1 ;;; tar-mode.el --- simple editing of tar files from GNU emacs
3 ;; Copyright (C) 1990, 1991, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4 ;; 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
6 ;; Author: Jamie Zawinski <jwz@lucid.com>
8 ;; Created: 04 Apr 1990
11 ;; This file is part of GNU Emacs.
13 ;; GNU Emacs is free software; you can redistribute it and/or modify
14 ;; it under the terms of the GNU General Public License as published by
15 ;; the Free Software Foundation; either version 2, or (at your option)
18 ;; GNU Emacs is distributed in the hope that it will be useful,
19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 ;; GNU General Public License for more details.
23 ;; You should have received a copy of the GNU General Public License
24 ;; along with GNU Emacs; see the file COPYING. If not, write to the
25 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
26 ;; Boston, MA 02110-1301, USA.
30 ;; This package attempts to make dealing with Unix 'tar' archives easier.
31 ;; When this code is loaded, visiting a file whose name ends in '.tar' will
32 ;; cause the contents of that archive file to be displayed in a Dired-like
33 ;; listing. It is then possible to use the customary Dired keybindings to
34 ;; extract sub-files from that archive, either by reading them into their own
35 ;; editor buffers, or by copying them directly to arbitrary files on disk.
36 ;; It is also possible to delete sub-files from within the tar file and write
37 ;; the modified archive back to disk, or to edit sub-files within the archive
38 ;; and re-insert the modified files into the archive. See the documentation
39 ;; string of tar-mode for more info.
41 ;; This code now understands the extra fields that GNU tar adds to tar files.
43 ;; This interacts correctly with "uncompress.el" in the Emacs library,
46 ;; (autoload 'uncompress-while-visiting "uncompress")
47 ;; (setq auto-mode-alist (cons '("\\.Z$" . uncompress-while-visiting)
50 ;; Do not attempt to use tar-mode.el with crypt.el, you will lose.
52 ;; *************** TO DO ***************
54 ;; o chmod should understand "a+x,og-w".
56 ;; o It's not possible to add a NEW file to a tar archive; not that
57 ;; important, but still...
59 ;; o The code is less efficient that it could be - in a lot of places, I
60 ;; pull a 512-character string out of the buffer and parse it, when I could
61 ;; be parsing it in place, not garbaging a string. Should redo that.
63 ;; o I'd like a command that searches for a string/regexp in every subfile
64 ;; of an archive, where <esc> would leave you in a subfile-edit buffer.
65 ;; (Like the Meta-R command of the Zmacs mail reader.)
67 ;; o Sometimes (but not always) reverting the tar-file buffer does not
68 ;; re-grind the listing, and you are staring at the binary tar data.
69 ;; Typing 'g' again immediately after that will always revert and re-grind
70 ;; it, though. I have no idea why this happens.
72 ;; o Tar-mode interacts poorly with crypt.el and zcat.el because the tar
73 ;; write-file-hook actually writes the file. Instead it should remove the
74 ;; header (and conspire to put it back afterwards) so that other write-file
75 ;; hooks which frob the buffer have a chance to do their dirty work. There
76 ;; might be a problem if the tar write-file-hook does not come *first* on
79 ;; o Block files, sparse files, continuation files, and the various header
80 ;; types aren't editable. Actually I don't know that they work at all.
84 ;; Why does tar-mode edit the file itself instead of using tar?
86 ;; That means that you can edit tar files which you don't have room for
87 ;; on your local disk.
89 ;; I don't know about recent features in gnu tar, but old versions of tar
90 ;; can't replace a file in the middle of a tar file with a new version.
91 ;; Tar-mode can. I don't think tar can do things like chmod the subfiles.
92 ;; An implementation which involved unpacking and repacking the file into
93 ;; some scratch directory would be very wasteful, and wouldn't be able to
94 ;; preserve the file owners.
99 "Simple editing of tar files."
103 (defcustom tar-anal-blocksize 20
104 "The blocksize of tar files written by Emacs, or nil, meaning don't care.
105 The blocksize of a tar file is not really the size of the blocks; rather, it is
106 the number of blocks written with one system call. When tarring to a tape,
107 this is the size of the *tape* blocks, but when writing to a file, it doesn't
108 matter much. The only noticeable difference is that if a tar file does not
109 have a blocksize of 20, tar will tell you that; all this really controls is
110 how many null padding bytes go on the end of the tar file."
111 :type '(choice integer (const nil))
114 (defcustom tar-update-datestamp nil
115 "Non-nil means Tar mode should play fast and loose with sub-file datestamps.
116 If this is true, then editing and saving a tar file entry back into its
117 tar file will update its datestamp. If false, the datestamp is unchanged.
118 You may or may not want this - it is good in that you can tell when a file
119 in a tar archive has been changed, but it is bad for the same reason that
120 editing a file in the tar archive at all is bad - the changed version of
121 the file never exists on disk."
125 (defcustom tar-mode-show-date nil
126 "Non-nil means Tar mode should show the date/time of each subfile.
127 This information is useful, but it takes screen space away from file names."
131 (defvar tar-parse-info nil)
132 ;; Be sure that this variable holds byte position, not char position.
133 (defvar tar-header-offset nil)
134 (defvar tar-superior-buffer nil)
135 (defvar tar-superior-descriptor nil)
136 (defvar tar-subfile-mode nil)
138 (put 'tar-parse-info 'permanent-local t)
139 (put 'tar-header-offset 'permanent-local t)
140 (put 'tar-superior-buffer 'permanent-local t)
141 (put 'tar-superior-descriptor 'permanent-local t)
143 (defmacro tar-setf (form val)
144 "A mind-numbingly simple implementation of setf."
145 (let ((mform (macroexpand form (and (boundp 'byte-compile-macro-environment)
146 byte-compile-macro-environment))))
147 (cond ((symbolp mform) (list 'setq mform val))
148 ((not (consp mform)) (error "can't setf %s" form))
149 ((eq (car mform) 'aref)
150 (list 'aset (nth 1 mform) (nth 2 mform) val))
151 ((eq (car mform) 'car)
152 (list 'setcar (nth 1 mform) val))
153 ((eq (car mform) 'cdr)
154 (list 'setcdr (nth 1 mform) val))
155 (t (error "don't know how to setf %s" form)))))
157 ;;; down to business.
159 (defmacro make-tar-header (name mode uid git size date ck lt ln
160 magic uname gname devmaj devmin)
161 (list 'vector name mode uid git size date ck lt ln
162 magic uname gname devmaj devmin))
164 (defmacro tar-header-name (x) (list 'aref x 0))
165 (defmacro tar-header-mode (x) (list 'aref x 1))
166 (defmacro tar-header-uid (x) (list 'aref x 2))
167 (defmacro tar-header-gid (x) (list 'aref x 3))
168 (defmacro tar-header-size (x) (list 'aref x 4))
169 (defmacro tar-header-date (x) (list 'aref x 5))
170 (defmacro tar-header-checksum (x) (list 'aref x 6))
171 (defmacro tar-header-link-type (x) (list 'aref x 7))
172 (defmacro tar-header-link-name (x) (list 'aref x 8))
173 (defmacro tar-header-magic (x) (list 'aref x 9))
174 (defmacro tar-header-uname (x) (list 'aref x 10))
175 (defmacro tar-header-gname (x) (list 'aref x 11))
176 (defmacro tar-header-dmaj (x) (list 'aref x 12))
177 (defmacro tar-header-dmin (x) (list 'aref x 13))
179 (defmacro make-tar-desc (data-start tokens)
180 (list 'cons data-start tokens))
182 (defmacro tar-desc-data-start (x) (list 'car x))
183 (defmacro tar-desc-tokens (x) (list 'cdr x))
185 (defconst tar-name-offset 0)
186 (defconst tar-mode-offset (+ tar-name-offset 100))
187 (defconst tar-uid-offset (+ tar-mode-offset 8))
188 (defconst tar-gid-offset (+ tar-uid-offset 8))
189 (defconst tar-size-offset (+ tar-gid-offset 8))
190 (defconst tar-time-offset (+ tar-size-offset 12))
191 (defconst tar-chk-offset (+ tar-time-offset 12))
192 (defconst tar-linkp-offset (+ tar-chk-offset 8))
193 (defconst tar-link-offset (+ tar-linkp-offset 1))
194 ;;; GNU-tar specific slots.
195 (defconst tar-magic-offset (+ tar-link-offset 100))
196 (defconst tar-uname-offset (+ tar-magic-offset 8))
197 (defconst tar-gname-offset (+ tar-uname-offset 32))
198 (defconst tar-dmaj-offset (+ tar-gname-offset 32))
199 (defconst tar-dmin-offset (+ tar-dmaj-offset 8))
200 (defconst tar-end-offset (+ tar-dmin-offset 8))
202 (defun tar-header-block-tokenize (string)
203 "Return a `tar-header' structure.
204 This is a list of name, mode, uid, gid, size,
205 write-date, checksum, link-type, and link-name."
206 (cond ((< (length string) 512) nil)
207 (;(some 'plusp string) ; <-- oops, massive cycle hog!
208 (or (not (= 0 (aref string 0))) ; This will do.
209 (not (= 0 (aref string 101))))
210 (let* ((name-end (1- tar-mode-offset))
211 (link-end (1- tar-magic-offset))
212 (uname-end (1- tar-gname-offset))
213 (gname-end (1- tar-dmaj-offset))
214 (link-p (aref string tar-linkp-offset))
215 (magic-str (substring string tar-magic-offset (1- tar-uname-offset)))
216 (uname-valid-p (or (string= "ustar " magic-str) (string= "GNUtar " magic-str)))
218 (nulsexp "[^\000]*\000"))
219 (when (string-match nulsexp string tar-name-offset)
220 (setq name-end (min name-end (1- (match-end 0)))))
221 (when (string-match nulsexp string tar-link-offset)
222 (setq link-end (min link-end (1- (match-end 0)))))
223 (when (string-match nulsexp string tar-uname-offset)
224 (setq uname-end (min uname-end (1- (match-end 0)))))
225 (when (string-match nulsexp string tar-gname-offset)
226 (setq gname-end (min gname-end (1- (match-end 0)))))
227 (setq name (substring string tar-name-offset name-end)
228 link-p (if (or (= link-p 0) (= link-p ?0))
231 (setq linkname (substring string tar-link-offset link-end))
232 (if default-enable-multibyte-characters
234 (decode-coding-string name
235 (or file-name-coding-system
236 default-file-name-coding-system
239 (decode-coding-string linkname
240 (or file-name-coding-system
241 default-file-name-coding-system
243 (if (and (null link-p) (string-match "/\\'" name)) (setq link-p 5)) ; directory
246 (tar-parse-octal-integer string tar-mode-offset tar-uid-offset)
247 (tar-parse-octal-integer string tar-uid-offset tar-gid-offset)
248 (tar-parse-octal-integer string tar-gid-offset tar-size-offset)
249 (tar-parse-octal-integer string tar-size-offset tar-time-offset)
250 (tar-parse-octal-long-integer string tar-time-offset tar-chk-offset)
251 (tar-parse-octal-integer string tar-chk-offset tar-linkp-offset)
255 (and uname-valid-p (substring string tar-uname-offset uname-end))
256 (and uname-valid-p (substring string tar-gname-offset gname-end))
257 (tar-parse-octal-integer string tar-dmaj-offset tar-dmin-offset)
258 (tar-parse-octal-integer string tar-dmin-offset tar-end-offset)
260 (t 'empty-tar-block)))
263 (defun tar-parse-octal-integer (string &optional start end)
264 (if (null start) (setq start 0))
265 (if (null end) (setq end (length string)))
266 (if (= (aref string start) 0)
270 (setq n (if (< (aref string start) ?0) n
271 (+ (* n 8) (- (aref string start) ?0)))
275 (defun tar-parse-octal-long-integer (string &optional start end)
276 (if (null start) (setq start 0))
277 (if (null end) (setq end (length string)))
278 (if (= (aref string start) 0)
283 (if (>= (aref string start) ?0)
284 (setq lo (+ (* lo 8) (- (aref string start) ?0))
285 hi (+ (* hi 8) (ash lo -16))
286 lo (logand lo 65535)))
287 (setq start (1+ start)))
290 (defun tar-parse-octal-integer-safe (string)
291 (if (zerop (length string)) (error "empty string"))
293 (if (or (< c ?0) (> c ?7))
294 (error "`%c' is not an octal digit" c)))
296 (tar-parse-octal-integer string))
299 (defun tar-header-block-checksum (string)
300 "Compute and return a tar-acceptable checksum for this block."
301 (let* ((chk-field-start tar-chk-offset)
302 (chk-field-end (+ chk-field-start 8))
305 ;; Add up all of the characters except the ones in the checksum field.
306 ;; Add that field as if it were filled with spaces.
307 (while (< i chk-field-start)
308 (setq sum (+ sum (aref string i))
310 (setq i chk-field-end)
312 (setq sum (+ sum (aref string i))
316 (defun tar-header-block-check-checksum (hblock desired-checksum file-name)
317 "Beep and print a warning if the checksum doesn't match."
318 (if (not (= desired-checksum (tar-header-block-checksum hblock)))
319 (progn (beep) (message "Invalid checksum for file %s!" file-name))))
321 (defun tar-clip-time-string (time)
322 (let ((str (current-time-string time)))
323 (concat " " (substring str 4 16) (substring str 19 24))))
325 (defun tar-grind-file-mode (mode)
326 "Construct a `-rw--r--r--' string indicating MODE.
327 MODE should be an integer which is a file mode value."
329 (if (zerop (logand 256 mode)) ?- ?r)
330 (if (zerop (logand 128 mode)) ?- ?w)
331 (if (zerop (logand 1024 mode)) (if (zerop (logand 64 mode)) ?- ?x) ?s)
332 (if (zerop (logand 32 mode)) ?- ?r)
333 (if (zerop (logand 16 mode)) ?- ?w)
334 (if (zerop (logand 2048 mode)) (if (zerop (logand 8 mode)) ?- ?x) ?s)
335 (if (zerop (logand 4 mode)) ?- ?r)
336 (if (zerop (logand 2 mode)) ?- ?w)
337 (if (zerop (logand 1 mode)) ?- ?x)))
339 (defun tar-header-block-summarize (tar-hblock &optional mod-p)
340 "Return a line similar to the output of `tar -vtf'."
341 (let ((name (tar-header-name tar-hblock))
342 (mode (tar-header-mode tar-hblock))
343 (uid (tar-header-uid tar-hblock))
344 (gid (tar-header-gid tar-hblock))
345 (uname (tar-header-uname tar-hblock))
346 (gname (tar-header-gname tar-hblock))
347 (size (tar-header-size tar-hblock))
348 (time (tar-header-date tar-hblock))
349 ;; (ck (tar-header-checksum tar-hblock))
350 (type (tar-header-link-type tar-hblock))
351 (link-name (tar-header-link-name tar-hblock)))
352 (format "%c%c%s%8s/%-8s%7s%s %s%s"
354 (cond ((or (eq type nil) (eq type 0)) ?-)
355 ((eq type 1) ?h) ; link
356 ((eq type 2) ?l) ; symlink
357 ((eq type 3) ?c) ; char special
358 ((eq type 4) ?b) ; block special
359 ((eq type 5) ?d) ; directory
360 ((eq type 6) ?p) ; FIFO/pipe
361 ((eq type 20) ?*) ; directory listing
362 ((eq type 28) ?L) ; next has longname
363 ((eq type 29) ?M) ; multivolume continuation
364 ((eq type 35) ?S) ; sparse
365 ((eq type 38) ?V) ; volume header
368 (tar-grind-file-mode mode)
369 (if (= 0 (length uname)) uid uname)
370 (if (= 0 (length gname)) gid gname)
372 (if tar-mode-show-date (tar-clip-time-string time) "")
374 'mouse-face 'highlight
375 'help-echo "mouse-2: extract this file into a buffer")
376 (if (or (eq type 1) (eq type 2))
377 (concat (if (= type 1) " ==> " " --> ") link-name)
380 (defun tar-untar-buffer ()
381 "Extract all archive members in the tar-file into the current directory."
383 (let ((multibyte enable-multibyte-characters))
387 (set-buffer-multibyte nil)
388 (dolist (descriptor tar-parse-info)
389 (let* ((tokens (tar-desc-tokens descriptor))
390 (name (tar-header-name tokens))
391 (dir (file-name-directory name))
392 (start (+ (tar-desc-data-start descriptor)
393 (- tar-header-offset (point-min))))
394 (end (+ start (tar-header-size tokens))))
395 (unless (file-directory-p name)
396 (message "Extracting %s" name)
397 (if (and dir (not (file-exists-p dir)))
398 (make-directory dir t))
399 (unless (file-directory-p name)
400 (write-region start end name))
401 (set-file-modes name (tar-header-mode tokens))))))
402 (set-buffer-multibyte multibyte))))
404 (defun tar-summarize-buffer ()
405 "Parse the contents of the tar file in the current buffer.
406 Place a dired-like listing on the front;
407 then narrow to it, so that only that listing
408 is visible (and the real data of the buffer is hidden)."
409 (let ((modified (buffer-modified-p)))
410 (set-buffer-multibyte nil)
414 (make-progress-reporter "Parsing tar file..."
415 (point-min) (max 1 (- (buffer-size) 1024))))
417 (while (and (<= (+ pos 512) (point-max))
418 (not (eq 'empty-tar-block
420 (tar-header-block-tokenize
421 (buffer-substring pos (+ pos 512)))))))
422 (setq pos (+ pos 512))
423 (progress-reporter-update progress-reporter pos)
424 (if (eq (tar-header-link-type tokens) 20)
425 ;; Foo. There's an extra empty block after these.
426 (setq pos (+ pos 512)))
427 (let ((size (tar-header-size tokens)))
429 (error "%s has size %s - corrupted"
430 (tar-header-name tokens) size))
432 ; This is just too slow. Don't really need it anyway....
433 ;(tar-header-block-check-checksum
434 ; hblock (tar-header-block-checksum hblock)
435 ; (tar-header-name tokens))
437 (push (make-tar-desc pos tokens) result)
439 (and (null (tar-header-link-type tokens))
442 (+ pos 512 (ash (ash (1- size) -9) 9)) ; this works
443 ;(+ pos (+ size (- 512 (rem (1- size) 512)))) ; this doesn't
445 (make-local-variable 'tar-parse-info)
446 (setq tar-parse-info (nreverse result))
447 ;; A tar file should end with a block or two of nulls,
448 ;; but let's not get a fatal error if it doesn't.
449 (if (eq tokens 'empty-tar-block)
450 (progress-reporter-done progress-reporter)
451 (message "Warning: premature EOF parsing tar file")))
452 (set-buffer-multibyte default-enable-multibyte-characters)
453 (goto-char (point-min))
454 (let ((inhibit-read-only t))
455 ;; Collect summary lines and insert them all at once since tar files
456 ;; can be pretty big.
457 (let ((total-summaries
460 (tar-header-block-summarize (tar-desc-tokens tar-desc)))
463 (insert total-summaries "\n"))
464 (narrow-to-region (point-min) (point))
465 (set (make-local-variable 'tar-header-offset) (position-bytes (point)))
466 (goto-char (point-min))
467 (restore-buffer-modified-p modified))))
470 (let ((map (make-keymap)))
471 (suppress-keymap map)
472 (define-key map " " 'tar-next-line)
473 (define-key map "C" 'tar-copy)
474 (define-key map "d" 'tar-flag-deleted)
475 (define-key map "\^D" 'tar-flag-deleted)
476 (define-key map "e" 'tar-extract)
477 (define-key map "f" 'tar-extract)
478 (define-key map "\C-m" 'tar-extract)
479 (define-key map [mouse-2] 'tar-mouse-extract)
480 (define-key map "g" 'revert-buffer)
481 (define-key map "h" 'describe-mode)
482 (define-key map "n" 'tar-next-line)
483 (define-key map "\^N" 'tar-next-line)
484 (define-key map [down] 'tar-next-line)
485 (define-key map "o" 'tar-extract-other-window)
486 (define-key map "p" 'tar-previous-line)
487 (define-key map "q" 'quit-window)
488 (define-key map "\^P" 'tar-previous-line)
489 (define-key map [up] 'tar-previous-line)
490 (define-key map "R" 'tar-rename-entry)
491 (define-key map "u" 'tar-unflag)
492 (define-key map "v" 'tar-view)
493 (define-key map "x" 'tar-expunge)
494 (define-key map "\177" 'tar-unflag-backwards)
495 (define-key map "E" 'tar-extract-other-window)
496 (define-key map "M" 'tar-chmod-entry)
497 (define-key map "G" 'tar-chgrp-entry)
498 (define-key map "O" 'tar-chown-entry)
500 ;; Make menu bar items.
502 ;; Get rid of the Edit menu bar item to save space.
503 (define-key map [menu-bar edit] 'undefined)
505 (define-key map [menu-bar immediate]
506 (cons "Immediate" (make-sparse-keymap "Immediate")))
508 (define-key map [menu-bar immediate view]
509 '("View This File" . tar-view))
510 (define-key map [menu-bar immediate display]
511 '("Display in Other Window" . tar-display-other-window))
512 (define-key map [menu-bar immediate find-file-other-window]
513 '("Find in Other Window" . tar-extract-other-window))
514 (define-key map [menu-bar immediate find-file]
515 '("Find This File" . tar-extract))
517 (define-key map [menu-bar mark]
518 (cons "Mark" (make-sparse-keymap "Mark")))
520 (define-key map [menu-bar mark unmark-all]
521 '("Unmark All" . tar-clear-modification-flags))
522 (define-key map [menu-bar mark deletion]
523 '("Flag" . tar-flag-deleted))
524 (define-key map [menu-bar mark unmark]
525 '("Unflag" . tar-unflag))
527 (define-key map [menu-bar operate]
528 (cons "Operate" (make-sparse-keymap "Operate")))
530 (define-key map [menu-bar operate chown]
531 '("Change Owner..." . tar-chown-entry))
532 (define-key map [menu-bar operate chgrp]
533 '("Change Group..." . tar-chgrp-entry))
534 (define-key map [menu-bar operate chmod]
535 '("Change Mode..." . tar-chmod-entry))
536 (define-key map [menu-bar operate rename]
537 '("Rename to..." . tar-rename-entry))
538 (define-key map [menu-bar operate copy]
539 '("Copy to..." . tar-copy))
540 (define-key map [menu-bar operate expunge]
541 '("Expunge Marked Files" . tar-expunge))
544 "Local keymap for Tar mode listings.")
547 ;; tar mode is suitable only for specially formatted data.
548 (put 'tar-mode 'mode-class 'special)
549 (put 'tar-subfile-mode 'mode-class 'special)
552 (define-derived-mode tar-mode nil "Tar"
553 "Major mode for viewing a tar file as a dired-like listing of its contents.
554 You can move around using the usual cursor motion commands.
555 Letters no longer insert themselves.
556 Type `e' to pull a file out of the tar file and into its own buffer;
557 or click mouse-2 on the file's line in the Tar mode buffer.
558 Type `c' to copy an entry from the tar file into another file on disk.
560 If you edit a sub-file of this archive (as with the `e' command) and
561 save it with \\[save-buffer], the contents of that buffer will be
562 saved back into the tar-file buffer; in this way you can edit a file
563 inside of a tar archive without extracting it and re-archiving it.
565 See also: variables `tar-update-datestamp' and `tar-anal-blocksize'.
567 ;; this is not interactive because you shouldn't be turning this
568 ;; mode on and off. You can corrupt things that way.
569 ;; rms: with permanent locals, it should now be possible to make this work
570 ;; interactively in some reasonable fashion.
571 (make-local-variable 'tar-header-offset)
572 (make-local-variable 'tar-parse-info)
573 (set (make-local-variable 'require-final-newline) nil) ; binary data, dude...
574 (set (make-local-variable 'revert-buffer-function) 'tar-mode-revert)
575 (set (make-local-variable 'local-enable-local-variables) nil)
576 (set (make-local-variable 'next-line-add-newlines) nil)
577 ;; Prevent loss of data when saving the file.
578 (set (make-local-variable 'file-precious-flag) t)
580 (set (make-local-variable 'write-contents-functions) '(tar-mode-write-file))
581 (buffer-disable-undo)
583 (if (and (boundp 'tar-header-offset) tar-header-offset)
584 (narrow-to-region (point-min) (byte-to-position tar-header-offset))
585 (tar-summarize-buffer)
589 (defun tar-subfile-mode (p)
590 "Minor mode for editing an element of a tar-file.
591 This mode arranges for \"saving\" this buffer to write the data
592 into the tar-file buffer that it came from. The changes will actually
593 appear on disk when you save the tar-file's buffer."
595 (or (and (boundp 'tar-superior-buffer) tar-superior-buffer)
596 (error "This buffer is not an element of a tar file"))
597 ;; Don't do this, because it is redundant and wastes mode line space.
598 ;; (or (assq 'tar-subfile-mode minor-mode-alist)
599 ;; (setq minor-mode-alist (append minor-mode-alist
600 ;; (list '(tar-subfile-mode " TarFile")))))
601 (make-local-variable 'tar-subfile-mode)
602 (setq tar-subfile-mode
604 (not tar-subfile-mode)
605 (> (prefix-numeric-value p) 0)))
606 (cond (tar-subfile-mode
607 (add-hook 'write-file-functions 'tar-subfile-save-buffer nil t)
608 ;; turn off auto-save.
610 (setq buffer-auto-save-file-name nil)
611 (run-hooks 'tar-subfile-mode-hook))
613 (remove-hook 'write-file-functions 'tar-subfile-save-buffer t))))
616 ;; Revert the buffer and recompute the dired-like listing.
617 (defun tar-mode-revert (&optional no-auto-save no-confirm)
618 (let ((revert-buffer-function nil)
619 (old-offset tar-header-offset)
621 (setq tar-header-offset nil)
623 (and (revert-buffer t no-confirm)
627 ;; If the revert was canceled,
628 ;; put back the old value of tar-header-offset.
630 (setq tar-header-offset old-offset)))))
633 (defun tar-next-line (arg)
634 "Move cursor vertically down ARG lines and to the start of the filename."
637 (if (eobp) nil (forward-char (if tar-mode-show-date 54 36))))
639 (defun tar-previous-line (arg)
640 "Move cursor vertically up ARG lines and to the start of the filename."
642 (tar-next-line (- arg)))
644 (defun tar-current-descriptor (&optional noerror)
645 "Return the tar-descriptor of the current line, or signals an error."
646 ;; I wish lines had plists, like in ZMACS...
647 (or (nth (count-lines (point-min)
648 (save-excursion (beginning-of-line) (point)))
652 (error "This line does not describe a tar-file entry"))))
654 (defun tar-get-descriptor ()
655 (let* ((descriptor (tar-current-descriptor))
656 (tokens (tar-desc-tokens descriptor))
657 (size (tar-header-size tokens))
658 (link-p (tar-header-link-type tokens)))
660 (error "This is a %s, not a real file"
661 (cond ((eq link-p 5) "directory")
662 ((eq link-p 20) "tar directory header")
663 ((eq link-p 28) "next has longname")
664 ((eq link-p 29) "multivolume-continuation")
665 ((eq link-p 35) "sparse entry")
666 ((eq link-p 38) "volume header")
668 (if (zerop size) (error "This is a zero-length file"))
671 (defun tar-mouse-extract (event)
672 "Extract a file whose tar directory line you click on."
675 (set-buffer (window-buffer (posn-window (event-end event))))
677 (goto-char (posn-point (event-end event)))
678 ;; Just make sure this doesn't get an error.
679 (tar-get-descriptor)))
680 (select-window (posn-window (event-end event)))
681 (goto-char (posn-point (event-end event)))
684 (defun tar-extract (&optional other-window-p)
685 "In Tar mode, extract this entry of the tar file into its own buffer."
687 (let* ((view-p (eq other-window-p 'view))
688 (descriptor (tar-get-descriptor))
689 (tokens (tar-desc-tokens descriptor))
690 (name (tar-header-name tokens))
691 (size (tar-header-size tokens))
692 (start (+ (tar-desc-data-start descriptor)
693 (- tar-header-offset (point-min))))
694 (end (+ start size)))
695 (let* ((tar-buffer (current-buffer))
696 (tar-buffer-multibyte enable-multibyte-characters)
697 (tarname (buffer-name))
698 (bufname (concat (file-name-nondirectory name)
702 (read-only-p (or buffer-read-only view-p))
703 (new-buffer-file-name (expand-file-name
704 ;; `:' is not allowed on Windows
705 (concat tarname "!" name)))
706 (buffer (get-file-buffer new-buffer-file-name))
709 (setq buffer (generate-new-buffer bufname))
710 (setq bufname (buffer-name buffer))
711 (setq just-created t)
715 (set-buffer-multibyte nil)
718 (let ((buffer-undo-list t))
719 (if enable-multibyte-characters
721 ;; We must avoid unibyte->multibyte conversion.
722 (set-buffer-multibyte nil)
723 (insert-buffer-substring tar-buffer start end)
724 (set-buffer-multibyte t))
725 (insert-buffer-substring tar-buffer start end))
726 (goto-char (point-min))
727 (setq buffer-file-name new-buffer-file-name)
728 (setq buffer-file-truename
729 (abbreviate-file-name buffer-file-name))
730 ;; We need to mimic the parts of insert-file-contents
731 ;; which determine the coding-system and decode the text.
733 (or coding-system-for-read
734 (and set-auto-coding-function
736 (funcall set-auto-coding-function
737 name (- (point-max) (point)))))
738 (car (find-operation-coding-system
739 'insert-file-contents
740 (cons name (current-buffer)) t))))
741 (multibyte enable-multibyte-characters)
742 (detected (detect-coding-region
744 (min (+ (point-min) 16384) (point-max)) t)))
746 (or (numberp (coding-system-eol-type coding))
747 (vectorp (coding-system-eol-type detected))
748 (setq coding (coding-system-change-eol-conversion
750 (coding-system-eol-type detected))))
752 (find-new-buffer-file-coding-system detected)))
753 (if (or (eq coding 'no-conversion)
754 (eq (coding-system-type coding) 5))
755 (setq multibyte (set-buffer-multibyte nil)))
758 (coding-system-change-text-conversion
760 (decode-coding-region (point-min) (point-max) coding)
761 (set-buffer-file-coding-system coding))
762 ;; Set the default-directory to the dir of the
764 (setq default-directory
766 (set-buffer tar-buffer)
768 (normal-mode) ; pick a mode.
769 (rename-buffer bufname)
770 (make-local-variable 'tar-superior-buffer)
771 (make-local-variable 'tar-superior-descriptor)
772 (setq tar-superior-buffer tar-buffer)
773 (setq tar-superior-descriptor descriptor)
774 (setq buffer-read-only read-only-p)
775 (set-buffer-modified-p nil))
776 (tar-subfile-mode 1))
777 (set-buffer tar-buffer))
778 (narrow-to-region (point-min) tar-header-offset)
779 (set-buffer-multibyte tar-buffer-multibyte)))
781 (view-buffer buffer (and just-created 'kill-buffer))
782 (if (eq other-window-p 'display)
783 (display-buffer buffer)
785 (switch-to-buffer-other-window buffer)
786 (switch-to-buffer buffer)))))))
789 (defun tar-extract-other-window ()
790 "In Tar mode, find this entry of the tar file in another window."
794 (defun tar-display-other-window ()
795 "In Tar mode, display this entry of the tar file in another window."
797 (tar-extract 'display))
800 "In Tar mode, view the tar file entry on this line."
805 (defun tar-read-file-name (&optional prompt)
806 "Read a file name with this line's entry as the default."
807 (or prompt (setq prompt "Copy to: "))
808 (let* ((default-file (expand-file-name
809 (tar-header-name (tar-desc-tokens
810 (tar-current-descriptor)))))
811 (target (expand-file-name
812 (read-file-name prompt
813 (file-name-directory default-file)
815 (if (or (string= "" (file-name-nondirectory target))
816 (file-directory-p target))
817 (setq target (concat (if (string-match "/$" target)
818 (substring target 0 (1- (match-end 0)))
821 (file-name-nondirectory default-file))))
825 (defun tar-copy (&optional to-file)
826 "In Tar mode, extract this entry of the tar file into a file on disk.
827 If TO-FILE is not supplied, it is prompted for, defaulting to the name of
828 the current tar-entry."
829 (interactive (list (tar-read-file-name)))
830 (let* ((descriptor (tar-get-descriptor))
831 (tokens (tar-desc-tokens descriptor))
832 (name (tar-header-name tokens))
833 (size (tar-header-size tokens))
834 (start (+ (tar-desc-data-start descriptor)
835 (- tar-header-offset (point-min))))
837 (multibyte enable-multibyte-characters)
838 (inhibit-file-name-handlers inhibit-file-name-handlers)
839 (inhibit-file-name-operation inhibit-file-name-operation))
842 ;; Inhibit compressing a subfile again if *both* name and
843 ;; to-file are handled by jka-compr
844 (if (and (eq (find-file-name-handler name 'write-region) 'jka-compr-handler)
845 (eq (find-file-name-handler to-file 'write-region) 'jka-compr-handler))
846 (setq inhibit-file-name-handlers
847 (cons 'jka-compr-handler
848 (and (eq inhibit-file-name-operation 'write-region)
849 inhibit-file-name-handlers))
850 inhibit-file-name-operation 'write-region))
852 (let ((coding-system-for-write 'no-conversion))
853 (set-buffer-multibyte nil)
854 (write-region start end to-file nil nil nil t))
855 (set-buffer-multibyte multibyte)))
856 (message "Copied tar entry %s to %s" name to-file)))
858 (defun tar-flag-deleted (p &optional unflag)
859 "In Tar mode, mark this sub-file to be deleted from the tar file.
860 With a prefix argument, mark that many files."
864 (if (tar-current-descriptor unflag) ; barf if we're not on an entry-line.
867 (insert (if unflag " " "D"))))
868 (forward-line (if (< p 0) -1 1)))
869 (if (eobp) nil (forward-char 36)))
871 (defun tar-unflag (p)
872 "In Tar mode, un-mark this sub-file if it is marked to be deleted.
873 With a prefix argument, un-mark that many files forward."
875 (tar-flag-deleted p t))
877 (defun tar-unflag-backwards (p)
878 "In Tar mode, un-mark this sub-file if it is marked to be deleted.
879 With a prefix argument, un-mark that many files backward."
881 (tar-flag-deleted (- p) t))
884 ;; When this function is called, it is sure that the buffer is unibyte.
885 (defun tar-expunge-internal ()
886 "Expunge the tar-entry specified by the current line."
887 (let* ((descriptor (tar-current-descriptor))
888 (tokens (tar-desc-tokens descriptor))
889 ;; (line (tar-desc-data-start descriptor))
890 (name (tar-header-name tokens))
891 (size (tar-header-size tokens))
892 (link-p (tar-header-link-type tokens))
893 (start (tar-desc-data-start descriptor))
894 (following-descs (cdr (memq descriptor tar-parse-info))))
895 (if link-p (setq size 0)) ; size lies for hard-links.
897 ;; delete the current line...
899 (let ((line-start (point)))
900 (end-of-line) (forward-char)
901 ;; decrement the header-pointer to be in sync...
902 (setq tar-header-offset (- tar-header-offset (- (point) line-start)))
903 (delete-region line-start (point)))
905 ;; delete the data pointer...
906 (setq tar-parse-info (delq descriptor tar-parse-info))
908 ;; delete the data from inside the file...
910 (let* ((data-start (+ start (- tar-header-offset (point-min)) -512))
911 (data-end (+ data-start 512 (ash (ash (+ size 511) -9) 9))))
912 (delete-region data-start data-end)
914 ;; and finally, decrement the start-pointers of all following
915 ;; entries in the archive. This is a pig when deleting a bunch
916 ;; of files at once - we could optimize this to only do the
917 ;; iteration over the files that remain, or only iterate up to
918 ;; the next file to be deleted.
919 (let ((data-length (- data-end data-start)))
920 (dolist (desc following-descs)
921 (tar-setf (tar-desc-data-start desc)
922 (- (tar-desc-data-start desc) data-length))))
924 (narrow-to-region (point-min) tar-header-offset))
927 (defun tar-expunge (&optional noconfirm)
928 "In Tar mode, delete all the archived files flagged for deletion.
929 This does not modify the disk image; you must save the tar file itself
930 for this to be permanent."
933 (y-or-n-p "Expunge files marked for deletion? "))
935 (multibyte enable-multibyte-characters))
938 (set-buffer-multibyte nil)
939 (goto-char (point-min))
942 (progn (tar-expunge-internal)
945 ;; after doing the deletions, add any padding that may be necessary.
946 (tar-pad-to-blocksize)
948 (set-buffer-multibyte multibyte)
949 (narrow-to-region (point-min) tar-header-offset))
951 (message "Nothing to expunge.")
952 (message "%s files expunged. Be sure to save this buffer." n)))))
955 (defun tar-clear-modification-flags ()
956 "Remove the stars at the beginning of each line."
959 (goto-char (point-min))
960 (while (< (position-bytes (point)) tar-header-offset)
961 (if (not (eq (following-char) ?\ ))
962 (progn (delete-char 1) (insert " ")))
966 (defun tar-chown-entry (new-uid)
967 "Change the user-id associated with this entry in the tar file.
968 If this tar file was written by GNU tar, then you will be able to edit
969 the user id as a string; otherwise, you must edit it as a number.
970 You can force editing as a number by calling this with a prefix arg.
971 This does not modify the disk image; you must save the tar file itself
972 for this to be permanent."
974 (let ((tokens (tar-desc-tokens (tar-current-descriptor))))
975 (if (or current-prefix-arg
976 (not (tar-header-magic tokens)))
978 (while (not (numberp (setq n (read-minibuffer
980 (format "%s" (tar-header-uid tokens)))))))
982 (read-string "New UID string: " (tar-header-uname tokens))))))
983 (cond ((stringp new-uid)
984 (tar-setf (tar-header-uname (tar-desc-tokens (tar-current-descriptor)))
986 (tar-alter-one-field tar-uname-offset (concat new-uid "\000")))
988 (tar-setf (tar-header-uid (tar-desc-tokens (tar-current-descriptor)))
990 (tar-alter-one-field tar-uid-offset
991 (concat (substring (format "%6o" new-uid) 0 6) "\000 ")))))
994 (defun tar-chgrp-entry (new-gid)
995 "Change the group-id associated with this entry in the tar file.
996 If this tar file was written by GNU tar, then you will be able to edit
997 the group id as a string; otherwise, you must edit it as a number.
998 You can force editing as a number by calling this with a prefix arg.
999 This does not modify the disk image; you must save the tar file itself
1000 for this to be permanent."
1002 (let ((tokens (tar-desc-tokens (tar-current-descriptor))))
1003 (if (or current-prefix-arg
1004 (not (tar-header-magic tokens)))
1006 (while (not (numberp (setq n (read-minibuffer
1008 (format "%s" (tar-header-gid tokens)))))))
1010 (read-string "New GID string: " (tar-header-gname tokens))))))
1011 (cond ((stringp new-gid)
1012 (tar-setf (tar-header-gname (tar-desc-tokens (tar-current-descriptor)))
1014 (tar-alter-one-field tar-gname-offset
1015 (concat new-gid "\000")))
1017 (tar-setf (tar-header-gid (tar-desc-tokens (tar-current-descriptor)))
1019 (tar-alter-one-field tar-gid-offset
1020 (concat (substring (format "%6o" new-gid) 0 6) "\000 ")))))
1022 (defun tar-rename-entry (new-name)
1023 "Change the name associated with this entry in the tar file.
1024 This does not modify the disk image; you must save the tar file itself
1025 for this to be permanent."
1027 (list (read-string "New name: "
1028 (tar-header-name (tar-desc-tokens (tar-current-descriptor))))))
1029 (if (string= "" new-name) (error "zero length name"))
1030 (if (> (length new-name) 98) (error "name too long"))
1031 (tar-setf (tar-header-name (tar-desc-tokens (tar-current-descriptor)))
1033 (if (multibyte-string-p new-name)
1034 (setq new-name (encode-coding-string new-name
1035 (or file-name-coding-system
1036 default-file-name-coding-system))))
1037 (tar-alter-one-field 0
1038 (substring (concat new-name (make-string 99 0)) 0 99)))
1041 (defun tar-chmod-entry (new-mode)
1042 "Change the protection bits associated with this entry in the tar file.
1043 This does not modify the disk image; you must save the tar file itself
1044 for this to be permanent."
1045 (interactive (list (tar-parse-octal-integer-safe
1046 (read-string "New protection (octal): "))))
1047 (tar-setf (tar-header-mode (tar-desc-tokens (tar-current-descriptor)))
1049 (tar-alter-one-field tar-mode-offset
1050 (concat (substring (format "%6o" new-mode) 0 6) "\000 ")))
1053 (defun tar-alter-one-field (data-position new-data-string)
1054 (let* ((descriptor (tar-current-descriptor))
1055 (tokens (tar-desc-tokens descriptor))
1056 (multibyte enable-multibyte-characters))
1060 ;; update the header-line.
1064 (delete-region p (point))
1065 (insert (tar-header-block-summarize tokens) "\n")
1066 (setq tar-header-offset (position-bytes (point-max))))
1069 (set-buffer-multibyte nil)
1070 (let* ((start (+ (tar-desc-data-start descriptor)
1071 (- tar-header-offset (point-min))
1074 ;; delete the old field and insert a new one.
1075 (goto-char (+ start data-position))
1076 (delete-region (point) (+ (point) (length new-data-string))) ; <--
1077 (insert new-data-string) ; <--
1079 ;; compute a new checksum and insert it.
1080 (let ((chk (tar-header-block-checksum
1081 (buffer-substring start (+ start 512)))))
1082 (goto-char (+ start tar-chk-offset))
1083 (delete-region (point) (+ (point) 8))
1084 (insert (format "%6o" chk))
1087 (tar-setf (tar-header-checksum tokens) chk)
1089 ;; ok, make sure we didn't botch it.
1090 (tar-header-block-check-checksum
1091 (buffer-substring start (+ start 512))
1092 chk (tar-header-name tokens))
1094 (narrow-to-region (point-min) tar-header-offset)
1095 (set-buffer-multibyte multibyte)
1096 (tar-next-line 0))))
1099 (defun tar-octal-time (timeval)
1100 ;; Format a timestamp as 11 octal digits. Ghod, I hope this works...
1101 (let ((hibits (car timeval)) (lobits (car (cdr timeval))))
1102 (format "%05o%01o%05o"
1104 (logior (lsh (logand 3 hibits) 1)
1105 (if (> (logand lobits 32768) 0) 1 0))
1106 (logand 32767 lobits)
1109 (defun tar-subfile-save-buffer ()
1110 "In tar subfile mode, save this buffer into its parent tar-file buffer.
1111 This doesn't write anything to disk; you must save the parent tar-file buffer
1112 to make your changes permanent."
1114 (if (not (and (boundp 'tar-superior-buffer) tar-superior-buffer))
1115 (error "This buffer has no superior tar file buffer"))
1116 (if (not (and (boundp 'tar-superior-descriptor) tar-superior-descriptor))
1117 (error "This buffer doesn't have an index into its superior tar file!"))
1119 (let ((subfile (current-buffer))
1120 (subfile-multibyte enable-multibyte-characters)
1121 (coding buffer-file-coding-system)
1122 (descriptor tar-superior-descriptor)
1124 ;; We must make the current buffer unibyte temporarily to avoid
1125 ;; multibyte->unibyte conversion in `insert-buffer-substring'.
1126 (set-buffer-multibyte nil)
1127 (setq subfile-size (buffer-size))
1128 (set-buffer tar-superior-buffer)
1129 (let* ((tokens (tar-desc-tokens descriptor))
1130 (start (tar-desc-data-start descriptor))
1131 (name (tar-header-name tokens))
1132 (size (tar-header-size tokens))
1133 (size-pad (ash (ash (+ size 511) -9) 9))
1134 (head (memq descriptor tar-parse-info))
1135 (following-descs (cdr head))
1136 (tar-buffer-multibyte enable-multibyte-characters))
1138 (error "Can't find this tar file entry in its parent tar file!"))
1142 (set-buffer-multibyte nil)
1143 ;; delete the old data...
1144 (let* ((data-start (+ start (- tar-header-offset (point-min))))
1145 (data-end (+ data-start (ash (ash (+ size 511) -9) 9))))
1146 (delete-region data-start data-end)
1147 ;; insert the new data...
1148 (goto-char data-start)
1149 (insert-buffer-substring subfile)
1151 (encode-coding-region
1152 data-start (+ data-start subfile-size) coding))
1154 ;; pad the new data out to a multiple of 512...
1155 (let ((subfile-size-pad (ash (ash (+ subfile-size 511) -9) 9)))
1156 (goto-char (+ data-start subfile-size))
1157 (insert (make-string (- subfile-size-pad subfile-size) 0))
1159 ;; update the data pointer of this and all following files...
1160 (tar-setf (tar-header-size tokens) subfile-size)
1161 (let ((difference (- subfile-size-pad size-pad)))
1162 (dolist (desc following-descs)
1163 (tar-setf (tar-desc-data-start desc)
1164 (+ (tar-desc-data-start desc) difference))))
1166 ;; Update the size field in the header block.
1167 (let ((header-start (- data-start 512)))
1168 (goto-char (+ header-start tar-size-offset))
1169 (delete-region (point) (+ (point) 12))
1170 (insert (format "%11o" subfile-size))
1173 ;; Maybe update the datestamp.
1174 (if (not tar-update-datestamp)
1176 (goto-char (+ header-start tar-time-offset))
1177 (delete-region (point) (+ (point) 12))
1178 (insert (tar-octal-time (current-time)))
1181 ;; compute a new checksum and insert it.
1182 (let ((chk (tar-header-block-checksum
1183 (buffer-substring header-start data-start))))
1184 (goto-char (+ header-start tar-chk-offset))
1185 (delete-region (point) (+ (point) 8))
1186 (insert (format "%6o" chk))
1189 (tar-setf (tar-header-checksum tokens) chk)))
1191 ;; alter the descriptor-line...
1193 (let ((position (- (length tar-parse-info) (length head))))
1194 (goto-char (point-min))
1195 (next-line position)
1199 (m (set-marker (make-marker) tar-header-offset)))
1201 (setq after (point))
1202 ;; Insert the new text after the old, before deleting,
1203 ;; to preserve the window start.
1204 (let ((line (tar-header-block-summarize tokens t)))
1205 (insert-before-markers (string-as-unibyte line) "\n"))
1206 (delete-region p after)
1207 (setq tar-header-offset (marker-position m)))
1209 ;; after doing the insertion, add any final padding that may be necessary.
1210 (tar-pad-to-blocksize))
1211 (narrow-to-region (point-min) tar-header-offset)
1212 (set-buffer-multibyte tar-buffer-multibyte)))
1213 (set-buffer-modified-p t) ; mark the tar file as modified
1215 (set-buffer subfile)
1216 ;; Restore the buffer multibyteness.
1217 (set-buffer-multibyte subfile-multibyte)
1218 (set-buffer-modified-p nil) ; mark the tar subfile as unmodified
1219 (message "Saved into tar-buffer `%s'. Be sure to save that buffer!"
1220 (buffer-name tar-superior-buffer))
1221 ;; Prevent basic-save-buffer from changing our coding-system.
1222 (setq last-coding-system-used buffer-file-coding-system)
1223 ;; Prevent ordinary saving from happening.
1227 ;; When this function is called, it is sure that the buffer is unibyte.
1228 (defun tar-pad-to-blocksize ()
1229 "If we are being anal about tar file blocksizes, fix up the current buffer.
1230 Leaves the region wide."
1231 (if (null tar-anal-blocksize)
1234 (let* ((last-desc (nth (1- (length tar-parse-info)) tar-parse-info))
1235 (start (tar-desc-data-start last-desc))
1236 (tokens (tar-desc-tokens last-desc))
1237 (link-p (tar-header-link-type tokens))
1238 (size (if link-p 0 (tar-header-size tokens)))
1239 (data-end (+ start size))
1240 (bbytes (ash tar-anal-blocksize 9))
1241 (pad-to (+ bbytes (* bbytes (/ (- data-end (point-min)) bbytes))))
1242 (inhibit-read-only t) ; ##
1244 ;; If the padding after the last data is too long, delete some;
1245 ;; else insert some until we are padded out to the right number of blocks.
1247 (let ((goal-end (+ (or tar-header-offset 0) pad-to)))
1248 (if (> (point-max) goal-end)
1249 (delete-region goal-end (point-max))
1250 (goto-char (point-max))
1251 (insert (make-string (- goal-end (point-max)) ?\0)))))))
1254 ;; Used in write-file-hook to write tar-files out correctly.
1255 (defun tar-mode-write-file ()
1259 ;; Doing this here confuses things - the region gets left too wide!
1260 ;; I suppose this is run in a context where changing the buffer is bad.
1261 ;; (tar-pad-to-blocksize)
1262 ;; tar-header-offset turns out to be null for files fetched with W3,
1264 (let ((coding-system-for-write 'no-conversion))
1265 (write-region (if tar-header-offset
1266 (byte-to-position tar-header-offset)
1269 buffer-file-name nil t))
1270 (tar-clear-modification-flags)
1271 (set-buffer-modified-p nil))
1272 (narrow-to-region (point-min) (byte-to-position tar-header-offset)))
1273 ;; Return t because we've written the file.
1278 ;; arch-tag: 8a585a4a-340e-42c2-89e7-d3b1013a4b78
1279 ;;; tar-mode.el ends here