-;;; autorevert.el --- revert buffers when files on disk change
+;;; autorevert.el --- revert buffers when files on disk change -*- lexical-binding:t -*-
-;; Copyright (C) 1997-1999, 2001-2013 Free Software Foundation, Inc.
+;; Copyright (C) 1997-1999, 2001-2016 Free Software Foundation, Inc.
-;; Author: Anders Lindgren <andersl@andersl.com>
+;; Author: Anders Lindgren
;; Keywords: convenience
;; Created: 1997-06-01
;; Date: 1999-11-30
;; mode. For example, the following line will activate Auto-Revert
;; Mode in all C mode buffers:
;;
-;; (add-hook 'c-mode-hook 'turn-on-auto-revert-mode)
+;; (add-hook 'c-mode-hook #'turn-on-auto-revert-mode)
;;; Code:
(eval-when-compile (require 'cl-lib))
(require 'timer)
+(require 'filenotify)
;; Custom Group:
;;
:type 'boolean
:version "22.1")
-(defvar global-auto-revert-ignore-buffer nil
+(defvar-local global-auto-revert-ignore-buffer nil
"When non-nil, Global Auto-Revert Mode will not revert this buffer.
This variable becomes buffer local when set in any fashion.")
-(make-variable-buffer-local 'global-auto-revert-ignore-buffer)
(defcustom auto-revert-remote-files nil
"If non-nil remote files are also reverted."
:type 'boolean
:version "24.4")
-(defconst auto-revert-notify-enabled
- (or (featurep 'gfilenotify) (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")
"Position of last known end of file.")
(add-hook 'find-file-hook
- (lambda ()
- (set (make-local-variable 'auto-revert-tail-pos)
- (nth 7 (file-attributes buffer-file-name)))))
+ (lambda ()
+ (setq-local auto-revert-tail-pos
+ (nth 7 (file-attributes buffer-file-name)))))
(defvar auto-revert-notify-watch-descriptor-hash-list
(make-hash-table :test 'equal)
which are related to files being watched and carrying the same
default directory.")
-(defvar auto-revert-notify-watch-descriptor nil
+(defvar-local auto-revert-notify-watch-descriptor nil
"The file watch descriptor active for the current buffer.")
-(make-variable-buffer-local 'auto-revert-notify-watch-descriptor)
(put 'auto-revert-notify-watch-descriptor 'permanent-local t)
-(defvar auto-revert-notify-modified-p nil
+(defvar-local auto-revert-notify-modified-p nil
"Non-nil when file has been modified on the file system.
This has been reported by a file notification event.")
-(make-variable-buffer-local 'auto-revert-notify-modified-p)
;; Functions:
(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
"Turn on Auto-Revert Mode.
This function is designed to be added to hooks, for example:
- (add-hook 'c-mode-hook 'turn-on-auto-revert-mode)"
+ (add-hook \\='c-mode-hook #\\='turn-on-auto-revert-mode)"
(auto-revert-mode 1))
(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
- (set (make-local-variable 'auto-revert-tail-pos)
- (nth 7 (file-attributes buffer-file-name))))
+ (setq-local auto-revert-tail-pos
+ (nth 7 (file-attributes buffer-file-name))))
;; let auto-revert-mode set up the mechanism for us if it isn't already
(or auto-revert-mode
(let ((auto-revert-tail-mode t))
"Turn on Auto-Revert Tail mode.
This function is designed to be added to hooks, for example:
- (add-hook 'my-logfile-mode-hook 'turn-on-auto-revert-tail-mode)"
+ (add-hook \\='my-logfile-mode-hook #\\='turn-on-auto-revert-tail-mode)"
(auto-revert-tail-mode 1))
: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
(puthash key value auto-revert-notify-watch-descriptor-hash-list)
(remhash key auto-revert-notify-watch-descriptor-hash-list)
(ignore-errors
- (funcall
- (cond
- ((fboundp 'gfile-rm-watch) 'gfile-rm-watch)
- ((fboundp 'inotify-rm-watch) 'inotify-rm-watch)
- ((fboundp 'w32notify-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))
+ (remove-hook 'kill-buffer-hook #'auto-revert-notify-rm-watch))
(setq auto-revert-notify-watch-descriptor nil
auto-revert-notify-modified-p 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
- (cond
- ((fboundp 'gfile-add-watch) 'gfile-add-watch)
- ((fboundp 'inotify-add-watch) 'inotify-add-watch)
- ((fboundp 'w32notify-add-watch) 'w32notify-add-watch)))
- (aspect
- (cond
- ((fboundp 'gfile-add-watch) '(watch-mounts))
- ;; `attrib' is needed for file modification time.
- ((fboundp 'inotify-add-watch) '(attrib create modify moved-to))
- ((fboundp 'w32notify-add-watch) '(size last-write-time))))
- (file (if (or (fboundp 'gfile-add-watch) (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.
+ (setq-local 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
(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))
+ (add-hook 'kill-buffer-hook
+ #'auto-revert-notify-rm-watch nil t))
;; 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."
- (and (listp event)
- (cond ((featurep 'gfilenotify)
- (and (>= (length event) 3) (stringp (nth 2 event))))
- ((featurep 'inotify)
- (= (length event) 4))
- ((featurep 'w32notify)
- (and (= (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 'gfilenotify) (nth 2 event))
- ((featurep 'inotify) (nth 3 event))
- ((featurep 'w32notify) (nth 2 event)))))
+ (setq-local 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."
- (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))
+ (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)
- (cond
- ((featurep 'gfilenotify)
- (cl-assert (memq action '(attribute-changed changed created deleted
- ;; FIXME: I keep getting this action, so I
- ;; added it here, but I have no idea what
- ;; I'm doing. --Stef
- changes-done-hint))
- t))
- ((featurep 'inotify)
- (cl-assert (or (memq 'attrib action)
- (memq 'create action)
- (memq 'modify action)
- (memq 'moved-to action))))
- ((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)))
+
+ (if (eq action 'stopped)
+ ;; File notification has stopped. Continue with polling.
+ (cl-dolist (buffer buffers)
+ (with-current-buffer buffer
+ (when (or
+ ;; A buffer associated with a file.
+ (and (stringp buffer-file-name)
+ (string-equal
+ (file-name-nondirectory file)
+ (file-name-nondirectory buffer-file-name)))
+ ;; A buffer w/o a file, like dired.
+ (null buffer-file-name))
+ (auto-revert-notify-rm-watch)
+ (setq-local auto-revert-use-notify nil))))
+
+ ;; 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)."
(defun auto-revert-handler ()
"Revert current buffer, if appropriate.
This is an internal function used by Auto-Revert Mode."
- (when (or auto-revert-tail-mode (not (buffer-modified-p)))
- (let* ((buffer (current-buffer)) size
- ;; Tramp caches the file attributes. Setting
- ;; `remote-file-name-inhibit-cache' forces Tramp to reread
- ;; the values.
- (remote-file-name-inhibit-cache t)
- (revert
- (or (and buffer-file-name
- (or auto-revert-remote-files
- (not (file-remote-p buffer-file-name)))
- (or (not auto-revert-use-notify)
- auto-revert-notify-modified-p)
- (if auto-revert-tail-mode
- (and (file-readable-p buffer-file-name)
- (/= auto-revert-tail-pos
- (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))))
- eob eoblist)
- (setq auto-revert-notify-modified-p nil)
- (when revert
- (when (and auto-revert-verbose
- (not (eq revert 'fast)))
- (message "Reverting buffer `%s'." (buffer-name)))
- ;; If point (or a window point) is at the end of the buffer,
- ;; we want to keep it at the end after reverting. This allows
- ;; to tail a file.
- (when buffer-file-name
- (setq eob (eobp))
- (walk-windows
- (lambda (window)
- (and (eq (window-buffer window) buffer)
- (= (window-point window) (point-max))
- (push window eoblist)))
- 'no-mini t))
- (if auto-revert-tail-mode
- (auto-revert-tail-handler size)
- ;; Bind buffer-read-only in case user has done C-x C-q,
- ;; so as not to forget that. This gives undesirable results
- ;; when the file's mode changes, but that is less common.
- (let ((buffer-read-only buffer-read-only))
- (revert-buffer 'ignore-auto 'dont-ask 'preserve-modes)))
- (when buffer-file-name
- (when eob (goto-char (point-max)))
- (dolist (window eoblist)
- (set-window-point window (point-max)))))
- ;; `preserve-modes' avoids changing the (minor) modes. But we
- ;; do want to reset the mode for VC, so we do it manually.
- (when (or revert auto-revert-check-vc-info)
- (vc-find-file-hook)))))
+ (let* ((buffer (current-buffer)) size
+ ;; Tramp caches the file attributes. Setting
+ ;; `remote-file-name-inhibit-cache' forces Tramp to reread
+ ;; the values.
+ (remote-file-name-inhibit-cache t)
+ (revert
+ (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)
+ (if auto-revert-tail-mode
+ (and (file-readable-p buffer-file-name)
+ (/= auto-revert-tail-pos
+ (setq size
+ (nth 7 (file-attributes
+ buffer-file-name)))))
+ (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
+ (when (and auto-revert-verbose
+ (not (eq revert 'fast)))
+ (message "Reverting buffer `%s'." (buffer-name)))
+ ;; If point (or a window point) is at the end of the buffer, we
+ ;; want to keep it at the end after reverting. This allows to
+ ;; tail a file.
+ (when buffer-file-name
+ (setq eob (eobp))
+ (walk-windows
+ (lambda (window)
+ (and (eq (window-buffer window) buffer)
+ (= (window-point window) (point-max))
+ (push window eoblist)))
+ 'no-mini t))
+ (if auto-revert-tail-mode
+ (auto-revert-tail-handler size)
+ ;; Bind buffer-read-only in case user has done C-x C-q, so as
+ ;; not to forget that. This gives undesirable results when
+ ;; the file's mode changes, but that is less common.
+ (let ((buffer-read-only buffer-read-only))
+ (revert-buffer 'ignore-auto 'dont-ask 'preserve-modes)))
+ (when buffer-file-name
+ (when eob (goto-char (point-max)))
+ (dolist (window eoblist)
+ (set-window-point window (point-max)))))
+ ;; `preserve-modes' avoids changing the (minor) modes. But we do
+ ;; want to reset the mode for VC, so we do it manually.
+ (when (or revert auto-revert-check-vc-info)
+ (vc-refresh-state))))
(defun auto-revert-tail-handler (size)
(let ((modified (buffer-modified-p))
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)))