Making lossy tests deterministic [5073] (#481)

* Refs #5073. Making package drop deterministic.

* Refs #5073. Removing unused test_RTCPMessageManager.

include/fastrtps/transport/TCPTransportInterface.h

@@ -180,7 +180,6 @@ class TCPTransportInterface : public TransportInterface
 
 public:
     friend class RTCPMessageManager;
-    friend class test_RTCPMessageManager;
 
     virtual ~TCPTransportInterface();
 

include/fastrtps/transport/test_UDPv4Transport.h

@@ -48,19 +48,33 @@ class test_UDPv4Transport : public UDPv4Transport
     RTPS_DllAPI static uint32_t test_UDPv4Transport_DropLogLength;
 
 private:
-    uint8_t drop_data_messages_percentage_;
+
+    struct PercentageData
+    {
+        PercentageData(uint8_t percent)
+            : percentage(percent)
+            , accumulator(0)
+        {
+        }
+
+        uint8_t percentage;
+        uint8_t accumulator;
+    };
+
+    PercentageData drop_data_messages_percentage_;
     bool drop_participant_builtin_topic_data_;
     bool drop_publication_builtin_topic_data_;
     bool drop_subscription_builtin_topic_data_;
-    uint8_t drop_data_frag_messages_percentage_;
-    uint8_t drop_heartbeat_messages_percentage_;
-    uint8_t drop_ack_nack_messages_percentage_;
+    PercentageData drop_data_frag_messages_percentage_;
+    PercentageData drop_heartbeat_messages_percentage_;
+    PercentageData drop_ack_nack_messages_percentage_;
     std::vector<SequenceNumber_t> sequence_number_data_messages_to_drop_;
-    uint8_t percentage_of_messages_to_drop_;
+    PercentageData percentage_of_messages_to_drop_;
 
     bool log_drop(const octet* buffer, uint32_t size);
     bool packet_should_drop(const octet* send_buffer, uint32_t send_buffer_size);
     bool random_chance_drop();
+    bool should_be_dropped(PercentageData* percentage);
 };
 
 } // namespace rtps

src/cpp/CMakeLists.txt

@@ -88,7 +88,6 @@ set(${PROJECT_NAME}_source_files
     transport/tcp/TCPControlMessage.cpp
     transport/tcp/RTCPMessageManager.cpp
     transport/timedevent/TCPKeepAliveEvent.cpp
-    #transport/tcp/test_RTCPMessageManager.cpp
 
     types/AnnotationDescriptor.cpp
     types/AnnotationParameterValue.cpp

src/cpp/transport/test_UDPv4Transport.cpp

@@ -42,7 +42,6 @@ test_UDPv4Transport::test_UDPv4Transport(const test_UDPv4TransportDescriptor& de
         UDPv4Transport::mReceiveBufferSize = descriptor.receiveBufferSize;
         test_UDPv4Transport_DropLog.clear();
         test_UDPv4Transport_DropLogLength = descriptor.dropLogLength;
-        srand(static_cast<unsigned>(time(NULL)));
     }
 
 test_UDPv4TransportDescriptor::test_UDPv4TransportDescriptor():
@@ -161,13 +160,13 @@ bool test_UDPv4Transport::packet_should_drop(const octet* send_buffer, uint32_t
                         (!drop_subscription_builtin_topic_data_ && writer_id == c_EntityId_SEDPSubWriter))
                     return false;
 
-                if(drop_data_messages_percentage_ > (rand()%100))
+                if(should_be_dropped(&drop_data_messages_percentage_))
                     return true;
 
                 break;
 
             case ACKNACK:
-                if(drop_ack_nack_messages_percentage_ > (rand()%100))
+                if(should_be_dropped(&drop_ack_nack_messages_percentage_))
                     return true;
 
                 break;
@@ -177,13 +176,13 @@ bool test_UDPv4Transport::packet_should_drop(const octet* send_buffer, uint32_t
                 CDRMessage::readInt32(&cdrMessage, &sequence_number.high);
                 CDRMessage::readUInt32(&cdrMessage, &sequence_number.low);
                 cdrMessage.pos = old_pos;
-                if(drop_heartbeat_messages_percentage_ > (rand()%100))
+                if(should_be_dropped(&drop_heartbeat_messages_percentage_))
                     return true;
 
                 break;
 
             case DATA_FRAG:
-                if(drop_data_frag_messages_percentage_  > (rand()%100))
+                if(should_be_dropped(&drop_data_frag_messages_percentage_))
                     return true;
 
                 break;
@@ -227,7 +226,19 @@ bool test_UDPv4Transport::log_drop(const octet* buffer, uint32_t size)
 
 bool test_UDPv4Transport::random_chance_drop()
 {
-    return percentage_of_messages_to_drop_ > (rand()%100);
+    return should_be_dropped(&percentage_of_messages_to_drop_);
+}
+
+bool test_UDPv4Transport::should_be_dropped(PercentageData* percent)
+{
+    percent->accumulator += percent->percentage;
+    if (percent->accumulator >= 100u)
+    {
+        percent->accumulator -= 100u;
+        return true;
+    }
+
+    return false;
 }
 
 } // namespace rtps