[certi-dev] A crash in CERTI when used in multithread application

[WQY]

Hi,

 

I am using CERTI to develop GUI applications. In the common situation, I used two threads: the main thread used for UI, the other called RTIambassador::tick() repeatedly to process FederateAmbassador callbacks.

My question is when I use RTIambassador to send interactions, (of course this happens in UI main thread), my application crashed sometimes. I found the problem is this:

 

RTIambPrivateRefs.cc, in function executeService():

       req->send(socketUn,msgBufSend);

       …

       rep->receive(socketUn,msgBufReceive);

       …

       if (rep->getMessageType() != req->getMessageType())

              throw RTI::RTIinternalError("RTIambPrivateRefs::executeService: rep->type != req->type");

So, this requires that: req and rep must have the save type, or an exception will be arised.

 

However, in RTIambassador.cc, function __tick_kernel:

       vers_RTI.send(privateRefs->socketUn,privateRefs->msgBufSend);

       …

       while (1)

       {

              vers_Fed.reset(M_Factory::receive(privateRefs->socketUn));

              …

              if (vers_Fed->getMessageType() == Message::TICK_REQUEST)

              …

              return RTI::Boolean(static_cast<M_Tick_Request*>(vers_Fed.get())->getMultiple());

              …

              // Otherwise, the RTI calls a FederateAmbassador service.

              privateRefs->callFederateAmbassador(vers_Fed.get());

              …

}

So, here is the question: the tick() thread receives other message, and cause the main thread’s req and rep have different type, and the crash happens.

 

Did I use CERTI in a wrong way, or I make some mistake?

 

Please help!

 

Thanks!

James