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, 2007, 2008, 2009, 2010, 2011, 2012
5 ;; Free Software Foundation, Inc.
7 ;; Author: Jamie Zawinski <jwz@lucid.com>
9 ;; Created: 04 Apr 1990
12 ;; This file is part of GNU Emacs.
14 ;; GNU Emacs is free software: you can redistribute it and/or modify
15 ;; it under the terms of the GNU General Public License as published by
16 ;; the Free Software Foundation, either version 3 of the License, or
17 ;; (at your option) any later version.
19 ;; GNU Emacs is distributed in the hope that it will be useful,
20 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
21 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 ;; GNU General Public License for more details.
24 ;; You should have received a copy of the GNU General Public License
25 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
29 ;; This package attempts to make dealing with Unix 'tar' archives easier.
30 ;; When this code is loaded, visiting a file whose name ends in '.tar' will
31 ;; cause the contents of that archive file to be displayed in a Dired-like
32 ;; listing. It is then possible to use the customary Dired keybindings to
33 ;; extract sub-files from that archive, either by reading them into their own
34 ;; editor buffers, or by copying them directly to arbitrary files on disk.
35 ;; It is also possible to delete sub-files from within the tar file and write
36 ;; the modified archive back to disk, or to edit sub-files within the archive
37 ;; and re-insert the modified files into the archive. See the documentation
38 ;; string of tar-mode for more info.
40 ;; This code now understands the extra fields that GNU tar adds to tar files.
42 ;; This interacts correctly with "uncompress.el" in the Emacs library,
45 ;; (autoload 'uncompress-while-visiting "uncompress")
46 ;; (setq auto-mode-alist (cons '("\\.Z$" . uncompress-while-visiting)
49 ;; Do not attempt to use tar-mode.el with crypt.el, you will lose.
51 ;; *************** TO DO ***************
53 ;; o chmod should understand "a+x,og-w".
55 ;; o It's not possible to add a NEW file to a tar archive; not that
56 ;; important, but still...
58 ;; o The code is less efficient that it could be - in a lot of places, I
59 ;; pull a 512-character string out of the buffer and parse it, when I could
60 ;; be parsing it in place, not garbaging a string. Should redo that.
62 ;; o I'd like a command that searches for a string/regexp in every subfile
63 ;; of an archive, where <esc> would leave you in a subfile-edit buffer.
64 ;; (Like the Meta-R command of the Zmacs mail reader.)
66 ;; o Sometimes (but not always) reverting the tar-file buffer does not
67 ;; re-grind the listing, and you are staring at the binary tar data.
68 ;; Typing 'g' again immediately after that will always revert and re-grind
69 ;; it, though. I have no idea why this happens.
71 ;; o Tar-mode interacts poorly with crypt.el and zcat.el because the tar
72 ;; write-file-hook actually writes the file. Instead it should remove the
73 ;; header (and conspire to put it back afterwards) so that other write-file
74 ;; hooks which frob the buffer have a chance to do their dirty work. There
75 ;; might be a problem if the tar write-file-hook does not come *first* on
78 ;; o Block files, sparse files, continuation files, and the various header
79 ;; types aren't editable. Actually I don't know that they work at all.
83 ;; Why does tar-mode edit the file itself instead of using tar?
85 ;; That means that you can edit tar files which you don't have room for
86 ;; on your local disk.
88 ;; I don't know about recent features in gnu tar, but old versions of tar
89 ;; can't replace a file in the middle of a tar file with a new version.
90 ;; Tar-mode can. I don't think tar can do things like chmod the subfiles.
91 ;; An implementation which involved unpacking and repacking the file into
92 ;; some scratch directory would be very wasteful, and wouldn't be able to
93 ;; preserve the file owners.
97 ;; - Rename on ././@LongLink files
98 ;; - Revert confirmation displays the raw data temporarily.
102 (eval-when-compile (require 'cl
))
105 "Simple editing of tar files."
109 (defcustom tar-anal-blocksize
20
110 "The blocksize of tar files written by Emacs, or nil, meaning don't care.
111 The blocksize of a tar file is not really the size of the blocks; rather, it is
112 the number of blocks written with one system call. When tarring to a tape,
113 this is the size of the *tape* blocks, but when writing to a file, it doesn't
114 matter much. The only noticeable difference is that if a tar file does not
115 have a blocksize of 20, tar will tell you that; all this really controls is
116 how many null padding bytes go on the end of the tar file."
117 :type
'(choice integer
(const nil
))
120 (defcustom tar-update-datestamp nil
121 "Non-nil means Tar mode should play fast and loose with sub-file datestamps.
122 If this is true, then editing and saving a tar file entry back into its
123 tar file will update its datestamp. If false, the datestamp is unchanged.
124 You may or may not want this - it is good in that you can tell when a file
125 in a tar archive has been changed, but it is bad for the same reason that
126 editing a file in the tar archive at all is bad - the changed version of
127 the file never exists on disk."
131 (defcustom tar-mode-show-date nil
132 "Non-nil means Tar mode should show the date/time of each subfile.
133 This information is useful, but it takes screen space away from file names."
137 (defvar tar-parse-info nil
)
138 (defvar tar-superior-buffer nil
)
139 (defvar tar-superior-descriptor nil
)
140 (defvar tar-subfile-mode nil
)
141 (defvar tar-file-name-coding-system nil
)
143 (put 'tar-superior-buffer
'permanent-local t
)
144 (put 'tar-superior-descriptor
'permanent-local t
)
146 ;; The Tar data is made up of bytes and better manipulated as bytes
147 ;; and can be very large, so insert/delete can be costly. The summary we
148 ;; want to display may contain non-ascci chars, of course, so we'd like it
149 ;; to be multibyte. We used to keep both in the same buffer and switch
150 ;; from/to uni/multibyte. But this had several downsides:
151 ;; - set-buffer-multibyte has an O(N^2) worst case that tends to be triggered
152 ;; here, so it gets atrociously slow on large Tar files.
153 ;; - need to widen/narrow the buffer to show/hide the raw data, and need to
154 ;; maintain a tar-header-offset that keeps track of the boundary between
156 ;; - can't use markers because they're not preserved by set-buffer-multibyte.
157 ;; So instead, we now keep the two pieces of data in separate buffers, and
158 ;; use the new buffer-swap-text primitive when we need to change which data
159 ;; is associated with "the" buffer.
160 (defvar tar-data-buffer nil
"Buffer that holds the actual raw tar bytes.")
161 (make-variable-buffer-local 'tar-data-buffer
)
163 (defvar tar-data-swapped nil
164 "If non-nil, `tar-data-buffer' indeed holds raw tar bytes.")
165 (make-variable-buffer-local 'tar-data-swapped
)
167 (defun tar-data-swapped-p ()
168 "Return non-nil if the tar-data is in `tar-data-buffer'."
169 (and (buffer-live-p tar-data-buffer
)
170 ;; Sanity check to try and make sure tar-data-swapped tracks the swap
171 ;; state correctly: the raw data is expected to be always larger than
174 (assert (or (= (buffer-size tar-data-buffer
) (buffer-size))
176 (> (buffer-size tar-data-buffer
) (buffer-size)))))
179 (defun tar-swap-data ()
180 "Swap buffer contents between current buffer and `tar-data-buffer'.
181 Preserve the modified states of the buffers and set `buffer-swapped-with'."
182 (let ((data-buffer-modified-p (buffer-modified-p tar-data-buffer
))
183 (current-buffer-modified-p (buffer-modified-p)))
184 (buffer-swap-text tar-data-buffer
)
185 (setq tar-data-swapped
(not tar-data-swapped
))
186 (restore-buffer-modified-p data-buffer-modified-p
)
187 (with-current-buffer tar-data-buffer
188 (restore-buffer-modified-p current-buffer-modified-p
))))
190 ;;; down to business.
192 (defstruct (tar-header
197 make-tar-header
(data-start name mode uid gid size date checksum
198 link-type link-name magic uname gname dmaj dmin
)))
199 data-start name mode uid gid size date checksum link-type link-name
200 magic uname gname dmaj dmin
201 ;; Start of the header can be nil (meaning it's 512 bytes before data-start)
202 ;; or a marker (in case the header uses LongLink thingies).
205 (defconst tar-name-offset
0)
206 (defconst tar-mode-offset
(+ tar-name-offset
100))
207 (defconst tar-uid-offset
(+ tar-mode-offset
8))
208 (defconst tar-gid-offset
(+ tar-uid-offset
8))
209 (defconst tar-size-offset
(+ tar-gid-offset
8))
210 (defconst tar-time-offset
(+ tar-size-offset
12))
211 (defconst tar-chk-offset
(+ tar-time-offset
12))
212 (defconst tar-linkp-offset
(+ tar-chk-offset
8))
213 (defconst tar-link-offset
(+ tar-linkp-offset
1))
214 ;;; GNU-tar specific slots.
215 (defconst tar-magic-offset
(+ tar-link-offset
100))
216 (defconst tar-uname-offset
(+ tar-magic-offset
8))
217 (defconst tar-gname-offset
(+ tar-uname-offset
32))
218 (defconst tar-dmaj-offset
(+ tar-gname-offset
32))
219 (defconst tar-dmin-offset
(+ tar-dmaj-offset
8))
220 (defconst tar-prefix-offset
(+ tar-dmin-offset
8))
221 (defconst tar-end-offset
(+ tar-prefix-offset
155))
223 (defun tar-roundup-512 (s)
224 "Round S up to the next multiple of 512."
225 (ash (ash (+ s
511) -
9) 9))
227 (defun tar-header-block-tokenize (pos coding
)
228 "Return a `tar-header' structure.
229 This is a list of name, mode, uid, gid, size,
230 write-date, checksum, link-type, and link-name."
231 (if (> (+ pos
512) (point-max)) (error "Malformed Tar header"))
232 (assert (zerop (mod (- pos
(point-min)) 512)))
233 (assert (not enable-multibyte-characters
))
234 (let ((string (buffer-substring pos
(setq pos
(+ pos
512)))))
235 (when ;(some 'plusp string) ; <-- oops, massive cycle hog!
236 (or (not (= 0 (aref string
0))) ; This will do.
237 (not (= 0 (aref string
101))))
238 (let* ((name-end tar-mode-offset
)
239 (link-end (1- tar-magic-offset
))
240 (uname-end (1- tar-gname-offset
))
241 (gname-end (1- tar-dmaj-offset
))
242 (link-p (aref string tar-linkp-offset
))
243 (magic-str (substring string tar-magic-offset
244 ;; The magic string is actually 6bytes
245 ;; of magic string plus 2bytes of version
246 ;; which we here ignore.
247 (- tar-uname-offset
2)))
248 ;; The magic string is "ustar\0" for POSIX format, and
249 ;; "ustar " for GNU Tar's format.
250 (uname-valid-p (car (member magic-str
'("ustar " "ustar\0"))))
252 (nulsexp "[^\000]*\000"))
253 (when (string-match nulsexp string tar-name-offset
)
254 (setq name-end
(min name-end
(1- (match-end 0)))))
255 (when (string-match nulsexp string tar-link-offset
)
256 (setq link-end
(min link-end
(1- (match-end 0)))))
257 (when (string-match nulsexp string tar-uname-offset
)
258 (setq uname-end
(min uname-end
(1- (match-end 0)))))
259 (when (string-match nulsexp string tar-gname-offset
)
260 (setq gname-end
(min gname-end
(1- (match-end 0)))))
261 (setq name
(substring string tar-name-offset name-end
)
262 link-p
(if (or (= link-p
0) (= link-p ?
0))
265 (setq linkname
(substring string tar-link-offset link-end
))
266 (when (and (equal uname-valid-p
"ustar\0")
267 (string-match nulsexp string tar-prefix-offset
)
268 (> (match-end 0) (1+ tar-prefix-offset
)))
269 (setq name
(concat (substring string tar-prefix-offset
272 (if (default-value 'enable-multibyte-characters
)
274 (decode-coding-string name coding
)
276 (decode-coding-string linkname coding
)))
277 (if (and (null link-p
) (string-match "/\\'" name
))
278 (setq link-p
5)) ; directory
280 (if (and (equal name
"././@LongLink")
281 ;; Supposedly @LongLink is only used for GNUTAR
282 ;; format (i.e. "ustar ") but some POSIX Tar files
283 ;; (with "ustar\0") have been seen using it as well.
284 (member magic-str
'("ustar " "ustar\0")))
285 ;; This is a GNU Tar long-file-name header.
286 (let* ((size (tar-parse-octal-integer
287 string tar-size-offset tar-time-offset
))
288 ;; -1 so as to strip the terminating 0 byte.
289 (name (decode-coding-string
290 (buffer-substring pos
(+ pos size -
1)) coding
))
291 (descriptor (tar-header-block-tokenize
292 (+ pos
(tar-roundup-512 size
))
295 ((eq link-p
(- ?L ?
0)) ;GNUTYPE_LONGNAME.
296 (setf (tar-header-name descriptor
) name
))
297 ((eq link-p
(- ?K ?
0)) ;GNUTYPE_LONGLINK.
298 (setf (tar-header-link-name descriptor
) name
))
300 (message "Unrecognized GNU Tar @LongLink format")))
301 (setf (tar-header-header-start descriptor
)
302 (copy-marker (- pos
512) t
))
306 (copy-marker pos nil
)
308 (tar-parse-octal-integer string tar-mode-offset tar-uid-offset
)
309 (tar-parse-octal-integer string tar-uid-offset tar-gid-offset
)
310 (tar-parse-octal-integer string tar-gid-offset tar-size-offset
)
311 (tar-parse-octal-integer string tar-size-offset tar-time-offset
)
312 (tar-parse-octal-long-integer string tar-time-offset tar-chk-offset
)
313 (tar-parse-octal-integer string tar-chk-offset tar-linkp-offset
)
318 (decode-coding-string
319 (substring string tar-uname-offset uname-end
) coding
))
321 (decode-coding-string
322 (substring string tar-gname-offset gname-end
) coding
))
323 (tar-parse-octal-integer string tar-dmaj-offset tar-dmin-offset
)
324 (tar-parse-octal-integer string tar-dmin-offset tar-prefix-offset
)
328 (defun tar-header-data-end (descriptor)
329 (let* ((data-start (tar-header-data-start descriptor
))
330 (link-type (tar-header-link-type descriptor
))
331 (size (tar-header-size descriptor
))
333 ;; Foo. There's an extra empty block after these.
334 ((memq link-type
'(20 55)) 512)
337 (if (and (null link-type
) (> size
0))
338 (tar-roundup-512 size
)
341 (defun tar-parse-octal-integer (string &optional start end
)
342 (if (null start
) (setq start
0))
343 (if (null end
) (setq end
(length string
)))
344 (if (= (aref string start
) 0)
348 (setq n
(if (< (aref string start
) ?
0) n
349 (+ (* n
8) (- (aref string start
) ?
0)))
353 (defun tar-parse-octal-long-integer (string &optional start end
)
354 (if (null start
) (setq start
0))
355 (if (null end
) (setq end
(length string
)))
356 (if (= (aref string start
) 0)
361 (if (>= (aref string start
) ?
0)
362 (setq lo
(+ (* lo
8) (- (aref string start
) ?
0))
363 hi
(+ (* hi
8) (ash lo -
16))
364 lo
(logand lo
65535)))
365 (setq start
(1+ start
)))
368 (defun tar-parse-octal-integer-safe (string)
369 (if (zerop (length string
)) (error "empty string"))
371 (if (or (< c ?
0) (> c ?
7))
372 (error "`%c' is not an octal digit" c
)))
374 (tar-parse-octal-integer string
))
377 (defun tar-header-block-checksum (string)
378 "Compute and return a tar-acceptable checksum for this block."
379 (assert (not (multibyte-string-p string
)))
380 (let* ((chk-field-start tar-chk-offset
)
381 (chk-field-end (+ chk-field-start
8))
384 ;; Add up all of the characters except the ones in the checksum field.
385 ;; Add that field as if it were filled with spaces.
386 (while (< i chk-field-start
)
387 (setq sum
(+ sum
(aref string i
))
389 (setq i chk-field-end
)
391 (setq sum
(+ sum
(aref string i
))
395 (defun tar-header-block-check-checksum (hblock desired-checksum file-name
)
396 "Beep and print a warning if the checksum doesn't match."
397 (if (not (= desired-checksum
(tar-header-block-checksum hblock
)))
398 (progn (beep) (message "Invalid checksum for file %s!" file-name
))))
400 (defun tar-clip-time-string (time)
401 (let ((str (current-time-string time
)))
402 (concat " " (substring str
4 16) (substring str
19 24))))
404 (defun tar-grind-file-mode (mode)
405 "Construct a `-rw--r--r--' string indicating MODE.
406 MODE should be an integer which is a file mode value."
408 (if (zerop (logand 256 mode
)) ?- ?r
)
409 (if (zerop (logand 128 mode
)) ?- ?w
)
410 (if (zerop (logand 1024 mode
)) (if (zerop (logand 64 mode
)) ?- ?x
) ?s
)
411 (if (zerop (logand 32 mode
)) ?- ?r
)
412 (if (zerop (logand 16 mode
)) ?- ?w
)
413 (if (zerop (logand 2048 mode
)) (if (zerop (logand 8 mode
)) ?- ?x
) ?s
)
414 (if (zerop (logand 4 mode
)) ?- ?r
)
415 (if (zerop (logand 2 mode
)) ?- ?w
)
416 (if (zerop (logand 1 mode
)) ?- ?x
)))
418 (defun tar-header-block-summarize (tar-hblock &optional mod-p
)
419 "Return a line similar to the output of `tar -vtf'."
420 (let ((name (tar-header-name tar-hblock
))
421 (mode (tar-header-mode tar-hblock
))
422 (uid (tar-header-uid tar-hblock
))
423 (gid (tar-header-gid tar-hblock
))
424 (uname (tar-header-uname tar-hblock
))
425 (gname (tar-header-gname tar-hblock
))
426 (size (tar-header-size tar-hblock
))
427 (time (tar-header-date tar-hblock
))
428 ;; (ck (tar-header-checksum tar-hblock))
429 (type (tar-header-link-type tar-hblock
))
430 (link-name (tar-header-link-name tar-hblock
)))
431 (format "%c%c%s %7s/%-7s %7s%s %s%s"
433 (cond ((or (eq type nil
) (eq type
0)) ?-
)
434 ((eq type
1) ?h
) ; link
435 ((eq type
2) ?l
) ; symlink
436 ((eq type
3) ?c
) ; char special
437 ((eq type
4) ?b
) ; block special
438 ((eq type
5) ?d
) ; directory
439 ((eq type
6) ?p
) ; FIFO/pipe
440 ((eq type
20) ?
*) ; directory listing
441 ((eq type
28) ?L
) ; next has longname
442 ((eq type
29) ?M
) ; multivolume continuation
443 ((eq type
35) ?S
) ; sparse
444 ((eq type
38) ?V
) ; volume header
445 ((eq type
55) ?H
) ; extended pax header
448 (tar-grind-file-mode mode
)
449 (if (= 0 (length uname
)) uid uname
)
450 (if (= 0 (length gname
)) gid gname
)
452 (if tar-mode-show-date
(tar-clip-time-string time
) "")
454 'mouse-face
'highlight
455 'help-echo
"mouse-2: extract this file into a buffer")
456 (if (or (eq type
1) (eq type
2))
457 (concat (if (= type
1) " ==> " " --> ") link-name
)
460 (defun tar-untar-buffer ()
461 "Extract all archive members in the tar-file into the current directory."
463 ;; FIXME: make it work even if we're not in tar-mode.
464 (let ((descriptors tar-parse-info
)) ;Read the var in its buffer.
466 (if (tar-data-swapped-p) tar-data-buffer
(current-buffer))
467 (set-buffer-multibyte nil
) ;Hopefully, a no-op.
468 (dolist (descriptor descriptors
)
469 (let* ((name (tar-header-name descriptor
))
470 (dir (if (eq (tar-header-link-type descriptor
) 5)
472 (file-name-directory name
)))
473 (start (tar-header-data-start descriptor
))
474 (end (+ start
(tar-header-size descriptor
))))
475 (unless (file-directory-p name
)
476 (message "Extracting %s" name
)
477 (if (and dir
(not (file-exists-p dir
)))
478 (make-directory dir t
))
479 (unless (file-directory-p name
)
480 (let ((coding-system-for-write 'no-conversion
))
481 (write-region start end name
)))
482 (set-file-modes name
(tar-header-mode descriptor
))))))))
484 (defun tar-summarize-buffer ()
485 "Parse the contents of the tar file in the current buffer."
486 (assert (tar-data-swapped-p))
487 (let* ((modified (buffer-modified-p))
490 (coding tar-file-name-coding-system
)
492 (with-current-buffer tar-data-buffer
493 (make-progress-reporter "Parsing tar file..."
494 (point-min) (point-max))))
496 (with-current-buffer tar-data-buffer
497 (while (and (< pos
(point-max))
498 (setq descriptor
(tar-header-block-tokenize pos coding
)))
499 (let ((size (tar-header-size descriptor
)))
501 (error "%s has size %s - corrupted"
502 (tar-header-name descriptor
) size
)))
504 ;; This is just too slow. Don't really need it anyway....
505 ;;(tar-header-block-check-checksum
506 ;; hblock (tar-header-block-checksum hblock)
507 ;; (tar-header-name descriptor))
509 (push descriptor result
)
510 (setq pos
(tar-header-data-end descriptor
))
511 (progress-reporter-update progress-reporter pos
)))
513 (set (make-local-variable 'tar-parse-info
) (nreverse result
))
514 ;; A tar file should end with a block or two of nulls,
515 ;; but let's not get a fatal error if it doesn't.
516 (if (null descriptor
)
517 (progress-reporter-done progress-reporter
)
518 (message "Warning: premature EOF parsing tar file"))
519 (goto-char (point-min))
520 (let ((inhibit-read-only t
)
522 (mapconcat 'tar-header-block-summarize tar-parse-info
"\n")))
523 (insert total-summaries
"\n"))
524 (goto-char (point-min))
525 (restore-buffer-modified-p modified
)))
528 (let ((map (make-keymap)))
529 (suppress-keymap map
)
530 (define-key map
" " 'tar-next-line
)
531 (define-key map
"C" 'tar-copy
)
532 (define-key map
"d" 'tar-flag-deleted
)
533 (define-key map
"\^D" 'tar-flag-deleted
)
534 (define-key map
"e" 'tar-extract
)
535 (define-key map
"f" 'tar-extract
)
536 (define-key map
"\C-m" 'tar-extract
)
537 (define-key map
[mouse-2
] 'tar-mouse-extract
)
538 (define-key map
"g" 'revert-buffer
)
539 (define-key map
"h" 'describe-mode
)
540 (define-key map
"n" 'tar-next-line
)
541 (define-key map
"\^N" 'tar-next-line
)
542 (define-key map
[down] 'tar-next-line)
543 (define-key map "o" 'tar-extract-other-window)
544 (define-key map "p" 'tar-previous-line)
545 (define-key map "q" 'quit-window)
546 (define-key map "\^P" 'tar-previous-line)
547 (define-key map [up] 'tar-previous-line)
548 (define-key map "R" 'tar-rename-entry)
549 (define-key map "u" 'tar-unflag)
550 (define-key map "v" 'tar-view)
551 (define-key map "x" 'tar-expunge)
552 (define-key map "\177" 'tar-unflag-backwards)
553 (define-key map "E" 'tar-extract-other-window)
554 (define-key map "M" 'tar-chmod-entry)
555 (define-key map "G" 'tar-chgrp-entry)
556 (define-key map "O" 'tar-chown-entry)
557 ;; Let mouse-1 follow the link.
558 (define-key map [follow-link] 'mouse-face)
560 ;; Make menu bar items.
562 ;; Get rid of the Edit menu bar item to save space.
563 (define-key map [menu-bar edit] 'undefined)
565 (define-key map [menu-bar immediate]
566 (cons "Immediate" (make-sparse-keymap "Immediate")))
568 (define-key map [menu-bar immediate view]
569 '("View This File" . tar-view))
570 (define-key map [menu-bar immediate display]
571 '("Display in Other Window" . tar-display-other-window))
572 (define-key map [menu-bar immediate find-file-other-window]
573 '("Find in Other Window" . tar-extract-other-window))
574 (define-key map [menu-bar immediate find-file]
575 '("Find This File" . tar-extract))
577 (define-key map [menu-bar mark]
578 (cons "Mark" (make-sparse-keymap "Mark")))
580 (define-key map [menu-bar mark unmark-all]
581 '("Unmark All" . tar-clear-modification-flags))
582 (define-key map [menu-bar mark deletion]
583 '("Flag" . tar-flag-deleted))
584 (define-key map [menu-bar mark unmark]
585 '("Unflag" . tar-unflag))
587 (define-key map [menu-bar operate]
588 (cons "Operate" (make-sparse-keymap "Operate")))
590 (define-key map [menu-bar operate chown]
591 '("Change Owner..." . tar-chown-entry))
592 (define-key map [menu-bar operate chgrp]
593 '("Change Group..." . tar-chgrp-entry))
594 (define-key map [menu-bar operate chmod]
595 '("Change Mode..." . tar-chmod-entry))
596 (define-key map [menu-bar operate rename]
597 '("Rename to..." . tar-rename-entry))
598 (define-key map [menu-bar operate copy]
599 '("Copy to..." . tar-copy))
600 (define-key map [menu-bar operate expunge]
601 '("Expunge Marked Files" . tar-expunge))
604 "Local keymap for Tar mode listings.")
607 ;; tar mode is suitable only for specially formatted data.
608 (put 'tar-mode 'mode-class 'special)
609 (put 'tar-subfile-mode 'mode-class 'special)
611 (defun tar-change-major-mode-hook ()
612 ;; Bring the actual Tar data back into the main buffer.
613 (when (tar-data-swapped-p) (tar-swap-data))
614 ;; Throw away the summary.
615 (when (buffer-live-p tar-data-buffer) (kill-buffer tar-data-buffer)))
617 (defun tar-mode-kill-buffer-hook ()
618 (if (buffer-live-p tar-data-buffer) (kill-buffer tar-data-buffer)))
621 (define-derived-mode tar-mode nil "Tar"
622 "Major mode for viewing a tar file as a dired-like listing of its contents.
623 You can move around using the usual cursor motion commands.
624 Letters no longer insert themselves.
625 Type `e' to pull a file out of the tar file and into its own buffer;
626 or click mouse-2 on the file's line in the Tar mode buffer.
627 Type `c' to copy an entry from the tar file into another file on disk.
629 If you edit a sub-file of this archive (as with the `e' command) and
630 save it with \\[save-buffer], the contents of that buffer will be
631 saved back into the tar-file buffer; in this way you can edit a file
632 inside of a tar archive without extracting it and re-archiving it.
634 See also: variables `tar-update-datestamp' and `tar-anal-blocksize'.
636 (make-local-variable 'tar-parse-info)
637 (set (make-local-variable 'require-final-newline) nil) ; binary data, dude...
638 (set (make-local-variable 'local-enable-local-variables) nil)
639 (set (make-local-variable 'next-line-add-newlines) nil)
640 (set (make-local-variable 'tar-file-name-coding-system)
641 (or file-name-coding-system
642 default-file-name-coding-system
643 locale-coding-system))
644 ;; Prevent loss of data when saving the file.
645 (set (make-local-variable 'file-precious-flag) t)
646 (buffer-disable-undo)
648 ;; Now move the Tar data into an auxiliary buffer, so we can use the main
649 ;; buffer for the summary.
650 (assert (not (tar-data-swapped-p)))
651 (set (make-local-variable 'revert-buffer-function) 'tar-mode-revert)
652 ;; We started using write-contents-functions, but this hook is not
653 ;; used during auto-save, so we now use
654 ;; write-region-annotate-functions which hooks at a lower-level.
655 (add-hook 'write-region-annotate-functions 'tar-write-region-annotate nil t)
656 (add-hook 'kill-buffer-hook 'tar-mode-kill-buffer-hook nil t)
657 (add-hook 'change-major-mode-hook 'tar-change-major-mode-hook nil t)
658 ;; Tar data is made of bytes, not chars.
659 (set-buffer-multibyte nil) ;Hopefully a no-op.
660 (set (make-local-variable 'tar-data-buffer)
661 (generate-new-buffer (format " *tar-data %s*"
662 (file-name-nondirectory
663 (or buffer-file-name (buffer-name))))))
667 (tar-summarize-buffer)
670 ;; If summarizing caused an error, then maybe the buffer doesn't contain
671 ;; tar data. Rather than show a mysterious empty buffer, let's
672 ;; revert to fundamental-mode.
674 (signal (car err) (cdr err)))))
677 (defun tar-subfile-mode (p)
678 "Minor mode for editing an element of a tar-file.
679 This mode arranges for \"saving\" this buffer to write the data
680 into the tar-file buffer that it came from. The changes will actually
681 appear on disk when you save the tar-file's buffer."
683 (or (and (boundp 'tar-superior-buffer) tar-superior-buffer)
684 (error "This buffer is not an element of a tar file"))
685 ;; Don't do this, because it is redundant and wastes mode line space.
686 ;; (or (assq 'tar-subfile-mode minor-mode-alist)
687 ;; (setq minor-mode-alist (append minor-mode-alist
688 ;; (list '(tar-subfile-mode " TarFile")))))
689 (make-local-variable 'tar-subfile-mode)
690 (setq tar-subfile-mode
692 (not tar-subfile-mode)
693 (> (prefix-numeric-value p) 0)))
694 (cond (tar-subfile-mode
695 (add-hook 'write-file-functions 'tar-subfile-save-buffer nil t)
696 ;; turn off auto-save.
698 (setq buffer-auto-save-file-name nil)
699 (run-hooks 'tar-subfile-mode-hook))
701 (remove-hook 'write-file-functions 'tar-subfile-save-buffer t))))
704 ;; Revert the buffer and recompute the dired-like listing.
705 (defun tar-mode-revert (&optional no-auto-save no-confirm)
707 (let ((revert-buffer-function nil))
708 (if (tar-data-swapped-p) (tar-swap-data))
709 ;; FIXME: If we ask for confirmation, the user will be temporarily
710 ;; looking at the raw data.
711 (revert-buffer no-auto-save no-confirm 'preserve-modes)
712 ;; Recompute the summary.
713 (if (buffer-live-p tar-data-buffer) (kill-buffer tar-data-buffer))
715 (unless (tar-data-swapped-p) (tar-swap-data))))
718 (defun tar-next-line (arg)
719 "Move cursor vertically down ARG lines and to the start of the filename."
722 (goto-char (or (next-single-property-change (point) 'mouse-face) (point))))
724 (defun tar-previous-line (arg)
725 "Move cursor vertically up ARG lines and to the start of the filename."
727 (tar-next-line (- arg)))
729 (defun tar-current-descriptor (&optional noerror)
730 "Return the tar-descriptor of the current line, or signals an error."
731 ;; I wish lines had plists, like in ZMACS...
732 (or (nth (count-lines (point-min) (line-beginning-position))
736 (error "This line does not describe a tar-file entry"))))
738 (defun tar-get-descriptor ()
739 (let* ((descriptor (tar-current-descriptor))
740 (size (tar-header-size descriptor))
741 (link-p (tar-header-link-type descriptor)))
743 (error "This is %s, not a real file"
744 (cond ((eq link-p 5) "a directory")
745 ((eq link-p 20) "a tar directory header")
746 ((eq link-p 28) "a next has longname")
747 ((eq link-p 29) "a multivolume-continuation")
748 ((eq link-p 35) "a sparse entry")
749 ((eq link-p 38) "a volume header")
750 ((eq link-p 55) "an extended pax header")
752 (if (zerop size) (message "This is a zero-length file"))
755 (defun tar-mouse-extract (event)
756 "Extract a file whose tar directory line you click on."
758 (with-current-buffer (window-buffer (posn-window (event-end event)))
760 (goto-char (posn-point (event-end event)))
761 ;; Just make sure this doesn't get an error.
762 (tar-get-descriptor)))
763 (select-window (posn-window (event-end event)))
764 (goto-char (posn-point (event-end event)))
767 (defun tar-file-name-handler (op &rest args)
768 "Helper function for `tar-extract'."
769 (or (eq op 'file-exists-p)
770 (let ((file-name-handler-alist nil))
773 (defun tar-extract (&optional other-window-p)
774 "In Tar mode, extract this entry of the tar file into its own buffer."
776 (let* ((view-p (eq other-window-p 'view))
777 (descriptor (tar-get-descriptor))
778 (name (tar-header-name descriptor))
779 (size (tar-header-size descriptor))
780 (start (tar-header-data-start descriptor))
781 (end (+ start size)))
782 (let* ((tar-buffer (current-buffer))
783 (tarname (buffer-name))
784 (bufname (concat (file-name-nondirectory name)
788 (read-only-p (or buffer-read-only view-p))
789 (new-buffer-file-name (expand-file-name
790 ;; `:' is not allowed on Windows
792 (if (string-match "/" name)
794 ;; Make sure `name' contains a /
795 ;; so set-auto-mode doesn't try
796 ;; to look at `tarname' for hints.
797 (concat "./" name)))))
798 (buffer (get-file-buffer new-buffer-file-name))
802 (setq buffer (generate-new-buffer bufname))
803 (with-current-buffer buffer
804 (setq undo-list buffer-undo-list
806 (setq bufname (buffer-name buffer))
807 (setq just-created t)
808 (with-current-buffer tar-data-buffer
810 (narrow-to-region start end)
812 (setq coding (or coding-system-for-read
813 (and set-auto-coding-function
814 (funcall set-auto-coding-function
816 ;; The following binding causes
817 ;; find-buffer-file-type-coding-system
818 ;; (defined on dos-w32.el) to act as if
819 ;; the file being extracted existed, so
820 ;; that the file's contents' encoding and
821 ;; EOL format are auto-detected.
822 (let ((file-name-handler-alist
823 '(("" . tar-file-name-handler))))
824 (car (find-operation-coding-system
825 'insert-file-contents
826 (cons name (current-buffer)) t)))))
828 (eq (coding-system-type coding) 'undecided))
829 (setq coding (detect-coding-region start end t)))
830 (if (and (default-value 'enable-multibyte-characters)
831 (coding-system-get coding :for-unibyte))
832 (with-current-buffer buffer
833 (set-buffer-multibyte nil)))
835 (decode-coding-region start end coding buffer)))
836 (with-current-buffer buffer
837 (goto-char (point-min))
838 (setq buffer-file-name new-buffer-file-name)
839 (setq buffer-file-truename
840 (abbreviate-file-name buffer-file-name))
841 ;; Force buffer-file-coding-system to what
842 ;; decode-coding-region actually used.
843 (set-buffer-file-coding-system last-coding-system-used t)
844 ;; Set the default-directory to the dir of the
846 (setq default-directory
847 (with-current-buffer tar-buffer
849 (rename-buffer bufname)
850 (set-buffer-modified-p nil)
851 (setq buffer-undo-list undo-list)
852 (normal-mode) ; pick a mode.
853 (set (make-local-variable 'tar-superior-buffer) tar-buffer)
854 (set (make-local-variable 'tar-superior-descriptor) descriptor)
855 (setq buffer-read-only read-only-p)
856 (tar-subfile-mode 1)))
859 buffer (and just-created 'kill-buffer-if-not-modified))
860 (if (eq other-window-p 'display)
861 (display-buffer buffer)
863 (switch-to-buffer-other-window buffer)
864 (switch-to-buffer buffer)))))))
867 (defun tar-extract-other-window ()
868 "In Tar mode, find this entry of the tar file in another window."
872 (defun tar-display-other-window ()
873 "In Tar mode, display this entry of the tar file in another window."
875 (tar-extract 'display))
878 "In Tar mode, view the tar file entry on this line."
883 (defun tar-read-file-name (&optional prompt)
884 "Read a file name with this line's entry as the default."
885 (or prompt (setq prompt "Copy to: "))
886 (let* ((default-file (expand-file-name
887 (tar-header-name (tar-current-descriptor))))
888 (target (expand-file-name
889 (read-file-name prompt
890 (file-name-directory default-file)
892 (if (or (string= "" (file-name-nondirectory target))
893 (file-directory-p target))
894 (setq target (concat (if (string-match "/$" target)
895 (substring target 0 (1- (match-end 0)))
898 (file-name-nondirectory default-file))))
902 (defun tar-copy (&optional to-file)
903 "In Tar mode, extract this entry of the tar file into a file on disk.
904 If TO-FILE is not supplied, it is prompted for, defaulting to the name of
905 the current tar-entry."
906 (interactive (list (tar-read-file-name)))
907 (let* ((descriptor (tar-get-descriptor))
908 (name (tar-header-name descriptor))
909 (size (tar-header-size descriptor))
910 (start (tar-header-data-start descriptor))
912 (inhibit-file-name-handlers inhibit-file-name-handlers)
913 (inhibit-file-name-operation inhibit-file-name-operation))
915 (if (tar-data-swapped-p) tar-data-buffer (current-buffer))
916 ;; Inhibit compressing a subfile again if *both* name and
917 ;; to-file are handled by jka-compr
918 (if (and (eq (find-file-name-handler name 'write-region)
920 (eq (find-file-name-handler to-file 'write-region)
922 (setq inhibit-file-name-handlers
923 (cons 'jka-compr-handler
924 (and (eq inhibit-file-name-operation 'write-region)
925 inhibit-file-name-handlers))
926 inhibit-file-name-operation 'write-region))
927 (let ((coding-system-for-write 'no-conversion))
928 (write-region start end to-file nil nil nil t)))
929 (message "Copied tar entry %s to %s" name to-file)))
931 (defun tar-flag-deleted (p &optional unflag)
932 "In Tar mode, mark this sub-file to be deleted from the tar file.
933 With a prefix argument, mark that many files."
937 (if (tar-current-descriptor unflag) ; barf if we're not on an entry-line.
940 (insert (if unflag " " "D"))))
941 (forward-line (if (< p 0) -1 1)))
942 (if (eobp) nil (forward-char 36)))
944 (defun tar-unflag (p)
945 "In Tar mode, un-mark this sub-file if it is marked to be deleted.
946 With a prefix argument, un-mark that many files forward."
948 (tar-flag-deleted p t))
950 (defun tar-unflag-backwards (p)
951 "In Tar mode, un-mark this sub-file if it is marked to be deleted.
952 With a prefix argument, un-mark that many files backward."
954 (tar-flag-deleted (- p) t))
957 (defun tar-expunge-internal ()
958 "Expunge the tar-entry specified by the current line."
959 (let ((descriptor (tar-current-descriptor)))
961 ;; delete the current line...
962 (delete-region (line-beginning-position) (line-beginning-position 2))
964 ;; delete the data pointer...
965 (setq tar-parse-info (delq descriptor tar-parse-info))
967 ;; delete the data from inside the file...
968 (with-current-buffer tar-data-buffer
969 (delete-region (or (tar-header-header-start descriptor)
970 (- (tar-header-data-start descriptor) 512))
971 (tar-header-data-end descriptor)))))
974 (defun tar-expunge (&optional noconfirm)
975 "In Tar mode, delete all the archived files flagged for deletion.
976 This does not modify the disk image; you must save the tar file itself
977 for this to be permanent."
980 (y-or-n-p "Expunge files marked for deletion? "))
983 (goto-char (point-min))
986 (progn (tar-expunge-internal)
989 ;; after doing the deletions, add any padding that may be necessary.
990 (tar-pad-to-blocksize))
992 (message "Nothing to expunge.")
993 (message "%s files expunged. Be sure to save this buffer." n)))))
996 (defun tar-clear-modification-flags ()
997 "Remove the stars at the beginning of each line."
1000 (goto-char (point-min))
1002 (if (not (eq (following-char) ?\s))
1003 (progn (delete-char 1) (insert " ")))
1007 (defun tar-chown-entry (new-uid)
1008 "Change the user-id associated with this entry in the tar file.
1009 If this tar file was written by GNU tar, then you will be able to edit
1010 the user id as a string; otherwise, you must edit it as a number.
1011 You can force editing as a number by calling this with a prefix arg.
1012 This does not modify the disk image; you must save the tar file itself
1013 for this to be permanent."
1016 (let ((descriptor (tar-current-descriptor)))
1017 (if (or current-prefix-arg
1018 (not (tar-header-magic descriptor)))
1021 (format "%s" (tar-header-uid descriptor)))
1022 (read-string "New UID string: " (tar-header-uname descriptor))))))
1023 (cond ((stringp new-uid)
1024 (setf (tar-header-uname (tar-current-descriptor)) new-uid)
1025 (tar-alter-one-field tar-uname-offset
1026 (concat (encode-coding-string
1027 new-uid tar-file-name-coding-system)
1030 (setf (tar-header-uid (tar-current-descriptor)) new-uid)
1031 (tar-alter-one-field tar-uid-offset
1032 (concat (substring (format "%6o" new-uid) 0 6) "\000 ")))))
1035 (defun tar-chgrp-entry (new-gid)
1036 "Change the group-id associated with this entry in the tar file.
1037 If this tar file was written by GNU tar, then you will be able to edit
1038 the group id as a string; otherwise, you must edit it as a number.
1039 You can force editing as a number by calling this with a prefix arg.
1040 This does not modify the disk image; you must save the tar file itself
1041 for this to be permanent."
1044 (let ((descriptor (tar-current-descriptor)))
1045 (if (or current-prefix-arg
1046 (not (tar-header-magic descriptor)))
1049 (format "%s" (tar-header-gid descriptor)))
1050 (read-string "New GID string: " (tar-header-gname descriptor))))))
1051 (cond ((stringp new-gid)
1052 (setf (tar-header-gname (tar-current-descriptor)) new-gid)
1053 (tar-alter-one-field tar-gname-offset
1054 (concat (encode-coding-string
1055 new-gid tar-file-name-coding-system)
1058 (setf (tar-header-gid (tar-current-descriptor)) new-gid)
1059 (tar-alter-one-field tar-gid-offset
1060 (concat (substring (format "%6o" new-gid) 0 6) "\000 ")))))
1062 (defun tar-rename-entry (new-name)
1063 "Change the name associated with this entry in the tar file.
1064 This does not modify the disk image; you must save the tar file itself
1065 for this to be permanent."
1067 (list (read-string "New name: "
1068 (tar-header-name (tar-current-descriptor)))))
1069 (if (string= "" new-name) (error "zero length name"))
1070 (let ((encoded-new-name (encode-coding-string new-name
1071 tar-file-name-coding-system))
1072 (descriptor (tar-current-descriptor))
1074 (when (tar-header-header-start descriptor)
1075 ;; FIXME: Make it work for ././@LongLink.
1076 (error "Rename with @LongLink format is not implemented"))
1078 (when (and (> (length encoded-new-name) 98)
1079 (string-match "/" encoded-new-name
1080 (- (length encoded-new-name) 99))
1081 (< (match-beginning 0) 155))
1082 (unless (equal (tar-header-magic descriptor) "ustar\0")
1083 (tar-alter-one-field tar-magic-offset (concat "ustar\0" "00")))
1084 (setq prefix (substring encoded-new-name 0 (match-beginning 0)))
1085 (setq encoded-new-name (substring encoded-new-name (match-end 0))))
1087 (if (> (length encoded-new-name) 98) (error "name too long"))
1088 (setf (tar-header-name descriptor) new-name)
1089 (tar-alter-one-field 0
1090 (substring (concat encoded-new-name (make-string 99 0)) 0 99))
1092 (tar-alter-one-field tar-prefix-offset
1093 (substring (concat prefix (make-string 155 0)) 0 155)))))
1096 (defun tar-chmod-entry (new-mode)
1097 "Change the protection bits associated with this entry in the tar file.
1098 This does not modify the disk image; you must save the tar file itself
1099 for this to be permanent."
1100 (interactive (list (tar-parse-octal-integer-safe
1101 (read-string "New protection (octal): "))))
1102 (setf (tar-header-mode (tar-current-descriptor)) new-mode)
1103 (tar-alter-one-field tar-mode-offset
1104 (concat (substring (format "%6o" new-mode) 0 6) "\000 ")))
1107 (defun tar-alter-one-field (data-position new-data-string &optional descriptor)
1108 (unless descriptor (setq descriptor (tar-current-descriptor)))
1110 ;; update the header-line.
1111 (let ((col (current-column)))
1112 (delete-region (line-beginning-position)
1113 (prog2 (forward-line 1)
1115 ;; Insert the new text after the old, before deleting,
1116 ;; to preserve markers such as the window start.
1117 (insert (tar-header-block-summarize descriptor) "\n")))
1118 (forward-line -1) (move-to-column col))
1120 (assert (tar-data-swapped-p))
1121 (with-current-buffer tar-data-buffer
1122 (let* ((start (- (tar-header-data-start descriptor) 512)))
1124 ;; delete the old field and insert a new one.
1125 (goto-char (+ start data-position))
1126 (delete-region (point) (+ (point) (length new-data-string))) ; <--
1127 (assert (not (or enable-multibyte-characters
1128 (multibyte-string-p new-data-string))))
1129 (insert new-data-string)
1131 ;; compute a new checksum and insert it.
1132 (let ((chk (tar-header-block-checksum
1133 (buffer-substring start (+ start 512)))))
1134 (goto-char (+ start tar-chk-offset))
1135 (delete-region (point) (+ (point) 8))
1136 (insert (format "%6o\0 " chk))
1137 (setf (tar-header-checksum descriptor) chk)
1139 ;; ok, make sure we didn't botch it.
1140 (tar-header-block-check-checksum
1141 (buffer-substring start (+ start 512))
1142 chk (tar-header-name descriptor))
1146 (defun tar-octal-time (timeval)
1147 ;; Format a timestamp as 11 octal digits. Ghod, I hope this works...
1148 (let ((hibits (car timeval)) (lobits (car (cdr timeval))))
1149 (format "%05o%01o%05o"
1151 (logior (lsh (logand 3 hibits) 1)
1152 (if (> (logand lobits 32768) 0) 1 0))
1153 (logand 32767 lobits)
1156 (defun tar-subfile-save-buffer ()
1157 "In tar subfile mode, save this buffer into its parent tar-file buffer.
1158 This doesn't write anything to disk; you must save the parent tar-file buffer
1159 to make your changes permanent."
1161 (if (not (and (boundp 'tar-superior-buffer) tar-superior-buffer))
1162 (error "This buffer has no superior tar file buffer"))
1163 (if (not (and (boundp 'tar-superior-descriptor) tar-superior-descriptor))
1164 (error "This buffer doesn't have an index into its superior tar file!"))
1165 (let ((subfile (current-buffer))
1166 (coding buffer-file-coding-system)
1167 (descriptor tar-superior-descriptor)
1169 (with-current-buffer tar-superior-buffer
1170 (let* ((start (tar-header-data-start descriptor))
1171 (name (tar-header-name descriptor))
1172 (size (tar-header-size descriptor))
1173 (head (memq descriptor tar-parse-info)))
1175 (error "Can't find this tar file entry in its parent tar file!"))
1176 (with-current-buffer tar-data-buffer
1177 ;; delete the old data...
1178 (let* ((data-start start)
1179 (data-end (+ data-start (tar-roundup-512 size))))
1180 (narrow-to-region data-start data-end)
1181 (delete-region (point-min) (point-max))
1182 ;; insert the new data...
1183 (goto-char data-start)
1184 (let ((dest (current-buffer)))
1185 (with-current-buffer subfile
1188 (encode-coding-region (point-min) (point-max) coding dest))))
1189 (setq subfile-size (- (point-max) (point-min)))
1191 ;; pad the new data out to a multiple of 512...
1192 (let ((subfile-size-pad (tar-roundup-512 subfile-size)))
1193 (goto-char (point-max))
1194 (insert (make-string (- subfile-size-pad subfile-size) 0))
1196 ;; update the data of this files...
1197 (setf (tar-header-size descriptor) subfile-size)
1199 ;; Update the size field in the header block.
1202 ;; alter the descriptor-line and header
1204 (let ((position (- (length tar-parse-info) (length head))))
1205 (goto-char (point-min))
1206 (forward-line position)
1207 (tar-alter-one-field tar-size-offset (format "%11o " subfile-size))
1209 ;; Maybe update the datestamp.
1210 (when tar-update-datestamp
1211 (tar-alter-one-field tar-time-offset
1212 (concat (tar-octal-time (current-time)) " "))))
1213 ;; After doing the insertion, add any necessary final padding.
1214 (tar-pad-to-blocksize))
1215 (set-buffer-modified-p t) ; mark the tar file as modified
1217 (set-buffer-modified-p nil) ; mark the tar subfile as unmodified
1218 (message "Saved into tar-buffer `%s'. Be sure to save that buffer!"
1219 (buffer-name tar-superior-buffer))
1220 ;; Prevent basic-save-buffer from changing our coding-system.
1221 (setq last-coding-system-used buffer-file-coding-system)
1222 ;; Prevent ordinary saving from happening.
1226 ;; When this function is called, it is sure that the buffer is unibyte.
1227 (defun tar-pad-to-blocksize ()
1228 "If we are being anal about tar file blocksizes, fix up the current buffer.
1229 Leaves the region wide."
1230 (if (null tar-anal-blocksize)
1232 (let* ((last-desc (nth (1- (length tar-parse-info)) tar-parse-info))
1233 (start (tar-header-data-start last-desc))
1234 (link-p (tar-header-link-type last-desc))
1235 (size (if link-p 0 (tar-header-size last-desc)))
1236 (data-end (+ start size))
1237 (bbytes (ash tar-anal-blocksize 9))
1238 (pad-to (+ bbytes (* bbytes (/ (- data-end (point-min)) bbytes)))))
1239 ;; If the padding after the last data is too long, delete some;
1240 ;; else insert some until we are padded out to the right number of blocks.
1242 (with-current-buffer tar-data-buffer
1243 (let ((goal-end (+ (point-min) pad-to)))
1244 (if (> (point-max) goal-end)
1245 (delete-region goal-end (point-max))
1246 (goto-char (point-max))
1247 (insert (make-string (- goal-end (point-max)) ?\0))))))))
1250 ;; Used in write-region-annotate-functions to write tar-files out correctly.
1251 (defun tar-write-region-annotate (start end)
1252 ;; When called from write-file (and auto-save), `start' is nil.
1253 ;; When called from M-x write-region, we assume the user wants to save
1254 ;; (part of) the summary, not the tar data.
1255 (unless (or start (not (tar-data-swapped-p)))
1256 (tar-clear-modification-flags)
1257 (set-buffer tar-data-buffer)
1262 ;; arch-tag: 8a585a4a-340e-42c2-89e7-d3b1013a4b78
1263 ;;; tar-mode.el ends here
HCoop / bpt / emacs.git / blob