mgmt refactoring: Refactor InternalFace

InternalFace is now exclusively for internal use by NFD's forwarding
pipelines.  A separate InternalClientFace has been introduced, intended
to be used by the NFD internal applications, including FIB, Face, RIB
manager, and others.

Change-Id: I4a06b9d05b1613a456c6267582091924557d73be
Refs: #2107
diff --git a/daemon/face/internal-client-face.cpp b/daemon/face/internal-client-face.cpp
new file mode 100644
index 0000000..510b087
--- /dev/null
+++ b/daemon/face/internal-client-face.cpp
@@ -0,0 +1,99 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2015,  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 "internal-client-face.hpp"
+#include "internal-face.hpp"
+#include "core/global-io.hpp"
+
+#include <ndn-cxx/management/nfd-local-control-header.hpp>
+
+namespace nfd {
+
+void
+InternalClientFace::Transport::receive(const Block& block)
+{
+  if (m_receiveCallback) {
+    m_receiveCallback(block);
+  }
+}
+
+void
+InternalClientFace::Transport::close()
+{
+}
+
+void
+InternalClientFace::Transport::send(const Block& wire)
+{
+  onSendBlock(wire);
+}
+
+void
+InternalClientFace::Transport::send(const Block& header, const Block& payload)
+{
+  ndn::EncodingBuffer encoder(header.size() + payload.size(), header.size() + payload.size());
+  encoder.appendByteArray(header.wire(), header.size());
+  encoder.appendByteArray(payload.wire(), payload.size());
+
+  this->send(encoder.block());
+}
+
+void
+InternalClientFace::Transport::pause()
+{
+}
+
+void
+InternalClientFace::Transport::resume()
+{
+}
+
+InternalClientFace::InternalClientFace(const shared_ptr<InternalFace>& face,
+                                       const shared_ptr<InternalClientFace::Transport>& transport,
+                                       ndn::KeyChain& keyChain)
+  : ndn::Face(transport, getGlobalIoService(), keyChain)
+  , m_face(face)
+  , m_transport(transport)
+{
+  construct();
+}
+
+void
+InternalClientFace::construct()
+{
+  m_face->onSendInterest.connect(bind(&InternalClientFace::receive<Interest>, this, _1));
+  m_face->onSendData.connect(bind(&InternalClientFace::receive<Data>, this, _1));
+  m_transport->onSendBlock.connect(bind(&InternalFace::receive, m_face, _1));
+}
+
+shared_ptr<InternalClientFace>
+makeInternalClientFace(const shared_ptr<InternalFace>& face,
+                       ndn::KeyChain& keyChain)
+{
+  auto transport = make_shared<InternalClientFace::Transport>();
+  return shared_ptr<InternalClientFace>(new InternalClientFace(face, transport, keyChain));
+}
+
+} // namespace nfd
diff --git a/daemon/face/internal-client-face.hpp b/daemon/face/internal-client-face.hpp
new file mode 100644
index 0000000..8eb3c46
--- /dev/null
+++ b/daemon/face/internal-client-face.hpp
@@ -0,0 +1,118 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2015,  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_INTERNAL_CLIENT_FACE_HPP
+#define NFD_DAEMON_FACE_INTERNAL_CLIENT_FACE_HPP
+
+#include "common.hpp"
+
+#include <ndn-cxx/face.hpp>
+#include <ndn-cxx/security/key-chain.hpp>
+#include <ndn-cxx/transport/transport.hpp>
+
+namespace nfd {
+
+class InternalFace;
+class InternalClientFace;
+
+shared_ptr<InternalClientFace>
+makeInternalClientFace(const shared_ptr<InternalFace>& face, ndn::KeyChain& keyChain);
+
+/** \brief a client face that is connected to NFD InternalFace
+ */
+class InternalClientFace : public ndn::Face
+{
+public:
+  template<typename Packet>
+  void
+  receive(const Packet& packet);
+
+private:
+  class Transport : public ndn::Transport
+  {
+  public:
+    signal::Signal<Transport, Block> onSendBlock;
+
+    void
+    receive(const Block& block);
+
+    virtual void
+    close() DECL_OVERRIDE;
+
+    virtual void
+    send(const Block& wire) DECL_OVERRIDE;
+
+    virtual void
+    send(const Block& header, const Block& payload) DECL_OVERRIDE;
+
+    virtual void
+    pause() DECL_OVERRIDE;
+
+    virtual void
+    resume() DECL_OVERRIDE;
+  };
+
+private:
+  InternalClientFace(const shared_ptr<InternalFace>& face,
+                     const shared_ptr<InternalClientFace::Transport>& transport,
+                     ndn::KeyChain& keyChain);
+
+  void
+  construct();
+
+  friend shared_ptr<InternalClientFace>
+  makeInternalClientFace(const shared_ptr<InternalFace>& face,
+                         ndn::KeyChain& keyChain);
+
+private:
+  shared_ptr<InternalFace> m_face;
+  shared_ptr<InternalClientFace::Transport> m_transport;
+};
+
+template<typename Packet>
+void
+InternalClientFace::receive(const Packet& packet)
+{
+  if (!packet.getLocalControlHeader().empty(ndn::nfd::LocalControlHeader::ENCODE_ALL)) {
+
+    Block header = packet.getLocalControlHeader()
+                         .wireEncode(packet, ndn::nfd::LocalControlHeader::ENCODE_ALL);
+    Block payload = packet.wireEncode();
+
+    ndn::EncodingBuffer encoder(header.size() + payload.size(),
+                                header.size() + payload.size());
+    encoder.appendByteArray(header.wire(), header.size());
+    encoder.appendByteArray(payload.wire(), payload.size());
+
+    m_transport->receive(encoder.block());
+  }
+  else {
+    m_transport->receive(packet.wireEncode());
+  }
+}
+
+} // namespace nfd
+
+#endif // NFD_DAEMON_FACE_INTERNAL_CLIENT_FACE_HPP
diff --git a/daemon/face/internal-face.cpp b/daemon/face/internal-face.cpp
new file mode 100644
index 0000000..c5ab2ca
--- /dev/null
+++ b/daemon/face/internal-face.cpp
@@ -0,0 +1,93 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2015,  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 "internal-face.hpp"
+
+namespace nfd {
+
+InternalFace::InternalFace()
+  : Face(FaceUri("internal://"), FaceUri("internal://"), true)
+{
+}
+
+void
+InternalFace::sendInterest(const Interest& interest)
+{
+  this->emitSignal(onSendInterest, interest);
+}
+
+void
+InternalFace::sendData(const Data& data)
+{
+  this->emitSignal(onSendData, data);
+}
+
+void
+InternalFace::close()
+{
+}
+
+void
+InternalFace::receive(const Block& blockFromClient)
+{
+  const Block& payLoad = ndn::nfd::LocalControlHeader::getPayload(blockFromClient);
+  if (payLoad.type() == ndn::tlv::Interest) {
+    receiveInterest(*extractPacketFromBlock<Interest>(blockFromClient, payLoad));
+  }
+  else if (payLoad.type() == ndn::tlv::Data) {
+    receiveData(*extractPacketFromBlock<Data>(blockFromClient, payLoad));
+  }
+}
+
+void
+InternalFace::receiveInterest(const Interest& interest)
+{
+  this->emitSignal(onReceiveInterest, interest);
+}
+
+void
+InternalFace::receiveData(const Data& data)
+{
+  this->emitSignal(onReceiveData, data);
+}
+
+template<typename Packet>
+shared_ptr<Packet>
+InternalFace::extractPacketFromBlock(const Block& blockFromClient, const Block& payLoad)
+{
+  auto packet = make_shared<Packet>(payLoad);
+  if (&payLoad != &blockFromClient) {
+    packet->getLocalControlHeader().wireDecode(blockFromClient);
+  }
+  return packet;
+}
+
+template shared_ptr<Interest>
+InternalFace::extractPacketFromBlock<Interest>(const Block& blockFromClient, const Block& payLoad);
+
+template shared_ptr<Data>
+InternalFace::extractPacketFromBlock<Data>(const Block& blockFromClient, const Block& payLoad);
+
+} // namespace nfd
diff --git a/daemon/face/internal-face.hpp b/daemon/face/internal-face.hpp
new file mode 100644
index 0000000..1014fca
--- /dev/null
+++ b/daemon/face/internal-face.hpp
@@ -0,0 +1,102 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2015,  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_INTERNAL_FACE_HPP
+#define NFD_DAEMON_FACE_INTERNAL_FACE_HPP
+
+#include "face.hpp"
+
+namespace nfd {
+
+/**
+ * @brief represents a face for internal use in NFD.
+ */
+class InternalFace : public Face
+{
+public:
+
+  InternalFace();
+
+  virtual void
+  sendInterest(const Interest& interest) DECL_OVERRIDE;
+
+  virtual void
+  sendData(const Data& data) DECL_OVERRIDE;
+
+  virtual void
+  close() DECL_OVERRIDE;
+
+  /**
+   * @brief receive a block from a client face
+   *
+   * step1. extracte the packet payload from the received block.
+   * step2. check the type (either Interest or Data) through the payload.
+   * step3. call receiveInterest / receiveData respectively according to the type.
+   *
+   * @param blockFromClient the block from a client face
+   */
+  void
+  receive(const Block& blockFromClient);
+
+  /**
+   * @brief receive an Interest from a client face
+   *
+   * emit the onReceiveInterest signal.
+   *
+   * @param interest the received Interest packet
+   */
+  void
+  receiveInterest(const Interest& interest);
+
+  /**
+   * @brief receive a Data from a client face
+   *
+   * emit the onReceiveData signal.
+   *
+   * @param data the received Data packet
+   */
+  void
+  receiveData(const Data& data);
+
+  /**
+   * @brief compose the whole packet from the received block after payload is extracted
+   *
+   * construct a packet from the extracted payload, and then decode the localControlHeader if the
+   * received block holds more information than the payload.
+   *
+   * @tparam Packet the type of packet, Interest or Data
+   * @param blockFromClient the received block
+   * @param payLoad the extracted payload
+   *
+   * @return a complete packet
+   */
+  template<typename Packet>
+  static shared_ptr<Packet>
+  extractPacketFromBlock(const Block& blockFromClient, const Block& payLoad);
+};
+
+} // namespace nfd
+
+#endif // NFD_DAEMON_FACE_INTERNAL_FACE_HPP