Update README and add contrib dir

contrib/tsn/model/frer-sequence-generation-function.cc

@@ -0,0 +1,70 @@
+#include "frer-sequence-generation-function.h"
+
+#include "ns3/log.h"
+#include "ns3/boolean.h"
+
+namespace ns3
+{
+
+NS_LOG_COMPONENT_DEFINE("SequenceGenerationFunction");
+
+NS_OBJECT_ENSURE_REGISTERED(SequenceGenerationFunction);
+
+TypeId
+SequenceGenerationFunction::GetTypeId()
+{
+    static TypeId tid =
+        TypeId("ns3::SequenceGenerationFunction")
+            .SetParent<Object>()
+            .SetGroupName("tsn")
+            .AddConstructor<SequenceGenerationFunction>()
+            .AddAttribute("Direction",
+                          "A Boolean indicating whether the Sequence generation function is to be placed on the out-facing (True) or in-facing (False)",
+                          BooleanValue(false),
+                          MakeBooleanAccessor(&SequenceGenerationFunction::m_frerSeqGenDirection),
+                          MakeBooleanChecker());
+    return tid;
+}
+
+
+SequenceGenerationFunction::SequenceGenerationFunction()
+{
+    NS_LOG_FUNCTION(this);
+}
+
+SequenceGenerationFunction::~SequenceGenerationFunction()
+{
+    NS_LOG_FUNCTION(this);
+}
+
+void
+SequenceGenerationFunction::SetStreamHandle(std::vector<uint32_t> frerSeqGenStreamList)
+{
+  NS_LOG_FUNCTION(this);
+  m_frerSeqGenStreamList = frerSeqGenStreamList;
+}
+
+bool
+SequenceGenerationFunction::IsApplicable(uint32_t streamHandle)
+{
+  NS_LOG_FUNCTION(this);
+  for (uint32_t i = 0; i < m_frerSeqGenStreamList.size(); i++)
+  {
+    if(m_frerSeqGenStreamList[i]==streamHandle)
+    {
+      return true;
+    }
+  }
+  return false;
+}
+
+uint16_t
+SequenceGenerationFunction::GetSequenceNumber()
+{
+  NS_LOG_FUNCTION(this);
+  uint16_t genSeqNum = m_GenSeqNum;
+  m_GenSeqNum++;
+  return genSeqNum;
+}
+
+}