UDPSampleOutput.h

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// -*- mode: C++; indent-tabs-mode: nil; c-basic-offset: 4; tab-width: 4; -*-
// vim: set shiftwidth=4 softtabstop=4 expandtab:
/*
 ********************************************************************
 ** NIDAS: NCAR In-situ Data Acquistion Software
 **
 ** 2009, Copyright University Corporation for Atmospheric Research
 **
 ** This program 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 2 of the License, or
 ** (at your option) any later version.
 **
 ** This program 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.
 **
 ** The LICENSE.txt file accompanying this software contains
 ** a copy of the GNU General Public License. If it is not found,
 ** write to the Free Software Foundation, Inc.,
 ** 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 **
 ********************************************************************
*/

#ifndef NIDAS_DYNLD_UDPSAMPLEOUTPUT_H
#define NIDAS_DYNLD_UDPSAMPLEOUTPUT_H

#include <nidas/core/SampleOutput.h>
#include <nidas/core/ConnectionInfo.h>
#include <nidas/util/Thread.h>

#include <poll.h>

namespace nidas {

namespace util {
class Socket;
class ServerSocket;
}

namespace core {
class IOChannel;
class MultipleUDPSockets;
}

namespace dynld {
class UDPSampleOutput: public nidas::core::SampleOutputBase
{
public:

    UDPSampleOutput();

    ~UDPSampleOutput();

    void flush() throw() {}

    void allocateBuffer(size_t len);

    nidas::core::SampleOutput* connected(nidas::core::IOChannel*) throw();

    bool receive(const nidas::core::Sample *s) throw();

    size_t write(const struct iovec* iov,int iovcnt) throw (nidas::util::IOException);

    // void init() throw();

    void close() throw(nidas::util::IOException);

    long long getNumOutputBytes() const { return _nbytesOut; }

    void addNumOutputBytes(int val) { _nbytesOut += val; }

    void fromDOMElement(const xercesc::DOMElement* node)
            throw(nidas::util::InvalidParameterException);

protected:

    UDPSampleOutput* clone(nidas::core::IOChannel* iochannel);

    UDPSampleOutput(UDPSampleOutput&,nidas::core::IOChannel*);

private:
    xercesc::DOMDocument* getProjectDOM() throw(xercesc::DOMException);

    void releaseProjectDOM();

    class VariableListWorker: public nidas::util::Thread
    {
    public:
        VariableListWorker(UDPSampleOutput* output,
            nidas::util::Socket* sock,bool keepOpen);
        ~VariableListWorker();
        int run() throw(nidas::util::Exception);
        void interrupt();
    private:
        UDPSampleOutput* _output;
        nidas::util::Socket* _sock;
        bool _keepOpen;
        VariableListWorker(const VariableListWorker&);
        VariableListWorker& operator=(const VariableListWorker&);
    };

    class ConnectionMonitor: public nidas::util::Thread
    {
    public:
        ConnectionMonitor(nidas::core::MultipleUDPSockets* msock);

        ~ConnectionMonitor();

        int run() throw(nidas::util::Exception);

        void addConnection(nidas::util::Socket*,unsigned short udpport);

        void removeConnection(nidas::util::Socket*,unsigned short udpport);

        void addDestination(const nidas::core::ConnectionInfo&,
            unsigned short udpport);
    private:
        void updatePollfds();
        nidas::core::MultipleUDPSockets* _msock;
        std::list<std::pair<nidas::util::Socket*,unsigned short> > _pendingSockets;
        std::list<std::pair<nidas::util::Socket*,unsigned short> > _pendingRemoveSockets;
        std::vector<std::pair<nidas::util::Socket*,unsigned short> > _sockets;
        std::map<nidas::util::Inet4SocketAddress,nidas::core::ConnectionInfo> _destinations;
        bool _changed;
        nidas::util::Mutex _sockLock;
        struct pollfd* _fds;
        int _nfds;
        ConnectionMonitor(const ConnectionMonitor&);
        ConnectionMonitor& operator=(const ConnectionMonitor&);
    };

    class XMLSocketListener: public nidas::util::Thread
    {
    public:
        XMLSocketListener(UDPSampleOutput* output,
            int xmlPortNumber,ConnectionMonitor* monitor);
        ~XMLSocketListener();
        int run() throw(nidas::util::Exception);
        void interrupt();
    private:
        void checkWorkers() throw();
        void fireWorkers() throw();
        UDPSampleOutput* _output;
        nidas::util::ServerSocket* _sock;
        ConnectionMonitor* _monitor;
        std::list<VariableListWorker*> _workers;
        int _xmlPortNumber;
        XMLSocketListener(const XMLSocketListener&);
        XMLSocketListener& operator=(const XMLSocketListener&);
    };

    nidas::core::MultipleUDPSockets* _mochan;

    xercesc::DOMDocument* _doc;

    bool _projectChanged;

    nidas::util::Mutex _docLock;

    nidas::util::RWLock _docRWLock;

    nidas::util::Mutex _listenerLock;

    unsigned short _xmlPortNumber;

    unsigned short _multicastOutPort;

    XMLSocketListener* _listener;

    ConnectionMonitor* _monitor;

    long long _nbytesOut;

    char *_buffer;

    char* _head;

    char* _tail;

    size_t _buflen;

    char* _eob;

    nidas::core::dsm_time_t _lastWrite;

    int _maxUsecs;

private:

    UDPSampleOutput(const UDPSampleOutput&);

    UDPSampleOutput& operator=(const UDPSampleOutput&);
};

struct InitialUDPDataRequestReply
{
    unsigned int magic;      // should be MAGIC
    unsigned short int xmlTcpPort;
    unsigned short int dataMulticastPort;

    // a concatenated array of null terminated strings
    // 1. multicast address to listen on for data: e.g. "239.0.0.10"
    // 2. hostname which is providing UDP data feed.
    // 3-N: names of DSM where data was sampled.
    char strings[0];

    static const unsigned int MAGIC;
};


struct TCPClientResponse
{
    unsigned int magic;      // should be InitialUDPDataRequestReply::MAGIC
    unsigned short int clientUdpPort;
};

}}

#endif