src/node.cpp - ndn-cxx - Gitiles

 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
 /**
  * Copyright (C) 2013 Regents of the University of California.
  * @author: Jeff Thompson <jefft0@remap.ucla.edu>
  * See COPYING for copyright and distribution information.
  */

 #include <stdexcept>
 #include "c/util/time.h"

 #include <ndn-cpp/forwarding-entry.hpp>
 #include <ndn-cpp/face-instance.hpp>
 #include <ndn-cpp/node.hpp>

 #include "util/ndnd-id-fetcher.hpp"

 #include <ndn-cpp/security/signature-sha256-with-rsa.hpp>
 #include <ndn-cpp/status-response.hpp>

 using namespace std;
 #if NDN_CPP_HAVE_CXX11
 // In the std library, the placeholders are in a different namespace than boost.
 using namespace ndn::func_lib::placeholders;
 #endif

 namespace ndn {

 uint64_t Node::PendingInterest::lastPendingInterestId_ = 0;
 uint64_t Node::RegisteredPrefix::lastRegisteredPrefixId_ = 0;

 Node::Node(const ptr_lib::shared_ptr<Transport>& transport)
   : pitTimeoutCheckTimerActive_(false)
   , transport_(transport)
   , ndndIdFetcherInterest_(Name("/%C1.M.S.localhost/%C1.M.SRV/ndnd/KEY"), 4000.0)
 {
   ioService_ = ptr_lib::make_shared<boost::asio::io_service>();
   pitTimeoutCheckTimer_      = ptr_lib::make_shared<boost::asio::deadline_timer>(boost::ref(*ioService_));
   processEventsTimeoutTimer_ = ptr_lib::make_shared<boost::asio::deadline_timer>(boost::ref(*ioService_));
 }

 Node::Node(const ptr_lib::shared_ptr<Transport>& transport, const ptr_lib::shared_ptr<boost::asio::io_service> &ioService)
   : ioService_(ioService)
   , pitTimeoutCheckTimerActive_(false)
   , transport_(transport)
   , ndndIdFetcherInterest_(Name("/%C1.M.S.localhost/%C1.M.SRV/ndnd/KEY"), 4000.0)
 {
   pitTimeoutCheckTimer_      = ptr_lib::make_shared<boost::asio::deadline_timer>(boost::ref(*ioService_));
   processEventsTimeoutTimer_ = ptr_lib::make_shared<boost::asio::deadline_timer>(boost::ref(*ioService_));
 }

 uint64_t
 Node::expressInterest(const Interest& interest, const OnData& onData, const OnTimeout& onTimeout)
 {
   if (!transport_->isConnected())
     transport_->connect(*ioService_,
                         ptr_lib::bind(&Node::onReceiveElement, this, _1));

   uint64_t pendingInterestId = PendingInterest::getNextPendingInterestId();
   pendingInterestTable_.push_back(ptr_lib::shared_ptr<PendingInterest>(new PendingInterest
     (pendingInterestId, ptr_lib::shared_ptr<const Interest>(new Interest(interest)), onData, onTimeout)));

   transport_->send(interest.wireEncode());

   if (!pitTimeoutCheckTimerActive_) {
     pitTimeoutCheckTimerActive_ = true;
     pitTimeoutCheckTimer_->expires_from_now(boost::posix_time::milliseconds(100));
     pitTimeoutCheckTimer_->async_wait(func_lib::bind(&Node::checkPitExpire, this));
   }

   return pendingInterestId;
 }

 void
 Node::put(const Data &data)
 {
   if (!transport_->isConnected())
     transport_->connect(*ioService_,
                         ptr_lib::bind(&Node::onReceiveElement, this, _1));

   transport_->send(data.wireEncode());
 }


 void
 Node::removePendingInterest(uint64_t pendingInterestId)
 {
   // Go backwards through the list so we can erase entries.
   // Remove all entries even though pendingInterestId should be unique.
   for (int i = (int)pendingInterestTable_.size() - 1; i >= 0; --i) {
     if (pendingInterestTable_[i]->getPendingInterestId() == pendingInterestId)
       pendingInterestTable_.erase(pendingInterestTable_.begin() + i);
   }
 }

 uint64_t
 Node::registerPrefix
   (const Name& prefix, const OnInterest& onInterest, const OnRegisterFailed& onRegisterFailed, const ForwardingFlags& flags)
 {
   // Get the registeredPrefixId now so we can return it to the caller.
   uint64_t registeredPrefixId = RegisteredPrefix::getNextRegisteredPrefixId();
   ptr_lib::shared_ptr<const Name> prefixPtr = ptr_lib::make_shared<const Name>(prefix);

   if (ndndId_.size() == 0) {
     // First fetch the ndndId of the connected hub.
     NdndIdFetcher fetcher(ndndId_,
                           func_lib::bind(&Node::registerPrefixHelper, this,
                                          registeredPrefixId, prefixPtr, onInterest, onRegisterFailed, flags),
                           func_lib::bind(onRegisterFailed, prefixPtr));

     // @todo: Check if this crash
     // It is OK for func_lib::function make a copy of the function object because the Info is in a ptr_lib::shared_ptr.
     expressInterest(ndndIdFetcherInterest_, fetcher, fetcher);
   }
   else
     registerPrefixHelper(registeredPrefixId, prefixPtr, onInterest, onRegisterFailed, flags);

   return registeredPrefixId;
 }

 void
 Node::removeRegisteredPrefix(uint64_t registeredPrefixId)
 {
   // Go backwards through the list so we can erase entries.
   // Remove all entries even though pendingInterestId should be unique.

   for (RegisteredPrefixTable::iterator i = registeredPrefixTable_.begin();
        i != registeredPrefixTable_.end();
        ++i)
     {
       if ((*i)->getRegisteredPrefixId() == registeredPrefixId) {
         ForwardingEntry forwardingEntry("unreg", *(*i)->getPrefix(), faceId_);
         Data data;
         data.setContent(forwardingEntry.wireEncode());

         SignatureSha256WithRsa signature;
         signature.setValue(Block(Tlv::SignatureValue, ptr_lib::make_shared<Buffer>()));
         data.setSignature(signature);

         // Create an interest where the name has the encoded Data packet.
         Name interestName;
         interestName.append("ndnx");
         interestName.append(ndndId_);
         interestName.append("unreg");
         interestName.append(data.wireEncode());

         Interest interest(interestName);
         interest.setScope(1);
         interest.setInterestLifetime(1000);

         expressInterest(interest, OnData(), OnTimeout());

         registeredPrefixTable_.erase(i);
         break;
       }
     }
 }

 void
 Node::registerPrefixHelper(uint64_t registeredPrefixId,
                            const ptr_lib::shared_ptr<const Name>& prefix,
                            const OnInterest& onInterest,
                            const OnRegisterFailed& onRegisterFailed,
                            const ForwardingFlags& flags)
 {
   // Create a ForwardingEntry.

   // AlexA: ndnd ignores any freshness that is larger than 3600 sec and sets 300 sec instead
   //        to register "forever" (=2000000000 sec), freshnessPeriod must be omitted
   ForwardingEntry forwardingEntry("selfreg", *prefix, -1, flags, -1);
   Block content = forwardingEntry.wireEncode();

   // Set the ForwardingEntry as the content of a Data packet and sign.
   Data data;
   data.setContent(content);

   // Create an empty signature, since nobody going to verify it for now
   // @todo In the future, we may require real signatures to do the registration
   SignatureSha256WithRsa signature;
   signature.setValue(Block(Tlv::SignatureValue, ptr_lib::make_shared<Buffer>()));
   data.setSignature(signature);

   // Create an interest where the name has the encoded Data packet.
   Name interestName;
   interestName.append("ndnx");
   interestName.append(ndndId_);
   interestName.append("selfreg");
   interestName.append(data.wireEncode());

   Interest interest(interestName);
   interest.setScope(1);
   interest.setInterestLifetime(1000);

   expressInterest(interest,
                   func_lib::bind(&Node::registerPrefixFinal, this,
                                  registeredPrefixId, prefix, onInterest, onRegisterFailed, _1, _2),
                   func_lib::bind(onRegisterFailed, prefix));
 }

 void
 Node::registerPrefixFinal(uint64_t registeredPrefixId,
                           const ptr_lib::shared_ptr<const Name>& prefix,
                           const OnInterest& onInterest,
                           const OnRegisterFailed& onRegisterFailed,
                           const ptr_lib::shared_ptr<const Interest>&, const ptr_lib::shared_ptr<Data>&data)
 {
   Block content = data->getContent();
   content.parse();

   if (content.getAll().empty())
     {
       onRegisterFailed(prefix);
       return;
     }

   Block::element_iterator val = content.getAll().begin();

   switch(val->type())
     {
     case Tlv::FaceManagement::ForwardingEntry:
       {
         ForwardingEntry entry;
         entry.wireDecode(*val);

         // Save the onInterest callback and send the registration interest.
         registeredPrefixTable_.push_back(ptr_lib::make_shared<RegisteredPrefix>(registeredPrefixId, prefix, onInterest));

         /// @todo Notify user about successful registration

         // succeeded
         return;
       }
     case Tlv::FaceManagement::StatusResponse:
       {
         // failed :(
         StatusResponse resp;
         resp.wireDecode(*val);

         // std::cerr << "StatusReponse: " << resp << std::endl;

         onRegisterFailed(prefix);
         return;
       }
     default:
       {
         // failed :(

         onRegisterFailed(prefix);
         return;
       }
     }
 }

 void
 Node::processEvents(Milliseconds timeout/* = 0 */, bool keepThread/* = false*/)
 {
   try
     {
       if (timeout < 0)
         {
           // do not block if timeout is negative, but process pending events
           ioService_->poll();
           return;
         }

       if (timeout > 0)
         {
           processEventsTimeoutTimer_->expires_from_now(boost::posix_time::milliseconds(timeout));
           processEventsTimeoutTimer_->async_wait(fireProcessEventsTimeout);
         }

       if (keepThread) {
         // work will ensure that ioService_ is running until work object exists
         ioServiceWork_ = ptr_lib::make_shared<boost::asio::io_service::work>(boost::ref(*ioService_));
       }

       ioService_->run();
     }
   catch(Node::ProcessEventsTimeout &)
     {
       // break
       ioService_->reset();
     }
 }

 void
 Node::fireProcessEventsTimeout(const boost::system::error_code& error)
 {
   if (!error) // can fire for some other reason, e.g., cancelled
     throw Node::ProcessEventsTimeout();
 }

 void
 Node::checkPitExpire()
 {
   // Check for PIT entry timeouts.  Go backwards through the list so we can erase entries.
   MillisecondsSince1970 nowMilliseconds = ndn_getNowMilliseconds();
   for (int i = (int)pendingInterestTable_.size() - 1; i >= 0; --i) {
     if (pendingInterestTable_[i]->isTimedOut(nowMilliseconds)) {
       // Save the PendingInterest and remove it from the PIT.  Then call the callback.
       ptr_lib::shared_ptr<PendingInterest> pendingInterest = pendingInterestTable_[i];
       pendingInterestTable_.erase(pendingInterestTable_.begin() + i);
       pendingInterest->callTimeout();

       // Refresh now since the timeout callback might have delayed.
       nowMilliseconds = ndn_getNowMilliseconds();
     }
   }

   if (!pendingInterestTable_.empty()) {
     pitTimeoutCheckTimerActive_ = true;

     pitTimeoutCheckTimer_->expires_from_now(boost::posix_time::milliseconds(100));
     pitTimeoutCheckTimer_->async_wait(func_lib::bind(&Node::checkPitExpire, this));
   }
   else {
     pitTimeoutCheckTimerActive_ = false;

     if (registeredPrefixTable_.empty()) {
       transport_->close();
       if (!ioServiceWork_) {
         processEventsTimeoutTimer_->cancel();
       }
     }
   }
 }


 void
 Node::onReceiveElement(const Block &block)
 {
   if (block.type() == Tlv::Interest)
     {
       ptr_lib::shared_ptr<Interest> interest(new Interest());
       interest->wireDecode(block);

       RegisteredPrefixTable::iterator entry = getEntryForRegisteredPrefix(interest->getName());
       if (entry != registeredPrefixTable_.end()) {
         (*entry)->getOnInterest()((*entry)->getPrefix(), interest, *transport_, (*entry)->getRegisteredPrefixId());
       }
     }
   else if (block.type() == Tlv::Data)
     {
       ptr_lib::shared_ptr<Data> data(new Data());
       data->wireDecode(block);

       PendingInterestTable::iterator entry = getEntryIndexForExpressedInterest(data->getName());
       if (entry != pendingInterestTable_.end()) {
         // Copy pointers to the needed objects and remove the PIT entry before the calling the callback.
         const OnData onData = (*entry)->getOnData();
         const ptr_lib::shared_ptr<const Interest> interest = (*entry)->getInterest();
         pendingInterestTable_.erase(entry);

         if (onData) {
           onData(interest, data);
         }

         if (pendingInterestTable_.empty()) {
           pitTimeoutCheckTimer_->cancel(); // this will cause checkPitExpire invocation
         }
       }
     }
 }

 void
 Node::shutdown()
 {
   transport_->close();
   pitTimeoutCheckTimer_->cancel();
   processEventsTimeoutTimer_->cancel();
   pitTimeoutCheckTimerActive_ = false;

   // This will ensure that io_service::work will stop
   ioServiceWork_.reset();
 }

 Node::PendingInterestTable::iterator
 Node::getEntryIndexForExpressedInterest(const Name& name)
 {
   for (PendingInterestTable::iterator i = pendingInterestTable_.begin ();
        i != pendingInterestTable_.end(); ++i)
     {
       if ((*i)->getInterest()->matchesName(name))
         {
           return i;
         }
     }

   return pendingInterestTable_.end();
 }

 Node::RegisteredPrefixTable::iterator
 Node::getEntryForRegisteredPrefix(const Name& name)
 {
   RegisteredPrefixTable::iterator longestPrefix = registeredPrefixTable_.end();

   for (RegisteredPrefixTable::iterator i = registeredPrefixTable_.begin();
        i != registeredPrefixTable_.end();
        ++i)
     {
       if (longestPrefix == registeredPrefixTable_.end() ||
           (*i)->getPrefix()->size() > (*longestPrefix)->getPrefix()->size())
         {
           longestPrefix = i;
         }
     }
   return longestPrefix;
 }

 Node::PendingInterest::PendingInterest(uint64_t pendingInterestId,
                                        const ptr_lib::shared_ptr<const Interest>& interest,
                                        const OnData& onData, const OnTimeout& onTimeout)
 : pendingInterestId_(pendingInterestId),
   interest_(interest),
   onData_(onData), onTimeout_(onTimeout)
 {
   // Set up timeoutTime_.
   if (interest_->getInterestLifetime() >= 0)
     timeoutTimeMilliseconds_ = ndn_getNowMilliseconds() + interest_->getInterestLifetime();
   else
     // No timeout.
     /**
      * @todo Set more meaningful default timeout.  This timeout MUST exist.
      */
     timeoutTimeMilliseconds_ = ndn_getNowMilliseconds() + 4000;
 }

 void
 Node::PendingInterest::callTimeout()
 {
   if (onTimeout_) {
     onTimeout_(interest_);
   }
 }

 }
	/* -- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -- */
	/**
	* Copyright (C) 2013 Regents of the University of California.
	* @author: Jeff Thompson <jefft0@remap.ucla.edu>
	* See COPYING for copyright and distribution information.
	*/

	#include <stdexcept>
	#include "c/util/time.h"

	#include <ndn-cpp/forwarding-entry.hpp>
	#include <ndn-cpp/face-instance.hpp>
	#include <ndn-cpp/node.hpp>

	#include "util/ndnd-id-fetcher.hpp"

	#include <ndn-cpp/security/signature-sha256-with-rsa.hpp>
	#include <ndn-cpp/status-response.hpp>

	using namespace std;
	#if NDN_CPP_HAVE_CXX11
	// In the std library, the placeholders are in a different namespace than boost.
	using namespace ndn::func_lib::placeholders;
	#endif

	namespace ndn {

	uint64_t Node::PendingInterest::lastPendingInterestId_ = 0;
	uint64_t Node::RegisteredPrefix::lastRegisteredPrefixId_ = 0;

	Node::Node(const ptr_lib::shared_ptr<Transport>& transport)
	: pitTimeoutCheckTimerActive_(false)
	, transport_(transport)
	, ndndIdFetcherInterest_(Name("/%C1.M.S.localhost/%C1.M.SRV/ndnd/KEY"), 4000.0)
	{
	ioService_ = ptr_lib::make_shared<boost::asio::io_service>();
	pitTimeoutCheckTimer_ = ptr_lib::make_shared<boost::asio::deadline_timer>(boost::ref(*ioService_));
	processEventsTimeoutTimer_ = ptr_lib::make_shared<boost::asio::deadline_timer>(boost::ref(*ioService_));
	}

	Node::Node(const ptr_lib::shared_ptr<Transport>& transport, const ptr_lib::shared_ptr<boost::asio::io_service> &ioService)
	: ioService_(ioService)
	, pitTimeoutCheckTimerActive_(false)
	, transport_(transport)
	, ndndIdFetcherInterest_(Name("/%C1.M.S.localhost/%C1.M.SRV/ndnd/KEY"), 4000.0)
	{
	pitTimeoutCheckTimer_ = ptr_lib::make_shared<boost::asio::deadline_timer>(boost::ref(*ioService_));
	processEventsTimeoutTimer_ = ptr_lib::make_shared<boost::asio::deadline_timer>(boost::ref(*ioService_));
	}

	uint64_t
	Node::expressInterest(const Interest& interest, const OnData& onData, const OnTimeout& onTimeout)
	{
	if (!transport_->isConnected())
	transport_->connect(*ioService_,
	ptr_lib::bind(&Node::onReceiveElement, this, _1));

	uint64_t pendingInterestId = PendingInterest::getNextPendingInterestId();
	pendingInterestTable_.push_back(ptr_lib::shared_ptr<PendingInterest>(new PendingInterest
	(pendingInterestId, ptr_lib::shared_ptr<const Interest>(new Interest(interest)), onData, onTimeout)));

	transport_->send(interest.wireEncode());

	if (!pitTimeoutCheckTimerActive_) {
	pitTimeoutCheckTimerActive_ = true;
	pitTimeoutCheckTimer_->expires_from_now(boost::posix_time::milliseconds(100));
	pitTimeoutCheckTimer_->async_wait(func_lib::bind(&Node::checkPitExpire, this));
	}

	return pendingInterestId;
	}

	void
	Node::put(const Data &data)
	{
	if (!transport_->isConnected())
	transport_->connect(*ioService_,
	ptr_lib::bind(&Node::onReceiveElement, this, _1));

	transport_->send(data.wireEncode());
	}


	void
	Node::removePendingInterest(uint64_t pendingInterestId)
	{
	// Go backwards through the list so we can erase entries.
	// Remove all entries even though pendingInterestId should be unique.
	for (int i = (int)pendingInterestTable_.size() - 1; i >= 0; --i) {
	if (pendingInterestTable_[i]->getPendingInterestId() == pendingInterestId)
	pendingInterestTable_.erase(pendingInterestTable_.begin() + i);
	}
	}

	uint64_t
	Node::registerPrefix
	(const Name& prefix, const OnInterest& onInterest, const OnRegisterFailed& onRegisterFailed, const ForwardingFlags& flags)
	{
	// Get the registeredPrefixId now so we can return it to the caller.
	uint64_t registeredPrefixId = RegisteredPrefix::getNextRegisteredPrefixId();
	ptr_lib::shared_ptr<const Name> prefixPtr = ptr_lib::make_shared<const Name>(prefix);

	if (ndndId_.size() == 0) {
	// First fetch the ndndId of the connected hub.
	NdndIdFetcher fetcher(ndndId_,
	func_lib::bind(&Node::registerPrefixHelper, this,
	registeredPrefixId, prefixPtr, onInterest, onRegisterFailed, flags),
	func_lib::bind(onRegisterFailed, prefixPtr));

	// @todo: Check if this crash
	// It is OK for func_lib::function make a copy of the function object because the Info is in a ptr_lib::shared_ptr.
	expressInterest(ndndIdFetcherInterest_, fetcher, fetcher);
	}
	else
	registerPrefixHelper(registeredPrefixId, prefixPtr, onInterest, onRegisterFailed, flags);

	return registeredPrefixId;
	}

	void
	Node::removeRegisteredPrefix(uint64_t registeredPrefixId)
	{
	// Go backwards through the list so we can erase entries.
	// Remove all entries even though pendingInterestId should be unique.

	for (RegisteredPrefixTable::iterator i = registeredPrefixTable_.begin();
	i != registeredPrefixTable_.end();
	++i)
	{
	if ((*i)->getRegisteredPrefixId() == registeredPrefixId) {
	ForwardingEntry forwardingEntry("unreg", (i)->getPrefix(), faceId_);
	Data data;
	data.setContent(forwardingEntry.wireEncode());

	SignatureSha256WithRsa signature;
	signature.setValue(Block(Tlv::SignatureValue, ptr_lib::make_shared<Buffer>()));
	data.setSignature(signature);

	// Create an interest where the name has the encoded Data packet.
	Name interestName;
	interestName.append("ndnx");
	interestName.append(ndndId_);
	interestName.append("unreg");
	interestName.append(data.wireEncode());

	Interest interest(interestName);
	interest.setScope(1);
	interest.setInterestLifetime(1000);

	expressInterest(interest, OnData(), OnTimeout());

	registeredPrefixTable_.erase(i);
	break;
	}
	}
	}

	void
	Node::registerPrefixHelper(uint64_t registeredPrefixId,
	const ptr_lib::shared_ptr<const Name>& prefix,
	const OnInterest& onInterest,
	const OnRegisterFailed& onRegisterFailed,
	const ForwardingFlags& flags)
	{
	// Create a ForwardingEntry.

	// AlexA: ndnd ignores any freshness that is larger than 3600 sec and sets 300 sec instead
	// to register "forever" (=2000000000 sec), freshnessPeriod must be omitted
	ForwardingEntry forwardingEntry("selfreg", *prefix, -1, flags, -1);
	Block content = forwardingEntry.wireEncode();

	// Set the ForwardingEntry as the content of a Data packet and sign.
	Data data;
	data.setContent(content);

	// Create an empty signature, since nobody going to verify it for now
	// @todo In the future, we may require real signatures to do the registration
	SignatureSha256WithRsa signature;
	signature.setValue(Block(Tlv::SignatureValue, ptr_lib::make_shared<Buffer>()));
	data.setSignature(signature);

	// Create an interest where the name has the encoded Data packet.
	Name interestName;
	interestName.append("ndnx");
	interestName.append(ndndId_);
	interestName.append("selfreg");
	interestName.append(data.wireEncode());

	Interest interest(interestName);
	interest.setScope(1);
	interest.setInterestLifetime(1000);

	expressInterest(interest,
	func_lib::bind(&Node::registerPrefixFinal, this,
	registeredPrefixId, prefix, onInterest, onRegisterFailed, _1, _2),
	func_lib::bind(onRegisterFailed, prefix));
	}

	void
	Node::registerPrefixFinal(uint64_t registeredPrefixId,
	const ptr_lib::shared_ptr<const Name>& prefix,
	const OnInterest& onInterest,
	const OnRegisterFailed& onRegisterFailed,
	const ptr_lib::shared_ptr<const Interest>&, const ptr_lib::shared_ptr<Data>&data)
	{
	Block content = data->getContent();
	content.parse();

	if (content.getAll().empty())
	{
	onRegisterFailed(prefix);
	return;
	}

	Block::element_iterator val = content.getAll().begin();

	switch(val->type())
	{
	case Tlv::FaceManagement::ForwardingEntry:
	{
	ForwardingEntry entry;
	entry.wireDecode(*val);

	// Save the onInterest callback and send the registration interest.
	registeredPrefixTable_.push_back(ptr_lib::make_shared<RegisteredPrefix>(registeredPrefixId, prefix, onInterest));

	/// @todo Notify user about successful registration

	// succeeded
	return;
	}
	case Tlv::FaceManagement::StatusResponse:
	{
	// failed :(
	StatusResponse resp;
	resp.wireDecode(*val);

	// std::cerr << "StatusReponse: " << resp << std::endl;

	onRegisterFailed(prefix);
	return;
	}
	default:
	{
	// failed :(

	onRegisterFailed(prefix);
	return;
	}
	}
	}

	void
	Node::processEvents(Milliseconds timeout/* = 0 /, bool keepThread/ = false*/)
	{
	try
	{
	if (timeout < 0)
	{
	// do not block if timeout is negative, but process pending events
	ioService_->poll();
	return;
	}

	if (timeout > 0)
	{
	processEventsTimeoutTimer_->expires_from_now(boost::posix_time::milliseconds(timeout));
	processEventsTimeoutTimer_->async_wait(fireProcessEventsTimeout);
	}

	if (keepThread) {
	// work will ensure that ioService_ is running until work object exists
	ioServiceWork_ = ptr_lib::make_shared<boost::asio::io_service::work>(boost::ref(*ioService_));
	}

	ioService_->run();
	}
	catch(Node::ProcessEventsTimeout &)
	{
	// break
	ioService_->reset();
	}
	}

	void
	Node::fireProcessEventsTimeout(const boost::system::error_code& error)
	{
	if (!error) // can fire for some other reason, e.g., cancelled
	throw Node::ProcessEventsTimeout();
	}

	void
	Node::checkPitExpire()
	{
	// Check for PIT entry timeouts. Go backwards through the list so we can erase entries.
	MillisecondsSince1970 nowMilliseconds = ndn_getNowMilliseconds();
	for (int i = (int)pendingInterestTable_.size() - 1; i >= 0; --i) {
	if (pendingInterestTable_[i]->isTimedOut(nowMilliseconds)) {
	// Save the PendingInterest and remove it from the PIT. Then call the callback.
	ptr_lib::shared_ptr<PendingInterest> pendingInterest = pendingInterestTable_[i];
	pendingInterestTable_.erase(pendingInterestTable_.begin() + i);
	pendingInterest->callTimeout();

	// Refresh now since the timeout callback might have delayed.
	nowMilliseconds = ndn_getNowMilliseconds();
	}
	}

	if (!pendingInterestTable_.empty()) {
	pitTimeoutCheckTimerActive_ = true;

	pitTimeoutCheckTimer_->expires_from_now(boost::posix_time::milliseconds(100));
	pitTimeoutCheckTimer_->async_wait(func_lib::bind(&Node::checkPitExpire, this));
	}
	else {
	pitTimeoutCheckTimerActive_ = false;

	if (registeredPrefixTable_.empty()) {
	transport_->close();
	if (!ioServiceWork_) {
	processEventsTimeoutTimer_->cancel();
	}
	}
	}
	}


	void
	Node::onReceiveElement(const Block &block)
	{
	if (block.type() == Tlv::Interest)
	{
	ptr_lib::shared_ptr<Interest> interest(new Interest());
	interest->wireDecode(block);

	RegisteredPrefixTable::iterator entry = getEntryForRegisteredPrefix(interest->getName());
	if (entry != registeredPrefixTable_.end()) {
	(entry)->getOnInterest()((entry)->getPrefix(), interest, transport_, (entry)->getRegisteredPrefixId());
	}
	}
	else if (block.type() == Tlv::Data)
	{
	ptr_lib::shared_ptr<Data> data(new Data());
	data->wireDecode(block);

	PendingInterestTable::iterator entry = getEntryIndexForExpressedInterest(data->getName());
	if (entry != pendingInterestTable_.end()) {
	// Copy pointers to the needed objects and remove the PIT entry before the calling the callback.
	const OnData onData = (*entry)->getOnData();
	const ptr_lib::shared_ptr<const Interest> interest = (*entry)->getInterest();
	pendingInterestTable_.erase(entry);

	if (onData) {
	onData(interest, data);
	}

	if (pendingInterestTable_.empty()) {
	pitTimeoutCheckTimer_->cancel(); // this will cause checkPitExpire invocation
	}
	}
	}
	}

	void
	Node::shutdown()
	{
	transport_->close();
	pitTimeoutCheckTimer_->cancel();
	processEventsTimeoutTimer_->cancel();
	pitTimeoutCheckTimerActive_ = false;

	// This will ensure that io_service::work will stop
	ioServiceWork_.reset();
	}

	Node::PendingInterestTable::iterator
	Node::getEntryIndexForExpressedInterest(const Name& name)
	{
	for (PendingInterestTable::iterator i = pendingInterestTable_.begin ();
	i != pendingInterestTable_.end(); ++i)
	{
	if ((*i)->getInterest()->matchesName(name))
	{
	return i;
	}
	}

	return pendingInterestTable_.end();
	}

	Node::RegisteredPrefixTable::iterator
	Node::getEntryForRegisteredPrefix(const Name& name)
	{
	RegisteredPrefixTable::iterator longestPrefix = registeredPrefixTable_.end();

	for (RegisteredPrefixTable::iterator i = registeredPrefixTable_.begin();
	i != registeredPrefixTable_.end();
	++i)
	{
	if (longestPrefix == registeredPrefixTable_.end() \|\|
	(i)->getPrefix()->size() > (longestPrefix)->getPrefix()->size())
	{
	longestPrefix = i;
	}
	}
	return longestPrefix;
	}

	Node::PendingInterest::PendingInterest(uint64_t pendingInterestId,
	const ptr_lib::shared_ptr<const Interest>& interest,
	const OnData& onData, const OnTimeout& onTimeout)
	: pendingInterestId_(pendingInterestId),
	interest_(interest),
	onData_(onData), onTimeout_(onTimeout)
	{
	// Set up timeoutTime_.
	if (interest_->getInterestLifetime() >= 0)
	timeoutTimeMilliseconds_ = ndn_getNowMilliseconds() + interest_->getInterestLifetime();
	else
	// No timeout.
	/**
	* @todo Set more meaningful default timeout. This timeout MUST exist.
	*/
	timeoutTimeMilliseconds_ = ndn_getNowMilliseconds() + 4000;
	}

	void
	Node::PendingInterest::callTimeout()
	{
	if (onTimeout_) {
	onTimeout_(interest_);
	}
	}

	}