resource.c

h.248源代码

/********************************************************************
 *
 * File:	resource.c
 *
 * Description:
 *	Resource reservation
 *
 * Copyright 2000-2003, Netergy Microelectronics.  All rights reserved.
 *
 ********************************************************************/

#include "h248app.h"
 
WORD g_wMaxAvailableResources;


WORD GetAvailableResources()
{
  CONNECTION *pConn;
  WORD wReservedResources = 0;

  DLLIST_head(pdllConn);

  while ((pConn = DLLIST_read(pdllConn))) {
    wReservedResources += pConn->ReservedCapRx + pConn->ReservedCapTx;
    DLLIST_next(pdllConn);
  }
  return (g_wMaxAvailableResources - wReservedResources);
}


WORD GetWeight(PROTOCOL_MEDIA_CAP *pCap)
{
  if(pCap->eTxRx == PROTOCOL_TXRX_TX) {

    switch(pCap->oPayload){

    case PROTOCOL_RTPPAYLOAD_PCMA:
    case PROTOCOL_RTPPAYLOAD_PCMU: 
      return G711_ENCODER_WEIGHT;
      break;

    case PROTOCOL_RTPPAYLOAD_G729:
    case PROTOCOL_RTPPAYLOAD_G723: 
    case PROTOCOL_RTPPAYLOAD_G726:  
      return COMPLEX_ENCODER_WEIGHT;
      break;
    }
  }
  else {

    switch(pCap->oPayload){

    case PROTOCOL_RTPPAYLOAD_PCMA:
    case PROTOCOL_RTPPAYLOAD_PCMU: 
      return G711_DECODER_WEIGHT;
      break;

    case PROTOCOL_RTPPAYLOAD_G729:
    case PROTOCOL_RTPPAYLOAD_G723:
    case PROTOCOL_RTPPAYLOAD_G726:   
      return COMPLEX_DECODER_WEIGHT;
      break;
    }
  }
  /* If we do not recognize this payload we return MAX_AVAILABLE_RESOURCES*/
  return g_wMaxAvailableResources;
}

BOOL ReservResource(CONNECTION *pCon,
                    PROTOCOL_MEDIA_CAP *pCap,
                    E_RESERV_TYPE eReservType)
{
  WORD wAvailableResources;
  WORD *pReservedWeight = &(pCon->ReservedCapRx);
  WORD wWeight;

  wAvailableResources = GetAvailableResources();
  wWeight = GetWeight(pCap); 

  if(pCap->eTxRx == PROTOCOL_TXRX_TX)
    pReservedWeight = &(pCon->ReservedCapTx); 

  if( wAvailableResources >= wWeight - *pReservedWeight){
    if(eReservType == RESERV_TYPE_EQUAL ||
       (eReservType == RESERV_TYPE_MIN && *pReservedWeight > wWeight) ||
       (eReservType == RESERV_TYPE_MAX && *pReservedWeight < wWeight)||
       *pReservedWeight == 0)
      *pReservedWeight = wWeight;
    return TRUE;
  }

  return FALSE;
}


BOOL MediaCapSupported(OCTET oPayload)
{
  PROTOCOL_CAP xCap;
  xCap.eMedia = PROTOCOL_MEDIA_AUDIO;
  xCap.xCmn.oPayload = oPayload;
  if(MediaStreamSystemCapEnabled(&xCap))
    return TRUE;
  return FALSE;   
}