[movitz-cvs] CVS update: movitz/losp/lib/net/ip4.lisp

[Frode Vatvedt Fjeld]

Update of /project/movitz/cvsroot/movitz/losp/lib/net
In directory common-lisp.net:/tmp/cvs-serv19491

Modified Files:
	ip4.lisp 
Log Message:
Have checksum-ok accept any number of checksum terms, since typically
there will be a frew terms from the pseudo-header and one term from
the actual packet.

Date: Wed Nov 24 15:22:57 2004
Author: ffjeld

Index: movitz/losp/lib/net/ip4.lisp
diff -u movitz/losp/lib/net/ip4.lisp:1.10 movitz/losp/lib/net/ip4.lisp:1.11
--- movitz/losp/lib/net/ip4.lisp:1.10	Wed Nov 24 14:12:26 2004
+++ movitz/losp/lib/net/ip4.lisp	Wed Nov 24 15:22:57 2004
@@ -10,7 +10,7 @@
 ;;;; Author:        Frode Vatvedt Fjeld <frodef at acm.org>
 ;;;; Created at:    Wed Apr 30 13:52:57 2003
 ;;;;                
-;;;; $Id: ip4.lisp,v 1.10 2004/11/24 13:12:26 ffjeld Exp $
+;;;; $Id: ip4.lisp,v 1.11 2004/11/24 14:22:57 ffjeld Exp $
 ;;;;                
 ;;;;------------------------------------------------------------------
 
@@ -112,10 +112,12 @@
     (setf (ip4-ref packet start 10 :unsigned-byte16) checksum)))
   packet)
 
-(defun checksum-ok (x)
-  (= #xffff
-     (+ (ldb (byte 16 0) x)
-	(ash x -16))))
+(defun checksum-ok (x &rest more-xes)
+  (declare (dynamic-extent more-xes))
+  (let ((x (reduce #'add-u16-ones-complement more-xes :initial-value x)))
+    (= #xffff
+       (+ (ldb (byte 16 0) x)
+	  (ash x -16)))))
 
 (defun ip-input (stack packet start)
   (let ((header-size (* 4 (ip-header-length packet start))))