;;; 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
(eval-when-compile (require 'cl-lib))
(require 'timer)
+(require 'filenotify)
;; Custom Group:
;;
:type 'boolean
:version "24.4")
-(defconst auto-revert-notify-enabled
- (or (featurep 'inotify) (featurep 'w32notify))
- "Non-nil when Emacs has been compiled with file notification support.")
-
-(defcustom auto-revert-use-notify auto-revert-notify-enabled
+(defcustom auto-revert-use-notify t
"If non-nil Auto Revert Mode uses file notification functions.
-This requires Emacs being compiled with file notification
-support (see `auto-revert-notify-enabled'). You should set this
-variable through Custom."
+You should set this variable through Custom."
:group 'auto-revert
:type 'boolean
:set (lambda (variable value)
- (set-default variable (and auto-revert-notify-enabled value))
+ (set-default variable value)
(unless (symbol-value variable)
- (when auto-revert-notify-enabled
- (dolist (buf (buffer-list))
- (with-current-buffer buf
- (when (symbol-value 'auto-revert-notify-watch-descriptor)
- (auto-revert-notify-rm-watch)))))))
+ (dolist (buf (buffer-list))
+ (with-current-buffer buf
+ (when (symbol-value 'auto-revert-notify-watch-descriptor)
+ (auto-revert-notify-rm-watch))))))
:initialize 'custom-initialize-default
:version "24.4")
(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.
- (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
(puthash key value auto-revert-notify-watch-descriptor-hash-list)
(remhash key auto-revert-notify-watch-descriptor-hash-list)
(ignore-errors
- (funcall (if (fboundp 'inotify-rm-watch)
- 'inotify-rm-watch 'w32notify-rm-watch)
- auto-revert-notify-watch-descriptor)))))
+ (file-notify-rm-watch auto-revert-notify-watch-descriptor)))))
auto-revert-notify-watch-descriptor-hash-list)
(remove-hook 'kill-buffer-hook 'auto-revert-notify-rm-watch))
(setq auto-revert-notify-watch-descriptor nil
(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))
- (let ((func (if (fboundp 'inotify-add-watch)
- 'inotify-add-watch 'w32notify-add-watch))
- (aspect (if (fboundp 'inotify-add-watch)
- '(create modify moved-to) '(size last-write-time)))
- (file (if (fboundp 'inotify-add-watch)
- (directory-file-name (expand-file-name default-directory))
- (buffer-file-name))))
+ ;; 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)
+
+ (when (not auto-revert-notify-watch-descriptor)
(setq auto-revert-notify-watch-descriptor
(ignore-errors
- (funcall func file aspect 'auto-revert-notify-handler)))
+ (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
;; Fallback to file checks.
(set (make-local-variable 'auto-revert-use-notify) nil)))))
-(defun auto-revert-notify-event-p (event)
- "Check that event is a file notification event."
- (cond ((featurep 'inotify)
- (and (listp event) (= (length event) 4)))
- ((featurep 'w32notify)
- (and (listp event) (= (length event) 3) (stringp (nth 2 event))))))
-
-(defun auto-revert-notify-event-descriptor (event)
- "Return watch descriptor of file notification event, or nil."
- (and (auto-revert-notify-event-p event) (car event)))
-
-(defun auto-revert-notify-event-action (event)
- "Return action of file notification event, or nil."
- (and (auto-revert-notify-event-p event) (nth 1 event)))
-
-(defun auto-revert-notify-event-file-name (event)
- "Return file name of file notification event, or nil."
- (and (auto-revert-notify-event-p event)
- (cond ((featurep 'inotify) (nth 3 event))
- ((featurep 'w32notify) (nth 2 event)))))
+;; 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."
- (when (auto-revert-notify-event-p event)
- (let* ((descriptor (auto-revert-notify-event-descriptor event))
- (action (auto-revert-notify-event-action event))
- (file (auto-revert-notify-event-file-name event))
+ "Handle an EVENT returned from file notification."
+ (with-demoted-errors
+ (let* ((descriptor (car event))
+ (action (nth 1 event))
+ (file (nth 2 event))
+ (file1 (nth 3 event)) ;; Target of `renamed'.
(buffers (gethash descriptor
auto-revert-notify-watch-descriptor-hash-list)))
- (ignore-errors
- ;; Check, that event is meant for us.
- ;; TODO: Filter events which stop watching, like `move' or `removed'.
- (cl-assert descriptor)
- (when (featurep 'inotify)
- (cl-assert (or (memq 'create action)
- (memq 'modify action)
- (memq 'moved-to action))))
- (when (featurep 'w32notify) (cl-assert (eq 'modified action)))
- ;; Since we watch a directory, a file name must be returned.
- (cl-assert (stringp file))
- (dolist (buffer buffers)
- (when (buffer-live-p buffer)
- (with-current-buffer buffer
- (when (and (stringp buffer-file-name)
- (string-equal
- (file-name-nondirectory file)
- (file-name-nondirectory buffer-file-name)))
- ;; Mark buffer modified.
- (setq auto-revert-notify-modified-p t)
- ;; No need to check other buffers.
- (cl-return)))))))))
+ ;; Check, that event is meant for us.
+ (cl-assert descriptor)
+ ;; 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.
+ (cl-dolist (buffer buffers)
+ (when (buffer-live-p buffer)
+ (with-current-buffer buffer
+ (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))))))))
(defun auto-revert-active-p ()
"Check if auto-revert is active (in current buffer or globally)."
;; 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)
(setq size
(nth 7 (file-attributes
buffer-file-name)))))
- (and (file-readable-p buffer-file-name)
- (not (verify-visited-file-modtime buffer)))))
- (and (or auto-revert-mode
- global-auto-revert-non-file-buffers)
- revert-buffer-function
- (boundp 'buffer-stale-function)
- (functionp buffer-stale-function)
- (funcall buffer-stale-function t))))
+ (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)))