Convert more defvars to defcustoms.

[bpt/emacs.git] / lisp / emacs-lisp / timer.el

diff --git a/lisp/emacs-lisp/timer.el b/lisp/emacs-lisp/timer.el
index 27fd79a..11ec0f0 100644 (file)
--- a/lisp/emacs-lisp/timer.el
+++ b/lisp/emacs-lisp/timer.el
@@ -1,6 +1,6 @@
 ;;; timer.el --- run a function with args at some time in future
 
-;; Copyright (C) 1996, 2001-2011  Free Software Foundation, Inc.
+;; Copyright (C) 1996, 2001-2012  Free Software Foundation, Inc.
 
 ;; Maintainer: FSF
 ;; Package: emacs
@@ -119,14 +119,7 @@ SECS may be either an integer or a floating point number."
 
 (defun timer--time-less-p (t1 t2)
   "Say whether time value T1 is less than time value T2."
-  ;; FIXME just use time-less-p.
-  (destructuring-bind (high1 low1 micro1) (timer--time t1)
-    (destructuring-bind (high2 low2 micro2) (timer--time t2)
-      (or (< high1 high2)
-          (and (= high1 high2)
-               (or (< low1 low2)
-                   (and (= low1 low2)
-                        (< micro1 micro2))))))))
+  (time-less-p (timer--time t1) (timer--time t2)))
 
 (defun timer-inc-time (timer secs &optional usecs)
   "Increment the time set in TIMER by SECS seconds and USECS microseconds.
@@ -247,21 +240,20 @@ and idle timers such as are scheduled by `run-with-idle-timer'."
 (defvar timer-event-last-2 nil
   "Third-to-last timer that was run.")
 
-(defvar timer-max-repeats 10
-  "*Maximum number of times to repeat a timer, if many repeats are delayed.
+(defcustom timer-max-repeats 10
+  "Maximum number of times to repeat a timer, if many repeats are delayed.
 Timer invocations can be delayed because Emacs is suspended or busy,
 or because the system's time changes.  If such an occurrence makes it
 appear that many invocations are overdue, this variable controls
-how many will really happen.")
+how many will really happen."
+  :type 'integer
+  :group 'internal)
 
 (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."
-  ;; FIXME: (float-time (time-subtract (timer--time timer) time))
-  (let ((high (- (car time) (timer--high-seconds timer)))
-       (low (- (nth 1 time) (timer--low-seconds timer))))
-    (+ low (* high 65536))))
+  (float-time (time-subtract time (timer--time timer))))
 
 (defun timer-event-handler (timer)
   "Call the handler for the timer TIMER.
@@ -412,10 +404,6 @@ This function returns a timer object which you can use in `cancel-timer'."
     (timer-activate-when-idle timer t)
     timer))
 \f
-(defun with-timeout-handler (tag)
-  "This is the timer function used for the timer made by `with-timeout'."
-  (throw tag 'timeout))
-
 (defvar with-timeout-timers nil
   "List of all timers used by currently pending `with-timeout' calls.")
 
@@ -427,24 +415,27 @@ event (such as keyboard input, input from subprocesses, or a certain time);
 if the program loops without waiting in any way, the timeout will not
 be detected.
 \n(fn (SECONDS TIMEOUT-FORMS...) BODY)"
-  (declare (indent 1))
+  (declare (indent 1) (debug ((form body) body)))
   (let ((seconds (car list))
-       (timeout-forms (cdr list)))
-    `(let ((with-timeout-tag (cons nil nil))
-          with-timeout-value with-timeout-timer
-          (with-timeout-timers with-timeout-timers))
-       (if (catch with-timeout-tag
-            (progn
-              (setq with-timeout-timer
-                    (run-with-timer ,seconds nil
-                                     'with-timeout-handler
-                                     with-timeout-tag))
-              (push with-timeout-timer with-timeout-timers)
-              (setq with-timeout-value (progn . ,body))
-              nil))
-          (progn . ,timeout-forms)
-        (cancel-timer with-timeout-timer)
-        with-timeout-value))))
+       (timeout-forms (cdr list))
+        (timeout (make-symbol "timeout")))
+    `(let ((-with-timeout-value-
+            (catch ',timeout
+              (let* ((-with-timeout-timer-
+                      (run-with-timer ,seconds nil
+                                      (lambda () (throw ',timeout ',timeout))))
+                     (with-timeout-timers
+                         (cons -with-timeout-timer- with-timeout-timers)))
+                (unwind-protect
+                    ,@body
+                  (cancel-timer -with-timeout-timer-))))))
+       ;; It is tempting to avoid the `if' altogether and instead run
+       ;; timeout-forms in the timer, just before throwing `timeout'.
+       ;; But that would mean that timeout-forms are run in the deeper
+       ;; dynamic context of the timer, with inhibit-quit set etc...
+       (if (eq -with-timeout-value- ',timeout)
+           (progn ,@timeout-forms)
+         -with-timeout-value-))))
 
 (defun with-timeout-suspend ()
   "Stop the clock for `with-timeout'.  Used by debuggers.