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c88ab9ce | 1 | ;;; tar-mode.el --- simple editing of tar files from GNU emacs |
aa73f29c | 2 | |
eea8d4ef ER |
3 | ;;; Copyright (C) 1990, 1991 Free Software Foundation, Inc. |
4 | ||
22a89ee8 | 5 | ;; Author: Jamie Zawinski <jwz@lucid.com> |
e5167999 | 6 | ;; Created: 04 Apr 1990 |
22a89ee8 | 7 | ;; Version: 1.21 |
d7b4d18f | 8 | ;; Keywords: unix |
aa73f29c | 9 | |
aa73f29c RS |
10 | ;;; This file is part of GNU Emacs. |
11 | ;;; | |
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 | |
e5167999 | 14 | ;;; the Free Software Foundation; either version 2, or (at your option) |
aa73f29c RS |
15 | ;;; any later version. |
16 | ;;; | |
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. | |
21 | ;;; | |
22 | ;;; You should have received a copy of the GNU General Public License | |
23 | ;;; along with GNU Emacs; see the file COPYING. If not, write to | |
24 | ;;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. | |
25 | ||
22a89ee8 ER |
26 | ;;; Commentary: |
27 | ||
aa73f29c RS |
28 | ;;; This package attempts to make dealing with Unix 'tar' archives easier. |
29 | ;;; When this code is loaded, visiting a file whose name ends in '.tar' will | |
30 | ;;; cause the contents of that archive file to be displayed in a Dired-like | |
31 | ;;; listing. It is then possible to use the customary Dired keybindings to | |
32 | ;;; extract sub-files from that archive, either by reading them into their own | |
33 | ;;; editor buffers, or by copying them directly to arbitrary files on disk. | |
34 | ;;; It is also possible to delete sub-files from within the tar file and write | |
35 | ;;; the modified archive back to disk, or to edit sub-files within the archive | |
36 | ;;; and re-insert the modified files into the archive. See the documentation | |
37 | ;;; string of tar-mode for more info. | |
38 | ||
39 | ;;; To autoload, add this to your .emacs file: | |
40 | ;;; | |
41 | ;;; (setq auto-mode-alist (cons '("\\.tar$" . tar-mode) auto-mode-alist)) | |
42 | ;;; (autoload 'tar-mode "tar-mode") | |
43 | ;;; | |
44 | ;;; But beware: for certain tar files - those whose very first file has | |
45 | ;;; a -*- property line - autoloading won't work. See the function | |
46 | ;;; "tar-normal-mode" to understand why. | |
47 | ||
48 | ;;; This code now understands the extra fields that GNU tar adds to tar files. | |
49 | ||
50 | ;;; This interacts correctly with "uncompress.el" in the Emacs library, | |
51 | ;;; which you get with | |
52 | ;;; | |
53 | ;;; (autoload 'uncompress-while-visiting "uncompress") | |
54 | ;;; (setq auto-mode-alist (cons '("\\.Z$" . uncompress-while-visiting) | |
55 | ;;; auto-mode-alist)) | |
56 | ;;; | |
57 | ;;; Do not attempt to use tar-mode.el with crypt.el, you will lose. | |
58 | ||
59 | ;;; *************** TO DO *************** | |
60 | ;;; | |
61 | ;;; o chmod should understand "a+x,og-w". | |
62 | ;;; | |
63 | ;;; o It's not possible to add a NEW file to a tar archive; not that | |
64 | ;;; important, but still... | |
65 | ;;; | |
66 | ;;; o In the directory listing, we don't show creation times because I don't | |
67 | ;;; know how to print an arbitrary date, and I don't really want to have to | |
68 | ;;; implement decode-universal-time. | |
69 | ;;; | |
aa73f29c RS |
70 | ;;; o The code is less efficient that it could be - in a lot of places, I |
71 | ;;; pull a 512-character string out of the buffer and parse it, when I could | |
72 | ;;; be parsing it in place, not garbaging a string. Should redo that. | |
73 | ;;; | |
74 | ;;; o I'd like a command that searches for a string/regexp in every subfile | |
75 | ;;; of an archive, where <esc> would leave you in a subfile-edit buffer. | |
76 | ;;; (Like the Meta-R command of the Zmacs mail reader.) | |
77 | ;;; | |
78 | ;;; o Sometimes (but not always) reverting the tar-file buffer does not | |
79 | ;;; re-grind the listing, and you are staring at the binary tar data. | |
80 | ;;; Typing 'g' again immediately after that will always revert and re-grind | |
81 | ;;; it, though. I have no idea why this happens. | |
82 | ;;; | |
83 | ;;; o Tar-mode interacts poorly with crypt.el and zcat.el because the tar | |
84 | ;;; write-file-hook actually writes the file. Instead it should remove the | |
85 | ;;; header (and conspire to put it back afterwards) so that other write-file | |
86 | ;;; hooks which frob the buffer have a chance to do their dirty work. There | |
87 | ;;; might be a problem if the tar write-file-hook does not come *first* on | |
88 | ;;; the list. | |
89 | ;;; | |
90 | ;;; o Block files, sparse files, continuation files, and the various header | |
91 | ;;; types aren't editable. Actually I don't know that they work at all. | |
92 | ||
22a89ee8 ER |
93 | ;;; Code: |
94 | ||
aa73f29c RS |
95 | (defvar tar-anal-blocksize 20 |
96 | "*The blocksize of tar files written by Emacs, or nil, meaning don't care. | |
97 | The blocksize of a tar file is not really the size of the blocks; rather, it is | |
98 | the number of blocks written with one system call. When tarring to a tape, | |
99 | this is the size of the *tape* blocks, but when writing to a file, it doesn't | |
100 | matter much. The only noticeable difference is that if a tar file does not | |
101 | have a blocksize of 20, tar will tell you that; all this really controls is | |
102 | how many null padding bytes go on the end of the tar file.") | |
103 | ||
104 | (defvar tar-update-datestamp nil | |
105 | "*Whether tar-mode should play fast and loose with sub-file datestamps; | |
106 | if this is true, then editing and saving a tar file entry back into its | |
107 | tar file will update its datestamp. If false, the datestamp is unchanged. | |
108 | You may or may not want this - it is good in that you can tell when a file | |
109 | in a tar archive has been changed, but it is bad for the same reason that | |
110 | editing a file in the tar archive at all is bad - the changed version of | |
49116ac0 | 111 | the file never exists on disk.") |
aa73f29c RS |
112 | |
113 | ||
114 | \f | |
115 | ;;; First, duplicate some Common Lisp functions; I used to just (require 'cl) | |
116 | ;;; but "cl.el" was messing some people up (also it's really big). | |
117 | ||
118 | (defmacro tar-setf (form val) | |
119 | "A mind-numbingly simple implementation of setf." | |
120 | (let ((mform (macroexpand form (and (boundp 'byte-compile-macro-environment) | |
121 | byte-compile-macro-environment)))) | |
122 | (cond ((symbolp mform) (list 'setq mform val)) | |
123 | ((not (consp mform)) (error "can't setf %s" form)) | |
124 | ((eq (car mform) 'aref) | |
125 | (list 'aset (nth 1 mform) (nth 2 mform) val)) | |
126 | ((eq (car mform) 'car) | |
127 | (list 'setcar (nth 1 mform) val)) | |
128 | ((eq (car mform) 'cdr) | |
129 | (list 'setcdr (nth 1 mform) val)) | |
130 | (t (error "don't know how to setf %s" form))))) | |
131 | ||
132 | (defmacro tar-dolist (control &rest body) | |
133 | "syntax: (dolist (var-name list-expr &optional return-value) &body body)" | |
134 | (let ((var (car control)) | |
135 | (init (car (cdr control))) | |
136 | (val (car (cdr (cdr control))))) | |
137 | (list 'let (list (list '_dolist_iterator_ init)) | |
138 | (list 'while '_dolist_iterator_ | |
139 | (cons 'let | |
140 | (cons (list (list var '(car _dolist_iterator_))) | |
141 | (append body | |
142 | (list (list 'setq '_dolist_iterator_ | |
143 | (list 'cdr '_dolist_iterator_))))))) | |
144 | val))) | |
145 | ||
146 | (defmacro tar-dotimes (control &rest body) | |
147 | "syntax: (dolist (var-name count-expr &optional return-value) &body body)" | |
148 | (let ((var (car control)) | |
149 | (n (car (cdr control))) | |
150 | (val (car (cdr (cdr control))))) | |
151 | (list 'let (list (list '_dotimes_end_ n) | |
152 | (list var 0)) | |
153 | (cons 'while | |
154 | (cons (list '< var '_dotimes_end_) | |
155 | (append body | |
156 | (list (list 'setq var (list '1+ var)))))) | |
157 | val))) | |
158 | ||
159 | \f | |
160 | ;;; down to business. | |
161 | ||
162 | (defmacro make-tar-header (name mode uid git size date ck lt ln | |
163 | magic uname gname devmaj devmin) | |
164 | (list 'vector name mode uid git size date ck lt ln | |
165 | magic uname gname devmaj devmin)) | |
166 | ||
167 | (defmacro tar-header-name (x) (list 'aref x 0)) | |
168 | (defmacro tar-header-mode (x) (list 'aref x 1)) | |
169 | (defmacro tar-header-uid (x) (list 'aref x 2)) | |
170 | (defmacro tar-header-gid (x) (list 'aref x 3)) | |
171 | (defmacro tar-header-size (x) (list 'aref x 4)) | |
172 | (defmacro tar-header-date (x) (list 'aref x 5)) | |
173 | (defmacro tar-header-checksum (x) (list 'aref x 6)) | |
174 | (defmacro tar-header-link-type (x) (list 'aref x 7)) | |
175 | (defmacro tar-header-link-name (x) (list 'aref x 8)) | |
176 | (defmacro tar-header-magic (x) (list 'aref x 9)) | |
177 | (defmacro tar-header-uname (x) (list 'aref x 10)) | |
178 | (defmacro tar-header-gname (x) (list 'aref x 11)) | |
179 | (defmacro tar-header-dmaj (x) (list 'aref x 12)) | |
180 | (defmacro tar-header-dmin (x) (list 'aref x 13)) | |
181 | ||
182 | (defmacro make-tar-desc (data-start tokens) | |
183 | (list 'cons data-start tokens)) | |
184 | ||
185 | (defmacro tar-desc-data-start (x) (list 'car x)) | |
186 | (defmacro tar-desc-tokens (x) (list 'cdr x)) | |
187 | ||
188 | (defconst tar-name-offset 0) | |
189 | (defconst tar-mode-offset (+ tar-name-offset 100)) | |
190 | (defconst tar-uid-offset (+ tar-mode-offset 8)) | |
191 | (defconst tar-gid-offset (+ tar-uid-offset 8)) | |
192 | (defconst tar-size-offset (+ tar-gid-offset 8)) | |
193 | (defconst tar-time-offset (+ tar-size-offset 12)) | |
194 | (defconst tar-chk-offset (+ tar-time-offset 12)) | |
195 | (defconst tar-linkp-offset (+ tar-chk-offset 8)) | |
196 | (defconst tar-link-offset (+ tar-linkp-offset 1)) | |
197 | ;;; GNU-tar specific slots. | |
198 | (defconst tar-magic-offset (+ tar-link-offset 100)) | |
199 | (defconst tar-uname-offset (+ tar-magic-offset 8)) | |
200 | (defconst tar-gname-offset (+ tar-uname-offset 32)) | |
201 | (defconst tar-dmaj-offset (+ tar-gname-offset 32)) | |
202 | (defconst tar-dmin-offset (+ tar-dmaj-offset 8)) | |
203 | (defconst tar-end-offset (+ tar-dmin-offset 8)) | |
204 | ||
205 | (defun tokenize-tar-header-block (string) | |
206 | "Returns a 'tar-header' structure (a list of name, mode, uid, gid, size, | |
207 | write-date, checksum, link-type, and link-name)." | |
208 | (cond ((< (length string) 512) nil) | |
209 | (;(some 'plusp string) ; <-- oops, massive cycle hog! | |
210 | (or (not (= 0 (aref string 0))) ; This will do. | |
211 | (not (= 0 (aref string 101)))) | |
212 | (let* ((name-end (1- tar-mode-offset)) | |
213 | (link-end (1- tar-magic-offset)) | |
214 | (uname-end (1- tar-gname-offset)) | |
215 | (gname-end (1- tar-dmaj-offset)) | |
216 | (link-p (aref string tar-linkp-offset)) | |
217 | (magic-str (substring string tar-magic-offset (1- tar-uname-offset))) | |
218 | (uname-valid-p (or (string= "ustar " magic-str) (string= "GNUtar " magic-str))) | |
219 | name | |
220 | (nulsexp "[^\000]*\000")) | |
221 | (and (string-match nulsexp string tar-name-offset) (setq name-end (min name-end (1- (match-end 0))))) | |
222 | (and (string-match nulsexp string tar-link-offset) (setq link-end (min link-end (1- (match-end 0))))) | |
223 | (and (string-match nulsexp string tar-uname-offset) (setq uname-end (min uname-end (1- (match-end 0))))) | |
224 | (and (string-match nulsexp string tar-gname-offset) (setq gname-end (min gname-end (1- (match-end 0))))) | |
225 | (setq name (substring string tar-name-offset name-end) | |
226 | link-p (if (or (= link-p 0) (= link-p ?0)) | |
227 | nil | |
228 | (- link-p ?0))) | |
229 | (if (and (null link-p) (string-match "/$" name)) (setq link-p 5)) ; directory | |
230 | (make-tar-header | |
231 | name | |
232 | (tar-parse-octal-integer string tar-mode-offset (1- tar-uid-offset)) | |
233 | (tar-parse-octal-integer string tar-uid-offset (1- tar-gid-offset)) | |
234 | (tar-parse-octal-integer string tar-gid-offset (1- tar-size-offset)) | |
235 | (tar-parse-octal-integer string tar-size-offset (1- tar-time-offset)) | |
236 | (tar-parse-octal-integer string tar-time-offset (1- tar-chk-offset)) | |
237 | (tar-parse-octal-integer string tar-chk-offset (1- tar-linkp-offset)) | |
238 | link-p | |
239 | (substring string tar-link-offset link-end) | |
240 | uname-valid-p | |
241 | (and uname-valid-p (substring string tar-uname-offset uname-end)) | |
242 | (and uname-valid-p (substring string tar-gname-offset gname-end)) | |
243 | (tar-parse-octal-integer string tar-dmaj-offset (1- tar-dmin-offset)) | |
244 | (tar-parse-octal-integer string tar-dmin-offset (1- tar-end-offset)) | |
245 | ))) | |
246 | (t 'empty-tar-block))) | |
247 | ||
248 | ||
249 | (defun tar-parse-octal-integer (string &optional start end) | |
250 | "deletes all your files, and then reboots." | |
251 | (if (null start) (setq start 0)) | |
252 | (if (null end) (setq end (length string))) | |
253 | (if (= (aref string start) 0) | |
254 | 0 | |
255 | (let ((n 0)) | |
256 | (while (< start end) | |
257 | (setq n (if (< (aref string start) ?0) n | |
258 | (+ (* n 8) (- (aref string start) 48))) | |
259 | start (1+ start))) | |
260 | n))) | |
261 | ||
262 | (defun tar-parse-octal-integer-safe (string) | |
263 | (let ((L (length string))) | |
264 | (if (= L 0) (error "empty string")) | |
265 | (tar-dotimes (i L) | |
266 | (if (or (< (aref string i) ?0) | |
267 | (> (aref string i) ?7)) | |
268 | (error "'%c' is not an octal digit.")))) | |
269 | (tar-parse-octal-integer string)) | |
270 | ||
271 | ||
272 | (defun checksum-tar-header-block (string) | |
273 | "Computes and returns a tar-acceptable checksum for this block." | |
274 | (let* ((chk-field-start tar-chk-offset) | |
275 | (chk-field-end (+ chk-field-start 8)) | |
276 | (sum 0) | |
277 | (i 0)) | |
278 | ;; Add up all of the characters except the ones in the checksum field. | |
279 | ;; Add that field as if it were filled with spaces. | |
280 | (while (< i chk-field-start) | |
281 | (setq sum (+ sum (aref string i)) | |
282 | i (1+ i))) | |
283 | (setq i chk-field-end) | |
284 | (while (< i 512) | |
285 | (setq sum (+ sum (aref string i)) | |
286 | i (1+ i))) | |
287 | (+ sum (* 32 8)))) | |
288 | ||
289 | (defun check-tar-header-block-checksum (hblock desired-checksum file-name) | |
290 | "Beep and print a warning if the checksum doesn't match." | |
291 | (if (not (= desired-checksum (checksum-tar-header-block hblock))) | |
292 | (progn (beep) (message "Invalid checksum for file %s!" file-name)))) | |
293 | ||
294 | (defun recompute-tar-header-block-checksum (hblock) | |
295 | "Modifies the given string to have a valid checksum field." | |
296 | (let* ((chk (checksum-tar-header-block hblock)) | |
297 | (chk-string (format "%6o" chk)) | |
298 | (l (length chk-string))) | |
299 | (aset hblock 154 0) | |
300 | (aset hblock 155 32) | |
301 | (tar-dotimes (i l) (aset hblock (- 153 i) (aref chk-string (- l i 1))))) | |
302 | hblock) | |
303 | ||
304 | ||
305 | (defun tar-grind-file-mode (mode string start) | |
306 | "Write a \"-rw--r--r-\" representing MODE into STRING beginning at START." | |
307 | (aset string start (if (zerop (logand 256 mode)) ?- ?r)) | |
308 | (aset string (+ start 1) (if (zerop (logand 128 mode)) ?- ?w)) | |
309 | (aset string (+ start 2) (if (zerop (logand 64 mode)) ?- ?x)) | |
310 | (aset string (+ start 3) (if (zerop (logand 32 mode)) ?- ?r)) | |
311 | (aset string (+ start 4) (if (zerop (logand 16 mode)) ?- ?w)) | |
312 | (aset string (+ start 5) (if (zerop (logand 8 mode)) ?- ?x)) | |
313 | (aset string (+ start 6) (if (zerop (logand 4 mode)) ?- ?r)) | |
314 | (aset string (+ start 7) (if (zerop (logand 2 mode)) ?- ?w)) | |
315 | (aset string (+ start 8) (if (zerop (logand 1 mode)) ?- ?x)) | |
316 | (if (zerop (logand 1024 mode)) nil (aset string (+ start 2) ?s)) | |
317 | (if (zerop (logand 2048 mode)) nil (aset string (+ start 5) ?s)) | |
318 | string) | |
319 | ||
320 | (defun summarize-tar-header-block (tar-hblock &optional mod-p) | |
321 | "Returns a line similar to the output of 'tar -vtf'." | |
322 | (let ((name (tar-header-name tar-hblock)) | |
323 | (mode (tar-header-mode tar-hblock)) | |
324 | (uid (tar-header-uid tar-hblock)) | |
325 | (gid (tar-header-gid tar-hblock)) | |
326 | (uname (tar-header-uname tar-hblock)) | |
327 | (gname (tar-header-gname tar-hblock)) | |
328 | (size (tar-header-size tar-hblock)) | |
329 | (time (tar-header-date tar-hblock)) | |
330 | (ck (tar-header-checksum tar-hblock)) | |
331 | (link-p (tar-header-link-type tar-hblock)) | |
332 | (link-name (tar-header-link-name tar-hblock)) | |
333 | ) | |
334 | (let* ((left 11) | |
335 | (namew 8) | |
336 | (groupw 8) | |
337 | (sizew 8) | |
338 | (datew 2) | |
339 | (slash (1- (+ left namew))) | |
340 | (lastdigit (+ slash groupw sizew)) | |
341 | (namestart (+ lastdigit datew)) | |
342 | (string (make-string (+ namestart (length name) (if link-p (+ 5 (length link-name)) 0)) 32)) | |
343 | (type (tar-header-link-type tar-hblock))) | |
344 | (aset string 0 (if mod-p ?* ? )) | |
345 | (aset string 1 | |
346 | (cond ((or (eq type nil) (eq type 0)) ?-) | |
347 | ((eq type 1) ?l) ; link | |
348 | ((eq type 2) ?s) ; symlink | |
349 | ((eq type 3) ?c) ; char special | |
350 | ((eq type 4) ?b) ; block special | |
351 | ((eq type 5) ?d) ; directory | |
352 | ((eq type 6) ?p) ; FIFO/pipe | |
353 | ((eq type 20) ?*) ; directory listing | |
354 | ((eq type 29) ?M) ; multivolume continuation | |
355 | ((eq type 35) ?S) ; sparse | |
356 | ((eq type 38) ?V) ; volume header | |
357 | )) | |
358 | (tar-grind-file-mode mode string 2) | |
359 | (setq uid (if (= 0 (length uname)) (int-to-string uid) uname)) | |
360 | (setq gid (if (= 0 (length gname)) (int-to-string gid) gname)) | |
361 | (setq size (int-to-string size)) | |
362 | (tar-dotimes (i (min (1- namew) (length uid))) (aset string (- slash i) (aref uid (- (length uid) i 1)))) | |
363 | (aset string (1+ slash) ?/) | |
364 | (tar-dotimes (i (min (1- groupw) (length gid))) (aset string (+ (+ slash 2) i) (aref gid i))) | |
365 | (tar-dotimes (i (min sizew (length size))) (aset string (- lastdigit i) (aref size (- (length size) i 1)))) | |
366 | ;; ## bloody hell, how do I print an arbitrary date?? | |
367 | (tar-dotimes (i (length name)) (aset string (+ namestart i) (aref name i))) | |
368 | (if (or (eq link-p 1) (eq link-p 2)) | |
369 | (progn | |
370 | (tar-dotimes (i 3) (aset string (+ namestart 1 (length name) i) (aref (if (= link-p 1) "==>" "-->") i))) | |
371 | (tar-dotimes (i (length link-name)) (aset string (+ namestart 5 (length name) i) (aref link-name i))))) | |
372 | string))) | |
373 | ||
374 | ||
375 | (defun tar-summarize-buffer () | |
376 | "Parse the contents of the tar file in the current buffer, and place a | |
377 | dired-like listing on the front; then narrow to it, so that only that listing | |
378 | is visible (and the real data of the buffer is hidden)." | |
379 | (message "parsing tar file...") | |
380 | (let* ((result '()) | |
381 | (pos 1) | |
382 | (bs (max 1 (- (buffer-size) 1024))) ; always 2+ empty blocks at end. | |
383 | (bs100 (max 1 (/ bs 100))) | |
384 | (tokens nil)) | |
385 | (while (not (eq tokens 'empty-tar-block)) | |
386 | (let* ((hblock (buffer-substring pos (+ pos 512)))) | |
387 | (setq tokens (tokenize-tar-header-block hblock)) | |
388 | (setq pos (+ pos 512)) | |
389 | (message "parsing tar file...%s%%" | |
390 | ;(/ (* pos 100) bs) ; this gets round-off lossage | |
391 | (/ pos bs100) ; this doesn't | |
392 | ) | |
393 | (if (eq tokens 'empty-tar-block) | |
394 | nil | |
395 | (if (null tokens) (error "premature EOF parsing tar file.")) | |
396 | (if (eq (tar-header-link-type tokens) 20) | |
397 | ;; Foo. There's an extra empty block after these. | |
398 | (setq pos (+ pos 512))) | |
399 | (let ((size (tar-header-size tokens))) | |
400 | (if (< size 0) | |
401 | (error "%s has size %s - corrupted." | |
402 | (tar-header-name tokens) size)) | |
403 | ; | |
404 | ; This is just too slow. Don't really need it anyway.... | |
405 | ;(check-tar-header-block-checksum | |
406 | ; hblock (checksum-tar-header-block hblock) | |
407 | ; (tar-header-name tokens)) | |
408 | ||
409 | (setq result (cons (make-tar-desc pos tokens) result)) | |
410 | ||
411 | (if (and (null (tar-header-link-type tokens)) | |
412 | (> size 0)) | |
413 | (setq pos | |
414 | (+ pos 512 (ash (ash (1- size) -9) 9)) ; this works | |
415 | ;(+ pos (+ size (- 512 (rem (1- size) 512)))) ; this doesn't | |
416 | )) | |
417 | )))) | |
418 | (make-local-variable 'tar-parse-info) | |
419 | (setq tar-parse-info (nreverse result))) | |
420 | (save-excursion | |
421 | (goto-char (point-min)) | |
422 | (let ((buffer-read-only nil)) | |
423 | (tar-dolist (tar-desc tar-parse-info) | |
424 | (insert-string | |
425 | (summarize-tar-header-block (tar-desc-tokens tar-desc))) | |
426 | (insert-string "\n")) | |
427 | (make-local-variable 'tar-header-offset) | |
428 | (setq tar-header-offset (point)) | |
429 | (narrow-to-region 1 tar-header-offset) | |
430 | (set-buffer-modified-p nil))) | |
431 | (message "parsing tar file...done.")) | |
432 | ||
433 | ||
434 | (defvar tar-mode-map nil "*Local keymap for tar-mode listings.") | |
435 | ||
436 | (if tar-mode-map | |
437 | nil | |
438 | (setq tar-mode-map (make-keymap)) | |
439 | (suppress-keymap tar-mode-map) | |
440 | (define-key tar-mode-map " " 'tar-next-line) | |
441 | (define-key tar-mode-map "c" 'tar-copy) | |
442 | (define-key tar-mode-map "d" 'tar-flag-deleted) | |
443 | (define-key tar-mode-map "\^D" 'tar-flag-deleted) | |
444 | (define-key tar-mode-map "e" 'tar-extract) | |
445 | (define-key tar-mode-map "f" 'tar-extract) | |
446 | (define-key tar-mode-map "g" 'revert-buffer) | |
447 | (define-key tar-mode-map "h" 'describe-mode) | |
448 | (define-key tar-mode-map "n" 'tar-next-line) | |
449 | (define-key tar-mode-map "\^N" 'tar-next-line) | |
450 | (define-key tar-mode-map "o" 'tar-extract-other-window) | |
451 | (define-key tar-mode-map "\^C" 'tar-copy) | |
452 | (define-key tar-mode-map "p" 'tar-previous-line) | |
453 | (define-key tar-mode-map "\^P" 'tar-previous-line) | |
454 | (define-key tar-mode-map "r" 'tar-rename-entry) | |
455 | (define-key tar-mode-map "u" 'tar-unflag) | |
456 | (define-key tar-mode-map "v" 'tar-view) | |
457 | (define-key tar-mode-map "x" 'tar-expunge) | |
458 | (define-key tar-mode-map "\177" 'tar-unflag-backwards) | |
459 | (define-key tar-mode-map "E" 'tar-extract-other-window) | |
460 | (define-key tar-mode-map "M" 'tar-chmod-entry) | |
461 | (define-key tar-mode-map "G" 'tar-chgrp-entry) | |
462 | (define-key tar-mode-map "O" 'tar-chown-entry) | |
463 | ) | |
464 | ||
465 | ;; tar mode is suitable only for specially formatted data. | |
466 | (put 'tar-mode 'mode-class 'special) | |
467 | (put 'tar-subfile-mode 'mode-class 'special) | |
468 | ||
469 | (defun tar-mode () | |
470 | "Major mode for viewing a tar file as a dired-like listing of its contents. | |
471 | You can move around using the usual cursor motion commands. | |
472 | Letters no longer insert themselves. | |
473 | Type 'e' to pull a file out of the tar file and into its own buffer. | |
474 | Type 'c' to copy an entry from the tar file into another file on disk. | |
475 | ||
476 | If you edit a sub-file of this archive (as with the 'e' command) and | |
477 | save it with Control-X Control-S, the contents of that buffer will be | |
478 | saved back into the tar-file buffer; in this way you can edit a file | |
479 | inside of a tar archive without extracting it and re-archiving it. | |
480 | ||
481 | See also: variables tar-update-datestamp and tar-anal-blocksize. | |
482 | \\{tar-mode-map}" | |
483 | ;; this is not interactive because you shouldn't be turning this | |
484 | ;; mode on and off. You can corrupt things that way. | |
485 | (make-local-variable 'tar-header-offset) | |
486 | (make-local-variable 'tar-parse-info) | |
487 | (make-local-variable 'require-final-newline) | |
488 | (setq require-final-newline nil) ; binary data, dude... | |
489 | (make-local-variable 'revert-buffer-function) | |
490 | (setq revert-buffer-function 'tar-mode-revert) | |
491 | (setq major-mode 'tar-mode) | |
492 | (setq mode-name "Tar") | |
493 | (use-local-map tar-mode-map) | |
494 | (auto-save-mode 0) | |
495 | (widen) | |
496 | (if (and (boundp 'tar-header-offset) tar-header-offset) | |
497 | (narrow-to-region 1 tar-header-offset) | |
498 | (tar-summarize-buffer)) | |
499 | (run-hooks 'tar-mode-hook) | |
500 | ) | |
501 | ||
502 | ||
503 | (defun tar-subfile-mode (p) | |
504 | "Minor mode for editing an element of a tar-file. | |
505 | This mode redefines ^X^S to save the current buffer back into its | |
506 | associated tar-file buffer. You must save that buffer to actually | |
507 | save your changes to disk." | |
508 | (interactive "P") | |
509 | (or (and (boundp 'superior-tar-buffer) superior-tar-buffer) | |
510 | (error "This buffer is not an element of a tar file.")) | |
511 | (or (assq 'tar-subfile-mode minor-mode-alist) | |
512 | (setq minor-mode-alist (append minor-mode-alist | |
513 | (list '(tar-subfile-mode | |
514 | " TarFile"))))) | |
515 | (make-local-variable 'tar-subfile-mode) | |
516 | (setq tar-subfile-mode | |
517 | (if (null p) | |
518 | (not tar-subfile-mode) | |
519 | (> (prefix-numeric-value p) 0))) | |
520 | (cond (tar-subfile-mode | |
521 | ;; copy the local keymap so that we don't accidentally | |
522 | ;; alter a keymap like 'lisp-mode-map' which is shared | |
523 | ;; by all buffers in that mode. | |
524 | (let ((m (current-local-map))) | |
525 | (if m (use-local-map (copy-keymap m)))) | |
526 | (local-set-key "\^X\^S" 'tar-subfile-save-buffer) | |
527 | ;; turn off auto-save. | |
528 | (auto-save-mode nil) | |
529 | (setq buffer-auto-save-file-name nil) | |
530 | (run-hooks 'tar-subfile-mode-hook)) | |
531 | (t (local-set-key "\^X\^S" 'save-buffer))) | |
532 | ) | |
533 | ||
534 | ||
535 | (defun tar-mode-revert (&optional no-autosave no-confirm) | |
536 | "Revert this buffer and turn on tar mode again, to re-compute the | |
537 | directory listing." | |
538 | (setq tar-header-offset nil) | |
539 | (let ((revert-buffer-function nil)) | |
540 | (revert-buffer t no-confirm) | |
541 | (widen)) | |
542 | (tar-mode)) | |
543 | ||
544 | ||
545 | (defun tar-next-line (p) | |
546 | (interactive "p") | |
547 | (forward-line p) | |
548 | (if (eobp) nil (forward-char 36))) | |
549 | ||
550 | (defun tar-previous-line (p) | |
551 | (interactive "p") | |
552 | (tar-next-line (- p))) | |
553 | ||
554 | (defun tar-current-descriptor (&optional noerror) | |
555 | "Returns the tar-descriptor of the current line, or signals an error." | |
556 | ;; I wish lines had plists, like in ZMACS... | |
557 | (or (nth (count-lines (point-min) | |
558 | (save-excursion (beginning-of-line) (point))) | |
559 | tar-parse-info) | |
560 | (if noerror | |
561 | nil | |
562 | (error "This line does not describe a tar-file entry.")))) | |
563 | ||
564 | ||
565 | (defun tar-extract (&optional other-window-p) | |
566 | "*In tar-mode, extract this entry of the tar file into its own buffer." | |
567 | (interactive) | |
568 | (let* ((view-p (eq other-window-p 'view)) | |
569 | (descriptor (tar-current-descriptor)) | |
570 | (tokens (tar-desc-tokens descriptor)) | |
571 | (name (tar-header-name tokens)) | |
572 | (size (tar-header-size tokens)) | |
573 | (link-p (tar-header-link-type tokens)) | |
574 | (start (+ (tar-desc-data-start descriptor) tar-header-offset -1)) | |
575 | (end (+ start size))) | |
576 | (if link-p | |
577 | (error "This is a %s, not a real file." | |
578 | (cond ((eq link-p 5) "directory") | |
579 | ((eq link-p 20) "tar directory header") | |
580 | ((eq link-p 29) "multivolume-continuation") | |
581 | ((eq link-p 35) "sparse entry") | |
582 | ((eq link-p 38) "volume header") | |
583 | (t "link")))) | |
584 | (if (zerop size) (error "This is a zero-length file.")) | |
585 | (let* ((tar-buffer (current-buffer)) | |
586 | (bufname (concat (file-name-nondirectory name) | |
587 | " (" name " in " | |
588 | (file-name-nondirectory (buffer-file-name)) | |
589 | ")")) | |
590 | (read-only-p (or buffer-read-only view-p)) | |
591 | (buffer (get-buffer bufname)) | |
592 | (just-created nil)) | |
593 | (if buffer | |
594 | nil | |
595 | (setq buffer (get-buffer-create bufname)) | |
596 | (setq just-created t) | |
597 | (unwind-protect | |
598 | (progn | |
599 | (widen) | |
600 | (save-excursion | |
601 | (set-buffer buffer) | |
602 | (insert-buffer-substring tar-buffer start end) | |
603 | (goto-char 0) | |
604 | (set-visited-file-name name) ; give it a name to decide mode. | |
605 | (normal-mode) ; pick a mode. | |
606 | (set-visited-file-name nil) ; nuke the name - not meaningful. | |
607 | (rename-buffer bufname) | |
608 | ||
609 | (make-local-variable 'superior-tar-buffer) | |
610 | (make-local-variable 'superior-tar-descriptor) | |
611 | (setq superior-tar-buffer tar-buffer) | |
612 | (setq superior-tar-descriptor descriptor) | |
613 | (tar-subfile-mode 1) | |
614 | ||
615 | (setq buffer-read-only read-only-p) | |
616 | (set-buffer-modified-p nil)) | |
617 | (set-buffer tar-buffer)) | |
618 | (narrow-to-region 1 tar-header-offset))) | |
619 | (if view-p | |
620 | (progn | |
621 | (view-buffer buffer) | |
622 | (and just-created (kill-buffer buffer))) | |
623 | (if other-window-p | |
624 | (switch-to-buffer-other-window buffer) | |
625 | (switch-to-buffer buffer)))))) | |
626 | ||
627 | ||
628 | (defun tar-extract-other-window () | |
629 | "*In tar-mode, extract this entry of the tar file into its own buffer." | |
630 | (interactive) | |
631 | (tar-extract t)) | |
632 | ||
633 | (defun tar-view () | |
634 | "*In tar-mode, view the tar file entry on this line." | |
635 | (interactive) | |
636 | (tar-extract 'view)) | |
637 | ||
638 | ||
639 | (defun tar-read-file-name (&optional prompt) | |
640 | "Calls read-file-name, with the default being the file of the current | |
641 | tar-file descriptor." | |
642 | (or prompt (setq prompt "Copy to: ")) | |
643 | (let* ((default-file (expand-file-name | |
644 | (tar-header-name (tar-desc-tokens | |
645 | (tar-current-descriptor))))) | |
646 | (target (expand-file-name | |
647 | (read-file-name prompt | |
648 | (file-name-directory default-file) | |
649 | default-file nil)))) | |
650 | (if (or (string= "" (file-name-nondirectory target)) | |
651 | (file-directory-p target)) | |
652 | (setq target (concat (if (string-match "/$" target) | |
653 | (substring target 0 (1- (match-end 0))) | |
654 | target) | |
655 | "/" | |
656 | (file-name-nondirectory default-file)))) | |
657 | target)) | |
658 | ||
659 | ||
660 | (defun tar-copy (&optional to-file) | |
661 | "*In tar-mode, extract this entry of the tar file into a file on disk. | |
662 | If TO-FILE is not supplied, it is prompted for, defaulting to the name of | |
663 | the current tar-entry." | |
664 | (interactive (list (tar-read-file-name))) | |
665 | (let* ((descriptor (tar-current-descriptor)) | |
666 | (tokens (tar-desc-tokens descriptor)) | |
667 | (name (tar-header-name tokens)) | |
668 | (size (tar-header-size tokens)) | |
669 | (link-p (tar-header-link-type tokens)) | |
670 | (start (+ (tar-desc-data-start descriptor) tar-header-offset -1)) | |
671 | (end (+ start size))) | |
672 | (if link-p (error "This is a link, not a real file.")) | |
673 | (if (zerop size) (error "This is a zero-length file.")) | |
674 | (let* ((tar-buffer (current-buffer)) | |
675 | buffer) | |
676 | (unwind-protect | |
677 | (progn | |
678 | (setq buffer (generate-new-buffer "*tar-copy-tmp*")) | |
679 | (widen) | |
680 | (save-excursion | |
681 | (set-buffer buffer) | |
682 | (insert-buffer-substring tar-buffer start end) | |
683 | (set-buffer-modified-p nil) ; in case we abort | |
684 | (write-file to-file) | |
685 | (message "Copied tar entry %s to %s" name to-file) | |
686 | (set-buffer tar-buffer))) | |
687 | (narrow-to-region 1 tar-header-offset) | |
688 | (if buffer (kill-buffer buffer))) | |
689 | ))) | |
690 | ||
691 | ||
692 | (defun tar-flag-deleted (p &optional unflag) | |
693 | "*In tar mode, mark this sub-file to be deleted from the tar file. | |
694 | With a prefix argument, mark that many files." | |
695 | (interactive "p") | |
696 | (beginning-of-line) | |
697 | (tar-dotimes (i (if (< p 0) (- p) p)) | |
698 | (if (tar-current-descriptor unflag) ; barf if we're not on an entry-line. | |
699 | (progn | |
700 | (delete-char 1) | |
701 | (insert (if unflag " " "D")))) | |
702 | (forward-line (if (< p 0) -1 1))) | |
703 | (if (eobp) nil (forward-char 36))) | |
704 | ||
705 | (defun tar-unflag (p) | |
706 | "*In tar mode, un-mark this sub-file if it is marked to be deleted. | |
707 | With a prefix argument, un-mark that many files forward." | |
708 | (interactive "p") | |
709 | (tar-flag-deleted p t)) | |
710 | ||
711 | (defun tar-unflag-backwards (p) | |
712 | "*In tar mode, un-mark this sub-file if it is marked to be deleted. | |
713 | With a prefix argument, un-mark that many files backward." | |
714 | (interactive "p") | |
715 | (tar-flag-deleted (- p) t)) | |
716 | ||
717 | ||
718 | (defun tar-expunge-internal () | |
719 | "Expunge the tar-entry specified by the current line." | |
720 | (let* ((descriptor (tar-current-descriptor)) | |
721 | (tokens (tar-desc-tokens descriptor)) | |
722 | (line (tar-desc-data-start descriptor)) | |
723 | (name (tar-header-name tokens)) | |
724 | (size (tar-header-size tokens)) | |
725 | (link-p (tar-header-link-type tokens)) | |
726 | (start (tar-desc-data-start descriptor)) | |
727 | (following-descs (cdr (memq descriptor tar-parse-info)))) | |
728 | (if link-p (setq size 0)) ; size lies for hard-links. | |
729 | ;; | |
730 | ;; delete the current line... | |
731 | (beginning-of-line) | |
732 | (let ((line-start (point))) | |
733 | (end-of-line) (forward-char) | |
734 | (let ((line-len (- (point) line-start))) | |
735 | (delete-region line-start (point)) | |
736 | ;; | |
737 | ;; decrement the header-pointer to be in synch... | |
738 | (setq tar-header-offset (- tar-header-offset line-len)))) | |
739 | ;; | |
740 | ;; delete the data pointer... | |
741 | (setq tar-parse-info (delq descriptor tar-parse-info)) | |
742 | ;; | |
743 | ;; delete the data from inside the file... | |
744 | (widen) | |
745 | (let* ((data-start (+ start tar-header-offset -513)) | |
746 | (data-end (+ data-start 512 (ash (ash (+ size 511) -9) 9)))) | |
747 | (delete-region data-start data-end) | |
748 | ;; | |
749 | ;; and finally, decrement the start-pointers of all following | |
750 | ;; entries in the archive. This is a pig when deleting a bunch | |
751 | ;; of files at once - we could optimize this to only do the | |
752 | ;; iteration over the files that remain, or only iterate up to | |
753 | ;; the next file to be deleted. | |
754 | (let ((data-length (- data-end data-start))) | |
755 | (tar-dolist (desc following-descs) | |
756 | (tar-setf (tar-desc-data-start desc) | |
757 | (- (tar-desc-data-start desc) data-length)))) | |
758 | )) | |
759 | (narrow-to-region 1 tar-header-offset)) | |
760 | ||
761 | ||
762 | (defun tar-expunge (&optional noconfirm) | |
763 | "*In tar-mode, delete all the archived files flagged for deletion. | |
764 | This does not modify the disk image; you must save the tar file itself | |
765 | for this to be permanent." | |
766 | (interactive) | |
767 | (if (or noconfirm | |
768 | (y-or-n-p "expunge files marked for deletion? ")) | |
769 | (let ((n 0)) | |
770 | (save-excursion | |
771 | (goto-char 0) | |
772 | (while (not (eobp)) | |
773 | (if (looking-at "D") | |
774 | (progn (tar-expunge-internal) | |
775 | (setq n (1+ n))) | |
776 | (forward-line 1))) | |
777 | ;; after doing the deletions, add any padding that may be necessary. | |
778 | (tar-pad-to-blocksize) | |
779 | (narrow-to-region 1 tar-header-offset) | |
780 | ) | |
781 | (if (zerop n) | |
782 | (message "nothing to expunge.") | |
783 | (message "%s expunged. Be sure to save this buffer." n))))) | |
784 | ||
785 | ||
786 | (defun tar-clear-modification-flags () | |
787 | "remove the stars at the beginning of each line." | |
788 | (save-excursion | |
789 | (goto-char 0) | |
790 | (while (< (point) tar-header-offset) | |
791 | (if (looking-at "*") | |
792 | (progn (delete-char 1) (insert " "))) | |
793 | (forward-line 1)))) | |
794 | ||
795 | ||
796 | (defun tar-chown-entry (new-uid) | |
797 | "*Change the user-id associated with this entry in the tar file. | |
798 | If this tar file was written by GNU tar, then you will be able to edit | |
799 | the user id as a string; otherwise, you must edit it as a number. | |
800 | You can force editing as a number by calling this with a prefix arg. | |
801 | This does not modify the disk image; you must save the tar file itself | |
802 | for this to be permanent." | |
803 | (interactive (list | |
804 | (let ((tokens (tar-desc-tokens (tar-current-descriptor)))) | |
805 | (if (or current-prefix-arg | |
806 | (not (tar-header-magic tokens))) | |
807 | (let (n) | |
808 | (while (not (numberp (setq n (read-minibuffer | |
809 | "New UID number: " | |
810 | (format "%s" (tar-header-uid tokens))))))) | |
811 | n) | |
812 | (read-string "New UID string: " (tar-header-uname tokens)))))) | |
813 | (cond ((stringp new-uid) | |
814 | (tar-setf (tar-header-uname (tar-desc-tokens (tar-current-descriptor))) | |
815 | new-uid) | |
816 | (tar-alter-one-field tar-uname-offset (concat new-uid "\000"))) | |
817 | (t | |
818 | (tar-setf (tar-header-uid (tar-desc-tokens (tar-current-descriptor))) | |
819 | new-uid) | |
820 | (tar-alter-one-field tar-uid-offset | |
821 | (concat (substring (format "%6o" new-uid) 0 6) "\000 "))))) | |
822 | ||
823 | ||
824 | (defun tar-chgrp-entry (new-gid) | |
825 | "*Change the group-id associated with this entry in the tar file. | |
826 | If this tar file was written by GNU tar, then you will be able to edit | |
827 | the group id as a string; otherwise, you must edit it as a number. | |
828 | You can force editing as a number by calling this with a prefix arg. | |
829 | This does not modify the disk image; you must save the tar file itself | |
830 | for this to be permanent." | |
831 | (interactive (list | |
832 | (let ((tokens (tar-desc-tokens (tar-current-descriptor)))) | |
833 | (if (or current-prefix-arg | |
834 | (not (tar-header-magic tokens))) | |
835 | (let (n) | |
836 | (while (not (numberp (setq n (read-minibuffer | |
837 | "New GID number: " | |
838 | (format "%s" (tar-header-gid tokens))))))) | |
839 | n) | |
840 | (read-string "New GID string: " (tar-header-gname tokens)))))) | |
841 | (cond ((stringp new-gid) | |
842 | (tar-setf (tar-header-gname (tar-desc-tokens (tar-current-descriptor))) | |
843 | new-gid) | |
844 | (tar-alter-one-field tar-gname-offset | |
845 | (concat new-gid "\000"))) | |
846 | (t | |
847 | (tar-setf (tar-header-gid (tar-desc-tokens (tar-current-descriptor))) | |
848 | new-gid) | |
849 | (tar-alter-one-field tar-gid-offset | |
850 | (concat (substring (format "%6o" new-gid) 0 6) "\000 "))))) | |
851 | ||
852 | (defun tar-rename-entry (new-name) | |
853 | "*Change the name associated with this entry in the tar file. | |
854 | This does not modify the disk image; you must save the tar file itself | |
855 | for this to be permanent." | |
856 | (interactive | |
857 | (list (read-string "New name: " | |
858 | (tar-header-name (tar-desc-tokens (tar-current-descriptor)))))) | |
859 | (if (string= "" new-name) (error "zero length name.")) | |
860 | (if (> (length new-name) 98) (error "name too long.")) | |
861 | (tar-setf (tar-header-name (tar-desc-tokens (tar-current-descriptor))) | |
862 | new-name) | |
863 | (tar-alter-one-field 0 | |
864 | (substring (concat new-name (make-string 99 0)) 0 99))) | |
865 | ||
866 | ||
867 | (defun tar-chmod-entry (new-mode) | |
868 | "*Change the protection bits associated with this entry in the tar file. | |
869 | This does not modify the disk image; you must save the tar file itself | |
870 | for this to be permanent." | |
871 | (interactive (list (tar-parse-octal-integer-safe | |
872 | (read-string "New protection (octal): ")))) | |
873 | (tar-setf (tar-header-mode (tar-desc-tokens (tar-current-descriptor))) | |
874 | new-mode) | |
875 | (tar-alter-one-field tar-mode-offset | |
876 | (concat (substring (format "%6o" new-mode) 0 6) "\000 "))) | |
877 | ||
878 | ||
879 | (defun tar-alter-one-field (data-position new-data-string) | |
880 | (let* ((descriptor (tar-current-descriptor)) | |
881 | (tokens (tar-desc-tokens descriptor))) | |
882 | (unwind-protect | |
883 | (save-excursion | |
884 | ;; | |
885 | ;; update the header-line. | |
886 | (beginning-of-line) | |
887 | (let ((p (point))) | |
888 | (forward-line 1) | |
889 | (delete-region p (point)) | |
890 | (insert (summarize-tar-header-block tokens) "\n") | |
891 | (setq tar-header-offset (point-max))) | |
892 | ||
893 | (widen) | |
894 | (let* ((start (+ (tar-desc-data-start descriptor) tar-header-offset -513))) | |
895 | ;; | |
896 | ;; delete the old field and insert a new one. | |
897 | (goto-char (+ start data-position)) | |
898 | (delete-region (point) (+ (point) (length new-data-string))) ; <-- | |
899 | (insert new-data-string) ; <-- | |
900 | ;; | |
901 | ;; compute a new checksum and insert it. | |
902 | (let ((chk (checksum-tar-header-block | |
903 | (buffer-substring start (+ start 512))))) | |
904 | (goto-char (+ start tar-chk-offset)) | |
905 | (delete-region (point) (+ (point) 8)) | |
906 | (insert (format "%6o" chk)) | |
907 | (insert 0) | |
908 | (insert ? ) | |
909 | (tar-setf (tar-header-checksum tokens) chk) | |
910 | ;; | |
911 | ;; ok, make sure we didn't botch it. | |
912 | (check-tar-header-block-checksum | |
913 | (buffer-substring start (+ start 512)) | |
914 | chk (tar-header-name tokens)) | |
915 | ))) | |
916 | (narrow-to-region 1 tar-header-offset)))) | |
917 | ||
918 | ||
3d7fc2fb ER |
919 | (defun tar-octal-time (timeval) |
920 | ;; Format a timestamp as 11 octal digits. Ghod, I hope this works... | |
921 | (let ((hibits (car timeval)) (lobits (car (cdr timeval)))) | |
922 | (insert (format "%05o%01o%05o" | |
923 | (lsh hibits -2) | |
924 | (logior (lsh (logand 3 hibits) 1) (> (logand lobits 32768) 0)) | |
925 | (logand 32767 lobits) | |
926 | )))) | |
927 | ||
aa73f29c RS |
928 | (defun tar-subfile-save-buffer () |
929 | "In tar subfile mode, write this buffer back into its parent tar-file buffer. | |
930 | This doesn't write anything to disk - you must save the parent tar-file buffer | |
931 | to make your changes permanent." | |
932 | (interactive) | |
933 | (if (not (and (boundp 'superior-tar-buffer) superior-tar-buffer)) | |
934 | (error "this buffer has no superior tar file buffer.")) | |
935 | (if (not (and (boundp 'superior-tar-descriptor) superior-tar-descriptor)) | |
936 | (error "this buffer doesn't have an index into its superior tar file!")) | |
937 | (save-excursion | |
938 | (let ((subfile (current-buffer)) | |
939 | (subfile-size (buffer-size)) | |
940 | (descriptor superior-tar-descriptor)) | |
941 | (set-buffer superior-tar-buffer) | |
942 | (let* ((tokens (tar-desc-tokens descriptor)) | |
943 | (start (tar-desc-data-start descriptor)) | |
944 | (name (tar-header-name tokens)) | |
945 | (size (tar-header-size tokens)) | |
946 | (size-pad (ash (ash (+ size 511) -9) 9)) | |
947 | (head (memq descriptor tar-parse-info)) | |
948 | (following-descs (cdr head))) | |
949 | (if (not head) | |
950 | (error "Can't find this tar file entry in its parent tar file!")) | |
951 | (unwind-protect | |
952 | (save-excursion | |
953 | (widen) | |
954 | ;; delete the old data... | |
955 | (let* ((data-start (+ start tar-header-offset -1)) | |
956 | (data-end (+ data-start (ash (ash (+ size 511) -9) 9)))) | |
957 | (delete-region data-start data-end) | |
958 | ;; insert the new data... | |
959 | (goto-char data-start) | |
960 | (insert-buffer subfile) | |
961 | ;; | |
962 | ;; pad the new data out to a multiple of 512... | |
963 | (let ((subfile-size-pad (ash (ash (+ subfile-size 511) -9) 9))) | |
964 | (goto-char (+ data-start subfile-size)) | |
965 | (insert (make-string (- subfile-size-pad subfile-size) 0)) | |
966 | ;; | |
967 | ;; update the data pointer of this and all following files... | |
968 | (tar-setf (tar-header-size tokens) subfile-size) | |
969 | (let ((difference (- subfile-size-pad size-pad))) | |
970 | (tar-dolist (desc following-descs) | |
971 | (tar-setf (tar-desc-data-start desc) | |
972 | (+ (tar-desc-data-start desc) difference)))) | |
973 | ;; | |
974 | ;; Update the size field in the header block. | |
975 | (let ((header-start (- data-start 512))) | |
976 | (goto-char (+ header-start tar-size-offset)) | |
977 | (delete-region (point) (+ (point) 12)) | |
978 | (insert (format "%11o" subfile-size)) | |
979 | (insert ? ) | |
980 | ;; | |
981 | ;; Maybe update the datestamp. | |
982 | (if (not tar-update-datestamp) | |
983 | nil | |
984 | (goto-char (+ header-start tar-time-offset)) | |
985 | (delete-region (point) (+ (point) 12)) | |
3d7fc2fb | 986 | (insert (tar-octal-time (current-time))) |
aa73f29c RS |
987 | (insert ? )) |
988 | ;; | |
989 | ;; compute a new checksum and insert it. | |
990 | (let ((chk (checksum-tar-header-block | |
991 | (buffer-substring header-start data-start)))) | |
992 | (goto-char (+ header-start tar-chk-offset)) | |
993 | (delete-region (point) (+ (point) 8)) | |
994 | (insert (format "%6o" chk)) | |
995 | (insert 0) | |
996 | (insert ? ) | |
997 | (tar-setf (tar-header-checksum tokens) chk))) | |
998 | ;; | |
999 | ;; alter the descriptor-line... | |
1000 | ;; | |
1001 | (let ((position (- (length tar-parse-info) (length head)))) | |
1002 | (goto-char 1) | |
1003 | (next-line position) | |
1004 | (beginning-of-line) | |
1005 | (let ((p (point)) | |
1006 | (m (set-marker (make-marker) tar-header-offset))) | |
1007 | (forward-line 1) | |
1008 | (delete-region p (point)) | |
1009 | (insert-before-markers (summarize-tar-header-block tokens t) "\n") | |
1010 | (setq tar-header-offset (marker-position m))) | |
1011 | ))) | |
1012 | ;; after doing the insertion, add any final padding that may be necessary. | |
1013 | (tar-pad-to-blocksize)) | |
1014 | (narrow-to-region 1 tar-header-offset))) | |
1015 | (set-buffer-modified-p t) ; mark the tar file as modified | |
1016 | (set-buffer subfile) | |
1017 | (set-buffer-modified-p nil) ; mark the tar subfile as unmodified | |
1018 | (message "saved into tar-buffer \"%s\" - remember to save that buffer!" | |
1019 | (buffer-name superior-tar-buffer)) | |
1020 | ))) | |
1021 | ||
1022 | ||
1023 | (defun tar-pad-to-blocksize () | |
1024 | "If we are being anal about tar file blocksizes, fix up the current buffer. | |
1025 | Leaves the region wide." | |
1026 | (if (null tar-anal-blocksize) | |
1027 | nil | |
1028 | (widen) | |
1029 | (let* ((last-desc (nth (1- (length tar-parse-info)) tar-parse-info)) | |
1030 | (start (tar-desc-data-start last-desc)) | |
1031 | (tokens (tar-desc-tokens last-desc)) | |
1032 | (link-p (tar-header-link-type tokens)) | |
1033 | (size (if link-p 0 (tar-header-size tokens))) | |
1034 | (data-end (+ start size)) | |
1035 | (bbytes (ash tar-anal-blocksize 9)) | |
1036 | (pad-to (+ bbytes (* bbytes (/ (1- data-end) bbytes)))) | |
1037 | (buffer-read-only nil) ; ## | |
1038 | ) | |
1039 | ;; If the padding after the last data is too long, delete some; | |
1040 | ;; else insert some until we are padded out to the right number of blocks. | |
1041 | ;; | |
1042 | (goto-char (+ (or tar-header-offset 0) data-end)) | |
1043 | (if (> (1+ (buffer-size)) (+ (or tar-header-offset 0) pad-to)) | |
1044 | (delete-region (+ (or tar-header-offset 0) pad-to) (1+ (buffer-size))) | |
1045 | (insert (make-string (- (+ (or tar-header-offset 0) pad-to) | |
1046 | (1+ (buffer-size))) | |
1047 | 0))) | |
1048 | ))) | |
1049 | ||
1050 | ||
1051 | (defun maybe-write-tar-file () | |
1052 | "Used as a write-file-hook to write tar-files out correctly." | |
1053 | ;; | |
1054 | ;; If the current buffer is in tar-mode and has its header-offset set, | |
1055 | ;; only write out the part of the file after the header-offset. | |
1056 | ;; | |
1057 | (if (and (eq major-mode 'tar-mode) | |
1058 | (and (boundp 'tar-header-offset) tar-header-offset)) | |
1059 | (unwind-protect | |
1060 | (save-excursion | |
1061 | (tar-clear-modification-flags) | |
1062 | (widen) | |
1063 | ;; Doing this here confuses things - the region gets left too wide! | |
1064 | ;; I suppose this is run in a context where changing the buffer is bad. | |
1065 | ;; (tar-pad-to-blocksize) | |
1066 | (write-region tar-header-offset (1+ (buffer-size)) buffer-file-name nil t) | |
1067 | ;; return T because we've written the file. | |
1068 | t) | |
1069 | (narrow-to-region 1 tar-header-offset) | |
1070 | t) | |
1071 | ;; return NIL because we haven't. | |
1072 | nil)) | |
1073 | ||
1074 | \f | |
1075 | ;;; Patch it in. | |
1076 | ||
1077 | (defvar tar-regexp "\\.tar$" | |
1078 | "The regular expression used to identify tar file names.") | |
1079 | ||
1080 | (setq auto-mode-alist | |
1081 | (cons (cons tar-regexp 'tar-mode) auto-mode-alist)) | |
1082 | ||
1083 | (or (boundp 'write-file-hooks) (setq write-file-hooks nil)) | |
1084 | (or (listp write-file-hooks) | |
1085 | (setq write-file-hooks (list write-file-hooks))) | |
1086 | (or (memq 'maybe-write-tar-file write-file-hooks) | |
1087 | (setq write-file-hooks | |
1088 | (cons 'maybe-write-tar-file write-file-hooks))) | |
1089 | ||
1090 | \f | |
1091 | ;;; This is a hack. For files ending in .tar, we want -*- lines to be | |
1092 | ;;; completely ignored - if there is one, it applies to the first file | |
1093 | ;;; in the archive, and not the archive itself! | |
1094 | ||
1095 | (defun tar-normal-mode (&optional find-file) | |
1096 | "Choose the major mode for this buffer automatically. | |
1097 | Also sets up any specified local variables of the file. | |
1098 | Uses the visited file name, the -*- line, and the local variables spec. | |
1099 | ||
1100 | This function is called automatically from `find-file'. In that case, | |
1101 | if `inhibit-local-variables' is non-`nil' we require confirmation before | |
1102 | processing a local variables spec. If you run `normal-mode' explicitly, | |
1103 | confirmation is never required. | |
1104 | ||
1105 | Note that this version of this function has been hacked to interact | |
1106 | correctly with tar files - when visiting a file which matches | |
1107 | 'tar-regexp', the -*- line and local-variables are not examined, | |
1108 | as they would apply to a file within the archive rather than the archive | |
1109 | itself." | |
1110 | (interactive) | |
1111 | (if (and buffer-file-name | |
1112 | (string-match tar-regexp buffer-file-name)) | |
1113 | (tar-mode) | |
1114 | (tar-real-normal-mode find-file))) | |
1115 | ||
1116 | ||
1117 | (if (not (fboundp 'tar-real-normal-mode)) | |
1118 | (fset 'tar-real-normal-mode (symbol-function 'normal-mode))) | |
1119 | (fset 'normal-mode 'tar-normal-mode) | |
1120 | ||
1121 | (provide 'tar-mode) | |
1122 | ||
c88ab9ce | 1123 | ;;; tar-mode.el ends here |