utils: Adding some NDN network-layer rate tracers
diff --git a/utils/tracers/ndn-l3-tracer.h b/utils/tracers/ndn-l3-tracer.h
new file mode 100644
index 0000000..74c0ef9
--- /dev/null
+++ b/utils/tracers/ndn-l3-tracer.h
@@ -0,0 +1,135 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2011-2012 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author:  Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#ifndef CCNX_L3_TRACER_H
+#define CCNX_L3_TRACER_H
+
+#include "ns3/ptr.h"
+#include "ns3/simple-ref-count.h"
+
+namespace ns3 {
+
+class Node;
+class Packet;
+
+namespace ndn {
+
+class InterestHeader;
+class Face;
+class ContentObjectHeader;
+
+class L3Tracer : public SimpleRefCount<L3Tracer>
+{
+public:
+  L3Tracer (Ptr<Node> node);
+  L3Tracer (const std::string &node);
+  virtual ~L3Tracer ();
+
+  void
+  Connect ();
+  
+  virtual void
+  PrintHeader (std::ostream &os) const = 0;
+
+  virtual void
+  Print (std::ostream &os) const = 0;
+  
+  virtual void
+  OutInterests  (std::string context,
+                 Ptr<const InterestHeader>, Ptr<const Face>) = 0;
+
+  virtual void
+  InInterests   (std::string context,
+                 Ptr<const InterestHeader>, Ptr<const Face>) = 0;
+
+  virtual void
+  DropInterests (std::string context,
+                 Ptr<const InterestHeader>, Ptr<const Face>) = 0;
+  
+  virtual void
+  OutNacks  (std::string context,
+             Ptr<const InterestHeader>, Ptr<const Face>) = 0;
+
+  virtual void
+  InNacks   (std::string context,
+             Ptr<const InterestHeader>, Ptr<const Face>) = 0;
+
+  virtual void
+  DropNacks (std::string context,
+             Ptr<const InterestHeader>, Ptr<const Face>) = 0;
+
+  
+  virtual void
+  OutData  (std::string context,
+            Ptr<const ContentObjectHeader>, Ptr<const Packet>, bool fromCache, Ptr<const Face>) = 0;
+
+  virtual void
+  InData   (std::string context,
+            Ptr<const ContentObjectHeader>, Ptr<const Packet>, Ptr<const Face>) = 0;
+
+  virtual void
+  DropData (std::string context,
+            Ptr<const ContentObjectHeader>, Ptr<const Packet>, Ptr<const Face>) = 0;
+
+protected:
+  std::string m_node;
+  Ptr<Node> m_nodePtr;
+
+  struct Stats
+  {
+    inline void Reset ()
+    {
+      m_inInterests   = 0;
+      m_outInterests  = 0;
+      m_dropInterests = 0;
+      m_inNacks       = 0;
+      m_outNacks      = 0;
+      m_dropNacks     = 0;
+      m_inData        = 0;
+      m_outData       = 0;
+      m_dropData      = 0;
+    }
+    
+    double m_inInterests;
+    double m_outInterests;
+    double m_dropInterests;
+    double m_inNacks;
+    double m_outNacks;
+    double m_dropNacks;
+    double m_inData;
+    double m_outData;
+    double m_dropData;
+  };
+};
+
+inline std::ostream&
+operator << (std::ostream &os, const L3Tracer &tracer)
+{
+  os << "# ";
+  tracer.PrintHeader (os);
+  os << "\n";
+  tracer.Print (os);
+  return os;
+}
+
+} // namespace ndn
+} // namespace ns3
+
+#endif // CCNX_L3_TRACER_H