network: Add a Remove method to the Queue base class

src/network/utils/drop-tail-queue.cc

@@ -72,6 +72,20 @@ DropTailQueue::DoDequeue (void)
   return item;
 }
 
+Ptr<QueueItem>
+DropTailQueue::DoRemove (void)
+{
+  NS_LOG_FUNCTION (this);
+  NS_ASSERT (m_packets.size () == GetNPackets ());
+
+  Ptr<QueueItem> item = m_packets.front ();
+  m_packets.pop ();
+
+  NS_LOG_LOGIC ("Removed " << item);
+
+  return item;
+}
+
 Ptr<const QueueItem>
 DropTailQueue::DoPeek (void) const
 {

src/network/utils/drop-tail-queue.h

@@ -49,6 +49,7 @@ public:
 private:
   virtual bool DoEnqueue (Ptr<QueueItem> item);
   virtual Ptr<QueueItem> DoDequeue (void);
+  virtual Ptr<QueueItem> DoRemove (void);
   virtual Ptr<const QueueItem> DoPeek (void) const;
 
   std::queue<Ptr<QueueItem> > m_packets; //!< the items in the queue

src/network/utils/queue.cc

@@ -158,6 +158,32 @@ Queue::Dequeue (void)
   return item;
 }
 
+Ptr<QueueItem>
+Queue::Remove (void)
+{
+  NS_LOG_FUNCTION (this);
+
+  if (m_nPackets.Get () == 0)
+    {
+      NS_LOG_LOGIC ("Queue empty");
+      return 0;
+    }
+
+  Ptr<QueueItem> item = DoRemove ();
+
+  if (item != 0)
+    {
+      NS_ASSERT (m_nBytes.Get () >= item->GetPacketSize ());
+      NS_ASSERT (m_nPackets.Get () > 0);
+
+      m_nBytes -= item->GetPacketSize ();
+      m_nPackets--;
+
+      Drop (item);
+    }
+  return item;
+}
+
 void
 Queue::DequeueAll (void)
 {

src/network/utils/queue.h

@@ -64,10 +64,15 @@ public:
    */
   bool Enqueue (Ptr<QueueItem> item);
   /**
-   * Remove an item from the front of the Queue
+   * Remove an item from the front of the Queue, counting it as dequeued
    * \return 0 if the operation was not successful; the item otherwise.
    */
   Ptr<QueueItem> Dequeue (void);
+  /**
+   * Remove an item from the front of the Queue, counting it as dropped
+   * \return 0 if the operation was not successful; the item otherwise.
+   */
+  Ptr<QueueItem>  Remove (void);
   /**
    * Get a copy of the item at the front of the queue without removing it
    * \return 0 if the operation was not successful; the item otherwise.
@@ -221,10 +226,15 @@ private:
    */
   virtual bool DoEnqueue (Ptr<QueueItem> item) = 0;
   /**
-   * Pull an item from the queue
+   * Pull the item to dequeue from the queue
    * \return the item.
    */
   virtual Ptr<QueueItem> DoDequeue (void) = 0;
+  /**
+   * Pull the item to drop from the queue
+   * \return the item.
+   */
+  virtual Ptr<QueueItem> DoRemove (void) = 0;
   /**
    * Peek the front item in the queue
    * \return the item.