daemon/src/net/TCPConnection.cpp

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/*
 * TCPConnection.cpp
 *
 *  Created on: 26.04.2010
 *      Author: morgenro
 */

#include "core/BundleCore.h"
#include "core/GlobalEvent.h"
#include "core/BundleEvent.h"
#include "core/BundleStorage.h"
#include "Configuration.h"

#include "net/TCPConvergenceLayer.h"
#include "net/BundleReceivedEvent.h"
#include "net/ConnectionEvent.h"
#include "net/TransferCompletedEvent.h"
#include "net/TransferAbortedEvent.h"

#include <ibrcommon/TimeMeasurement.h>
#include <ibrcommon/net/NetInterface.h>
#include <ibrcommon/Logger.h>

#include <iostream>
#include <iomanip>

namespace dtn
{
        namespace net
        {
                /*
                 * class TCPConnection
                 */
                TCPConvergenceLayer::TCPConnection::TCPConnection(GenericServer<TCPConnection> &tcpsrv, ibrcommon::tcpstream *stream, const dtn::data::EID &name, const size_t timeout)
                 : GenericConnection<TCPConvergenceLayer::TCPConnection>((GenericServer<TCPConvergenceLayer::TCPConnection>&)tcpsrv), ibrcommon::DetachedThread(),
                   _peer(), _node(Node::NODE_CONNECTED), _tcpstream(stream), _stream(*this, *stream, dtn::daemon::Configuration::getInstance().getNetwork().getTCPChunkSize()), _sender(*this, _keepalive_timeout),
                   _name(name), _timeout(timeout), _lastack(0), _keepalive_timeout(0)
                {
                        _stream.exceptions(std::ios::badbit | std::ios::eofbit);

                        if ( dtn::daemon::Configuration::getInstance().getNetwork().getTCPOptionNoDelay() )
                        {
                                stream->enableNoDelay();
                        }

                        stream->enableLinger(10);
                        stream->enableKeepalive();
                        _node.setProtocol(Node::CONN_TCPIP);
                }

                TCPConvergenceLayer::TCPConnection::~TCPConnection()
                {
                }

                void TCPConvergenceLayer::TCPConnection::queue(const dtn::data::BundleID &bundle)
                {
                        _sender.push(bundle);
                }

                const StreamContactHeader TCPConvergenceLayer::TCPConnection::getHeader() const
                {
                        return _peer;
                }

                const dtn::core::Node& TCPConvergenceLayer::TCPConnection::getNode() const
                {
                        return _node;
                }

                void TCPConvergenceLayer::TCPConnection::rejectTransmission()
                {
                        _stream.reject();
                }

                void TCPConvergenceLayer::TCPConnection::eventShutdown(StreamConnection::ConnectionShutdownCases csc)
                {
                }

                void TCPConvergenceLayer::TCPConnection::eventTimeout()
                {
                        // event
                        ConnectionEvent::raise(ConnectionEvent::CONNECTION_TIMEOUT, _node);

                        // stop the receiver thread
                        this->stop();
                }

                void TCPConvergenceLayer::TCPConnection::eventError()
                {
                }

                void TCPConvergenceLayer::TCPConnection::eventConnectionUp(const StreamContactHeader &header)
                {
                        _peer = header;
                        _node.setURI(header._localeid.getString());
                        _keepalive_timeout = header._keepalive * 1000;

                        // raise up event
                        ConnectionEvent::raise(ConnectionEvent::CONNECTION_UP, _node);
                }

                void TCPConvergenceLayer::TCPConnection::eventConnectionDown()
                {
                        IBRCOMMON_LOGGER_DEBUG(40) << "TCPConnection::eventConnectionDown()" << IBRCOMMON_LOGGER_ENDL;

                        try {
                                // stop the sender
                                _sender.stop();
                        } catch (const ibrcommon::ThreadException &ex) {
                                IBRCOMMON_LOGGER_DEBUG(50) << "TCPConnection::eventConnectionDown(): ThreadException (" << ex.what() << ")" << IBRCOMMON_LOGGER_ENDL;
                        }

                        if (_peer._localeid != dtn::data::EID())
                        {
                                // event
                                ConnectionEvent::raise(ConnectionEvent::CONNECTION_DOWN, _node);
                        }
                }

                void TCPConvergenceLayer::TCPConnection::eventBundleRefused()
                {
                        try {
                                const dtn::data::BundleID bundle = _sentqueue.getnpop();

                                // requeue the bundle
                                TransferAbortedEvent::raise(EID(_node.getURI()), bundle, dtn::net::TransferAbortedEvent::REASON_REFUSED);

                                // set ACK to zero
                                _lastack = 0;

                        } catch (ibrcommon::QueueUnblockedException) {
                                // pop on empty queue!
                                IBRCOMMON_LOGGER(error) << "transfer refused without a bundle in queue" << IBRCOMMON_LOGGER_ENDL;
                        }
                }

                void TCPConvergenceLayer::TCPConnection::eventBundleForwarded()
                {
                        try {
                                const dtn::data::MetaBundle bundle = _sentqueue.getnpop();

                                // signal completion of the transfer
                                TransferCompletedEvent::raise(EID(_node.getURI()), bundle);

                                // raise bundle event
                                dtn::core::BundleEvent::raise(bundle, BUNDLE_FORWARDED);

                                // set ACK to zero
                                _lastack = 0;
                        } catch (ibrcommon::QueueUnblockedException) {
                                // pop on empty queue!
                                IBRCOMMON_LOGGER(error) << "transfer completed without a bundle in queue" << IBRCOMMON_LOGGER_ENDL;
                        }
                }

                void TCPConvergenceLayer::TCPConnection::eventBundleAck(size_t ack)
                {
                        _lastack = ack;
                }

                void TCPConvergenceLayer::TCPConnection::initialize()
                {
                        // start the receiver for incoming bundles + handshake
                        try {
                                start();
                        } catch (const ibrcommon::ThreadException &ex) {
                                IBRCOMMON_LOGGER(error) << "failed to start thread in TCPConnection\n" << ex.what() << IBRCOMMON_LOGGER_ENDL;
                        }
                }

                void TCPConvergenceLayer::TCPConnection::shutdown()
                {
                        // shutdown
                        _stream.shutdown(StreamConnection::CONNECTION_SHUTDOWN_ERROR);

                        try {
                                // abort the connection thread
                                this->stop();
                        } catch (const ibrcommon::ThreadException &ex) {
                                IBRCOMMON_LOGGER_DEBUG(50) << "TCPConnection::shutdown(): ThreadException (" << ex.what() << ")" << IBRCOMMON_LOGGER_ENDL;
                        }
                }

                void TCPConvergenceLayer::TCPConnection::finally()
                {
                        IBRCOMMON_LOGGER_DEBUG(60) << "TCPConnection down" << IBRCOMMON_LOGGER_ENDL;

                        // close the tcpstream
                        try {
                                _tcpstream->close();
                        } catch (const ibrcommon::ConnectionClosedException&) { };

                        try {
                                // shutdown the sender thread
                                _sender.stop();
                        } catch (const std::exception&) { };

                        try {
                                ibrcommon::MutexLock l(_server.mutex());
                                _server.remove(this);
                        } catch (const ibrcommon::MutexException&) { };

                        // clear the queue
                        clearQueue();
                }

                void TCPConvergenceLayer::TCPConnection::run()
                {
                        try {
                                // do the handshake
                                char flags = 0;

                                // enable ACKs and NACKs
                                flags |= dtn::streams::StreamContactHeader::REQUEST_ACKNOWLEDGMENTS;
                                flags |= dtn::streams::StreamContactHeader::REQUEST_NEGATIVE_ACKNOWLEDGMENTS;

                                // do the handshake
                                _stream.handshake(_name, _timeout, flags);

                                // start the sender
                                _sender.start();

                                while (_stream.good())
                                {
                                        try {
                                                // create a new empty bundle
                                                dtn::data::Bundle bundle;

                                                // deserialize the bundle
                                                (*this) >> bundle;

                                                // check the bundle
                                                if ( ( bundle._destination == EID() ) || ( bundle._source == EID() ) )
                                                {
                                                        // invalid bundle!
                                                        throw dtn::data::Validator::RejectedException("destination or source EID is null");
                                                }

                                                // raise default bundle received event
                                                dtn::net::BundleReceivedEvent::raise(_peer._localeid, bundle);
                                        }
                                        catch (const dtn::data::Validator::RejectedException &ex)
                                        {
                                                // bundle rejected
                                                rejectTransmission();

                                                // display the rejection
                                                IBRCOMMON_LOGGER(warning) << "bundle has been rejected: " << ex.what() << IBRCOMMON_LOGGER_ENDL;
                                        }

                                        yield();
                                }
                        } catch (const ibrcommon::ThreadException &ex) {
                                IBRCOMMON_LOGGER(error) << "failed to start thread in TCPConnection\n" << ex.what() << IBRCOMMON_LOGGER_ENDL;
                                _stream.shutdown(StreamConnection::CONNECTION_SHUTDOWN_ERROR);
                        } catch (const std::exception &ex) {
                                IBRCOMMON_LOGGER_DEBUG(10) << "TCPConnection::run(): std::exception (" << ex.what() << ")" << IBRCOMMON_LOGGER_ENDL;
                                _stream.shutdown(StreamConnection::CONNECTION_SHUTDOWN_ERROR);
                        }
                }


                TCPConvergenceLayer::TCPConnection& operator>>(TCPConvergenceLayer::TCPConnection &conn, dtn::data::Bundle &bundle)
                {
                        std::iostream &stream = conn._stream;

                        // activate exceptions for this method
                        if (!stream.good()) throw ibrcommon::IOException("stream went bad");

                        dtn::data::DefaultDeserializer(stream, dtn::core::BundleCore::getInstance()) >> bundle;
                        return conn;
                }

                TCPConvergenceLayer::TCPConnection& operator<<(TCPConvergenceLayer::TCPConnection &conn, const dtn::data::Bundle &bundle)
                {
                        // prepare a measurement
                        ibrcommon::TimeMeasurement m;

                        std::iostream &stream = conn._stream;

                        // create a serializer
                        dtn::data::DefaultSerializer serializer(stream);

                        // put the bundle into the sentqueue
                        conn._sentqueue.push(bundle);

                        // start the measurement
                        m.start();

                        try {
                                // activate exceptions for this method
                                if (!stream.good()) throw ibrcommon::IOException("stream went bad");

                                // transmit the bundle
                                serializer << bundle;

                                // flush the stream
                                stream << std::flush;

                                // stop the time measurement
                                m.stop();

                                // get throughput
                                double kbytes_per_second = (serializer.getLength(bundle) / m.getSeconds()) / 1024;

                                // print out throughput
                                IBRCOMMON_LOGGER_DEBUG(5) << "transfer finished after " << m << " with "
                                                << std::setiosflags(std::ios::fixed) << std::setprecision(2) << kbytes_per_second << " kb/s" << IBRCOMMON_LOGGER_ENDL;

                        } catch (const ibrcommon::Exception &ex) {
                                // the connection not available
                                IBRCOMMON_LOGGER_DEBUG(10) << "connection error: " << ex.what() << IBRCOMMON_LOGGER_ENDL;

                                // forward exception
                                throw;
                        }

                        return conn;
                }

                TCPConvergenceLayer::TCPConnection::Sender::Sender(TCPConnection &connection, size_t &keepalive_timeout)
                 : _abort(false), _connection(connection), _keepalive_timeout(keepalive_timeout)
                {
                }

                TCPConvergenceLayer::TCPConnection::Sender::~Sender()
                {
                        join();
                }

                bool TCPConvergenceLayer::TCPConnection::Sender::__cancellation()
                {
                        // cancel the main thread in here
                        _abort = true;
                        this->abort();

                        // return false, to signal that further cancel (the hardway) is needed
                        return false;
                }

                void TCPConvergenceLayer::TCPConnection::Sender::run()
                {
                        // The queue is not cancel-safe with uclibc, so we need to
                        // disable cancel here
                        int oldstate;
                        ibrcommon::Thread::disableCancel(oldstate);

                        try {
                                dtn::core::BundleStorage &storage = dtn::core::BundleCore::getInstance().getStorage();

                                while (!_abort)
                                {
                                        try {
                                                dtn::data::BundleID _current_transfer = getnpop(true, _keepalive_timeout);

                                                try {
                                                        // read the bundle out of the storage
                                                        const dtn::data::Bundle bundle = storage.get(_current_transfer);

                                                        // enable cancellation during transmission
                                                        ibrcommon::Thread::CancelProtector cprotect(true);

                                                        // send bundle
                                                        _connection << bundle;

                                                } catch (const dtn::core::BundleStorage::NoBundleFoundException&) {
                                                        // send transfer aborted event
                                                        TransferAbortedEvent::raise(EID(_connection._node.getURI()), _current_transfer, dtn::net::TransferAbortedEvent::REASON_BUNDLE_DELETED);
                                                }
                                                
                                                // unset the current transfer
                                                _current_transfer = dtn::data::BundleID();
                                                
                                        } catch (const ibrcommon::QueueUnblockedException &ex) {
                                                switch (ex.reason)
                                                {
                                                        case ibrcommon::QueueUnblockedException::QUEUE_ERROR:
                                                        case ibrcommon::QueueUnblockedException::QUEUE_ABORT:
                                                                throw;
                                                        case ibrcommon::QueueUnblockedException::QUEUE_TIMEOUT:
                                                        {
                                                                // send a keepalive
                                                                _connection.keepalive();
                                                        }
                                                }
                                        }

                                        // idle a little bit
                                        yield();
                                }
                        } catch (const ibrcommon::QueueUnblockedException &ex) {
                                IBRCOMMON_LOGGER_DEBUG(50) << "TCPConnection::Sender::run(): aborted" << IBRCOMMON_LOGGER_ENDL;
                                return;
                        } catch (const std::exception &ex) {
                                IBRCOMMON_LOGGER_DEBUG(10) << "TCPConnection::Sender terminated by exception: " << ex.what() << IBRCOMMON_LOGGER_ENDL;
                        }

                        _connection.stop();
                }

                void TCPConvergenceLayer::TCPConnection::clearQueue()
                {
                        try {
                                while (true)
                                {
                                        const dtn::data::BundleID id = _sender.getnpop();

                                        if (_lastack > 0)
                                        {
                                                // some data are already acknowledged, make a fragment?
                                                //TODO: make a fragment
                                                TransferAbortedEvent::raise(EID(_node.getURI()), id, dtn::net::TransferAbortedEvent::REASON_CONNECTION_DOWN);
                                        }
                                        else
                                        {
                                                // raise transfer abort event for all bundles without an ACK
                                                TransferAbortedEvent::raise(EID(_node.getURI()), id, dtn::net::TransferAbortedEvent::REASON_CONNECTION_DOWN);
                                        }

                                        // set last ack to zero
                                        _lastack = 0;
                                }
                        } catch (ibrcommon::QueueUnblockedException) {
                                // queue emtpy
                        }
                }

                void TCPConvergenceLayer::TCPConnection::keepalive()
                {
                        _stream.keepalive();
                }

                void TCPConvergenceLayer::TCPConnection::Sender::finally()
                {
                        // notify the aborted transfer of the last bundle
                        if (_current_transfer != dtn::data::BundleID())
                        {
                                TransferAbortedEvent::raise(EID(_connection._node.getURI()), _current_transfer, dtn::net::TransferAbortedEvent::REASON_CONNECTION_DOWN);
                        }
                }
        }
}