Adding nsync for NLSR
diff --git a/nsync/src/sync-interest-table.cc b/nsync/src/sync-interest-table.cc
new file mode 100644
index 0000000..a378950
--- /dev/null
+++ b/nsync/src/sync-interest-table.cc
@@ -0,0 +1,123 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2012 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: Zhenkai Zhu <zhenkai@cs.ucla.edu>
+ *         Chaoyi Bian <bcy@pku.edu.cn>
+ *	   Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#include "sync-interest-table.h"
+#include "sync-logging.h"
+using namespace std;
+
+INIT_LOGGER ("SyncInterestTable");
+
+namespace Sync
+{
+
+SyncInterestTable::SyncInterestTable (boost::asio::io_service& io, ndn::time::Duration lifetime)
+  : m_entryLifetime (lifetime)
+  , m_scheduler(io)
+{
+  m_scheduler.schedulePeriodicEvent (ndn::time::seconds (4), ndn::time::seconds (4),
+                                     ndn::bind(&SyncInterestTable::expireInterests, this));
+}
+
+SyncInterestTable::~SyncInterestTable ()
+{
+}
+
+Interest
+SyncInterestTable::pop ()
+{
+  if (m_table.size () == 0)
+    BOOST_THROW_EXCEPTION (Error::InterestTableIsEmpty ());
+
+  Interest ret = *m_table.begin ();
+  m_table.erase (m_table.begin ());
+
+  return ret;
+}
+
+bool
+SyncInterestTable::insert (DigestConstPtr digest, const string &name, bool unknownState/*=false*/)
+{
+  bool existent = false;
+  
+  InterestContainer::index<named>::type::iterator it = m_table.get<named> ().find (name);
+  if (it != m_table.end())
+    {
+      existent = true;
+      m_table.erase (it);
+    }
+  m_table.insert (Interest (digest, name, unknownState));
+
+  return existent;
+}
+
+uint32_t
+SyncInterestTable::size () const
+{
+  return m_table.size ();
+}
+
+bool
+SyncInterestTable::remove (const string &name)
+{
+  InterestContainer::index<named>::type::iterator item = m_table.get<named> ().find (name);
+  if (item != m_table.get<named> ().end ())
+    {
+      m_table.get<named> ().erase (name);
+      return true;
+    }
+
+  return false;
+}
+
+bool
+SyncInterestTable::remove (DigestConstPtr digest)
+{
+  InterestContainer::index<hashed>::type::iterator item = m_table.get<hashed> ().find (digest);
+  if (item != m_table.get<hashed> ().end ())
+    {
+      m_table.get<hashed> ().erase (digest); // erase all records associated with the digest
+      return true;
+    }
+  return false;
+}
+
+void SyncInterestTable::expireInterests ()
+{ 
+  uint32_t count = 0;
+  ndn::time::Point expireTime = ndn::time::now() - m_entryLifetime;
+  
+  while (m_table.size () > 0)
+    {
+      InterestContainer::index<timed>::type::iterator item = m_table.get<timed> ().begin ();
+      
+      if (item->m_time <= expireTime)
+        {
+          m_table.get<timed> ().erase (item);
+          count ++;
+        }
+      else
+        break;
+  }
+}
+
+
+}