Add a socket callback that can unblock a blocked close

examples/tcp-large-transfer.cc

@@ -165,7 +165,7 @@ int main (int argc, char *argv[])
   //
   ///////////////////////////////////////////////////////////////////////////
 
-  int nBytes = 2000000;
+  int nBytes = 2000;
   uint16_t servPort = 50000;
 
   // Create a packet sink to receive these packets

src/internet-node/tcp-socket.cc

@@ -282,13 +282,25 @@ TcpSocket::ShutdownSend (void)
 {
   NS_LOG_FUNCTION_NOARGS ();
   m_shutdownSend = true;
+  if (m_state == CLOSED) 
+    {
+      return -1;
+    }
+  if (m_pendingData && m_pendingData->Size() != 0)
+    { // App shutdown with pending data must wait until all data transmitted
+      m_closeOnEmpty = true;
+      NS_LOG_LOGIC("TcpSocket "<<this<< " deferring close, state " << m_state);
+      return 0;
+    }
+  Actions_t action  = ProcessEvent (APP_CLOSE);
+  ProcessAction (action);
   return 0;
 }
 int 
 TcpSocket::ShutdownRecv (void)
 {
   NS_LOG_FUNCTION_NOARGS ();
-  m_shutdownRecv = false;
+  m_shutdownRecv = true;
   return 0;
 }
 
@@ -303,7 +315,7 @@ TcpSocket::Close (void)
   if (m_pendingData && m_pendingData->Size() != 0)
     { // App close with pending data must wait until all data transmitted
       m_closeOnEmpty = true;
-      NS_LOG_LOGIC("Socket " << this << 
+      NS_LOG_LOGIC("TcpSocket " << this << 
                    " deferring close, state " << m_state);
       return 0;
     }
@@ -955,8 +967,12 @@ bool TcpSocket::SendPendingData (bool withAck)
                          m_endPoint->GetLocalAddress (),
                          m_remoteAddress);
       m_rtt->SentSeq(m_nextTxSequence, sz);       // notify the RTT
-      // Notify the application
+      // Notify the application data was sent
       Simulator::ScheduleNow(&TcpSocket::NotifyDataSent, this, p->GetSize ());
+      if (m_state == FIN_WAIT_1)
+      {
+        Simulator::ScheduleNow(&TcpSocket::NotifyCloseUnblocks, this);
+      }
       nPacketsSent++;                             // Count sent this loop
       m_nextTxSequence += sz;                     // Advance next tx sequence
       // Note the high water mark

src/node/socket.cc

@@ -33,6 +33,13 @@ Socket::~Socket ()
   NS_LOG_FUNCTION_NOARGS ();
 }
 
+void
+Socket::SetCloseUnblocksCallback (Callback<void,Ptr<Socket> > closeUnblocks)
+{
+  NS_LOG_FUNCTION_NOARGS ();
+  m_closeUnblocks = closeUnblocks;
+}
+
 void 
 Socket::SetCloseCallback (Callback<void,Ptr<Socket> > closeCompleted)
 {
@@ -91,6 +98,15 @@ int Socket::Listen (uint32_t queueLimit)
   return 0; //XXX the base class version does nothing
 }
 
+void
+Socket::NotifyCloseUnblocks (void)
+{
+  NS_LOG_FUNCTION_NOARGS ();
+  if (!m_closeUnblocks.IsNull ())
+  {
+    m_closeUnblocks (this);
+  }
+}
 
 int Socket::Send (const uint8_t* buf, uint32_t size)
 {

src/node/socket.h

@@ -78,6 +78,8 @@ public:
    */
   virtual Ptr<Node> GetNode (void) const = 0;
 
+  void SetCloseUnblocksCallback (Callback<void, Ptr<Socket> > closeUnblocks);
+
   /**
    * \param closeCompleted Callback invoked when the close operation is
    *        completed.
@@ -316,6 +318,7 @@ public:
   virtual uint32_t GetRcvBuf (void) = 0;
 
 protected:
+  void NotifyCloseUnblocks (void);
   void NotifyCloseCompleted (void);
   void NotifyConnectionSucceeded (void);
   void NotifyConnectionFailed (void);
@@ -327,6 +330,7 @@ protected:
   void NotifySend (uint32_t spaceAvailable);
   void NotifyDataRecv (void);
 
+  Callback<void, Ptr<Socket> >   m_closeUnblocks;
   Callback<void,Ptr<Socket> >    m_closeCompleted;
   Callback<void, Ptr<Socket> >   m_connectionSucceeded;
   Callback<void, Ptr<Socket> >   m_connectionFailed;