1 ;;; tar-mode.el --- simple editing of tar files from GNU Emacs
3 ;; Copyright (C) 1990-1991, 1993-2012 Free Software Foundation, Inc.
5 ;; Author: Jamie Zawinski <jwz@lucid.com>
7 ;; Created: 04 Apr 1990
10 ;; This file is part of GNU Emacs.
12 ;; GNU Emacs is free software: you can redistribute it and/or modify
13 ;; it under the terms of the GNU General Public License as published by
14 ;; the Free Software Foundation, either version 3 of the License, or
15 ;; (at your option) any later version.
17 ;; GNU Emacs is distributed in the hope that it will be useful,
18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ;; GNU General Public License for more details.
22 ;; You should have received a copy of the GNU General Public License
23 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
27 ;; This package attempts to make dealing with Unix 'tar' archives easier.
28 ;; When this code is loaded, visiting a file whose name ends in '.tar' will
29 ;; cause the contents of that archive file to be displayed in a Dired-like
30 ;; listing. It is then possible to use the customary Dired keybindings to
31 ;; extract sub-files from that archive, either by reading them into their own
32 ;; editor buffers, or by copying them directly to arbitrary files on disk.
33 ;; It is also possible to delete sub-files from within the tar file and write
34 ;; the modified archive back to disk, or to edit sub-files within the archive
35 ;; and re-insert the modified files into the archive. See the documentation
36 ;; string of tar-mode for more info.
38 ;; This code now understands the extra fields that GNU tar adds to tar files.
40 ;; This interacts correctly with "uncompress.el" in the Emacs library,
43 ;; (autoload 'uncompress-while-visiting "uncompress")
44 ;; (setq auto-mode-alist (cons '("\\.Z$" . uncompress-while-visiting)
47 ;; Do not attempt to use tar-mode.el with crypt.el, you will lose.
49 ;; *************** TO DO ***************
51 ;; o chmod should understand "a+x,og-w".
53 ;; o It's not possible to add a NEW file to a tar archive; not that
54 ;; important, but still...
56 ;; o The code is less efficient that it could be - in a lot of places, I
57 ;; pull a 512-character string out of the buffer and parse it, when I could
58 ;; be parsing it in place, not garbaging a string. Should redo that.
60 ;; o I'd like a command that searches for a string/regexp in every subfile
61 ;; of an archive, where <esc> would leave you in a subfile-edit buffer.
62 ;; (Like the Meta-R command of the Zmacs mail reader.)
64 ;; o Sometimes (but not always) reverting the tar-file buffer does not
65 ;; re-grind the listing, and you are staring at the binary tar data.
66 ;; Typing 'g' again immediately after that will always revert and re-grind
67 ;; it, though. I have no idea why this happens.
69 ;; o Tar-mode interacts poorly with crypt.el and zcat.el because the tar
70 ;; write-file-hook actually writes the file. Instead it should remove the
71 ;; header (and conspire to put it back afterwards) so that other write-file
72 ;; hooks which frob the buffer have a chance to do their dirty work. There
73 ;; might be a problem if the tar write-file-hook does not come *first* on
76 ;; o Block files, sparse files, continuation files, and the various header
77 ;; types aren't editable. Actually I don't know that they work at all.
81 ;; Why does tar-mode edit the file itself instead of using tar?
83 ;; That means that you can edit tar files which you don't have room for
84 ;; on your local disk.
86 ;; I don't know about recent features in gnu tar, but old versions of tar
87 ;; can't replace a file in the middle of a tar file with a new version.
88 ;; Tar-mode can. I don't think tar can do things like chmod the subfiles.
89 ;; An implementation which involved unpacking and repacking the file into
90 ;; some scratch directory would be very wasteful, and wouldn't be able to
91 ;; preserve the file owners.
95 ;; - Rename on ././@LongLink files
96 ;; - Revert confirmation displays the raw data temporarily.
100 (eval-when-compile (require 'cl-lib
))
103 "Simple editing of tar files."
107 (defcustom tar-anal-blocksize
20
108 "The blocksize of tar files written by Emacs, or nil, meaning don't care.
109 The blocksize of a tar file is not really the size of the blocks; rather, it is
110 the number of blocks written with one system call. When tarring to a tape,
111 this is the size of the *tape* blocks, but when writing to a file, it doesn't
112 matter much. The only noticeable difference is that if a tar file does not
113 have a blocksize of 20, tar will tell you that; all this really controls is
114 how many null padding bytes go on the end of the tar file."
115 :type
'(choice integer
(const nil
))
118 (defcustom tar-update-datestamp nil
119 "Non-nil means Tar mode should play fast and loose with sub-file datestamps.
120 If this is true, then editing and saving a tar file entry back into its
121 tar file will update its datestamp. If false, the datestamp is unchanged.
122 You may or may not want this - it is good in that you can tell when a file
123 in a tar archive has been changed, but it is bad for the same reason that
124 editing a file in the tar archive at all is bad - the changed version of
125 the file never exists on disk."
129 (defcustom tar-mode-show-date nil
130 "Non-nil means Tar mode should show the date/time of each subfile.
131 This information is useful, but it takes screen space away from file names."
135 (defvar tar-parse-info nil
)
136 (defvar tar-superior-buffer nil
)
137 (defvar tar-superior-descriptor nil
)
138 (defvar tar-file-name-coding-system nil
)
140 (put 'tar-superior-buffer
'permanent-local t
)
141 (put 'tar-superior-descriptor
'permanent-local t
)
143 ;; The Tar data is made up of bytes and better manipulated as bytes
144 ;; and can be very large, so insert/delete can be costly. The summary we
145 ;; want to display may contain non-ascii chars, of course, so we'd like it
146 ;; to be multibyte. We used to keep both in the same buffer and switch
147 ;; from/to uni/multibyte. But this had several downsides:
148 ;; - set-buffer-multibyte has an O(N^2) worst case that tends to be triggered
149 ;; here, so it gets atrociously slow on large Tar files.
150 ;; - need to widen/narrow the buffer to show/hide the raw data, and need to
151 ;; maintain a tar-header-offset that keeps track of the boundary between
153 ;; - can't use markers because they're not preserved by set-buffer-multibyte.
154 ;; So instead, we now keep the two pieces of data in separate buffers, and
155 ;; use the new buffer-swap-text primitive when we need to change which data
156 ;; is associated with "the" buffer.
157 (defvar tar-data-buffer nil
"Buffer that holds the actual raw tar bytes.")
158 (make-variable-buffer-local 'tar-data-buffer
)
160 (defvar tar-data-swapped nil
161 "If non-nil, `tar-data-buffer' indeed holds raw tar bytes.")
162 (make-variable-buffer-local 'tar-data-swapped
)
164 (defun tar-data-swapped-p ()
165 "Return non-nil if the tar-data is in `tar-data-buffer'."
166 (and (buffer-live-p tar-data-buffer
)
167 ;; Sanity check to try and make sure tar-data-swapped tracks the swap
168 ;; state correctly: the raw data is expected to be always larger than
171 (cl-assert (or (= (buffer-size tar-data-buffer
) (buffer-size))
173 (> (buffer-size tar-data-buffer
) (buffer-size)))))
176 (defun tar-swap-data ()
177 "Swap buffer contents between current buffer and `tar-data-buffer'.
178 Preserve the modified states of the buffers and set `buffer-swapped-with'."
179 (let ((data-buffer-modified-p (buffer-modified-p tar-data-buffer
))
180 (current-buffer-modified-p (buffer-modified-p)))
181 (buffer-swap-text tar-data-buffer
)
182 (setq tar-data-swapped
(not tar-data-swapped
))
183 (restore-buffer-modified-p data-buffer-modified-p
)
184 (with-current-buffer tar-data-buffer
185 (restore-buffer-modified-p current-buffer-modified-p
))))
187 ;;; down to business.
189 (cl-defstruct (tar-header
194 make-tar-header
(data-start name mode uid gid size date checksum
195 link-type link-name magic uname gname dmaj dmin
)))
196 data-start name mode uid gid size date checksum link-type link-name
197 magic uname gname dmaj dmin
198 ;; Start of the header can be nil (meaning it's 512 bytes before data-start)
199 ;; or a marker (in case the header uses LongLink thingies).
202 (defconst tar-name-offset
0)
203 (defconst tar-mode-offset
(+ tar-name-offset
100))
204 (defconst tar-uid-offset
(+ tar-mode-offset
8))
205 (defconst tar-gid-offset
(+ tar-uid-offset
8))
206 (defconst tar-size-offset
(+ tar-gid-offset
8))
207 (defconst tar-time-offset
(+ tar-size-offset
12))
208 (defconst tar-chk-offset
(+ tar-time-offset
12))
209 (defconst tar-linkp-offset
(+ tar-chk-offset
8))
210 (defconst tar-link-offset
(+ tar-linkp-offset
1))
211 ;;; GNU-tar specific slots.
212 (defconst tar-magic-offset
(+ tar-link-offset
100))
213 (defconst tar-uname-offset
(+ tar-magic-offset
8))
214 (defconst tar-gname-offset
(+ tar-uname-offset
32))
215 (defconst tar-dmaj-offset
(+ tar-gname-offset
32))
216 (defconst tar-dmin-offset
(+ tar-dmaj-offset
8))
217 (defconst tar-prefix-offset
(+ tar-dmin-offset
8))
218 (defconst tar-end-offset
(+ tar-prefix-offset
155))
220 (defun tar-roundup-512 (s)
221 "Round S up to the next multiple of 512."
222 (ash (ash (+ s
511) -
9) 9))
224 (defun tar-header-block-tokenize (pos coding
)
225 "Return a `tar-header' structure.
226 This is a list of name, mode, uid, gid, size,
227 write-date, checksum, link-type, and link-name."
228 (if (> (+ pos
512) (point-max)) (error "Malformed Tar header"))
229 (cl-assert (zerop (mod (- pos
(point-min)) 512)))
230 (cl-assert (not enable-multibyte-characters
))
231 (let ((string (buffer-substring pos
(setq pos
(+ pos
512)))))
232 (when ;(some 'plusp string) ; <-- oops, massive cycle hog!
233 (or (not (= 0 (aref string
0))) ; This will do.
234 (not (= 0 (aref string
101))))
235 (let* ((name-end tar-mode-offset
)
236 (link-end (1- tar-magic-offset
))
237 (uname-end (1- tar-gname-offset
))
238 (gname-end (1- tar-dmaj-offset
))
239 (link-p (aref string tar-linkp-offset
))
240 (magic-str (substring string tar-magic-offset
241 ;; The magic string is actually 6bytes
242 ;; of magic string plus 2bytes of version
243 ;; which we here ignore.
244 (- tar-uname-offset
2)))
245 ;; The magic string is "ustar\0" for POSIX format, and
246 ;; "ustar " for GNU Tar's format.
247 (uname-valid-p (car (member magic-str
'("ustar " "ustar\0"))))
249 (nulsexp "[^\000]*\000"))
250 (when (string-match nulsexp string tar-name-offset
)
251 (setq name-end
(min name-end
(1- (match-end 0)))))
252 (when (string-match nulsexp string tar-link-offset
)
253 (setq link-end
(min link-end
(1- (match-end 0)))))
254 (when (string-match nulsexp string tar-uname-offset
)
255 (setq uname-end
(min uname-end
(1- (match-end 0)))))
256 (when (string-match nulsexp string tar-gname-offset
)
257 (setq gname-end
(min gname-end
(1- (match-end 0)))))
258 (setq name
(substring string tar-name-offset name-end
)
259 link-p
(if (or (= link-p
0) (= link-p ?
0))
262 (setq linkname
(substring string tar-link-offset link-end
))
263 (when (and (equal uname-valid-p
"ustar\0")
264 (string-match nulsexp string tar-prefix-offset
)
265 (> (match-end 0) (1+ tar-prefix-offset
)))
266 (setq name
(concat (substring string tar-prefix-offset
269 (if (default-value 'enable-multibyte-characters
)
271 (decode-coding-string name coding
)
273 (decode-coding-string linkname coding
)))
274 (if (and (null link-p
) (string-match "/\\'" name
))
275 (setq link-p
5)) ; directory
277 (if (and (equal name
"././@LongLink")
278 ;; Supposedly @LongLink is only used for GNUTAR
279 ;; format (i.e. "ustar ") but some POSIX Tar files
280 ;; (with "ustar\0") have been seen using it as well.
281 (member magic-str
'("ustar " "ustar\0")))
282 ;; This is a GNU Tar long-file-name header.
283 (let* ((size (tar-parse-octal-integer
284 string tar-size-offset tar-time-offset
))
285 ;; -1 so as to strip the terminating 0 byte.
286 (name (decode-coding-string
287 (buffer-substring pos
(+ pos size -
1)) coding
))
288 (descriptor (tar-header-block-tokenize
289 (+ pos
(tar-roundup-512 size
))
292 ((eq link-p
(- ?L ?
0)) ;GNUTYPE_LONGNAME.
293 (setf (tar-header-name descriptor
) name
))
294 ((eq link-p
(- ?K ?
0)) ;GNUTYPE_LONGLINK.
295 (setf (tar-header-link-name descriptor
) name
))
297 (message "Unrecognized GNU Tar @LongLink format")))
298 (setf (tar-header-header-start descriptor
)
299 (copy-marker (- pos
512) t
))
303 (copy-marker pos nil
)
305 (tar-parse-octal-integer string tar-mode-offset tar-uid-offset
)
306 (tar-parse-octal-integer string tar-uid-offset tar-gid-offset
)
307 (tar-parse-octal-integer string tar-gid-offset tar-size-offset
)
308 (tar-parse-octal-integer string tar-size-offset tar-time-offset
)
309 (tar-parse-octal-long-integer string tar-time-offset tar-chk-offset
)
310 (tar-parse-octal-integer string tar-chk-offset tar-linkp-offset
)
315 (decode-coding-string
316 (substring string tar-uname-offset uname-end
) coding
))
318 (decode-coding-string
319 (substring string tar-gname-offset gname-end
) coding
))
320 (tar-parse-octal-integer string tar-dmaj-offset tar-dmin-offset
)
321 (tar-parse-octal-integer string tar-dmin-offset tar-prefix-offset
)
325 (defun tar-header-data-end (descriptor)
326 (let* ((data-start (tar-header-data-start descriptor
))
327 (link-type (tar-header-link-type descriptor
))
328 (size (tar-header-size descriptor
)))
330 ;; Ignore size for files of type 1-6
331 (if (and (not (memq link-type
'(1 2 3 4 5 6))) (> size
0))
332 (tar-roundup-512 size
)
335 (defun tar-parse-octal-integer (string &optional start end
)
336 (if (null start
) (setq start
0))
337 (if (null end
) (setq end
(length string
)))
338 (if (= (aref string start
) 0)
342 (setq n
(if (< (aref string start
) ?
0) n
343 (+ (* n
8) (- (aref string start
) ?
0)))
347 (defun tar-parse-octal-long-integer (string &optional start end
)
348 (if (null start
) (setq start
0))
349 (if (null end
) (setq end
(length string
)))
350 (if (= (aref string start
) 0)
355 (if (>= (aref string start
) ?
0)
356 (setq lo
(+ (* lo
8) (- (aref string start
) ?
0))
357 hi
(+ (* hi
8) (ash lo -
16))
358 lo
(logand lo
65535)))
359 (setq start
(1+ start
)))
362 (defun tar-parse-octal-integer-safe (string)
363 (if (zerop (length string
)) (error "empty string"))
365 (if (or (< c ?
0) (> c ?
7))
366 (error "`%c' is not an octal digit" c
)))
368 (tar-parse-octal-integer string
))
371 (defun tar-header-block-checksum (string)
372 "Compute and return a tar-acceptable checksum for this block."
373 (cl-assert (not (multibyte-string-p string
)))
374 (let* ((chk-field-start tar-chk-offset
)
375 (chk-field-end (+ chk-field-start
8))
378 ;; Add up all of the characters except the ones in the checksum field.
379 ;; Add that field as if it were filled with spaces.
380 (while (< i chk-field-start
)
381 (setq sum
(+ sum
(aref string i
))
383 (setq i chk-field-end
)
385 (setq sum
(+ sum
(aref string i
))
389 (defun tar-header-block-check-checksum (hblock desired-checksum file-name
)
390 "Beep and print a warning if the checksum doesn't match."
391 (if (not (= desired-checksum
(tar-header-block-checksum hblock
)))
392 (progn (beep) (message "Invalid checksum for file %s!" file-name
))))
394 (defun tar-clip-time-string (time)
395 (let ((str (current-time-string time
)))
396 (concat " " (substring str
4 16) (format-time-string " %Y" time
))))
398 (defun tar-grind-file-mode (mode)
399 "Construct a `-rw--r--r--' string indicating MODE.
400 MODE should be an integer which is a file mode value."
402 (if (zerop (logand 256 mode
)) ?- ?r
)
403 (if (zerop (logand 128 mode
)) ?- ?w
)
404 (if (zerop (logand 2048 mode
))
405 (if (zerop (logand 64 mode
)) ?- ?x
)
406 (if (zerop (logand 64 mode
)) ?S ?s
))
407 (if (zerop (logand 32 mode
)) ?- ?r
)
408 (if (zerop (logand 16 mode
)) ?- ?w
)
409 (if (zerop (logand 1024 mode
))
410 (if (zerop (logand 8 mode
)) ?- ?x
)
411 (if (zerop (logand 8 mode
)) ?S ?s
))
412 (if (zerop (logand 4 mode
)) ?- ?r
)
413 (if (zerop (logand 2 mode
)) ?- ?w
)
414 (if (zerop (logand 512 mode
))
415 (if (zerop (logand 1 mode
)) ?- ?x
)
416 (if (zerop (logand 1 mode
)) ?T ?t
))))
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
) ; pax global extended header
446 ((eq type
72) ?X
) ; pax extended header
449 (tar-grind-file-mode mode
)
450 (if (= 0 (length uname
)) uid uname
)
451 (if (= 0 (length gname
)) gid gname
)
453 (if tar-mode-show-date
(tar-clip-time-string time
) "")
455 'mouse-face
'highlight
456 'help-echo
"mouse-2: extract this file into a buffer")
457 (if (or (eq type
1) (eq type
2))
458 (concat (if (= type
1) " ==> " " --> ") link-name
)
461 (defun tar-untar-buffer ()
462 "Extract all archive members in the tar-file into the current directory."
464 ;; FIXME: make it work even if we're not in tar-mode.
465 (let ((descriptors tar-parse-info
)) ;Read the var in its buffer.
467 (if (tar-data-swapped-p) tar-data-buffer
(current-buffer))
468 (set-buffer-multibyte nil
) ;Hopefully, a no-op.
469 (dolist (descriptor descriptors
)
470 (let* ((name (tar-header-name descriptor
))
471 (dir (if (eq (tar-header-link-type descriptor
) 5)
473 (file-name-directory name
)))
474 (start (tar-header-data-start descriptor
))
475 (end (+ start
(tar-header-size descriptor
))))
476 (unless (file-directory-p name
)
477 (message "Extracting %s" name
)
478 (if (and dir
(not (file-exists-p dir
)))
479 (make-directory dir t
))
480 (unless (file-directory-p name
)
481 (let ((coding-system-for-write 'no-conversion
))
482 (write-region start end name
)))
483 (set-file-modes name
(tar-header-mode descriptor
))))))))
485 (defun tar-summarize-buffer ()
486 "Parse the contents of the tar file in the current buffer."
487 (cl-assert (tar-data-swapped-p))
488 (let* ((modified (buffer-modified-p))
491 (coding tar-file-name-coding-system
)
493 (with-current-buffer tar-data-buffer
494 (make-progress-reporter "Parsing tar file..."
495 (point-min) (point-max))))
497 (with-current-buffer tar-data-buffer
498 (while (and (< pos
(point-max))
499 (setq descriptor
(tar-header-block-tokenize pos coding
)))
500 (let ((size (tar-header-size descriptor
)))
502 (error "%s has size %s - corrupted"
503 (tar-header-name descriptor
) size
)))
505 ;; This is just too slow. Don't really need it anyway....
506 ;;(tar-header-block-check-checksum
507 ;; hblock (tar-header-block-checksum hblock)
508 ;; (tar-header-name descriptor))
510 (push descriptor result
)
511 (setq pos
(tar-header-data-end descriptor
))
512 (progress-reporter-update progress-reporter pos
)))
514 (set (make-local-variable 'tar-parse-info
) (nreverse result
))
515 ;; A tar file should end with a block or two of nulls,
516 ;; but let's not get a fatal error if it doesn't.
517 (if (null descriptor
)
518 (progress-reporter-done progress-reporter
)
519 (message "Warning: premature EOF parsing tar file"))
520 (goto-char (point-min))
521 (let ((inhibit-read-only t
)
523 (mapconcat 'tar-header-block-summarize tar-parse-info
"\n")))
524 (insert total-summaries
"\n"))
525 (goto-char (point-min))
526 (restore-buffer-modified-p modified
)))
529 (let ((map (make-keymap)))
530 (suppress-keymap map
)
531 (define-key map
" " 'tar-next-line
)
532 (define-key map
"C" 'tar-copy
)
533 (define-key map
"d" 'tar-flag-deleted
)
534 (define-key map
"\^D" 'tar-flag-deleted
)
535 (define-key map
"e" 'tar-extract
)
536 (define-key map
"f" 'tar-extract
)
537 (define-key map
"\C-m" 'tar-extract
)
538 (define-key map
[mouse-2
] 'tar-mouse-extract
)
539 (define-key map
"g" 'revert-buffer
)
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 "\^P" 'tar-previous-line)
546 (define-key map [up] 'tar-previous-line)
547 (define-key map "R" 'tar-rename-entry)
548 (define-key map "u" 'tar-unflag)
549 (define-key map "v" 'tar-view)
550 (define-key map "w" 'woman-tar-extract-file)
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 woman]
569 '("Read Man Page (WoMan)" . woman-tar-extract-file))
570 (define-key map [menu-bar immediate view]
571 '("View This File" . tar-view))
572 (define-key map [menu-bar immediate display]
573 '("Display in Other Window" . tar-display-other-window))
574 (define-key map [menu-bar immediate find-file-other-window]
575 '("Find in Other Window" . tar-extract-other-window))
576 (define-key map [menu-bar immediate find-file]
577 '("Find This File" . tar-extract))
579 (define-key map [menu-bar mark]
580 (cons "Mark" (make-sparse-keymap "Mark")))
582 (define-key map [menu-bar mark unmark-all]
583 '("Unmark All" . tar-clear-modification-flags))
584 (define-key map [menu-bar mark deletion]
585 '("Flag" . tar-flag-deleted))
586 (define-key map [menu-bar mark unmark]
587 '("Unflag" . tar-unflag))
589 (define-key map [menu-bar operate]
590 (cons "Operate" (make-sparse-keymap "Operate")))
592 (define-key map [menu-bar operate chown]
593 '("Change Owner..." . tar-chown-entry))
594 (define-key map [menu-bar operate chgrp]
595 '("Change Group..." . tar-chgrp-entry))
596 (define-key map [menu-bar operate chmod]
597 '("Change Mode..." . tar-chmod-entry))
598 (define-key map [menu-bar operate rename]
599 '("Rename to..." . tar-rename-entry))
600 (define-key map [menu-bar operate copy]
601 '("Copy to..." . tar-copy))
602 (define-key map [menu-bar operate expunge]
603 '("Expunge Marked Files" . tar-expunge))
606 "Local keymap for Tar mode listings.")
609 ;; tar mode is suitable only for specially formatted data.
610 (put 'tar-mode 'mode-class 'special)
611 (put 'tar-subfile-mode 'mode-class 'special)
613 (defun tar-change-major-mode-hook ()
614 ;; Bring the actual Tar data back into the main buffer.
615 (when (tar-data-swapped-p) (tar-swap-data))
616 ;; Throw away the summary.
617 (when (buffer-live-p tar-data-buffer) (kill-buffer tar-data-buffer)))
619 (defun tar-mode-kill-buffer-hook ()
620 (if (buffer-live-p tar-data-buffer) (kill-buffer tar-data-buffer)))
623 (define-derived-mode tar-mode special-mode "Tar"
624 "Major mode for viewing a tar file as a dired-like listing of its contents.
625 You can move around using the usual cursor motion commands.
626 Letters no longer insert themselves.
627 Type `e' to pull a file out of the tar file and into its own buffer;
628 or click mouse-2 on the file's line in the Tar mode buffer.
629 Type `c' to copy an entry from the tar file into another file on disk.
631 If you edit a sub-file of this archive (as with the `e' command) and
632 save it with \\[save-buffer], the contents of that buffer will be
633 saved back into the tar-file buffer; in this way you can edit a file
634 inside of a tar archive without extracting it and re-archiving it.
636 See also: variables `tar-update-datestamp' and `tar-anal-blocksize'.
638 (and buffer-file-name
639 (file-writable-p buffer-file-name)
640 (setq buffer-read-only nil)) ; undo what `special-mode' did
641 (make-local-variable 'tar-parse-info)
642 (set (make-local-variable 'require-final-newline) nil) ; binary data, dude...
643 (set (make-local-variable 'local-enable-local-variables) nil)
644 (set (make-local-variable 'next-line-add-newlines) nil)
645 (set (make-local-variable 'tar-file-name-coding-system)
646 (or file-name-coding-system
647 default-file-name-coding-system
648 locale-coding-system))
649 ;; Prevent loss of data when saving the file.
650 (set (make-local-variable 'file-precious-flag) t)
651 (buffer-disable-undo)
653 ;; Now move the Tar data into an auxiliary buffer, so we can use the main
654 ;; buffer for the summary.
655 (cl-assert (not (tar-data-swapped-p)))
656 (set (make-local-variable 'revert-buffer-function) 'tar-mode-revert)
657 ;; We started using write-contents-functions, but this hook is not
658 ;; used during auto-save, so we now use
659 ;; write-region-annotate-functions which hooks at a lower-level.
660 (add-hook 'write-region-annotate-functions 'tar-write-region-annotate nil t)
661 (add-hook 'kill-buffer-hook 'tar-mode-kill-buffer-hook nil t)
662 (add-hook 'change-major-mode-hook 'tar-change-major-mode-hook nil t)
663 ;; Tar data is made of bytes, not chars.
664 (set-buffer-multibyte nil) ;Hopefully a no-op.
665 (set (make-local-variable 'tar-data-buffer)
666 (generate-new-buffer (format " *tar-data %s*"
667 (file-name-nondirectory
668 (or buffer-file-name (buffer-name))))))
672 (tar-summarize-buffer)
675 ;; If summarizing caused an error, then maybe the buffer doesn't contain
676 ;; tar data. Rather than show a mysterious empty buffer, let's
677 ;; revert to fundamental-mode.
679 (signal (car err) (cdr err)))))
681 (autoload 'woman-tar-extract-file "woman"
682 "In tar mode, run the WoMan man-page browser on this file." t)
684 (define-minor-mode tar-subfile-mode
685 "Minor mode for editing an element of a tar-file.
686 With a prefix argument ARG, enable the mode if ARG is positive,
687 and disable it otherwise. If called from Lisp, enable the mode
688 if ARG is omitted or nil. This mode arranges for \"saving\" this
689 buffer to write the data into the tar-file buffer that it came
690 from. The changes will actually appear on disk when you save the
692 ;; Don't do this, because it is redundant and wastes mode line space.
693 ;; :lighter " TarFile"
695 (or (and (boundp 'tar-superior-buffer) tar-superior-buffer)
696 (error "This buffer is not an element of a tar file"))
697 (cond (tar-subfile-mode
698 (add-hook 'write-file-functions 'tar-subfile-save-buffer nil t)
699 ;; turn off auto-save.
701 (setq buffer-auto-save-file-name nil))
703 (remove-hook 'write-file-functions 'tar-subfile-save-buffer t))))
706 ;; Revert the buffer and recompute the dired-like listing.
707 (defun tar-mode-revert (&optional no-auto-save no-confirm)
709 (let ((revert-buffer-function nil))
710 (if (tar-data-swapped-p) (tar-swap-data))
711 ;; FIXME: If we ask for confirmation, the user will be temporarily
712 ;; looking at the raw data.
713 (revert-buffer no-auto-save no-confirm 'preserve-modes)
714 ;; Recompute the summary.
715 (if (buffer-live-p tar-data-buffer) (kill-buffer tar-data-buffer))
717 (unless (tar-data-swapped-p) (tar-swap-data))))
720 (defun tar-next-line (arg)
721 "Move cursor vertically down ARG lines and to the start of the filename."
724 (goto-char (or (next-single-property-change (point) 'mouse-face) (point))))
726 (defun tar-previous-line (arg)
727 "Move cursor vertically up ARG lines and to the start of the filename."
729 (tar-next-line (- arg)))
731 (defun tar-current-descriptor (&optional noerror)
732 "Return the tar-descriptor of the current line, or signals an error."
733 ;; I wish lines had plists, like in ZMACS...
734 (or (nth (count-lines (point-min) (line-beginning-position))
738 (error "This line does not describe a tar-file entry"))))
740 (defun tar-get-descriptor ()
741 (let* ((descriptor (tar-current-descriptor))
742 (size (tar-header-size descriptor))
743 (link-p (tar-header-link-type descriptor)))
745 (error "This is %s, not a real file"
746 (cond ((eq link-p 5) "a directory")
747 ((eq link-p 20) "a tar directory header")
748 ((eq link-p 28) "a next has longname")
749 ((eq link-p 29) "a multivolume-continuation")
750 ((eq link-p 35) "a sparse entry")
751 ((eq link-p 38) "a volume header")
752 ((eq link-p 55) "a pax global extended header")
753 ((eq link-p 72) "a pax extended header")
755 (if (zerop size) (message "This is a zero-length file"))
758 (defun tar-mouse-extract (event)
759 "Extract a file whose tar directory line you click on."
761 (with-current-buffer (window-buffer (posn-window (event-end event)))
763 (goto-char (posn-point (event-end event)))
764 ;; Just make sure this doesn't get an error.
765 (tar-get-descriptor)))
766 (select-window (posn-window (event-end event)))
767 (goto-char (posn-point (event-end event)))
770 (defun tar-file-name-handler (op &rest args)
771 "Helper function for `tar-extract'."
772 (or (eq op 'file-exists-p)
773 (let ((file-name-handler-alist nil))
776 (defun tar-extract (&optional other-window-p)
777 "In Tar mode, extract this entry of the tar file into its own buffer."
779 (let* ((view-p (eq other-window-p 'view))
780 (descriptor (tar-get-descriptor))
781 (name (tar-header-name descriptor))
782 (size (tar-header-size descriptor))
783 (start (tar-header-data-start descriptor))
784 (end (+ start size)))
785 (let* ((tar-buffer (current-buffer))
786 (tarname (buffer-name))
787 (bufname (concat (file-name-nondirectory name)
791 (read-only-p (or buffer-read-only view-p))
792 (new-buffer-file-name (expand-file-name
793 ;; `:' is not allowed on Windows
795 (if (string-match "/" name)
797 ;; Make sure `name' contains a /
798 ;; so set-auto-mode doesn't try
799 ;; to look at `tarname' for hints.
800 (concat "./" name)))))
801 (buffer (get-file-buffer new-buffer-file-name))
805 (setq buffer (generate-new-buffer bufname))
806 (with-current-buffer buffer
807 (setq undo-list buffer-undo-list
809 (setq bufname (buffer-name buffer))
810 (setq just-created t)
811 (with-current-buffer tar-data-buffer
813 (narrow-to-region start end)
815 (setq coding (or coding-system-for-read
816 (and set-auto-coding-function
817 (funcall set-auto-coding-function
819 ;; The following binding causes
820 ;; find-buffer-file-type-coding-system
821 ;; (defined on dos-w32.el) to act as if
822 ;; the file being extracted existed, so
823 ;; that the file's contents' encoding and
824 ;; EOL format are auto-detected.
825 (let ((file-name-handler-alist
826 '(("" . tar-file-name-handler))))
827 (car (find-operation-coding-system
828 'insert-file-contents
829 (cons name (current-buffer)) t)))))
831 (eq (coding-system-type coding) 'undecided))
832 (setq coding (detect-coding-region start end t)))
833 (if (and (default-value 'enable-multibyte-characters)
834 (coding-system-get coding :for-unibyte))
835 (with-current-buffer buffer
836 (set-buffer-multibyte nil)))
838 (decode-coding-region start end coding buffer)))
839 (with-current-buffer buffer
840 (goto-char (point-min))
841 (setq buffer-file-name new-buffer-file-name)
842 (setq buffer-file-truename
843 (abbreviate-file-name buffer-file-name))
844 ;; Force buffer-file-coding-system to what
845 ;; decode-coding-region actually used.
846 (set-buffer-file-coding-system last-coding-system-used t)
847 ;; Set the default-directory to the dir of the
849 (setq default-directory
850 (with-current-buffer tar-buffer
852 (rename-buffer bufname)
853 (set-buffer-modified-p nil)
854 (setq buffer-undo-list undo-list)
855 (normal-mode) ; pick a mode.
856 (set (make-local-variable 'tar-superior-buffer) tar-buffer)
857 (set (make-local-variable 'tar-superior-descriptor) descriptor)
858 (setq buffer-read-only read-only-p)
859 (tar-subfile-mode 1)))
862 (view-buffer buffer (and just-created 'kill-buffer-if-not-modified)))
863 ((eq other-window-p 'display) (display-buffer buffer))
864 (other-window-p (switch-to-buffer-other-window buffer))
865 (t (switch-to-buffer buffer))))))
868 (defun tar-extract-other-window ()
869 "In Tar mode, find this entry of the tar file in another window."
873 (defun tar-display-other-window ()
874 "In Tar mode, display this entry of the tar file in another window."
876 (tar-extract 'display))
879 "In Tar mode, view the tar file entry on this line."
884 (defun tar-read-file-name (&optional prompt)
885 "Read a file name with this line's entry as the default."
886 (or prompt (setq prompt "Copy to: "))
887 (let* ((default-file (expand-file-name
888 (tar-header-name (tar-current-descriptor))))
889 (target (expand-file-name
890 (read-file-name prompt
891 (file-name-directory default-file)
893 (if (or (string= "" (file-name-nondirectory target))
894 (file-directory-p target))
895 (setq target (concat (if (string-match "/$" target)
896 (substring target 0 (1- (match-end 0)))
899 (file-name-nondirectory default-file))))
903 (defun tar-copy (&optional to-file)
904 "In Tar mode, extract this entry of the tar file into a file on disk.
905 If TO-FILE is not supplied, it is prompted for, defaulting to the name of
906 the current tar-entry."
907 (interactive (list (tar-read-file-name)))
908 (let* ((descriptor (tar-get-descriptor))
909 (name (tar-header-name descriptor))
910 (size (tar-header-size descriptor))
911 (start (tar-header-data-start descriptor))
913 (inhibit-file-name-handlers inhibit-file-name-handlers)
914 (inhibit-file-name-operation inhibit-file-name-operation))
916 (if (tar-data-swapped-p) tar-data-buffer (current-buffer))
917 ;; Inhibit compressing a subfile again if *both* name and
918 ;; to-file are handled by jka-compr
919 (if (and (eq (find-file-name-handler name 'write-region)
921 (eq (find-file-name-handler to-file 'write-region)
923 (setq inhibit-file-name-handlers
924 (cons 'jka-compr-handler
925 (and (eq inhibit-file-name-operation 'write-region)
926 inhibit-file-name-handlers))
927 inhibit-file-name-operation 'write-region))
928 (let ((coding-system-for-write 'no-conversion))
929 (write-region start end to-file nil nil nil t)))
930 (message "Copied tar entry %s to %s" name to-file)))
932 (defun tar-flag-deleted (p &optional unflag)
933 "In Tar mode, mark this sub-file to be deleted from the tar file.
934 With a prefix argument, mark that many files."
938 (if (tar-current-descriptor unflag) ; barf if we're not on an entry-line.
941 (insert (if unflag " " "D"))))
942 (forward-line (if (< p 0) -1 1)))
943 (if (eobp) nil (forward-char 36)))
945 (defun tar-unflag (p)
946 "In Tar mode, un-mark this sub-file if it is marked to be deleted.
947 With a prefix argument, un-mark that many files forward."
949 (tar-flag-deleted p t))
951 (defun tar-unflag-backwards (p)
952 "In Tar mode, un-mark this sub-file if it is marked to be deleted.
953 With a prefix argument, un-mark that many files backward."
955 (tar-flag-deleted (- p) t))
958 (defun tar-expunge-internal ()
959 "Expunge the tar-entry specified by the current line."
960 (let ((descriptor (tar-current-descriptor)))
962 ;; delete the current line...
963 (delete-region (line-beginning-position) (line-beginning-position 2))
965 ;; delete the data pointer...
966 (setq tar-parse-info (delq descriptor tar-parse-info))
968 ;; delete the data from inside the file...
969 (with-current-buffer tar-data-buffer
970 (delete-region (or (tar-header-header-start descriptor)
971 (- (tar-header-data-start descriptor) 512))
972 (tar-header-data-end descriptor)))))
975 (defun tar-expunge (&optional noconfirm)
976 "In Tar mode, delete all the archived files flagged for deletion.
977 This does not modify the disk image; you must save the tar file itself
978 for this to be permanent."
981 (y-or-n-p "Expunge files marked for deletion? "))
984 (goto-char (point-min))
987 (progn (tar-expunge-internal)
990 ;; after doing the deletions, add any padding that may be necessary.
991 (tar-pad-to-blocksize))
993 (message "Nothing to expunge.")
994 (message "%s files expunged. Be sure to save this buffer." n)))))
997 (defun tar-clear-modification-flags ()
998 "Remove the stars at the beginning of each line."
1001 (goto-char (point-min))
1003 (if (not (eq (following-char) ?\s))
1004 (progn (delete-char 1) (insert " ")))
1008 (defun tar-chown-entry (new-uid)
1009 "Change the user-id associated with this entry in the tar file.
1010 If this tar file was written by GNU tar, then you will be able to edit
1011 the user id as a string; otherwise, you must edit it as a number.
1012 You can force editing as a number by calling this with a prefix arg.
1013 This does not modify the disk image; you must save the tar file itself
1014 for this to be permanent."
1017 (let ((descriptor (tar-current-descriptor)))
1018 (if (or current-prefix-arg
1019 (not (tar-header-magic descriptor)))
1022 (format "%s" (tar-header-uid descriptor)))
1023 (read-string "New UID string: " (tar-header-uname descriptor))))))
1024 (cond ((stringp new-uid)
1025 (setf (tar-header-uname (tar-current-descriptor)) new-uid)
1026 (tar-alter-one-field tar-uname-offset
1027 (concat (encode-coding-string
1028 new-uid tar-file-name-coding-system)
1031 (setf (tar-header-uid (tar-current-descriptor)) new-uid)
1032 (tar-alter-one-field tar-uid-offset
1033 (concat (substring (format "%6o" new-uid) 0 6) "\000 ")))))
1036 (defun tar-chgrp-entry (new-gid)
1037 "Change the group-id associated with this entry in the tar file.
1038 If this tar file was written by GNU tar, then you will be able to edit
1039 the group id as a string; otherwise, you must edit it as a number.
1040 You can force editing as a number by calling this with a prefix arg.
1041 This does not modify the disk image; you must save the tar file itself
1042 for this to be permanent."
1045 (let ((descriptor (tar-current-descriptor)))
1046 (if (or current-prefix-arg
1047 (not (tar-header-magic descriptor)))
1050 (format "%s" (tar-header-gid descriptor)))
1051 (read-string "New GID string: " (tar-header-gname descriptor))))))
1052 (cond ((stringp new-gid)
1053 (setf (tar-header-gname (tar-current-descriptor)) new-gid)
1054 (tar-alter-one-field tar-gname-offset
1055 (concat (encode-coding-string
1056 new-gid tar-file-name-coding-system)
1059 (setf (tar-header-gid (tar-current-descriptor)) new-gid)
1060 (tar-alter-one-field tar-gid-offset
1061 (concat (substring (format "%6o" new-gid) 0 6) "\000 ")))))
1063 (defun tar-rename-entry (new-name)
1064 "Change the name associated with this entry in the tar file.
1065 This does not modify the disk image; you must save the tar file itself
1066 for this to be permanent."
1068 (list (read-string "New name: "
1069 (tar-header-name (tar-current-descriptor)))))
1070 (if (string= "" new-name) (error "zero length name"))
1071 (let ((encoded-new-name (encode-coding-string new-name
1072 tar-file-name-coding-system))
1073 (descriptor (tar-current-descriptor))
1075 (when (tar-header-header-start descriptor)
1076 ;; FIXME: Make it work for ././@LongLink.
1077 (error "Rename with @LongLink format is not implemented"))
1079 (when (and (> (length encoded-new-name) 98)
1080 (string-match "/" encoded-new-name
1081 (- (length encoded-new-name) 99))
1082 (< (match-beginning 0) 155))
1083 (unless (equal (tar-header-magic descriptor) "ustar\0")
1084 (tar-alter-one-field tar-magic-offset (concat "ustar\0" "00")))
1085 (setq prefix (substring encoded-new-name 0 (match-beginning 0)))
1086 (setq encoded-new-name (substring encoded-new-name (match-end 0))))
1088 (if (> (length encoded-new-name) 98) (error "name too long"))
1089 (setf (tar-header-name descriptor) new-name)
1090 (tar-alter-one-field 0
1091 (substring (concat encoded-new-name (make-string 99 0)) 0 99))
1093 (tar-alter-one-field tar-prefix-offset
1094 (substring (concat prefix (make-string 155 0)) 0 155)))))
1097 (defun tar-chmod-entry (new-mode)
1098 "Change the protection bits associated with this entry in the tar file.
1099 This does not modify the disk image; you must save the tar file itself
1100 for this to be permanent."
1101 (interactive (list (tar-parse-octal-integer-safe
1102 (read-string "New protection (octal): "))))
1103 (setf (tar-header-mode (tar-current-descriptor)) new-mode)
1104 (tar-alter-one-field tar-mode-offset
1105 (concat (substring (format "%6o" new-mode) 0 6) "\000 ")))
1108 (defun tar-alter-one-field (data-position new-data-string &optional descriptor)
1109 (unless descriptor (setq descriptor (tar-current-descriptor)))
1111 ;; update the header-line.
1112 (let ((col (current-column)))
1113 (delete-region (line-beginning-position)
1114 (prog2 (forward-line 1)
1116 ;; Insert the new text after the old, before deleting,
1117 ;; to preserve markers such as the window start.
1118 (insert (tar-header-block-summarize descriptor) "\n")))
1119 (forward-line -1) (move-to-column col))
1121 (cl-assert (tar-data-swapped-p))
1122 (with-current-buffer tar-data-buffer
1123 (let* ((start (- (tar-header-data-start descriptor) 512)))
1125 ;; delete the old field and insert a new one.
1126 (goto-char (+ start data-position))
1127 (delete-region (point) (+ (point) (length new-data-string))) ; <--
1128 (cl-assert (not (or enable-multibyte-characters
1129 (multibyte-string-p new-data-string))))
1130 (insert new-data-string)
1132 ;; compute a new checksum and insert it.
1133 (let ((chk (tar-header-block-checksum
1134 (buffer-substring start (+ start 512)))))
1135 (goto-char (+ start tar-chk-offset))
1136 (delete-region (point) (+ (point) 8))
1137 (insert (format "%6o\0 " chk))
1138 (setf (tar-header-checksum descriptor) chk)
1140 ;; ok, make sure we didn't botch it.
1141 (tar-header-block-check-checksum
1142 (buffer-substring start (+ start 512))
1143 chk (tar-header-name descriptor))
1147 (defun tar-octal-time (timeval)
1148 ;; Format a timestamp as 11 octal digits. Ghod, I hope this works...
1149 (let ((hibits (car timeval)) (lobits (car (cdr timeval))))
1150 (format "%05o%01o%05o"
1152 (logior (lsh (logand 3 hibits) 1)
1153 (if (> (logand lobits 32768) 0) 1 0))
1154 (logand 32767 lobits)
1157 (defun tar-subfile-save-buffer ()
1158 "In tar subfile mode, save this buffer into its parent tar-file buffer.
1159 This doesn't write anything to disk; you must save the parent tar-file buffer
1160 to make your changes permanent."
1162 (if (not (and (boundp 'tar-superior-buffer) tar-superior-buffer))
1163 (error "This buffer has no superior tar file buffer"))
1164 (if (not (and (boundp 'tar-superior-descriptor) tar-superior-descriptor))
1165 (error "This buffer doesn't have an index into its superior tar file!"))
1166 (let ((subfile (current-buffer))
1167 (coding buffer-file-coding-system)
1168 (descriptor tar-superior-descriptor)
1170 (with-current-buffer tar-superior-buffer
1171 (let* ((start (tar-header-data-start 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 ;;; tar-mode.el ends here
HCoop / bpt / emacs.git / blob