Tracing window size in CcnxConsumerWindow
diff --git a/helper/tracers/ccnx-consumer-window-tracer.h b/helper/tracers/ccnx-consumer-window-tracer.h
new file mode 100644
index 0000000..b178ee1
--- /dev/null
+++ b/helper/tracers/ccnx-consumer-window-tracer.h
@@ -0,0 +1,69 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2012 UCLA
+ *
+ * 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_CONSUMER_WINDOW_TRACER_H
+#define CCNX_CONSUMER_WINDOW_TRACER_H
+
+#include "ns3/ptr.h"
+#include "ns3/simple-ref-count.h"
+
+namespace ns3 {
+
+class Node;
+
+class CcnxConsumerWindowTracer : public SimpleRefCount<CcnxConsumerWindowTracer>
+{
+public:
+  CcnxConsumerWindowTracer (std::ostream &os, Ptr<Node> node, const std::string &appId = "*");
+  virtual ~CcnxConsumerWindowTracer ()  { };
+
+  void
+  Connect ();
+
+  virtual void
+  PrintHeader (std::ostream &os) const;
+  
+  virtual void
+  Print (std::ostream &os) const;
+
+  virtual void
+  OnWindowChange (std::string context,
+                  uint32_t oldValue, uint32_t newValue);
+
+protected:
+  std::string m_appId;
+  std::string m_node;
+  Ptr<Node> m_nodePtr;
+  std::ostream& m_os;
+};
+
+inline std::ostream&
+operator << (std::ostream &os, const CcnxConsumerWindowTracer &tracer)
+{
+  os << "# ";
+  tracer.PrintHeader (os);
+  os << "\n";
+  tracer.Print (os);
+  return os;
+}
+
+} // namespace ns3
+
+#endif // CCNX_CONSUMER_WINDOW_TRACER_H