-- Jan Willamowius, Founder of the GNU Gatekeeper Project EMail : jan@willamowius.de Website: http://www.gnugk.org Support: http://www.willamowius.com/gnugk-support.html Relaxed Communications GmbH Frahmredder 91 22393 Hamburg Geschäftsführer: Jan Willamowius HRB 125261 (Amtsgericht Hamburg) USt-IdNr: DE286003584 Iurii Gordiienko wrote: > Hi Jan, > I think, your solution will work, but in my opinion we have to fix  H323Connection::SendSignalSetup function, because it (only) has strange behavior. It has different internal state (locked and unlocked) for the same return reason (Not H323Connection::EndedByCallerAbort). > Take a look to my proposition (a bit draft variant but in anyway) - in worst case (if not able to Lock the mutexes) we only lost the real reason (why does it fails) and return EndedByCallerAbort. > H323Connection::SendSignalSetup > {       CallEndReason reason = NumCallEndReasons; > > > //... >       // Do the transport connect       connectionState = AwaitingTransportConnect; >       // Release the mutex as can deadlock trying to clear call during connect.       Unlock(); >       PBoolean connectFailed = false;       if (!signallingChannel->IsOpen()) {         signallingChannel->SetWriteTimeout(100);         connectFailed = !signallingChannel->Connect();       } >       // See if transport connect failed, abort if so.       if (connectFailed) {         connectionState = NoConnectionActive;         switch (signallingChannel->GetErrorNumber()) {           case ENETUNREACH :             reason = EndedByUnreachable;             break;           case ECONNREFUSED :             reason = EndedByNoEndPoint;             break;           case ETIMEDOUT :             reason =  EndedByHostOffline;             break;           default:              reason = EndedByConnectFail;         }       } >   }  >   // Lock while checking for shutting down.   if (!Lock())     return EndedByCallerAbort;   else if(NumCallEndReasons != reason)     return reason; > //... >     return reason; } > Thanks -- Iurii Gordiienko > > --- Original message --- > From: "Jan Willamowius" jan@willamowius.de > Date: 27 December 2015, 19:47:21 > > Hi Iurii, > > PTLib 2.10.x and 2.11.x have a method to check, if a mutex is already > locked, but they changed the API and from 2.12.x on there is no way to > check except to try to lock it. > > Replace H323Connection::Unlock() in src/h323.cxx with this version: > > void H323Connection::Unlock() > { > // calling Signal() on a mutex that isn't locked is causing an assert, > // so we make sure it is locked before the Signal() > innerMutex.Wait(0); > innerMutex.Signal(); > outerMutex.Wait(0); > outerMutex.Signal(); > } > > Please try the change and report back how it works. > Then I'll commit the code to the CVS. > > Regards, > Jan > > -- > Jan Willamowius, Founder of the GNU Gatekeeper Project > EMail : jan@willamowius.de > Website: http://www.gnugk.org > Support: http://www.willamowius.com/gnugk-support.html > > Relaxed Communications GmbH > Frahmredder 91 > 22393 Hamburg > Geschäftsführer: Jan Willamowius > HRB 125261 (Amtsgericht Hamburg) > USt-IdNr: DE286003584 > > > Iurii Gordiienko wrote: > > Hi, > > I have found a bug with twice H323Connection::Unlock() call if we have an connection issue. > > Take a look: > > 1.We are running connection.SendSignalSetup function from H225CallThread::Main() and if it returns any reason!=H323Connection::EndedByCallerAbort we will Unlock the connection. > > > > void H225CallThread::Main() {   PTRACE(3, "H225\tStarted call thread"); > >   if (connection.Lock()) {     H323Connection::CallEndReason reason = connection.SendSignalSetup(alias, address); > >     // Special case, if we aborted the call then already will be unlocked     if (reason != H323Connection::EndedByCallerAbort)       connection.Unlock(); > >     // bla-bla-bla } > > > > 2.But we have case when connection.SendSignalSetup returns non H323Connection::EndedByCallerAbort reason but has own unlocked state - for this case PTLIB will unlock the mutex twice with assert (as minimum) message. > > H323Connection::SendSignalSetup(const PString & alias, > >                                                               const H323TransportAddress & address) { //bla-bla-bla > >       // Release the mutex as can deadlock trying to clear call during connect.       Unlock(); > >       PBoolean connectFailed = false;       if (!signallingChannel->IsOpen()) {         signallingChannel->SetWriteTimeout(100);         connectFailed = !signallingChannel->Connect();       } > >       // See if transport connect failed, abort if so.       if (connectFailed) {         connectionState = NoConnectionActive;         switch (signallingChannel->GetErrorNumber()) {           case ENETUNREACH :             return EndedByUnreachable;           case ECONNREFUSED :             return EndedByNoEndPoint;           case ETIMEDOUT :             return EndedByHostOffline;         }         return EndedByConnectFail;       } > > } > > Thanks -- Iurii Gordiienko >