1 ;;; tar-mode.el --- simple editing of tar files from GNU emacs
3 ;; Copyright (C) 1990,91,93,94,95,96,97,98,99,2000,2001
4 ;; Free Software Foundation, Inc.
6 ;; Author: Jamie Zawinski <jwz@lucid.com>
8 ;; Created: 04 Apr 1990
11 ;; This file is part of GNU Emacs.
13 ;; GNU Emacs is free software; you can redistribute it and/or modify
14 ;; it under the terms of the GNU General Public License as published by
15 ;; the Free Software Foundation; either version 2, or (at your option)
18 ;; GNU Emacs is distributed in the hope that it will be useful,
19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 ;; GNU General Public License for more details.
23 ;; You should have received a copy of the GNU General Public License
24 ;; along with GNU Emacs; see the file COPYING. If not, write to the
25 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
26 ;; Boston, MA 02111-1307, USA.
30 ;; This package attempts to make dealing with Unix 'tar' archives easier.
31 ;; When this code is loaded, visiting a file whose name ends in '.tar' will
32 ;; cause the contents of that archive file to be displayed in a Dired-like
33 ;; listing. It is then possible to use the customary Dired keybindings to
34 ;; extract sub-files from that archive, either by reading them into their own
35 ;; editor buffers, or by copying them directly to arbitrary files on disk.
36 ;; It is also possible to delete sub-files from within the tar file and write
37 ;; the modified archive back to disk, or to edit sub-files within the archive
38 ;; and re-insert the modified files into the archive. See the documentation
39 ;; string of tar-mode for more info.
41 ;; This code now understands the extra fields that GNU tar adds to tar files.
43 ;; This interacts correctly with "uncompress.el" in the Emacs library,
46 ;; (autoload 'uncompress-while-visiting "uncompress")
47 ;; (setq auto-mode-alist (cons '("\\.Z$" . uncompress-while-visiting)
50 ;; Do not attempt to use tar-mode.el with crypt.el, you will lose.
52 ;; *************** TO DO ***************
54 ;; o chmod should understand "a+x,og-w".
56 ;; o It's not possible to add a NEW file to a tar archive; not that
57 ;; important, but still...
59 ;; o The code is less efficient that it could be - in a lot of places, I
60 ;; pull a 512-character string out of the buffer and parse it, when I could
61 ;; be parsing it in place, not garbaging a string. Should redo that.
63 ;; o I'd like a command that searches for a string/regexp in every subfile
64 ;; of an archive, where <esc> would leave you in a subfile-edit buffer.
65 ;; (Like the Meta-R command of the Zmacs mail reader.)
67 ;; o Sometimes (but not always) reverting the tar-file buffer does not
68 ;; re-grind the listing, and you are staring at the binary tar data.
69 ;; Typing 'g' again immediately after that will always revert and re-grind
70 ;; it, though. I have no idea why this happens.
72 ;; o Tar-mode interacts poorly with crypt.el and zcat.el because the tar
73 ;; write-file-hook actually writes the file. Instead it should remove the
74 ;; header (and conspire to put it back afterwards) so that other write-file
75 ;; hooks which frob the buffer have a chance to do their dirty work. There
76 ;; might be a problem if the tar write-file-hook does not come *first* on
79 ;; o Block files, sparse files, continuation files, and the various header
80 ;; types aren't editable. Actually I don't know that they work at all.
84 ;; Why does tar-mode edit the file itself instead of using tar?
86 ;; That means that you can edit tar files which you don't have room for
87 ;; on your local disk.
89 ;; I don't know about recent features in gnu tar, but old versions of tar
90 ;; can't replace a file in the middle of a tar file with a new version.
91 ;; Tar-mode can. I don't think tar can do things like chmod the subfiles.
92 ;; An implementation which involved unpacking and repacking the file into
93 ;; some scratch directory would be very wasteful, and wouldn't be able to
94 ;; preserve the file owners.
99 "Simple editing of tar files."
103 (defcustom tar-anal-blocksize
20
104 "*The blocksize of tar files written by Emacs, or nil, meaning don't care.
105 The blocksize of a tar file is not really the size of the blocks; rather, it is
106 the number of blocks written with one system call. When tarring to a tape,
107 this is the size of the *tape* blocks, but when writing to a file, it doesn't
108 matter much. The only noticeable difference is that if a tar file does not
109 have a blocksize of 20, tar will tell you that; all this really controls is
110 how many null padding bytes go on the end of the tar file."
111 :type
'(choice integer
(const nil
))
114 (defcustom tar-update-datestamp nil
115 "*Non-nil means Tar mode should play fast and loose with sub-file datestamps.
116 If this is true, then editing and saving a tar file entry back into its
117 tar file will update its datestamp. If false, the datestamp is unchanged.
118 You may or may not want this - it is good in that you can tell when a file
119 in a tar archive has been changed, but it is bad for the same reason that
120 editing a file in the tar archive at all is bad - the changed version of
121 the file never exists on disk."
125 (defcustom tar-mode-show-date nil
126 "*Non-nil means Tar mode should show the date/time of each subfile.
127 This information is useful, but it takes screen space away from file names."
131 (defvar tar-parse-info nil
)
132 (defvar tar-header-offset nil
)
133 (defvar tar-superior-buffer nil
)
134 (defvar tar-superior-descriptor nil
)
135 (defvar tar-subfile-mode nil
)
136 (defvar tar-file-name-coding-system nil
)
138 (put 'tar-parse-info
'permanent-local t
)
139 (put 'tar-header-offset
'permanent-local t
)
140 (put 'tar-superior-buffer
'permanent-local t
)
141 (put 'tar-superior-descriptor
'permanent-local t
)
142 (put 'tar-file-name-coding-system
'permanent-local t
)
144 (defmacro tar-setf
(form val
)
145 "A mind-numbingly simple implementation of setf."
146 (let ((mform (macroexpand form
(and (boundp 'byte-compile-macro-environment
)
147 byte-compile-macro-environment
))))
148 (cond ((symbolp mform
) (list 'setq mform val
))
149 ((not (consp mform
)) (error "can't setf %s" form
))
150 ((eq (car mform
) 'aref
)
151 (list 'aset
(nth 1 mform
) (nth 2 mform
) val
))
152 ((eq (car mform
) 'car
)
153 (list 'setcar
(nth 1 mform
) val
))
154 ((eq (car mform
) 'cdr
)
155 (list 'setcdr
(nth 1 mform
) val
))
156 (t (error "don't know how to setf %s" form
)))))
158 ;;; down to business.
160 (defmacro make-tar-header
(name mode uid git size date ck lt ln
161 magic uname gname devmaj devmin
)
162 (list 'vector name mode uid git size date ck lt ln
163 magic uname gname devmaj devmin
))
165 (defmacro tar-header-name
(x) (list 'aref x
0))
166 (defmacro tar-header-mode
(x) (list 'aref x
1))
167 (defmacro tar-header-uid
(x) (list 'aref x
2))
168 (defmacro tar-header-gid
(x) (list 'aref x
3))
169 (defmacro tar-header-size
(x) (list 'aref x
4))
170 (defmacro tar-header-date
(x) (list 'aref x
5))
171 (defmacro tar-header-checksum
(x) (list 'aref x
6))
172 (defmacro tar-header-link-type
(x) (list 'aref x
7))
173 (defmacro tar-header-link-name
(x) (list 'aref x
8))
174 (defmacro tar-header-magic
(x) (list 'aref x
9))
175 (defmacro tar-header-uname
(x) (list 'aref x
10))
176 (defmacro tar-header-gname
(x) (list 'aref x
11))
177 (defmacro tar-header-dmaj
(x) (list 'aref x
12))
178 (defmacro tar-header-dmin
(x) (list 'aref x
13))
180 (defmacro make-tar-desc
(data-start tokens
)
181 (list 'cons data-start tokens
))
183 (defmacro tar-desc-data-start
(x) (list 'car x
))
184 (defmacro tar-desc-tokens
(x) (list 'cdr x
))
186 (defconst tar-name-offset
0)
187 (defconst tar-mode-offset
(+ tar-name-offset
100))
188 (defconst tar-uid-offset
(+ tar-mode-offset
8))
189 (defconst tar-gid-offset
(+ tar-uid-offset
8))
190 (defconst tar-size-offset
(+ tar-gid-offset
8))
191 (defconst tar-time-offset
(+ tar-size-offset
12))
192 (defconst tar-chk-offset
(+ tar-time-offset
12))
193 (defconst tar-linkp-offset
(+ tar-chk-offset
8))
194 (defconst tar-link-offset
(+ tar-linkp-offset
1))
195 ;;; GNU-tar specific slots.
196 (defconst tar-magic-offset
(+ tar-link-offset
100))
197 (defconst tar-uname-offset
(+ tar-magic-offset
8))
198 (defconst tar-gname-offset
(+ tar-uname-offset
32))
199 (defconst tar-dmaj-offset
(+ tar-gname-offset
32))
200 (defconst tar-dmin-offset
(+ tar-dmaj-offset
8))
201 (defconst tar-end-offset
(+ tar-dmin-offset
8))
203 (defun tar-header-block-tokenize (string)
204 "Return a `tar-header' structure.
205 This is a list of name, mode, uid, gid, size,
206 write-date, checksum, link-type, and link-name."
207 (cond ((< (length string
) 512) nil
)
208 (;(some 'plusp string) ; <-- oops, massive cycle hog!
209 (or (not (= 0 (aref string
0))) ; This will do.
210 (not (= 0 (aref string
101))))
211 (let* ((name-end (1- tar-mode-offset
))
212 (link-end (1- tar-magic-offset
))
213 (uname-end (1- tar-gname-offset
))
214 (gname-end (1- tar-dmaj-offset
))
215 (link-p (aref string tar-linkp-offset
))
216 (magic-str (substring string tar-magic-offset
(1- tar-uname-offset
)))
217 (uname-valid-p (or (string= "ustar " magic-str
) (string= "GNUtar " magic-str
)))
219 (nulsexp "[^\000]*\000"))
220 (when (string-match nulsexp string tar-name-offset
)
221 (setq name-end
(min name-end
(1- (match-end 0)))))
222 (when (string-match nulsexp string tar-link-offset
)
223 (setq link-end
(min link-end
(1- (match-end 0)))))
224 (when (string-match nulsexp string tar-uname-offset
)
225 (setq uname-end
(min uname-end
(1- (match-end 0)))))
226 (when (string-match nulsexp string tar-gname-offset
)
227 (setq gname-end
(min gname-end
(1- (match-end 0)))))
228 (setq name
(substring string tar-name-offset name-end
)
229 link-p
(if (or (= link-p
0) (= link-p ?
0))
232 (setq linkname
(substring string tar-link-offset link-end
))
233 (if default-enable-multibyte-characters
235 (decode-coding-string name tar-file-name-coding-system
)
237 (decode-coding-string linkname
238 tar-file-name-coding-system
)))
239 (if (and (null link-p
) (string-match "/$" name
)) (setq link-p
5)) ; directory
242 (tar-parse-octal-integer string tar-mode-offset tar-uid-offset
)
243 (tar-parse-octal-integer string tar-uid-offset tar-gid-offset
)
244 (tar-parse-octal-integer string tar-gid-offset tar-size-offset
)
245 (tar-parse-octal-integer string tar-size-offset tar-time-offset
)
246 (tar-parse-octal-long-integer string tar-time-offset tar-chk-offset
)
247 (tar-parse-octal-integer string tar-chk-offset tar-linkp-offset
)
251 (and uname-valid-p
(substring string tar-uname-offset uname-end
))
252 (and uname-valid-p
(substring string tar-gname-offset gname-end
))
253 (tar-parse-octal-integer string tar-dmaj-offset tar-dmin-offset
)
254 (tar-parse-octal-integer string tar-dmin-offset tar-end-offset
)
256 (t 'empty-tar-block
)))
259 (defun tar-parse-octal-integer (string &optional start end
)
260 (if (null start
) (setq start
0))
261 (if (null end
) (setq end
(length string
)))
262 (if (= (aref string start
) 0)
266 (setq n
(if (< (aref string start
) ?
0) n
267 (+ (* n
8) (- (aref string start
) ?
0)))
271 (defun tar-parse-octal-long-integer (string &optional start end
)
272 (if (null start
) (setq start
0))
273 (if (null end
) (setq end
(length string
)))
274 (if (= (aref string start
) 0)
279 (if (>= (aref string start
) ?
0)
280 (setq lo
(+ (* lo
8) (- (aref string start
) ?
0))
281 hi
(+ (* hi
8) (ash lo -
16))
282 lo
(logand lo
65535)))
283 (setq start
(1+ start
)))
286 (defun tar-parse-octal-integer-safe (string)
287 (let ((L (length string
)))
288 (if (= L
0) (error "empty string"))
290 (if (or (< (aref string i
) ?
0)
291 (> (aref string i
) ?
7))
292 (error "`%c' is not an octal digit"))))
293 (tar-parse-octal-integer string
))
296 (defun tar-header-block-checksum (string)
297 "Compute and return a tar-acceptable checksum for this block."
298 (let* ((chk-field-start tar-chk-offset
)
299 (chk-field-end (+ chk-field-start
8))
302 ;; Add up all of the characters except the ones in the checksum field.
303 ;; Add that field as if it were filled with spaces.
304 (while (< i chk-field-start
)
305 (setq sum
(+ sum
(multibyte-char-to-unibyte (aref string i
)))
307 (setq i chk-field-end
)
309 (setq sum
(+ sum
(multibyte-char-to-unibyte (aref string i
)))
313 (defun tar-header-block-check-checksum (hblock desired-checksum file-name
)
314 "Beep and print a warning if the checksum doesn't match."
315 (if (not (= desired-checksum
(tar-header-block-checksum hblock
)))
316 (progn (beep) (message "Invalid checksum for file %s!" file-name
))))
318 (defun tar-clip-time-string (time)
319 (let ((str (current-time-string time
)))
320 (concat " " (substring str
4 16) (substring str
19 24))))
322 (defun tar-grind-file-mode (mode)
323 "Construct a `-rw--r--r--' string indicating MODE.
324 MODE should be an integer which is a file mode value."
326 (if (zerop (logand 256 mode
)) ?- ?r
)
327 (if (zerop (logand 128 mode
)) ?- ?w
)
328 (if (zerop (logand 1024 mode
)) (if (zerop (logand 64 mode
)) ?- ?x
) ?s
)
329 (if (zerop (logand 32 mode
)) ?- ?r
)
330 (if (zerop (logand 16 mode
)) ?- ?w
)
331 (if (zerop (logand 2048 mode
)) (if (zerop (logand 8 mode
)) ?- ?x
) ?s
)
332 (if (zerop (logand 4 mode
)) ?- ?r
)
333 (if (zerop (logand 2 mode
)) ?- ?w
)
334 (if (zerop (logand 1 mode
)) ?- ?x
)))
336 (defun tar-header-block-summarize (tar-hblock &optional mod-p
)
337 "Return a line similar to the output of `tar -vtf'."
338 (let ((name (tar-header-name tar-hblock
))
339 (mode (tar-header-mode tar-hblock
))
340 (uid (tar-header-uid tar-hblock
))
341 (gid (tar-header-gid tar-hblock
))
342 (uname (tar-header-uname tar-hblock
))
343 (gname (tar-header-gname tar-hblock
))
344 (size (tar-header-size tar-hblock
))
345 (time (tar-header-date tar-hblock
))
346 (ck (tar-header-checksum tar-hblock
))
347 (type (tar-header-link-type tar-hblock
))
348 (link-name (tar-header-link-name tar-hblock
)))
349 (format "%c%c%s%8s/%-8s%7s%s %s%s"
351 (cond ((or (eq type nil
) (eq type
0)) ?-
)
352 ((eq type
1) ?l
) ; link
353 ((eq type
2) ?s
) ; symlink
354 ((eq type
3) ?c
) ; char special
355 ((eq type
4) ?b
) ; block special
356 ((eq type
5) ?d
) ; directory
357 ((eq type
6) ?p
) ; FIFO/pipe
358 ((eq type
20) ?
*) ; directory listing
359 ((eq type
29) ?M
) ; multivolume continuation
360 ((eq type
35) ?S
) ; sparse
361 ((eq type
38) ?V
) ; volume header
364 (tar-grind-file-mode mode
)
365 (if (= 0 (length uname
)) uid uname
)
366 (if (= 0 (length gname
)) gid gname
)
368 (if tar-mode-show-date
(tar-clip-time-string time
) "")
370 'mouse-face
'highlight
371 'help-echo
"mouse-2: extract this file into a buffer")
372 (if (or (eq type
1) (eq type
2))
373 (concat (if (= type
1) " ==> " " --> ") link-name
)
376 (defun tar-summarize-buffer ()
377 "Parse the contents of the tar file in the current buffer.
378 Place a dired-like listing on the front;
379 then narrow to it, so that only that listing
380 is visible (and the real data of the buffer is hidden)."
381 (set-buffer-multibyte nil
)
382 (message "Parsing tar file...")
385 (bs (max 1 (- (buffer-size) 1024))) ; always 2+ empty blocks at end.
386 (bs100 (max 1 (/ bs
100)))
388 (while (and (<= (+ pos
512) (point-max))
389 (not (eq 'empty-tar-block
391 (tar-header-block-tokenize
392 (buffer-substring pos
(+ pos
512)))))))
393 (setq pos
(+ pos
512))
394 (message "Parsing tar file...%d%%"
395 ;(/ (* pos 100) bs) ; this gets round-off lossage
396 (/ pos bs100
) ; this doesn't
398 (if (eq (tar-header-link-type tokens
) 20)
399 ;; Foo. There's an extra empty block after these.
400 (setq pos
(+ pos
512)))
401 (let ((size (tar-header-size tokens
)))
403 (error "%s has size %s - corrupted"
404 (tar-header-name tokens
) size
))
406 ; This is just too slow. Don't really need it anyway....
407 ;(tar-header-block-check-checksum
408 ; hblock (tar-header-block-checksum hblock)
409 ; (tar-header-name tokens))
411 (setq result
(cons (make-tar-desc pos tokens
) result
))
413 (and (null (tar-header-link-type tokens
))
416 (+ pos
512 (ash (ash (1- size
) -
9) 9)) ; this works
417 ;(+ pos (+ size (- 512 (rem (1- size) 512)))) ; this doesn't
419 (make-local-variable 'tar-parse-info
)
420 (setq tar-parse-info
(nreverse result
))
421 ;; A tar file should end with a block or two of nulls,
422 ;; but let's not get a fatal error if it doesn't.
423 (if (eq tokens
'empty-tar-block
)
424 (message "Parsing tar file...done")
425 (message "Warning: premature EOF parsing tar file")))
427 (goto-char (point-min))
428 (let ((buffer-read-only nil
)
430 ;; Collect summary lines and insert them all at once since tar files
431 ;; can be pretty big.
432 (dolist (tar-desc (reverse tar-parse-info
))
434 (cons (tar-header-block-summarize (tar-desc-tokens tar-desc
))
437 (if default-enable-multibyte-characters
438 (set-buffer-multibyte t
'to
))
439 (let ((total-summaries (apply 'concat summaries
)))
440 (insert total-summaries
))
441 (make-local-variable 'tar-header-offset
)
442 (setq tar-header-offset
(point))
443 (narrow-to-region 1 tar-header-offset
)
444 (set-buffer-modified-p nil
))))
446 (defvar tar-mode-map nil
"*Local keymap for Tar mode listings.")
450 (setq tar-mode-map
(make-keymap))
451 (suppress-keymap tar-mode-map
)
452 (define-key tar-mode-map
" " 'tar-next-line
)
453 (define-key tar-mode-map
"C" 'tar-copy
)
454 (define-key tar-mode-map
"d" 'tar-flag-deleted
)
455 (define-key tar-mode-map
"\^D" 'tar-flag-deleted
)
456 (define-key tar-mode-map
"e" 'tar-extract
)
457 (define-key tar-mode-map
"f" 'tar-extract
)
458 (define-key tar-mode-map
"\C-m" 'tar-extract
)
459 (define-key tar-mode-map
[mouse-2
] 'tar-mouse-extract
)
460 (define-key tar-mode-map
"g" 'revert-buffer
)
461 (define-key tar-mode-map
"h" 'describe-mode
)
462 (define-key tar-mode-map
"n" 'tar-next-line
)
463 (define-key tar-mode-map
"\^N" 'tar-next-line
)
464 (define-key tar-mode-map
[down] 'tar-next-line)
465 (define-key tar-mode-map "o" 'tar-extract-other-window)
466 (define-key tar-mode-map "p" 'tar-previous-line)
467 (define-key tar-mode-map "q" 'quit-window)
468 (define-key tar-mode-map "\^P" 'tar-previous-line)
469 (define-key tar-mode-map [up] 'tar-previous-line)
470 (define-key tar-mode-map "R" 'tar-rename-entry)
471 (define-key tar-mode-map "u" 'tar-unflag)
472 (define-key tar-mode-map "v" 'tar-view)
473 (define-key tar-mode-map "x" 'tar-expunge)
474 (define-key tar-mode-map "\177" 'tar-unflag-backwards)
475 (define-key tar-mode-map "E" 'tar-extract-other-window)
476 (define-key tar-mode-map "M" 'tar-chmod-entry)
477 (define-key tar-mode-map "G" 'tar-chgrp-entry)
478 (define-key tar-mode-map "O" 'tar-chown-entry)
481 ;; Make menu bar items.
483 ;; Get rid of the Edit menu bar item to save space.
484 (define-key tar-mode-map [menu-bar edit] 'undefined)
486 (define-key tar-mode-map [menu-bar immediate]
487 (cons "Immediate" (make-sparse-keymap "Immediate")))
489 (define-key tar-mode-map [menu-bar immediate view]
490 '("View This File" . tar-view))
491 (define-key tar-mode-map [menu-bar immediate display]
492 '("Display in Other Window" . tar-display-other-window))
493 (define-key tar-mode-map [menu-bar immediate find-file-other-window]
494 '("Find in Other Window" . tar-extract-other-window))
495 (define-key tar-mode-map [menu-bar immediate find-file]
496 '("Find This File" . tar-extract))
498 (define-key tar-mode-map [menu-bar mark]
499 (cons "Mark" (make-sparse-keymap "Mark")))
501 (define-key tar-mode-map [menu-bar mark unmark-all]
502 '("Unmark All" . tar-clear-modification-flags))
503 (define-key tar-mode-map [menu-bar mark deletion]
504 '("Flag" . tar-flag-deleted))
505 (define-key tar-mode-map [menu-bar mark unmark]
506 '("Unflag" . tar-unflag))
508 (define-key tar-mode-map [menu-bar operate]
509 (cons "Operate" (make-sparse-keymap "Operate")))
511 (define-key tar-mode-map [menu-bar operate chown]
512 '("Change Owner..." . tar-chown-entry))
513 (define-key tar-mode-map [menu-bar operate chgrp]
514 '("Change Group..." . tar-chgrp-entry))
515 (define-key tar-mode-map [menu-bar operate chmod]
516 '("Change Mode..." . tar-chmod-entry))
517 (define-key tar-mode-map [menu-bar operate rename]
518 '("Rename to..." . tar-rename-entry))
519 (define-key tar-mode-map [menu-bar operate copy]
520 '("Copy to..." . tar-copy))
521 (define-key tar-mode-map [menu-bar operate expunge]
522 '("Expunge Marked Files" . tar-expunge))
524 ;; tar mode is suitable only for specially formatted data.
525 (put 'tar-mode 'mode-class 'special)
526 (put 'tar-subfile-mode 'mode-class 'special)
529 (define-derived-mode tar-mode nil "Tar"
530 "Major mode for viewing a tar file as a dired-like listing of its contents.
531 You can move around using the usual cursor motion commands.
532 Letters no longer insert themselves.
533 Type `e' to pull a file out of the tar file and into its own buffer;
534 or click mouse-2 on the file's line in the Tar mode buffer.
535 Type `c' to copy an entry from the tar file into another file on disk.
537 If you edit a sub-file of this archive (as with the `e' command) and
538 save it with Control-x Control-s, the contents of that buffer will be
539 saved back into the tar-file buffer; in this way you can edit a file
540 inside of a tar archive without extracting it and re-archiving it.
542 See also: variables `tar-update-datestamp' and `tar-anal-blocksize'.
544 ;; this is not interactive because you shouldn't be turning this
545 ;; mode on and off. You can corrupt things that way.
546 ;; rms: with permanent locals, it should now be possible to make this work
547 ;; interactively in some reasonable fashion.
548 (make-local-variable 'tar-header-offset)
549 (make-local-variable 'tar-parse-info)
550 (set (make-local-variable 'require-final-newline) nil) ; binary data, dude...
551 (set (make-local-variable 'revert-buffer-function) 'tar-mode-revert)
552 (set (make-local-variable 'local-enable-local-variables) nil)
553 (set (make-local-variable 'next-line-add-newlines) nil)
554 (set (make-local-variable 'tar-file-name-coding-system)
555 (or file-name-coding-system
556 default-file-name-coding-system
557 locale-coding-system))
558 ;; Prevent loss of data when saving the file.
559 (set (make-local-variable 'file-precious-flag) t)
561 (set (make-local-variable 'write-contents-hooks) '(tar-mode-write-file))
563 (if (and (boundp 'tar-header-offset) tar-header-offset)
564 (narrow-to-region 1 tar-header-offset)
565 (tar-summarize-buffer)
569 (defun tar-subfile-mode (p)
570 "Minor mode for editing an element of a tar-file.
571 This mode arranges for \"saving\" this buffer to write the data
572 into the tar-file buffer that it came from. The changes will actually
573 appear on disk when you save the tar-file's buffer."
575 (or (and (boundp 'tar-superior-buffer) tar-superior-buffer)
576 (error "This buffer is not an element of a tar file"))
577 ;;; Don't do this, because it is redundant and wastes mode line space.
578 ;;; (or (assq 'tar-subfile-mode minor-mode-alist)
579 ;;; (setq minor-mode-alist (append minor-mode-alist
580 ;;; (list '(tar-subfile-mode " TarFile")))))
581 (make-local-variable 'tar-subfile-mode)
582 (setq tar-subfile-mode
584 (not tar-subfile-mode)
585 (> (prefix-numeric-value p) 0)))
586 (cond (tar-subfile-mode
587 (make-local-variable 'local-write-file-hooks)
588 (setq local-write-file-hooks '(tar-subfile-save-buffer))
589 ;; turn off auto-save.
591 (setq buffer-auto-save-file-name nil)
592 (run-hooks 'tar-subfile-mode-hook))
594 (kill-local-variable 'local-write-file-hooks))))
597 ;; Revert the buffer and recompute the dired-like listing.
598 (defun tar-mode-revert (&optional no-auto-save no-confirm)
599 (let ((revert-buffer-function nil)
600 (old-offset tar-header-offset)
602 (setq tar-header-offset nil)
604 (and (revert-buffer t no-confirm)
608 ;; If the revert was canceled,
609 ;; put back the old value of tar-header-offset.
611 (setq tar-header-offset old-offset)))))
614 (defun tar-next-line (arg)
615 "Move cursor vertically down ARG lines and to the start of the filename."
618 (if (eobp) nil (forward-char (if tar-mode-show-date 54 36))))
620 (defun tar-previous-line (arg)
621 "Move cursor vertically up ARG lines and to the start of the filename."
623 (tar-next-line (- arg)))
625 (defun tar-current-descriptor (&optional noerror)
626 "Return the tar-descriptor of the current line, or signals an error."
627 ;; I wish lines had plists, like in ZMACS...
628 (or (nth (count-lines (point-min)
629 (save-excursion (beginning-of-line) (point)))
633 (error "This line does not describe a tar-file entry"))))
635 (defun tar-get-descriptor ()
636 (let* ((descriptor (tar-current-descriptor))
637 (tokens (tar-desc-tokens descriptor))
638 (size (tar-header-size tokens))
639 (link-p (tar-header-link-type tokens)))
641 (error "This is a %s, not a real file"
642 (cond ((eq link-p 5) "directory")
643 ((eq link-p 20) "tar directory header")
644 ((eq link-p 29) "multivolume-continuation")
645 ((eq link-p 35) "sparse entry")
646 ((eq link-p 38) "volume header")
648 (if (zerop size) (error "This is a zero-length file"))
651 (defun tar-mouse-extract (event)
652 "Extract a file whose tar directory line you click on."
655 (set-buffer (window-buffer (posn-window (event-end event))))
657 (goto-char (posn-point (event-end event)))
658 ;; Just make sure this doesn't get an error.
659 (tar-get-descriptor)))
660 (select-window (posn-window (event-end event)))
661 (goto-char (posn-point (event-end event)))
664 (defun tar-extract (&optional other-window-p)
665 "In Tar mode, extract this entry of the tar file into its own buffer."
667 (let* ((view-p (eq other-window-p 'view))
668 (descriptor (tar-get-descriptor))
669 (tokens (tar-desc-tokens descriptor))
670 (name (tar-header-name tokens))
671 (size (tar-header-size tokens))
672 (start (+ (tar-desc-data-start descriptor) tar-header-offset -1))
673 (end (+ start size)))
674 (let* ((tar-buffer (current-buffer))
675 (tar-buffer-multibyte enable-multibyte-characters)
676 (tarname (buffer-name))
677 (bufname (concat (file-name-nondirectory name)
681 (read-only-p (or buffer-read-only view-p))
682 (new-buffer-file-name (expand-file-name
683 ;; `:' is not allowed on Windows
684 (concat tarname "!" name)))
685 (buffer (get-file-buffer new-buffer-file-name))
689 (setq buffer (generate-new-buffer bufname))
690 (setq bufname (buffer-name buffer))
691 (setq just-created t)
694 (narrow-to-region start end)
696 (setq coding (or coding-system-for-read
697 (and set-auto-coding-function
698 (funcall set-auto-coding-function
701 (eq (coding-system-type coding) 'undecided))
702 (setq coding (detect-coding-region start end t)))
703 (if (eq (coding-system-type coding) 'undecided)
705 (coding-system-change-text-conversion coding
709 (if (and enable-multibyte-characters
710 (eq (coding-system-type 'raw-text) coding))
711 (set-buffer-multibyte nil))
712 (goto-char (point-min))
713 (setq buffer-file-name new-buffer-file-name)
714 (setq buffer-file-truename
715 (abbreviate-file-name buffer-file-name)))
716 (decode-coding-region start end coding buffer)
719 (goto-char (point-min))
720 ;; Set the default-directory to the dir of the
722 (setq default-directory
724 (set-buffer tar-buffer)
726 (normal-mode) ; pick a mode.
727 (rename-buffer bufname)
728 (make-local-variable 'tar-superior-buffer)
729 (make-local-variable 'tar-superior-descriptor)
730 (setq tar-superior-buffer tar-buffer)
731 (setq tar-superior-descriptor descriptor)
732 (setq buffer-read-only read-only-p)
733 (set-buffer-modified-p nil)
734 (tar-subfile-mode 1))
735 (set-buffer tar-buffer))
736 (narrow-to-region 1 tar-header-offset)
739 (view-buffer buffer (and just-created 'kill-buffer))
740 (if (eq other-window-p 'display)
741 (display-buffer buffer)
743 (switch-to-buffer-other-window buffer)
744 (switch-to-buffer buffer)))))))
747 (defun tar-extract-other-window ()
748 "*In Tar mode, find this entry of the tar file in another window."
752 (defun tar-display-other-window ()
753 "*In Tar mode, display this entry of the tar file in another window."
755 (tar-extract 'display))
758 "*In Tar mode, view the tar file entry on this line."
763 (defun tar-read-file-name (&optional prompt)
764 "Read a file name with this line's entry as the default."
765 (or prompt (setq prompt "Copy to: "))
766 (let* ((default-file (expand-file-name
767 (tar-header-name (tar-desc-tokens
768 (tar-current-descriptor)))))
769 (target (expand-file-name
770 (read-file-name prompt
771 (file-name-directory default-file)
773 (if (or (string= "" (file-name-nondirectory target))
774 (file-directory-p target))
775 (setq target (concat (if (string-match "/$" target)
776 (substring target 0 (1- (match-end 0)))
779 (file-name-nondirectory default-file))))
783 (defun tar-copy (&optional to-file)
784 "*In Tar mode, extract this entry of the tar file into a file on disk.
785 If TO-FILE is not supplied, it is prompted for, defaulting to the name of
786 the current tar-entry."
787 (interactive (list (tar-read-file-name)))
788 (let* ((descriptor (tar-get-descriptor))
789 (tokens (tar-desc-tokens descriptor))
790 (name (tar-header-name tokens))
791 (size (tar-header-size tokens))
792 (start (+ (tar-desc-data-start descriptor) tar-header-offset -1))
794 (inhibit-file-name-handlers inhibit-file-name-handlers)
795 (inhibit-file-name-operation inhibit-file-name-operation))
798 ;; Inhibit compressing a subfile again if *both* name and
799 ;; to-file are handled by jka-compr
800 (if (and (eq (find-file-name-handler name 'write-region) 'jka-compr-handler)
801 (eq (find-file-name-handler to-file 'write-region) 'jka-compr-handler))
802 (setq inhibit-file-name-handlers
803 (cons 'jka-compr-handler
804 (and (eq inhibit-file-name-operation 'write-region)
805 inhibit-file-name-handlers))
806 inhibit-file-name-operation 'write-region))
807 (let ((coding-system-for-write 'no-conversion))
808 (write-region start end to-file nil nil nil t)))
809 (message "Copied tar entry %s to %s" name to-file)))
811 (defun tar-flag-deleted (p &optional unflag)
812 "*In Tar mode, mark this sub-file to be deleted from the tar file.
813 With a prefix argument, mark that many files."
816 (dotimes (i (if (< p 0) (- p) p))
817 (if (tar-current-descriptor unflag) ; barf if we're not on an entry-line.
820 (insert (if unflag " " "D"))))
821 (forward-line (if (< p 0) -1 1)))
822 (if (eobp) nil (forward-char 36)))
824 (defun tar-unflag (p)
825 "*In Tar mode, un-mark this sub-file if it is marked to be deleted.
826 With a prefix argument, un-mark that many files forward."
828 (tar-flag-deleted p t))
830 (defun tar-unflag-backwards (p)
831 "*In Tar mode, un-mark this sub-file if it is marked to be deleted.
832 With a prefix argument, un-mark that many files backward."
834 (tar-flag-deleted (- p) t))
837 (defun tar-expunge-internal ()
838 "Expunge the tar-entry specified by the current line."
839 (let* ((descriptor (tar-current-descriptor))
840 (tokens (tar-desc-tokens descriptor))
841 (line (tar-desc-data-start descriptor))
842 (name (tar-header-name tokens))
843 (size (tar-header-size tokens))
844 (link-p (tar-header-link-type tokens))
845 (start (tar-desc-data-start descriptor))
846 (following-descs (cdr (memq descriptor tar-parse-info))))
847 (if link-p (setq size 0)) ; size lies for hard-links.
849 ;; delete the current line...
851 (let ((line-start (point)))
852 (end-of-line) (forward-char)
853 (let ((line-len (- (point) line-start)))
854 (delete-region line-start (point))
856 ;; decrement the header-pointer to be in sync...
857 (setq tar-header-offset (- tar-header-offset line-len))))
859 ;; delete the data pointer...
860 (setq tar-parse-info (delq descriptor tar-parse-info))
862 ;; delete the data from inside the file...
864 (let* ((data-start (+ start tar-header-offset -513))
865 (data-end (+ data-start 512 (ash (ash (+ size 511) -9) 9))))
866 (delete-region data-start data-end)
868 ;; and finally, decrement the start-pointers of all following
869 ;; entries in the archive. This is a pig when deleting a bunch
870 ;; of files at once - we could optimize this to only do the
871 ;; iteration over the files that remain, or only iterate up to
872 ;; the next file to be deleted.
873 (let ((data-length (- data-end data-start)))
874 (dolist (desc following-descs)
875 (tar-setf (tar-desc-data-start desc)
876 (- (tar-desc-data-start desc) data-length))))
878 (narrow-to-region 1 tar-header-offset))
881 (defun tar-expunge (&optional noconfirm)
882 "*In Tar mode, delete all the archived files flagged for deletion.
883 This does not modify the disk image; you must save the tar file itself
884 for this to be permanent."
887 (y-or-n-p "Expunge files marked for deletion? "))
890 (goto-char (point-min))
893 (progn (tar-expunge-internal)
896 ;; after doing the deletions, add any padding that may be necessary.
897 (tar-pad-to-blocksize)
898 (narrow-to-region 1 tar-header-offset))
900 (message "Nothing to expunge.")
901 (message "%s files expunged. Be sure to save this buffer." n)))))
904 (defun tar-clear-modification-flags ()
905 "Remove the stars at the beginning of each line."
908 (goto-char (point-min))
909 (while (< (point) tar-header-offset)
910 (if (not (eq (following-char) ?\ ))
911 (progn (delete-char 1) (insert " ")))
915 (defun tar-chown-entry (new-uid)
916 "*Change the user-id associated with this entry in the tar file.
917 If this tar file was written by GNU tar, then you will be able to edit
918 the user id as a string; otherwise, you must edit it as a number.
919 You can force editing as a number by calling this with a prefix arg.
920 This does not modify the disk image; you must save the tar file itself
921 for this to be permanent."
923 (let ((tokens (tar-desc-tokens (tar-current-descriptor))))
924 (if (or current-prefix-arg
925 (not (tar-header-magic tokens)))
927 (while (not (numberp (setq n (read-minibuffer
929 (format "%s" (tar-header-uid tokens)))))))
931 (read-string "New UID string: " (tar-header-uname tokens))))))
932 (cond ((stringp new-uid)
933 (tar-setf (tar-header-uname (tar-desc-tokens (tar-current-descriptor)))
935 (tar-alter-one-field tar-uname-offset (concat new-uid "\000")))
937 (tar-setf (tar-header-uid (tar-desc-tokens (tar-current-descriptor)))
939 (tar-alter-one-field tar-uid-offset
940 (concat (substring (format "%6o" new-uid) 0 6) "\000 ")))))
943 (defun tar-chgrp-entry (new-gid)
944 "*Change the group-id associated with this entry in the tar file.
945 If this tar file was written by GNU tar, then you will be able to edit
946 the group id as a string; otherwise, you must edit it as a number.
947 You can force editing as a number by calling this with a prefix arg.
948 This does not modify the disk image; you must save the tar file itself
949 for this to be permanent."
951 (let ((tokens (tar-desc-tokens (tar-current-descriptor))))
952 (if (or current-prefix-arg
953 (not (tar-header-magic tokens)))
955 (while (not (numberp (setq n (read-minibuffer
957 (format "%s" (tar-header-gid tokens)))))))
959 (read-string "New GID string: " (tar-header-gname tokens))))))
960 (cond ((stringp new-gid)
961 (tar-setf (tar-header-gname (tar-desc-tokens (tar-current-descriptor)))
963 (tar-alter-one-field tar-gname-offset
964 (concat new-gid "\000")))
966 (tar-setf (tar-header-gid (tar-desc-tokens (tar-current-descriptor)))
968 (tar-alter-one-field tar-gid-offset
969 (concat (substring (format "%6o" new-gid) 0 6) "\000 ")))))
971 (defun tar-rename-entry (new-name)
972 "*Change the name associated with this entry in the tar file.
973 This does not modify the disk image; you must save the tar file itself
974 for this to be permanent."
976 (list (read-string "New name: "
977 (tar-header-name (tar-desc-tokens (tar-current-descriptor))))))
978 (if (string= "" new-name) (error "zero length name"))
979 (let ((encoded-new-name (encode-coding-string new-name
980 tar-file-name-coding-system)))
981 (if (> (length encoded-new-name) 98) (error "name too long"))
982 (tar-setf (tar-header-name (tar-desc-tokens (tar-current-descriptor)))
984 (tar-alter-one-field 0
985 (substring (concat encoded-new-name (make-string 99 0)) 0 99))))
988 (defun tar-chmod-entry (new-mode)
989 "*Change the protection bits associated with this entry in the tar file.
990 This does not modify the disk image; you must save the tar file itself
991 for this to be permanent."
992 (interactive (list (tar-parse-octal-integer-safe
993 (read-string "New protection (octal): "))))
994 (tar-setf (tar-header-mode (tar-desc-tokens (tar-current-descriptor)))
996 (tar-alter-one-field tar-mode-offset
997 (concat (substring (format "%6o" new-mode) 0 6) "\000 ")))
1000 (defun tar-alter-one-field (data-position new-data-string)
1001 (let* ((descriptor (tar-current-descriptor))
1002 (tokens (tar-desc-tokens descriptor)))
1006 ;; update the header-line.
1010 (delete-region p (point))
1011 (insert (tar-header-block-summarize tokens) "\n")
1012 (setq tar-header-offset (point-max)))
1015 (let* ((start (+ (tar-desc-data-start descriptor) tar-header-offset -513)))
1017 ;; delete the old field and insert a new one.
1018 (goto-char (+ start data-position))
1019 (delete-region (point) (+ (point) (length new-data-string))) ; <--
1021 ;; As new-data-string is unibyte, just inserting it will
1022 ;; make eight-bit chars to the corresponding multibyte
1023 ;; chars. This avoid that conversion, i.e., eight-bit
1024 ;; chars are converted to multibyte form of eight-bit
1026 (insert (string-to-multibyte new-data-string))
1028 ;; compute a new checksum and insert it.
1029 (let ((chk (tar-header-block-checksum
1030 (buffer-substring start (+ start 512)))))
1031 (goto-char (+ start tar-chk-offset))
1032 (delete-region (point) (+ (point) 8))
1033 (insert (format "%6o" chk))
1036 (tar-setf (tar-header-checksum tokens) chk)
1038 ;; ok, make sure we didn't botch it.
1039 (tar-header-block-check-checksum
1040 (buffer-substring start (+ start 512))
1041 chk (tar-header-name tokens))
1043 (narrow-to-region 1 tar-header-offset)
1044 (tar-next-line 0))))
1047 (defun tar-octal-time (timeval)
1048 ;; Format a timestamp as 11 octal digits. Ghod, I hope this works...
1049 (let ((hibits (car timeval)) (lobits (car (cdr timeval))))
1050 (insert (format "%05o%01o%05o"
1052 (logior (lsh (logand 3 hibits) 1) (> (logand lobits 32768) 0))
1053 (logand 32767 lobits)
1056 (defun tar-subfile-save-buffer ()
1057 "In tar subfile mode, save this buffer into its parent tar-file buffer.
1058 This doesn't write anything to disk; you must save the parent tar-file buffer
1059 to make your changes permanent."
1061 (if (not (and (boundp 'tar-superior-buffer) tar-superior-buffer))
1062 (error "This buffer has no superior tar file buffer"))
1063 (if (not (and (boundp 'tar-superior-descriptor) tar-superior-descriptor))
1064 (error "This buffer doesn't have an index into its superior tar file!"))
1066 (let ((subfile (current-buffer))
1067 (coding buffer-file-coding-system)
1068 (descriptor tar-superior-descriptor)
1070 (set-buffer tar-superior-buffer)
1071 (let* ((tokens (tar-desc-tokens descriptor))
1072 (start (tar-desc-data-start descriptor))
1073 (name (tar-header-name tokens))
1074 (size (tar-header-size tokens))
1075 (size-pad (ash (ash (+ size 511) -9) 9))
1076 (head (memq descriptor tar-parse-info))
1077 (following-descs (cdr head)))
1079 (error "Can't find this tar file entry in its parent tar file!"))
1082 ;; delete the old data...
1083 (let* ((data-start (+ start tar-header-offset -1))
1084 (data-end (+ data-start (ash (ash (+ size 511) -9) 9))))
1085 (narrow-to-region data-start data-end)
1086 (delete-region (point-min) (point-max))
1087 ;; insert the new data...
1088 (goto-char data-start)
1090 (set-buffer subfile)
1093 (encode-coding-region 1 (point-max) coding tar-superior-buffer)))
1094 (setq subfile-size (- (point-max) (point-min)))
1096 ;; pad the new data out to a multiple of 512...
1097 (let ((subfile-size-pad (ash (ash (+ subfile-size 511) -9) 9)))
1098 (goto-char (point-max))
1099 (insert (make-string (- subfile-size-pad subfile-size) 0))
1101 ;; update the data pointer of this and all following files...
1102 (tar-setf (tar-header-size tokens) subfile-size)
1103 (let ((difference (- subfile-size-pad size-pad)))
1104 (dolist (desc following-descs)
1105 (tar-setf (tar-desc-data-start desc)
1106 (+ (tar-desc-data-start desc) difference))))
1108 ;; Update the size field in the header block.
1110 (let ((header-start (- data-start 512)))
1111 (goto-char (+ header-start tar-size-offset))
1112 (delete-region (point) (+ (point) 12))
1113 (insert (format "%11o" subfile-size))
1116 ;; Maybe update the datestamp.
1117 (if (not tar-update-datestamp)
1119 (goto-char (+ header-start tar-time-offset))
1120 (delete-region (point) (+ (point) 12))
1121 (insert (tar-octal-time (current-time)))
1124 ;; compute a new checksum and insert it.
1125 (let ((chk (tar-header-block-checksum
1126 (buffer-substring header-start data-start))))
1127 (goto-char (+ header-start tar-chk-offset))
1128 (delete-region (point) (+ (point) 8))
1129 (insert (format "%6o" chk))
1132 (tar-setf (tar-header-checksum tokens) chk)))
1134 ;; alter the descriptor-line...
1136 (let ((position (- (length tar-parse-info) (length head))))
1137 (goto-char (point-min))
1138 (next-line position)
1142 (m (set-marker (make-marker) tar-header-offset)))
1144 (setq after (point))
1145 ;; Insert the new text after the old, before deleting,
1146 ;; to preserve the window start.
1147 (let ((line (tar-header-block-summarize tokens t)))
1148 (insert-before-markers line "\n"))
1149 (delete-region p after)
1150 (setq tar-header-offset (marker-position m)))
1152 ;; after doing the insertion, add any final padding that may be necessary.
1153 (tar-pad-to-blocksize))
1154 (narrow-to-region 1 tar-header-offset)))
1155 (set-buffer-modified-p t) ; mark the tar file as modified
1157 (set-buffer subfile)
1158 (set-buffer-modified-p nil) ; mark the tar subfile as unmodified
1159 (message "Saved into tar-buffer `%s'. Be sure to save that buffer!"
1160 (buffer-name tar-superior-buffer))
1161 ;; Prevent basic-save-buffer from changing our coding-system.
1162 (setq last-coding-system-used buffer-file-coding-system)
1163 ;; Prevent ordinary saving from happening.
1167 ;; When this function is called, it is sure that the buffer is unibyte.
1168 (defun tar-pad-to-blocksize ()
1169 "If we are being anal about tar file blocksizes, fix up the current buffer.
1170 Leaves the region wide."
1171 (if (null tar-anal-blocksize)
1174 (let* ((last-desc (nth (1- (length tar-parse-info)) tar-parse-info))
1175 (start (tar-desc-data-start last-desc))
1176 (tokens (tar-desc-tokens last-desc))
1177 (link-p (tar-header-link-type tokens))
1178 (size (if link-p 0 (tar-header-size tokens)))
1179 (data-end (+ start size))
1180 (bbytes (ash tar-anal-blocksize 9))
1181 (pad-to (+ bbytes (* bbytes (/ (1- data-end) bbytes))))
1182 (inhibit-read-only t) ; ##
1184 ;; If the padding after the last data is too long, delete some;
1185 ;; else insert some until we are padded out to the right number of blocks.
1187 (goto-char (+ (or tar-header-offset 0) data-end))
1188 (if (> (1+ (buffer-size)) (+ (or tar-header-offset 0) pad-to))
1189 (delete-region (+ (or tar-header-offset 0) pad-to) (1+ (buffer-size)))
1190 (insert (make-string (- (+ (or tar-header-offset 0) pad-to)
1196 ;; Used in write-file-hook to write tar-files out correctly.
1197 (defun tar-mode-write-file ()
1201 ;; Doing this here confuses things - the region gets left too wide!
1202 ;; I suppose this is run in a context where changing the buffer is bad.
1203 ;; (tar-pad-to-blocksize)
1204 ;; tar-header-offset turns out to be null for files fetched with W3,
1206 (let ((coding-system-for-write 'no-conversion))
1207 (write-region (or tar-header-offset
1210 buffer-file-name nil t))
1211 (tar-clear-modification-flags)
1212 (set-buffer-modified-p nil))
1213 (narrow-to-region 1 tar-header-offset))
1214 ;; Return t because we've written the file.
1219 ;;; tar-mode.el ends here