* emacs-lisp/timer.el (timer-set-idle-time, run-with-idle-timer):

	Accept internal time format for SECS arg.
	(timer-relative-time): Doc fix.

	* jit-lock.el: "Stealth fontification by requeuing timers" patch,
	adapted from Martin Rudalics.
	(jit-lock-stealth-repeat-timer, jit-lock-stealth-buffers): New vars.
	(jit-lock-mode): Create jit-lock-stealth-repeat-timer.
	(jit-lock-stealth-fontify): Reschedule as a idle timer instead of
	using sit-for.

3 files changed, 84 insertions, 67 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 72a1bed4397..554274a2544 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,16 @@
+2006-08-24  Chong Yidong  <cyd@stupidchicken.com>
+
+        * emacs-lisp/timer.el (timer-set-idle-time, run-with-idle-timer):
+        Accept internal time format for SECS arg.
+        (timer-relative-time): Doc fix.
+
+        * jit-lock.el: "Stealth fontification by requeuing timers" patch,
+        adapted from Martin Rudalics.
+        (jit-lock-stealth-repeat-timer, jit-lock-stealth-buffers): New vars.
+        (jit-lock-mode): Create jit-lock-stealth-repeat-timer.
+        (jit-lock-stealth-fontify): Reschedule as a idle timer instead of
+        using sit-for.
+
 2006-08-24  Francesc Rocher  <francesc.rocher@gmail.com>
 
         * cus-start.el (all): Add `overline-margin' and
diff --git a/lisp/emacs-lisp/timer.el b/lisp/emacs-lisp/timer.el
index ed85bc765f7..82eac50c874 100644
--- a/lisp/emacs-lisp/timer.el
+++ b/lisp/emacs-lisp/timer.el
@@ -60,14 +60,22 @@ fire repeatedly that many seconds apart."
 
 (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-idle-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"))
-  (aset timer 1 0)
-  (aset timer 2 0)
-  (aset timer 3 0)
-  (timer-inc-time timer secs)
+  (if (consp secs)
+      (progn (aset timer 1 (car secs))
+             (aset timer 2 (if (consp (cdr secs)) (car (cdr secs)) (cdr secs)))
+             (aset timer 3 (or (and (consp (cdr secs)) (consp (cdr (cdr secs)))
+                                    (nth 2 secs))
+                               0)))
+    (aset timer 1 0)
+    (aset timer 2 0)
+    (aset timer 3 0)
+    (timer-inc-time timer secs))
   (aset timer 4 repeat)
   timer)
 
@@ -104,7 +112,7 @@ of SECS seconds since the epoch.  SECS may be a fraction."
 
 (defun timer-relative-time (time secs &optional usecs)
   "Advance TIME by SECS seconds and optionally USECS microseconds.
-SECS may be a fraction."
+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))))
@@ -412,7 +420,8 @@ This function is for compatibility; see also `run-with-timer'."
 (defun run-with-idle-timer (secs repeat function &rest args)
   "Perform an action the next time Emacs is idle for SECS seconds.
 The action is to call FUNCTION with arguments ARGS.
-SECS may be an integer or a floating point number.
+SECS may be an integer, a floating point number, or the internal
+time format (HIGH LOW USECS) returned by, e.g., `current-idle-time'.
 If Emacs is currently idle, and has been idle for N seconds (N < SECS),
 then it will call FUNCTION in SECS - N seconds from now.
 
diff --git a/lisp/jit-lock.el b/lisp/jit-lock.el
index 606cd1e0b84..89959ad8525 100644
--- a/lisp/jit-lock.el
+++ b/lisp/jit-lock.el
@@ -171,6 +171,8 @@ If nil, contextual fontification is disabled.")
 
 (defvar jit-lock-stealth-timer nil
   "Timer for stealth fontification in Just-in-time Lock mode.")
+(defvar jit-lock-stealth-repeat-timer nil
+  "Timer for repeated stealth fontification in Just-in-time Lock mode.")
 (defvar jit-lock-context-timer nil
   "Timer for context fontification in Just-in-time Lock mode.")
 (defvar jit-lock-defer-timer nil
@@ -178,6 +180,8 @@ If nil, contextual fontification is disabled.")
 
 (defvar jit-lock-defer-buffers nil
   "List of buffers with pending deferred fontification.")
+(defvar jit-lock-stealth-buffers nil
+  "List of buffers that are being fontified stealthily.")
 
 ;;; JIT lock mode
 
@@ -225,6 +229,13 @@ the variable `jit-lock-stealth-nice'."
                  (run-with-idle-timer jit-lock-stealth-time t
                                       'jit-lock-stealth-fontify)))
 
+         ;; Create, but do not activate, the idle timer for repeated
+         ;; stealth fontification.
+         (when (and jit-lock-stealth-time (null jit-lock-stealth-repeat-timer))
+           (setq jit-lock-stealth-repeat-timer (timer-create))
+           (timer-set-function jit-lock-stealth-repeat-timer
+                               'jit-lock-stealth-fontify '(t)))
+
          ;; Init deferred fontification timer.
          (when (and jit-lock-defer-time (null jit-lock-defer-timer))
            (setq jit-lock-defer-timer
@@ -443,71 +454,55 @@ Value is nil if there is nothing more to fontify."
                            (t next))))
         result))))
 
-
-(defun jit-lock-stealth-fontify ()
+(defun jit-lock-stealth-fontify (&optional repeat)
   "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
+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."
+  ;; Cancel timer for repeated invocations.
+  (unless repeat
+    (cancel-timer jit-lock-stealth-repeat-timer))
   (unless (or executing-kbd-macro
               memory-full
-              (window-minibuffer-p (selected-window)))
-    (let ((buffers (buffer-list))
-          (outer-buffer (current-buffer))
+              (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)))))
+    (let ((buffer (car jit-lock-stealth-buffers))
+          (delay 0)
           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))))))))))))))
-
+          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
+        (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)))))
 
 
 ;;; Deferred fontification.