Stop cursor blink after blink-cursor-blinks (10), stop timers when not blinking.

[bpt/emacs.git] / lisp / frame.el

diff --git a/lisp/frame.el b/lisp/frame.el
index 3ac24a5..a37d118 100644 (file)
--- a/lisp/frame.el
+++ b/lisp/frame.el
@@ -1671,6 +1671,16 @@ left untouched.  FRAME nil or omitted means use the selected frame."
   :type 'number
   :group 'cursor)
 
+(defcustom blink-cursor-blinks 10
+  "How many times to blink before using a solid cursor on NS and X.
+Use 0 or negative value to blink forever."
+  :version "24.4"
+  :type 'integer
+  :group 'cursor)
+
+(defvar blink-cursor-blinks-done 1
+  "Number of blinks done since we started blinking on NS and X")
+
 (defvar blink-cursor-idle-timer nil
   "Timer started after `blink-cursor-delay' seconds of Emacs idle time.
 The function `blink-cursor-start' is called when the timer fires.")
@@ -1688,6 +1698,7 @@ command starts, by installing a pre-command hook."
   (when (null blink-cursor-timer)
     ;; Set up the timer first, so that if this signals an error,
     ;; blink-cursor-end is not added to pre-command-hook.
+    (setq blink-cursor-blinks-done 1)
     (setq blink-cursor-timer
          (run-with-timer blink-cursor-interval blink-cursor-interval
                          'blink-cursor-timer-function))
@@ -1696,7 +1707,15 @@ command starts, by installing a pre-command hook."
 
 (defun blink-cursor-timer-function ()
   "Timer function of timer `blink-cursor-timer'."
-  (internal-show-cursor nil (not (internal-show-cursor-p))))
+  (internal-show-cursor nil (not (internal-show-cursor-p)))
+  ;; Each blink is two calls to this function.
+  (when (memq window-system '(x ns))
+    (setq blink-cursor-blinks-done (1+ blink-cursor-blinks-done))
+    (when (and (> blink-cursor-blinks 0)
+              (<= (* 2 blink-cursor-blinks) blink-cursor-blinks-done))
+      (blink-cursor-suspend)
+      (add-hook 'post-command-hook 'blink-cursor-check))))
+
 
 (defun blink-cursor-end ()
   "Stop cursor blinking.
@@ -1709,6 +1728,29 @@ itself as a pre-command hook."
     (cancel-timer blink-cursor-timer)
     (setq blink-cursor-timer nil)))
 
+(defun blink-cursor-suspend ()
+  "Suspend cursor blinking on NS and X.
+This is called when no frame has focus and timers can be suspended.
+Timers are restarted by `blink-cursor-check', which is called when a
+frame receives focus."
+  (when (memq window-system '(x ns))
+    (blink-cursor-end)
+    (when blink-cursor-idle-timer
+      (cancel-timer blink-cursor-idle-timer)
+      (setq blink-cursor-idle-timer nil))))
+
+(defun blink-cursor-check ()
+  "Check if cursot blinking shall be restarted.
+This is done when a frame gets focus.  Blink timers may be stopped by
+`blink-cursor-suspend'."
+  (when (and blink-cursor-mode
+            (not blink-cursor-idle-timer))
+    (remove-hook 'post-command-hook 'blink-cursor-check)
+    (setq blink-cursor-idle-timer
+          (run-with-idle-timer blink-cursor-delay
+                               blink-cursor-delay
+                               'blink-cursor-start))))
+
 (define-obsolete-variable-alias 'blink-cursor 'blink-cursor-mode "22.1")
 
 (define-minor-mode blink-cursor-mode