o2sim: Fixing a problem when generated event is empty

sawenzel · sawenzel · commit a54fbb7762a0 · 2019-01-11T16:27:41.000+01:00
We encountered infinite loops when the event was empty (or at least
when there is no real trackable particle inside).
This commit is fixing this problem.
diff --git a/run/O2PrimaryServerDevice.h b/run/O2PrimaryServerDevice.h
@@ -159,6 +159,8 @@ class O2PrimaryServerDevice : public FairMQDevice
 
     auto& prims = mStack.getPrimaries();
     auto numberofparts = (int)std::ceil(prims.size() / (1. * mChunkGranularity));
+    // number of parts should be at least 1 (even if empty)
+    numberofparts = std::max(1, numberofparts);
 
     o2::Data::PrimaryChunk m;
     o2::Data::SubEventInfo i;
