diff options
Diffstat (limited to 'lisp/autorevert.el')
| -rw-r--r-- | lisp/autorevert.el | 424 |
1 files changed, 276 insertions, 148 deletions
diff --git a/lisp/autorevert.el b/lisp/autorevert.el index 58c5dba3160..5c79a7e7955 100644 --- a/lisp/autorevert.el +++ b/lisp/autorevert.el @@ -107,7 +107,7 @@ ;; Dependencies: -(eval-when-compile (require 'cl-lib)) +(require 'cl-lib) (require 'timer) (require 'filenotify) @@ -126,8 +126,6 @@ Global Auto-Revert Mode does so in all buffers." ;; Variables: -;;; What's this?: ;; Autoload for the benefit of `make-mode-line-mouse-sensitive'. -;;; What's this?: ;;;###autoload (defvar auto-revert-mode nil "Non-nil when Auto-Revert Mode is active. Never set this variable directly, use the command `auto-revert-mode' instead.") @@ -302,6 +300,27 @@ You should set this variable through Custom." :type 'regexp :version "24.4") +(defcustom auto-revert-avoid-polling nil + "Non-nil to avoid polling files when notification is available. + +Set this variable to a non-nil value to save power by avoiding +polling when possible. Files on file-systems that do not support +change notifications must match `auto-revert-notify-exclude-dir-regexp' +for Auto-Revert to work properly in this case. This typically +includes files on network file systems on Unix-like machines, +when those files are modified from another computer. + +When nil, buffers in Auto-Revert Mode will always be polled for +changes to their files on disk every `auto-revert-interval' +seconds, in addition to using notification for those files." + :group 'auto-revert + :type 'boolean + :set (lambda (variable value) + (set-default variable value) + (when (fboundp 'auto-revert-set-timer) + (auto-revert-set-timer))) + :version "27.1") + ;; Internal variables: (defvar auto-revert-buffer-list () @@ -313,6 +332,9 @@ buffers to this list. The timer function `auto-revert-buffers' is responsible for purging the list of old buffers.") +(defvar-local auto-revert--global-mode nil + "Non-nil if buffer is handled by Global Auto-Revert mode.") + (defvar auto-revert-remaining-buffers () "Buffers not checked when user input stopped execution.") @@ -321,17 +343,19 @@ the list of old buffers.") (defun auto-revert-find-file-function () (setq-local auto-revert-tail-pos - (nth 7 (file-attributes buffer-file-name)))) + (file-attribute-size (file-attributes buffer-file-name)))) (add-hook 'find-file-hook #'auto-revert-find-file-function) +(add-hook 'after-set-visited-file-name-hook + #'auto-revert-set-visited-file-name) -(defvar auto-revert-notify-watch-descriptor-hash-list +(defvar auto-revert--buffers-by-watch-descriptor (make-hash-table :test 'equal) - "A hash table collecting all file watch descriptors. -Hash key is a watch descriptor, hash value is a list of buffers -which are related to files being watched and carrying the same -default directory.") + "A hash table mapping notification descriptors to lists of buffers. +The buffers use that descriptor for auto-revert notifications. +The key is equal to `auto-revert-notify-watch-descriptor' in each +buffer.") (defvar-local auto-revert-notify-watch-descriptor nil "The file watch descriptor active for the current buffer.") @@ -341,19 +365,20 @@ default directory.") "Non-nil when file has been modified on the file system. This has been reported by a file notification event.") +(defvar auto-revert-debug nil + "Use for debug messages.") + ;; Functions: -(defun auto-revert-remove-current-buffer () - "Remove dead buffer from `auto-revert-buffer-list'." +(defun auto-revert-remove-current-buffer (&optional buffer) + "Remove BUFFER from `auto-revert-buffer-list'. +BUFFER defaults to `current-buffer'." (setq auto-revert-buffer-list - (delq (current-buffer) auto-revert-buffer-list))) + (delq (or buffer (current-buffer)) auto-revert-buffer-list))) ;;;###autoload (define-minor-mode auto-revert-mode "Toggle reverting buffer when the file changes (Auto-Revert Mode). -With a prefix argument ARG, enable Auto-Revert Mode if ARG is -positive, and disable it otherwise. If called from Lisp, enable -the mode if ARG is omitted or nil. Auto-Revert Mode is a minor mode that affects only the current buffer. When enabled, it reverts the buffer when the file on @@ -373,7 +398,7 @@ without being changed in the part that is already in the buffer." 'kill-buffer-hook #'auto-revert-remove-current-buffer nil t)) - (when auto-revert-use-notify (auto-revert-notify-rm-watch)) + (when auto-revert-notify-watch-descriptor (auto-revert-notify-rm-watch)) (auto-revert-remove-current-buffer)) (auto-revert-set-timer) (when auto-revert-mode @@ -393,9 +418,6 @@ This function is designed to be added to hooks, for example: ;;;###autoload (define-minor-mode auto-revert-tail-mode "Toggle reverting tail of buffer when the file grows. -With a prefix argument ARG, enable Auto-Revert Tail Mode if ARG -is positive, and disable it otherwise. If called from Lisp, -enable the mode if ARG is omitted or nil. When Auto-Revert Tail Mode is enabled, the tail of the file is constantly followed, as with the shell command `tail -f'. This @@ -440,7 +462,8 @@ Perform a full revert? ") (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 (setq-local auto-revert-tail-pos - (nth 7 (file-attributes buffer-file-name)))) + (file-attribute-size + (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)) @@ -460,9 +483,6 @@ This function is designed to be added to hooks, for example: ;;;###autoload (define-minor-mode global-auto-revert-mode "Toggle Global Auto-Revert Mode. -With a prefix argument ARG, enable Global Auto-Revert Mode if ARG -is positive, and disable it otherwise. If called from Lisp, -enable the mode if ARG is omitted or nil. Global Auto-Revert Mode is a global minor mode that reverts any buffer associated with a file when the file changes on disk. Use @@ -483,11 +503,106 @@ specifies in the mode line." :global t :group 'auto-revert :lighter global-auto-revert-mode-text (auto-revert-set-timer) (if global-auto-revert-mode - (auto-revert-buffers) + ;; Turn global-auto-revert-mode ON. + (progn + (dolist (buf (buffer-list)) + (with-current-buffer buf + (auto-revert--global-add-current-buffer))) + ;; Make sure future buffers are added as well. + (add-hook 'find-file-hook #'auto-revert--global-adopt-current-buffer) + ;; To track non-file buffers, we need to listen in to buffer + ;; creation in general. Listening to major-mode changes is + ;; suitable, since we then know whether it's a mode that is tracked. + (when global-auto-revert-non-file-buffers + (add-hook 'after-change-major-mode-hook + #'auto-revert--global-adopt-current-buffer)) + (auto-revert-buffers)) + ;; Turn global-auto-revert-mode OFF. + (remove-hook 'after-change-major-mode-hook + #'auto-revert--global-adopt-current-buffer) + (remove-hook 'find-file-hook #'auto-revert--global-adopt-current-buffer) (dolist (buf (buffer-list)) (with-current-buffer buf - (when auto-revert-use-notify - (auto-revert-notify-rm-watch)))))) + (when auto-revert--global-mode + (setq auto-revert--global-mode nil) + (when (and auto-revert-notify-watch-descriptor + (not (or auto-revert-mode auto-revert-tail-mode))) + (auto-revert-notify-rm-watch))))))) + +(defun auto-revert--global-add-current-buffer () + "Set current buffer to be tracked by Global Auto-Revert if appropriate." + (when (and (not auto-revert--global-mode) + (or buffer-file-name + (and global-auto-revert-non-file-buffers + (not (string-prefix-p " " (buffer-name))) + ;; Any non-file buffer must have a custom + ;; `buffer-stale-function' to be tracked, since + ;; we wouldn't know when to revert it otherwise. + (not (eq buffer-stale-function + #'buffer-stale--default-function)))) + (not (memq 'major-mode global-auto-revert-ignore-modes)) + (not global-auto-revert-ignore-buffer)) + (setq auto-revert--global-mode t))) + +(defun auto-revert--global-adopt-current-buffer () + "Consider tracking current buffer in a running Global Auto-Revert mode." + (auto-revert--global-add-current-buffer) + (auto-revert-set-timer)) + +(defun auto-revert-set-visited-file-name () + "Update Auto-Revert management of the current buffer. +Called after `set-visited-file-name'." + (when auto-revert-notify-watch-descriptor + ;; Remove any existing notifier so that we don't track the wrong + ;; file in case the file name was changed. + (auto-revert-notify-rm-watch)) + (cond (global-auto-revert-mode + (auto-revert--global-adopt-current-buffer)) + ((or auto-revert-mode auto-revert-tail-mode) + (auto-revert-set-timer)))) + +(defun auto-revert--polled-buffers () + "List of buffers that need to be polled." + (cond (global-auto-revert-mode + (mapcan (lambda (buffer) + (and (not (and auto-revert-avoid-polling + (buffer-local-value + 'auto-revert-notify-watch-descriptor + buffer))) + (or (buffer-local-value + 'auto-revert--global-mode buffer) + (buffer-local-value 'auto-revert-mode buffer) + (buffer-local-value 'auto-revert-tail-mode buffer)) + (list buffer))) + (buffer-list))) + (auto-revert-avoid-polling + (mapcan (lambda (buffer) + (and (not (buffer-local-value + 'auto-revert-notify-watch-descriptor buffer)) + (list buffer))) + auto-revert-buffer-list)) + (t auto-revert-buffer-list))) + +;; Same as above in a boolean context, but cheaper. +(defun auto-revert--need-polling-p () + "Whether periodic polling is required." + (cond (global-auto-revert-mode + (or (not auto-revert-avoid-polling) + (cl-some + (lambda (buffer) + (and (not (buffer-local-value + 'auto-revert-notify-watch-descriptor buffer)) + (or (buffer-local-value 'auto-revert--global-mode buffer) + (buffer-local-value 'auto-revert-mode buffer) + (buffer-local-value 'auto-revert-tail-mode buffer)))) + (buffer-list)))) + (auto-revert-avoid-polling + (not (cl-every + (lambda (buffer) + (buffer-local-value + 'auto-revert-notify-watch-descriptor buffer)) + auto-revert-buffer-list))) + (t auto-revert-buffer-list))) (defun auto-revert-set-timer () "Restart or cancel the timer used by Auto-Revert Mode. @@ -499,87 +614,86 @@ will use an up-to-date value of `auto-revert-interval'" (if (timerp auto-revert-timer) (cancel-timer auto-revert-timer)) (setq auto-revert-timer - (if (or global-auto-revert-mode auto-revert-buffer-list) - (run-with-timer auto-revert-interval - auto-revert-interval - 'auto-revert-buffers)))) + (and (auto-revert--need-polling-p) + (run-with-timer auto-revert-interval + auto-revert-interval + 'auto-revert-buffers)))) (defun auto-revert-notify-rm-watch () "Disable file notification for current buffer's associated file." - (when auto-revert-notify-watch-descriptor - (maphash - (lambda (key value) - (when (equal key auto-revert-notify-watch-descriptor) - (setq value (delete (current-buffer) value)) - (if value - (puthash key value auto-revert-notify-watch-descriptor-hash-list) - (remhash key auto-revert-notify-watch-descriptor-hash-list) - (ignore-errors - (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)) + (let ((desc auto-revert-notify-watch-descriptor) + (table auto-revert--buffers-by-watch-descriptor)) + (when desc + (let ((buffers (delq (current-buffer) (gethash desc table)))) + (if buffers + (puthash desc buffers table) + (remhash desc table))) + (ignore-errors + (file-notify-rm-watch desc)) + (remove-hook 'kill-buffer-hook #'auto-revert-notify-rm-watch t))) (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." - ;; 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 - (if buffer-file-name - (file-notify-add-watch - (expand-file-name buffer-file-name default-directory) - '(change attribute-change) - 'auto-revert-notify-handler) + ;; We can assume that `auto-revert-notify-watch-descriptor' is nil. + (unless (or auto-revert-notify-watch-descriptor + (string-match auto-revert-notify-exclude-dir-regexp + (expand-file-name default-directory)) + (file-symlink-p (or buffer-file-name default-directory))) + ;; Check, whether this has been activated already. + (let ((file (if buffer-file-name + (expand-file-name buffer-file-name default-directory) + (expand-file-name default-directory)))) + (maphash + (lambda (key _value) + (when (and + (file-notify-valid-p key) + (equal (file-notify--watch-absolute-filename + (gethash key file-notify-descriptors)) + (directory-file-name file)) + (equal (file-notify--watch-callback + (gethash key file-notify-descriptors)) + 'auto-revert-notify-handler)) + (setq auto-revert-notify-watch-descriptor key))) + auto-revert--buffers-by-watch-descriptor) + ;; Create a new watch if needed. + (unless auto-revert-notify-watch-descriptor + (setq auto-revert-notify-watch-descriptor + (ignore-errors (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 'kill-buffer-hook - #'auto-revert-notify-rm-watch nil t)) - ;; Fallback to file checks. - (setq-local auto-revert-use-notify nil))))) + file + (if buffer-file-name '(change attribute-change) '(change)) + 'auto-revert-notify-handler)))) + (when auto-revert-notify-watch-descriptor + (setq auto-revert-notify-modified-p t) + (puthash + auto-revert-notify-watch-descriptor + (cons (current-buffer) + (gethash auto-revert-notify-watch-descriptor + auto-revert--buffers-by-watch-descriptor)) + auto-revert--buffers-by-watch-descriptor) + (add-hook 'kill-buffer-hook #'auto-revert-notify-rm-watch nil t))))) ;; 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'") +;; We do this by reverting immediately in response to the first in a +;; flurry of notifications. Any notifications during the following +;; `auto-revert-lockout-interval' seconds are noted but not acted upon +;; until the end of that interval. + +(defconst auto-revert--lockout-interval 2.5 + "Duration, in seconds, of the Auto-Revert Mode notification lockout. +This is the quiescence after each notification of a file being +changed during which no automatic reverting takes place, to +prevent many updates in rapid succession from overwhelming the +system.") + +(defvar-local auto-revert--lockout-timer nil + "Timer awaiting the end of the notification lockout interval, or nil.") (defun auto-revert-notify-handler (event) "Handle an EVENT returned from file notification." @@ -589,30 +703,31 @@ no more reverts are possible until the next call of (file (nth 2 event)) (file1 (nth 3 event)) ;; Target of `renamed'. (buffers (gethash descriptor - auto-revert-notify-watch-descriptor-hash-list))) + auto-revert--buffers-by-watch-descriptor))) ;; 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))) + (when auto-revert-debug + (message "auto-revert-notify-handler %S" event)) (if (eq action 'stopped) ;; File notification has stopped. Continue with polling. - (cl-dolist (buffer - (if global-auto-revert-mode - (buffer-list) auto-revert-buffer-list)) + (cl-dolist (buffer buffers) (with-current-buffer buffer - (when (and (equal descriptor auto-revert-notify-watch-descriptor) - (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))) + (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)))) + ;; Restart the timer if it wasn't running. + (unless auto-revert-timer) + (auto-revert-set-timer)))) ;; Loop over all buffers, in order to find the intended one. (cl-dolist (buffer buffers) @@ -638,24 +753,27 @@ no more reverts are possible until the next call of (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) + (unless auto-revert--lockout-timer (auto-revert-handler) - (setq auto-revert-buffers-counter-lockedout - auto-revert-buffers-counter)) - - ;; No need to check other buffers. - (cl-return))))))))) + (setq auto-revert--lockout-timer + (run-with-timer + auto-revert--lockout-interval nil + #'auto-revert--end-lockout buffer))))))))))) + +(defun auto-revert--end-lockout (buffer) + "End the lockout period after a notification. +If the buffer needs to be reverted, do it now." + (when (buffer-live-p buffer) + (with-current-buffer buffer + (setq auto-revert--lockout-timer nil) + (when auto-revert-notify-modified-p + (auto-revert-handler))))) (defun auto-revert-active-p () - "Check if auto-revert is active (in current buffer or globally)." + "Check if auto-revert is active in current buffer." (or auto-revert-mode auto-revert-tail-mode - (and - global-auto-revert-mode - (not global-auto-revert-ignore-buffer) - (not (memq major-mode - global-auto-revert-ignore-modes))))) + auto-revert--global-mode)) (defun auto-revert-handler () "Revert current buffer, if appropriate. @@ -669,14 +787,14 @@ This is an internal function used by Auto-Revert Mode." (if buffer-file-name (and (or auto-revert-remote-files (not (file-remote-p buffer-file-name))) - (or (not auto-revert-use-notify) + (or (not auto-revert-notify-watch-descriptor) 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))))) + (file-attribute-size + (file-attributes buffer-file-name))))) (funcall (or buffer-stale-function #'buffer-stale--default-function) t))) @@ -719,7 +837,8 @@ This is an internal function used by Auto-Revert Mode." ;; `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)))) + (let ((revert-buffer-in-progress-p t)) + (vc-refresh-state))))) (defun auto-revert-tail-handler (size) (let ((modified (buffer-modified-p)) @@ -767,14 +886,21 @@ 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)) + (let ((bufs (auto-revert--polled-buffers)) remaining new) + ;; Buffers with remote contents shall be reverted only if the + ;; connection is established already. + (setq bufs (delq nil + (mapcar + (lambda (buf) + (and (buffer-live-p buf) + (with-current-buffer buf + (and + (or (not (file-remote-p default-directory)) + (file-remote-p default-directory nil t)) + buf)))) + bufs))) ;; 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 @@ -790,29 +916,31 @@ the timer when no buffers need to be checked." (not (and auto-revert-stop-on-user-input (input-pending-p)))) (let ((buf (car bufs))) - (with-current-buffer buf - (if (buffer-live-p buf) - (progn - ;; Test if someone has turned off Auto-Revert Mode - ;; in a non-standard way, for example by changing - ;; major mode. - (if (and (not auto-revert-mode) - (not auto-revert-tail-mode) - (memq buf auto-revert-buffer-list)) - (auto-revert-remove-current-buffer)) - (when (auto-revert-active-p) - ;; Enable file notification. - (when (and auto-revert-use-notify - (not auto-revert-notify-watch-descriptor)) - (auto-revert-notify-add-watch)) - (auto-revert-handler))) + (if (not (buffer-live-p buf)) ;; Remove dead buffer from `auto-revert-buffer-list'. - (auto-revert-remove-current-buffer)))) + (auto-revert-remove-current-buffer buf) + (with-current-buffer buf + ;; Test if someone has turned off Auto-Revert Mode + ;; in a non-standard way, for example by changing + ;; major mode. + (if (and (not auto-revert-mode) + (not auto-revert-tail-mode) + (memq buf auto-revert-buffer-list)) + (auto-revert-remove-current-buffer)) + (when (auto-revert-active-p) + ;; Enable file notification. + ;; Don't bother creating a notifier for non-file buffers + ;; unless it explicitly indicates that this works. + (when (and auto-revert-use-notify + (not auto-revert-notify-watch-descriptor) + (or buffer-file-name + buffer-auto-revert-by-notification)) + (auto-revert-notify-add-watch)) + (auto-revert-handler))))) (setq bufs (cdr bufs))) (setq auto-revert-remaining-buffers bufs) ;; Check if we should cancel the timer. - (when (and (not global-auto-revert-mode) - (null auto-revert-buffer-list)) + (unless (auto-revert--need-polling-p) (if (timerp auto-revert-timer) (cancel-timer auto-revert-timer)) (setq auto-revert-timer nil))))) |