rtcp_packet.cpp

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// RTCP_Packet.cpp,v 5.5 2003/07/24 22:43:41 parsons Exp
#include "RTCP_Packet.h"
#include "RTP.h"

RTCP_Packet::RTCP_Packet(void)
{
  this->chd_.ver_ = 2;
  this->chd_.count_ = 0;
  this->chd_.pad_ = 0;
  this->chd_.length_ = 0;
  this->packet_data_ = 0;
}

RTCP_Packet::RTCP_Packet(char* buffer)
{
  // Parse the common part of the control packet header.
  this->chd_.ver_ = (buffer[0] & 0xC0) >> 6;

  if (this->chd_.ver_ != RTP_VERSION)
    ACE_DEBUG ((LM_DEBUG,
                "RTCP_Packet::RTCP_Packet version incorrect"));

  this->chd_.pad_ = (buffer[0] & 0x20) >> 5;
  this->chd_.count_ = buffer[0] & 0x1F;
  this->chd_.pt_ = buffer[1];
  this->chd_.length_ = ntohs(*(ACE_UINT16*)&buffer[2]);
  this->packet_data_ = 0;
}

RTCP_Packet::~RTCP_Packet(void)
{
}

void
RTCP_Packet::get_packet_data(char **buffer, ACE_UINT16 &length)
{
  length = this->packet_size();

  // buiidPacket is defined for each child of RTCP_Packet
  // buildPacket creates a snapshot of the RTCP packet in the buffer pktData
  this->build_packet ();

  *buffer = this->packet_data_;
}

int
RTCP_Packet::is_valid (char is_first)
{
  // make sure the RTP version is correct
  if (this->chd_.ver_ != RTP_VERSION)
    return 0;

  // these checks are only for the first RTCP packet in a compound packet
  if (is_first)
    {
      // the payload type must be RR or SR
      if ((this->chd_.pt_ != RTCP_PT_SR) && (this->chd_.pt_ != RTCP_PT_RR))
        return 0;

      // the padding bit must not be set
      if (this->chd_.pad_ != 0)
        return 0;
    }

  return 1;

}

/*
 * RTCP_BYE_Packet
 */

RTCP_BYE_Packet::RTCP_BYE_Packet(ACE_UINT32 *ssrc_list,
                                 unsigned char length,
                                 const char *text)
{
  this->chd_.ver_ = 2;
  this->chd_.count_ = length;
  this->chd_.pt_ = RTCP_PT_BYE;

  if (length)
    {
      ACE_NEW (this->ssrc_list_,
               ACE_UINT32[length]);

      this->ssrc_list_length_ = length;

      for (int i=0; i<length; i++)
        this->ssrc_list_[i] = ssrc_list[i];
    }

  // Optional - if there is a reason for leaving, store it.
  // The reason is padded with extra zeros because the packet must
  // end on an even 32-bit boundary.
  memset(this->reason_, 0, sizeof(this->reason_));
  if (text)
    {
      size_t text_length = ACE_OS::strlen(text);
      memcpy(this->reason_, text, text_length);
      this->reason_length_ = ACE_static_cast (unsigned char, text_length);
    }
  else
    this->reason_length_ = 0;

  // Set the packet length
  this->chd_.length_ = this->chd_.count_ + (this->reason_length_+1)/4;
  if ((this->reason_length_+1)%4)
    this->chd_.length_++;

  this->packet_data_ = 0;
}

//==============================================================================

RTCP_BYE_Packet::RTCP_BYE_Packet(char* buffer, int *len)
                 : RTCP_Packet(buffer)
{
  unsigned int index = 0;
  unsigned int j;

  // The common part of the header is initialized in the parent.
  index=4;

  ACE_NEW (this->ssrc_list_,
           ACE_UINT32[this->chd_.count_]);
  this->ssrc_list_length_ = this->chd_.count_;

  // Store the source ids of the sources leaving the session
  for (j=0; j<this->chd_.count_; j++)
    {
      this->ssrc_list_[j] = ntohl(*(ACE_UINT32*)&buffer[index]);
      index+=4;
    }

  // Optional - store the reason for leaving
  unsigned int temp = this->chd_.length_; // Borland reports a warning on the
                                          // following line with out this.
  memset(this->reason_, 0, sizeof(this->reason_));
  if (temp > this->chd_.count_)
    {
      this->reason_length_ = buffer[index];
      index++;
      memcpy(this->reason_, &buffer[index], this->reason_length_);
      index+=this->reason_length_;

    }
  else
    this->reason_length_ = 0;

  // Decrement the length by the size of this message. This is necessary
  // because multiple RTCP packets may be contained in a single UDP packet.
  *len-=(chd_.length_+1)*4;

  this->packet_data_ = 0;
}

//==============================================================================

RTCP_BYE_Packet::~RTCP_BYE_Packet(void)
{
  if (this->ssrc_list_)
    delete []this->ssrc_list_;
  if (this->packet_data_)
    delete []this->packet_data_;
}

//==============================================================================

unsigned int
RTCP_BYE_Packet::packet_size(void)
{
  ACE_UINT16 size = (1+chd_.count_) * 4;

  if (this->reason_length_ > 0)
    {
      size += this->reason_length_ + 1;
      if (size%4)
        size += 4 - size%4; // pad with zeros to even 32 bit bound
    }

  return size;
}

//==============================================================================

void
RTCP_BYE_Packet::ssrc_list(ACE_UINT32 **ssrc_list, unsigned char &length)
{
  *ssrc_list = this->ssrc_list_;
  length = this->ssrc_list_length_;
}

//==============================================================================

const char *
RTCP_BYE_Packet::reason (void)
{
  ACE_CString reason = (const char *)this->reason_;

  return reason.c_str();
}

//==============================================================================

void
RTCP_BYE_Packet::build_packet(void)
{
  unsigned int index;
  unsigned int i;

  if (this->packet_data_)
    delete []this->packet_data_;

  ACE_NEW (this->packet_data_,
           char[this->packet_size()]);

  index = 0;
  this->packet_data_[index] = (this->chd_.ver_ << 6) |
                              (this->chd_.pad_ << 5) |
                               this->chd_.count_;
  index++;
  this->packet_data_[index] = this->chd_.pt_;
  index++;
  *((ACE_UINT16*)&this->packet_data_[index]) = htons(this->chd_.length_);
  index+=2;

  for (i=0; i<this->chd_.count_; i++)
    {
      *((ACE_UINT32*)&this->packet_data_[index]) = htonl(this->ssrc_list_[i]);
      index+=4;
    }

  if (this->reason_)
    {
      this->packet_data_[index] = this->reason_length_;
      index++;
      memcpy(&this->packet_data_[index], this->reason_, this->reason_length_);
      index += this->reason_length_;
      while (index < this->packet_size())
        {
          this->packet_data_[index] = 0;
          index ++;
        }
    }
}

void
RTCP_BYE_Packet::dump (void)
{
  ACE_DEBUG ((LM_DEBUG,
              "\nRTCP_BYE_Packet:: from ssrc(s) "));
  for (int i=0; i< this->ssrc_list_length_; i++)
    ACE_DEBUG ((LM_DEBUG,
                "%u ",
                this->ssrc_list_[i]));
  ACE_DEBUG ((LM_DEBUG,
              "\n    Reason '%s'\n",
              this->reason_));
}

RTCP_RR_Packet::RTCP_RR_Packet(ACE_UINT32 ssrc, RR_Block *blocks)
{
  RR_Block *block_ptr = blocks;

  this->chd_.count_ = 0;
  this->chd_.ver_ = 2;
  this->chd_.pt_ = RTCP_PT_RR;
  this->ssrc_ = ssrc;
  this->rr_ = blocks;

  while (block_ptr)
    {
      this->chd_.count_++;

      // Can only have 31 receiver reports
      if (this->chd_.count_ == 31)
        {
          block_ptr->next_ = 0;
          break;
        }

      block_ptr = block_ptr->next_;
    }

  this->chd_.length_ = 1+6*this->chd_.count_; // + profile specific extensions ??

  this->packet_data_ = 0;
}

//==============================================================================

RTCP_RR_Packet::RTCP_RR_Packet (char* buffer,
                                int *len)
  :RTCP_Packet (buffer)
{
  unsigned int i = 0;
  RR_Block *local_block_ptr = 0;

  this->rr_ = 0;

  // The common part of the header is initialized in the parent.
  i=4;
  this->ssrc_ = ntohl(*(ACE_UINT32*)&buffer[i]);
  i+=4;
  for (unsigned int j=0; j<this->chd_.count_; j++)
    {
      if (j==0)
        {
          ACE_NEW (this->rr_,
                   RR_Block);
          local_block_ptr = this->rr_;
        }
      else
        {
          ACE_NEW (local_block_ptr->next_,
                   RR_Block);
          local_block_ptr = local_block_ptr->next_;
        }

      local_block_ptr->next_ = 0;
      local_block_ptr->ssrc_ = ntohl(*(ACE_UINT32*)&buffer[i]);
      i+=4;
      ACE_UINT32 temp = ntohl(*(ACE_UINT32*)&buffer[i]);
      local_block_ptr->fraction_ = (temp&0xff000000) >> 24;
      local_block_ptr->lost_ = temp & 0x00ffffff;
      i+=4;
      local_block_ptr->last_seq_ = ntohl(*(ACE_UINT32*)&buffer[i]);
      i+=4;
      local_block_ptr->jitter_ = ntohl(*(ACE_UINT32*)&buffer[i]);
      i+=4;
      local_block_ptr->lsr_ = ntohl(*(ACE_UINT32*)&buffer[i]);
      i+=4;
      local_block_ptr->dlsr_ = ntohl(*(ACE_UINT32*)&buffer[i]);
      i+=4;
    }

  *len-=(this->chd_.length_+1)*4;

  this->packet_data_ = 0;
}

//==============================================================================

RTCP_RR_Packet::~RTCP_RR_Packet(void)
{
  RR_Block *prev;

  if (this->rr_)
    {
      while (this->rr_)
        {
          prev = this->rr_;
          this->rr_ = this->rr_->next_;
          delete prev;
        }
    }

  if (this->packet_data_)
    delete []this->packet_data_;
}

//==============================================================================

unsigned int
RTCP_RR_Packet::packet_size(void)
{
    ACE_UINT16 size = (2+this->chd_.count_*6) * 4;
    return size;
}

//==============================================================================

void
RTCP_RR_Packet::build_packet(void)
{
  int index;
  RR_Block *local_block_ptr;

  if (this->packet_data_)
    delete []this->packet_data_;

  ACE_NEW (this->packet_data_,
           char [this->packet_size ()]);

  index = 0;
  this->packet_data_[index] = (this->chd_.ver_ << 6) |
                              (this->chd_.pad_ << 5) |
                              this->chd_.count_;
  index++;
  this->packet_data_[index] = chd_.pt_;
  index++;
  *((ACE_UINT16*)&this->packet_data_[index]) = htons(chd_.length_);
  index+=2;
  *((ACE_UINT32*)&this->packet_data_[index]) = htonl(this->ssrc_);
  index+=4;

  local_block_ptr = this->rr_;
  while (local_block_ptr)
    {
      *((ACE_UINT32*)&this->packet_data_[index]) = htonl(local_block_ptr->ssrc_);
      index+=4;
      ACE_UINT32 temp = htonl((local_block_ptr->fraction_&0xff) << 24) &