[Bug 1055] State machine signalling on an operation causes multiple transitions

http://bugs.orocos.org/show_bug.cgi?id=1055

--- Comment #2 from Peter Soetens <[email protected]> 2014-03-13 17:02:27 CET ---
(In reply to comment #1)
> (In reply to comment #0)
> > Created attachment 868 [details] [details]
> > Expands state machine unit test
> > 
> > Emitting v_event() in the following, while in STATE1, causes a transition to
> > FINI. So v_event() has been taken in both STATE1 and STATE2, even though only
> > one signal occurred.
> > 
> >     string prog = string("StateMachine X {\n")
> >     + " initial state INIT {\n"
> >     + "    transitions { select STATE1 }\n"
> >     + " }\n"
> >     + " state STATE1 {\n"
> >     + "    transition v_event() select STATE2\n" // test signal transition
> >     + " }\n"
> >     + " state STATE2 {\n"
> >     + "    transition v_event() select FINI\n"   // test signal transition
> >     + " }\n"
> >     + " final state FINI {} \n"
> >     + "}\n"
> >     + "RootMachine X x()\n";
> > 
> > Patch containing failing unit test attached.
> > 
> > Linking CXX executable state_test
> > Running 16 test cases...
> > ~/orocos_ws/src/orocos_toolchain/rtt/tests/state_test.cpp(822): error in
> > "testStateOperationSignalTransition2": check "STATE2" ==
> > sm->getCurrentStateName() failed [STATE2 != FINI]
> > ~/orocos_ws/src/orocos_toolchain/rtt/tests/state_test.cpp(826): error in
> > "testStateOperationSignalTransition2": check "STATE2" ==
> > sm->getCurrentStateName() failed [STATE2 != FINI]
> > 
> > Demonstrated in Linux Mint 15.
> 
> Thanks for the unit test, I'm looking into it.

I have reproduced it and figured out why it is happening. Both event handlers
are installed in the operation and emit'ed when the operation is called. The
first event handler causes a transition which happens immediately (OwnThread!)
and the next transition happens then as well because the state changed to the
correct state.

We'll have to think of a way to prevent the second transition in the second
event handler. The operation needs to call all call-backs since it can't know
if it's all for the same state machine or different state machines etc.

Peter

-- 
Configure bugmail: http://bugs.orocos.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.
You are the assignee for the bug.
-- 
Orocos-Dev mailing list
[email protected]
http://lists.mech.kuleuven.be/mailman/listinfo/orocos-dev