1 ;;; Interval timers for GNU Emacs
2 ;;; Copyright (C) 1988, 1991, 1993, 1997, 1998 Kyle E. Jones
4 ;;; This program is free software; you can redistribute it and/or modify
5 ;;; it under the terms of the GNU General Public License as published by
6 ;;; the Free Software Foundation; either version 2, or (at your option)
9 ;;; This program is distributed in the hope that it will be useful,
10 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
11 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 ;;; GNU General Public License for more details.
14 ;;; A copy of the GNU General Public License can be obtained from this
15 ;;; program's author (send electronic mail to kyle@uunet.uu.net) or from
16 ;;; the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA
19 ;;; Send bug reports to kyle_jones@wonderworks.com
23 (require 'lisp-float-type)
25 ;; `itimer' feature means Emacs-Lisp programmers get:
31 ;; itimer-uses-arguments
32 ;; itimer-function-arguments
35 ;; set-itimer-function
36 ;; set-itimer-uses-arguments
37 ;; set-itimer-function-arguments
44 ;; Interactive users get these commands:
49 ;; See the doc strings of these functions for more information.
51 (defvar itimer-version "1.09"
52 "Version number of the itimer package.")
54 (defvar itimer-list nil
55 "List of all active itimers.")
57 (defvar itimer-process nil
58 "Process that drives all itimers, if a subprocess is being used.")
60 (defvar itimer-timer nil
61 "Emacs internal timer that drives the itimer system, if a subprocess
62 is not being used to drive the system.")
64 (defvar itimer-timer-last-wakeup nil
65 "The time the timer driver function last ran.")
67 (defvar itimer-short-interval 1e-3
68 "Interval used for scheduling an event a very short time in the future.
69 Used internally to make the scheduler wake up early.
72 ;; This value is maintained internally; it does not determine
73 ;; itimer granularity. Itimer granularity is 1 second if your
74 ;; Emacs doesn't support floats or your system doesn't have a
75 ;; clock with microsecond granularity. Otherwise granularity is
76 ;; to the microsecond, although you can't possibly get timers to be
77 ;; executed with this kind of accuracy in practice. There will
78 ;; be delays due to system and Emacs internal activity that delay
79 ;; dealing with synchronous events and process output.
80 (defvar itimer-next-wakeup itimer-short-interval
81 "Itimer process will wakeup to service running itimers within this
84 (defvar itimer-edit-map nil
85 "Keymap used when in Itimer Edit mode.")
89 (setq itimer-edit-map (make-sparse-keymap))
90 (define-key itimer-edit-map "s" 'itimer-edit-set-field)
91 (define-key itimer-edit-map "d" 'itimer-edit-delete-itimer)
92 (define-key itimer-edit-map "q" 'itimer-edit-quit)
93 (define-key itimer-edit-map "\t" 'itimer-edit-next-field)
94 (define-key itimer-edit-map " " 'next-line)
95 (define-key itimer-edit-map "n" 'next-line)
96 (define-key itimer-edit-map "p" 'previous-line)
97 (define-key itimer-edit-map "\C-?" 'itimer-edit-previous-field)
98 (define-key itimer-edit-map "x" 'start-itimer)
99 (define-key itimer-edit-map "?" 'itimer-edit-help))
101 (defvar itimer-inside-driver nil)
103 (defvar itimer-edit-start-marker nil)
105 ;; macros must come first... or byte-compile'd code will throw back its
108 (defmacro itimer-decrement (variable)
109 (list 'setq variable (list '1- variable)))
111 (defmacro itimer-increment (variable)
112 (list 'setq variable (list '1+ variable)))
114 (defmacro itimer-signum (n)
115 (list 'if (list '> n 0) 1
116 (list 'if (list 'zerop n) 0 -1)))
118 ;; Itimer access functions should behave as if they were subrs. These
119 ;; macros are used to check the arguments to the itimer functions and
120 ;; signal errors appropriately if the arguments are not valid.
122 (defmacro check-itimer (var)
123 "If VAR is not bound to an itimer, signal `wrong-type-argument'.
126 (list 'if (list 'itimerp var) var
127 (list 'signal ''wrong-type-argument
128 (list 'list ''itimerp var)))))
130 (defmacro check-itimer-coerce-string (var)
131 "If VAR is not bound to a string, look up the itimer that it names and
132 bind VAR to it. Otherwise, if VAR is not bound to an itimer, signal
133 wrong-type-argument. This is a macro."
136 (list (list 'itimerp var) var)
137 (list (list 'stringp var) (list 'get-itimer var))
138 (list t (list 'signal ''wrong-type-argument
139 (list 'list ''string-or-itimer-p var))))))
141 (defmacro check-nonnegative-number (var)
142 "If VAR is not bound to a number, signal `wrong-type-argument'.
143 If VAR is not bound to a positive number, signal args-out-of-range.
146 (list 'if (list 'not (list 'numberp var))
147 (list 'signal ''wrong-type-argument
148 (list 'list ''natnump var))
149 (list 'if (list '< var 0)
150 (list 'signal ''args-out-of-range (list 'list var))
153 (defmacro check-string (var)
154 "If VAR is not bound to a string, signal `wrong-type-argument'.
157 (list 'if (list 'stringp var) var
158 (list 'signal ''wrong-type-argument
159 (list 'list ''stringp var)))))
161 ;; Functions to access and modify itimer attributes.
163 (defun itimerp (object)
164 "Return non-nil if OBJECT is an itimer."
165 (and (consp object) (eq (length object) 8)))
167 (defun itimer-live-p (object)
168 "Return non-nil if OBJECT is an itimer and is active.
169 ``Active'' means Emacs will run it when it expires.
170 `activate-itimer' must be called on an itimer to make it active.
171 Itimers started with `start-itimer' are automatically active."
172 (and (itimerp object) (memq object itimer-list)))
174 (defun itimer-name (itimer)
175 "Return the name of ITIMER."
176 (check-itimer itimer)
179 (defun itimer-value (itimer)
180 "Return the number of seconds until ITIMER expires."
181 (check-itimer itimer)
184 (defun itimer-restart (itimer)
185 "Return the value to which ITIMER will be set at restart.
186 The value nil is returned if this itimer isn't set to restart."
187 (check-itimer itimer)
190 (defun itimer-function (itimer)
191 "Return the function of ITIMER.
192 This function is called each time ITIMER expires."
193 (check-itimer itimer)
196 (defun itimer-is-idle (itimer)
197 "Return non-nil if ITIMER is an idle timer.
198 Normal timers expire after a set interval. Idle timers expire
199 only after Emacs has been idle for a specific interval. ``Idle''
200 means no command events have occurred within the interval."
201 (check-itimer itimer)
204 (defun itimer-uses-arguments (itimer)
205 "Return non-nil if the function of ITIMER will be called with arguments.
206 ITIMER's function is called with the arguments each time ITIMER expires.
207 The arguments themselves are retrievable with `itimer-function-arguments'."
208 (check-itimer itimer)
211 (defun itimer-function-arguments (itimer)
212 "Return the function arguments of ITIMER as a list.
213 ITIMER's function is called with these arguments each time ITIMER expires."
214 (check-itimer itimer)
217 (defun itimer-recorded-run-time (itimer)
218 (check-itimer itimer)
221 (defun set-itimer-value (itimer value)
222 "Set the timeout value of ITIMER to be VALUE.
223 Itimer will expire in this many seconds.
224 If your version of Emacs supports floating point numbers then
225 VALUE can be a floating point number. Otherwise it
228 (check-itimer itimer)
229 (check-nonnegative-number value)
230 (let ((inhibit-quit t))
231 ;; If the itimer is in the active list, and under the new
232 ;; timeout value would expire before we would normally
233 ;; wakeup, wakeup now and recompute a new wakeup time.
234 (or (and (< value itimer-next-wakeup)
235 (and (itimer-name itimer) (get-itimer (itimer-name itimer)))
236 (progn (itimer-driver-wakeup)
237 (setcar (cdr itimer) value)
238 (itimer-driver-wakeup)
240 (setcar (cdr itimer) value))
243 ;; Same as set-itimer-value but does not wakeup the driver.
244 ;; Only should be used by the drivers when processing expired timers.
245 (defun set-itimer-value-internal (itimer value)
246 (check-itimer itimer)
247 (check-nonnegative-number value)
248 (setcar (cdr itimer) value))
250 (defun set-itimer-restart (itimer restart)
251 "Set the restart value of ITIMER to be RESTART.
252 If RESTART is nil, ITIMER will not restart when it expires.
253 If your version of Emacs supports floating point numbers then
254 RESTART can be a floating point number. Otherwise it
257 (check-itimer itimer)
258 (if restart (check-nonnegative-number restart))
259 (setcar (cdr (cdr itimer)) restart))
261 (defun set-itimer-function (itimer function)
262 "Set the function of ITIMER to be FUNCTION.
263 FUNCTION will be called when itimer expires.
265 (check-itimer itimer)
266 (setcar (nthcdr 3 itimer) function))
268 (defun set-itimer-is-idle (itimer flag)
269 "Set flag that says whether ITIMER is an idle timer.
270 If FLAG is non-nil, then ITIMER will be considered an idle timer.
272 (check-itimer itimer)
273 (setcar (nthcdr 4 itimer) flag))
275 (defun set-itimer-uses-arguments (itimer flag)
276 "Set flag that says whether the function of ITIMER is called with arguments.
277 If FLAG is non-nil, then the function will be called with one argument,
278 otherwise the function will be called with no arguments.
280 (check-itimer itimer)
281 (setcar (nthcdr 5 itimer) flag))
283 (defun set-itimer-function-arguments (itimer &optional arguments)
284 "Set the function arguments of ITIMER to be ARGUMENTS.
285 The function of ITIMER will be called with ARGUMENTS when itimer expires.
287 (check-itimer itimer)
288 (setcar (nthcdr 6 itimer) arguments))
290 (defun set-itimer-recorded-run-time (itimer time)
291 (check-itimer itimer)
292 (setcar (nthcdr 7 itimer) time))
294 (defun get-itimer (name)
295 "Return itimer named NAME, or nil if there is none."
297 (assoc name itimer-list))
299 (defun read-itimer (prompt &optional initial-input)
300 "Read the name of an itimer from the minibuffer and return the itimer
301 associated with that name. The user is prompted with PROMPT.
302 Optional second arg INITIAL-INPUT non-nil is inserted into the
303 minibuffer as initial user input."
304 (get-itimer (completing-read prompt itimer-list nil 'confirm initial-input)))
306 (defun delete-itimer (itimer)
307 "Deletes ITIMER. ITIMER may be an itimer or the name of one."
308 (check-itimer-coerce-string itimer)
309 (setq itimer-list (delq itimer itimer-list)))
311 (defun start-itimer (name function value &optional restart
312 is-idle with-args &rest function-arguments)
315 NAME, FUNCTION, VALUE &optional RESTART, IS-IDLE, WITH-ARGS, &rest FUNCTION-ARGUMENTS.
316 NAME is an identifier for the itimer. It must be a string. If an itimer
317 already exists with this name, NAME will be modified slightly to make
319 FUNCTION should be a function (or symbol naming one). It
320 will be called each time the itimer expires with arguments of
321 FUNCTION-ARGUMENTS. The function can access the itimer that
322 invoked it through the variable `current-itimer'. If WITH-ARGS
323 is nil then FUNCTION is called with no arguments. This is for
324 backward compatibility with older versions of the itimer
325 package which always called FUNCTION with no arguments.
326 VALUE is the number of seconds until this itimer expires.
327 If your version of Emacs supports floating point numbers then
328 VALUE can be a floating point number. Otherwise it
330 Optional fourth arg RESTART non-nil means that this itimer should be
331 restarted automatically after its function is called. Normally an itimer
332 is deleted at expiration after its function has returned.
333 If non-nil RESTART should be a number indicating the value at which the
334 itimer should be set at restart time.
335 Optional fifth arg IS-IDLE specifies if this is an idle timer.
336 Normal timers expire after a set interval. Idle timers expire
337 only after Emacs has been idle for specific interval. ``Idle''
338 means no command events have occurred within the interval.
339 Returns the newly created itimer."
341 (list (completing-read "Start itimer: " itimer-list)
342 (read (completing-read "Itimer function: " obarray 'fboundp))
344 (while (or (not (numberp value)) (< value 0))
345 (setq value (read-from-minibuffer "Itimer value: " nil nil t)))
348 (while (and restart (or (not (numberp restart)) (< restart 0)))
349 (setq restart (read-from-minibuffer "Itimer restart: "
352 ;; hard to imagine the user specifying these interactively
356 (check-nonnegative-number value)
357 (if restart (check-nonnegative-number restart))
358 ;; Make proposed itimer name unique if it's not already.
361 (while (get-itimer name)
362 (setq name (format "%s<%d>" oname num))
363 (itimer-increment num)))
364 (activate-itimer (list name value restart function is-idle
365 with-args function-arguments (list 0 0 0)))
368 (defun make-itimer ()
369 "Create an unactivated itimer.
370 The itimer will not begin running until activated with `activate-itimer'.
371 Set the itimer's expire interval with `set-itimer-value'.
372 Set the itimer's function interval with `set-itimer-function'.
373 Once this is done, the timer can be activated."
374 (list nil 0 nil 'ignore nil nil nil (list 0 0 0)))
376 (defun activate-itimer (itimer)
377 "Activate ITIMER, which was previously created with `make-itimer'.
378 ITIMER will be added to the global list of running itimers,
379 its FUNCTION will be called when it expires, and so on."
380 (check-itimer itimer)
381 (if (memq itimer itimer-list)
382 (error "itimer already activated"))
383 (if (not (numberp (itimer-value itimer)))
384 (error "itimer timeout value not a number: %s" (itimer-value itimer)))
385 (if (<= (itimer-value itimer) 0)
386 (error "itimer timeout value not positive: %s" (itimer-value itimer)))
387 ;; If there's no itimer driver/process, start one now.
388 ;; Otherwise wake up the itimer driver so that seconds slept before
389 ;; the new itimer is created won't be counted against it.
390 (if (or itimer-process itimer-timer)
391 (itimer-driver-wakeup)
392 (itimer-driver-start))
393 ;; Roll a unique name for the timer if it doesn't have a name
395 (if (not (stringp (car itimer)))
396 (let ((name "itimer-0")
399 (while (get-itimer name)
400 (setq name (format "%s<%d>" oname num))
401 (itimer-increment num))
402 (setcar itimer name))
403 ;; signal an error if the timer's name matches an already
405 (if (get-itimer (itimer-name itimer))
406 (error "itimer named \"%s\" already existing and activated"
407 (itimer-name itimer))))
408 (let ((inhibit-quit t))
410 ;; Modify the itimer timeout value as if it were begun
411 ;; at the last time when the itimer driver was woken up.
414 (+ (itimer-value itimer)
415 (itimer-time-difference (current-time)
416 itimer-timer-last-wakeup))))
417 ;; add the itimer to the global list
418 (setq itimer-list (cons itimer itimer-list))
419 ;; If the itimer process is scheduled to wake up too late for
420 ;; the itimer we wake it up to calculate a correct wakeup
421 ;; value giving consideration to the newly added itimer.
422 (if (< (itimer-value itimer) itimer-next-wakeup)
423 (itimer-driver-wakeup))))
425 ;; User level functions to list and modify existing itimers.
426 ;; Itimer Edit major mode, and the editing commands thereof.
428 (defun list-itimers ()
429 "Pop up a buffer containing a list of all itimers.
430 The major mode of the buffer is Itimer Edit mode. This major mode provides
431 commands to manipulate itimers; see the documentation for
432 `itimer-edit-mode' for more information."
434 (let* ((buf (get-buffer-create "*Itimer List*"))
436 (standard-output buf)
437 (itimers (reverse itimer-list)))
440 (setq buffer-read-only nil)
443 "Name Value Restart Function Idle Arguments"
445 "---- ----- ------- -------- ---- --------")
446 (if (null itimer-edit-start-marker)
447 (setq itimer-edit-start-marker (point)))
450 (prin1 (itimer-name (car itimers)))
452 (insert (itimer-truncate-string
453 (format "%5.5s" (itimer-value (car itimers))) 5))
455 (insert (itimer-truncate-string
456 (format "%5.5s" (itimer-restart (car itimers))) 5))
458 (insert (itimer-truncate-string
459 (format "%.19s" (itimer-function (car itimers))) 19))
461 (if (itimer-is-idle (car itimers))
465 (if (itimer-uses-arguments (car itimers))
466 (prin1 (itimer-function-arguments (car itimers)))
468 (setq itimers (cdr itimers)))
471 (if (< (point) itimer-edit-start-marker)
472 (goto-char itimer-edit-start-marker))
473 (setq buffer-read-only t)
474 (display-buffer buf)))
476 (defun edit-itimers ()
477 "Display a list of all itimers and select it for editing.
478 The major mode of the buffer containing the listing is Itimer Edit mode.
479 This major mode provides commands to manipulate itimers; see the documentation
480 for `itimer-edit-mode' for more information."
482 ;; since user is editing, make sure displayed data is reasonably up-to-date
483 (if (or itimer-process itimer-timer)
484 (itimer-driver-wakeup))
486 (select-window (get-buffer-window "*Itimer List*"))
487 (goto-char itimer-edit-start-marker)
492 (message "type q to quit, ? for help"))
494 ;; no point in making this interactive.
495 (defun itimer-edit-mode ()
496 "Major mode for manipulating itimers.
497 Attributes of running itimers are changed by moving the cursor to the
498 desired field and typing `s' to set that field. The field will then be
499 set to the value read from the minibuffer.
502 TAB move forward a field
503 DEL move backward a field
505 d delete the selected itimer
508 (kill-all-local-variables)
509 (make-local-variable 'tab-stop-list)
510 (setq major-mode 'itimer-edit-mode
511 mode-name "Itimer Edit"
513 tab-stop-list '(22 32 40 60 67))
516 (buffer-disable-undo (current-buffer))
517 (use-local-map itimer-edit-map)
518 (set-syntax-table emacs-lisp-mode-syntax-table))
520 (put 'itimer-edit-mode 'mode-class 'special)
522 (defun itimer-edit-help ()
523 "Help function for Itimer Edit."
525 (if (eq last-command 'itimer-edit-help)
527 (message "TAB, DEL select fields, (s)et field, (d)elete itimer (type ? for more help)")))
529 (defun itimer-edit-quit ()
532 (bury-buffer (current-buffer))
534 (switch-to-buffer (other-buffer (current-buffer)))
537 (defun itimer-edit-set-field ()
539 ;; First two lines in list buffer are headers.
540 ;; Cry out against the luser who attempts to change a field there.
541 (if (<= (point) itimer-edit-start-marker)
543 ;; field-value must be initialized to be something other than a
544 ;; number, symbol, or list.
545 (let (itimer field (field-value ""))
546 (setq itimer (save-excursion
547 ;; read the name of the itimer from the beginning of
550 (get-itimer (read (current-buffer))))
551 field (save-excursion
552 (itimer-edit-beginning-of-field)
553 (let ((opoint (point))
555 ;; count the number of sexprs until we reach the cursor
556 ;; and use this info to determine which field the user
559 (while (and (>= opoint (point)) (< n 6))
562 (itimer-increment n))
563 (cond ((eq n 1) (error "Cannot change itimer name."))
568 (t 'function-argument)))))
569 (cond ((eq field 'value)
570 (let ((prompt "Set itimer value: "))
571 (while (not (natnump field-value))
572 (setq field-value (read-from-minibuffer prompt nil nil t)))))
574 (let ((prompt "Set itimer restart: "))
575 (while (and field-value (not (natnump field-value)))
576 (setq field-value (read-from-minibuffer prompt nil nil t)))))
577 ((eq field 'function)
578 (let ((prompt "Set itimer function: "))
579 (while (not (or (and (symbolp field-value) (fboundp field-value))
580 (and (consp field-value)
581 (memq (car field-value) '(lambda macro)))))
583 (read (completing-read prompt obarray 'fboundp nil))))))
585 (setq field-value (not (itimer-is-idle itimer))))
586 ((eq field 'function-argument)
587 (let ((prompt "Set itimer function argument: "))
588 (setq field-value (read-expression prompt))
589 (cond ((not (listp field-value))
590 (setq field-value (list field-value))))
591 (if (null field-value)
592 (set-itimer-uses-arguments itimer nil)
593 (set-itimer-uses-arguments itimer t)))))
594 ;; set the itimer field
595 (funcall (intern (concat "set-itimer-" (symbol-name field)))
597 ;; move to beginning of field to be changed
598 (itimer-edit-beginning-of-field)
599 ;; modify the list buffer to reflect the change.
600 (let (buffer-read-only kill-ring)
602 (kill-region (point) (progn (skip-chars-forward " \t") (point)))
603 (prin1 field-value (current-buffer))
608 (defun itimer-edit-delete-itimer ()
610 ;; First two lines in list buffer are headers.
611 ;; Cry out against the luser who attempts to change a field there.
612 (if (<= (point) itimer-edit-start-marker)
615 (read-itimer "Delete itimer: "
616 (save-excursion (beginning-of-line) (read (current-buffer)))))
617 ;; update list information
620 (defun itimer-edit-next-field (count)
622 (itimer-edit-beginning-of-field)
623 (cond ((> (itimer-signum count) 0)
624 (while (not (zerop count))
626 ;; wrap from eob to itimer-edit-start-marker
629 (goto-char itimer-edit-start-marker)
633 ;; treat fields at beginning of line as if they weren't there.
638 (itimer-decrement count)))
639 ((< (itimer-signum count) 0)
640 (while (not (zerop count))
642 ;; treat fields at beginning of line as if they weren't there.
645 ;; wrap from itimer-edit-start-marker to field at eob.
646 (if (<= (point) itimer-edit-start-marker)
648 (goto-char (point-max))
650 (itimer-increment count)))))
652 (defun itimer-edit-previous-field (count)
654 (itimer-edit-next-field (- count)))
656 (defun itimer-edit-beginning-of-field ()
657 (let ((forw-back (save-excursion (forward-sexp) (backward-sexp) (point)))
658 (back (save-excursion (backward-sexp) (point))))
659 (cond ((eq forw-back back) (backward-sexp))
660 ((eq forw-back (point)) t)
661 (t (backward-sexp)))))
663 (defun itimer-truncate-string (str len)
664 (if (<= (length str) len)
666 (substring str 0 len)))
668 ;; internals of the itimer implementation.
670 (defun itimer-run-expired-timers (time-elapsed)
671 (let ((itimers (copy-sequence itimer-list))
677 ;; process filters can be hit by stray C-g's from the user,
678 ;; so we must protect this stuff appropriately.
679 ;; Quit's are allowed from within itimer functions, but we
680 ;; catch them and print a message.
682 (setq next-wakeup 600)
683 (cond ((and (boundp 'last-command-event-time)
684 (consp last-command-event-time))
685 (setq last-event-time last-command-event-time
686 idle-time (itimer-time-difference (current-time)
688 ((and (boundp 'last-input-time) (consp last-input-time))
689 (setq last-event-time (list (car last-input-time)
690 (cdr last-input-time)
692 idle-time (itimer-time-difference (current-time)
694 ;; no way to do this under FSF Emacs yet.
695 (t (setq last-event-time '(0 0 0)
698 (setq itimer (car itimers))
699 (if (itimer-is-idle itimer)
700 (setq recorded-run-time (itimer-recorded-run-time itimer))
701 (set-itimer-value-internal itimer (max 0 (- (itimer-value itimer)
703 (if (if (itimer-is-idle itimer)
704 (or (> (itimer-time-difference recorded-run-time
707 (< idle-time (itimer-value itimer)))
708 (> (itimer-value itimer) 0))
710 (if (itimer-is-idle itimer)
711 (if (< idle-time (itimer-value itimer))
712 (min next-wakeup (- (itimer-value itimer) idle-time))
713 (min next-wakeup (itimer-value itimer)))
714 (min next-wakeup (itimer-value itimer))))
715 (and (itimer-is-idle itimer)
716 (set-itimer-recorded-run-time itimer (current-time)))
717 ;; itimer has expired, we must call its function.
718 ;; protect our local vars from the itimer function.
719 ;; allow keyboard quit to occur, but catch and report it.
720 ;; provide the variable `current-itimer' in case the function
723 (condition-case condition-data
725 ;; Suppress warnings - see comment below.
726 (defvar last-event-time)
730 (defvar time-elapsed)
731 (let* ((current-itimer itimer)
734 ;; for FSF Emacs timer.el emulation under XEmacs.
735 ;; eldoc expect this to be done, apparently.
737 ;; bind these variables so that the itimer
738 ;; function can't screw with them.
739 last-event-time next-wakeup
740 itimer itimers time-elapsed)
741 (if (itimer-uses-arguments current-itimer)
742 (apply (itimer-function current-itimer)
743 (itimer-function-arguments current-itimer))
744 (funcall (itimer-function current-itimer)))))
745 (error (message "itimer \"%s\" signaled: %s" (itimer-name itimer)
746 (prin1-to-string condition-data)))
747 (quit (message "itimer \"%s\" quit" (itimer-name itimer))))
748 ;; restart the itimer if we should, otherwise delete it.
749 (if (null (itimer-restart itimer))
750 (delete-itimer itimer)
751 (set-itimer-value-internal itimer (itimer-restart itimer))
752 (setq next-wakeup (min next-wakeup (itimer-value itimer))))))
753 (setq itimers (cdr itimers)))
754 ;; make another sweep through the list to catch any timers
755 ;; that might have been added by timer functions above.
756 (setq itimers itimer-list)
758 (setq next-wakeup (min next-wakeup (itimer-value (car itimers)))
759 itimers (cdr itimers)))
760 ;; if user is viewing the timer list, update displayed info.
761 (let ((b (get-buffer "*Itimer List*")))
762 (if (and b (get-buffer-window b))
767 (defun itimer-process-filter (process string)
768 ;; If the itimer process dies and generates output while doing
769 ;; so, we may be called before the process-sentinel. Sanity
770 ;; check the output just in case...
771 (if (not (string-match "^[0-9]" string))
772 (progn (message "itimer process gave odd output: %s" string)
773 ;; it may be still alive and waiting for input
774 (process-send-string itimer-process "3\n"))
775 ;; if there are no active itimers, return quickly.
779 (setq wakeup (itimer-run-expired-timers (string-to-int string)))
780 (and (null wakeup) (process-send-string process "1\n")))
781 (setq itimer-next-wakeup wakeup))
782 (setq itimer-next-wakeup 600))
783 ;; tell itimer-process when to wakeup again
784 (process-send-string itimer-process
785 (concat (int-to-string itimer-next-wakeup)
788 (defun itimer-process-sentinel (process message)
789 (let ((inhibit-quit t))
790 (if (eq (process-status process) 'stop)
791 (continue-process process)
792 ;; not stopped, so it must have died.
794 (delete-process process)
795 (setq itimer-process nil)
796 ;; now, if there are any active itimers then we need to immediately
797 ;; start another itimer process, otherwise we can wait until the next
798 ;; start-itimer call, which will start one automatically.
799 (if (null itimer-list)
801 ;; there may have been an error message in the echo area;
802 ;; give the user at least a little time to read it.
804 (message "itimer process %s... respawning." (substring message 0 -1))
805 (itimer-process-start)))))
807 (defun itimer-process-start ()
808 (let ((inhibit-quit t)
809 (process-connection-type nil))
810 (setq itimer-process (start-process "itimer" nil "itimer"))
811 (process-kill-without-query itimer-process)
812 (set-process-filter itimer-process 'itimer-process-filter)
813 (set-process-sentinel itimer-process 'itimer-process-sentinel)
814 ;; Tell itimer process to wake up quickly, so that a correct
815 ;; wakeup time can be computed. Zero loses because of
816 ;; underlying itimer implementations that use 0 to mean
817 ;; `disable the itimer'.
818 (setq itimer-next-wakeup itimer-short-interval)
819 (process-send-string itimer-process
820 (format "%s\n" itimer-next-wakeup))))
822 (defun itimer-process-wakeup ()
823 (interrupt-process itimer-process)
824 (accept-process-output))
826 (defun itimer-timer-start ()
827 (let ((inhibit-quit t))
828 (setq itimer-next-wakeup itimer-short-interval
829 itimer-timer-last-wakeup (current-time)
830 itimer-timer (add-timeout itimer-short-interval
831 'itimer-timer-driver nil nil))))
833 (defun itimer-disable-timeout (timeout)
834 ;; Disgusting hack, but necessary because there is no other way
835 ;; to remove a timer that has a restart value from while that
836 ;; timer's function is being run. (FSF Emacs only.)
837 (if (vectorp timeout)
838 (aset timeout 4 nil))
839 (disable-timeout timeout))
841 (defun itimer-timer-wakeup ()
842 (let ((inhibit-quit t))
843 (itimer-disable-timeout itimer-timer)
844 (setq itimer-timer (add-timeout itimer-short-interval
845 'itimer-timer-driver nil 5))))
847 (defun itimer-time-difference (t1 t2)
848 (let (usecs secs 65536-secs carry)
849 (setq usecs (- (nth 2 t1) (nth 2 t2)))
852 usecs (+ usecs 1000000))
854 (setq secs (- (nth 1 t1) (nth 1 t2) carry))
859 (setq 65536-secs (- (nth 0 t1) (nth 0 t2) carry))
860 (+ (* 65536-secs 65536.0)
862 (/ usecs 1000000.0))))
864 (defun itimer-timer-driver (&rest ignored)
865 ;; inhibit quit because if the user quits at an inopportune
866 ;; time, the timer process won't be launched again and the
867 ;; system stops working. itimer-run-expired-timers allows
868 ;; individual timer function to be aborted, so the user can
869 ;; escape a feral timer function.
870 (if (not itimer-inside-driver)
871 (let* ((inhibit-quit t)
872 (itimer-inside-driver t)
874 (elapsed (itimer-time-difference now itimer-timer-last-wakeup))
876 (setq itimer-timer-last-wakeup now
877 sleep (itimer-run-expired-timers elapsed))
878 (itimer-disable-timeout itimer-timer)
879 (setq itimer-next-wakeup sleep
880 itimer-timer (add-timeout sleep 'itimer-timer-driver nil 5)))))
882 (defun itimer-driver-start ()
883 (if (fboundp 'add-timeout)
885 (itimer-process-start)))
887 (defun itimer-driver-wakeup ()
888 (if (fboundp 'add-timeout)
889 (itimer-timer-wakeup)
890 (itimer-process-wakeup)))