face: introduce NullTransport and use it in several places

Refs: #4528
Change-Id: Icc7a77232bca1a700ce1319493c15a85d05d7488
diff --git a/daemon/face/face.hpp b/daemon/face/face.hpp
index f99bece..440bb4d 100644
--- a/daemon/face/face.hpp
+++ b/daemon/face/face.hpp
@@ -64,11 +64,7 @@
  *  LinkService is the upper part, which translates between network-layer packets
  *  and TLV blocks, and may provide additional services such as fragmentation and reassembly.
  */
-class Face
-#ifndef WITH_TESTS
-final
-#endif
-  : public std::enable_shared_from_this<Face>, noncopyable
+class Face FINAL_UNLESS_WITH_TESTS : public std::enable_shared_from_this<Face>, noncopyable
 {
 public:
   Face(unique_ptr<LinkService> service, unique_ptr<Transport> transport);
diff --git a/daemon/face/generic-link-service.hpp b/daemon/face/generic-link-service.hpp
index cd124c0..9bbe1b8 100644
--- a/daemon/face/generic-link-service.hpp
+++ b/daemon/face/generic-link-service.hpp
@@ -89,8 +89,8 @@
 /** \brief GenericLinkService is a LinkService that implements the NDNLPv2 protocol
  *  \sa https://redmine.named-data.net/projects/nfd/wiki/NDNLPv2
  */
-class GenericLinkService : public LinkService
-                         , protected virtual GenericLinkServiceCounters
+class GenericLinkService FINAL_UNLESS_WITH_TESTS : public LinkService
+                                                 , protected virtual GenericLinkServiceCounters
 {
 public:
   /** \brief Options that control the behavior of GenericLinkService
@@ -167,7 +167,7 @@
   setOptions(const Options& options);
 
   const Counters&
-  getCounters() const override;
+  getCounters() const OVERRIDE_WITH_TESTS_ELSE_FINAL;
 
 PROTECTED_WITH_TESTS_ELSE_PRIVATE: // send path
   /** \brief request an IDLE packet to transmit pending service fields
@@ -184,17 +184,17 @@
   /** \brief send Interest
    */
   void
-  doSendInterest(const Interest& interest) override;
+  doSendInterest(const Interest& interest) OVERRIDE_WITH_TESTS_ELSE_FINAL;
 
   /** \brief send Data
    */
   void
-  doSendData(const Data& data) override;
+  doSendData(const Data& data) OVERRIDE_WITH_TESTS_ELSE_FINAL;
 
   /** \brief send Nack
    */
   void
-  doSendNack(const ndn::lp::Nack& nack) override;
+  doSendNack(const ndn::lp::Nack& nack) OVERRIDE_WITH_TESTS_ELSE_FINAL;
 
 private: // send path
   /** \brief encode link protocol fields from tags onto an outgoing LpPacket
@@ -232,7 +232,7 @@
   /** \brief receive Packet from Transport
    */
   void
-  doReceivePacket(Transport::Packet&& packet) override;
+  doReceivePacket(Transport::Packet&& packet) OVERRIDE_WITH_TESTS_ELSE_FINAL;
 
   /** \brief decode incoming network-layer packet
    *  \param netPkt reassembled network-layer packet
diff --git a/daemon/face/null-face.cpp b/daemon/face/null-face.cpp
index 2ce5c98..77178c6 100644
--- a/daemon/face/null-face.cpp
+++ b/daemon/face/null-face.cpp
@@ -25,7 +25,7 @@
 
 #include "null-face.hpp"
 #include "null-link-service.hpp"
-#include "internal-transport.hpp"
+#include "null-transport.hpp"
 
 namespace nfd {
 namespace face {
@@ -36,7 +36,7 @@
   // FIB could restrict creating a nexthop record toward a non-local face in /localhost namespace.
   // Therefore, NullFace has scope=local to enable creating a "blackhole" FIB entry under /localhost.
   return make_shared<Face>(make_unique<NullLinkService>(),
-                           make_unique<InternalForwarderTransport>(uri, uri, ndn::nfd::FACE_SCOPE_LOCAL));
+                           make_unique<NullTransport>(uri, uri, ndn::nfd::FACE_SCOPE_LOCAL));
 }
 
 } // namespace face
diff --git a/daemon/face/null-transport.cpp b/daemon/face/null-transport.cpp
new file mode 100644
index 0000000..912bf25
--- /dev/null
+++ b/daemon/face/null-transport.cpp
@@ -0,0 +1,47 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2014-2019,  Regents of the University of California,
+ *                           Arizona Board of Regents,
+ *                           Colorado State University,
+ *                           University Pierre & Marie Curie, Sorbonne University,
+ *                           Washington University in St. Louis,
+ *                           Beijing Institute of Technology,
+ *                           The University of Memphis.
+ *
+ * This file is part of NFD (Named Data Networking Forwarding Daemon).
+ * See AUTHORS.md for complete list of NFD authors and contributors.
+ *
+ * NFD 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.
+ *
+ * NFD 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
+ * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "null-transport.hpp"
+
+namespace nfd {
+namespace face {
+
+NFD_LOG_INIT(NullTransport);
+
+NullTransport::NullTransport(const FaceUri& localUri, const FaceUri& remoteUri,
+                             ndn::nfd::FaceScope scope, ndn::nfd::FacePersistency persistency)
+{
+  this->setLocalUri(localUri);
+  this->setRemoteUri(remoteUri);
+  this->setScope(scope);
+  this->setPersistency(persistency);
+  this->setLinkType(ndn::nfd::LINK_TYPE_POINT_TO_POINT);
+  this->setMtu(MTU_UNLIMITED);
+
+  NFD_LOG_FACE_DEBUG("Creating transport");
+}
+
+} // namespace face
+} // namespace nfd
diff --git a/daemon/face/null-transport.hpp b/daemon/face/null-transport.hpp
new file mode 100644
index 0000000..9f8e54e
--- /dev/null
+++ b/daemon/face/null-transport.hpp
@@ -0,0 +1,62 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2014-2019,  Regents of the University of California,
+ *                           Arizona Board of Regents,
+ *                           Colorado State University,
+ *                           University Pierre & Marie Curie, Sorbonne University,
+ *                           Washington University in St. Louis,
+ *                           Beijing Institute of Technology,
+ *                           The University of Memphis.
+ *
+ * This file is part of NFD (Named Data Networking Forwarding Daemon).
+ * See AUTHORS.md for complete list of NFD authors and contributors.
+ *
+ * NFD 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.
+ *
+ * NFD 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
+ * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef NFD_DAEMON_FACE_NULL_TRANSPORT_HPP
+#define NFD_DAEMON_FACE_NULL_TRANSPORT_HPP
+
+#include "transport.hpp"
+
+namespace nfd {
+namespace face {
+
+/** \brief A Transport that drops every packet.
+ */
+class NullTransport FINAL_UNLESS_WITH_TESTS : public Transport
+{
+public:
+  explicit
+  NullTransport(const FaceUri& localUri = FaceUri("null://"),
+                const FaceUri& remoteUri = FaceUri("null://"),
+                ndn::nfd::FaceScope scope = ndn::nfd::FACE_SCOPE_NON_LOCAL,
+                ndn::nfd::FacePersistency persistency = ndn::nfd::FACE_PERSISTENCY_PERMANENT);
+
+protected:
+  void
+  doClose() OVERRIDE_WITH_TESTS_ELSE_FINAL
+  {
+    setState(TransportState::CLOSED);
+  }
+
+private:
+  void
+  doSend(Packet&&) OVERRIDE_WITH_TESTS_ELSE_FINAL
+  {
+  }
+};
+
+} // namespace face
+} // namespace nfd
+
+#endif // NFD_DAEMON_FACE_NULL_TRANSPORT_HPP