channels.h

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/*
 * channels.h
 *
 * H.323 protocol handler
 *
 * Open H323 Library
 *
 * Copyright (c) 1998-2001 Equivalence Pty. Ltd.
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Open H323 Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * Portions of this code were written with the assisance of funding from
 * Vovida Networks, Inc. http://www.vovida.com.
 *
 * Contributor(s): ______________________________________.
 *
 * $Revision: 30908 $
 * $Author: rjongbloed $
 * $Date: 2013-11-14 18:03:17 +1100 (Thu, 14 Nov 2013) $
 */

#ifndef OPAL_H323_CHANNELS_H
#define OPAL_H323_CHANNELS_H

#ifdef P_USE_PRAGMA
#pragma interface
#endif

#include <opal_config.h>

#if OPAL_H323

#include <rtp/rtp.h>
#include <h323/transaddr.h>
#include <opal/mediastrm.h>


class H245_OpenLogicalChannel;
class H245_OpenLogicalChannelAck;
class H245_OpenLogicalChannel_forwardLogicalChannelParameters;
class H245_OpenLogicalChannel_reverseLogicalChannelParameters;
class H245_H2250LogicalChannelParameters;
class H245_H2250LogicalChannelAckParameters;
class H245_ArrayOf_GenericInformation;
class H245_MiscellaneousCommand_type;
class H245_MiscellaneousIndication_type;

class H323EndPoint;
class H323Connection;
class H323Capability;



class H323ChannelNumber : public PObject
{
  PCLASSINFO(H323ChannelNumber, PObject);

  public:
    H323ChannelNumber() { number = 0; fromRemote = false; }
    H323ChannelNumber(unsigned number, PBoolean fromRemote);

    virtual PObject * Clone() const;
    virtual PINDEX HashFunction() const;
    virtual void PrintOn(ostream & strm) const;
    virtual Comparison Compare(const PObject & obj) const;

    H323ChannelNumber & operator++(int);
    operator unsigned() const { return number; }
    PBoolean IsFromRemote() const { return fromRemote; }
    
  protected:
    unsigned number;
    PBoolean     fromRemote;
};


class H323Channel : public PObject
{
  PCLASSINFO(H323Channel, PObject);

  public:
    H323Channel(
      H323Connection & connection,        
      const H323Capability & capability   
    );

    ~H323Channel();

    virtual void PrintOn(
      ostream & strm
    ) const;

    enum Directions {
      IsBidirectional,
      IsTransmitter,
      IsReceiver,
      NumDirections
    };
#if PTRACING
    friend ostream & operator<<(ostream & out, Directions dir);
#endif

    virtual Directions GetDirection() const = 0;

    virtual unsigned GetSessionID() const;

    virtual bool SetSessionID(
      unsigned sessionID   
    );

    virtual PBoolean GetMediaTransportAddress(
      OpalTransportAddress & data,        
      OpalTransportAddress & control      
    ) const;

    virtual PBoolean SetInitialBandwidth() = 0;

    virtual bool PreOpen();

    virtual PBoolean Open();

    virtual void Close();

    PBoolean IsOpen() const { return opened && m_terminating == 0; }

    virtual OpalMediaStreamPtr GetMediaStream() const;

    virtual void SetMediaStream(OpalMediaStreamPtr mediaStream);


    virtual PBoolean OnSendingPDU(
      H245_OpenLogicalChannel & openPDU  
    ) const;

    virtual void OnSendOpenAck(
      const H245_OpenLogicalChannel & open,   
      H245_OpenLogicalChannelAck & ack        
    ) const;

    virtual PBoolean OnReceivedPDU(
      const H245_OpenLogicalChannel & pdu,    
      unsigned & errorCode                    
    );

    virtual PBoolean OnReceivedAckPDU(
      const H245_OpenLogicalChannelAck & pdu  
    );

    virtual void OnFlowControl(
      long bitRateRestriction   
    );

    virtual void OnMiscellaneousCommand(
      const H245_MiscellaneousCommand_type & type  
    );

    virtual void OnMiscellaneousIndication(
      const H245_MiscellaneousIndication_type & type  
    );

    virtual void OnJitterIndication(
      DWORD jitter,           
      int skippedFrameCount,  
      int additionalBuffer    
    );

    const H323ChannelNumber & GetNumber() const { return number; }

    void SetNumber(const H323ChannelNumber & num) { number = num; }

    const H323ChannelNumber & GetReverseChannel() const { return reverseChannel; }

    void SetReverseChannel(const H323ChannelNumber & num) { reverseChannel = num; }

    OpalBandwidth GetBandwidthUsed() const { return m_bandwidthUsed; }

    bool SetBandwidthUsed(
      OpalBandwidth bandwidth  
    );

    const H323Capability & GetCapability() const { return *capability; }

    OpalMediaFormat GetMediaFormat() const;

    virtual bool UpdateMediaFormat(const OpalMediaFormat & mediaFormat);

  protected:
    virtual void InternalClose();

    H323EndPoint         & endpoint;
    H323Connection       & connection;
    H323Capability       * capability;
    H323ChannelNumber      number;
    H323ChannelNumber      reverseChannel;
    bool                   opened;
    PAtomicInteger         m_terminating;

  private:
    OpalBandwidth m_bandwidthUsed;
};


PLIST(H323LogicalChannelList, H323Channel);



class H323UnidirectionalChannel : public H323Channel
{
  PCLASSINFO(H323UnidirectionalChannel, H323Channel);

  public:
    H323UnidirectionalChannel(
      H323Connection & connection,        
      const H323Capability & capability,  
      Directions direction                
    );

    ~H323UnidirectionalChannel();

    virtual Directions GetDirection() const;

    virtual PBoolean SetInitialBandwidth();

    virtual bool PreOpen();

    virtual PBoolean Open();

    virtual bool UpdateMediaFormat(const OpalMediaFormat & mediaFormat);

    virtual OpalMediaStreamPtr GetMediaStream() const;

    virtual void SetMediaStream(OpalMediaStreamPtr mediaStream);


  protected:
    virtual void InternalClose();

    bool               receiver;
    OpalMediaStreamPtr m_mediaStream;
};


class H323BidirectionalChannel : public H323Channel
{
  PCLASSINFO(H323BidirectionalChannel, H323Channel);

  public:
    H323BidirectionalChannel(
      H323Connection & connection,        
      const H323Capability & capability   
    );

    virtual Directions GetDirection() const;
};



class H323_RealTimeChannel : public H323UnidirectionalChannel
{
  PCLASSINFO(H323_RealTimeChannel, H323UnidirectionalChannel);

  public:
    H323_RealTimeChannel(
      H323Connection & connection,        
      const H323Capability & capability,  
      Directions direction                
    );

    virtual PBoolean OnSendingPDU(
      H245_OpenLogicalChannel & openPDU  
    ) const;

    virtual void OnSendOpenAck(
      const H245_OpenLogicalChannel & open,   
      H245_OpenLogicalChannelAck & ack        
    ) const;

    virtual void OnSendOpenAck(
      H245_H2250LogicalChannelAckParameters & param 
    ) const;


    virtual PBoolean OnReceivedPDU(
      const H245_OpenLogicalChannel & pdu,    
      unsigned & errorCode                    
    );

    virtual PBoolean OnReceivedAckPDU(
      const H245_OpenLogicalChannelAck & pdu 
    );

    virtual PBoolean OnSendingPDU(
      H245_H2250LogicalChannelParameters & param  
    ) const;

    virtual PBoolean OnSendingAltPDU(
      H245_ArrayOf_GenericInformation & alternate  
    ) const = 0;

    virtual PBoolean OnReceivedPDU(
      const H245_H2250LogicalChannelParameters & param, 
      unsigned & errorCode                              
    );

    virtual PBoolean OnReceivedAckPDU(
      const H245_H2250LogicalChannelAckParameters & param 
    );

    RTP_DataFrame::PayloadTypes GetDynamicRTPPayloadType() const;
};



class H323DataChannel : public H323UnidirectionalChannel
{
  PCLASSINFO(H323DataChannel, H323UnidirectionalChannel);

  public:
    H323DataChannel(
      H323Connection & connection,        
      const H323Capability & capability,  
      Directions direction,               
      unsigned sessionID                  
    );

    ~H323DataChannel();

    virtual unsigned GetSessionID() const;

    virtual PBoolean OnSendingPDU(
      H245_OpenLogicalChannel & openPDU  
    ) const;

    virtual void OnSendOpenAck(
      const H245_OpenLogicalChannel & open,   
      H245_OpenLogicalChannelAck & ack        
    ) const;

    virtual PBoolean OnReceivedPDU(
      const H245_OpenLogicalChannel & pdu,    
      unsigned & errorCode                    
    );

    virtual PBoolean OnReceivedAckPDU(
      const H245_OpenLogicalChannelAck & pdu 
    );

    virtual PBoolean CreateListener();

    virtual PBoolean CreateTransport();

  protected:
    virtual void InternalClose();

    unsigned        sessionID;
    H323Listener  * listener;
    PBoolean            autoDeleteListener;
    H323Transport * transport;
    PBoolean            autoDeleteTransport;
    PBoolean            separateReverseChannel;
};


#endif // OPAL_H323

#endif // OPAL_H323_CHANNELS_H