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Diff for /embedaddon/quagga/lib/checksum.c between versions 1.1.1.1 and 1.1.1.2

version 1.1.1.1, 2012/02/21 17:26:12 version 1.1.1.2, 2013/07/21 23:54:39
Line 51  in_cksum(void *parg, int nbytes) Line 51  in_cksum(void *parg, int nbytes)
   
 /* To be consistent, offset is 0-based index, rather than the 1-based   /* To be consistent, offset is 0-based index, rather than the 1-based 
    index required in the specification ISO 8473, Annex C.1 */     index required in the specification ISO 8473, Annex C.1 */
   /* calling with offset == FLETCHER_CHECKSUM_VALIDATE will validate the checksum
      without modifying the buffer; a valid checksum returns 0 */
 u_int16_t  u_int16_t
 fletcher_checksum(u_char * buffer, const size_t len, const uint16_t offset)  fletcher_checksum(u_char * buffer, const size_t len, const uint16_t offset)
 {  {
Line 62  fletcher_checksum(u_char * buffer, const size_t len, c Line 64  fletcher_checksum(u_char * buffer, const size_t len, c
       
   checksum = 0;    checksum = 0;
   
   assert (offset < len);  
   
  /*  if (offset != FLETCHER_CHECKSUM_VALIDATE)
   * Zero the csum in the packet.    /* Zero the csum in the packet. */
   */    {
  csum = (u_int16_t *) (buffer + offset);      assert (offset < (len - 1)); /* account for two bytes of checksum */
  *(csum) = 0;      csum = (u_int16_t *) (buffer + offset);
       *(csum) = 0;
     }
   
   p = buffer;    p = buffer;
   c0 = 0;    c0 = 0;
Line 89  fletcher_checksum(u_char * buffer, const size_t len, c Line 92  fletcher_checksum(u_char * buffer, const size_t len, c
   
       left -= partial_len;        left -= partial_len;
     }      }
  
   /* The cast is important, to ensure the mod is taken as a signed value. */    /* The cast is important, to ensure the mod is taken as a signed value. */
   x = (int)((len - offset - 1) * c0 - c1) % 255;    x = (int)((len - offset - 1) * c0 - c1) % 255;
   
Line 98  fletcher_checksum(u_char * buffer, const size_t len, c Line 101  fletcher_checksum(u_char * buffer, const size_t len, c
   y = 510 - c0 - x;    y = 510 - c0 - x;
   if (y > 255)      if (y > 255)  
     y -= 255;      y -= 255;
     
   /*  
    * Now we write this to the packet.  
    * We could skip this step too, since the checksum returned would  
    * be stored into the checksum field by the caller.  
    */  
   buffer[offset] = x;  
   buffer[offset + 1] = y;  
   
  /* Take care of the endian issue */  if (offset == FLETCHER_CHECKSUM_VALIDATE)
  checksum = htons((x << 8) | (y & 0xFF));    {
       checksum = (c1 << 8) + c0;
     }
   else
     {
       /*
        * Now we write this to the packet.
        * We could skip this step too, since the checksum returned would
        * be stored into the checksum field by the caller.
        */
       buffer[offset] = x;
       buffer[offset + 1] = y;
 
       /* Take care of the endian issue */
       checksum = htons((x << 8) | (y & 0xFF));
     }
   
   return checksum;    return checksum;
 }  }
Removed from v.1.1.1.1  
changed lines
  Added in v.1.1.1.2

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