From 271ea4bc7527bb255a268cf4a2868d2421b2c5a9 Mon Sep 17 00:00:00 2001
From: Raj Bhattacharjea <raj.b@gatech.edu>
Date: Thu, 10 Apr 2008 15:04:47 -0400
Subject: [PATCH] Add support for TCP cwnd tracing

---
 src/core/config.cc              |  2 +-
 src/core/traced-value.h         |  6 ++++++
 src/internet-node/tcp-socket.cc | 19 +++++++++++++++++--
 src/internet-node/tcp-socket.h  | 15 +++++++++------
 4 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/src/core/config.cc b/src/core/config.cc
index cd47003e8..409d05557 100644
--- a/src/core/config.cc
+++ b/src/core/config.cc
@@ -190,7 +190,7 @@ Resolver::DoResolve (std::string path, Ptr<Object> root)
     {
       // This is a call to GetObject
       std::string tidString = item.substr (1, item.size () - 1);
-      NS_LOG_DEBUG ("GetObject="<<tidString<<"on path="<<GetResolvedPath (""));
+      NS_LOG_DEBUG ("GetObject="<<tidString<<" on path="<<GetResolvedPath (""));
       TypeId tid = TypeId::LookupByName (tidString);
       Ptr<Object> object = root->GetObject<Object> (tid);
       if (object == 0)
diff --git a/src/core/traced-value.h b/src/core/traced-value.h
index 6210d42b1..1e45aeaec 100644
--- a/src/core/traced-value.h
+++ b/src/core/traced-value.h
@@ -118,6 +118,12 @@ private:
   TracedCallback<T,T> m_cb;
 };
 
+template <typename T>
+std::ostream& operator << (std::ostream& os, const TracedValue<T>& rhs)
+{
+  return os<<rhs.Get();
+}
+
 template <typename T, typename U>
 bool operator == (const TracedValue<T> &lhs, const TracedValue<U> &rhs)
 {
diff --git a/src/internet-node/tcp-socket.cc b/src/internet-node/tcp-socket.cc
index 40a511444..58495f5bf 100644
--- a/src/internet-node/tcp-socket.cc
+++ b/src/internet-node/tcp-socket.cc
@@ -31,6 +31,7 @@
 #include "tcp-typedefs.h"
 #include "ns3/simulator.h"
 #include "ns3/packet.h"
+#include "ns3/trace-source-accessor.h"
 
 #include <algorithm>
 
@@ -40,6 +41,20 @@ using namespace std;
 
 namespace ns3 {
 
+NS_OBJECT_ENSURE_REGISTERED (TcpSocket);
+
+TypeId
+TcpSocket::GetTypeId ()
+{
+  static TypeId tid = TypeId("ns3::TcpSocket")
+    .SetParent<Socket> ()
+    .AddTraceSource ("CongestionWindow",
+                     "The TCP connection's congestion window",
+                     MakeTraceSourceAccessor (&TcpSocket::m_cWnd))
+    ;
+  return tid;
+}
+
   TcpSocket::TcpSocket ()
   : m_skipRetxResched (false),
     m_dupAckCount (0),
@@ -899,7 +914,7 @@ uint32_t  TcpSocket::Window ()
 {
   NS_LOG_FUNCTION;
   NS_LOG_LOGIC ("TcpSocket::Window() "<<this);
-  return std::min (m_rxWindowSize, m_cWnd);
+  return std::min (m_rxWindowSize, m_cWnd.Get());
 }
 
 uint32_t  TcpSocket::AvailableWindow ()
@@ -1120,7 +1135,7 @@ void TcpSocket::NewAck (SequenceNumber seq)
     }
   else
     { // Congestion avoidance mode, adjust by (ackBytes*segSize) / cWnd
-      double adder =  ((double) m_segmentSize * m_segmentSize) / m_cWnd;
+      double adder =  ((double) m_segmentSize * m_segmentSize) / m_cWnd.Get();
       if (adder < 1.0) 
         {
           adder = 1.0;
diff --git a/src/internet-node/tcp-socket.h b/src/internet-node/tcp-socket.h
index 95f7ad570..7499e2a3e 100644
--- a/src/internet-node/tcp-socket.h
+++ b/src/internet-node/tcp-socket.h
@@ -22,6 +22,7 @@
 
 #include <stdint.h>
 #include "ns3/callback.h"
+#include "ns3/traced-value.h"
 #include "ns3/socket.h"
 #include "ns3/ptr.h"
 #include "ns3/ipv4-address.h"
@@ -31,6 +32,7 @@
 #include "sequence-number.h"
 #include "rtt-estimator.h"
 
+
 namespace ns3 {
 
 class Ipv4EndPoint;
@@ -42,6 +44,7 @@ class TcpHeader;
 class TcpSocket : public Socket
 {
 public:
+  static TypeId GetTypeId (void);
   /**
    * Create an unbound tcp socket.
    */
@@ -152,12 +155,12 @@ private:
   SequenceNumber m_firstPendingSequence;
 
   // Window management
-  uint32_t          m_segmentSize;                     // SegmentSize
-  uint32_t          m_rxWindowSize;
-  uint32_t          m_advertisedWindowSize;            // Window to advertise to peer
-  uint32_t          m_cWnd;            // Congestion window
-  uint32_t          m_ssThresh;                     // Slow Start Threshold
-  uint32_t          m_initialCWnd;     // Initial (and reset) value for cWnd
+  uint32_t                       m_segmentSize;          //SegmentSize
+  uint32_t                       m_rxWindowSize;
+  uint32_t                       m_advertisedWindowSize; //Window to advertise
+  TracedValue<uint32_t>          m_cWnd;                 //Congestion window
+  uint32_t                       m_ssThresh;             //Slow Start Threshold
+  uint32_t                       m_initialCWnd;          //Initial cWnd value
 
   // Round trip time estimation
   Ptr<RttEstimator> m_rtt;