ackheader.hh

COPE the first practical network coding scheme which is developped on click

/* Header to ack encoded packet, implemented in the style of srcr packets */

#ifndef CLICK_ENC_ACK_HH
#define CLICK_ENC_ACK_HH

#include <clicknet/ip.h>

// packet format
CLICK_SIZE_PACKED_STRUCTURE(
struct click_enc_ack {,


  uint8_t    _nentries;              // length of this header in terms of number of ack entries
  uint16_t _et_next;                  // Ethtype of the next packet
  
  /* neighbour id */
  /* highest magic_seq */
  uint8_t    _nb;
  uint16_t   _seq;
  uint8_t _bmap;



  // all methods below adapted from srpacket.hh
  void set_entry(int entry_index, uint8_t nb_id, uint16_t seqno, uint8_t bmap) {
    uint8_t *ndx = (uint8_t *) (this+1);
    ndx += (entry_index - 1) * 4;
    ndx[0] = nb_id;
    
    uint16_t *seq = (uint16_t *)(ndx + 1); 
    seq[0] = htons(seqno);
    ndx[3] = bmap;
  }

  uint8_t get_entry_nb(int entry_index) {
    uint8_t *ndx = (uint8_t *) (this+1);
    ndx += (entry_index - 1) * 4;
    return ndx[0];
  }

  uint16_t get_entry_seq(int entry_index) {
    uint8_t *ndx = (uint8_t *) (this+1);
    ndx += (entry_index - 1) * 4;
    
    uint16_t *seq = (uint16_t *)(ndx + 1); 
    return ntohs(seq[0]);
  }

  uint8_t get_entry_bmap(int entry_index) {
    uint8_t *ndx = (uint8_t *) (this+1);
    ndx += (entry_index - 1) * 4;
    return ndx[3];
  }

  void set_nentries(int n) {
    _nentries = n;
  }


  static size_t get_hlen(int nentries) {
    return sizeof(struct click_enc_ack) + sizeof(uint8_t) * nentries + sizeof(uint16_t) * nentries + sizeof(uint8_t) * nentries - 4;
  }

  size_t nentries() {
    return _nentries;
  }


});

#endif