;;
;; 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 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.
string)
(tar-parse-octal-integer string))
+(defun tar-new-regular-file-header (filename &optional size time)
+ "Return a Tar header for a regular file.
+The header will lack a proper checksum; use `tar-header-block-checksum'
+to compute one, or request `tar-header-serialize' to do that.
+
+Other tar-mode facilities may also require the data-start header
+field to be set to a valid value.
+
+If SIZE is not given or nil, it defaults to 0.
+If TIME is not given or nil, assume now."
+ (make-tar-header
+ nil
+ filename
+ #o644 0 0 (or size 0)
+ (or time (current-time))
+ nil ; checksum
+ nil nil
+ nil nil nil nil nil))
+
+(defun tar--pad-to (pos)
+ (make-string (+ pos (- (point)) (point-min)) 0))
+
+(defun tar--put-at (pos val &optional fmt mask)
+ (when val
+ (insert (tar--pad-to pos)
+ (if fmt
+ (format fmt (if mask (logand mask val) val))
+ val))))
+
+(defun tar-header-serialize (header &optional update-checksum)
+ "Return the serialization of a Tar HEADER as a string.
+This function calls `tar-header-block-check-checksum' to ensure the
+checksum is correct.
+
+If UPDATE-CHECKSUM is non-nil, update HEADER with the newly-computed
+checksum before doing the check."
+ (with-temp-buffer
+ (set-buffer-multibyte nil)
+ (let ((encoded-name
+ (encode-coding-string (tar-header-name header)
+ tar-file-name-coding-system)))
+ (unless (< (length encoded-name) 99)
+ ;; FIXME: Implement it.
+ (error "Long file name support is not implemented"))
+ (insert encoded-name))
+ (tar--put-at tar-mode-offset (tar-header-mode header) "%6o\0 " #o777777)
+ (tar--put-at tar-uid-offset (tar-header-uid header) "%6o\0 " #o777777)
+ (tar--put-at tar-gid-offset (tar-header-gid header) "%6o\0 " #o777777)
+ (tar--put-at tar-size-offset (tar-header-size header) "%11o ")
+ (insert (tar--pad-to tar-time-offset)
+ (tar-octal-time (tar-header-date header))
+ " ")
+ ;; Omit tar-header-checksum (tar-chk-offset) for now.
+ (tar--put-at tar-linkp-offset (tar-header-link-type header))
+ (tar--put-at tar-link-offset (tar-header-link-name header))
+ (when (tar-header-magic header)
+ (tar--put-at tar-magic-offset (tar-header-magic header))
+ (tar--put-at tar-uname-offset (tar-header-uname header))
+ (tar--put-at tar-gname-offset (tar-header-gname header))
+ (tar--put-at tar-dmaj-offset (tar-header-dmaj header) "%7o\0" #o7777777)
+ (tar--put-at tar-dmin-offset (tar-header-dmin header) "%7o\0" #o7777777))
+ (tar--put-at 512 "")
+ (let ((ck (tar-header-block-checksum (buffer-string))))
+ (goto-char (+ (point-min) tar-chk-offset))
+ (delete-char 8)
+ (insert (format "%6o\0 " ck))
+ (when update-checksum
+ (setf (tar-header-checksum header) ck))
+ (tar-header-block-check-checksum (buffer-string)
+ (tar-header-checksum header)
+ (tar-header-name header)))
+ ;; .
+ (buffer-string)))
+
(defun tar-header-block-checksum (string)
"Compute and return a tar-acceptable checksum for this block."
(define-key map "p" 'tar-previous-line)
(define-key map "\^P" 'tar-previous-line)
(define-key map [up] 'tar-previous-line)
+ (define-key map "I" 'tar-new-entry)
(define-key map "R" 'tar-rename-entry)
(define-key map "u" 'tar-unflag)
(define-key map "v" 'tar-view)
(interactive "p")
(tar-next-line (- arg)))
+(defun tar-current-position ()
+ "Return the `tar-parse-info' index for the current line."
+ (count-lines (point-min) (line-beginning-position)))
+
(defun tar-current-descriptor (&optional noerror)
"Return 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) (line-beginning-position))
+ (or (nth (tar-current-position)
tar-parse-info)
(if noerror
nil
(write-region start end to-file nil nil nil t)))
(message "Copied tar entry %s to %s" name to-file)))
+(defun tar-new-entry (filename &optional index)
+ "Insert a new empty regular file before point."
+ (interactive "*sFile name: ")
+ (let* ((buffer (current-buffer))
+ (index (or index (tar-current-position)))
+ (d-list (and (not (zerop index))
+ (nthcdr (+ -1 index) tar-parse-info)))
+ (pos (if d-list
+ (tar-header-data-end (car d-list))
+ (point-min)))
+ (new-descriptor
+ (tar-new-regular-file-header filename)))
+ ;; Update the data buffer; fill the missing descriptor fields.
+ (with-current-buffer tar-data-buffer
+ (goto-char pos)
+ (insert (tar-header-serialize new-descriptor t))
+ (setf (tar-header-data-start new-descriptor)
+ (copy-marker (point) nil)))
+ ;; Update tar-parse-info.
+ (if d-list
+ (setcdr d-list (cons new-descriptor (cdr d-list)))
+ (setq tar-parse-info (cons new-descriptor tar-parse-info)))
+ ;; Update the listing buffer.
+ (save-excursion
+ (goto-char (point-min))
+ (forward-line index)
+ (let ((inhibit-read-only t))
+ (insert (tar-header-block-summarize new-descriptor) ?\n)))
+ ;; .
+ index))
+
(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."