1 files changed, 35 insertions, 0 deletions

diff --git a/lisp/emacs-lisp/copyright.el b/lisp/emacs-lisp/copyright.el
index 3d160f54606..dcb68188383 100644
--- a/lisp/emacs-lisp/copyright.el
+++ b/lisp/emacs-lisp/copyright.el
@@ -178,6 +178,41 @@ version \\([0-9]+\\), or (at"
 
 
 ;;;###autoload
+(defun copyright-fix-years ()
+  "Convert 2 digit years to 4 digit years.
+Uses heuristic: year >= 50 means 19xx, < 50 means 20xx."
+  (interactive)
+  (widen)
+  (goto-char (point-min))
+  (if (re-search-forward copyright-regexp (+ (point) copyright-limit) t)
+      (let ((s (match-beginning 2)) (e (make-marker))
+            last)
+        (set-marker e (1+ (match-end 2)))
+        (goto-char s)
+        (while (and (< (point) (marker-position e))
+                    (re-search-forward "\\([^0-9]\\)\\([0-9]+\\)[^0-9]"
+                                       (marker-position e) t))
+          (let ((p (point))
+                (sep (match-string 1))
+                (year (string-to-number (match-string 2))))
+            (goto-char (1+ (match-beginning 0)))
+            (unless (= (char-syntax (string-to-char sep)) ?\s)
+              (insert " "))
+            (if (< year 100)
+                (insert (if (>= year 50) "19" "20")))
+            (goto-char p)
+            (setq last p)))
+        (when last
+          (goto-char last)
+          (let ((fill-prefix "     "))
+            (fill-region s last))
+          )
+        (set-marker e nil)
+        (copyright-update nil t))
+    (message "No copyright message")
+    (goto-char (point-min))))
+
+;;;###autoload
 (define-skeleton copyright
   "Insert a copyright by $ORGANIZATION notice at cursor."
   "Company: "