;;; hexl.el --- edit a file in a hex dump format using the hexl filter.
-;; Copyright (C) 1989, 1994 Free Software Foundation, Inc.
+;; Copyright (C) 1989, 1994, 1998 Free Software Foundation, Inc.
;; Author: Keith Gabryelski <ag@wheaties.ai.mit.edu>
;; Maintainer: FSF
:type 'string
:group 'hexl)
+(defcustom hexl-follow-ascii t
+ "If non-nil then highlight the ASCII character corresponding to point."
+ :type 'boolean
+ :group 'hexl
+ :version "20.3")
+
(defvar hexl-max-address 0
"Maximum offset into hexl buffer.")
(defvar hexl-mode-old-require-final-newline)
(defvar hexl-mode-old-syntax-table)
+(defvar hexl-ascii-overlay nil
+ "Overlay used to highlight ASCII element corresponding to current point.")
+(make-variable-buffer-local 'hexl-ascii-overlay)
+
;; routines
(put 'hexl-mode 'mode-class 'special)
(add-hook 'after-revert-hook 'hexl-after-revert-hook nil t)
(make-local-hook 'change-major-mode-hook)
- (add-hook 'change-major-mode-hook 'hexl-maybe-dehexlify-buffer nil t))
+ (add-hook 'change-major-mode-hook 'hexl-maybe-dehexlify-buffer nil t)
+
+ (if hexl-follow-ascii (hexl-follow-ascii 1)))
(run-hooks 'hexl-mode-hook))
(defun hexl-after-revert-hook ()
(remove-hook 'after-revert-hook 'hexl-after-revert-hook t)
(remove-hook 'change-major-mode-hook 'hexl-maybe-dehexlify-buffer t)
+ (remove-hook 'post-command-hook 'hexl-follow-ascii-find t)
+ (setq hexl-ascii-overlay nil)
(setq write-contents-hooks hexl-mode-old-write-contents-hooks)
(setq require-final-newline hexl-mode-old-require-final-newline)
(or (y-or-n-p "Converting to hexl format discards undo info; ok? ")
(error "Aborted")))
(setq buffer-undo-list nil)
- (let ((binary-process-output nil) ; for Ms-Dos
- (binary-process-input buffer-file-type)
+ ;; Don't decode text in the ASCII part of `hexl' program output.
+ (let ((coding-system-for-read 'raw-text)
;; If the buffer was read with EOL conversions, be sure to use the
;; same conversions when passing the region to the `hexl' program.
(coding-system-for-write
(or (y-or-n-p "Converting from hexl format discards undo info; ok? ")
(error "Aborted")))
(setq buffer-undo-list nil)
- (let ((binary-process-output buffer-file-type) ; for Ms-Dos
- (binary-process-input nil)
- (coding-system-for-read 'raw-text)
+ (let ((coding-system-for-write 'raw-text)
+ (coding-system-for-read
+ (let ((eol-type (coding-system-eol-type buffer-file-coding-system)))
+ (cond ((eq eol-type 1)
+ 'raw-text-dos)
+ ((eq eol-type 2)
+ 'raw-text-mac)
+ ((eq eol-type 0)
+ 'raw-text-unix)
+ (t 'no-conversion))))
(buffer-undo-list t))
(shell-command-on-region (point-min) (point-max) dehexlify-command t)))
(error "Decimal number out of range")
(hexl-insert-char num arg))))
+(defun hexl-follow-ascii (&optional arg)
+ "Toggle following ASCII in Hexl buffers.
+With prefix ARG, turn on following if and only if ARG is positive.
+When following is enabled, the ASCII character corresponding to the
+element under the point is highlighted.
+Customize the variable `hexl-follow-ascii' to disable this feature."
+ (interactive "P")
+ (let ((on-p (if arg
+ (> (prefix-numeric-value arg) 0)
+ (not hexl-ascii-overlay))))
+
+ (make-local-hook 'post-command-hook)
+
+ (if on-p
+ ;; turn it on
+ (if (not hexl-ascii-overlay)
+ (progn
+ (setq hexl-ascii-overlay (make-overlay 1 1)
+ hexl-follow-ascii t)
+ (overlay-put hexl-ascii-overlay 'face 'highlight)
+ (add-hook 'post-command-hook 'hexl-follow-ascii-find nil t)))
+ ;; turn it off
+ (if hexl-ascii-overlay
+ (progn
+ (delete-overlay hexl-ascii-overlay)
+ (setq hexl-ascii-overlay nil
+ hexl-follow-ascii nil)
+ (remove-hook 'post-command-hook 'hexl-follow-ascii-find t)
+ )))))
+
+(defun hexl-follow-ascii-find ()
+ "Find and highlight the ASCII element corresponding to current point."
+ (let ((pos (+ 51
+ (- (point) (current-column))
+ (mod (hexl-current-address) 16))))
+ (move-overlay hexl-ascii-overlay pos (1+ pos))
+ ))
+
;; startup stuff.
(if hexl-mode-map