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1 ;;; auto-save.el --- safer auto saving with support for ange-ftp and /tmp 1 ;; -*- Emacs-Lisp -*-
2 2 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
3 (defconst auto-save-version "cvs ate me") 3 ;;
4 4 ;; File: auto-save.el
5 ;;;; Copyright (C) 1992, 1993, 1994 by Sebastian Kremer <sk@thp.uni-koeln.de> 5 ;; Version: $Revision: 1.2 $
6 ;;;; Modified by jwz 6 ;; RCS:
7 7 ;; Description: Safer autosaving with support for efs and /tmp.
8 ;; This file is part of XEmacs. 8 ;; This version of auto-save is designed to work with efs,
9 9 ;; instead of ange-ftp.
10 ;; XEmacs is free software; you can redistribute it and/or modify it 10 ;; Author: Sebastian Kremer <sk@thp.uni-koeln.de>,
11 ;; under the terms of the GNU General Public License as published by 11 ;;
12 ;; the Free Software Foundation; either version 2, or (at your option) 12 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
13 ;; any later version. 13
14 14 (defconst auto-save-version (substring "$Revision: 1.2 $" 11 -2)
15 ;; XEmacs is distributed in the hope that it will be useful, but 15 "Version number of auto-save.")
16 ;; WITHOUT ANY WARRANTY; without even the implied warranty of 16
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 ;;; Copyright (C) 1992 by Sebastian Kremer <sk@thp.uni-koeln.de>
18 ;; General Public License for more details. 18
19 19 ;;; This program is free software; you can redistribute it and/or modify
20 ;; You should have received a copy of the GNU General Public License 20 ;;; it under the terms of the GNU General Public License as published by
21 ;; along with XEmacs; see the file COPYING. If not, write to the 21 ;;; the Free Software Foundation; either version 1, or (at your option)
22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330, 22 ;;; any later version.
23 ;; Boston, MA 02111-1307, USA. 23
24 24 ;;; This program is distributed in the hope that it will be useful,
25 ;;; Synched up with: Not in FSF. 25 ;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
26 26 ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
27 ;;;; LISPDIR ENTRY for the Elisp Archive =============================== 27 ;;; GNU General Public License for more details.
28 ;;;; LCD Archive Entry: 28
29 ;;;; auto-save|Sebastian Kremer|sk@thp.uni-koeln.de 29 ;;; You should have received a copy of the GNU General Public License
30 ;;;; |safer auto saving with support for ange-ftp and /tmp 30 ;;; along with this program; if not, write to the Free Software
31 ;;; Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
31 32
32 ;;;; OVERVIEW ========================================================== 33 ;;;; OVERVIEW ==========================================================
33 34
34 ;;;; Combines autosaving for ange-ftp (to a local or remote directory) 35 ;;; Combines autosaving for efs (to a local or remote directory)
35 ;;;; with the ability to do autosaves to a fixed directory on a local 36 ;;; with the ability to do autosaves to a fixed directory on a local
36 ;;;; disk, in case NFS is slow. The auto-save file used for 37 ;;; disk, in case NFS is slow. The auto-save file used for
37 ;;;; /usr/foo/bar/baz.txt 38 ;;; /usr/foo/bar/baz.txt
38 ;;;; will be 39 ;;; will be
39 ;;;; AUTOSAVE/#\!usr\!foo\!bar\!baz.txt# 40 ;;; AUTOSAVE/#\!usr\!foo\!bar\!baz.txt#
40 ;;;; assuming AUTOSAVE is the non-nil value of the variable 41 ;;; assuming AUTOSAVE is the non-nil value of the variable
41 ;;;; `auto-save-directory'. 42 ;;; `auto-save-directory'.
42 43
43 ;;;; Takes care that autosave files for non-file-buffers (e.g. *mail*) 44 ;;; Takes care that autosave files for non-file-buffers (e.g. *mail*)
44 ;;;; from two simultaneous Emacses don't collide. 45 ;;; from two simultaneous Emacses don't collide.
45 46
46 ;;;; Autosaves even if the current directory is not writable. 47 ;;; Autosaves even if the current directory is not writable.
47 48
48 ;;;; Can limit autosave names to 14 characters using a hash function, 49 ;;; Can limit autosave names to 14 characters using a hash function,
49 ;;;; see `auto-save-hash-p'. 50 ;;; see `auto-save-hash-p'.
50 51
51 ;;;; See `auto-save-directory' and `make-auto-save-file-name' and 52 ;;; See `auto-save-directory' and `make-auto-save-file-name' and
52 ;;;; references therein for complete documentation. 53 ;;; references therein for complete documentation.
53 54
54 ;;;; Meta-x recover-all-files will effectively do recover-file on all 55 ;;; Meta-x recover-all-files will effectively do recover-file on all
55 ;;;; files whose autosave file is newer (one of the benefits of having 56 ;;; files whose autosave file is newer (one of the benefits of having
56 ;;;; all autosave files in the same place). 57 ;;; all autosave files in the same place).
57 58
58 ;;;; INSTALLATION ====================================================== 59 ;;;; INSTALLATION ======================================================
59 60
60 ;;;; Put this file into your load-path and the following in your ~/.emacs: 61 ;;; Put this file into your load-path and the following in your ~/.emacs:
61 62
62 ;;;; If you want to autosave in the fixed directory /tmp/USER-autosave/ 63 ;;; If you want to autosave in the fixed directory /tmp/USER-autosave/
63 ;;;; (setq auto-save-directory 64 ;;; (setq auto-save-directory
64 ;;;; (concat "/tmp/" (user-login-name) "-autosave/")) 65 ;;; (concat "/tmp/" (user-login-name) "-autosave/"))
65 66
66 ;;;; If you don't want to save in /tmp (e.g., because it is swap 67 ;;; If you don't want to save in /tmp (e.g., because it is swap
67 ;;;; mounted) but rather in ~/autosave/ 68 ;;; mounted) but rather in ~/autosave/
68 ;;;; (setq auto-save-directory (expand-file-name "~/autosave/")) 69 ;;; (setq auto-save-directory (expand-file-name "~/autosave/"))
69 70
70 ;;;; If you want to save each file in its own directory (the default) 71 ;;; If you want to save each file in its own directory (the default)
71 ;;;; (setq auto-save-directory nil) 72 ;;; (setq auto-save-directory nil)
72 ;;;; You still can take advantage of autosaving ange-ftp remote files 73 ;;; You still can take advantage of autosaving efs remote files
73 ;;;; in a fixed local directory, `auto-save-directory-fallback' will 74 ;;; in a fixed local directory, `auto-save-directory-fallback' will
74 ;;;; be used. 75 ;;; be used.
75 76
76 ;;;; If you want to use 14 character hashed autosave filenames 77 ;;; If you want to use 14 character hashed autosave filenames
77 ;;;; (setq auto-save-hash-p t) 78 ;;; (setq auto-save-hash-p t)
78 79
79 ;;;; Finally, put this line after the others in your ~/.emacs: 80 ;;; Finally, put this line after the others in your ~/.emacs:
80 ;;;; (require 'auto-save) 81 ;;; (require 'auto-save)
81 82
82 83
83 ;;;; ACKNOWLEDGEMENT =================================================== 84 ;;;; ACKNOWLEDGEMENT ===================================================
84 85
85 ;;;; This code is loosely derived from autosave-in-tmp.el by Jamie 86 ;;; This code is loosely derived from autosave-in-tmp.el by Jamie
86 ;;;; Zawinski <jwz@lucid.com> (the version I had was last modified 22 87 ;;; Zawinski <jwz@lucid.com> (the version I had was last modified 22
87 ;;;; dec 90 jwz) and code submitted to ange-ftp-lovers on Sun, 5 Apr 88 ;;; dec 90 jwz) and code submitted to ange-ftp-lovers on Sun, 5 Apr
88 ;;;; 92 23:20:47 EDT by drw@BOURBAKI.MIT.EDU (Dale R. Worley). 89 ;;; 92 23:20:47 EDT by drw@BOURBAKI.MIT.EDU (Dale R. Worley).
89 ;;;; auto-save.el tries to cover the functionality of those two 90 ;;; auto-save.el tries to cover the functionality of those two
90 ;;;; packages. 91 ;;; packages.
91 92
92 ;;;; Valuable comments and help from Dale Worley, Andy Norman, Jamie 93 ;;; Valuable comments and help from Dale Worley, Andy Norman, Jamie
93 ;;;; Zawinski and Sandy Rutherford are gratefully acknowledged. 94 ;;; Zawinski and Sandy Rutherford are gratefully acknowledged.
95
96 ;;;; PROVISION ========================================================
97
98 (provide 'auto-save)
94 99
95 ;;;; CUSTOMIZATION ===================================================== 100 ;;;; CUSTOMIZATION =====================================================
96 101
97 (defvar auto-save-directory nil 102 (defvar auto-save-directory nil
98 103
117 The value \(expand-file-name \"~/autosave/\"\) might be better if /tmp 122 The value \(expand-file-name \"~/autosave/\"\) might be better if /tmp
118 is mounted from swap (possible in SunOS, type `df /tmp' to find out) 123 is mounted from swap (possible in SunOS, type `df /tmp' to find out)
119 and thus vanishes after a reboot, or if your system is particularly 124 and thus vanishes after a reboot, or if your system is particularly
120 thorough when cleaning up /tmp, clearing even non-empty subdirectories. 125 thorough when cleaning up /tmp, clearing even non-empty subdirectories.
121 126
122 It should never be an ange-ftp remote filename because that would 127 It should never be an efs remote filename because that would
123 defeat `ange-ftp-auto-save-remotely'. 128 defeat `efs-auto-save-remotely'.
124 129
125 Unless you set `auto-save-hash-p', you shouldn't set this to a 130 Unless you set `auto-save-hash-p', you shouldn't set this to a
126 directory in a filesystem that does not support long filenames, since 131 directory in a filesystem that does not support long filenames, since
127 a file named 132 a file named
128 133
132 137
133 AUTO-SAVE-DIRECTORY/#\\!home\\!sk\\!lib\\!emacs\\!lisp\\!auto-save.el# 138 AUTO-SAVE-DIRECTORY/#\\!home\\!sk\\!lib\\!emacs\\!lisp\\!auto-save.el#
134 139
135 as auto save file. 140 as auto save file.
136 141
137 See also variables `auto-save-directory-fallback', `auto-save-hash-p', 142 See also variables `auto-save-directory-fallback',
138 `ange-ftp-auto-save' and `ange-ftp-auto-save-remotely'.") 143 `efs-auto-save' and `efs-auto-save-remotely'.")
139 144
140 (defvar auto-save-hash-p nil 145 (defvar auto-save-hash-p nil
141 "If non-nil, hashed autosave names of length 14 are used. 146 "If non-nil, hashed autosave names of length 14 are used.
142 This is to avoid autosave filenames longer than 14 characters. 147 This is to avoid autosave filenames longer than 14 characters.
143 The directory used is `auto-save-hash-directory' regardless of 148 The directory used is `auto-save-hash-directory' regardless of
144 `auto-save-directory'. 149 `auto-save-directory'.
145 Hashing defeats `recover-all-files', you have to recover files 150 Hashing defeats `recover-all-files', you have to recover files
146 individually by doing `recover-file'.") 151 individually by doing `recover-file'.")
147 152
148 ;;; This defvar is in ange-ftp.el now, but for older versions it 153 ;;; This defvar is in efs.el now, but doesn't hurt to give it here as
149 ;;; doesn't hurt to give it here as well so that loading auto-save.el 154 ;;; well so that loading first auto-save.el does not abort.
150 ;;; does not abort. 155 (or (boundp 'efs-auto-save) (defvar efs-auto-save 0))
151 (defvar ange-ftp-auto-save 0 156 (or (boundp 'efs-auto-save-remotely) (defvar efs-auto-save-remotely nil))
152 "If 1, allows ange-ftp files to be auto-saved. 157
153 If 0, suppresses auto-saving of ange-ftp files. 158 (defvar auto-save-offer-delete nil
154 Don't use any other value.") 159 "*If non-nil, `recover-all-files' offers to delete autosave files
155 160 that are out of date or were dismissed for recovering.
156 (defvar ange-ftp-auto-save-remotely nil 161 Special value 'always deletes those files silently.")
157 "*If non-nil, causes the auto-save file for an ange-ftp file to be written in
158 the remote directory containing the file, rather than in a local directory.
159
160 For remote files, this being true overrides a non-nil
161 `auto-save-directory'. Local files are unaffected.
162
163 If you want to use this feature, you probably only want to set this
164 true in a few buffers, rather than globally. You might want to give
165 each buffer its own value using `make-variable-buffer-local'.
166
167 See also variable `ange-ftp-auto-save'.")
168 162
169 ;;;; end of customization 163 ;;;; end of customization
170 164
171 165
172 ;;; Preparations to be done at load time 166 ;;; Preparations to be done at load time
173 167
174 (defvar auto-save-directory-fallback (expand-file-name "~/autosave/") 168 (defvar auto-save-directory-fallback (expand-file-name "~/autosave/")
175 ;; not user-variable-p, see above 169 ;; not user-variable-p, see above
176 "Directory used for local autosaving of remote files if 170 "Directory used for local autosaving of remote files if
177 both `auto-save-directory' and `ange-ftp-auto-save-remotely' are nil. 171 both `auto-save-directory' and `efs-auto-save-remotely' are nil.
178 Also used if a working directory to be used for autosaving is not writable. 172 Also used if a working directory to be used for autosaving is not writable.
179 This *must* always be the name of directory that exists or can be 173 This *must* always be the name of directory that exists or can be
180 created by you, never nil.") 174 created by you, never nil.")
181 175
182 (defvar auto-save-hash-directory 176 (defvar auto-save-hash-directory
196 ;; Else we create and chmod 0700 the directory 190 ;; Else we create and chmod 0700 the directory
197 (setq dir (directory-file-name dir)) ; some systems need this 191 (setq dir (directory-file-name dir)) ; some systems need this
198 (if (fboundp 'make-directory) ; V19 or tree dired 192 (if (fboundp 'make-directory) ; V19 or tree dired
199 (make-directory dir) 193 (make-directory dir)
200 (call-process "mkdir" nil nil nil dir)) 194 (call-process "mkdir" nil nil nil dir))
201 ;; This is 1300, aka "d-wx-----T"
202 ;; The sticky bit means that you can only delete your own files,
203 ;; even if you have write permission in the directory (which is
204 ;; moot, since the directory is only writable by owner.)
205 (set-file-modes dir (* 7 8 8)))))) 195 (set-file-modes dir (* 7 8 8))))))
206 196
207 (mapcar (function auto-save-check-directory) 197 (mapcar (function auto-save-check-directory)
208 '(auto-save-directory auto-save-directory-fallback)) 198 '(auto-save-directory auto-save-directory-fallback))
209 199
222 212
223 Offers to autosave all files in the same `auto-save-directory'. All 213 Offers to autosave all files in the same `auto-save-directory'. All
224 autosave files can then be recovered at once with function 214 autosave files can then be recovered at once with function
225 `recover-all-files'. 215 `recover-all-files'.
226 216
227 Takes care to make autosave files for files accessed through ange-ftp 217 Takes care to make autosave files for files accessed through efs
228 be local files if variable `ange-ftp-auto-save-remotely' is nil. 218 be local files if variable `efs-auto-save-remotely' is nil.
229 219
230 Takes care of slashes in buffer names to prevent autosave errors. 220 Takes care of slashes in buffer names to prevent autosave errors.
221
222 Takes care that autosave files for buffers not visiting any file (such
223 as `*mail*') from two simultaneous Emacses don't collide by prepending
224 the Emacs pid.
231 225
232 Uses 14 character autosave names if `auto-save-hash-p' is true. 226 Uses 14 character autosave names if `auto-save-hash-p' is true.
233 227
234 Autosaves even if the current directory is not writable, using 228 Autosaves even if the current directory is not writable, using
235 directory `auto-save-directory-fallback'. 229 directory `auto-save-directory-fallback'.
240 ;; We have to be very careful about not signalling an error in this 234 ;; We have to be very careful about not signalling an error in this
241 ;; function since files.el does not provide for this (e.g. find-file 235 ;; function since files.el does not provide for this (e.g. find-file
242 ;; would fail for each new file). 236 ;; would fail for each new file).
243 237
244 (condition-case error-data 238 (condition-case error-data
245 (let* ((file-name (or (and (boundp 'buffer-file-truename) ; From jwz, 239 (let* ((file-name (or (and (boundp 'buffer-file-truename)
246 buffer-file-truename) ; for Emacs 19? 240 buffer-file-truename
247 buffer-file-name)) 241 ;; Make sure that the file name is expanded.
242 (expand-file-name buffer-file-name))
243 (and buffer-file-name
244 (expand-file-name buffer-file-name))))
248 ;; So autosavename looks like #%...#, roughly as with the 245 ;; So autosavename looks like #%...#, roughly as with the
249 ;; old make-auto-save-file-name function. The 246 ;; old make-auto-save-file-name function. The
250 ;; make-temp-name inserts the pid of this Emacs: this 247 ;; make-temp-name inserts the pid of this Emacs: this
251 ;; avoids autosaving from two Emacses into the same file. 248 ;; avoids autosaving from two Emacses into the same file.
252 ;; It cannot be recovered automatically then because in 249 ;; It cannot be recovered automatically then because in
253 ;; the next Emacs session (the one after the crash) the 250 ;; the next Emacs session (the one after the crash) the
254 ;; pid will be different, but file-less buffers like 251 ;; pid will be different, but file-less buffers like
255 ;; *mail* must be recovered manually anyway. 252 ;; *mail* must be recovered manually anyway.
256 253 (name-prefix (if file-name nil (make-temp-name "#%")))
257 ;; jwz: putting the emacs PID in the auto-save file name is bad
258 ;; news, because that defeats auto-save-recovery of *mail*
259 ;; buffers -- the (sensible) code in sendmail.el calls
260 ;; (make-auto-save-file-name) to determine whether there is
261 ;; unsent, auto-saved mail to recover. If that mail came from a
262 ;; previous emacs process (far and away the most likely case)
263 ;; then this can never succeed as the pid differs.
264 ;; (name-prefix (if file-name nil (make-temp-name "#%")))
265 (name-prefix (if file-name nil "#%"))
266
267 (save-name (or file-name 254 (save-name (or file-name
268 ;; Prevent autosave errors. Buffername 255 ;; Prevent autosave errors. Buffername
269 ;; (to become non-dir part of filename) will 256 ;; (to become non-dir part of filename) will
270 ;; be unslashified twice. Don't care. 257 ;; be unslashified twice. Don't care.
271 (auto-save-unslashify-name (buffer-name)))) 258 (auto-save-unslashify-name (buffer-name))))
272 (remote-p (and (stringp file-name) 259 (remote-p (and (stringp file-name)
273 (fboundp 'ange-ftp-ftp-path) 260 (fboundp 'efs-ftp-path)
274 (ange-ftp-ftp-path file-name)))) 261 (efs-ftp-path file-name))))
275 ;; Return the appropriate auto save file name: 262 ;; Return the appropriate auto save file name:
276 (expand-file-name;; a buffername needs this, a filename not 263 (expand-file-name;; a buffername needs this, a filename not
277 (if remote-p 264 (if remote-p
278 (if ange-ftp-auto-save-remotely 265 (if efs-auto-save-remotely
279 (auto-save-name-in-same-directory save-name) 266 (auto-save-name-in-same-directory save-name)
280 ;; We have to use the `fixed-directory' now since the 267 ;; We have to use the `fixed-directory' now since the
281 ;; `same-directory' would be remote. 268 ;; `same-directory' would be remote.
282 ;; It will use the fallback if needed. 269 ;; It will use the fallback if needed.
283 (auto-save-name-in-fixed-directory save-name)) 270 (auto-save-name-in-fixed-directory save-name))
284 ;; Else it is a local file (or a buffer without a file, hence 271 ;; Else it is a local file (or a buffer without a file, hence
285 ;; the name-prefix). 272 ;; the name-prefix).
286 ;; Hashed files always go into the special hash dir, never 273 ;; Hashed files always go into the special hash dir, never
287 ;; in the same directory, to make recognizing reliable. 274 ;; in the same directory, to make recognizing reliable.
288 (if (or auto-save-directory auto-save-hash-p) 275 (if (or auto-save-directory auto-save-hash-p)
289 (auto-save-name-in-fixed-directory save-name name-prefix) 276 (auto-save-name-in-fixed-directory save-name name-prefix)
290 (auto-save-name-in-same-directory save-name name-prefix))))) 277 (auto-save-name-in-same-directory save-name name-prefix)))))
291 278
292 ;; If any error occurs in the above code, return what the old 279 ;; If any error occurs in the above code, return what the old
293 ;; version of this function would have done. It is not ok to 280 ;; version of this function would have done. It is not ok to
294 ;; return nil, e.g., when after-find-file tests 281 ;; return nil, e.g., when after-find-file tests
295 ;; file-newer-than-file-p, nil would bomb. 282 ;; file-newer-than-file-p, nil would bomb.
296 283
394 ;;; Hashing function contributed by Andy Norman <ange@hplb.hpl.hp.com> 381 ;;; Hashing function contributed by Andy Norman <ange@hplb.hpl.hp.com>
395 ;;; based upon C code from pot@fly.cnuce.cnr.IT (Francesco Potorti`). 382 ;;; based upon C code from pot@fly.cnuce.cnr.IT (Francesco Potorti`).
396 383
397 (defun auto-save-cyclic-hash-14 (s) 384 (defun auto-save-cyclic-hash-14 (s)
398 ;; "Hash string S into a string of length 14. 385 ;; "Hash string S into a string of length 14.
386 ;; A 7-bytes cyclic code for burst correction is calculated on a
387 ;; byte-by-byte basis. The polynomial used is D^7 + D^6 + D^3 +1.
399 ;; The resulting string consists of hexadecimal digits [0-9a-f]. 388 ;; The resulting string consists of hexadecimal digits [0-9a-f].
400 ;; In particular, it contains no slash, so it can be used as autosave name." 389 ;; In particular, it contains no slash, so it can be used as autosave name."
401 (let ((crc (make-string 8 0)) 390 (let ((crc (make-string 7 0))
402 result) 391 result)
403 (mapcar 392 (mapcar
404 (function 393 (function
405 (lambda (new) 394 (lambda (new)
406 (setq new (+ new (aref crc 7))) 395 (setq new (+ new (aref crc 6)))
407 (aset crc 7 (aref crc 6))
408 (aset crc 6 (+ (aref crc 5) new)) 396 (aset crc 6 (+ (aref crc 5) new))
409 (aset crc 5 (aref crc 4)) 397 (aset crc 5 (aref crc 4))
410 (aset crc 4 (aref crc 3)) 398 (aset crc 4 (aref crc 3))
411 (aset crc 3 (+ (aref crc 2) new)) 399 (aset crc 3 (+ (aref crc 2) new))
412 (aset crc 2 (aref crc 1)) 400 (aset crc 2 (aref crc 1))
418 (aref crc 1) 406 (aref crc 1)
419 (aref crc 2) 407 (aref crc 2)
420 (aref crc 3) 408 (aref crc 3)
421 (aref crc 4) 409 (aref crc 4)
422 (aref crc 5) 410 (aref crc 5)
423 (aref crc 6) 411 (aref crc 6)))
424 (aref crc 7)))
425 result)) 412 result))
426 413
414 ;; This leaves two characters that could be used to wrap it in `#' or
415 ;; make two filenames from it: one for autosaving, and another for a
416 ;; file containing the name of the autosaved filed, to make hashing
417 ;; reversible.
418 (defun auto-save-cyclic-hash-12 (s)
419 "Outputs the 12-characters ascii hex representation of a 6-bytes
420 cyclic code for burst correction calculated on STRING on a
421 byte-by-byte basis. The used polynomial is D^6 + D^5 + D^4 + D^3 +1."
422 (let ((crc (make-string 6 0)))
423 (mapcar
424 (function
425 (lambda (new)
426 (setq new (+ new (aref crc 5)))
427 (aset crc 5 (+ (aref crc 4) new))
428 (aset crc 4 (+ (aref crc 3) new))
429 (aset crc 3 (+ (aref crc 2) new))
430 (aset crc 2 (aref crc 1))
431 (aset crc 1 (aref crc 0))
432 (aset crc 0 new)))
433 s)
434 (format "%02x%02x%02x%02x%02x%02x"
435 (aref crc 0)
436 (aref crc 1)
437 (aref crc 2)
438 (aref crc 3)
439 (aref crc 4)
440 (aref crc 5))))
441
427 442
428 443
429 ;;; Recovering files 444 ;;; Recovering files
430 445
431 ;; jwz: changed this to also offer to recover auto-saved buffers which 446 (defun recover-all-files (&optional silent)
432 ;; had no associated file name (such as sendmail buffers.)
433 (defun recover-all-files ()
434 "Do recover-file for all autosave files which are current. 447 "Do recover-file for all autosave files which are current.
435 Only works if you have a non-nil `auto-save-directory'. 448 Only works if you have a non-nil `auto-save-directory'.
449
450 Optional prefix argument SILENT means to be silent about non-current
451 autosave files. This is useful if invoked automatically at Emacs
452 startup.
453
454 If `auto-save-offer-delete' is t, this function will offer to delete
455 old or rejected autosave files.
456
436 Hashed files (see `auto-save-hash-p') are not understood, use 457 Hashed files (see `auto-save-hash-p') are not understood, use
437 `recover-file' to recover them individually." 458 `recover-file' to recover them individually."
438 (interactive) 459 (interactive "P")
439 (let ((savefiles (directory-files auto-save-directory t "^#")) 460 (let ((savefiles (directory-files auto-save-directory t "^#"))
440 afile ; the auto save file 461 afile ; the auto save file
441 file ; its original file 462 file ; its original file
442 (total 0) ; # of files offered to recover 463 (total 0) ; # of files offered to recover
443 (count 0)) ; # of files actually recovered 464 (count 0)) ; # of files actually recovered
453 (message "autosave file \"%s\" is not current." afile) 474 (message "autosave file \"%s\" is not current." afile)
454 (sit-for 2)) 475 (sit-for 2))
455 (t 476 (t
456 (setq total (1+ total)) 477 (setq total (1+ total))
457 (with-output-to-temp-buffer "*Directory*" 478 (with-output-to-temp-buffer "*Directory*"
458 (apply 'call-process "ls" nil standard-output nil 479 (call-process "ls" nil standard-output nil
459 "-l" afile (if file (list file)))) 480 "-l" afile (if file (list file))))
460 (if (yes-or-no-p (format "Recover %s from auto save file? " 481 (if (yes-or-no-p (format "Recover %s from auto save file? "
461 (or file "non-file buffer"))) 482 file))
462 (let* ((obuf (current-buffer)) 483 (let* ((obuf (current-buffer))
463 (buf (set-buffer 484 (buf (set-buffer
464 (if file 485 (if file
465 (find-file-noselect file t) 486 (find-file-noselect file t)
466 (generate-new-buffer "*recovered*")))) 487 (generate-new-buffer "*recovered*"))))
474 (setq count (1+ count)) 495 (setq count (1+ count))
475 (message "\ 496 (message "\
476 Auto-save off in buffer \"%s\" till you do M-x auto-save-mode." 497 Auto-save off in buffer \"%s\" till you do M-x auto-save-mode."
477 (buffer-name)) 498 (buffer-name))
478 (set-buffer obuf) 499 (set-buffer obuf)
479 (sit-for 1)))))) 500 (sit-for 1))
501 ;; If not used for recovering, offer to delete
502 ;; autosave file
503 (and auto-save-offer-delete
504 (or (eq 'always auto-save-offer-delete)
505 (yes-or-no-p
506 (format "Delete autosave file for `%s'? " file)))
507 (delete-file afile))))))
480 (if (zerop total) 508 (if (zerop total)
481 (message "Nothing to recover.") 509 (or silent (message "Nothing to recover."))
482 (message "%d/%d file%s recovered." count total (if (= count 1) "" "s")))) 510 (message "%d/%d file%s recovered." count total (if (= count 1) "" "s"))))
483 (if (get-buffer "*Directory*") (kill-buffer "*Directory*"))) 511 (if (get-buffer "*Directory*") (kill-buffer "*Directory*")))
484 512
485 (provide 'auto-save) 513 ;;; end of auto-save.el