}

Ptr<Packet>

DsrRouting::IncreasePacketRequestId (Ptr<Packet> packet)

{

  Ptr<Packet> p = packet->Copy ();

  DsrRoutingHeader dsrHeader;

  p->RemoveHeader (dsrHeader);          // Remove the DSR header in whole

  uint32_t offset = dsrHeader.GetDsrOptionsOffset ();   // Get the offset for option header, 8 bytes in this case

  // Remove dsr routing header

  packet->RemoveAtStart (offset);

  Ptr<Packet> returnedPacket = Create<Packet> ();

  // prepare for obtaining rreq header

  uint8_t buf[2];

  packet->CopyData (buf, sizeof(buf));

  uint8_t numberAddress = (buf[1] - 6) / 4;

  DsrOptionRreqHeader rreq;

  rreq.SetNumberAddress (numberAddress);

  packet->RemoveHeader (rreq);

  // Recreate set of headers starting from routing header

  DsrRoutingHeader dsrRoutingHeader;

  dsrRoutingHeader.SetNextHeader (dsrHeader.GetNextHeader());

  dsrRoutingHeader.SetMessageType (dsrHeader.GetMessageType());

  dsrRoutingHeader.SetSourceId (dsrHeader.GetSourceId());

  dsrRoutingHeader.SetDestId (dsrHeader.GetDestId());

  // recreate rreq header

  DsrOptionRreqHeader rreqHeader;

  rreqHeader.AddNodeAddress (m_mainAddress);    // Add our own address in the header

  rreqHeader.SetTarget (rreq.GetTarget());

  m_requestId = m_rreqTable->CheckUniqueRreqId (rreq.GetTarget());      // Check the Id cache for duplicate ones

  rreqHeader.SetId(m_requestId);        // assign new request ID

  // in case there is an error header, also add it to the set of copied headers

  if (packet->GetSize())

    {

      NS_LOG_DEBUG("Error header included");

      DsrOptionRerrUnreachHeader rerr;  // recreate error header

      packet->RemoveHeader(rerr);

      DsrOptionRerrUnreachHeader newUnreach;

      newUnreach.SetErrorType (rerr.GetErrorType());

      newUnreach.SetErrorSrc (rerr.GetErrorSrc());

      newUnreach.SetUnreachNode (rerr.GetUnreachNode());

      newUnreach.SetErrorDst (rerr.GetErrorDst());

      newUnreach.SetSalvage (rerr.GetSalvage ()); // Set the value about whether to salvage a packet or not

      uint16_t length = rreq.GetLength () + newUnreach.GetLength ();

      dsrRoutingHeader.SetPayloadLength (length + 4);

      dsrRoutingHeader.AddDsrOption (rreq);

      dsrRoutingHeader.AddDsrOption (newUnreach);

    }

  else

    {

      dsrRoutingHeader.AddDsrOption (rreqHeader);                      // Add the rreqHeader to the dsr extension header

      uint8_t length = rreqHeader.GetLength ();

      dsrRoutingHeader.SetPayloadLength (uint16_t (length) + 2);

    }

  returnedPacket->AddHeader (dsrRoutingHeader);

  return returnedPacket;