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

;;; autorevert --- revert buffers when files on disk change

;; Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.

;; Author: Anders Lindgren <andersl@andersl.com>
;; Keywords: convenience
;; Created: 1997-06-01
;; Date: 1999-11-30

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Commentary:

;; Introduction:
;;
;; Whenever a file that Emacs is editing has been changed by another
;; program the user normally has to execute the command `revert-buffer'
;; to load the new content of the file into Emacs.
;;
;; This package contains two minor modes: Global Auto-Revert Mode and
;; Auto-Revert Mode.  Both modes automatically revert buffers
;; whenever the corresponding files have been changed on disk.
;;
;; Auto-Revert Mode can be activated for individual buffers.
;; Global Auto-Revert Mode applies to all file buffers.
;;
;; Both modes operate by checking the time stamp of all files at
;; intervals of `auto-revert-interval'.  The default is every five
;; seconds.  The check is aborted whenever the user actually uses
;; Emacs.  You should never even notice that this package is active
;; (except that your buffers will be reverted, of course).

;; Usage:
;;
;; Go to the appropriate buffer and press:
;;   M-x auto-revert-mode RET
;;
;; To activate Global Auto-Revert Mode, press:
;;   M-x global-auto-revert-mode RET
;;
;; To activate Global Auto-Revert Mode every time Emacs is started
;; customise the option `global-auto-revert-mode' or the following
;; line could be added to your ~/.emacs:
;;   (global-auto-revert-mode 1)
;;
;; The function `turn-on-auto-revert-mode' could be added to any major
;; mode hook to activate Auto-Revert Mode for all buffers in that
;; 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)

;;; Code:

;; Dependencies:

(require 'timer)
(eval-when-compile (require 'cl))


;; Custom Group:
;;
;; The two modes will be placed next to Auto Save Mode under the
;; Files group under Emacs.

(defgroup auto-revert nil
  "Revert individual buffers when files on disk change.

Auto-Revert Mode can be activated for individual buffer.
Global Auto-Revert Mode applies to all buffers."
  :group 'files
  :group 'convenience)


;; Variables:

;; Autoload for the benefit of `make-mode-line-mouse-sensitive'.
;;;###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.")

;;;###autoload
(defcustom global-auto-revert-mode nil
  "When on, buffers are automatically reverted when files on disk change.

Set this variable using \\[customize] only.  Otherwise, use the
command `global-auto-revert-mode'."
  :group 'auto-revert
  :initialize 'custom-initialize-default
  :set '(lambda (symbol value)
	  (global-auto-revert-mode (or value 0)))
  :type 'boolean
  :require 'autorevert)

(defcustom auto-revert-interval 5
  "Time, in seconds, between Auto-Revert Mode file checks."
  :group 'auto-revert
  :type 'integer)

(defcustom auto-revert-stop-on-user-input t
  "When non-nil Auto-Revert Mode stops checking files on user input."
  :group 'auto-revert
  :type 'boolean)

(defcustom auto-revert-verbose t
  "When nil, Auto-Revert Mode will not generate any messages.

Currently, messages are generated when the mode is activated or
deactivated, and whenever a file is reverted."
  :group 'auto-revert
  :type 'boolean)

(defcustom auto-revert-mode-text " ARev"
  "String to display in the mode line when Auto-Revert Mode is active.

\(When the string is not empty, make sure that it has a leading space.)"
  :tag "Auto Revert Mode Text"		; To separate it from `global-...'
  :group 'auto-revert
  :type 'string)

(defcustom auto-revert-mode-hook nil
  "Functions to run when Auto-Revert Mode is activated."
  :tag "Auto Revert Mode Hook"		; To separate it from `global-...'
  :group 'auto-revert
  :type 'hook)

(defcustom global-auto-revert-mode-text ""
  "String to display when Global Auto-Revert Mode is active.

The default is nothing since when this mode is active this text doesn't
vary over time, or between buffers.  Hence mode line text
would only waste precious space."
  :group 'auto-revert
  :type 'string)

(defcustom global-auto-revert-mode-hook nil
  "Hook called when Global Auto-Revert Mode is activated."
  :group 'auto-revert
  :type 'hook)

(defcustom global-auto-revert-non-file-buffers nil
  "*When nil only file buffers are reverted by Global Auto-Revert Mode.

When non-nil, both file buffers and buffers with a custom
`revert-buffer-function' are reverted by Global Auto-Revert Mode."
  :group 'auto-revert
  :type 'boolean)

(defcustom global-auto-revert-non-file-buffers nil
  "When nil only file buffers are reverted by Global Auto-Revert Mode.

When non-nil, both file buffers and buffers with a custom
`revert-buffer-function' are reverted by Global Auto-Revert Mode.

Use this option with care since it could lead to excessive reverts."
  :group 'auto-revert
  :type 'boolean)

(defcustom global-auto-revert-ignore-modes '()
  "List of major modes Global Auto-Revert Mode should not check."
  :group 'auto-revert
  :type '(repeat sexp))

(defcustom auto-revert-load-hook nil
  "Functions to run when Auto-Revert Mode is first loaded."
  :tag "Load Hook"
  :group 'auto-revert
  :type 'hook)

(defvar 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)


;; Internal variables:

(defvar auto-revert-buffer-list '()
  "List of buffers in Auto-Revert Mode.

Note that only Auto-Revert Mode, never Global Auto-Revert Mode, adds
buffers to this list.

The timer function `auto-revert-buffers' is responsible for purging
the list of old buffers.")

(defvar auto-revert-timer nil
  "Timer used by Auto-Revert Mode.")

(defvar auto-revert-remaining-buffers '()
  "Buffers not checked when user input stopped execution.")


;; Functions:

;;;###autoload
(defun auto-revert-mode (&optional arg)
  "Toggle reverting buffer when file on disk changes.

With arg, turn Auto Revert mode on if and only if arg is positive.
This is a minor mode that affects only the current buffer.
Use `global-auto-revert-mode' to automatically revert all buffers."
  (interactive "P")
  (make-local-variable 'auto-revert-mode)
  (put 'auto-revert-mode 'permanent-local t)
  (setq auto-revert-mode
	(if (null arg)
	    (not auto-revert-mode)
	  (> (prefix-numeric-value arg) 0)))
  (if (and auto-revert-verbose
	   (interactive-p))
      (message "Auto-Revert Mode is now %s."
	       (if auto-revert-mode "on" "off")))
  (if auto-revert-mode
      (if (not (memq (current-buffer) auto-revert-buffer-list))
	  (push (current-buffer) auto-revert-buffer-list))
    (setq auto-revert-buffer-list
	  (delq (current-buffer) auto-revert-buffer-list)))
  (auto-revert-set-timer)
  (when auto-revert-mode
    (auto-revert-buffers)
    (run-hooks 'auto-revert-mode-hook))
  auto-revert-mode)


;;;###autoload
(defun turn-on-auto-revert-mode ()
  "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)"
  (auto-revert-mode 1))


;;;###autoload
(defun global-auto-revert-mode (&optional arg)
  "Revert any buffer when file on disk change.

With arg, turn Auto Revert mode on globally if and only if arg is positive.
This is a minor mode that affects all buffers.
Use `auto-revert-mode' to revert a particular buffer."
  (interactive "P")
  (setq global-auto-revert-mode
	(if (null arg)
	    (not global-auto-revert-mode)
	  (> (prefix-numeric-value arg) 0)))
  (if (and auto-revert-verbose
	   (interactive-p))
      (message "Global Auto-Revert Mode is now %s."
	       (if global-auto-revert-mode "on" "off")))
  (auto-revert-set-timer)
  (when global-auto-revert-mode
    (auto-revert-buffers)      
    (run-hooks 'global-auto-revert-mode-hook)))


(defun auto-revert-set-timer ()
  "Restart or cancel the timer."
  (if (timerp auto-revert-timer)
      (cancel-timer auto-revert-timer))
  (if (or global-auto-revert-mode auto-revert-buffer-list)
      (setq auto-revert-timer (run-with-timer auto-revert-interval
					      auto-revert-interval
					      'auto-revert-buffers))
    (setq auto-revert-timer nil)))


(defun auto-revert-buffers ()
  "Revert buffers as specified by Auto-Revert and Global Auto-Revert Mode.

Should `global-auto-revert-mode' be active all file buffers are checked.

Should `auto-revert-mode' be active in some buffers, those buffers
are checked.

Non-file buffers that have a custom `revert-buffer-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 stops whenever there is user input.  The buffers not
checked are stored in the variable `auto-revert-remaining-buffers'.

To avoid starvation, the buffers in `auto-revert-remaining-buffers'
are checked first the next time this function is called.

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."
  (let ((bufs (if global-auto-revert-mode
		  (buffer-list)
		auto-revert-buffer-list))
	(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
    ;; head of the list.
    (dolist (buf auto-revert-remaining-buffers)
      (if (memq buf bufs)
	  (push buf remaining)))
    (dolist (buf bufs)
      (if (not (memq buf remaining))
	  (push buf new)))
    (setq bufs (nreverse (nconc new remaining)))
    (while (and bufs
		(not (and auto-revert-stop-on-user-input
			  (input-pending-p))))
      (let ((buf (car bufs)))
	(if (buffer-name buf)		; Buffer still alive?
	    (save-excursion
	      (set-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)
		       (memq buf auto-revert-buffer-list))
		  (setq auto-revert-buffer-list
			(delq buf auto-revert-buffer-list)))
	      (when (and
		     (or auto-revert-mode
			 (and
			  global-auto-revert-mode
			  (not global-auto-revert-ignore-buffer)
			  (not (memq major-mode
				     global-auto-revert-ignore-modes))))
		     (not (buffer-modified-p))
		     (if (buffer-file-name)
			 (and (file-readable-p (buffer-file-name))
			      (not (verify-visited-file-modtime buf)))
		       (and revert-buffer-function
			    (or (and global-auto-revert-mode
				     global-auto-revert-non-file-buffers)
				auto-revert-mode))))
		(if auto-revert-verbose
		    (message "Reverting buffer `%s'." buf))
		(revert-buffer t t t)))
	  ;; Remove dead buffer from `auto-revert-buffer-list'.
	  (setq auto-revert-buffer-list
		(delq buf auto-revert-buffer-list))))
      (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))
      (cancel-timer auto-revert-timer)
      (setq auto-revert-timer nil))))


;; The end:

(unless (assq 'auto-revert-mode minor-mode-alist)
  (push '(auto-revert-mode auto-revert-mode-text)
	minor-mode-alist))
(unless (assq 'global-auto-revert-mode minor-mode-alist)
  (push '(global-auto-revert-mode global-auto-revert-mode-text)
	minor-mode-alist))

(provide 'autorevert)

(run-hooks 'auto-revert-load-hook)

;; This makes it possible to set Global Auto-Revert Mode from
;; Customize.
(if global-auto-revert-mode
    (global-auto-revert-mode 1))

;; autorevert.el ends here.
Commit	Line	Data
5abdc915	1	;;; autorevert --- revert buffers when files on disk change
4a35aff3	2
a468671a	3	;; Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.
4a35aff3	4
a468671a	5	;; Author: Anders Lindgren <andersl@andersl.com>
f5f727f8	6	;; Keywords: convenience
a468671a GM	7	;; Created: 1997-06-01
a468671a GM	8	;; Date: 1999-11-30
4a35aff3 RS	9
	10	;; This file is part of GNU Emacs.
	11
	12	;; GNU Emacs is free software; you can redistribute it and/or modify
	13	;; it under the terms of the GNU General Public License as published by
	14	;; the Free Software Foundation; either version 2, or (at your option)
	15	;; any later version.
	16
	17	;; GNU Emacs is distributed in the hope that it will be useful,
	18	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	20	;; GNU General Public License for more details.
	21
	22	;; You should have received a copy of the GNU General Public License
	23	;; along with GNU Emacs; see the file COPYING. If not, write to the
	24	;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	25	;; Boston, MA 02111-1307, USA.
	26
	27	;;; Commentary:
	28
	29	;; Introduction:
	30	;;
	31	;; Whenever a file that Emacs is editing has been changed by another
48764ae2	32	;; program the user normally has to execute the command `revert-buffer'
4a35aff3 RS	33	;; to load the new content of the file into Emacs.
	34	;;
	35	;; This package contains two minor modes: Global Auto-Revert Mode and
48764ae2	36	;; Auto-Revert Mode. Both modes automatically revert buffers
4a35aff3 RS	37	;; whenever the corresponding files have been changed on disk.
	38	;;
	39	;; Auto-Revert Mode can be activated for individual buffers.
	40	;; Global Auto-Revert Mode applies to all file buffers.
	41	;;
48764ae2 DL	42	;; Both modes operate by checking the time stamp of all files at
	43	;; intervals of `auto-revert-interval'. The default is every five
	44	;; seconds. The check is aborted whenever the user actually uses
	45	;; Emacs. You should never even notice that this package is active
	46	;; (except that your buffers will be reverted, of course).
4a35aff3 RS	47
	48	;; Usage:
	49	;;
	50	;; Go to the appropriate buffer and press:
	51	;; M-x auto-revert-mode RET
	52	;;
	53	;; To activate Global Auto-Revert Mode, press:
	54	;; M-x global-auto-revert-mode RET
	55	;;
48764ae2 DL	56	;; To activate Global Auto-Revert Mode every time Emacs is started
	57	;; customise the option `global-auto-revert-mode' or the following
	58	;; line could be added to your ~/.emacs:
4a35aff3 RS	59	;; (global-auto-revert-mode 1)
	60	;;
	61	;; The function `turn-on-auto-revert-mode' could be added to any major
	62	;; mode hook to activate Auto-Revert Mode for all buffers in that
	63	;; mode. For example, the following line will activate Auto-Revert
	64	;; Mode in all C mode buffers:
	65	;;
	66	;; (add-hook 'c-mode-hook 'turn-on-auto-revert-mode)
	67
	68	;;; Code:
	69
	70	;; Dependencies:
	71
	72	(require 'timer)
	73	(eval-when-compile (require 'cl))
	74
	75
	76	;; Custom Group:
	77	;;
	78	;; The two modes will be placed next to Auto Save Mode under the
	79	;; Files group under Emacs.
	80
	81	(defgroup auto-revert nil
48764ae2	82	"Revert individual buffers when files on disk change.
4a35aff3 RS	83
	84	Auto-Revert Mode can be activated for individual buffer.
	85	Global Auto-Revert Mode applies to all buffers."
f5f727f8 DN	86	:group 'files
f5f727f8 DN	87	:group 'convenience)
4a35aff3 RS	88
	89
	90	;; Variables:
	91
00d0fda8 DL	92	;; Autoload for the benefit of `make-mode-line-mouse-sensitive'.
00d0fda8 DL	93	;;;###autoload
4a35aff3 RS	94	(defvar auto-revert-mode nil
	95	"*Non-nil when Auto-Revert Mode is active.
	96
48764ae2 DL	97	Never set this variable directly, use the command `auto-revert-mode'
48764ae2 DL	98	instead.")
4a35aff3	99
6ea3b61f	100	;;;###autoload
4a35aff3 RS	101	(defcustom global-auto-revert-mode nil
	102	"When on, buffers are automatically reverted when files on disk change.
	103
48764ae2 DL	104	Set this variable using \\[customize] only. Otherwise, use the
48764ae2 DL	105	command `global-auto-revert-mode'."
4a35aff3 RS	106	:group 'auto-revert
	107	:initialize 'custom-initialize-default
	108	:set '(lambda (symbol value)
	109	(global-auto-revert-mode (or value 0)))
	110	:type 'boolean
	111	:require 'autorevert)
	112
	113	(defcustom auto-revert-interval 5
	114	"Time, in seconds, between Auto-Revert Mode file checks."
	115	:group 'auto-revert
	116	:type 'integer)
	117
	118	(defcustom auto-revert-stop-on-user-input t
	119	"When non-nil Auto-Revert Mode stops checking files on user input."
	120	:group 'auto-revert
	121	:type 'boolean)
	122
	123	(defcustom auto-revert-verbose t
	124	"When nil, Auto-Revert Mode will not generate any messages.
	125
	126	Currently, messages are generated when the mode is activated or
	127	deactivated, and whenever a file is reverted."
	128	:group 'auto-revert
	129	:type 'boolean)
	130
	131	(defcustom auto-revert-mode-text " ARev"
	132	"String to display in the mode line when Auto-Revert Mode is active.
	133
	134	\(When the string is not empty, make sure that it has a leading space.)"
	135	:tag "Auto Revert Mode Text" ; To separate it from `global-...'
	136	:group 'auto-revert
	137	:type 'string)
	138
	139	(defcustom auto-revert-mode-hook nil
	140	"Functions to run when Auto-Revert Mode is activated."
	141	:tag "Auto Revert Mode Hook" ; To separate it from `global-...'
	142	:group 'auto-revert
	143	:type 'hook)
	144
	145	(defcustom global-auto-revert-mode-text ""
	146	"String to display when Global Auto-Revert Mode is active.
	147
	148	The default is nothing since when this mode is active this text doesn't
48764ae2	149	vary over time, or between buffers. Hence mode line text
4a35aff3 RS	150	would only waste precious space."
	151	:group 'auto-revert
	152	:type 'string)
	153
	154	(defcustom global-auto-revert-mode-hook nil
	155	"Hook called when Global Auto-Revert Mode is activated."
	156	:group 'auto-revert
	157	:type 'hook)
	158
	159	(defcustom global-auto-revert-non-file-buffers nil
	160	"*When nil only file buffers are reverted by Global Auto-Revert Mode.
	161
	162	When non-nil, both file buffers and buffers with a custom
	163	`revert-buffer-function' are reverted by Global Auto-Revert Mode."
	164	:group 'auto-revert
	165	:type 'boolean)
	166
	167	(defcustom global-auto-revert-non-file-buffers nil
	168	"When nil only file buffers are reverted by Global Auto-Revert Mode.
	169
	170	When non-nil, both file buffers and buffers with a custom
	171	`revert-buffer-function' are reverted by Global Auto-Revert Mode.
	172
	173	Use this option with care since it could lead to excessive reverts."
	174	:group 'auto-revert
	175	:type 'boolean)
	176
	177	(defcustom global-auto-revert-ignore-modes '()
	178	"List of major modes Global Auto-Revert Mode should not check."
	179	:group 'auto-revert
	180	:type '(repeat sexp))
	181
	182	(defcustom auto-revert-load-hook nil
	183	"Functions to run when Auto-Revert Mode is first loaded."
	184	:tag "Load Hook"
	185	:group 'auto-revert
	186	:type 'hook)
	187
	188	(defvar global-auto-revert-ignore-buffer nil
f1e3ff80	189	"*When non-nil, Global Auto-Revert Mode will not revert this buffer.
4a35aff3	190
48764ae2	191	This variable becomes buffer local when set in any fashion.")
4a35aff3 RS	192	(make-variable-buffer-local 'global-auto-revert-ignore-buffer)
	193
	194
	195	;; Internal variables:
	196
	197	(defvar auto-revert-buffer-list '()
	198	"List of buffers in Auto-Revert Mode.
	199
	200	Note that only Auto-Revert Mode, never Global Auto-Revert Mode, adds
	201	buffers to this list.
	202
	203	The timer function `auto-revert-buffers' is responsible for purging
	204	the list of old buffers.")
	205
	206	(defvar auto-revert-timer nil
	207	"Timer used by Auto-Revert Mode.")
	208
	209	(defvar auto-revert-remaining-buffers '()
	210	"Buffers not checked when user input stopped execution.")
	211
	212
	213	;; Functions:
	214
	215	;;;###autoload
	216	(defun auto-revert-mode (&optional arg)
48764ae2	217	"Toggle reverting buffer when file on disk changes.
4a35aff3	218
48764ae2 DL	219	With arg, turn Auto Revert mode on if and only if arg is positive.
48764ae2 DL	220	This is a minor mode that affects only the current buffer.
4a35aff3 RS	221	Use `global-auto-revert-mode' to automatically revert all buffers."
	222	(interactive "P")
	223	(make-local-variable 'auto-revert-mode)
afa95cac	224	(put 'auto-revert-mode 'permanent-local t)
4a35aff3 RS	225	(setq auto-revert-mode
	226	(if (null arg)
	227	(not auto-revert-mode)
	228	(> (prefix-numeric-value arg) 0)))
	229	(if (and auto-revert-verbose
	230	(interactive-p))
	231	(message "Auto-Revert Mode is now %s."
	232	(if auto-revert-mode "on" "off")))
	233	(if auto-revert-mode
	234	(if (not (memq (current-buffer) auto-revert-buffer-list))
	235	(push (current-buffer) auto-revert-buffer-list))
	236	(setq auto-revert-buffer-list
	237	(delq (current-buffer) auto-revert-buffer-list)))
	238	(auto-revert-set-timer)
	239	(when auto-revert-mode
	240	(auto-revert-buffers)
39d62e7a GM	241	(run-hooks 'auto-revert-mode-hook))
39d62e7a GM	242	auto-revert-mode)
4a35aff3 RS	243
	244
	245	;;;###autoload
	246	(defun turn-on-auto-revert-mode ()
	247	"Turn on Auto-Revert Mode.
	248
	249	This function is designed to be added to hooks, for example:
	250	(add-hook 'c-mode-hook 'turn-on-auto-revert-mode)"
	251	(auto-revert-mode 1))
	252
	253
	254	;;;###autoload
	255	(defun global-auto-revert-mode (&optional arg)
	256	"Revert any buffer when file on disk change.
	257
48764ae2 DL	258	With arg, turn Auto Revert mode on globally if and only if arg is positive.
48764ae2 DL	259	This is a minor mode that affects all buffers.
4a35aff3 RS	260	Use `auto-revert-mode' to revert a particular buffer."
	261	(interactive "P")
	262	(setq global-auto-revert-mode
	263	(if (null arg)
	264	(not global-auto-revert-mode)
	265	(> (prefix-numeric-value arg) 0)))
	266	(if (and auto-revert-verbose
	267	(interactive-p))
f1e3ff80	268	(message "Global Auto-Revert Mode is now %s."
4a35aff3 RS	269	(if global-auto-revert-mode "on" "off")))
	270	(auto-revert-set-timer)
	271	(when global-auto-revert-mode
	272	(auto-revert-buffers)
	273	(run-hooks 'global-auto-revert-mode-hook)))
	274
	275
	276	(defun auto-revert-set-timer ()
	277	"Restart or cancel the timer."
	278	(if (timerp auto-revert-timer)
	279	(cancel-timer auto-revert-timer))
	280	(if (or global-auto-revert-mode auto-revert-buffer-list)
	281	(setq auto-revert-timer (run-with-timer auto-revert-interval
	282	auto-revert-interval
	283	'auto-revert-buffers))
	284	(setq auto-revert-timer nil)))
	285
	286
	287	(defun auto-revert-buffers ()
	288	"Revert buffers as specified by Auto-Revert and Global Auto-Revert Mode.
	289
	290	Should `global-auto-revert-mode' be active all file buffers are checked.
	291
	292	Should `auto-revert-mode' be active in some buffers, those buffers
	293	are checked.
	294
	295	Non-file buffers that have a custom `revert-buffer-function' are
	296	reverted either when Auto-Revert Mode is active in that buffer, or
	297	when the variable `global-auto-revert-non-file-buffers' is non-nil
	298	and Global Auto-Revert Mode is active.
	299
48764ae2	300	This function stops whenever there is user input. The buffers not
4a35aff3 RS	301	checked are stored in the variable `auto-revert-remaining-buffers'.
	302
	303	To avoid starvation, the buffers in `auto-revert-remaining-buffers'
	304	are checked first the next time this function is called.
	305
48764ae2	306	This function is also responsible for removing buffers no longer in
4a35aff3 RS	307	Auto-Revert mode from `auto-revert-buffer-list', and for canceling
	308	the timer when no buffers need to be checked."
	309	(let ((bufs (if global-auto-revert-mode
	310	(buffer-list)
	311	auto-revert-buffer-list))
	312	(remaining '())
	313	(new '()))
	314	;; Partition `bufs' into two halves depending on whether or not
	315	;; the buffers are in `auto-revert-remaining-buffers'. The two
	316	;; halves are then re-joined with the "remaining" buffers at the
	317	;; head of the list.
	318	(dolist (buf auto-revert-remaining-buffers)
	319	(if (memq buf bufs)
	320	(push buf remaining)))
	321	(dolist (buf bufs)
	322	(if (not (memq buf remaining))
	323	(push buf new)))
	324	(setq bufs (nreverse (nconc new remaining)))
	325	(while (and bufs
	326	(not (and auto-revert-stop-on-user-input
	327	(input-pending-p))))
	328	(let ((buf (car bufs)))
	329	(if (buffer-name buf) ; Buffer still alive?
	330	(save-excursion
	331	(set-buffer buf)
	332	;; Test if someone has turned off Auto-Revert Mode in a
	333	;; non-standard way, for example by changing major mode.
	334	(if (and (not auto-revert-mode)
	335	(memq buf auto-revert-buffer-list))
	336	(setq auto-revert-buffer-list
	337	(delq buf auto-revert-buffer-list)))
	338	(when (and
	339	(or auto-revert-mode
	340	(and
	341	global-auto-revert-mode
	342	(not global-auto-revert-ignore-buffer)
	343	(not (memq major-mode
	344	global-auto-revert-ignore-modes))))
	345	(not (buffer-modified-p))
	346	(if (buffer-file-name)
	347	(and (file-readable-p (buffer-file-name))
	348	(not (verify-visited-file-modtime buf)))
	349	(and revert-buffer-function
	350	(or (and global-auto-revert-mode
	351	global-auto-revert-non-file-buffers)
	352	auto-revert-mode))))
	353	(if auto-revert-verbose
	354	(message "Reverting buffer `%s'." buf))
a468671a	355	(revert-buffer t t t)))
4a35aff3 RS	356	;; Remove dead buffer from `auto-revert-buffer-list'.
	357	(setq auto-revert-buffer-list
	358	(delq buf auto-revert-buffer-list))))
	359	(setq bufs (cdr bufs)))
	360	(setq auto-revert-remaining-buffers bufs)
	361	;; Check if we should cancel the timer.
	362	(when (and (not global-auto-revert-mode)
	363	(null auto-revert-buffer-list))
	364	(cancel-timer auto-revert-timer)
	365	(setq auto-revert-timer nil))))
	366
	367
	368	;; The end:
	369
	370	(unless (assq 'auto-revert-mode minor-mode-alist)
	371	(push '(auto-revert-mode auto-revert-mode-text)
	372	minor-mode-alist))
	373	(unless (assq 'global-auto-revert-mode minor-mode-alist)
	374	(push '(global-auto-revert-mode global-auto-revert-mode-text)
	375	minor-mode-alist))
	376
	377	(provide 'autorevert)
	378
	379	(run-hooks 'auto-revert-load-hook)
	380
	381	;; This makes it possible to set Global Auto-Revert Mode from
	382	;; Customize.
	383	(if global-auto-revert-mode
	384	(global-auto-revert-mode 1))
	385
	386	;; autorevert.el ends here.