Includes cleanup + layer 2 link failure detection (untested)

src/internet-stack/ipv4-interface.cc

@@ -42,7 +42,8 @@ Ipv4Interface::GetTypeId (void)
     .AddAttribute ("ArpCache",
                    "The arp cache for this ipv4 interface",
                    PointerValue (0),
-                   MakePointerAccessor (&Ipv4Interface::m_cache),
+                   MakePointerAccessor (&Ipv4Interface::SetArpCache, 
+                                        &Ipv4Interface::GetArpCache),
                    MakePointerChecker<ArpCache> ())
     ;
     ;
@@ -128,6 +129,18 @@ Ipv4Interface::GetMetric (void) const
   return m_metric;
 }
 
+void
+Ipv4Interface::SetArpCache (Ptr<ArpCache> a)
+{
+  m_cache = a;
+}
+
+Ptr<ArpCache>
+Ipv4Interface::GetArpCache () const
+{
+  return m_cache;
+}
+
 /**
  * These are IP interface states and may be distinct from 
  * NetDevice states, such as found in real implementations

src/internet-stack/ipv4-interface.h

@@ -56,12 +56,17 @@ public:
 
   void SetNode (Ptr<Node> node); 
   void SetDevice (Ptr<NetDevice> device);
+  void SetArpCache (Ptr<ArpCache>);
 
   /**
    * \returns the underlying NetDevice. This method cannot return zero.
    */
   Ptr<NetDevice> GetDevice (void) const;
-
+  /**
+   * \return ARP cache used by this interface
+   */
+  Ptr<ArpCache> GetArpCache () const;
+  
   /**
    * \param metric configured routing metric (cost) of this interface
    *

src/internet-stack/wscript

@@ -108,6 +108,11 @@ def build(bld):
         'tcp-header.h',
         'sequence-number.h',
         'icmpv4.h',
+        # used by routing
+        'ipv4-interface.h', 
+        'ipv4-l3-protocol.h',
+        'arp-cache.h',
+        'sgi-hashmap.h',
         ]
 
     if bld.env['NSC_ENABLED']: