-;;; 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.
(aset timer 4 repeat)
timer)
+(defun timer-next-integral-multiple-of-time (time secs)
+ "Yield the next value after TIME that is an integral multiple of SECS.
+More precisely, the next value, after TIME, that is an integral multiple
+of SECS seconds since the epoch. SECS may be a fraction."
+ (let ((time-base (ash 1 16)))
+ (if (fboundp 'atan)
+ ;; Use floating point, taking care to not lose precision.
+ (let* ((float-time-base (float time-base))
+ (million 1000000.0)
+ (time-usec (+ (* million
+ (+ (* float-time-base (nth 0 time))
+ (nth 1 time)))
+ (nth 2 time)))
+ (secs-usec (* million secs))
+ (mod-usec (mod time-usec secs-usec))
+ (next-usec (+ (- time-usec mod-usec) secs-usec))
+ (time-base-million (* float-time-base million)))
+ (list (floor next-usec time-base-million)
+ (floor (mod next-usec time-base-million) million)
+ (floor (mod next-usec million))))
+ ;; Floating point is not supported.
+ ;; Use integer arithmetic, avoiding overflow if possible.
+ (let* ((mod-sec (mod (+ (* (mod time-base secs)
+ (mod (nth 0 time) secs))
+ (nth 1 time))
+ secs))
+ (next-1-sec (+ (- (nth 1 time) mod-sec) secs)))
+ (list (+ (nth 0 time) (floor next-1-sec time-base))
+ (mod next-1-sec time-base)
+ 0)))))
+
(defun timer-relative-time (time secs &optional usecs)
"Advance TIME by SECS seconds and optionally USECS microseconds.
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))))
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))
(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")))
+;;;###autoload
(defalias 'disable-timeout 'cancel-timer)
+;;;###autoload
(defun cancel-timer (timer)
"Remove TIMER from the list of active timers."
(or (timerp timer)
(setq timer-idle-list (delq timer timer-idle-list))
nil)
+;;;###autoload
(defun cancel-function-timers (function)
"Cancel all timers scheduled by `run-at-time' which would run FUNCTION."
(interactive "aCancel timers of function: ")
(setq timer-idle-list (delq (car tail) timer-idle-list)))
(setq tail (cdr tail)))))
\f
-;; Set up the common handler for all timer events. Since the event has
-;; the timer as parameter we can still distinguish. Note that using
-;; special-event-map ensures that event timer events that arrive in the
-;; middle of a key sequence being entered are still handled correctly.
-(define-key special-event-map [timer-event] 'timer-event-handler)
-
;; Record the last few events, for debugging.
(defvar timer-event-last-2 nil)
(defvar timer-event-last-1 nil)
(defvar timer-event-last nil)
-(defun timer-event-handler (event)
- "Call the handler for the timer in the event EVENT."
- (interactive "e")
+(defvar timer-max-repeats 10
+ "*Maximum number of times to repeat a timer, if real time jumps.")
+
+(defun timer-until (timer time)
+ "Calculate number of seconds from when TIMER will run, until TIME.
+TIMER is a timer, and stands for the time when its next repeat is scheduled.
+TIME is a time-list."
+ (let ((high (- (car time) (aref timer 1)))
+ (low (- (nth 1 time) (aref timer 2))))
+ (+ low (* high 65536))))
+
+(defun timer-event-handler (timer)
+ "Call the handler for the timer TIMER.
+This function is called, by name, directly by the C code."
(setq timer-event-last-2 timer-event-last-1)
(setq timer-event-last-1 timer-event-last)
- (setq timer-event-last (cons event (copy-sequence event)))
- (let ((inhibit-quit t)
- (timer (car-safe (cdr-safe event))))
+ (setq timer-event-last timer)
+ (let ((inhibit-quit t))
(if (timerp timer)
(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)
(timer-activate-when-idle timer)
(timer-inc-time timer (aref timer 4) 0)
- (timer-activate timer))))
+ ;; If real time has jumped forward,
+ ;; perhaps because Emacs was suspended for a long time,
+ ;; limit how many times things get repeated.
+ (if (and (numberp timer-max-repeats)
+ (< 0 (timer-until timer (current-time))))
+ (let ((repeats (/ (timer-until timer (current-time))
+ (aref timer 4))))
+ (if (> repeats timer-max-repeats)
+ (timer-inc-time timer (* (aref timer 4) repeats)))))
+ (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.
"Perform an action at time TIME.
Repeat the action every REPEAT seconds, if REPEAT is non-nil.
TIME should be a string like \"11:23pm\", nil meaning now, a number of seconds
-from now, or a value from `encode-time'.
+from now, a value from `current-time', or t (with non-nil REPEAT)
+meaning the next integral multiple of REPEAT.
REPEAT may be an integer or floating point number.
The action is to call FUNCTION with arguments ARGS.
This function returns a timer object which you can use in `cancel-timer'."
(interactive "sRun at time: \nNRepeat interval: \naFunction: ")
+ (or (null repeat)
+ (and (numberp repeat) (< 0 repeat))
+ (error "Invalid repetition interval"))
+
;; Special case: nil means "now" and is useful when repeating.
(if (null time)
(setq time (current-time)))
+ ;; Special case: t means the next integral multiple of REPEAT.
+ (if (and (eq time t) repeat)
+ (setq time (timer-next-integral-multiple-of-time (current-time) repeat)))
+
;; Handle numbers as relative times in seconds.
(if (numberp time)
(setq time (timer-relative-time (current-time) time)))
(or (consp time)
(error "Invalid time format"))
- (or (null repeat)
- (numberp repeat)
- (error "Invalid repetition interval"))
-
(let ((timer (timer-create)))
(timer-set-time timer time repeat)
(timer-set-function timer function args)
;;;###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