qp.el (quoted-printable-decode-region): Decode multiple bytes at once.

lisp/gnus/ChangeLog

+2012-08-30  Kenichi Handa  <handa@gnu.org>
+
+	* qp.el (quoted-printable-decode-region): Decode multiple bytes at
+	once.
+
 2012-08-29  Julien Danjou  <julien@danjou.info>
 	* gnus-notifications.el: New file.

lisp/gnus/qp.el

@@ -53,7 +53,10 @@ them into characters should be done separately."
       ;; or both of which are lowercase letters in "abcdef", is
       ;; formally illegal. A robust implementation might choose to
       ;; recognize them as the corresponding uppercase letters.''
-      (let ((case-fold-search t))
+      (let ((case-fold-search t)
+	    (decode-hex #'(lambda (n1 n2)
+			    (+ (* (if (<= n1 ?9) (- n1 ?0) (+ (- n1 ?A) 10)) 16)
+			       (if (<= n2 ?9) (- n2 ?0) (+ (- n2 ?A) 10))))))
 	(narrow-to-region from to)
 	;; Do this in case we're called from Gnus, say, in a buffer
 	;; which already contains non-ASCII characters which would
@@ -65,12 +68,17 @@ them into characters should be done separately."
 		    (not (eobp)))
 	  (cond ((eq (char-after (1+ (point))) ?\n)
 		 (delete-char 2))
-		((looking-at "=[0-9A-F][0-9A-F]")
-		 (let ((byte (string-to-number (buffer-substring (1+ (point))
-							      (+ 3 (point)))
-					    16)))
-		   (mm-insert-byte byte 1)
-		   (delete-char 3)))
+		((looking-at "\\(=[0-9A-F][0-9A-F]\\)+")
+		 ;; Decode this sequence at once; i.e. by a single
+		 ;; deletion and insertion.
+		 (let* ((n (/ (- (match-end 0) (point)) 3))
+			(str (make-string n 0)))
+		   (dotimes (i n)
+		     (aset str i (funcall decode-hex (char-after (1+ (point)))
+					  (char-after (+ 2 (point)))))
+		     (forward-char 3))
+		   (delete-region (match-beginning 0) (match-end 0))
+		   (insert str)))
 		(t
 		 (message "Malformed quoted-printable text")
 		 (forward-char)))))