ContentStore with hash table library were added

diff --git a/model/ndn_contentstore.h b/model/ndn_contentstore.h
new file mode 100644
index 0000000..7e49fb6
--- /dev/null
+++ b/model/ndn_contentstore.h
@@ -0,0 +1,83 @@
+/* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2011 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Ilya Moiseenko <iliamo@cs.ucla.edu>
+ */
+
+#ifndef ndn_contentstore_h
+#define	ndn_contentstore_h
+
+#include <ns3/system-mutex.h>
+#include <list>
+#include <string>
+#include "uthash.h"
+
+using namespace std;
+
+//size of content store
+#define NDN_CONTENT_STORE_SIZE 100
+
+namespace  ns3
+{
+namespace NDNabstraction
+{
+    
+class CsEntry;
+typedef list<CsEntry*>::iterator CsLruIterator;
+    
+//structure for CS entry
+struct CsEntry
+{
+    char *contentName;
+    int contentSize;
+    
+	CsLruIterator lruPosition;
+    UT_hash_handle hh;         /* makes this structure hashable */
+};
+
+
+class ContentStore
+{
+public:
+	ContentStore( int max_size=NDN_CONTENT_STORE_SIZE );
+	virtual ~ContentStore( );
+    
+	// Find corresponding CS entry for the given content name
+	CsEntry* Lookup( const char *prefix );
+	//bool isValid( const CsIterator &it ) { return it!=_cs.end(); }
+	
+	// Add new content to the content store. Old content will be replaced
+	void Add( const char *contentName, int contentSize );
+    
+	// Dump content store entries
+	void Dump( );
+    
+protected:
+	//move the given CS entry to the head of the list
+	void Promote( CsEntry &entry );
+    
+private:
+	int                   m_maxSize; // maximum number of entries in cache
+    
+    struct CsEntry  *m_contentStore;     // actual content store
+	list<CsEntry*>			  m_LRU;	// LRU index of the content store
+	SystemMutex				m_csMutex;   // just to make sure we are not
+};
+    
+}
+}
+#endif