publisher: implement routing table dataset publisher

refs: #3631, #3634

Change-Id: I7e961fdd0857690bee65d2bdfa4cf3de90ccac06
diff --git a/src/tlv/nexthop.hpp b/src/tlv/nexthop.hpp
new file mode 100644
index 0000000..03666cc
--- /dev/null
+++ b/src/tlv/nexthop.hpp
@@ -0,0 +1,112 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2018,  The University of Memphis,
+ *                           Regents of the University of California,
+ *                           Arizona Board of Regents.
+ *
+ * This file is part of NLSR (Named-data Link State Routing).
+ * See AUTHORS.md for complete list of NLSR authors and contributors.
+ *
+ * NLSR is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NLSR 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
+ * NLSR, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+#ifndef NLSR_TLV_NEXTHOP_HPP
+#define NLSR_TLV_NEXTHOP_HPP
+
+#include <ndn-cxx/util/time.hpp>
+#include <ndn-cxx/encoding/block.hpp>
+#include <ndn-cxx/encoding/encoding-buffer.hpp>
+#include <ndn-cxx/encoding/tlv.hpp>
+#include <ndn-cxx/name.hpp>
+#include <boost/throw_exception.hpp>
+
+namespace nlsr {
+namespace tlv {
+
+/*! \brief Data abstraction for Nexthop
+ *
+ *   NextHop := NEXTHOP-TYPE TLV-LENGTH
+ *                Uri
+ *                Cost
+ *
+ * \sa https://redmine.named-data.net/projects/nlsr/wiki/Routing_Table_Dataset
+ */
+class NextHop
+{
+public:
+  class Error : public ndn::tlv::Error
+  {
+  public:
+    explicit
+    Error(const std::string& what)
+      : ndn::tlv::Error(what)
+    {
+    }
+  };
+
+  NextHop();
+
+  explicit
+  NextHop(const ndn::Block& block);
+
+  const std::string&
+  getUri() const
+  {
+    return m_uri;
+  }
+
+  NextHop&
+  setUri(const std::string& uri)
+  {
+    m_uri = uri;
+    m_wire.reset();
+    return *this;
+  }
+
+  double
+  getCost() const
+  {
+    return m_cost;
+  }
+
+  NextHop&
+  setCost(double cost)
+  {
+    m_cost = cost;
+    m_wire.reset();
+    return *this;
+  }
+
+  template<ndn::encoding::Tag TAG>
+  size_t
+  wireEncode(ndn::EncodingImpl<TAG>& block) const;
+
+  const ndn::Block&
+  wireEncode() const;
+
+  void
+  wireDecode(const ndn::Block& wire);
+
+private:
+  std::string m_uri;
+  double m_cost;
+
+  mutable ndn::Block m_wire;
+};
+
+std::ostream&
+operator<<(std::ostream& os, const NextHop& nexthop);
+
+} // namespace tlv
+} // namespace nlsr
+
+#endif // NLSR_TLV_NEXTHOP_HPP