model: Major API changes

Interest and ContentObject are no longer derived from Header class.
Instead, they are encapsulating payload and, optionally, wire-formatted
Packet object.

Refs #1005 (http://redmine.named-data.net/)
diff --git a/model/cs/content-store-impl.h b/model/cs/content-store-impl.h
index ffe8038..9cd934e 100644
--- a/model/cs/content-store-impl.h
+++ b/model/cs/content-store-impl.h
@@ -44,8 +44,8 @@
   typedef Entry base_type;
 
 public:
-  EntryImpl (Ptr<ContentStore> cs, Ptr<const ContentObject> header, Ptr<const Packet> packet)
-    : Entry (cs, header, packet)
+  EntryImpl (Ptr<ContentStore> cs, Ptr<const ContentObject> data)
+    : Entry (cs, data)
     , item_ (0)
   {
   }
@@ -86,11 +86,11 @@
 
   // from ContentStore
 
-  virtual inline boost::tuple<Ptr<Packet>, Ptr<const ContentObject>, Ptr<const Packet> >
+  virtual inline Ptr<ContentObject>
   Lookup (Ptr<const Interest> interest);
 
   virtual inline bool
-  Add (Ptr<const ContentObject> header, Ptr<const Packet> packet);
+  Add (Ptr<const ContentObject> data);
 
   // virtual bool
   // Remove (Ptr<Interest> header);
@@ -156,7 +156,7 @@
 }
 
 template<class Policy>
-boost::tuple<Ptr<Packet>, Ptr<const ContentObject>, Ptr<const Packet> >
+Ptr<const ContentObject>
 ContentStoreImpl<Policy>::Lookup (Ptr<const Interest> interest)
 {
   NS_LOG_FUNCTION (this << interest->GetName ());
@@ -166,29 +166,27 @@
 
   if (node != this->end ())
     {
-      this->m_cacheHitsTrace (interest, node->payload ()->GetHeader ());
+      this->m_cacheHitsTrace (interest, node->payload ()->GetData ());
 
-      // NS_LOG_DEBUG ("cache hit with " << node->payload ()->GetHeader ()->GetName ());
-      return boost::make_tuple (node->payload ()->GetFullyFormedNdnPacket (),
-                                node->payload ()->GetHeader (),
-                                node->payload ()->GetPacket ());
+      Ptr<ContentObject> copy = Create<ContentObject> (node->payload ()->GetData ());
+      ConstCast<Packet> (copy->GetPayload ())->RemoveAllPacketTags ();
+      return copy;
     }
   else
     {
-      // NS_LOG_DEBUG ("cache miss for " << interest->GetName ());
       this->m_cacheMissesTrace (interest);
-      return boost::tuple<Ptr<Packet>, Ptr<ContentObject>, Ptr<Packet> > (0, 0, 0);
+      return 0;
     }
 }
 
 template<class Policy>
 bool
-ContentStoreImpl<Policy>::Add (Ptr<const ContentObject> header, Ptr<const Packet> packet)
+ContentStoreImpl<Policy>::Add (Ptr<const ContentObject> data)
 {
-  NS_LOG_FUNCTION (this << header->GetName ());
+  NS_LOG_FUNCTION (this << data->GetName ());
 
-  Ptr< entry > newEntry = Create< entry > (this, header, packet);
-  std::pair< typename super::iterator, bool > result = super::insert (header->GetName (), newEntry);
+  Ptr< entry > newEntry = Create< entry > (this, data);
+  std::pair< typename super::iterator, bool > result = super::insert (data->GetName (), newEntry);
 
   if (result.first != super::end ())
     {
diff --git a/model/cs/content-store-nocache.cc b/model/cs/content-store-nocache.cc
index 8814c13..c5749e2 100644
--- a/model/cs/content-store-nocache.cc
+++ b/model/cs/content-store-nocache.cc
@@ -55,15 +55,15 @@
 {
 }
 
-boost::tuple<Ptr<Packet>, Ptr<const ContentObject>, Ptr<const Packet> >
+Ptr<ContentObject>
 Nocache::Lookup (Ptr<const Interest> interest)
 {
   this->m_cacheMissesTrace (interest);
-  return boost::tuple<Ptr<Packet>, Ptr<const ContentObject>, Ptr<const Packet> > (0, 0, 0);
+  return 0;
 }
 
 bool
-Nocache::Add (Ptr<const ContentObject> header, Ptr<const Packet> packet)
+Nocache::Add (Ptr<const ContentObject> data)
 {
   return false;
 }
diff --git a/model/cs/content-store-nocache.h b/model/cs/content-store-nocache.h
index 6d38f40..79d1284 100644
--- a/model/cs/content-store-nocache.h
+++ b/model/cs/content-store-nocache.h
@@ -54,11 +54,11 @@
   virtual
   ~Nocache ();
 
-  virtual boost::tuple<Ptr<Packet>, Ptr<const ContentObject>, Ptr<const Packet> >
+  virtual Ptr<ContentObject>
   Lookup (Ptr<const Interest> interest);
 
   virtual bool
-  Add (Ptr<const ContentObject> header, Ptr<const Packet> packet);
+  Add (Ptr<const ContentObject> data);
 
   virtual void
   Print (std::ostream &os) const;
diff --git a/model/cs/content-store-with-freshness.h b/model/cs/content-store-with-freshness.h
index 81f8856..3ba871c 100644
--- a/model/cs/content-store-with-freshness.h
+++ b/model/cs/content-store-with-freshness.h
@@ -90,9 +90,9 @@
 
 template<class Policy>
 inline bool
-ContentStoreWithFreshness< Policy >::Add (Ptr<const ContentObject> header, Ptr<const Packet> packet)
+ContentStoreWithFreshness< Policy >::Add (Ptr<const ContentObject> data)
 {
-  bool ok = super::Add (header, packet);
+  bool ok = super::Add (data);
   if (!ok) return false;
 
   NS_LOG_DEBUG (header->GetName () << " added to cache");
diff --git a/model/cs/ndn-content-store.cc b/model/cs/ndn-content-store.cc
index c99d7ed..cfe362e 100644
--- a/model/cs/ndn-content-store.cc
+++ b/model/cs/ndn-content-store.cc
@@ -34,7 +34,7 @@
 
 NS_OBJECT_ENSURE_REGISTERED (ContentStore);
 
-TypeId 
+TypeId
 ContentStore::GetTypeId (void)
 {
   static TypeId tid = TypeId ("ns3::ndn::ContentStore")
@@ -60,24 +60,12 @@
 
 //////////////////////////////////////////////////////////////////////
 
-Entry::Entry (Ptr<ContentStore> cs, Ptr<const ContentObject> header, Ptr<const Packet> packet)
+Entry::Entry (Ptr<ContentStore> cs, Ptr<const ContentObject> data)
   : m_cs (cs)
-  , m_header (header)
-  , m_packet (packet->Copy ())
+  , m_data (data)
 {
 }
 
-Ptr<Packet>
-Entry::GetFullyFormedNdnPacket () const
-{
-  static ContentObjectTail tail; ///< \internal for optimization purposes
-
-  Ptr<Packet> packet = m_packet->Copy ();
-  packet->AddHeader (*m_header);
-  packet->AddTrailer (tail);
-  return packet;
-}
-
 const Name&
 Entry::GetName () const
 {
@@ -85,15 +73,9 @@
 }
 
 Ptr<const ContentObject>
-Entry::GetHeader () const
+Entry::GetData () const
 {
-  return m_header;
-}
-
-Ptr<const Packet>
-Entry::GetPacket () const
-{
-  return m_packet;
+  return m_data;
 }
 
 Ptr<ContentStore>
diff --git a/model/cs/ndn-content-store.h b/model/cs/ndn-content-store.h
index 54901d9..66e7667 100644
--- a/model/cs/ndn-content-store.h
+++ b/model/cs/ndn-content-store.h
@@ -36,13 +36,7 @@
 
 class ContentObject;
 class Interest;
-
-typedef Interest InterestHeader;
-typedef ContentObject ContentObjectHeader;
-
 class Name;
-typedef Name NameComponents;
-
 class ContentStore;
 
 namespace cs {
@@ -50,13 +44,6 @@
 /**
  * \ingroup ndn
  * \brief NDN content store entry
- *
- * Content store entry stores separately pseudo header and content of
- * ContentObject packet.  It is responsibility of the caller to
- * construct a fully formed NDN Packet by calling Copy(), AddHeader(),
- * AddTail() on the packet received by GetPacket() method.
- *
- * GetFullyFormedNdnPacket method provided as a convenience
  */
 class Entry : public SimpleRefCount<Entry>
 {
@@ -70,7 +57,7 @@
    * The constructor will make a copy of the supplied packet and calls
    * RemoveHeader and RemoveTail on the copy.
    */
-  Entry (Ptr<ContentStore> cs, Ptr<const ContentObject> header, Ptr<const Packet> packet);
+  Entry (Ptr<ContentStore> cs, Ptr<const ContentObject> data);
 
   /**
    * \brief Get prefix of the stored entry
@@ -84,21 +71,7 @@
    * \returns ContentObject of the stored entry
    */
   Ptr<const ContentObject>
-  GetHeader () const;
-
-  /**
-   * \brief Get content of the stored entry
-   * \returns content of the stored entry
-   */
-  Ptr<const Packet>
-  GetPacket () const;
-
-  /**
-   * \brief Convenience method to create a fully formed Ndn packet from stored header and content
-   * \returns A read-write copy of the packet with ContentObject and ContentObjectTail
-   */
-  Ptr<Packet>
-  GetFullyFormedNdnPacket () const;
+  GetData () const;
 
   /**
    * @brief Get pointer to access store, to which this entry is added
@@ -108,8 +81,7 @@
 
 private:
   Ptr<ContentStore> m_cs; ///< \brief content store to which entry is added
-  Ptr<const ContentObject> m_header; ///< \brief non-modifiable ContentObject
-  Ptr<Packet> m_packet; ///< \brief non-modifiable content of the ContentObject packet
+  Ptr<const ContentObject> m_data; ///< \brief non-modifiable ContentObject
 };
 
 } // namespace cs
@@ -147,7 +119,7 @@
    * If an entry is found, it is promoted to the top of most recent
    * used entries index, \see m_contentStore
    */
-  virtual boost::tuple<Ptr<Packet>, Ptr<const ContentObject>, Ptr<const Packet> >
+  virtual Ptr<ContentObject>
   Lookup (Ptr<const Interest> interest) = 0;
 
   /**
@@ -159,7 +131,7 @@
    * @returns true if an existing entry was updated, false otherwise
    */
   virtual bool
-  Add (Ptr<const ContentObject> header, Ptr<const Packet> packet) = 0;
+  Add (Ptr<const ContentObject> data) = 0;
 
   // /*
   //  * \brief Add a new content to the content store.