X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/b0144c1bbe7c2d53b5255f44e176a4e57f6c3a30..1169bd863a0a7a8c9a49039e4dd1a9860845cf1d:/lisp/timer.el

diff --git a/lisp/timer.el b/lisp/timer.el
index 68a9e105da..3131fe3c17 100644
--- a/lisp/timer.el
+++ b/lisp/timer.el
@@ -1,4 +1,4 @@
-;;; timer.el --- run a function with args at some time in future.
+;;; timer.el --- run a function with args at some time in future
 
 ;; Copyright (C) 1996 Free Software Foundation, Inc.
 
@@ -45,7 +45,7 @@
 (defun timer-set-time (timer time &optional delta)
   "Set the trigger time of TIMER to TIME.
 TIME must be in the internal format returned by, e.g., `current-time'.
-If optional third argument DELTA is a non-zero integer, make the timer
+If optional third argument DELTA is a positive number, make the timer
 fire repeatedly that many seconds apart."
   (or (timerp timer)
       (error "Invalid timer"))
@@ -116,16 +116,18 @@ SECS may be a fraction."
     (setq low (+ low (floor secs)))
 
     ;; Normalize
-    (setq low (+ low (/ micro 1000000)))
+    ;; `/' rounds towards zero while `mod' returns a positive number,
+    ;; so we can't rely on (= a (+ (* 100 (/ a 100)) (mod a 100))).
+    (setq low (+ low (/ micro 1000000) (if (< micro 0) -1 0)))
     (setq micro (mod micro 1000000))
-    (setq high (+ high (/ low 65536)))
+    (setq high (+ high (/ low 65536) (if (< low 0) -1 0)))
     (setq low (logand low 65535))
 
     (list high low (and (/= micro 0) micro))))
 
 (defun timer-inc-time (timer secs &optional usecs)
   "Increment the time set in TIMER by SECS seconds and USECS microseconds.
-SECS may be a fraction."
+SECS may be a fraction.  If USECS is omitted, that means it is zero."
   (let ((time (timer-relative-time
 	       (list (aref timer 1) (aref timer 2) (aref timer 3))
 	       secs
@@ -135,17 +137,21 @@ SECS may be a fraction."
     (aset timer 3 (or (nth 2 time) 0))))
 
 (defun timer-set-time-with-usecs (timer time usecs &optional delta)
-  "Set the trigger time of TIMER to TIME.
+  "Set the trigger time of TIMER to TIME plus USECS.
 TIME must be in the internal format returned by, e.g., `current-time'.
-If optional third argument DELTA is a non-zero integer, make the timer
+The microsecond count from TIME is ignored, and USECS is used instead.
+If optional fourth argument DELTA is a positive number, make the timer
 fire repeatedly that many seconds apart."
   (or (timerp timer)
       (error "Invalid timer"))
-  (aset timer 1 (car time))
-  (aset timer 2 (if (consp (cdr time)) (car (cdr time)) (cdr time)))
+  (aset timer 1 (nth 0 time))
+  (aset timer 2 (nth 1 time))
   (aset timer 3 usecs)
   (aset timer 4 (and (numberp delta) (> delta 0) delta))
   timer)
+(make-obsolete 'timer-set-time-with-usecs
+               "use `timer-set-time' and `timer-inc-time' instead."
+               "21.4")
 
 (defun timer-set-function (timer function &optional args)
   "Make TIMER call FUNCTION with optional ARGS when triggering."
@@ -183,8 +189,11 @@ fire repeatedly that many seconds apart."
 	nil)
     (error "Invalid or uninitialized timer")))
 
-(defun timer-activate-when-idle (timer)
-  "Arrange to activate TIMER whenever Emacs is next idle."
+(defun timer-activate-when-idle (timer &optional dont-wait)
+  "Arrange to activate TIMER whenever Emacs is next idle.
+If optional argument DONT-WAIT is non-nil, then enable the
+timer to activate immediately, or at the right time, if Emacs
+is already idle."
   (if (and (timerp timer)
 	   (integerp (aref timer 1))
 	   (integerp (aref timer 2))
@@ -206,7 +215,7 @@ fire repeatedly that many seconds apart."
 	(if last
 	    (setcdr last (cons timer timers))
 	  (setq timer-idle-list (cons timer timers)))
-	(aset timer 0 t)
+	(aset timer 0 (not dont-wait))
 	(aset timer 7 t)
 	nil)
     (error "Invalid or uninitialized timer")))
@@ -264,10 +273,6 @@ This function is called, by name, directly by the C code."
 	(progn
 	  ;; Delete from queue.
 	  (cancel-timer timer)
-	  ;; Run handler
-	  (condition-case nil
-	      (apply (aref timer 5) (aref timer 6))
-	    (error nil))
 	  ;; Re-schedule if requested.
 	  (if (aref timer 4)
 	      (if (aref timer 7)
@@ -282,7 +287,13 @@ This function is called, by name, directly by the C code."
 				      (aref timer 4))))
 		      (if (> repeats timer-max-repeats)
 			  (timer-inc-time timer (* (aref timer 4) repeats)))))
-		(timer-activate timer))))
+		(timer-activate timer)))
+	  ;; Run handler.
+	  ;; We do this after rescheduling so that the handler function
+	  ;; can cancel its own timer successfully with cancel-timer.
+	  (condition-case nil
+	      (apply (aref timer 5) (aref timer 6))
+	    (error nil)))
       (error "Bogus timer event"))))
 
 ;; This function is incompatible with the one in levents.el.
@@ -368,9 +379,11 @@ This function is for compatibility; see also `run-with-timer'."
 ;;;###autoload
 (defun run-with-idle-timer (secs repeat function &rest args)
   "Perform an action the next time Emacs is idle for SECS seconds.
-If REPEAT is non-nil, do this each time Emacs is idle for SECS seconds.
-SECS may be an integer or a floating point number.
 The action is to call FUNCTION with arguments ARGS.
+SECS may be an integer or a floating point number.
+
+If REPEAT is non-nil, do the action each time Emacs has been idle for
+exactly SECS seconds (that is, only once for each time Emacs becomes idle).
 
 This function returns a timer object which you can use in `cancel-timer'."
   (interactive