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): ______________________________________.
 *
 * $Log: channels.h,v $
 * Revision 2.16  2007/03/29 05:15:48  csoutheren
 * Pass OpalConnection to OpalMediaSream constructor
 * Add ID to OpalMediaStreams so that transcoders can match incoming and outgoing codecs
 *
 * Revision 2.15  2006/08/10 05:10:30  csoutheren
 * Various H.323 stability patches merged in from DeimosPrePLuginBranch
 *
 * Revision 2.14.6.1  2006/08/09 12:49:21  csoutheren
 * Improve stablity under heavy H.323 load
 *
 * Revision 2.14  2005/11/30 13:35:26  csoutheren
 * Changed tags for Doxygen
 *
 * Revision 2.13  2005/09/04 06:23:38  rjongbloed
 * Added OpalMediaCommand mechanism (via PNotifier) for media streams
 *   and media transcoders to send commands back to remote.
 *
 * Revision 2.12  2005/08/31 13:19:25  rjongbloed
 * Added mechanism for controlling media (especially codecs) including
 *   changing the OpalMediaFormat option list (eg bit rate) and a completely
 *   new OpalMediaCommand abstraction for things like video fast update.
 *
 * Revision 2.11  2002/11/10 11:33:16  robertj
 * Updated to OpenH323 v1.10.3
 *
 * Revision 2.10  2002/09/16 02:52:33  robertj
 * Added #define so can select if #pragma interface/implementation is used on
 *   platform basis (eg MacOS) rather than compiler, thanks Robert Monaghan.
 *
 * Revision 2.9  2002/09/04 06:01:46  robertj
 * Updated to OpenH323 v1.9.6
 *
 * Revision 2.8  2002/07/01 04:56:29  robertj
 * Updated to OpenH323 v1.9.1
 *
 * Revision 2.7  2002/04/18 03:41:28  robertj
 * Fixed logical channel so does not delete media stream too early.
 *
 * Revision 2.6  2002/02/11 09:32:11  robertj
 * Updated to openH323 v1.8.0
 *
 * Revision 2.5  2002/02/11 07:37:21  robertj
 * Added media bypass for streams between compatible protocols.
 *
 * Revision 2.4  2002/01/22 04:56:55  robertj
 * Update from OpenH323, rev 1.26 to 1.28
 *
 * Revision 2.3  2002/01/14 06:35:56  robertj
 * Updated to OpenH323 v1.7.9
 *
 * Revision 2.2  2001/11/02 10:45:19  robertj
 * Updated to OpenH323 v1.7.3
 *
 * Revision 2.1  2001/10/15 04:30:09  robertj
 * Added delayed start of media patch threads.
 *
 * Revision 2.0  2001/07/27 15:48:24  robertj
 * Conversion of OpenH323 to Open Phone Abstraction Library (OPAL)
 *
 * Revision 1.40  2002/09/16 01:14:15  robertj
 * Added #define so can select if #pragma interface/implementation is used on
 *   platform basis (eg MacOS) rather than compiler, thanks Robert Monaghan.
 *
 * Revision 1.39  2002/09/03 06:19:36  robertj
 * Normalised the multi-include header prevention ifdef/define symbol.
 *
 * Revision 1.38  2002/08/05 10:03:47  robertj
 * Cosmetic changes to normalise the usage of pragma interface/implementation.
 *
 * Revision 1.37  2002/06/25 08:30:08  robertj
 * Changes to differentiate between stright G.723.1 and G.723.1 Annex A using
 *   the OLC dataType silenceSuppression field so does not send SID frames
 *   to receiver codecs that do not understand them.
 *
 * Revision 1.36  2002/05/23 04:53:54  robertj
 * Added function to remove a filter from logical channel.
 *
 * Revision 1.35  2002/05/10 05:46:46  robertj
 * Added session ID to the data logical channel class.
 *
 * Revision 1.34  2002/05/02 07:56:24  robertj
 * Added automatic clearing of call if no media (RTP data) is transferred in a
 *   configurable (default 5 minutes) amount of time.
 *
 * Revision 1.33  2002/05/02 06:28:50  robertj
 * Fixed problem with external RTP channels not fast starting.
 *
 * Revision 1.32  2002/04/17 05:56:28  robertj
 * Added trace output of H323Channel::Direction enum.
 *
 * Revision 1.31  2002/02/09 04:39:01  robertj
 * Changes to allow T.38 logical channels to use single transport which is
 *   now owned by the OpalT38Protocol object instead of H323Channel.
 *
 * Revision 1.30  2002/02/05 08:13:20  robertj
 * Added ability to not have addresses when external RTP channel created.
 *
 * Revision 1.29  2002/01/22 22:48:21  robertj
 * Fixed RFC2833 support (transmitter) requiring large rewrite
 *
 * Revision 1.28  2002/01/17 07:04:57  robertj
 * Added support for RFC2833 embedded DTMF in the RTP stream.
 *
 * Revision 1.27  2002/01/17 00:10:37  robertj
 * Fixed double copy of rtpPayloadType in RTP channel, caused much confusion.
 *
 * Revision 1.26  2002/01/14 05:18:16  robertj
 * Fixed typo on external RTP channel constructor.
 *
 * Revision 1.25  2002/01/10 05:13:50  robertj
 * Added support for external RTP stacks, thanks NuMind Software Systems.
 *
 * Revision 1.24  2001/10/23 02:18:06  dereks
 * Initial release of CU30 video codec.
 *
 * Revision 1.23  2001/07/24 02:26:53  robertj
 * Added start for handling reverse channels.
 *
 * Revision 1.22  2001/07/17 04:44:29  robertj
 * Partial implementation of T.120 and T.38 logical channels.
 *
 * Revision 1.21  2001/02/09 05:16:24  robertj
 * Added #pragma interface for GNU C++.
 *
 * Revision 1.20  2001/01/25 07:27:14  robertj
 * Major changes to add more flexible OpalMediaFormat class to normalise
 *   all information about media types, especially codecs.
 *
 * Revision 1.19  2000/10/19 04:05:20  robertj
 * Added compare function for logical channel numbers, thanks Yuriy Ershov.
 *
 * Revision 1.18  2000/09/22 01:35:02  robertj
 * Added support for handling LID's that only do symmetric codecs.
 *
 * Revision 1.17  2000/08/31 08:15:32  robertj
 * Added support for dynamic RTP payload types in H.245 OpenLogicalChannel negotiations.
 *
 * Revision 1.16  2000/08/21 02:50:19  robertj
 * Fixed race condition if close call just as slow start media channels are opening.
 *
 * Revision 1.15  2000/06/15 01:46:13  robertj
 * Added channel pause (aka mute) functions.
 *
 * Revision 1.14  2000/05/18 11:53:33  robertj
 * Changes to support doc++ documentation generation.
 *
 * Revision 1.13  2000/05/02 04:32:23  robertj
 * Fixed copyright notice comment.
 *
 * Revision 1.12  1999/12/23 23:02:34  robertj
 * File reorganision for separating RTP from H.323 and creation of LID for VPB support.
 *
 * Revision 1.11  1999/11/19 09:06:30  robertj
 * Changed to close down logical channel if get a transmit codec error.
 *
 * Revision 1.10  1999/11/06 05:37:44  robertj
 * Complete rewrite of termination of connection to avoid numerous race conditions.
 *
 * Revision 1.9  1999/09/08 04:05:48  robertj
 * Added support for video capabilities & codec, still needs the actual codec itself!
 *
 * Revision 1.8  1999/08/31 12:34:18  robertj
 * Added gatekeeper support.
 *
 * Revision 1.7  1999/07/09 06:09:49  robertj
 * Major implementation. An ENORMOUS amount of stuff added everywhere.
 *
 * Revision 1.6  1999/06/14 05:15:55  robertj
 * Changes for using RTP sessions correctly in H323 Logical Channel context
 *
 * Revision 1.5  1999/06/13 12:41:14  robertj
 * Implement logical channel transmitter.
 * Fixed H245 connect on receiving call.
 *
 * Revision 1.4  1999/06/09 05:26:19  robertj
 * Major restructuring of classes.
 *
 * Revision 1.3  1999/06/06 06:06:36  robertj
 * Changes for new ASN compiler and v2 protocol ASN files.
 *
 * Revision 1.2  1999/04/26 06:14:46  craigs
 * Initial implementation for RTP decoding and lots of stuff
 * As a whole, these changes are called "First Noise"
 *
 * Revision 1.1  1999/01/16 01:31:07  robertj
 * Initial revision
 *
 */

#ifndef __OPAL_CHANNELS_H
#define __OPAL_CHANNELS_H

#ifdef P_USE_PRAGMA
#pragma interface
#endif


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


class OpalMediaStream;
class OpalMediaCommand;

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

class H323EndPoint;
class H323Connection;
class H323Capability;
class H323_RTP_Session;



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

  public:
    H323ChannelNumber() { number = 0; fromRemote = FALSE; }
    H323ChannelNumber(unsigned number, BOOL 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; }
    BOOL IsFromRemote() const { return fromRemote; }
    
  protected:
    unsigned number;
    BOOL     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 GetMediaTransportAddress(
      OpalTransportAddress & data,        
      OpalTransportAddress & control      
    ) const;

    virtual BOOL SetInitialBandwidth() = 0;

    virtual BOOL Open();

    virtual BOOL Start() = 0;

    virtual void Close();

    BOOL IsOpen() const { return opened && !terminating; }

    virtual OpalMediaStream * GetMediaStream(
      BOOL deleted = FALSE
    ) const = 0;


    virtual BOOL OnSendingPDU(
      H245_OpenLogicalChannel & openPDU  
    ) const = 0;

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

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

    virtual BOOL 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; }

    unsigned GetBandwidthUsed() const { return bandwidthUsed; }

    BOOL SetBandwidthUsed(
      unsigned bandwidth  
    );

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

    BOOL IsPaused() const { return paused; }

    void SetPause(
      BOOL pause   
    ) { paused = pause; }

  protected:
    H323EndPoint         & endpoint;
    H323Connection       & connection;
    H323Capability       * capability;
    H323ChannelNumber      number;
    H323ChannelNumber      reverseChannel;
    BOOL                   opened;
    BOOL                   paused;
    BOOL                   terminating;

  private:
    unsigned 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 BOOL SetInitialBandwidth();

    virtual BOOL Open();

    virtual BOOL Start();

    virtual void Close();

    virtual void OnMiscellaneousCommand(
      const H245_MiscellaneousCommand_type & type  
    );

    virtual OpalMediaStream * GetMediaStream(BOOL deleted = FALSE) const;

  protected:
    PDECLARE_NOTIFIER(OpalMediaCommand, H323UnidirectionalChannel, OnMediaCommand);

    BOOL              receiver;
    mutable OpalMediaStream * mediaStream;
};


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

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

    virtual Directions GetDirection() const;

    virtual BOOL Start();
};



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

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

    virtual BOOL OnSendingPDU(
      H245_OpenLogicalChannel & openPDU  
    ) const;

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

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

    virtual BOOL OnReceivedAckPDU(
      const H245_OpenLogicalChannelAck & pdu 
    );

    virtual BOOL OnSendingPDU(
      H245_H2250LogicalChannelParameters & param  
    ) const = 0;

    virtual void OnSendOpenAck(
      H245_H2250LogicalChannelAckParameters & param 
    ) const = 0;

    virtual BOOL OnReceivedPDU(
      const H245_H2250LogicalChannelParameters & param, 
      unsigned & errorCode                              
    ) = 0;

    virtual BOOL OnReceivedAckPDU(
      const H245_H2250LogicalChannelAckParameters & param 
    ) = 0;

    virtual BOOL SetDynamicRTPPayloadType(
      int newType  
    );

    RTP_DataFrame::PayloadTypes GetDynamicRTPPayloadType() const { return rtpPayloadType; }

  protected:
    RTP_DataFrame::PayloadTypes rtpPayloadType;
};



class H323_RTPChannel : public H323_RealTimeChannel
{
  PCLASSINFO(H323_RTPChannel, H323_RealTimeChannel);

  public:
    H323_RTPChannel(
      H323Connection & connection,        
      const H323Capability & capability,  
      Directions direction,               
      RTP_Session & rtp                   
    );

    ~H323_RTPChannel();

    virtual unsigned GetSessionID() const;

    virtual BOOL OnSendingPDU(
      H245_H2250LogicalChannelParameters & param  
    ) const;

    virtual void OnSendOpenAck(
      H245_H2250LogicalChannelAckParameters & param 
    ) const;

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

    virtual BOOL OnReceivedAckPDU(
      const H245_H2250LogicalChannelAckParameters & param 
    );

  protected:
    RTP_Session      & rtpSession;
    H323_RTP_Session & rtpCallbacks;
};



class H323_ExternalRTPChannel : public H323_RealTimeChannel
{
  PCLASSINFO(H323_ExternalRTPChannel, H323_RealTimeChannel);

  public:
    H323_ExternalRTPChannel(
      H323Connection & connection,        
      const H323Capability & capability,  
      Directions direction,               
      unsigned sessionID                  
    );
    H323_ExternalRTPChannel(
      H323Connection & connection,        
      const H323Capability & capability,  
      Directions direction,               
      unsigned sessionID,                 
      const H323TransportAddress & data,  
      const H323TransportAddress & control
    );
    H323_ExternalRTPChannel(
      H323Connection & connection,        
      const H323Capability & capability,  
      Directions direction,               
      unsigned sessionID,                 
      const PIPSocket::Address & ip,      
      WORD dataPort                       
    );

    virtual unsigned GetSessionID() const;

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

    virtual BOOL Start();

    virtual void Receive();

    virtual void Transmit();

    virtual BOOL OnSendingPDU(
      H245_H2250LogicalChannelParameters & param  
    ) const;

    virtual void OnSendOpenAck(
      H245_H2250LogicalChannelAckParameters & param 
    ) const;

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

    virtual BOOL OnReceivedAckPDU(
      const H245_H2250LogicalChannelAckParameters & param 
    );

    void SetExternalAddress(
      const H323TransportAddress & data,  
      const H323TransportAddress & control
    );

    const H323TransportAddress & GetRemoteMediaAddress()        const { return remoteMediaAddress; }
    const H323TransportAddress & GetRemoteMediaControlAddress() const { return remoteMediaControlAddress; }

    BOOL GetRemoteAddress(
      PIPSocket::Address & ip,
      WORD & dataPort
    ) const;

  protected:
    void Construct(H323Connection & conn, unsigned id);

    unsigned             sessionID;
    H323TransportAddress externalMediaAddress;
    H323TransportAddress externalMediaControlAddress;
    H323TransportAddress remoteMediaAddress;
    H323TransportAddress remoteMediaControlAddress;
};



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

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

    ~H323DataChannel();

    virtual void Close();

    virtual unsigned GetSessionID() const;

    virtual BOOL OnSendingPDU(
      H245_OpenLogicalChannel & openPDU  
    ) const;

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

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

    virtual BOOL OnReceivedAckPDU(
      const H245_OpenLogicalChannelAck & pdu 
    );

    virtual BOOL CreateListener();

    virtual BOOL CreateTransport();

  protected:
    unsigned        sessionID;
    H323Listener  * listener;
    BOOL            autoDeleteListener;
    H323Transport * transport;
    BOOL            autoDeleteTransport;
    BOOL            separateReverseChannel;
};


#endif // __OPAL_CHANNELS_H

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