csma: Add support for flow control and BQL

examples/routing/global-injection-slash32.cc

@@ -83,10 +83,12 @@ main (int argc, char *argv[])
   Ptr<CsmaNetDevice> deviceA = CreateObject<CsmaNetDevice> ();
   deviceA->SetAddress (Mac48Address::Allocate ());
   nA->AddDevice (deviceA);
+  deviceA->SetQueue (CreateObject<DropTailQueue<Packet> > ());
 
   Ptr<CsmaNetDevice> deviceC = CreateObject<CsmaNetDevice> ();
   deviceC->SetAddress (Mac48Address::Allocate ());
   nC->AddDevice (deviceC);
+  deviceC->SetQueue (CreateObject<DropTailQueue<Packet> > ());
 
   // Later, we add IP addresses.
   Ipv4AddressHelper ipv4;

examples/routing/global-routing-slash32.cc

@@ -69,10 +69,12 @@ main (int argc, char *argv[])
   Ptr<CsmaNetDevice> deviceA = CreateObject<CsmaNetDevice> ();
   deviceA->SetAddress (Mac48Address::Allocate ());
   nA->AddDevice (deviceA);
+  deviceA->SetQueue (CreateObject<DropTailQueue<Packet> > ());
 
   Ptr<CsmaNetDevice> deviceC = CreateObject<CsmaNetDevice> ();
   deviceC->SetAddress (Mac48Address::Allocate ());
   nC->AddDevice (deviceC);
+  deviceC->SetQueue (CreateObject<DropTailQueue<Packet> > ());
 
   // Later, we add IP addresses.
   Ipv4AddressHelper ipv4;

examples/routing/static-routing-slash32.cc

@@ -69,10 +69,12 @@ main (int argc, char *argv[])
   Ptr<CsmaNetDevice> deviceA = CreateObject<CsmaNetDevice> ();
   deviceA->SetAddress (Mac48Address::Allocate ());
   nA->AddDevice (deviceA);
+  deviceA->SetQueue (CreateObject<DropTailQueue<Packet> > ());
 
   Ptr<CsmaNetDevice> deviceC = CreateObject<CsmaNetDevice> ();
   deviceC->SetAddress (Mac48Address::Allocate ());
   nC->AddDevice (deviceC);
+  deviceC->SetQueue (CreateObject<DropTailQueue<Packet> > ());
 
   // Later, we add IP addresses.
   Ipv4AddressHelper ipv4;

src/csma/model/csma-net-device.cc

@@ -32,6 +32,7 @@
 #include "ns3/trace-source-accessor.h"
 #include "csma-net-device.h"
 #include "csma-channel.h"
+#include "ns3/net-device-queue-interface.h"
 
 namespace ns3 {
 
@@ -189,7 +190,7 @@ CsmaNetDevice::CsmaNetDevice ()
   NS_LOG_FUNCTION (this);
   m_txMachineState = READY;
   m_tInterframeGap = Seconds (0);
-  m_channel = 0; 
+  m_channel = 0;
 
   // 
   // We would like to let the attribute system take care of initializing the 
@@ -217,9 +218,45 @@ CsmaNetDevice::DoDispose ()
   NS_LOG_FUNCTION_NOARGS ();
   m_channel = 0;
   m_node = 0;
+  m_queue = 0;
+  m_queueInterface = 0;
   NetDevice::DoDispose ();
 }
 
+void
+CsmaNetDevice::DoInitialize (void)
+{
+  if (m_queueInterface)
+    {
+      NS_ASSERT_MSG (m_queue != 0, "A Queue object has not been attached to the device");
+
+      // connect the traced callbacks of m_queue to the static methods provided by
+      // the NetDeviceQueue class to support flow control and dynamic queue limits.
+      // This could not be done in NotifyNewAggregate because at that time we are
+      // not guaranteed that a queue has been attached to the netdevice
+      m_queueInterface->ConnectQueueTraces (m_queue, 0);
+    }
+
+  NetDevice::DoInitialize ();
+}
+
+void
+CsmaNetDevice::NotifyNewAggregate (void)
+{
+  NS_LOG_FUNCTION (this);
+  if (m_queueInterface == 0)
+    {
+      Ptr<NetDeviceQueueInterface> ndqi = this->GetObject<NetDeviceQueueInterface> ();
+      //verify that it's a valid netdevice queue interface and that
+      //the netdevice queue interface was not set before
+      if (ndqi != 0)
+        {
+          m_queueInterface = ndqi;
+        }
+    }
+  NetDevice::NotifyNewAggregate ();
+}
+
 void
 CsmaNetDevice::SetEncapsulationMode (enum EncapsulationMode mode)
 {

src/csma/model/csma-net-device.h

@@ -39,6 +39,7 @@ namespace ns3 {
 template <typename Item> class Queue;
 class CsmaChannel;
 class ErrorModel;
+class NetDeviceQueueInterface;
 
 /** 
  * \defgroup csma CSMA Network Device
@@ -128,7 +129,7 @@ public:
    *
    * The CsmaNetDevice "owns" a queue.  This queue may be set by higher
    * level topology objects to implement a particular queueing method such as
-   * DropTail or RED.
+   * DropTail.
    *
    * \see Queue
    * \see DropTailQueue
@@ -356,6 +357,9 @@ protected:
    */
   void AddHeader (Ptr<Packet> p, Mac48Address source, Mac48Address dest, uint16_t protocolNumber);
 
+  virtual void DoInitialize (void);
+  virtual void NotifyNewAggregate (void);
+
 private:
 
   /**
@@ -683,6 +687,11 @@ private:
    */
   Ptr<Node> m_node;
 
+  /**
+   * NetDevice queue interface.
+   */
+  Ptr<NetDeviceQueueInterface> m_queueInterface;
+
   /**
    * The MAC address which has been assigned to this device.
    */