also track sequence number for syncronizaton

protocols/sacn/arbitratinguniverse.cpp

@@ -178,12 +178,13 @@ void ArbitratingUniverse::set(std::shared_ptr<ACN::DMP::Pdu> pdu,
 
 
 /**
- * @brief MergeProxyUniverse::synchronize
+ * @brief ArbitratingUniverse::synchronize
+ * @param sequence_number
  */
-void ArbitratingUniverse::synchronize()
+void ArbitratingUniverse::synchronize(uint8_t sequence_number)
 {
   for ( auto& [_, uni] : sources_)
-    uni->synchronize();
+    uni->synchronize(sequence_number);
 }
 
 

protocols/sacn/arbitratinguniverse.h

@@ -73,7 +73,7 @@ public:
     std::shared_ptr<DATA::data_header> provenance() const override;
     void setProvenance(std::shared_ptr<DATA::data_header>) override {};
     bool isSyncronized() const override;
-    void synchronize() override;
+    void synchronize(uint8_t = 0) override;
 
     // DMX::Universe Overrides:
     const DMX::DimmerData *data() const override;

protocols/sacn/receiver.cpp

@@ -227,15 +227,15 @@ void Receiver::dataFrameHandler(ACN::PDU::Message<DATA::Pdu> frame) {
   /// > \cite sACN 6.7.2 Sequence Numbering
   /// >
   /// > Having first received a packet with sequence number A,
-  auto a = universe->provenance()->sequence_number;
   /// > a second packet with sequence number B arrives.
-  auto b = source->sequence_number;
   /// > If, using signed 8-bit binary arithmetic, B - A
-  int8_t dif = b - a;
   /// > is less than or equal to 0, but greater than -20,
-  if (dif <= 0 && dif > -20)
   /// > then the packet containing sequence number B shall be deemed out of
   /// > sequence and discarded.
+  auto a = universe->provenance()->sequence_number;
+  auto b = source->sequence_number;
+  int8_t dif = b - a;
+  if (dif <= 0 && dif > -20)
   /// Tolerate out-of-spec sources transmitting 0s instead of a sequence number.
     if (!(a == 0 && b == 0))
       return;
@@ -269,7 +269,7 @@ void Receiver::dataFrameHandler(ACN::PDU::Message<DATA::Pdu> frame) {
 void Receiver::syncFrameHandler(ACN::PDU::Message<EXTENDED::Pdu> frame)
 {
   auto header = static_cast<EXTENDED::sync_header*>(frame->header());
-  universes_.at(header->sync_address)->synchronize();
+  universes_.at(header->sync_address)->synchronize(header->sequence_number);
 }
 
 

protocols/sacn/universe.cpp

@@ -160,15 +160,34 @@ std::shared_ptr<DATA::data_header> Universe::provenance() const
 
 /**
  * @brief Universe::synchronize
+ * @param sequence_number
  */
-void Universe::synchronize()
+void Universe::synchronize(uint8_t sequence_number)
 {
-  if (sync_data_)
-    {
-      DMX::Universe::setData(*sync_data_);
-      delete sync_data_;
-      sync_data_ = nullptr;
-    }
+  if (!sync_data_)
+    return;
+
+  /// > \cite sACN 6.7.2 Sequence Numbering
+  /// >
+  /// > Having first received a packet with sequence number A,
+  /// > a second packet with sequence number B arrives.
+  /// > If, using signed 8-bit binary arithmetic, B - A
+  /// > is less than or equal to 0, but greater than -20,
+  /// > then the packet containing sequence number B shall be deemed out of
+  /// > sequence and discarded.
+  auto a = sync_sequence_;
+  auto b = sequence_number;
+  int8_t dif = b - a;
+  if (dif <= 0 && dif > -20)
+  /// Tolerate out-of-spec sources transmitting 0s instead of a sequence number.
+    if (!(a == 0 && b == 0))
+      return;
+  sync_sequence_ = sequence_number;
+
+  DMX::Universe::setData(*sync_data_);
+
+  delete sync_data_;
+  sync_data_ = nullptr;
 }
 
 };  // namespace SACN

protocols/sacn/universe.h

@@ -52,7 +52,7 @@ public:
   virtual void setProvenance(std::shared_ptr<DATA::data_header>);
 
   virtual bool isSyncronized() const;
-  virtual void synchronize();
+  virtual void synchronize(uint8_t = 0);
 
 protected:
   /**
@@ -71,6 +71,7 @@ protected:
 private:
   std::shared_ptr<DATA::data_header> provenance_;
   std::vector<uint8_t> * sync_data_ = nullptr;
+  uint8_t sync_sequence_ = 0;
 };
 
 } // SACN namespace