+ {'timeout', % Set the event_timeout option
+ Time :: event_timeout(),
+ EventContent :: term(),
+ Options :: (timeout_option() | [timeout_option()])} |
+ %%
+ {{'timeout', Name :: term()}, % Set the generic_timeout option
+ Time :: generic_timeout(), EventContent :: term()} |
+ {{'timeout', Name :: term()}, % Set the generic_timeout option
+ Time :: generic_timeout(),
+ EventContent :: term(),
+ Options :: (timeout_option() | [timeout_option()])} |
+ %%
{'state_timeout', % Set the state_timeout option
Time :: state_timeout(), EventContent :: term()} |
+ {'state_timeout', % Set the state_timeout option
+ Time :: state_timeout(),
+ EventContent :: term(),
+ Options :: (timeout_option() | [timeout_option()])} |
%%
reply_action().
-type reply_action() ::
@@ -287,8 +308,7 @@
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
%%
@@ -303,37 +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.
@@ -1313,7 +1322,7 @@ parse_enter_actions(Debug, S, State, Actions, Hibernate, TimeoutsR) ->
parse_actions(Debug, S, State, Actions) ->
Hibernate = false,
- TimeoutsR = [{timeout,infinity,infinity}], %% Will cancel event timer
+ TimeoutsR = [infinity], %% Will cancel event timer
Postpone = false,
NextEventsR = [],
parse_actions(
@@ -1379,7 +1388,11 @@ parse_actions(
?STACKTRACE()}
end;
%%
- {state_timeout,_,_} = 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);
@@ -1387,6 +1400,18 @@ parse_actions(
parse_actions_timeout(
Debug, S, State, Actions,
Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
+ {timeout,_,_,_} = Timeout ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
+ {state_timeout,_,_} = Timeout ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
+ {state_timeout,_,_,_} = Timeout ->
+ parse_actions_timeout(
+ Debug, S, State, Actions,
+ Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout);
Time ->
parse_actions_timeout(
Debug, S, State, Actions,
@@ -1396,26 +1421,64 @@ parse_actions(
parse_actions_timeout(
Debug, S, State, Actions,
Hibernate, TimeoutsR, Postpone, NextEventsR, Timeout) ->
- Time =
- case Timeout of
- {_,T,_} -> T;
- T -> T
- 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 Timeout of
+ {TimerType,Time,TimerMsg,TimerOpts} ->
+ case validate_timer_args(Time, listify(TimerOpts)) of
+ true ->
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, [Timeout|TimeoutsR],
+ Postpone, NextEventsR);
+ false ->
+ NewTimeout = {TimerType,Time,TimerMsg},
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, [NewTimeout|TimeoutsR],
+ Postpone, NextEventsR);
+ error ->
+ {error,
+ {bad_action_from_state_function,Timeout},
+ ?STACKTRACE()}
+ end;
+ {_,Time,_} ->
+ case validate_timer_args(Time, []) of
+ false ->
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, [Timeout|TimeoutsR],
+ Postpone, NextEventsR);
+ error ->
+ {error,
+ {bad_action_from_state_function,Timeout},
+ ?STACKTRACE()}
+ end;
+ Time ->
+ case validate_timer_args(Time, []) of
+ false ->
+ parse_actions(
+ Debug, S, State, Actions,
+ Hibernate, [Timeout|TimeoutsR],
+ Postpone, NextEventsR);
+ error ->
+ {error,
+ {bad_action_from_state_function,Timeout},
+ ?STACKTRACE()}
+ end
end.
-validate_time(Time) when is_integer(Time), Time >= 0 -> true;
-validate_time(infinity) -> true;
-validate_time(_) -> false.
+validate_timer_args(Time, Opts) ->
+ validate_timer_args(Time, Opts, false).
+%%
+validate_timer_args(Time, [], true) when is_integer(Time) ->
+ true;
+validate_timer_args(Time, [], false) when is_integer(Time), Time >= 0 ->
+ false;
+validate_timer_args(infinity, [], Abs) ->
+ Abs;
+validate_timer_args(Time, [{abs,Abs}|Opts], _) when is_boolean(Abs) ->
+ validate_timer_args(Time, Opts, Abs);
+validate_timer_args(_, [_|_], _) ->
+ error.
%% Stop and start timers as well as create timeout zero events
%% and pending event timer
@@ -1431,22 +1494,39 @@ parse_timers(
TimerRefs, TimerTypes, CancelTimers, [Timeout|TimeoutsR],
Seen, TimeoutEvents) ->
case Timeout of
+ {TimerType,Time,TimerMsg,TimerOpts} ->
+ %% Absolute timer
+ parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ TimerType, Time, TimerMsg, listify(TimerOpts));
+ %% Relative timers below
+ {TimerType,0,TimerMsg} ->
+ parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ TimerType, zero, TimerMsg, []);
{TimerType,Time,TimerMsg} ->
parse_timers(
- TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
- Seen, TimeoutEvents,
- TimerType, Time, TimerMsg);
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ TimerType, Time, TimerMsg, []);
+ 0 ->
+ parse_timers(
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ timeout, zero, 0, []);
Time ->
parse_timers(
- TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
- Seen, TimeoutEvents,
- timeout, Time, Time)
+ TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
+ Seen, TimeoutEvents,
+ timeout, Time, Time, [])
end.
parse_timers(
TimerRefs, TimerTypes, CancelTimers, TimeoutsR,
Seen, TimeoutEvents,
- TimerType, Time, TimerMsg) ->
+ TimerType, Time, TimerMsg, TimerOpts) ->
case Seen of
#{TimerType := _} ->
%% Type seen before - ignore
@@ -1465,7 +1545,7 @@ parse_timers(
parse_timers(
TimerRefs, NewTimerTypes, NewCancelTimers, TimeoutsR,
NewSeen, TimeoutEvents);
- 0 ->
+ zero ->
%% Cancel any running timer
{NewTimerTypes,NewCancelTimers} =
cancel_timer_by_type(
@@ -1478,7 +1558,8 @@ parse_timers(
_ ->
%% (Re)start the timer
TimerRef =
- erlang:start_timer(Time, self(), TimerMsg),
+ erlang:start_timer(
+ Time, self(), TimerMsg, TimerOpts),
case TimerTypes of
#{TimerType := OldTimerRef} ->
%% Cancel the running timer
@@ -1492,6 +1573,8 @@ parse_timers(
NewCancelTimers, TimeoutsR,
NewSeen, TimeoutEvents);
#{} ->
+ %% Insert the new timer into
+ %% both TimerRefs and TimerTypes
parse_timers(
TimerRefs#{TimerRef => TimerType},
TimerTypes#{TimerType => TimerRef},
diff --git a/lib/stdlib/test/erl_internal_SUITE.erl b/lib/stdlib/test/erl_internal_SUITE.erl
index 099f21f905..789a9d4363 100644
--- a/lib/stdlib/test/erl_internal_SUITE.erl
+++ b/lib/stdlib/test/erl_internal_SUITE.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1999-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1999-2017. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
@@ -60,7 +60,7 @@ end_per_testcase(_Case, _Config) ->
%% Check that the behaviour callbacks are correctly defined.
behav(_) ->
Modules = [application, gen_server, gen_fsm, gen_event,
- supervisor_bridge, supervisor],
+ gen_statem, supervisor_bridge, supervisor],
lists:foreach(fun check_behav/1, Modules).
check_behav(Module) ->
@@ -89,6 +89,10 @@ callbacks(gen_event) ->
[{init,1}, {handle_event,2}, {handle_call,2},
{handle_info,2}, {terminate,2}, {code_change,3},
{format_status,2}];
+callbacks(gen_statem) ->
+ [{init, 1}, {callback_mode, 0}, {state_name, 3},
+ {handle_event, 4}, {terminate, 3}, {code_change, 4},
+ {format_status, 2}];
callbacks(supervisor_bridge) ->
[{init,1}, {terminate,2}];
callbacks(supervisor) ->
@@ -102,6 +106,9 @@ optional_callbacks(gen_fsm) ->
[{handle_info, 3}, {terminate, 3}, {code_change, 4}, {format_status, 2}];
optional_callbacks(gen_event) ->
[{handle_info, 2}, {terminate, 2}, {code_change, 3}, {format_status, 2}];
+optional_callbacks(gen_statem) ->
+ [{state_name, 3}, {handle_event, 4},
+ {terminate, 3}, {code_change, 4}, {format_status, 2}];
optional_callbacks(supervisor_bridge) ->
[];
optional_callbacks(supervisor) ->
diff --git a/lib/stdlib/test/gen_statem_SUITE.erl b/lib/stdlib/test/gen_statem_SUITE.erl
index ac27c9fc79..05934b3953 100644
--- a/lib/stdlib/test/gen_statem_SUITE.erl
+++ b/lib/stdlib/test/gen_statem_SUITE.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 2016. All Rights Reserved.
+%% Copyright Ericsson AB 2016-2017. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
@@ -38,9 +38,10 @@ 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].
+ hibernate, enter_loop, {group, undef_callbacks},
+ undef_in_terminate].
groups() ->
[{start, [], tcs(start)},
@@ -50,7 +51,8 @@ groups() ->
{abnormal, [], tcs(abnormal)},
{abnormal_handle_event, [], tcs(abnormal)},
{sys, [], tcs(sys)},
- {sys_handle_event, [], tcs(sys)}].
+ {sys_handle_event, [], tcs(sys)},
+ {undef_callbacks, [], tcs(undef_callbacks)}].
tcs(start) ->
[start1, start2, start3, start4, start5, start6, start7,
@@ -62,8 +64,9 @@ tcs(abnormal) ->
tcs(sys) ->
[sys1, call_format_status,
error_format_status, terminate_crash_format,
- get_state, replace_state].
-
+ get_state, replace_state];
+tcs(undef_callbacks) ->
+ [undef_code_change, undef_terminate1, undef_terminate2].
init_per_suite(Config) ->
Config.
@@ -77,6 +80,11 @@ init_per_group(GroupName, Config)
GroupName =:= abnormal_handle_event;
GroupName =:= sys_handle_event ->
[{callback_mode,handle_event_function}|Config];
+init_per_group(undef_callbacks, Config) ->
+ DataDir = ?config(data_dir, Config),
+ StatemPath = filename:join(DataDir, "oc_statem.erl"),
+ {ok, oc_statem} = compile:file(StatemPath),
+ Config;
init_per_group(_GroupName, Config) ->
Config.
@@ -834,6 +842,7 @@ 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 +866,10 @@ 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 +897,69 @@ 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),
@@ -1393,6 +1469,51 @@ enter_loop(Reg1, Reg2) ->
gen_statem:enter_loop(?MODULE, [], state0, [])
end.
+undef_code_change(_Config) ->
+ {ok, Statem} = gen_statem:start(oc_statem, [], []),
+ {error, {'EXIT',
+ {undef, [{oc_statem, code_change, [_, _, _, _], _}|_]}}}
+ = fake_upgrade(Statem, oc_statem).
+
+fake_upgrade(Pid, Mod) ->
+ sys:suspend(Pid),
+ sys:replace_state(Pid, fun(State) -> {new, State} end),
+ Ret = sys:change_code(Pid, Mod, old_vsn, []),
+ ok = sys:resume(Pid),
+ Ret.
+
+undef_terminate1(_Config) ->
+ {ok, Statem} = gen_statem:start(oc_statem, [], []),
+ MRef = monitor(process, Statem),
+ ok = gen_statem:stop(Statem),
+ verify_down(Statem, MRef, normal),
+ ok.
+
+undef_terminate2(_Config) ->
+ Reason = {error, test},
+ {ok, Statem} = oc_statem:start(),
+ MRef = monitor(process, Statem),
+ ok = gen_statem:stop(Statem, Reason, infinity),
+ verify_down(Statem, MRef, Reason).
+
+undef_in_terminate(_Config) ->
+ Data = {undef_in_terminate, {?MODULE, terminate}},
+ {ok, Statem} = gen_statem:start(?MODULE, {data, Data}, []),
+ try
+ gen_statem:stop(Statem),
+ ct:fail(should_crash)
+ catch
+ exit:{undef, [{?MODULE, terminate, _, _}|_]} ->
+ ok
+ end.
+
+verify_down(Statem, MRef, Reason) ->
+ receive
+ {'DOWN', MRef, process, Statem, Reason} ->
+ ok
+ after 5000 ->
+ ct:fail(default_terminate_failed)
+ end.
%% Test the order for multiple {next_event,T,C}
next_events(Config) ->
@@ -1571,6 +1692,9 @@ callback_mode() ->
terminate(_, _State, crash_terminate) ->
exit({crash,terminate});
+terminate(_, _State, {undef_in_terminate, {Mod, Fun}}) ->
+ Mod:Fun(),
+ ok;
terminate({From,stopped}, State, _Data) ->
From ! {self(),{stopped,State}},
ok;
@@ -1597,8 +1721,9 @@ idle({call,From}, {delayed_answer,T}, Data) ->
throw({keep_state,Data})
end;
idle({call,From}, {timeout,Time}, _Data) ->
+ AbsTime = erlang:monotonic_time(millisecond) + Time,
{next_state,timeout,{From,Time},
- {timeout,Time,idle}};
+ {timeout,AbsTime,idle,[{abs,true}]}};
idle(cast, next_event, _Data) ->
{next_state,next_events,[a,b,c],
[{next_event,internal,a},
diff --git a/lib/stdlib/test/gen_statem_SUITE_data/oc_statem.erl b/lib/stdlib/test/gen_statem_SUITE_data/oc_statem.erl
new file mode 100644
index 0000000000..27c9e0718d
--- /dev/null
+++ b/lib/stdlib/test/gen_statem_SUITE_data/oc_statem.erl
@@ -0,0 +1,37 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%% http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(oc_statem).
+
+-behaviour(gen_statem).
+
+%% API
+-export([start/0]).
+
+%% gen_statem callbacks
+-export([init/1, callback_mode/0]).
+
+start() ->
+ gen_statem:start({local, ?MODULE}, ?MODULE, [], []).
+
+init([]) ->
+ {ok, state_name, #{}}.
+
+callback_mode() ->
+ handle_event_function.
diff --git a/system/doc/design_principles/statem.xml b/system/doc/design_principles/statem.xml
index f4d84ab163..0667af7868 100644
--- a/system/doc/design_principles/statem.xml
+++ b/system/doc/design_principles/statem.xml
@@ -4,7 +4,7 @@
<chapter>
<header>
<copyright>
- <year>2016</year>
+ <year>2016</year><year>2017</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -293,6 +293,13 @@ StateName(EventType, EventContent, Data) ->
<seealso marker="#State Time-Outs">State Time-Outs</seealso>
</item>
<item>
+ Start a
+ <seealso marker="stdlib:gen_statem#type-generic_timeout">
+ generic time-out</seealso>,
+ read more in section
+ <seealso marker="#Generic Time-Outs">Generic Time-Outs</seealso>
+ </item>
+ <item>
Start an
<seealso marker="stdlib:gen_statem#type-event_timeout">event time-out</seealso>,
see more in section
@@ -320,8 +327,9 @@ StateName(EventType, EventContent, Data) ->
<c>gen_statem(3)</c>
</seealso>
manual page.
- You can, for example, reply to many callers
- and generate multiple next events to handle.
+ You can, for example, reply to many callers,
+ generate multiple next events,
+ and set time-outs to relative or absolute times.
</p>
</section>
@@ -369,6 +377,14 @@ StateName(EventType, EventContent, Data) ->
</seealso>
state timer timing out.
</item>
+ <tag><c>{timeout,Name}</c></tag>
+ <item>
+ Generated by state transition action
+ <seealso marker="stdlib:gen_statem#type-generic_timeout">
+ <c>{{timeout,Name},Time,EventContent}</c>
+ </seealso>
+ generic timer timing out.
+ </item>
<tag><c>timeout</c></tag>
<item>
Generated by state transition action
@@ -450,7 +466,7 @@ locked(
[Digit] ->
do_unlock(),
{next_state, open, Data#{remaining := Code},
- [{state_timeout,10000,lock}];
+ [{state_timeout,10000,lock}]};
[Digit|Rest] -> % Incomplete
{next_state, locked, Data#{remaining := Rest}};
_Wrong ->
@@ -779,7 +795,7 @@ handle_event(cast, {button,Digit}, State, #{code := Code} = Data) ->
[Digit] -> % Complete
do_unlock(),
{next_state, open, Data#{remaining := Code},
- [{state_timeout,10000,lock}};
+ [{state_timeout,10000,lock}]};
[Digit|Rest] -> % Incomplete
{keep_state, Data#{remaining := Rest}};
[_|_] -> % Wrong
@@ -873,7 +889,7 @@ stop() ->
<marker id="Event Time-Outs" />
<title>Event Time-Outs</title>
<p>
- A timeout feature inherited from <c>gen_statem</c>'s predecessor
+ A time-out feature inherited from <c>gen_statem</c>'s predecessor
<seealso marker="stdlib:gen_fsm"><c>gen_fsm</c></seealso>,
is an event time-out, that is,
if an event arrives the timer is cancelled.
@@ -906,24 +922,24 @@ locked(
...
]]></code>
<p>
- Whenever we receive a button event we start an event timeout
+ Whenever we receive a button event we start an event time-out
of 30 seconds, and if we get an event type <c>timeout</c>
we reset the remaining code sequence.
</p>
<p>
- An event timeout is cancelled by any other event so you either
- get some other event or the timeout event. It is therefore
- not possible nor needed to cancel or restart an event timeout.
+ An event time-out is cancelled by any other event so you either
+ get some other event or the time-out event. It is therefore
+ not possible nor needed to cancel or restart an event time-out.
Whatever event you act on has already cancelled
- the event timeout...
+ the event time-out...
</p>
</section>
<!-- =================================================================== -->
<section>
- <marker id="Erlang Timers" />
- <title>Erlang Timers</title>
+ <marker id="Generic Time-Outs" />
+ <title>Generic Time-Outs</title>
<p>
The previous example of state time-outs only work if
the state machine stays in the same state during the
@@ -934,13 +950,68 @@ locked(
You may want to start a timer in one state and respond
to the time-out in another, maybe cancel the time-out
without changing states, or perhaps run multiple
- time-outs in parallel. All this can be accomplished
- with Erlang Timers:
+ time-outs in parallel. All this can be accomplished with
+ <seealso marker="stdlib:gen_statem#type-generic_timeout">generic time-outs</seealso>.
+ They may look a little bit like
+ <seealso marker="stdlib:gen_statem#type-event_timeout">event time-outs</seealso>
+ but contain a name to allow for any number of them simultaneously
+ and they are not automatically cancelled.
+ </p>
+ <p>
+ Here is how to accomplish the state time-out
+ in the previous example by instead using a generic time-out
+ named <c>open_tm</c>:
+ </p>
+ <code type="erl"><![CDATA[
+...
+locked(
+ cast, {button,Digit},
+ #{code := Code, remaining := Remaining} = Data) ->
+ case Remaining of
+ [Digit] ->
+ do_unlock(),
+ {next_state, open, Data#{remaining := Code},
+ [{{timeout,open_tm},10000,lock}]};
+...
+
+open({timeout,open_tm}, lock, Data) ->
+ do_lock(),
+ {next_state,locked,Data};
+open(cast, {button,_}, Data) ->
+ {keep_state,Data};
+...
+ ]]></code>
+ <p>
+ Just as
+ <seealso marker="#State Time-Outs">state time-outs</seealso>
+ you can restart or cancel a specific generic time-out
+ by setting it to a new time or <c>infinity</c>.
+ </p>
+ <p>
+ Another way to handle a late time-out can be to not cancel it,
+ but to ignore it if it arrives in a state
+ where it is known to be late.
+ </p>
+ </section>
+
+<!-- =================================================================== -->
+
+ <section>
+ <marker id="Erlang Timers" />
+ <title>Erlang Timers</title>
+ <p>
+ The most versatile way to handle time-outs is to use
+ Erlang Timers; see
<seealso marker="erts:erlang#start_timer/4"><c>erlang:start_timer3,4</c></seealso>.
+ Most time-out tasks can be performed with the
+ time-out features in <c>gen_statem</c>,
+ but an example of one that can not is if you should need
+ the return value from
+ <seealso marker="erts:erlang#cancel_timer/2"><c>erlang:cancel_timer(Tref)</c></seealso>, that is; the remaining time of the timer.
</p>
<p>
Here is how to accomplish the state time-out
- in the previous example by insted using an Erlang Timer:
+ in the previous example by instead using an Erlang Timer:
</p>
<code type="erl"><![CDATA[
...
@@ -1596,7 +1667,7 @@ handle_event(
{call,From}, code_length,
{_StateName,_LockButton}, #{code := Code}) ->
{keep_state_and_data,
- [{reply,From,length(Code)}]};
+ [{reply,From,length(Code)}]};
%%
%% State: locked
handle_event(
@@ -1636,7 +1707,7 @@ handle_event(
if
Digit =:= LockButton ->
{next_state, {locked,LockButton}, Data,
- [{reply,From,locked}]);
+ [{reply,From,locked}]};
true ->
{keep_state_and_data,
[postpone]}
@@ -1710,10 +1781,10 @@ handle_event(
EventType, EventContent,
{open,LockButton}, Data) ->
case {EventType, EventContent} of
- {enter, _OldState} ->
- do_unlock(),
- {keep_state_and_data,
- [{state_timeout,10000,lock},hibernate]};
+ {enter, _OldState} ->
+ do_unlock(),
+ {keep_state_and_data,
+ [{state_timeout,10000,lock},hibernate]};
...
]]></code>
<p>