Several FairMQ fixes and improvements:

- FairMQ: add possibility to poll on multiple channels.
- FairMQ: include command channel when polling on blocking calls (for unblocking without termination).
- FairMQ: move signal handler inside of FairMQDevice class (call FairMQDevice::CatchSignals() in the main function).
- FairMQ: add 'bool CheckCurrentState(statename)' (instead of 'GetCurrentState() == statename' that cannot be thread safe).
- FairMQDevice: add 'InteractiveStateLoop()' method that can be used to change states from the command line.
- FairMQDevice: add automatic transition to IDLE state if Run() exits without an external event.
- FairMQDevice: implement device reset.
- FairMQDevice: use unordered_map for device channels.
- FairMQChannel: improve address validation for channels.
- FairMQChannel: add ExpectsAnotherPart() method to check if another msg part is expected (old approach still works).
- FairMQ: remove invalid transition from the run files.
- FairMQFileSink: disable ROOT termination signal handler.
- Tutorial3: spawn xterm windows from start scripts without overlapping for better visibility.
- FairMQ Examples: update protobuf test and move its files to a common directory.
- FairMQStateMachine: improve feedback on invalid transitions (more readable).

fairmq/devices/FairMQBenchmarkSampler.cxx

@@ -40,12 +40,15 @@ void FairMQBenchmarkSampler::Run()
     void* buffer = operator new[](fEventSize);
     FairMQMessage* baseMsg = fTransportFactory->CreateMessage(buffer, fEventSize);
 
-    while (GetCurrentState() == RUNNING)
+    // store the channel reference to avoid traversing the map on every loop iteration
+    const FairMQChannel& dataChannel = fChannels.at("data-out").at(0);
+
+    while (CheckCurrentState(RUNNING))
     {
         FairMQMessage* msg = fTransportFactory->CreateMessage();
         msg->Copy(baseMsg);
 
-        fChannels["data-out"].at(0).Send(msg);
+        dataChannel.Send(msg);
 
         --fEventCounter;
 
@@ -69,7 +72,7 @@ void FairMQBenchmarkSampler::Run()
 
 void FairMQBenchmarkSampler::ResetEventCounter()
 {
-    while (GetCurrentState() == RUNNING)
+    while (CheckCurrentState(RUNNING))
     {
         try
         {