src/face.cpp - ndn-cxx - Gitiles

 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
  * Copyright (c) 2013-2016 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
  * ndn-cxx library is free software: you can redistribute it and/or modify it under the
  * terms of the GNU Lesser General Public License as published by the Free Software
  * Foundation, either version 3 of the License, or (at your option) any later version.
  *
  * ndn-cxx library 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 Lesser General Public License for more details.
  *
  * You should have received copies of the GNU General Public License and GNU Lesser
  * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
  * <http://www.gnu.org/licenses/>.
  *
  * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
  */

 #include "face.hpp"
 #include "detail/face-impl.hpp"

 #include "encoding/tlv.hpp"
 #include "security/key-chain.hpp"
 #include "security/signing-helpers.hpp"
 #include "util/time.hpp"
 #include "util/random.hpp"
 #include "util/face-uri.hpp"

 // A callback scheduled through io.post and io.dispatch may be invoked after the face
 // is destructed. To prevent this situation, these macros captures Face::m_impl as weak_ptr,
 // and skips callback execution if the face has been destructed.
 #define IO_CAPTURE_WEAK_IMPL(OP) \
   { \
     weak_ptr<Impl> implWeak(m_impl); \
     m_ioService.OP([=] { \
       auto impl = implWeak.lock(); \
       if (impl != nullptr) {
 #define IO_CAPTURE_WEAK_IMPL_END \
       } \
     }); \
   }

 namespace ndn {

 Face::Face(shared_ptr<Transport> transport)
   : m_internalIoService(new boost::asio::io_service())
   , m_ioService(*m_internalIoService)
   , m_internalKeyChain(new KeyChain())
   , m_impl(make_shared<Impl>(*this))
 {
   construct(transport, *m_internalKeyChain);
 }

 Face::Face(boost::asio::io_service& ioService)
   : m_ioService(ioService)
   , m_internalKeyChain(new KeyChain())
   , m_impl(make_shared<Impl>(*this))
 {
   construct(nullptr, *m_internalKeyChain);
 }

 Face::Face(const std::string& host, const std::string& port)
   : m_internalIoService(new boost::asio::io_service())
   , m_ioService(*m_internalIoService)
   , m_internalKeyChain(new KeyChain())
   , m_impl(make_shared<Impl>(*this))
 {
   construct(make_shared<TcpTransport>(host, port), *m_internalKeyChain);
 }

 Face::Face(shared_ptr<Transport> transport, KeyChain& keyChain)
   : m_internalIoService(new boost::asio::io_service())
   , m_ioService(*m_internalIoService)
   , m_impl(make_shared<Impl>(*this))
 {
   construct(transport, keyChain);
 }

 Face::Face(shared_ptr<Transport> transport, boost::asio::io_service& ioService)
   : m_ioService(ioService)
   , m_internalKeyChain(new KeyChain())
   , m_impl(make_shared<Impl>(*this))
 {
   construct(transport, *m_internalKeyChain);
 }

 Face::Face(shared_ptr<Transport> transport, boost::asio::io_service& ioService, KeyChain& keyChain)
   : m_ioService(ioService)
   , m_impl(make_shared<Impl>(*this))
 {
   construct(transport, keyChain);
 }

 shared_ptr<Transport>
 Face::makeDefaultTransport()
 {
   // transport=unix:///var/run/nfd.sock
   // transport=tcp://localhost:6363

   std::string transportUri;

   const char* transportEnviron = getenv("NDN_CLIENT_TRANSPORT");
   if (transportEnviron != nullptr) {
     transportUri = transportEnviron;
   }
   else {
     ConfigFile config;
     transportUri = config.getParsedConfiguration().get<std::string>("transport", "");
   }

   if (transportUri.empty()) {
     // transport not specified, use default Unix transport.
     return UnixTransport::create("");
   }

   std::string protocol;
   try {
     util::FaceUri uri(transportUri);
     protocol = uri.getScheme();

     if (protocol == "unix") {
       return UnixTransport::create(transportUri);
     }
     else if (protocol == "tcp" || protocol == "tcp4" || protocol == "tcp6") {
       return TcpTransport::create(transportUri);
     }
     else {
       BOOST_THROW_EXCEPTION(ConfigFile::Error("Unsupported transport protocol \"" + protocol + "\""));
     }
   }
   catch (const Transport::Error& error) {
     BOOST_THROW_EXCEPTION(ConfigFile::Error(error.what()));
   }
   catch (const util::FaceUri::Error& error) {
     BOOST_THROW_EXCEPTION(ConfigFile::Error(error.what()));
   }
 }

 void
 Face::construct(shared_ptr<Transport> transport, KeyChain& keyChain)
 {
   if (transport == nullptr) {
     transport = makeDefaultTransport();
   }
   BOOST_ASSERT(transport != nullptr);
   m_transport = transport;

   m_nfdController.reset(new nfd::Controller(*this, keyChain));

   IO_CAPTURE_WEAK_IMPL(post) {
     impl->ensureConnected(false);
   } IO_CAPTURE_WEAK_IMPL_END
 }

 Face::~Face() = default;

 shared_ptr<Transport>
 Face::getTransport()
 {
   return m_transport;
 }

 const PendingInterestId*
 Face::expressInterest(const Interest& interest,
                       const DataCallback& afterSatisfied,
                       const NackCallback& afterNacked,
                       const TimeoutCallback& afterTimeout)
 {
   shared_ptr<Interest> interestToExpress = make_shared<Interest>(interest);

   // Use `interestToExpress` to avoid wire format creation for the original Interest
   if (interestToExpress->wireEncode().size() > MAX_NDN_PACKET_SIZE) {
     BOOST_THROW_EXCEPTION(Error("Interest size exceeds maximum limit"));
   }

   // If the same ioService thread, dispatch directly calls the method
   IO_CAPTURE_WEAK_IMPL(dispatch) {
     impl->asyncExpressInterest(interestToExpress, afterSatisfied, afterNacked, afterTimeout);
   } IO_CAPTURE_WEAK_IMPL_END

   return reinterpret_cast<const PendingInterestId*>(interestToExpress.get());
 }

 const PendingInterestId*
 Face::expressInterest(const Interest& interest,
                       const OnData& onData,
                       const OnTimeout& onTimeout)
 {
   return this->expressInterest(
     interest,
     [onData] (const Interest& interest, const Data& data) {
       if (onData != nullptr) {
         onData(interest, const_cast<Data&>(data));
       }
     },
     [onTimeout] (const Interest& interest, const lp::Nack& nack) {
       if (onTimeout != nullptr) {
         onTimeout(interest);
       }
     },
     onTimeout
   );
 }

 const PendingInterestId*
 Face::expressInterest(const Name& name, const Interest& tmpl,
                       const OnData& onData, const OnTimeout& onTimeout)
 {
   return expressInterest(Interest(tmpl).setName(name).setNonce(0),
                          onData, onTimeout);
 }

 void
 Face::removePendingInterest(const PendingInterestId* pendingInterestId)
 {
   IO_CAPTURE_WEAK_IMPL(post) {
     impl->asyncRemovePendingInterest(pendingInterestId);
   } IO_CAPTURE_WEAK_IMPL_END
 }

 void
 Face::removeAllPendingInterests()
 {
   IO_CAPTURE_WEAK_IMPL(post) {
     impl->asyncRemoveAllPendingInterests();
   } IO_CAPTURE_WEAK_IMPL_END
 }

 size_t
 Face::getNPendingInterests() const
 {
   return m_impl->m_pendingInterestTable.size();
 }

 void
 Face::put(const Data& data)
 {
   Block wire = data.wireEncode();

   shared_ptr<lp::CachePolicyTag> cachePolicyTag = data.getTag<lp::CachePolicyTag>();
   if (cachePolicyTag != nullptr) {
     lp::Packet packet;
     packet.add<lp::CachePolicyField>(*cachePolicyTag);
     packet.add<lp::FragmentField>(std::make_pair(wire.begin(), wire.end()));
     wire = packet.wireEncode();
   }

   if (wire.size() > MAX_NDN_PACKET_SIZE)
     BOOST_THROW_EXCEPTION(Error("Data size exceeds maximum limit"));

   IO_CAPTURE_WEAK_IMPL(dispatch) {
     impl->asyncSend(wire);
   } IO_CAPTURE_WEAK_IMPL_END
 }

 void
 Face::put(const lp::Nack& nack)
 {
   lp::Packet packet;
   packet.add<lp::NackField>(nack.getHeader());
   const Block& interestWire = nack.getInterest().wireEncode();
   packet.add<lp::FragmentField>(std::make_pair(interestWire.begin(), interestWire.end()));

   Block wire = packet.wireEncode();

   if (wire.size() > MAX_NDN_PACKET_SIZE)
     BOOST_THROW_EXCEPTION(Error("Nack size exceeds maximum limit"));

   IO_CAPTURE_WEAK_IMPL(dispatch) {
     impl->asyncSend(wire);
   } IO_CAPTURE_WEAK_IMPL_END
 }

 const RegisteredPrefixId*
 Face::setInterestFilter(const InterestFilter& interestFilter,
                         const InterestCallback& onInterest,
                         const RegisterPrefixFailureCallback& onFailure,
                         const security::SigningInfo& signingInfo,
                         uint64_t flags)
 {
   return setInterestFilter(interestFilter, onInterest, nullptr, onFailure, signingInfo, flags);
 }

 const RegisteredPrefixId*
 Face::setInterestFilter(const InterestFilter& interestFilter,
                         const InterestCallback& onInterest,
                         const RegisterPrefixSuccessCallback& onSuccess,
                         const RegisterPrefixFailureCallback& onFailure,
                         const security::SigningInfo& signingInfo,
                         uint64_t flags)
 {
   auto filter = make_shared<InterestFilterRecord>(interestFilter, onInterest);

   nfd::CommandOptions options;
   options.setSigningInfo(signingInfo);

   return m_impl->registerPrefix(interestFilter.getPrefix(), filter,
                                 onSuccess, onFailure, flags, options);
 }

 const InterestFilterId*
 Face::setInterestFilter(const InterestFilter& interestFilter,
                         const InterestCallback& onInterest)
 {
   auto filter = make_shared<InterestFilterRecord>(interestFilter, onInterest);

   IO_CAPTURE_WEAK_IMPL(post) {
     impl->asyncSetInterestFilter(filter);
   } IO_CAPTURE_WEAK_IMPL_END

   return reinterpret_cast<const InterestFilterId*>(filter.get());
 }

 #ifdef NDN_FACE_KEEP_DEPRECATED_REGISTRATION_SIGNING

 const RegisteredPrefixId*
 Face::setInterestFilter(const InterestFilter& interestFilter,
                         const OnInterest& onInterest,
                         const RegisterPrefixSuccessCallback& onSuccess,
                         const RegisterPrefixFailureCallback& onFailure,
                         const IdentityCertificate& certificate,
                         uint64_t flags)
 {
   security::SigningInfo signingInfo;
   if (!certificate.getName().empty()) {
     signingInfo = signingByCertificate(certificate.getName());
   }
   return setInterestFilter(interestFilter, onInterest, onSuccess, onFailure, signingInfo, flags);
 }

 const RegisteredPrefixId*
 Face::setInterestFilter(const InterestFilter& interestFilter,
                         const OnInterest& onInterest,
                         const RegisterPrefixFailureCallback& onFailure,
                         const IdentityCertificate& certificate,
                         uint64_t flags)
 {
   security::SigningInfo signingInfo;
   if (!certificate.getName().empty()) {
     signingInfo = signingByCertificate(certificate.getName());
   }
   return setInterestFilter(interestFilter, onInterest, onFailure, signingInfo, flags);
 }

 const RegisteredPrefixId*
 Face::setInterestFilter(const InterestFilter& interestFilter,
                         const OnInterest& onInterest,
                         const RegisterPrefixSuccessCallback& onSuccess,
                         const RegisterPrefixFailureCallback& onFailure,
                         const Name& identity,
                         uint64_t flags)
 {
   security::SigningInfo signingInfo = signingByIdentity(identity);
   return setInterestFilter(interestFilter, onInterest,
                            onSuccess, onFailure,
                            signingInfo, flags);
 }

 const RegisteredPrefixId*
 Face::setInterestFilter(const InterestFilter& interestFilter,
                         const OnInterest& onInterest,
                         const RegisterPrefixFailureCallback& onFailure,
                         const Name& identity,
                         uint64_t flags)
 {
   security::SigningInfo signingInfo = signingByIdentity(identity);
   return setInterestFilter(interestFilter, onInterest, onFailure, signingInfo, flags);
 }

 #endif // NDN_FACE_KEEP_DEPRECATED_REGISTRATION_SIGNING

 const RegisteredPrefixId*
 Face::registerPrefix(const Name& prefix,
                      const RegisterPrefixSuccessCallback& onSuccess,
                      const RegisterPrefixFailureCallback& onFailure,
                      const security::SigningInfo& signingInfo,
                      uint64_t flags)
 {
   nfd::CommandOptions options;
   options.setSigningInfo(signingInfo);

   return m_impl->registerPrefix(prefix, nullptr, onSuccess, onFailure, flags, options);
 }

 #ifdef NDN_FACE_KEEP_DEPRECATED_REGISTRATION_SIGNING
 const RegisteredPrefixId*
 Face::registerPrefix(const Name& prefix,
                      const RegisterPrefixSuccessCallback& onSuccess,
                      const RegisterPrefixFailureCallback& onFailure,
                      const IdentityCertificate& certificate,
                      uint64_t flags)
 {
   security::SigningInfo signingInfo;
   if (!certificate.getName().empty()) {
     signingInfo = signingByCertificate(certificate.getName());
   }
   return registerPrefix(prefix, onSuccess, onFailure, signingInfo, flags);
 }

 const RegisteredPrefixId*
 Face::registerPrefix(const Name& prefix,
                      const RegisterPrefixSuccessCallback& onSuccess,
                      const RegisterPrefixFailureCallback& onFailure,
                      const Name& identity,
                      uint64_t flags)
 {
   security::SigningInfo signingInfo = signingByIdentity(identity);
   return registerPrefix(prefix, onSuccess, onFailure, signingInfo, flags);
 }
 #endif // NDN_FACE_KEEP_DEPRECATED_REGISTRATION_SIGNING

 void
 Face::unsetInterestFilter(const RegisteredPrefixId* registeredPrefixId)
 {
   IO_CAPTURE_WEAK_IMPL(post) {
     impl->asyncUnregisterPrefix(registeredPrefixId, nullptr, nullptr);
   } IO_CAPTURE_WEAK_IMPL_END
 }

 void
 Face::unsetInterestFilter(const InterestFilterId* interestFilterId)
 {
   IO_CAPTURE_WEAK_IMPL(post) {
     impl->asyncUnsetInterestFilter(interestFilterId);
   } IO_CAPTURE_WEAK_IMPL_END
 }

 void
 Face::unregisterPrefix(const RegisteredPrefixId* registeredPrefixId,
                        const UnregisterPrefixSuccessCallback& onSuccess,
                        const UnregisterPrefixFailureCallback& onFailure)
 {
   IO_CAPTURE_WEAK_IMPL(post) {
     impl->asyncUnregisterPrefix(registeredPrefixId, onSuccess, onFailure);
   } IO_CAPTURE_WEAK_IMPL_END
 }

 void
 Face::processEvents(const time::milliseconds& timeout, bool keepThread)
 {
   if (m_ioService.stopped()) {
     m_ioService.reset(); // ensure that run()/poll() will do some work
   }

   try {
     if (timeout < time::milliseconds::zero()) {
       // do not block if timeout is negative, but process pending events
       m_ioService.poll();
       return;
     }

     if (timeout > time::milliseconds::zero()) {
       boost::asio::io_service& ioService = m_ioService;
       unique_ptr<boost::asio::io_service::work>& work = m_impl->m_ioServiceWork;
       m_impl->m_processEventsTimeoutEvent = m_impl->m_scheduler.scheduleEvent(timeout,
         [&ioService, &work] {
           ioService.stop();
           work.reset();
         });
     }

     if (keepThread) {
       // work will ensure that m_ioService is running until work object exists
       m_impl->m_ioServiceWork.reset(new boost::asio::io_service::work(m_ioService));
     }

     m_ioService.run();
   }
   catch (...) {
     m_impl->m_ioServiceWork.reset();
     m_impl->m_pendingInterestTable.clear();
     m_impl->m_registeredPrefixTable.clear();
     throw;
   }
 }

 void
 Face::shutdown()
 {
   IO_CAPTURE_WEAK_IMPL(post) {
     this->asyncShutdown();
   } IO_CAPTURE_WEAK_IMPL_END
 }

 void
 Face::asyncShutdown()
 {
   m_impl->m_pendingInterestTable.clear();
   m_impl->m_registeredPrefixTable.clear();

   if (m_transport->isConnected())
     m_transport->close();

   m_impl->m_ioServiceWork.reset();
 }

 /**
  * @brief extract local fields from NDNLPv2 packet and tag onto a network layer packet
  */
 template<typename NETPKT>
 static void
 extractLpLocalFields(NETPKT& netPacket, const lp::Packet& lpPacket)
 {
   if (lpPacket.has<lp::IncomingFaceIdField>()) {
     netPacket.setTag(make_shared<lp::IncomingFaceIdTag>(lpPacket.get<lp::IncomingFaceIdField>()));
   }
 }

 void
 Face::onReceiveElement(const Block& blockFromDaemon)
 {
   lp::Packet lpPacket(blockFromDaemon); // bare Interest/Data is a valid lp::Packet,
                                         // no need to distinguish

   Buffer::const_iterator begin, end;
   std::tie(begin, end) = lpPacket.get<lp::FragmentField>();
   Block netPacket(&*begin, std::distance(begin, end));
   switch (netPacket.type()) {
     case tlv::Interest: {
       auto interest = make_shared<Interest>(netPacket);
       if (lpPacket.has<lp::NackField>()) {
         auto nack = make_shared<lp::Nack>(std::move(*interest));
         nack->setHeader(lpPacket.get<lp::NackField>());
         extractLpLocalFields(*nack, lpPacket);
         m_impl->nackPendingInterests(*nack);
       }
       else {
         extractLpLocalFields(*interest, lpPacket);
         m_impl->processInterestFilters(*interest);
       }
       break;
     }
     case tlv::Data: {
       auto data = make_shared<Data>(netPacket);
       extractLpLocalFields(*data, lpPacket);
       m_impl->satisfyPendingInterests(*data);
       break;
     }
   }
 }

 } // namespace ndn
	/* -- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -- */
	/**
	* Copyright (c) 2013-2016 Regents of the University of California.
	*
	* This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
	*
	* ndn-cxx library is free software: you can redistribute it and/or modify it under the
	* terms of the GNU Lesser General Public License as published by the Free Software
	* Foundation, either version 3 of the License, or (at your option) any later version.
	*
	* ndn-cxx library 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 Lesser General Public License for more details.
	*
	* You should have received copies of the GNU General Public License and GNU Lesser
	* General Public License along with ndn-cxx, e.g., in COPYING.md file. If not, see
	* <http://www.gnu.org/licenses/>.
	*
	* See AUTHORS.md for complete list of ndn-cxx authors and contributors.
	*/

	#include "face.hpp"
	#include "detail/face-impl.hpp"

	#include "encoding/tlv.hpp"
	#include "security/key-chain.hpp"
	#include "security/signing-helpers.hpp"
	#include "util/time.hpp"
	#include "util/random.hpp"
	#include "util/face-uri.hpp"

	// A callback scheduled through io.post and io.dispatch may be invoked after the face
	// is destructed. To prevent this situation, these macros captures Face::m_impl as weak_ptr,
	// and skips callback execution if the face has been destructed.
	#define IO_CAPTURE_WEAK_IMPL(OP) \
	{ \
	weak_ptr<Impl> implWeak(m_impl); \
	m_ioService.OP([=] { \
	auto impl = implWeak.lock(); \
	if (impl != nullptr) {
	#define IO_CAPTURE_WEAK_IMPL_END \
	} \
	}); \
	}

	namespace ndn {

	Face::Face(shared_ptr<Transport> transport)
	: m_internalIoService(new boost::asio::io_service())
	, m_ioService(*m_internalIoService)
	, m_internalKeyChain(new KeyChain())
	, m_impl(make_shared<Impl>(*this))
	{
	construct(transport, *m_internalKeyChain);
	}

	Face::Face(boost::asio::io_service& ioService)
	: m_ioService(ioService)
	, m_internalKeyChain(new KeyChain())
	, m_impl(make_shared<Impl>(*this))
	{
	construct(nullptr, *m_internalKeyChain);
	}

	Face::Face(const std::string& host, const std::string& port)
	: m_internalIoService(new boost::asio::io_service())
	, m_ioService(*m_internalIoService)
	, m_internalKeyChain(new KeyChain())
	, m_impl(make_shared<Impl>(*this))
	{
	construct(make_shared<TcpTransport>(host, port), *m_internalKeyChain);
	}

	Face::Face(shared_ptr<Transport> transport, KeyChain& keyChain)
	: m_internalIoService(new boost::asio::io_service())
	, m_ioService(*m_internalIoService)
	, m_impl(make_shared<Impl>(*this))
	{
	construct(transport, keyChain);
	}

	Face::Face(shared_ptr<Transport> transport, boost::asio::io_service& ioService)
	: m_ioService(ioService)
	, m_internalKeyChain(new KeyChain())
	, m_impl(make_shared<Impl>(*this))
	{
	construct(transport, *m_internalKeyChain);
	}

	Face::Face(shared_ptr<Transport> transport, boost::asio::io_service& ioService, KeyChain& keyChain)
	: m_ioService(ioService)
	, m_impl(make_shared<Impl>(*this))
	{
	construct(transport, keyChain);
	}

	shared_ptr<Transport>
	Face::makeDefaultTransport()
	{
	// transport=unix:///var/run/nfd.sock
	// transport=tcp://localhost:6363

	std::string transportUri;

	const char* transportEnviron = getenv("NDN_CLIENT_TRANSPORT");
	if (transportEnviron != nullptr) {
	transportUri = transportEnviron;
	}
	else {
	ConfigFile config;
	transportUri = config.getParsedConfiguration().get<std::string>("transport", "");
	}

	if (transportUri.empty()) {
	// transport not specified, use default Unix transport.
	return UnixTransport::create("");
	}

	std::string protocol;
	try {
	util::FaceUri uri(transportUri);
	protocol = uri.getScheme();

	if (protocol == "unix") {
	return UnixTransport::create(transportUri);
	}
	else if (protocol == "tcp" \|\| protocol == "tcp4" \|\| protocol == "tcp6") {
	return TcpTransport::create(transportUri);
	}
	else {
	BOOST_THROW_EXCEPTION(ConfigFile::Error("Unsupported transport protocol \"" + protocol + "\""));
	}
	}
	catch (const Transport::Error& error) {
	BOOST_THROW_EXCEPTION(ConfigFile::Error(error.what()));
	}
	catch (const util::FaceUri::Error& error) {
	BOOST_THROW_EXCEPTION(ConfigFile::Error(error.what()));
	}
	}

	void
	Face::construct(shared_ptr<Transport> transport, KeyChain& keyChain)
	{
	if (transport == nullptr) {
	transport = makeDefaultTransport();
	}
	BOOST_ASSERT(transport != nullptr);
	m_transport = transport;

	m_nfdController.reset(new nfd::Controller(*this, keyChain));

	IO_CAPTURE_WEAK_IMPL(post) {
	impl->ensureConnected(false);
	} IO_CAPTURE_WEAK_IMPL_END
	}

	Face::~Face() = default;

	shared_ptr<Transport>
	Face::getTransport()
	{
	return m_transport;
	}

	const PendingInterestId*
	Face::expressInterest(const Interest& interest,
	const DataCallback& afterSatisfied,
	const NackCallback& afterNacked,
	const TimeoutCallback& afterTimeout)
	{
	shared_ptr<Interest> interestToExpress = make_shared<Interest>(interest);

	// Use `interestToExpress` to avoid wire format creation for the original Interest
	if (interestToExpress->wireEncode().size() > MAX_NDN_PACKET_SIZE) {
	BOOST_THROW_EXCEPTION(Error("Interest size exceeds maximum limit"));
	}

	// If the same ioService thread, dispatch directly calls the method
	IO_CAPTURE_WEAK_IMPL(dispatch) {
	impl->asyncExpressInterest(interestToExpress, afterSatisfied, afterNacked, afterTimeout);
	} IO_CAPTURE_WEAK_IMPL_END

	return reinterpret_cast<const PendingInterestId*>(interestToExpress.get());
	}

	const PendingInterestId*
	Face::expressInterest(const Interest& interest,
	const OnData& onData,
	const OnTimeout& onTimeout)
	{
	return this->expressInterest(
	interest,
	[onData] (const Interest& interest, const Data& data) {
	if (onData != nullptr) {
	onData(interest, const_cast<Data&>(data));
	}
	},
	[onTimeout] (const Interest& interest, const lp::Nack& nack) {
	if (onTimeout != nullptr) {
	onTimeout(interest);
	}
	},
	onTimeout
	);
	}

	const PendingInterestId*
	Face::expressInterest(const Name& name, const Interest& tmpl,
	const OnData& onData, const OnTimeout& onTimeout)
	{
	return expressInterest(Interest(tmpl).setName(name).setNonce(0),
	onData, onTimeout);
	}

	void
	Face::removePendingInterest(const PendingInterestId* pendingInterestId)
	{
	IO_CAPTURE_WEAK_IMPL(post) {
	impl->asyncRemovePendingInterest(pendingInterestId);
	} IO_CAPTURE_WEAK_IMPL_END
	}

	void
	Face::removeAllPendingInterests()
	{
	IO_CAPTURE_WEAK_IMPL(post) {
	impl->asyncRemoveAllPendingInterests();
	} IO_CAPTURE_WEAK_IMPL_END
	}

	size_t
	Face::getNPendingInterests() const
	{
	return m_impl->m_pendingInterestTable.size();
	}

	void
	Face::put(const Data& data)
	{
	Block wire = data.wireEncode();

	shared_ptr<lp::CachePolicyTag> cachePolicyTag = data.getTag<lp::CachePolicyTag>();
	if (cachePolicyTag != nullptr) {
	lp::Packet packet;
	packet.add<lp::CachePolicyField>(*cachePolicyTag);
	packet.add<lp::FragmentField>(std::make_pair(wire.begin(), wire.end()));
	wire = packet.wireEncode();
	}

	if (wire.size() > MAX_NDN_PACKET_SIZE)
	BOOST_THROW_EXCEPTION(Error("Data size exceeds maximum limit"));

	IO_CAPTURE_WEAK_IMPL(dispatch) {
	impl->asyncSend(wire);
	} IO_CAPTURE_WEAK_IMPL_END
	}

	void
	Face::put(const lp::Nack& nack)
	{
	lp::Packet packet;
	packet.add<lp::NackField>(nack.getHeader());
	const Block& interestWire = nack.getInterest().wireEncode();
	packet.add<lp::FragmentField>(std::make_pair(interestWire.begin(), interestWire.end()));

	Block wire = packet.wireEncode();

	if (wire.size() > MAX_NDN_PACKET_SIZE)
	BOOST_THROW_EXCEPTION(Error("Nack size exceeds maximum limit"));

	IO_CAPTURE_WEAK_IMPL(dispatch) {
	impl->asyncSend(wire);
	} IO_CAPTURE_WEAK_IMPL_END
	}

	const RegisteredPrefixId*
	Face::setInterestFilter(const InterestFilter& interestFilter,
	const InterestCallback& onInterest,
	const RegisterPrefixFailureCallback& onFailure,
	const security::SigningInfo& signingInfo,
	uint64_t flags)
	{
	return setInterestFilter(interestFilter, onInterest, nullptr, onFailure, signingInfo, flags);
	}

	const RegisteredPrefixId*
	Face::setInterestFilter(const InterestFilter& interestFilter,
	const InterestCallback& onInterest,
	const RegisterPrefixSuccessCallback& onSuccess,
	const RegisterPrefixFailureCallback& onFailure,
	const security::SigningInfo& signingInfo,
	uint64_t flags)
	{
	auto filter = make_shared<InterestFilterRecord>(interestFilter, onInterest);

	nfd::CommandOptions options;
	options.setSigningInfo(signingInfo);

	return m_impl->registerPrefix(interestFilter.getPrefix(), filter,
	onSuccess, onFailure, flags, options);
	}

	const InterestFilterId*
	Face::setInterestFilter(const InterestFilter& interestFilter,
	const InterestCallback& onInterest)
	{
	auto filter = make_shared<InterestFilterRecord>(interestFilter, onInterest);

	IO_CAPTURE_WEAK_IMPL(post) {
	impl->asyncSetInterestFilter(filter);
	} IO_CAPTURE_WEAK_IMPL_END

	return reinterpret_cast<const InterestFilterId*>(filter.get());
	}

	#ifdef NDN_FACE_KEEP_DEPRECATED_REGISTRATION_SIGNING

	const RegisteredPrefixId*
	Face::setInterestFilter(const InterestFilter& interestFilter,
	const OnInterest& onInterest,
	const RegisterPrefixSuccessCallback& onSuccess,
	const RegisterPrefixFailureCallback& onFailure,
	const IdentityCertificate& certificate,
	uint64_t flags)
	{
	security::SigningInfo signingInfo;
	if (!certificate.getName().empty()) {
	signingInfo = signingByCertificate(certificate.getName());
	}
	return setInterestFilter(interestFilter, onInterest, onSuccess, onFailure, signingInfo, flags);
	}

	const RegisteredPrefixId*
	Face::setInterestFilter(const InterestFilter& interestFilter,
	const OnInterest& onInterest,
	const RegisterPrefixFailureCallback& onFailure,
	const IdentityCertificate& certificate,
	uint64_t flags)
	{
	security::SigningInfo signingInfo;
	if (!certificate.getName().empty()) {
	signingInfo = signingByCertificate(certificate.getName());
	}
	return setInterestFilter(interestFilter, onInterest, onFailure, signingInfo, flags);
	}

	const RegisteredPrefixId*
	Face::setInterestFilter(const InterestFilter& interestFilter,
	const OnInterest& onInterest,
	const RegisterPrefixSuccessCallback& onSuccess,
	const RegisterPrefixFailureCallback& onFailure,
	const Name& identity,
	uint64_t flags)
	{
	security::SigningInfo signingInfo = signingByIdentity(identity);
	return setInterestFilter(interestFilter, onInterest,
	onSuccess, onFailure,
	signingInfo, flags);
	}

	const RegisteredPrefixId*
	Face::setInterestFilter(const InterestFilter& interestFilter,
	const OnInterest& onInterest,
	const RegisterPrefixFailureCallback& onFailure,
	const Name& identity,
	uint64_t flags)
	{
	security::SigningInfo signingInfo = signingByIdentity(identity);
	return setInterestFilter(interestFilter, onInterest, onFailure, signingInfo, flags);
	}

	#endif // NDN_FACE_KEEP_DEPRECATED_REGISTRATION_SIGNING

	const RegisteredPrefixId*
	Face::registerPrefix(const Name& prefix,
	const RegisterPrefixSuccessCallback& onSuccess,
	const RegisterPrefixFailureCallback& onFailure,
	const security::SigningInfo& signingInfo,
	uint64_t flags)
	{
	nfd::CommandOptions options;
	options.setSigningInfo(signingInfo);

	return m_impl->registerPrefix(prefix, nullptr, onSuccess, onFailure, flags, options);
	}

	#ifdef NDN_FACE_KEEP_DEPRECATED_REGISTRATION_SIGNING
	const RegisteredPrefixId*
	Face::registerPrefix(const Name& prefix,
	const RegisterPrefixSuccessCallback& onSuccess,
	const RegisterPrefixFailureCallback& onFailure,
	const IdentityCertificate& certificate,
	uint64_t flags)
	{
	security::SigningInfo signingInfo;
	if (!certificate.getName().empty()) {
	signingInfo = signingByCertificate(certificate.getName());
	}
	return registerPrefix(prefix, onSuccess, onFailure, signingInfo, flags);
	}

	const RegisteredPrefixId*
	Face::registerPrefix(const Name& prefix,
	const RegisterPrefixSuccessCallback& onSuccess,
	const RegisterPrefixFailureCallback& onFailure,
	const Name& identity,
	uint64_t flags)
	{
	security::SigningInfo signingInfo = signingByIdentity(identity);
	return registerPrefix(prefix, onSuccess, onFailure, signingInfo, flags);
	}
	#endif // NDN_FACE_KEEP_DEPRECATED_REGISTRATION_SIGNING

	void
	Face::unsetInterestFilter(const RegisteredPrefixId* registeredPrefixId)
	{
	IO_CAPTURE_WEAK_IMPL(post) {
	impl->asyncUnregisterPrefix(registeredPrefixId, nullptr, nullptr);
	} IO_CAPTURE_WEAK_IMPL_END
	}

	void
	Face::unsetInterestFilter(const InterestFilterId* interestFilterId)
	{
	IO_CAPTURE_WEAK_IMPL(post) {
	impl->asyncUnsetInterestFilter(interestFilterId);
	} IO_CAPTURE_WEAK_IMPL_END
	}

	void
	Face::unregisterPrefix(const RegisteredPrefixId* registeredPrefixId,
	const UnregisterPrefixSuccessCallback& onSuccess,
	const UnregisterPrefixFailureCallback& onFailure)
	{
	IO_CAPTURE_WEAK_IMPL(post) {
	impl->asyncUnregisterPrefix(registeredPrefixId, onSuccess, onFailure);
	} IO_CAPTURE_WEAK_IMPL_END
	}

	void
	Face::processEvents(const time::milliseconds& timeout, bool keepThread)
	{
	if (m_ioService.stopped()) {
	m_ioService.reset(); // ensure that run()/poll() will do some work
	}

	try {
	if (timeout < time::milliseconds::zero()) {
	// do not block if timeout is negative, but process pending events
	m_ioService.poll();
	return;
	}

	if (timeout > time::milliseconds::zero()) {
	boost::asio::io_service& ioService = m_ioService;
	unique_ptr<boost::asio::io_service::work>& work = m_impl->m_ioServiceWork;
	m_impl->m_processEventsTimeoutEvent = m_impl->m_scheduler.scheduleEvent(timeout,
	[&ioService, &work] {
	ioService.stop();
	work.reset();
	});
	}

	if (keepThread) {
	// work will ensure that m_ioService is running until work object exists
	m_impl->m_ioServiceWork.reset(new boost::asio::io_service::work(m_ioService));
	}

	m_ioService.run();
	}
	catch (...) {
	m_impl->m_ioServiceWork.reset();
	m_impl->m_pendingInterestTable.clear();
	m_impl->m_registeredPrefixTable.clear();
	throw;
	}
	}

	void
	Face::shutdown()
	{
	IO_CAPTURE_WEAK_IMPL(post) {
	this->asyncShutdown();
	} IO_CAPTURE_WEAK_IMPL_END
	}

	void
	Face::asyncShutdown()
	{
	m_impl->m_pendingInterestTable.clear();
	m_impl->m_registeredPrefixTable.clear();

	if (m_transport->isConnected())
	m_transport->close();

	m_impl->m_ioServiceWork.reset();
	}

	/**
	* @brief extract local fields from NDNLPv2 packet and tag onto a network layer packet
	*/
	template<typename NETPKT>
	static void
	extractLpLocalFields(NETPKT& netPacket, const lp::Packet& lpPacket)
	{
	if (lpPacket.has<lp::IncomingFaceIdField>()) {
	netPacket.setTag(make_shared<lp::IncomingFaceIdTag>(lpPacket.get<lp::IncomingFaceIdField>()));
	}
	}

	void
	Face::onReceiveElement(const Block& blockFromDaemon)
	{
	lp::Packet lpPacket(blockFromDaemon); // bare Interest/Data is a valid lp::Packet,
	// no need to distinguish

	Buffer::const_iterator begin, end;
	std::tie(begin, end) = lpPacket.get<lp::FragmentField>();
	Block netPacket(&*begin, std::distance(begin, end));
	switch (netPacket.type()) {
	case tlv::Interest: {
	auto interest = make_shared<Interest>(netPacket);
	if (lpPacket.has<lp::NackField>()) {
	auto nack = make_shared<lp::Nack>(std::move(*interest));
	nack->setHeader(lpPacket.get<lp::NackField>());
	extractLpLocalFields(*nack, lpPacket);
	m_impl->nackPendingInterests(*nack);
	}
	else {
	extractLpLocalFields(*interest, lpPacket);
	m_impl->processInterestFilters(*interest);
	}
	break;
	}
	case tlv::Data: {
	auto data = make_shared<Data>(netPacket);
	extractLpLocalFields(*data, lpPacket);
	m_impl->satisfyPendingInterests(*data);
	break;
	}
	}
	}

	} // namespace ndn