psinterface.hxx

SIP（Session Initiation Protocol）是由IETF定义

#ifndef PSInterface_hxx
#define PSInterface_hxx

/* ====================================================================
 * The Vovida Software License, Version 1.0 
 * 
 * Copyright (c) 2000 Vovida Networks, Inc.  All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 
 * 3. The names "VOCAL", "Vovida Open Communication Application Library",
 *    and "Vovida Open Communication Application Library (VOCAL)" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact [e-mail].
 *
 * 4. Products derived from this software may not be called "VOCAL", nor
 *    may "VOCAL" appear in their name, without prior written
 *    permission of Vovida Networks, Inc.
 * 
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND
 * NON-INFRINGEMENT ARE DISCLAIMED.  IN NO EVENT SHALL VOVIDA
 * NETWORKS, INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT DAMAGES
 * IN EXCESS OF $1,000, NOR FOR ANY INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 * 
 * ====================================================================
 * 
 * This software consists of voluntary contributions made by Vovida
 * Networks, Inc. and many individuals on behalf of Vovida Networks,
 * Inc.  For more information on Vovida Networks, Inc., please see
 * <http://www.vovida.org/>.
 *
 */

static const char* const PSInterface_hxx_Version =
    "$Id: PSInterface.hxx,v 1.11 2002/09/26 01:14:02 bko Exp $";

#include <list>
#include <map>
#include <string>

//User defined
#include "NetworkAddress.h"
#include "Data.hxx"
#include "VMissingDataException.hxx"
#include "VBadDataException.hxx"
#include "HostInterface.hxx"
#include "VNetworkException.hxx"


/**
  Essentially, this class is a wrapper for two HostInterfaces. If one
  fails, the server will fail over and try the other.
*/

class PSInterface
{
    public:

        /**
           Constructor initializes with the name of provision server
           either from a file or from a environment variable.
           Intentionally made private so that it cannot be
           instantiated directly.  It also creates an instance of
           listener in a separate thread to listen for file updates.
        */
        PSInterface(const char* myHostname, const int myPort,
                    const char* altHostname, const int altPort,
		    const char* password = "");

        /// Destructor
        ~PSInterface()
        {}

        /// Return the address of the PServer currently in use

        const NetworkAddress& getNetAddress()
        {
            return _interface->getNetAddress();
        }

        /// Reads an item from provision server
        string readItem(const string &group, const string &name)
        throw (VException&);

        /// Reads a list of items in given group from provision server
        void getList(const string& group, vector < Data > & retList)
        throw (VNetworkException&);

        /// Write an item to provision server
        void writeItem(const string &group, const string &name,
                       const string& contents)
        throw (VNetworkException&);

        /// Delete a subscriber from the server
        void deleteSubscriber(const string& subscriberName)
        throw (VNetworkException &);

        // register and unregister for items and entire groups
        void registerForItem(const string &group, const string &name,
                             const string &hostName) throw (VNetworkException &);

        /// register to receive updates when the items in a group change
        void registerForGroup(const string &group, const string &hostName)
        throw (VNetworkException &);

        /// unregister for an item
        void unregisterForItem(const string &group, const string &name,
                               const string &hostName) throw (VNetworkException &);

        /// unregister for a group
        void unregisterForGroup(const string &group, const string &hostName)
        throw (VNetworkException &);

    private:

        static PSInterface* _instance;

        // keep pointers to the two host interfaces
        HostInterface _primary;
        HostInterface _secondary;

        HostInterface *_interface;

        // swap the active server, which is defined by _interface
        void swapServers(string error);

    static const int NUM_TRIES;
    static const int TIME_DELAY;
    
};

#endif