Re: jit-lock timer etc.

[Chong Yidong]

martin rudalics <address@hidden> writes:

>> I think this ought to use run-with-idle-timer
>> and current-idle-time, as in my patch.
>
> I was not able to accomplish that since the idle timer does not trigger.
> In analogy to your patch I replaced the above by
>
>       (when (and jit-lock-stealth-buffers jit-lock-stealth-time)
>       ;; Call us again.
>       (timer-set-idle-time jit-lock-stealth-repeat-timer (current-idle-time))
>       (timer-inc-time jit-lock-stealth-repeat-timer delay)
>       (timer-activate-when-idle jit-lock-stealth-repeat-timer t)

I don't know what was wrong with this code since you didn't post it.
It looks like you simply forgot to initialize jit-lock-stealth-repeat-timer,
but I can't be sure.  However, the following patch, based on the last
patch you posted to this list with minimal modifications, works fine
for me.

It applies to the current CVS tree, and uses `current-idle-time'.  It
includes and uses the change to `timer-set-idle-time' which I
previously posted, allowing it to accept the value returned by
`current-idle-time'.

I have verified that the idle timer triggers correctly, stops
correctly when user input comes in, and resumes when Emacs becomes
idle again.


*** emacs/lisp/jit-lock.el.~1.54.~      2006-08-17 11:49:36.000000000 -0400
--- emacs/lisp/jit-lock.el      2006-08-24 11:21:23.000000000 -0400
***************
*** 443,513 ****
                           (t next))))
        result))))
  
  
! (defun jit-lock-stealth-fontify ()
    "Fontify buffers stealthily.
! This functions is called after Emacs has been idle for
! `jit-lock-stealth-time' seconds."
!   ;; I used to check `inhibit-read-only' here, but I can't remember why.  
-stef
    (unless (or executing-kbd-macro
              memory-full
!             (window-minibuffer-p (selected-window)))
!     (let ((buffers (buffer-list))
!         (outer-buffer (current-buffer))
          minibuffer-auto-raise
!         message-log-max)
!       (with-local-quit
!       (while (and buffers (not (input-pending-p)))
!         (with-current-buffer (pop buffers)
!           (when jit-lock-mode
!             ;; This is funny.  Calling sit-for with 3rd arg non-nil
!             ;; so that it doesn't redisplay, internally calls
!             ;; wait_reading_process_input also with a parameter
!             ;; saying "don't redisplay."  Since this function here
!             ;; is called periodically, this effectively leads to
!             ;; process output not being redisplayed at all because
!             ;; redisplay_internal is never called.  (That didn't
!             ;; work in the old redisplay either.)  So, we learn that
!             ;; we mustn't call sit-for that way here.  But then, we
!             ;; have to be cautious not to call sit-for in a widened
!             ;; buffer, since this could display hidden parts of that
!             ;; buffer.  This explains the seemingly weird use of
!             ;; save-restriction/widen here.
! 
!             (with-temp-message (if jit-lock-stealth-verbose
!                                    (concat "JIT stealth lock "
!                                            (buffer-name)))
! 
!               ;; In the following code, the `sit-for' calls cause a
!               ;; redisplay, so it's required that the
!               ;; buffer-modified flag of a buffer that is displayed
!               ;; has the right value---otherwise the mode line of
!               ;; an unmodified buffer would show a `*'.
!               (let (start
!                     (nice (or jit-lock-stealth-nice 0))
!                     (point (point-min)))
!                 (while (and (setq start
!                                   (jit-lock-stealth-chunk-start point))
!                             ;; In case sit-for runs any timers,
!                             ;; give them the expected current buffer.
!                             (with-current-buffer outer-buffer
!                               (sit-for nice)))
! 
!                   ;; fontify a block.
!                   (jit-lock-fontify-now start (+ start jit-lock-chunk-size))
!                   ;; If stealth jit-locking is done backwards, this leads to
!                   ;; excessive O(n^2) refontification.   -stef
!                   ;; (when (>= jit-lock-context-unfontify-pos start)
!                   ;;   (setq jit-lock-context-unfontify-pos end))
! 
!                   ;; Wait a little if load is too high.
!                   (when (and jit-lock-stealth-load
!                              (> (car (load-average)) jit-lock-stealth-load))
!                     ;; In case sit-for runs any timers,
!                     ;; give them the expected current buffer.
!                     (with-current-buffer outer-buffer
!                       (sit-for (or jit-lock-stealth-time 30))))))))))))))
! 
  
  
  ;;; Deferred fontification.
--- 443,511 ----
                           (t next))))
        result))))
  
+ (defvar jit-lock-stealth-buffers nil
+   "List of buffers that should be fontified stealthily.")
  
! (defvar jit-lock-stealth-repeat-timer nil
!   "Timer for repeated stealth fontification.")
! 
! (defun jit-lock-stealth-fontify (&optional repeat)
    "Fontify buffers stealthily.
! This function is called repeatedly after Emacs has become idle for
! `jit-lock-stealth-time' seconds.  Optional argument REPEAT is expected
! non-nil in a repeated invocation of this function."
    (unless (or executing-kbd-macro
              memory-full
!             (window-minibuffer-p (selected-window))
!             ;; For first invocation set up `jit-lock-stealth-buffers'.
!             ;; In repeated invocations it's already been set up.
!             (null (if repeat
!                       jit-lock-stealth-buffers
!                     (setq jit-lock-stealth-buffers (buffer-list)))))
!     ;; Cancel timer for repeated invocations.
!     (when (timerp jit-lock-stealth-repeat-timer)
!       (cancel-timer jit-lock-stealth-repeat-timer))
!     (let ((buffer (car jit-lock-stealth-buffers))
!         (delay 0)
          minibuffer-auto-raise
!         message-log-max
!         start)
!       (if (and jit-lock-stealth-load
!              (> (car (load-average)) jit-lock-stealth-load))
!         ;; Wait a little if load is too high.
!         (setq delay jit-lock-stealth-time)
!       (if (buffer-live-p buffer)
!           (with-current-buffer buffer
!             (if (and jit-lock-mode
!                      (setq start (jit-lock-stealth-chunk-start (point))))
!                 ;; Fontify one block of at most `jit-lock-chunk-size'
!                 ;; characters.
!                 (with-temp-message (if jit-lock-stealth-verbose
!                                        (concat "JIT stealth lock "
!                                                (buffer-name)))
!                   (jit-lock-fontify-now start
!                                         (+ start jit-lock-chunk-size))
!                   ;; Run again after `jit-lock-stealth-nice' seconds.
!                   (setq delay (or jit-lock-stealth-nice 0)))
!               ;; Nothing to fontify here.  Remove this buffer from
!               ;; `jit-lock-stealth-buffers' and run again immediately.
!               (setq jit-lock-stealth-buffers
!                     (cdr jit-lock-stealth-buffers))))
!         ;; Buffer is no longer live.  Remove it from
!         ;; `jit-lock-stealth-buffers' and run again immediately.
!         (setq jit-lock-stealth-buffers
!               (cdr jit-lock-stealth-buffers))))
!       ;; Call us again.
!       (when jit-lock-stealth-buffers
!       (if repeat
!           (progn (timer-set-idle-time
!                   jit-lock-stealth-repeat-timer (current-idle-time))
!                  (timer-inc-time jit-lock-stealth-repeat-timer delay)
!                  (timer-activate-when-idle
!                   jit-lock-stealth-repeat-timer t))
!         (setq jit-lock-stealth-repeat-timer
!               (run-at-time delay
!                            nil 'jit-lock-stealth-fontify t)))))))
  
  
  ;;; Deferred fontification.
*** emacs/lisp/emacs-lisp/timer.el.~1.12.~      2006-08-20 09:55:37.000000000 
-0400
--- emacs/lisp/emacs-lisp/timer.el      2006-08-24 10:45:48.000000000 -0400
***************
*** 60,73 ****
  
  (defun timer-set-idle-time (timer secs &optional repeat)
    "Set the trigger idle time of TIMER to SECS.
  If optional third argument REPEAT is non-nil, make the timer
  fire each time Emacs is idle for that many seconds."
    (or (timerp timer)
        (error "Invalid timer"))
!   (aset timer 1 0)
!   (aset timer 2 0)
!   (aset timer 3 0)
!   (timer-inc-time timer secs)
    (aset timer 4 repeat)
    timer)
  
--- 60,81 ----
  
  (defun timer-set-idle-time (timer secs &optional repeat)
    "Set the trigger idle time of TIMER to SECS.
+ SECS may be an integer, floating point number, or the internal
+ time format (HIGH LOW USECS) returned by, e.g., `current-time'.
  If optional third argument REPEAT is non-nil, make the timer
  fire each time Emacs is idle for that many seconds."
    (or (timerp timer)
        (error "Invalid timer"))
!   (if (consp secs)
!       (progn (aset timer 1 (car secs))
!            (aset timer 2 (if (consp (cdr time)) (car (cdr time)) (cdr time)))
!            (aset timer 3 (or (and (consp (cdr time)) (consp (cdr (cdr time)))
!                                   (nth 2 time))
!                              0)))
!     (aset timer 1 0)
!     (aset timer 2 0)
!     (aset timer 3 0)
!     (timer-inc-time timer secs))
    (aset timer 4 repeat)
    timer)
  
***************
*** 104,110 ****
  
  (defun timer-relative-time (time secs &optional usecs)
    "Advance TIME by SECS seconds and optionally USECS microseconds.
! SECS may be a fraction."
    (let ((high (car time))
        (low (if (consp (cdr time)) (nth 1 time) (cdr time)))
        (micro (if (numberp (car-safe (cdr-safe (cdr time))))
--- 112,118 ----
  
  (defun timer-relative-time (time secs &optional usecs)
    "Advance TIME by SECS seconds and optionally USECS microseconds.
! SECS may be either an integer or a floating point number."
    (let ((high (car time))
        (low (if (consp (cdr time)) (nth 1 time) (cdr time)))
        (micro (if (numberp (car-safe (cdr-safe (cdr time))))