;;; autorevert.el --- revert buffers when files on disk change
-;; Copyright (C) 1997-1999, 2001-2013 Free Software Foundation, Inc.
+;; Copyright (C) 1997-1999, 2001-2015 Free Software Foundation, Inc.
;; Author: Anders Lindgren <andersl@andersl.com>
;; Keywords: convenience
(delq (current-buffer) auto-revert-buffer-list)))
(auto-revert-set-timer)
(when auto-revert-mode
- (let (auto-revert-use-notify)
- (auto-revert-buffers)
- (setq auto-revert-tail-mode nil))))
+ (auto-revert-buffers)
+ (setq auto-revert-tail-mode nil)))
;;;###autoload
(y-or-n-p "File changed on disk, content may be missing. \
Perform a full revert? ")
;; Use this (not just revert-buffer) for point-preservation.
- (let (auto-revert-use-notify)
- (auto-revert-handler)))
+ (auto-revert-buffers))
;; else we might reappend our own end when we save
(add-hook 'before-save-hook (lambda () (auto-revert-tail-mode 0)) nil t)
(or (local-variable-p 'auto-revert-tail-pos) ; don't lose prior position
:global t :group 'auto-revert :lighter global-auto-revert-mode-text
(auto-revert-set-timer)
(if global-auto-revert-mode
- (let (auto-revert-use-notify)
- (auto-revert-buffers))
+ (auto-revert-buffers)
(dolist (buf (buffer-list))
(with-current-buffer buf
(when auto-revert-use-notify
(defun auto-revert-notify-add-watch ()
"Enable file notification for current buffer's associated file."
- (when (string-match auto-revert-notify-exclude-dir-regexp
- (expand-file-name default-directory))
- ;; Fallback to file checks.
- (set (make-local-variable 'auto-revert-use-notify) nil))
-
- (when (and buffer-file-name auto-revert-use-notify
- (not auto-revert-notify-watch-descriptor))
- (setq auto-revert-notify-watch-descriptor
- (ignore-errors
- (file-notify-add-watch
- (expand-file-name buffer-file-name default-directory)
- '(change attribute-change) 'auto-revert-notify-handler)))
- (if auto-revert-notify-watch-descriptor
- (progn
- (puthash
- auto-revert-notify-watch-descriptor
- (cons (current-buffer)
- (gethash auto-revert-notify-watch-descriptor
- auto-revert-notify-watch-descriptor-hash-list))
- auto-revert-notify-watch-descriptor-hash-list)
- (add-hook (make-local-variable 'kill-buffer-hook)
- 'auto-revert-notify-rm-watch))
+ ;; We can assume that `buffer-file-name' and
+ ;; `auto-revert-use-notify' are non-nil.
+ (if (or (string-match auto-revert-notify-exclude-dir-regexp
+ (expand-file-name default-directory))
+ (file-symlink-p (or buffer-file-name default-directory)))
+
;; Fallback to file checks.
- (set (make-local-variable 'auto-revert-use-notify) nil))))
+ (set (make-local-variable 'auto-revert-use-notify) nil)
+
+ (when (not auto-revert-notify-watch-descriptor)
+ (setq auto-revert-notify-watch-descriptor
+ (ignore-errors
+ (if buffer-file-name
+ (file-notify-add-watch
+ (expand-file-name buffer-file-name default-directory)
+ '(change attribute-change)
+ 'auto-revert-notify-handler)
+ (file-notify-add-watch
+ (expand-file-name default-directory)
+ '(change)
+ 'auto-revert-notify-handler))))
+ (if auto-revert-notify-watch-descriptor
+ (progn
+ (puthash
+ auto-revert-notify-watch-descriptor
+ (cons (current-buffer)
+ (gethash auto-revert-notify-watch-descriptor
+ auto-revert-notify-watch-descriptor-hash-list))
+ auto-revert-notify-watch-descriptor-hash-list)
+ (add-hook (make-local-variable 'kill-buffer-hook)
+ 'auto-revert-notify-rm-watch))
+ ;; Fallback to file checks.
+ (set (make-local-variable 'auto-revert-use-notify) nil)))))
+
+;; If we have file notifications, we want to update the auto-revert buffers
+;; immediately when a notification occurs. Since file updates can happen very
+;; often, we want to skip some revert operations so that we don't spend all our
+;; time reverting the buffer.
+;;
+;; We do this by reverting immediately in response to the first in a flurry of
+;; notifications. We suppress subsequent notifications until the next time
+;; `auto-revert-buffers' is called (this happens on a timer with a period set by
+;; `auto-revert-interval').
+(defvar auto-revert-buffers-counter 1
+ "Incremented each time `auto-revert-buffers' is called")
+(defvar-local auto-revert-buffers-counter-lockedout 0
+ "Buffer-local value to indicate whether we should immediately
+update the buffer on a notification event or not. If
+
+ (= auto-revert-buffers-counter-lockedout
+ auto-revert-buffers-counter)
+
+then the updates are locked out, and we wait until the next call
+of `auto-revert-buffers' to revert the buffer. If no lockout is
+present, then we revert immediately and set the lockout, so that
+no more reverts are possible until the next call of
+`auto-revert-buffers'")
(defun auto-revert-notify-handler (event)
"Handle an EVENT returned from file notification."
- (ignore-errors
+ (with-demoted-errors
(let* ((descriptor (car event))
(action (nth 1 event))
(file (nth 2 event))
auto-revert-notify-watch-descriptor-hash-list)))
;; Check, that event is meant for us.
(cl-assert descriptor)
- ;; We do not handle `deleted', because nothing has to be refreshed.
- (cl-assert (memq action '(attribute-changed changed created renamed)) t)
;; Since we watch a directory, a file name must be returned.
(cl-assert (stringp file))
(when (eq action 'renamed) (cl-assert (stringp file1)))
;; Loop over all buffers, in order to find the intended one.
- (dolist (buffer buffers)
+ (cl-dolist (buffer buffers)
(when (buffer-live-p buffer)
(with-current-buffer buffer
- (when (and (stringp buffer-file-name)
- (or
- (and (memq action '(attribute-changed changed created))
- (string-equal
- (file-name-nondirectory file)
- (file-name-nondirectory buffer-file-name)))
- (and (eq action 'renamed)
- (string-equal
- (file-name-nondirectory file1)
- (file-name-nondirectory buffer-file-name)))))
+ (when (or
+ ;; A buffer associated with a file.
+ (and (stringp buffer-file-name)
+ (or
+ (and (memq action '(attribute-changed changed created))
+ (string-equal
+ (file-name-nondirectory file)
+ (file-name-nondirectory buffer-file-name)))
+ (and (eq action 'renamed)
+ (string-equal
+ (file-name-nondirectory file1)
+ (file-name-nondirectory buffer-file-name)))))
+ ;; A buffer w/o a file, like dired.
+ (and (null buffer-file-name)
+ (memq action '(created renamed deleted))))
;; Mark buffer modified.
(setq auto-revert-notify-modified-p t)
+
+ ;; Revert the buffer now if we're not locked out.
+ (when (/= auto-revert-buffers-counter-lockedout
+ auto-revert-buffers-counter)
+ (auto-revert-handler)
+ (setq auto-revert-buffers-counter-lockedout
+ auto-revert-buffers-counter))
+
;; No need to check other buffers.
(cl-return))))))))
;; the values.
(remote-file-name-inhibit-cache t)
(revert
- (or (and buffer-file-name
- (or auto-revert-remote-files
+ (if buffer-file-name
+ (and (or auto-revert-remote-files
(not (file-remote-p buffer-file-name)))
(or (not auto-revert-use-notify)
auto-revert-notify-modified-p)
(funcall (or buffer-stale-function
#'buffer-stale--default-function)
t)))
- (and (or auto-revert-mode
- global-auto-revert-non-file-buffers)
- (funcall (or buffer-stale-function
- #'buffer-stale--default-function)
- t))))
+ (and (or auto-revert-mode
+ global-auto-revert-non-file-buffers)
+ (funcall (or buffer-stale-function
+ #'buffer-stale--default-function)
+ t))))
eob eoblist)
(setq auto-revert-notify-modified-p nil)
(when revert
are checked.
Non-file buffers that have a custom `revert-buffer-function' and
-a `buffer-stale-function' are reverted either when Auto-Revert
+`buffer-stale-function' are reverted either when Auto-Revert
Mode is active in that buffer, or when the variable
`global-auto-revert-non-file-buffers' is non-nil and Global
Auto-Revert Mode is active.
This function is also responsible for removing buffers no longer in
Auto-Revert mode from `auto-revert-buffer-list', and for canceling
the timer when no buffers need to be checked."
+
+ (setq auto-revert-buffers-counter
+ (1+ auto-revert-buffers-counter))
+
(save-match-data
(let ((bufs (if global-auto-revert-mode
(buffer-list)
auto-revert-buffer-list))
- (remaining ())
- (new ()))
+ remaining new)
;; Partition `bufs' into two halves depending on whether or not
;; the buffers are in `auto-revert-remaining-buffers'. The two
;; halves are then re-joined with the "remaining" buffers at the
(delq buf auto-revert-buffer-list)))
(when (auto-revert-active-p)
;; Enable file notification.
- (when (and auto-revert-use-notify buffer-file-name
+ (when (and auto-revert-use-notify
(not auto-revert-notify-watch-descriptor))
(auto-revert-notify-add-watch))
(auto-revert-handler)))