checksum.lisp

   1 ;;;; $Id: checksum.lisp,v 1.2 2007/12/20 16:32:00 xach Exp $
   2
   3 (in-package #:salza2)
   4
   5 (defclass checksum () ())
   6
   7 (defgeneric update (checksum buffer start count)
   8   (:documentation "Update the CHECKSUM object with COUNT octets
   9   from BUFFER, starting from START."))
  10
  11 (defgeneric result (checksum)
  12   (:documentation "Return the result of CHECKSUM as an integer."))
  13
  14 (defgeneric result-octets (checksum)
  15   (:documentation "Return the result of CHECKSUM as a list of
  16   octets, in MSB order."))
  17
  18 (defun ub32-octets (result)
  19   (list (ldb (byte 8 24) result)
  20         (ldb (byte 8 16) result)
  21         (ldb (byte 8  8) result)
  22         (ldb (byte 8  0) result)))