--- /dev/null
+;;; -*- Mode: Emacs-Lisp -*-
+
+;;; File: tar-mode.el
+;;; Description: simple editing of tar files from GNU emacs
+;;; Author: Jamie Zawinski <jwz@lucid.com>
+;;; Created: 4 Apr 1990
+;;; Version: 1.21, 10 Mar 91
+
+;;; Copyright (C) 1990, 1991 Free Software Foundation, Inc.
+;;;
+;;; This file is part of GNU Emacs.
+;;;
+;;; GNU Emacs is free software; you can redistribute it and/or modify
+;;; it under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 1, or (at your option)
+;;; any later version.
+;;;
+;;; GNU Emacs is distributed in the hope that it will be useful,
+;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Emacs; see the file COPYING. If not, write to
+;;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+;;; This package attempts to make dealing with Unix 'tar' archives easier.
+;;; When this code is loaded, visiting a file whose name ends in '.tar' will
+;;; cause the contents of that archive file to be displayed in a Dired-like
+;;; listing. It is then possible to use the customary Dired keybindings to
+;;; extract sub-files from that archive, either by reading them into their own
+;;; editor buffers, or by copying them directly to arbitrary files on disk.
+;;; It is also possible to delete sub-files from within the tar file and write
+;;; the modified archive back to disk, or to edit sub-files within the archive
+;;; and re-insert the modified files into the archive. See the documentation
+;;; string of tar-mode for more info.
+
+;;; To autoload, add this to your .emacs file:
+;;;
+;;; (setq auto-mode-alist (cons '("\\.tar$" . tar-mode) auto-mode-alist))
+;;; (autoload 'tar-mode "tar-mode")
+;;;
+;;; But beware: for certain tar files - those whose very first file has
+;;; a -*- property line - autoloading won't work. See the function
+;;; "tar-normal-mode" to understand why.
+
+;;; This code now understands the extra fields that GNU tar adds to tar files.
+
+;;; This interacts correctly with "uncompress.el" in the Emacs library,
+;;; which you get with
+;;;
+;;; (autoload 'uncompress-while-visiting "uncompress")
+;;; (setq auto-mode-alist (cons '("\\.Z$" . uncompress-while-visiting)
+;;; auto-mode-alist))
+;;;
+;;; Do not attempt to use tar-mode.el with crypt.el, you will lose.
+
+;;; *************** TO DO ***************
+;;;
+;;; o chmod should understand "a+x,og-w".
+;;;
+;;; o It's not possible to add a NEW file to a tar archive; not that
+;;; important, but still...
+;;;
+;;; o In the directory listing, we don't show creation times because I don't
+;;; know how to print an arbitrary date, and I don't really want to have to
+;;; implement decode-universal-time.
+;;;
+;;; o There's code to update the datestamp of edited subfiles, but we set it
+;;; to zero because I don't know how to get the current time as an integer.
+;;;
+;;; o The code is less efficient that it could be - in a lot of places, I
+;;; pull a 512-character string out of the buffer and parse it, when I could
+;;; be parsing it in place, not garbaging a string. Should redo that.
+;;;
+;;; o I'd like a command that searches for a string/regexp in every subfile
+;;; of an archive, where <esc> would leave you in a subfile-edit buffer.
+;;; (Like the Meta-R command of the Zmacs mail reader.)
+;;;
+;;; o Sometimes (but not always) reverting the tar-file buffer does not
+;;; re-grind the listing, and you are staring at the binary tar data.
+;;; Typing 'g' again immediately after that will always revert and re-grind
+;;; it, though. I have no idea why this happens.
+;;;
+;;; o Tar-mode interacts poorly with crypt.el and zcat.el because the tar
+;;; write-file-hook actually writes the file. Instead it should remove the
+;;; header (and conspire to put it back afterwards) so that other write-file
+;;; hooks which frob the buffer have a chance to do their dirty work. There
+;;; might be a problem if the tar write-file-hook does not come *first* on
+;;; the list.
+;;;
+;;; o Block files, sparse files, continuation files, and the various header
+;;; types aren't editable. Actually I don't know that they work at all.
+
+(defvar tar-anal-blocksize 20
+ "*The blocksize of tar files written by Emacs, or nil, meaning don't care.
+The blocksize of a tar file is not really the size of the blocks; rather, it is
+the number of blocks written with one system call. When tarring to a tape,
+this is the size of the *tape* blocks, but when writing to a file, it doesn't
+matter much. The only noticeable difference is that if a tar file does not
+have a blocksize of 20, tar will tell you that; all this really controls is
+how many null padding bytes go on the end of the tar file.")
+
+(defvar tar-update-datestamp nil
+ "*Whether tar-mode should play fast and loose with sub-file datestamps;
+if this is true, then editing and saving a tar file entry back into its
+tar file will update its datestamp. If false, the datestamp is unchanged.
+You may or may not want this - it is good in that you can tell when a file
+in a tar archive has been changed, but it is bad for the same reason that
+editing a file in the tar archive at all is bad - the changed version of
+the file never exists on disk.
+
+## This doesn't work yet because there's no way to get the current time as
+## an integer - if this var is true, then editing a file sets its date to
+## December 31, 1969 (which happens to be what 0 encodes).")
+
+
+\f
+;;; First, duplicate some Common Lisp functions; I used to just (require 'cl)
+;;; but "cl.el" was messing some people up (also it's really big).
+
+(defmacro tar-setf (form val)
+ "A mind-numbingly simple implementation of setf."
+ (let ((mform (macroexpand form (and (boundp 'byte-compile-macro-environment)
+ byte-compile-macro-environment))))
+ (cond ((symbolp mform) (list 'setq mform val))
+ ((not (consp mform)) (error "can't setf %s" form))
+ ((eq (car mform) 'aref)
+ (list 'aset (nth 1 mform) (nth 2 mform) val))
+ ((eq (car mform) 'car)
+ (list 'setcar (nth 1 mform) val))
+ ((eq (car mform) 'cdr)
+ (list 'setcdr (nth 1 mform) val))
+ (t (error "don't know how to setf %s" form)))))
+
+(defmacro tar-dolist (control &rest body)
+ "syntax: (dolist (var-name list-expr &optional return-value) &body body)"
+ (let ((var (car control))
+ (init (car (cdr control)))
+ (val (car (cdr (cdr control)))))
+ (list 'let (list (list '_dolist_iterator_ init))
+ (list 'while '_dolist_iterator_
+ (cons 'let
+ (cons (list (list var '(car _dolist_iterator_)))
+ (append body
+ (list (list 'setq '_dolist_iterator_
+ (list 'cdr '_dolist_iterator_)))))))
+ val)))
+
+(defmacro tar-dotimes (control &rest body)
+ "syntax: (dolist (var-name count-expr &optional return-value) &body body)"
+ (let ((var (car control))
+ (n (car (cdr control)))
+ (val (car (cdr (cdr control)))))
+ (list 'let (list (list '_dotimes_end_ n)
+ (list var 0))
+ (cons 'while
+ (cons (list '< var '_dotimes_end_)
+ (append body
+ (list (list 'setq var (list '1+ var))))))
+ val)))
+
+\f
+;;; down to business.
+
+(defmacro make-tar-header (name mode uid git size date ck lt ln
+ magic uname gname devmaj devmin)
+ (list 'vector name mode uid git size date ck lt ln
+ magic uname gname devmaj devmin))
+
+(defmacro tar-header-name (x) (list 'aref x 0))
+(defmacro tar-header-mode (x) (list 'aref x 1))
+(defmacro tar-header-uid (x) (list 'aref x 2))
+(defmacro tar-header-gid (x) (list 'aref x 3))
+(defmacro tar-header-size (x) (list 'aref x 4))
+(defmacro tar-header-date (x) (list 'aref x 5))
+(defmacro tar-header-checksum (x) (list 'aref x 6))
+(defmacro tar-header-link-type (x) (list 'aref x 7))
+(defmacro tar-header-link-name (x) (list 'aref x 8))
+(defmacro tar-header-magic (x) (list 'aref x 9))
+(defmacro tar-header-uname (x) (list 'aref x 10))
+(defmacro tar-header-gname (x) (list 'aref x 11))
+(defmacro tar-header-dmaj (x) (list 'aref x 12))
+(defmacro tar-header-dmin (x) (list 'aref x 13))
+
+(defmacro make-tar-desc (data-start tokens)
+ (list 'cons data-start tokens))
+
+(defmacro tar-desc-data-start (x) (list 'car x))
+(defmacro tar-desc-tokens (x) (list 'cdr x))
+
+(defconst tar-name-offset 0)
+(defconst tar-mode-offset (+ tar-name-offset 100))
+(defconst tar-uid-offset (+ tar-mode-offset 8))
+(defconst tar-gid-offset (+ tar-uid-offset 8))
+(defconst tar-size-offset (+ tar-gid-offset 8))
+(defconst tar-time-offset (+ tar-size-offset 12))
+(defconst tar-chk-offset (+ tar-time-offset 12))
+(defconst tar-linkp-offset (+ tar-chk-offset 8))
+(defconst tar-link-offset (+ tar-linkp-offset 1))
+;;; GNU-tar specific slots.
+(defconst tar-magic-offset (+ tar-link-offset 100))
+(defconst tar-uname-offset (+ tar-magic-offset 8))
+(defconst tar-gname-offset (+ tar-uname-offset 32))
+(defconst tar-dmaj-offset (+ tar-gname-offset 32))
+(defconst tar-dmin-offset (+ tar-dmaj-offset 8))
+(defconst tar-end-offset (+ tar-dmin-offset 8))
+
+(defun tokenize-tar-header-block (string)
+ "Returns a 'tar-header' structure (a list of name, mode, uid, gid, size,
+write-date, checksum, link-type, and link-name)."
+ (cond ((< (length string) 512) nil)
+ (;(some 'plusp string) ; <-- oops, massive cycle hog!
+ (or (not (= 0 (aref string 0))) ; This will do.
+ (not (= 0 (aref string 101))))
+ (let* ((name-end (1- tar-mode-offset))
+ (link-end (1- tar-magic-offset))
+ (uname-end (1- tar-gname-offset))
+ (gname-end (1- tar-dmaj-offset))
+ (link-p (aref string tar-linkp-offset))
+ (magic-str (substring string tar-magic-offset (1- tar-uname-offset)))
+ (uname-valid-p (or (string= "ustar " magic-str) (string= "GNUtar " magic-str)))
+ name
+ (nulsexp "[^\000]*\000"))
+ (and (string-match nulsexp string tar-name-offset) (setq name-end (min name-end (1- (match-end 0)))))
+ (and (string-match nulsexp string tar-link-offset) (setq link-end (min link-end (1- (match-end 0)))))
+ (and (string-match nulsexp string tar-uname-offset) (setq uname-end (min uname-end (1- (match-end 0)))))
+ (and (string-match nulsexp string tar-gname-offset) (setq gname-end (min gname-end (1- (match-end 0)))))
+ (setq name (substring string tar-name-offset name-end)
+ link-p (if (or (= link-p 0) (= link-p ?0))
+ nil
+ (- link-p ?0)))
+ (if (and (null link-p) (string-match "/$" name)) (setq link-p 5)) ; directory
+ (make-tar-header
+ name
+ (tar-parse-octal-integer string tar-mode-offset (1- tar-uid-offset))
+ (tar-parse-octal-integer string tar-uid-offset (1- tar-gid-offset))
+ (tar-parse-octal-integer string tar-gid-offset (1- tar-size-offset))
+ (tar-parse-octal-integer string tar-size-offset (1- tar-time-offset))
+ (tar-parse-octal-integer string tar-time-offset (1- tar-chk-offset))
+ (tar-parse-octal-integer string tar-chk-offset (1- tar-linkp-offset))
+ link-p
+ (substring string tar-link-offset link-end)
+ uname-valid-p
+ (and uname-valid-p (substring string tar-uname-offset uname-end))
+ (and uname-valid-p (substring string tar-gname-offset gname-end))
+ (tar-parse-octal-integer string tar-dmaj-offset (1- tar-dmin-offset))
+ (tar-parse-octal-integer string tar-dmin-offset (1- tar-end-offset))
+ )))
+ (t 'empty-tar-block)))
+
+
+(defun tar-parse-octal-integer (string &optional start end)
+ "deletes all your files, and then reboots."
+ (if (null start) (setq start 0))
+ (if (null end) (setq end (length string)))
+ (if (= (aref string start) 0)
+ 0
+ (let ((n 0))
+ (while (< start end)
+ (setq n (if (< (aref string start) ?0) n
+ (+ (* n 8) (- (aref string start) 48)))
+ start (1+ start)))
+ n)))
+
+(defun tar-parse-octal-integer-safe (string)
+ (let ((L (length string)))
+ (if (= L 0) (error "empty string"))
+ (tar-dotimes (i L)
+ (if (or (< (aref string i) ?0)
+ (> (aref string i) ?7))
+ (error "'%c' is not an octal digit."))))
+ (tar-parse-octal-integer string))
+
+
+(defun checksum-tar-header-block (string)
+ "Computes and returns a tar-acceptable checksum for this block."
+ (let* ((chk-field-start tar-chk-offset)
+ (chk-field-end (+ chk-field-start 8))
+ (sum 0)
+ (i 0))
+ ;; Add up all of the characters except the ones in the checksum field.
+ ;; Add that field as if it were filled with spaces.
+ (while (< i chk-field-start)
+ (setq sum (+ sum (aref string i))
+ i (1+ i)))
+ (setq i chk-field-end)
+ (while (< i 512)
+ (setq sum (+ sum (aref string i))
+ i (1+ i)))
+ (+ sum (* 32 8))))
+
+(defun check-tar-header-block-checksum (hblock desired-checksum file-name)
+ "Beep and print a warning if the checksum doesn't match."
+ (if (not (= desired-checksum (checksum-tar-header-block hblock)))
+ (progn (beep) (message "Invalid checksum for file %s!" file-name))))
+
+(defun recompute-tar-header-block-checksum (hblock)
+ "Modifies the given string to have a valid checksum field."
+ (let* ((chk (checksum-tar-header-block hblock))
+ (chk-string (format "%6o" chk))
+ (l (length chk-string)))
+ (aset hblock 154 0)
+ (aset hblock 155 32)
+ (tar-dotimes (i l) (aset hblock (- 153 i) (aref chk-string (- l i 1)))))
+ hblock)
+
+
+(defun tar-grind-file-mode (mode string start)
+ "Write a \"-rw--r--r-\" representing MODE into STRING beginning at START."
+ (aset string start (if (zerop (logand 256 mode)) ?- ?r))
+ (aset string (+ start 1) (if (zerop (logand 128 mode)) ?- ?w))
+ (aset string (+ start 2) (if (zerop (logand 64 mode)) ?- ?x))
+ (aset string (+ start 3) (if (zerop (logand 32 mode)) ?- ?r))
+ (aset string (+ start 4) (if (zerop (logand 16 mode)) ?- ?w))
+ (aset string (+ start 5) (if (zerop (logand 8 mode)) ?- ?x))
+ (aset string (+ start 6) (if (zerop (logand 4 mode)) ?- ?r))
+ (aset string (+ start 7) (if (zerop (logand 2 mode)) ?- ?w))
+ (aset string (+ start 8) (if (zerop (logand 1 mode)) ?- ?x))
+ (if (zerop (logand 1024 mode)) nil (aset string (+ start 2) ?s))
+ (if (zerop (logand 2048 mode)) nil (aset string (+ start 5) ?s))
+ string)
+
+(defun summarize-tar-header-block (tar-hblock &optional mod-p)
+ "Returns a line similar to the output of 'tar -vtf'."
+ (let ((name (tar-header-name tar-hblock))
+ (mode (tar-header-mode tar-hblock))
+ (uid (tar-header-uid tar-hblock))
+ (gid (tar-header-gid tar-hblock))
+ (uname (tar-header-uname tar-hblock))
+ (gname (tar-header-gname tar-hblock))
+ (size (tar-header-size tar-hblock))
+ (time (tar-header-date tar-hblock))
+ (ck (tar-header-checksum tar-hblock))
+ (link-p (tar-header-link-type tar-hblock))
+ (link-name (tar-header-link-name tar-hblock))
+ )
+ (let* ((left 11)
+ (namew 8)
+ (groupw 8)
+ (sizew 8)
+ (datew 2)
+ (slash (1- (+ left namew)))
+ (lastdigit (+ slash groupw sizew))
+ (namestart (+ lastdigit datew))
+ (string (make-string (+ namestart (length name) (if link-p (+ 5 (length link-name)) 0)) 32))
+ (type (tar-header-link-type tar-hblock)))
+ (aset string 0 (if mod-p ?* ? ))
+ (aset string 1
+ (cond ((or (eq type nil) (eq type 0)) ?-)
+ ((eq type 1) ?l) ; link
+ ((eq type 2) ?s) ; symlink
+ ((eq type 3) ?c) ; char special
+ ((eq type 4) ?b) ; block special
+ ((eq type 5) ?d) ; directory
+ ((eq type 6) ?p) ; FIFO/pipe
+ ((eq type 20) ?*) ; directory listing
+ ((eq type 29) ?M) ; multivolume continuation
+ ((eq type 35) ?S) ; sparse
+ ((eq type 38) ?V) ; volume header
+ ))
+ (tar-grind-file-mode mode string 2)
+ (setq uid (if (= 0 (length uname)) (int-to-string uid) uname))
+ (setq gid (if (= 0 (length gname)) (int-to-string gid) gname))
+ (setq size (int-to-string size))
+ (tar-dotimes (i (min (1- namew) (length uid))) (aset string (- slash i) (aref uid (- (length uid) i 1))))
+ (aset string (1+ slash) ?/)
+ (tar-dotimes (i (min (1- groupw) (length gid))) (aset string (+ (+ slash 2) i) (aref gid i)))
+ (tar-dotimes (i (min sizew (length size))) (aset string (- lastdigit i) (aref size (- (length size) i 1))))
+ ;; ## bloody hell, how do I print an arbitrary date??
+ (tar-dotimes (i (length name)) (aset string (+ namestart i) (aref name i)))
+ (if (or (eq link-p 1) (eq link-p 2))
+ (progn
+ (tar-dotimes (i 3) (aset string (+ namestart 1 (length name) i) (aref (if (= link-p 1) "==>" "-->") i)))
+ (tar-dotimes (i (length link-name)) (aset string (+ namestart 5 (length name) i) (aref link-name i)))))
+ string)))
+
+
+(defun tar-summarize-buffer ()
+ "Parse the contents of the tar file in the current buffer, and place a
+dired-like listing on the front; then narrow to it, so that only that listing
+is visible (and the real data of the buffer is hidden)."
+ (message "parsing tar file...")
+ (let* ((result '())
+ (pos 1)
+ (bs (max 1 (- (buffer-size) 1024))) ; always 2+ empty blocks at end.
+ (bs100 (max 1 (/ bs 100)))
+ (tokens nil))
+ (while (not (eq tokens 'empty-tar-block))
+ (let* ((hblock (buffer-substring pos (+ pos 512))))
+ (setq tokens (tokenize-tar-header-block hblock))
+ (setq pos (+ pos 512))
+ (message "parsing tar file...%s%%"
+ ;(/ (* pos 100) bs) ; this gets round-off lossage
+ (/ pos bs100) ; this doesn't
+ )
+ (if (eq tokens 'empty-tar-block)
+ nil
+ (if (null tokens) (error "premature EOF parsing tar file."))
+ (if (eq (tar-header-link-type tokens) 20)
+ ;; Foo. There's an extra empty block after these.
+ (setq pos (+ pos 512)))
+ (let ((size (tar-header-size tokens)))
+ (if (< size 0)
+ (error "%s has size %s - corrupted."
+ (tar-header-name tokens) size))
+ ;
+ ; This is just too slow. Don't really need it anyway....
+ ;(check-tar-header-block-checksum
+ ; hblock (checksum-tar-header-block hblock)
+ ; (tar-header-name tokens))
+
+ (setq result (cons (make-tar-desc pos tokens) result))
+
+ (if (and (null (tar-header-link-type tokens))
+ (> size 0))
+ (setq pos
+ (+ pos 512 (ash (ash (1- size) -9) 9)) ; this works
+ ;(+ pos (+ size (- 512 (rem (1- size) 512)))) ; this doesn't
+ ))
+ ))))
+ (make-local-variable 'tar-parse-info)
+ (setq tar-parse-info (nreverse result)))
+ (save-excursion
+ (goto-char (point-min))
+ (let ((buffer-read-only nil))
+ (tar-dolist (tar-desc tar-parse-info)
+ (insert-string
+ (summarize-tar-header-block (tar-desc-tokens tar-desc)))
+ (insert-string "\n"))
+ (make-local-variable 'tar-header-offset)
+ (setq tar-header-offset (point))
+ (narrow-to-region 1 tar-header-offset)
+ (set-buffer-modified-p nil)))
+ (message "parsing tar file...done."))
+
+
+(defvar tar-mode-map nil "*Local keymap for tar-mode listings.")
+
+(if tar-mode-map
+ nil
+ (setq tar-mode-map (make-keymap))
+ (suppress-keymap tar-mode-map)
+ (define-key tar-mode-map " " 'tar-next-line)
+ (define-key tar-mode-map "c" 'tar-copy)
+ (define-key tar-mode-map "d" 'tar-flag-deleted)
+ (define-key tar-mode-map "\^D" 'tar-flag-deleted)
+ (define-key tar-mode-map "e" 'tar-extract)
+ (define-key tar-mode-map "f" 'tar-extract)
+ (define-key tar-mode-map "g" 'revert-buffer)
+ (define-key tar-mode-map "h" 'describe-mode)
+ (define-key tar-mode-map "n" 'tar-next-line)
+ (define-key tar-mode-map "\^N" 'tar-next-line)
+ (define-key tar-mode-map "o" 'tar-extract-other-window)
+ (define-key tar-mode-map "\^C" 'tar-copy)
+ (define-key tar-mode-map "p" 'tar-previous-line)
+ (define-key tar-mode-map "\^P" 'tar-previous-line)
+ (define-key tar-mode-map "r" 'tar-rename-entry)
+ (define-key tar-mode-map "u" 'tar-unflag)
+ (define-key tar-mode-map "v" 'tar-view)
+ (define-key tar-mode-map "x" 'tar-expunge)
+ (define-key tar-mode-map "\177" 'tar-unflag-backwards)
+ (define-key tar-mode-map "E" 'tar-extract-other-window)
+ (define-key tar-mode-map "M" 'tar-chmod-entry)
+ (define-key tar-mode-map "G" 'tar-chgrp-entry)
+ (define-key tar-mode-map "O" 'tar-chown-entry)
+ )
+
+;; tar mode is suitable only for specially formatted data.
+(put 'tar-mode 'mode-class 'special)
+(put 'tar-subfile-mode 'mode-class 'special)
+
+(defun tar-mode ()
+ "Major mode for viewing a tar file as a dired-like listing of its contents.
+You can move around using the usual cursor motion commands.
+Letters no longer insert themselves.
+Type 'e' to pull a file out of the tar file and into its own buffer.
+Type 'c' to copy an entry from the tar file into another file on disk.
+
+If you edit a sub-file of this archive (as with the 'e' command) and
+save it with Control-X Control-S, the contents of that buffer will be
+saved back into the tar-file buffer; in this way you can edit a file
+inside of a tar archive without extracting it and re-archiving it.
+
+See also: variables tar-update-datestamp and tar-anal-blocksize.
+\\{tar-mode-map}"
+ ;; this is not interactive because you shouldn't be turning this
+ ;; mode on and off. You can corrupt things that way.
+ (make-local-variable 'tar-header-offset)
+ (make-local-variable 'tar-parse-info)
+ (make-local-variable 'require-final-newline)
+ (setq require-final-newline nil) ; binary data, dude...
+ (make-local-variable 'revert-buffer-function)
+ (setq revert-buffer-function 'tar-mode-revert)
+ (setq major-mode 'tar-mode)
+ (setq mode-name "Tar")
+ (use-local-map tar-mode-map)
+ (auto-save-mode 0)
+ (widen)
+ (if (and (boundp 'tar-header-offset) tar-header-offset)
+ (narrow-to-region 1 tar-header-offset)
+ (tar-summarize-buffer))
+ (run-hooks 'tar-mode-hook)
+ )
+
+
+(defun tar-subfile-mode (p)
+ "Minor mode for editing an element of a tar-file.
+This mode redefines ^X^S to save the current buffer back into its
+associated tar-file buffer. You must save that buffer to actually
+save your changes to disk."
+ (interactive "P")
+ (or (and (boundp 'superior-tar-buffer) superior-tar-buffer)
+ (error "This buffer is not an element of a tar file."))
+ (or (assq 'tar-subfile-mode minor-mode-alist)
+ (setq minor-mode-alist (append minor-mode-alist
+ (list '(tar-subfile-mode
+ " TarFile")))))
+ (make-local-variable 'tar-subfile-mode)
+ (setq tar-subfile-mode
+ (if (null p)
+ (not tar-subfile-mode)
+ (> (prefix-numeric-value p) 0)))
+ (cond (tar-subfile-mode
+ ;; copy the local keymap so that we don't accidentally
+ ;; alter a keymap like 'lisp-mode-map' which is shared
+ ;; by all buffers in that mode.
+ (let ((m (current-local-map)))
+ (if m (use-local-map (copy-keymap m))))
+ (local-set-key "\^X\^S" 'tar-subfile-save-buffer)
+ ;; turn off auto-save.
+ (auto-save-mode nil)
+ (setq buffer-auto-save-file-name nil)
+ (run-hooks 'tar-subfile-mode-hook))
+ (t (local-set-key "\^X\^S" 'save-buffer)))
+ )
+
+
+(defun tar-mode-revert (&optional no-autosave no-confirm)
+ "Revert this buffer and turn on tar mode again, to re-compute the
+directory listing."
+ (setq tar-header-offset nil)
+ (let ((revert-buffer-function nil))
+ (revert-buffer t no-confirm)
+ (widen))
+ (tar-mode))
+
+
+(defun tar-next-line (p)
+ (interactive "p")
+ (forward-line p)
+ (if (eobp) nil (forward-char 36)))
+
+(defun tar-previous-line (p)
+ (interactive "p")
+ (tar-next-line (- p)))
+
+(defun tar-current-descriptor (&optional noerror)
+ "Returns the tar-descriptor of the current line, or signals an error."
+ ;; I wish lines had plists, like in ZMACS...
+ (or (nth (count-lines (point-min)
+ (save-excursion (beginning-of-line) (point)))
+ tar-parse-info)
+ (if noerror
+ nil
+ (error "This line does not describe a tar-file entry."))))
+
+
+(defun tar-extract (&optional other-window-p)
+ "*In tar-mode, extract this entry of the tar file into its own buffer."
+ (interactive)
+ (let* ((view-p (eq other-window-p 'view))
+ (descriptor (tar-current-descriptor))
+ (tokens (tar-desc-tokens descriptor))
+ (name (tar-header-name tokens))
+ (size (tar-header-size tokens))
+ (link-p (tar-header-link-type tokens))
+ (start (+ (tar-desc-data-start descriptor) tar-header-offset -1))
+ (end (+ start size)))
+ (if link-p
+ (error "This is a %s, not a real file."
+ (cond ((eq link-p 5) "directory")
+ ((eq link-p 20) "tar directory header")
+ ((eq link-p 29) "multivolume-continuation")
+ ((eq link-p 35) "sparse entry")
+ ((eq link-p 38) "volume header")
+ (t "link"))))
+ (if (zerop size) (error "This is a zero-length file."))
+ (let* ((tar-buffer (current-buffer))
+ (bufname (concat (file-name-nondirectory name)
+ " (" name " in "
+ (file-name-nondirectory (buffer-file-name))
+ ")"))
+ (read-only-p (or buffer-read-only view-p))
+ (buffer (get-buffer bufname))
+ (just-created nil))
+ (if buffer
+ nil
+ (setq buffer (get-buffer-create bufname))
+ (setq just-created t)
+ (unwind-protect
+ (progn
+ (widen)
+ (save-excursion
+ (set-buffer buffer)
+ (insert-buffer-substring tar-buffer start end)
+ (goto-char 0)
+ (set-visited-file-name name) ; give it a name to decide mode.
+ (normal-mode) ; pick a mode.
+ (set-visited-file-name nil) ; nuke the name - not meaningful.
+ (rename-buffer bufname)
+
+ (make-local-variable 'superior-tar-buffer)
+ (make-local-variable 'superior-tar-descriptor)
+ (setq superior-tar-buffer tar-buffer)
+ (setq superior-tar-descriptor descriptor)
+ (tar-subfile-mode 1)
+
+ (setq buffer-read-only read-only-p)
+ (set-buffer-modified-p nil))
+ (set-buffer tar-buffer))
+ (narrow-to-region 1 tar-header-offset)))
+ (if view-p
+ (progn
+ (view-buffer buffer)
+ (and just-created (kill-buffer buffer)))
+ (if other-window-p
+ (switch-to-buffer-other-window buffer)
+ (switch-to-buffer buffer))))))
+
+
+(defun tar-extract-other-window ()
+ "*In tar-mode, extract this entry of the tar file into its own buffer."
+ (interactive)
+ (tar-extract t))
+
+(defun tar-view ()
+ "*In tar-mode, view the tar file entry on this line."
+ (interactive)
+ (tar-extract 'view))
+
+
+(defun tar-read-file-name (&optional prompt)
+ "Calls read-file-name, with the default being the file of the current
+tar-file descriptor."
+ (or prompt (setq prompt "Copy to: "))
+ (let* ((default-file (expand-file-name
+ (tar-header-name (tar-desc-tokens
+ (tar-current-descriptor)))))
+ (target (expand-file-name
+ (read-file-name prompt
+ (file-name-directory default-file)
+ default-file nil))))
+ (if (or (string= "" (file-name-nondirectory target))
+ (file-directory-p target))
+ (setq target (concat (if (string-match "/$" target)
+ (substring target 0 (1- (match-end 0)))
+ target)
+ "/"
+ (file-name-nondirectory default-file))))
+ target))
+
+
+(defun tar-copy (&optional to-file)
+ "*In tar-mode, extract this entry of the tar file into a file on disk.
+If TO-FILE is not supplied, it is prompted for, defaulting to the name of
+the current tar-entry."
+ (interactive (list (tar-read-file-name)))
+ (let* ((descriptor (tar-current-descriptor))
+ (tokens (tar-desc-tokens descriptor))
+ (name (tar-header-name tokens))
+ (size (tar-header-size tokens))
+ (link-p (tar-header-link-type tokens))
+ (start (+ (tar-desc-data-start descriptor) tar-header-offset -1))
+ (end (+ start size)))
+ (if link-p (error "This is a link, not a real file."))
+ (if (zerop size) (error "This is a zero-length file."))
+ (let* ((tar-buffer (current-buffer))
+ buffer)
+ (unwind-protect
+ (progn
+ (setq buffer (generate-new-buffer "*tar-copy-tmp*"))
+ (widen)
+ (save-excursion
+ (set-buffer buffer)
+ (insert-buffer-substring tar-buffer start end)
+ (set-buffer-modified-p nil) ; in case we abort
+ (write-file to-file)
+ (message "Copied tar entry %s to %s" name to-file)
+ (set-buffer tar-buffer)))
+ (narrow-to-region 1 tar-header-offset)
+ (if buffer (kill-buffer buffer)))
+ )))
+
+
+(defun tar-flag-deleted (p &optional unflag)
+ "*In tar mode, mark this sub-file to be deleted from the tar file.
+With a prefix argument, mark that many files."
+ (interactive "p")
+ (beginning-of-line)
+ (tar-dotimes (i (if (< p 0) (- p) p))
+ (if (tar-current-descriptor unflag) ; barf if we're not on an entry-line.
+ (progn
+ (delete-char 1)
+ (insert (if unflag " " "D"))))
+ (forward-line (if (< p 0) -1 1)))
+ (if (eobp) nil (forward-char 36)))
+
+(defun tar-unflag (p)
+ "*In tar mode, un-mark this sub-file if it is marked to be deleted.
+With a prefix argument, un-mark that many files forward."
+ (interactive "p")
+ (tar-flag-deleted p t))
+
+(defun tar-unflag-backwards (p)
+ "*In tar mode, un-mark this sub-file if it is marked to be deleted.
+With a prefix argument, un-mark that many files backward."
+ (interactive "p")
+ (tar-flag-deleted (- p) t))
+
+
+(defun tar-expunge-internal ()
+ "Expunge the tar-entry specified by the current line."
+ (let* ((descriptor (tar-current-descriptor))
+ (tokens (tar-desc-tokens descriptor))
+ (line (tar-desc-data-start descriptor))
+ (name (tar-header-name tokens))
+ (size (tar-header-size tokens))
+ (link-p (tar-header-link-type tokens))
+ (start (tar-desc-data-start descriptor))
+ (following-descs (cdr (memq descriptor tar-parse-info))))
+ (if link-p (setq size 0)) ; size lies for hard-links.
+ ;;
+ ;; delete the current line...
+ (beginning-of-line)
+ (let ((line-start (point)))
+ (end-of-line) (forward-char)
+ (let ((line-len (- (point) line-start)))
+ (delete-region line-start (point))
+ ;;
+ ;; decrement the header-pointer to be in synch...
+ (setq tar-header-offset (- tar-header-offset line-len))))
+ ;;
+ ;; delete the data pointer...
+ (setq tar-parse-info (delq descriptor tar-parse-info))
+ ;;
+ ;; delete the data from inside the file...
+ (widen)
+ (let* ((data-start (+ start tar-header-offset -513))
+ (data-end (+ data-start 512 (ash (ash (+ size 511) -9) 9))))
+ (delete-region data-start data-end)
+ ;;
+ ;; and finally, decrement the start-pointers of all following
+ ;; entries in the archive. This is a pig when deleting a bunch
+ ;; of files at once - we could optimize this to only do the
+ ;; iteration over the files that remain, or only iterate up to
+ ;; the next file to be deleted.
+ (let ((data-length (- data-end data-start)))
+ (tar-dolist (desc following-descs)
+ (tar-setf (tar-desc-data-start desc)
+ (- (tar-desc-data-start desc) data-length))))
+ ))
+ (narrow-to-region 1 tar-header-offset))
+
+
+(defun tar-expunge (&optional noconfirm)
+ "*In tar-mode, delete all the archived files flagged for deletion.
+This does not modify the disk image; you must save the tar file itself
+for this to be permanent."
+ (interactive)
+ (if (or noconfirm
+ (y-or-n-p "expunge files marked for deletion? "))
+ (let ((n 0))
+ (save-excursion
+ (goto-char 0)
+ (while (not (eobp))
+ (if (looking-at "D")
+ (progn (tar-expunge-internal)
+ (setq n (1+ n)))
+ (forward-line 1)))
+ ;; after doing the deletions, add any padding that may be necessary.
+ (tar-pad-to-blocksize)
+ (narrow-to-region 1 tar-header-offset)
+ )
+ (if (zerop n)
+ (message "nothing to expunge.")
+ (message "%s expunged. Be sure to save this buffer." n)))))
+
+
+(defun tar-clear-modification-flags ()
+ "remove the stars at the beginning of each line."
+ (save-excursion
+ (goto-char 0)
+ (while (< (point) tar-header-offset)
+ (if (looking-at "*")
+ (progn (delete-char 1) (insert " ")))
+ (forward-line 1))))
+
+
+(defun tar-chown-entry (new-uid)
+ "*Change the user-id associated with this entry in the tar file.
+If this tar file was written by GNU tar, then you will be able to edit
+the user id as a string; otherwise, you must edit it as a number.
+You can force editing as a number by calling this with a prefix arg.
+This does not modify the disk image; you must save the tar file itself
+for this to be permanent."
+ (interactive (list
+ (let ((tokens (tar-desc-tokens (tar-current-descriptor))))
+ (if (or current-prefix-arg
+ (not (tar-header-magic tokens)))
+ (let (n)
+ (while (not (numberp (setq n (read-minibuffer
+ "New UID number: "
+ (format "%s" (tar-header-uid tokens)))))))
+ n)
+ (read-string "New UID string: " (tar-header-uname tokens))))))
+ (cond ((stringp new-uid)
+ (tar-setf (tar-header-uname (tar-desc-tokens (tar-current-descriptor)))
+ new-uid)
+ (tar-alter-one-field tar-uname-offset (concat new-uid "\000")))
+ (t
+ (tar-setf (tar-header-uid (tar-desc-tokens (tar-current-descriptor)))
+ new-uid)
+ (tar-alter-one-field tar-uid-offset
+ (concat (substring (format "%6o" new-uid) 0 6) "\000 ")))))
+
+
+(defun tar-chgrp-entry (new-gid)
+ "*Change the group-id associated with this entry in the tar file.
+If this tar file was written by GNU tar, then you will be able to edit
+the group id as a string; otherwise, you must edit it as a number.
+You can force editing as a number by calling this with a prefix arg.
+This does not modify the disk image; you must save the tar file itself
+for this to be permanent."
+ (interactive (list
+ (let ((tokens (tar-desc-tokens (tar-current-descriptor))))
+ (if (or current-prefix-arg
+ (not (tar-header-magic tokens)))
+ (let (n)
+ (while (not (numberp (setq n (read-minibuffer
+ "New GID number: "
+ (format "%s" (tar-header-gid tokens)))))))
+ n)
+ (read-string "New GID string: " (tar-header-gname tokens))))))
+ (cond ((stringp new-gid)
+ (tar-setf (tar-header-gname (tar-desc-tokens (tar-current-descriptor)))
+ new-gid)
+ (tar-alter-one-field tar-gname-offset
+ (concat new-gid "\000")))
+ (t
+ (tar-setf (tar-header-gid (tar-desc-tokens (tar-current-descriptor)))
+ new-gid)
+ (tar-alter-one-field tar-gid-offset
+ (concat (substring (format "%6o" new-gid) 0 6) "\000 ")))))
+
+(defun tar-rename-entry (new-name)
+ "*Change the name associated with this entry in the tar file.
+This does not modify the disk image; you must save the tar file itself
+for this to be permanent."
+ (interactive
+ (list (read-string "New name: "
+ (tar-header-name (tar-desc-tokens (tar-current-descriptor))))))
+ (if (string= "" new-name) (error "zero length name."))
+ (if (> (length new-name) 98) (error "name too long."))
+ (tar-setf (tar-header-name (tar-desc-tokens (tar-current-descriptor)))
+ new-name)
+ (tar-alter-one-field 0
+ (substring (concat new-name (make-string 99 0)) 0 99)))
+
+
+(defun tar-chmod-entry (new-mode)
+ "*Change the protection bits associated with this entry in the tar file.
+This does not modify the disk image; you must save the tar file itself
+for this to be permanent."
+ (interactive (list (tar-parse-octal-integer-safe
+ (read-string "New protection (octal): "))))
+ (tar-setf (tar-header-mode (tar-desc-tokens (tar-current-descriptor)))
+ new-mode)
+ (tar-alter-one-field tar-mode-offset
+ (concat (substring (format "%6o" new-mode) 0 6) "\000 ")))
+
+
+(defun tar-alter-one-field (data-position new-data-string)
+ (let* ((descriptor (tar-current-descriptor))
+ (tokens (tar-desc-tokens descriptor)))
+ (unwind-protect
+ (save-excursion
+ ;;
+ ;; update the header-line.
+ (beginning-of-line)
+ (let ((p (point)))
+ (forward-line 1)
+ (delete-region p (point))
+ (insert (summarize-tar-header-block tokens) "\n")
+ (setq tar-header-offset (point-max)))
+
+ (widen)
+ (let* ((start (+ (tar-desc-data-start descriptor) tar-header-offset -513)))
+ ;;
+ ;; delete the old field and insert a new one.
+ (goto-char (+ start data-position))
+ (delete-region (point) (+ (point) (length new-data-string))) ; <--
+ (insert new-data-string) ; <--
+ ;;
+ ;; compute a new checksum and insert it.
+ (let ((chk (checksum-tar-header-block
+ (buffer-substring start (+ start 512)))))
+ (goto-char (+ start tar-chk-offset))
+ (delete-region (point) (+ (point) 8))
+ (insert (format "%6o" chk))
+ (insert 0)
+ (insert ? )
+ (tar-setf (tar-header-checksum tokens) chk)
+ ;;
+ ;; ok, make sure we didn't botch it.
+ (check-tar-header-block-checksum
+ (buffer-substring start (+ start 512))
+ chk (tar-header-name tokens))
+ )))
+ (narrow-to-region 1 tar-header-offset))))
+
+
+(defun tar-subfile-save-buffer ()
+ "In tar subfile mode, write this buffer back into its parent tar-file buffer.
+This doesn't write anything to disk - you must save the parent tar-file buffer
+to make your changes permanent."
+ (interactive)
+ (if (not (and (boundp 'superior-tar-buffer) superior-tar-buffer))
+ (error "this buffer has no superior tar file buffer."))
+ (if (not (and (boundp 'superior-tar-descriptor) superior-tar-descriptor))
+ (error "this buffer doesn't have an index into its superior tar file!"))
+ (save-excursion
+ (let ((subfile (current-buffer))
+ (subfile-size (buffer-size))
+ (descriptor superior-tar-descriptor))
+ (set-buffer superior-tar-buffer)
+ (let* ((tokens (tar-desc-tokens descriptor))
+ (start (tar-desc-data-start descriptor))
+ (name (tar-header-name tokens))
+ (size (tar-header-size tokens))
+ (size-pad (ash (ash (+ size 511) -9) 9))
+ (head (memq descriptor tar-parse-info))
+ (following-descs (cdr head)))
+ (if (not head)
+ (error "Can't find this tar file entry in its parent tar file!"))
+ (unwind-protect
+ (save-excursion
+ (widen)
+ ;; delete the old data...
+ (let* ((data-start (+ start tar-header-offset -1))
+ (data-end (+ data-start (ash (ash (+ size 511) -9) 9))))
+ (delete-region data-start data-end)
+ ;; insert the new data...
+ (goto-char data-start)
+ (insert-buffer subfile)
+ ;;
+ ;; pad the new data out to a multiple of 512...
+ (let ((subfile-size-pad (ash (ash (+ subfile-size 511) -9) 9)))
+ (goto-char (+ data-start subfile-size))
+ (insert (make-string (- subfile-size-pad subfile-size) 0))
+ ;;
+ ;; update the data pointer of this and all following files...
+ (tar-setf (tar-header-size tokens) subfile-size)
+ (let ((difference (- subfile-size-pad size-pad)))
+ (tar-dolist (desc following-descs)
+ (tar-setf (tar-desc-data-start desc)
+ (+ (tar-desc-data-start desc) difference))))
+ ;;
+ ;; Update the size field in the header block.
+ (let ((header-start (- data-start 512)))
+ (goto-char (+ header-start tar-size-offset))
+ (delete-region (point) (+ (point) 12))
+ (insert (format "%11o" subfile-size))
+ (insert ? )
+ ;;
+ ;; Maybe update the datestamp.
+ (if (not tar-update-datestamp)
+ nil
+ (goto-char (+ header-start tar-time-offset))
+ (delete-region (point) (+ (point) 12))
+ (insert (format "%11o" 0)) ; ## oops - how to get it??
+ (insert ? ))
+ ;;
+ ;; compute a new checksum and insert it.
+ (let ((chk (checksum-tar-header-block
+ (buffer-substring header-start data-start))))
+ (goto-char (+ header-start tar-chk-offset))
+ (delete-region (point) (+ (point) 8))
+ (insert (format "%6o" chk))
+ (insert 0)
+ (insert ? )
+ (tar-setf (tar-header-checksum tokens) chk)))
+ ;;
+ ;; alter the descriptor-line...
+ ;;
+ (let ((position (- (length tar-parse-info) (length head))))
+ (goto-char 1)
+ (next-line position)
+ (beginning-of-line)
+ (let ((p (point))
+ (m (set-marker (make-marker) tar-header-offset)))
+ (forward-line 1)
+ (delete-region p (point))
+ (insert-before-markers (summarize-tar-header-block tokens t) "\n")
+ (setq tar-header-offset (marker-position m)))
+ )))
+ ;; after doing the insertion, add any final padding that may be necessary.
+ (tar-pad-to-blocksize))
+ (narrow-to-region 1 tar-header-offset)))
+ (set-buffer-modified-p t) ; mark the tar file as modified
+ (set-buffer subfile)
+ (set-buffer-modified-p nil) ; mark the tar subfile as unmodified
+ (message "saved into tar-buffer \"%s\" - remember to save that buffer!"
+ (buffer-name superior-tar-buffer))
+ )))
+
+
+(defun tar-pad-to-blocksize ()
+ "If we are being anal about tar file blocksizes, fix up the current buffer.
+Leaves the region wide."
+ (if (null tar-anal-blocksize)
+ nil
+ (widen)
+ (let* ((last-desc (nth (1- (length tar-parse-info)) tar-parse-info))
+ (start (tar-desc-data-start last-desc))
+ (tokens (tar-desc-tokens last-desc))
+ (link-p (tar-header-link-type tokens))
+ (size (if link-p 0 (tar-header-size tokens)))
+ (data-end (+ start size))
+ (bbytes (ash tar-anal-blocksize 9))
+ (pad-to (+ bbytes (* bbytes (/ (1- data-end) bbytes))))
+ (buffer-read-only nil) ; ##
+ )
+ ;; If the padding after the last data is too long, delete some;
+ ;; else insert some until we are padded out to the right number of blocks.
+ ;;
+ (goto-char (+ (or tar-header-offset 0) data-end))
+ (if (> (1+ (buffer-size)) (+ (or tar-header-offset 0) pad-to))
+ (delete-region (+ (or tar-header-offset 0) pad-to) (1+ (buffer-size)))
+ (insert (make-string (- (+ (or tar-header-offset 0) pad-to)
+ (1+ (buffer-size)))
+ 0)))
+ )))
+
+
+(defun maybe-write-tar-file ()
+ "Used as a write-file-hook to write tar-files out correctly."
+ ;;
+ ;; If the current buffer is in tar-mode and has its header-offset set,
+ ;; only write out the part of the file after the header-offset.
+ ;;
+ (if (and (eq major-mode 'tar-mode)
+ (and (boundp 'tar-header-offset) tar-header-offset))
+ (unwind-protect
+ (save-excursion
+ (tar-clear-modification-flags)
+ (widen)
+ ;; Doing this here confuses things - the region gets left too wide!
+ ;; I suppose this is run in a context where changing the buffer is bad.
+ ;; (tar-pad-to-blocksize)
+ (write-region tar-header-offset (1+ (buffer-size)) buffer-file-name nil t)
+ ;; return T because we've written the file.
+ t)
+ (narrow-to-region 1 tar-header-offset)
+ t)
+ ;; return NIL because we haven't.
+ nil))
+
+\f
+;;; Patch it in.
+
+(defvar tar-regexp "\\.tar$"
+ "The regular expression used to identify tar file names.")
+
+(setq auto-mode-alist
+ (cons (cons tar-regexp 'tar-mode) auto-mode-alist))
+
+(or (boundp 'write-file-hooks) (setq write-file-hooks nil))
+(or (listp write-file-hooks)
+ (setq write-file-hooks (list write-file-hooks)))
+(or (memq 'maybe-write-tar-file write-file-hooks)
+ (setq write-file-hooks
+ (cons 'maybe-write-tar-file write-file-hooks)))
+
+\f
+;;; This is a hack. For files ending in .tar, we want -*- lines to be
+;;; completely ignored - if there is one, it applies to the first file
+;;; in the archive, and not the archive itself!
+
+(defun tar-normal-mode (&optional find-file)
+ "Choose the major mode for this buffer automatically.
+Also sets up any specified local variables of the file.
+Uses the visited file name, the -*- line, and the local variables spec.
+
+This function is called automatically from `find-file'. In that case,
+if `inhibit-local-variables' is non-`nil' we require confirmation before
+processing a local variables spec. If you run `normal-mode' explicitly,
+confirmation is never required.
+
+Note that this version of this function has been hacked to interact
+correctly with tar files - when visiting a file which matches
+'tar-regexp', the -*- line and local-variables are not examined,
+as they would apply to a file within the archive rather than the archive
+itself."
+ (interactive)
+ (if (and buffer-file-name
+ (string-match tar-regexp buffer-file-name))
+ (tar-mode)
+ (tar-real-normal-mode find-file)))
+
+
+(if (not (fboundp 'tar-real-normal-mode))
+ (fset 'tar-real-normal-mode (symbol-function 'normal-mode)))
+(fset 'normal-mode 'tar-normal-mode)
+
+(provide 'tar-mode)
+
HCoop / bpt / emacs.git / commitdiff