Use a new function to mark anniversaries in Org diary files

* lisp/org-agenda.el (org-agenda-add-entry-to-org-agenda-diary-file):
Use stable internal `org-anniversary' instead of diary-anniversary.
(org-class): New function.
(org-diary-class): Use `org-class'.
(org-anniversary, org-cyclic, org-date, org-block): New functions.

This patch provides stable alternatives for a number of diary
functions to be used in diary sexp entries. The corresponding diary-*
functions swap around their input arguments depending on
`calendar-date-style', which is unstable and evil.  The functions
provided here have a fixed order of arguments, the ISO order: year
month day.

Also, the `i a' key in the agenda now uses `org-anniversary' instead of
diary-anniversary.

lisp/org-agenda.el

@@ -4816,19 +4816,40 @@ This function is invoked if `org-agenda-todo-ignore-deadlines',
 	    (push txt ee)))))
     (nreverse ee)))
 
-(defun org-diary-class (m1 d1 y1 m2 d2 y2 dayname &rest skip-weeks)
+;; Calendar sanity: define some functions that are independent of
+;; `calendar-date-style'.
+;; Normally I would like to use ISO format when calling the diary functions,
+;; but to make sure we still have Emacs 22 compatibility we bind
+;; also `european-calendar-style' and use european format
+(defun org-anniversary (year month day &optional mark)
+  "Like `diary-anniversary', but with fixed (ISO) order of arguments."
+  (org-no-warnings
+   (let ((calendar-date-style 'european) (european-calendar-style t))
+     (diary-anniversary day month year mark))))
+(defun org-cyclic (N year month day &optional mark)
+  "Like `diary-cyclic', but with fixed (ISO) order of arguments."
+  (org-no-warnings
+   (let ((calendar-date-style 'european)	(european-calendar-style t))
+     (diary-cyclic N day month year mark))))
+(defun org-block (Y1 M1 D1 Y2 M2 D2 &optional mark)
+  "Like `diary-block', but with fixed (ISO) order of arguments."
+  (org-no-warnings
+   (let ((calendar-date-style 'european)	(european-calendar-style t))
+     (diary-block D1 M1 Y1 D2 M2 Y2 mark))))
+(defun org-date (year month day &optional mark)
+  "Like `diary-date', but with fixed (ISO) order of arguments."
+  (org-no-warnings
+   (let ((calendar-date-style 'european)	(european-calendar-style t))
+     (diary-date day month year mark))))
+
+;; Define the` org-class' function
+(defun org-class (y1 m1 d1 y2 m2 d2 dayname &rest skip-weeks)
   "Entry applies if date is between dates on DAYNAME, but skips SKIP-WEEKS.
-The order of the first 2 times 3 arguments depends on the variable
-`calendar-date-style' or, if that is not defined, on `european-calendar-style'.
-So for American calendars, give this as MONTH DAY YEAR, for European as
-DAY MONTH YEAR, and for ISO as YEAR MONTH DAY.
 DAYNAME is a number between 0 (Sunday) and 6 (Saturday).  SKIP-WEEKS
 is any number of ISO weeks in the block period for which the item should
 be skipped."
-  (let* ((date1 (calendar-absolute-from-gregorian
-		 (org-order-calendar-date-args m1 d1 y1)))
-	 (date2 (calendar-absolute-from-gregorian
-		 (org-order-calendar-date-args m2 d2 y2)))
+  (let* ((date1 (calendar-absolute-from-gregorian (list m1 d1 y1)))
+	 (date2 (calendar-absolute-from-gregorian (list m2 d2 y2)))
 	 (d (calendar-absolute-from-gregorian date)))
     (and
      (<= date1 d)
@@ -4840,6 +4861,28 @@ be skipped."
 	   (not (member (car (calendar-iso-from-absolute d)) skip-weeks))))
      entry)))
 
+(defun org-diary-class (m1 d1 y1 m2 d2 y2 dayname &rest skip-weeks)
+  "Like `org-class', but honor `calendar-date-style'.
+The order of the first 2 times 3 arguments depends on the variable
+`calendar-date-style' or, if that is not defined, on `european-calendar-style'.
+So for American calendars, give this as MONTH DAY YEAR, for European as
+DAY MONTH YEAR, and for ISO as YEAR MONTH DAY.
+DAYNAME is a number between 0 (Sunday) and 6 (Saturday).  SKIP-WEEKS
+is any number of ISO weeks in the block period for which the item should
+be skipped.
+
+This function is here only for backward compatibility and it is deprecated,
+please use `org-class' instead."
+  (let* ((date1 (calendar-absolute-from-gregorian
+		 (org-order-calendar-date-args m1 d1 y1)))
+	 (date2 (calendar-absolute-from-gregorian
+		 (org-order-calendar-date-args m2 d2 y2)))
+	 (d (calendar-absolute-from-gregorian date)))
+    (org-class
+     (nth 2 date1) (car date1) (nth 1 date1)
+     (nth 2 date2) (car date2) (nth 1 date2)
+     dayname skip-weeks)))
+
 (defalias 'org-get-closed 'org-agenda-get-progress)
 (defun org-agenda-get-progress ()
   "Return the logged TODO entries for agenda display."
@@ -7768,17 +7811,8 @@ the resulting entry will not be shown.  When TEXT is empty, switch to
       (org-back-over-empty-lines)
       (backward-char 1)
       (insert "\n")
-      (require 'diary-lib)
-      (let ((calendar-date-display-form
-	     (if (if (boundp 'calendar-date-style)
-		     (eq calendar-date-style 'european)
-		   (with-no-warnings ;; european-calendar-style is obsolete as of version 23.1
-		     (org-bound-and-true-p european-calendar-style))) ; Emacs 22
-		 '(day " " month " " year)
-	       '(month " " day " " year))))
-
-	(insert (format "%%%%(diary-anniversary %s) %s"
-			(calendar-date-string d1 nil t) text))))
+      (insert (format "%%%%(org-anniversary %d %2d %2d) %s"
+		      (nth 2 d1) (car d1) (nth 1 d1) text)))
      ((eq type 'day)
       (let ((org-prefix-has-time t)
 	    (org-agenda-time-leading-zero t)