| /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */ |
| /** |
| * Copyright (c) 2013-2014, Regents of the University of California. |
| * All rights reserved. |
| * |
| * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions). |
| * See AUTHORS.md for complete list of ndn-cxx authors and contributors. |
| * |
| * This file licensed under New BSD License. See COPYING for detailed information about |
| * ndn-cxx library copyright, permissions, and redistribution restrictions. |
| */ |
| |
| #ifndef NDN_TRANSPORT_STREAM_TRANSPORT_HPP |
| #define NDN_TRANSPORT_STREAM_TRANSPORT_HPP |
| |
| #include "../common.hpp" |
| |
| #include <list> |
| |
| namespace ndn { |
| |
| const size_t MAX_LENGTH = 9000; |
| |
| template<class BaseTransport, class Protocol> |
| class StreamTransportImpl |
| { |
| public: |
| typedef BaseTransport base_transport; |
| typedef Protocol protocol; |
| typedef StreamTransportImpl<BaseTransport,Protocol> impl; |
| |
| StreamTransportImpl(base_transport& transport, boost::asio::io_service& ioService) |
| : m_transport(transport) |
| , m_socket(ioService) |
| , m_inputBufferSize(0) |
| , m_connectionInProgress(false) |
| , m_connectTimer(ioService) |
| { |
| } |
| |
| void |
| connectHandler(const boost::system::error_code& error) |
| { |
| m_connectionInProgress = false; |
| m_connectTimer.cancel(); |
| |
| if (!error) |
| { |
| resume(); |
| m_transport.m_isConnected = true; |
| |
| for (std::list<Block>::iterator i = m_sendQueue.begin(); i != m_sendQueue.end(); ++i) |
| m_socket.async_send(boost::asio::buffer(i->wire(), i->size()), |
| bind(&impl::handle_async_send, this, _1, *i)); |
| |
| for (std::list< std::pair<Block,Block> >::iterator i = m_sendPairQueue.begin(); |
| i != m_sendPairQueue.end(); ++i) |
| { |
| std::vector<boost::asio::const_buffer> buffer; |
| buffer.reserve(2); |
| buffer.push_back(boost::asio::buffer(i->first.wire(), i->first.size())); |
| buffer.push_back(boost::asio::buffer(i->second.wire(), i->second.size())); |
| m_socket.async_send(buffer, |
| bind(&impl::handle_async_send2, this, _1, i->first, i->second)); |
| } |
| |
| m_sendQueue.clear(); |
| m_sendPairQueue.clear(); |
| } |
| else |
| { |
| // may need to throw exception |
| m_transport.m_isConnected = false; |
| m_transport.close(); |
| throw Transport::Error(error, "error while connecting to the forwarder"); |
| } |
| } |
| |
| void |
| connectTimeoutHandler(const boost::system::error_code& error) |
| { |
| if (error) // e.g., cancelled timer |
| return; |
| |
| m_connectionInProgress = false; |
| m_transport.m_isConnected = false; |
| m_transport.m_isExpectingData = false; |
| m_socket.cancel(); |
| m_socket.close(); |
| throw Transport::Error(error, "error while connecting to the forwarder"); |
| } |
| |
| void |
| connect(const typename protocol::endpoint& endpoint) |
| { |
| if (!m_connectionInProgress) { |
| m_connectionInProgress = true; |
| |
| // Wait at most 4 time::seconds to connect |
| /// @todo Decide whether this number should be configurable |
| m_connectTimer.expires_from_now(boost::posix_time::seconds(4)); |
| m_connectTimer.async_wait(bind(&impl::connectTimeoutHandler, this, _1)); |
| |
| m_socket.open(); |
| m_socket.async_connect(endpoint, |
| bind(&impl::connectHandler, this, _1)); |
| } |
| } |
| |
| void |
| close() |
| { |
| boost::system::error_code error; // to silently ignore all errors |
| m_connectTimer.cancel(error); |
| m_socket.cancel(error); |
| m_socket.close(error); |
| |
| m_transport.m_isConnected = false; |
| m_transport.m_isExpectingData = false; |
| m_sendQueue.clear(); |
| m_sendPairQueue.clear(); |
| } |
| |
| void |
| pause() |
| { |
| if (m_connectionInProgress) |
| return; |
| |
| if (m_transport.m_isExpectingData) |
| { |
| m_transport.m_isExpectingData = false; |
| m_socket.cancel(); |
| } |
| } |
| |
| void |
| resume() |
| { |
| if (m_connectionInProgress) |
| return; |
| |
| if (!m_transport.m_isExpectingData) |
| { |
| m_transport.m_isExpectingData = true; |
| m_inputBufferSize = 0; |
| m_socket.async_receive(boost::asio::buffer(m_inputBuffer, MAX_LENGTH), 0, |
| bind(&impl::handle_async_receive, this, _1, _2)); |
| } |
| } |
| |
| void |
| send(const Block& wire) |
| { |
| if (!m_transport.m_isConnected) |
| m_sendQueue.push_back(wire); |
| else |
| m_socket.async_send(boost::asio::buffer(wire.wire(), wire.size()), |
| bind(&impl::handle_async_send, this, _1, wire)); |
| } |
| |
| void |
| send(const Block& header, const Block& payload) |
| { |
| if (!m_transport.m_isConnected) |
| { |
| m_sendPairQueue.push_back(std::make_pair(header, payload)); |
| } |
| else |
| { |
| std::vector<boost::asio::const_buffer> buffers; |
| buffers.reserve(2); |
| buffers.push_back(boost::asio::buffer(header.wire(), header.size())); |
| buffers.push_back(boost::asio::buffer(payload.wire(), payload.size())); |
| |
| m_socket.async_send(buffers, |
| bind(&impl::handle_async_send2, this, _1, header, payload)); |
| } |
| } |
| |
| inline bool |
| processAll(uint8_t* buffer, size_t& offset, size_t availableSize) |
| { |
| Block element; |
| while(offset < availableSize) |
| { |
| bool ok = Block::fromBuffer(buffer + offset, availableSize - offset, element); |
| if (!ok) |
| return false; |
| |
| m_transport.receive(element); |
| offset += element.size(); |
| } |
| return true; |
| } |
| |
| void |
| handle_async_receive(const boost::system::error_code& error, std::size_t bytes_recvd) |
| { |
| if (error) |
| { |
| if (error == boost::system::errc::operation_canceled) { |
| // async receive has been explicitly cancelled (e.g., socket close) |
| return; |
| } |
| |
| boost::system::error_code error; // to silently ignore all errors |
| m_socket.cancel(error); |
| m_socket.close(error); // closing at this point may not be that necessary |
| m_transport.m_isConnected = true; |
| m_transport.m_isExpectingData = false; |
| throw Transport::Error(error, "error while receiving data from socket"); |
| } |
| |
| m_inputBufferSize += bytes_recvd; |
| // do magic |
| |
| std::size_t offset = 0; |
| bool ok = processAll(m_inputBuffer, offset, m_inputBufferSize); |
| if (!ok && m_inputBufferSize == MAX_LENGTH && offset == 0) |
| { |
| // very bad... should close connection |
| boost::system::error_code error; // to silently ignore all errors |
| m_socket.cancel(error); |
| m_socket.close(error); |
| m_transport.m_isConnected = false; |
| m_transport.m_isExpectingData = false; |
| throw Transport::Error(boost::system::error_code(), |
| "input buffer full, but a valid TLV cannot be decoded"); |
| } |
| |
| if (offset > 0) |
| { |
| if (offset != m_inputBufferSize) |
| { |
| std::copy(m_inputBuffer + offset, m_inputBuffer + m_inputBufferSize, |
| m_inputBuffer); |
| m_inputBufferSize -= offset; |
| } |
| else |
| { |
| m_inputBufferSize = 0; |
| } |
| } |
| |
| m_socket.async_receive(boost::asio::buffer(m_inputBuffer + m_inputBufferSize, |
| MAX_LENGTH - m_inputBufferSize), 0, |
| bind(&impl::handle_async_receive, this, _1, _2)); |
| } |
| |
| void |
| handle_async_send(const boost::system::error_code& error, const Block& wire) |
| { |
| // pass (needed to keep data block alive during the send) |
| } |
| |
| void |
| handle_async_send2(const boost::system::error_code& error, |
| const Block& header, const Block& payload) |
| { |
| // pass (needed to keep data blocks alive during the send) |
| } |
| |
| protected: |
| base_transport& m_transport; |
| |
| typename protocol::socket m_socket; |
| uint8_t m_inputBuffer[MAX_LENGTH]; |
| size_t m_inputBufferSize; |
| |
| std::list< Block > m_sendQueue; |
| std::list< std::pair<Block, Block> > m_sendPairQueue; |
| bool m_connectionInProgress; |
| |
| boost::asio::deadline_timer m_connectTimer; |
| }; |
| |
| |
| template<class BaseTransport, class Protocol> |
| class StreamTransportWithResolverImpl : public StreamTransportImpl<BaseTransport, Protocol> |
| { |
| public: |
| typedef BaseTransport base_transport; |
| typedef Protocol protocol; |
| typedef StreamTransportWithResolverImpl<BaseTransport,Protocol> impl; |
| |
| StreamTransportWithResolverImpl(base_transport& transport, boost::asio::io_service& ioService) |
| : StreamTransportImpl<base_transport, protocol>(transport, ioService) |
| { |
| } |
| |
| void |
| resolveHandler(const boost::system::error_code& error, |
| typename protocol::resolver::iterator endpoint, |
| const shared_ptr<typename protocol::resolver>&) |
| { |
| if (error) |
| { |
| if (error == boost::system::errc::operation_canceled) |
| return; |
| |
| throw Transport::Error(error, "Error during resolution of host or port"); |
| } |
| |
| typename protocol::resolver::iterator end; |
| if (endpoint == end) |
| { |
| this->m_connectionInProgress = false; |
| this->m_transport.m_isConnected = false; |
| this->m_transport.m_isExpectingData = false; |
| this->m_socket.close(); |
| throw Transport::Error(error, "Unable to resolve because host or port"); |
| } |
| |
| this->m_socket.async_connect(*endpoint, |
| bind(&impl::connectHandler, this, _1)); |
| } |
| |
| void |
| connect(const typename protocol::resolver::query& query) |
| { |
| if (!this->m_connectionInProgress) { |
| this->m_connectionInProgress = true; |
| |
| // Wait at most 4 time::seconds to connect |
| /// @todo Decide whether this number should be configurable |
| this->m_connectTimer.expires_from_now(boost::posix_time::seconds(4)); |
| this->m_connectTimer.async_wait(bind(&impl::connectTimeoutHandler, this, _1)); |
| |
| // typename boost::asio::ip::basic_resolver< protocol > resolver; |
| shared_ptr<typename protocol::resolver> resolver = |
| make_shared<typename protocol::resolver>(ref(this->m_socket.get_io_service())); |
| |
| resolver->async_resolve(query, bind(&impl::resolveHandler, this, _1, _2, resolver)); |
| } |
| } |
| }; |
| |
| |
| } // namespace ndn |
| |
| #endif // NDN_TRANSPORT_STREAM_TRANSPORT_HPP |