X-Git-Url: http://git.hcoop.net/bpt/emacs.git/blobdiff_plain/f39c6650e2bc91e8cd323c2fab2ff652fe0f8e8a..f81b71c78b3286cfa1e21f57d7afc729236ba17d:/lisp/hexl.el

diff --git a/lisp/hexl.el b/lisp/hexl.el
index 5fc08177e6..8883338a2e 100644
--- a/lisp/hexl.el
+++ b/lisp/hexl.el
@@ -1,6 +1,6 @@
-;;; hexl.el --- edit a file in a hex dump format using the hexl filter.
+;;; 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, 2001 Free Software Foundation, Inc.
 
 ;; Author: Keith Gabryelski <ag@wheaties.ai.mit.edu>
 ;; Maintainer: FSF
@@ -19,8 +19,9 @@
 ;; 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.
+;; along with GNU Emacs; see the file COPYING.  If not, write to the
+;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
 
 ;;; Commentary:
 
@@ -52,25 +53,52 @@
 ;; vars here
 ;;
 
-(defvar hexl-program "hexl"
-  "The program that will hexlify and de-hexlify its stdin.
-`hexl-program' will always be concatenated with `hexl-options'
-and \"-de\" when dehexlfying a buffer.")
-
-(defvar hexl-iso ""
-  "If your emacs can handle ISO characters, this should be set to
-\"-iso\" otherwise it should be \"\".")
+(defgroup hexl nil
+  "Edit a file in a hex dump format using the hexl filter."
+  :group 'data)
 
-(defvar hexl-options (format "-hex %s" hexl-iso)
-  "Options to hexl-program that suit your needs.")
 
-(defvar hexlify-command
-  (format "%s%s %s" exec-directory hexl-program hexl-options)
-  "The command to use to hexlify a buffer.")
+(defcustom hexl-program "hexl"
+  "The program that will hexlify and dehexlify its stdin.
+`hexl-program' will always be concatenated with `hexl-options'
+and \"-de\" when dehexlifying a buffer."
+  :type 'string
+  :group 'hexl)
 
-(defvar dehexlify-command
-  (format "%s%s -de %s" exec-directory hexl-program hexl-options)
-  "The command to use to unhexlify a buffer.")
+(defcustom hexl-iso ""
+  "If your emacs can handle ISO characters, this should be set to
+\"-iso\" otherwise it should be \"\"."
+  :type 'string
+  :group 'hexl)
+
+(defcustom hexl-options (format "-hex %s" hexl-iso)
+  "Options to hexl-program that suit your needs."
+  :type 'string
+  :group 'hexl)
+
+(defcustom hexlify-command
+  (format "%s %s"
+	  (shell-quote-argument
+	   (expand-file-name hexl-program exec-directory))
+	  hexl-options)
+  "The command to use to hexlify a buffer."
+  :type 'string
+  :group 'hexl)
+
+(defcustom dehexlify-command
+  (format "%s -de %s"
+	  (shell-quote-argument
+	   (expand-file-name hexl-program exec-directory))
+	  hexl-options)
+  "The command to use to unhexlify a buffer."
+  :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.")
@@ -80,13 +108,24 @@ and \"-de\" when dehexlfying a buffer.")
 (defvar hexl-mode-old-local-map)
 (defvar hexl-mode-old-mode-name)
 (defvar hexl-mode-old-major-mode)
+(defvar hexl-mode-old-write-contents-hooks)
+(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)
+
 ;;;###autoload
 (defun hexl-mode (&optional arg)
-  "\\<hexl-mode-map>
-A major mode for editing binary files in hex dump format.
+  "\\<hexl-mode-map>A mode for editing binary files in hex dump format.
+This is not an ordinary major mode; it alters some aspects
+if the current mode's behavior, but not all; also, you can exit
+Hexl mode and return to the previous mode using `hexl-mode-exit'.
 
 This function automatically converts a buffer into the hexl format
 using the function `hexlify-buffer'.
@@ -152,13 +191,42 @@ into the buffer at the current point.
 Note: saving the file with any of the usual Emacs commands
 will actually convert it back to binary format while saving.
 
-You can use \\[hexl-find-file] to visit a file in hexl-mode.
+You can use \\[hexl-find-file] to visit a file in Hexl mode.
 
 \\[describe-bindings] for advanced commands."
   (interactive "p")
-  (if (eq major-mode 'hexl-mode)
-      (error "You are already in hexl mode.")
-    (kill-all-local-variables)
+  (unless (eq major-mode 'hexl-mode)
+    (let ((modified (buffer-modified-p))
+	  (inhibit-read-only t)
+	  (original-point (1- (point)))
+	  max-address)
+      (and (eobp) (not (bobp))
+	   (setq original-point (1- original-point)))
+      (if (not (or (eq arg 1) (not arg)))
+	  ;; if no argument then we guess at hexl-max-address
+          (setq max-address (+ (* (/ (1- (buffer-size)) 68) 16) 15))
+        (setq max-address (1- (buffer-size)))
+	;; If the buffer's EOL type is -dos, we need to account for
+	;; extra CR characters added when hexlify-buffer writes the
+	;; buffer to a file.
+	(when (eq (coding-system-eol-type buffer-file-coding-system) 1)
+	  (setq max-address (+ (count-lines (point-min) (point-max))
+			       max-address))
+	  ;; But if there's no newline at the last line, we are off by
+	  ;; one; adjust.
+	  (or (eq (char-before (point-max)) ?\n)
+	      (setq max-address (1- max-address)))
+	  (setq original-point (+ (count-lines (point-min) (point))
+				  original-point))
+	  (or (bolp) (setq original-point (1- original-point))))
+        (hexlify-buffer)
+        (set-buffer-modified-p modified))
+      (make-local-variable 'hexl-max-address)
+      (setq hexl-max-address max-address)
+      (hexl-goto-address original-point))
+
+    ;; We do not turn off the old major mode; instead we just
+    ;; override most of it.  That way, we can restore it perfectly.
     (make-local-variable 'hexl-mode-old-local-map)
     (setq hexl-mode-old-local-map (current-local-map))
     (use-local-map hexl-mode-map)
@@ -171,29 +239,32 @@ You can use \\[hexl-find-file] to visit a file in hexl-mode.
     (setq hexl-mode-old-major-mode major-mode)
     (setq major-mode 'hexl-mode)
 
+    (make-local-variable 'hexl-mode-old-syntax-table)
+    (setq hexl-mode-old-syntax-table (syntax-table))
+    (set-syntax-table (standard-syntax-table))
+
+    (make-local-variable 'hexl-mode-old-write-contents-hooks)
+    (setq hexl-mode-old-write-contents-hooks write-contents-hooks)
     (make-local-variable 'write-contents-hooks)
     (add-hook 'write-contents-hooks 'hexl-save-buffer)
 
+    (make-local-variable 'hexl-mode-old-require-final-newline)
+    (setq hexl-mode-old-require-final-newline require-final-newline)
+    (make-local-variable 'require-final-newline)
+    (setq require-final-newline nil)
+
+    ;; Add hooks to rehexlify or dehexlify on various events.
     (make-local-hook 'after-revert-hook)
     (add-hook 'after-revert-hook 'hexl-after-revert-hook nil t)
 
-    (make-local-variable 'hexl-max-address)
+    (make-local-hook 'change-major-mode-hook)
+    (add-hook 'change-major-mode-hook 'hexl-maybe-dehexlify-buffer nil t)
 
-    (make-local-variable 'change-major-mode-hook)
-    (add-hook 'change-major-mode-hook 'hexl-maybe-dehexlify-buffer)
-
-    (let ((modified (buffer-modified-p))
-	  (inhibit-read-only t)
-	  (original-point (1- (point))))
-      (if (not (or (eq arg 1) (not arg)))
-	  ;; if no argument then we guess at hexl-max-address
-          (setq hexl-max-address (+ (* (/ (1- (buffer-size)) 68) 16) 15))
-        (setq hexl-max-address (1- (buffer-size)))
-        (hexlify-buffer)
-        (set-buffer-modified-p modified)
-        (hexl-goto-address original-point)))))
+    (if hexl-follow-ascii (hexl-follow-ascii 1)))
+  (run-hooks 'hexl-mode-hook))
 
 (defun hexl-after-revert-hook ()
+  (setq hexl-max-address (1- (buffer-size)))
   (hexlify-buffer)
   (set-buffer-modified-p nil))
 
@@ -216,8 +287,7 @@ You can use \\[hexl-find-file] to visit a file in hexl-mode.
 				   (set-buffer name)
 				   (dehexlify-buffer)
 				   ;; Prevent infinite recursion.
-				   (let ((hexl-in-save-buffer t)
-					 (buffer-file-type t)) ; for ms-dos
+				   (let ((hexl-in-save-buffer t))
 				     (save-buffer))
 				   (setq modified (buffer-modified-p))
 				   (delete-region (point-min) (point-max))
@@ -234,9 +304,7 @@ You can use \\[hexl-find-file] to visit a file in hexl-mode.
   "Edit file FILENAME in hexl-mode.
 Switch to a buffer visiting file FILENAME, creating one in none exists."
   (interactive "fFilename: ")
-  (if (or (eq system-type 'ms-dos) (eq system-type 'windows-nt))
-      (find-file-binary filename)
-    (find-file filename))
+  (find-file-literally filename)
   (if (not (eq major-mode 'hexl-mode))
       (hexl-mode)))
 
@@ -249,11 +317,26 @@ With arg, don't unhexlify buffer."
 	    (inhibit-read-only t)
 	    (original-point (1+ (hexl-current-address))))
 	(dehexlify-buffer)
-	(remove-hook 'write-contents-hook 'hexl-save-buffer)
+	(remove-hook 'write-contents-hooks 'hexl-save-buffer)
 	(set-buffer-modified-p modified)
+	(goto-char original-point)
+	;; Maybe adjust point for the removed CR characters.
+	(when (eq (coding-system-eol-type buffer-file-coding-system) 1)
+	  (setq original-point (- original-point
+				  (count-lines (point-min) (point))))
+	  (or (bobp) (setq original-point (1+ original-point))))
 	(goto-char original-point)))
+
+  (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)
   (setq mode-name hexl-mode-old-mode-name)
   (use-local-map hexl-mode-old-local-map)
+  (set-syntax-table hexl-mode-old-syntax-table)
   (setq major-mode hexl-mode-old-major-mode)
   (force-mode-line-update))
 
@@ -265,36 +348,43 @@ Ask the user for confirmation."
 	    (inhibit-read-only t)
 	    (original-point (1+ (hexl-current-address))))
 	(dehexlify-buffer)
-	(remove-hook 'write-contents-hook 'hexl-save-buffer)
+	(remove-hook 'write-contents-hooks 'hexl-save-buffer)
 	(set-buffer-modified-p modified)
 	(goto-char original-point))))
 
-(defun hexl-current-address ()
+(defun hexl-current-address (&optional validate)
   "Return current hexl-address."
   (interactive)
-  (let ((current-column (- (% (point) 68) 11)) 
+  (let ((current-column (- (% (point) 68) 11))
 	(hexl-address 0))
-    (setq hexl-address (+ (* (/ (point) 68) 16)
-			  (/ (- current-column  (/ current-column 5)) 2)))
+    (if (< current-column 0)
+	(if validate
+	    (error "Point is not on a character in the file")
+	  (setq current-column 0)))
+    (setq hexl-address
+	  (+ (* (/ (point) 68) 16)
+	     (if (>= current-column 41)
+		 (- current-column 41)
+	       (/ (- current-column  (/ current-column 5)) 2))))
+    (when (interactive-p)
+      (message "Current address is %d" hexl-address))
     hexl-address))
 
 (defun hexl-address-to-marker (address)
-  "Return marker for ADDRESS."
+  "Return buffer position for ADDRESS."
   (interactive "nAddress: ")
   (+ (* (/ address 16) 68) 11 (/ (* (% address 16) 5) 2)))
 
 (defun hexl-goto-address (address)
   "Goto hexl-mode (decimal) address ADDRESS.
-
 Signal error if ADDRESS out of range."
   (interactive "nAddress: ")
   (if (or (< address 0) (> address hexl-max-address))
-	  (error "Out of hexl region."))
+	  (error "Out of hexl region"))
   (goto-char (hexl-address-to-marker address)))
 
 (defun hexl-goto-hex-address (hex-address)
   "Go to hexl-mode address (hex string) HEX-ADDRESS.
-
 Signal error if HEX-ADDRESS is out of range."
   (interactive "sHex Address: ")
   (hexl-goto-address (hexl-hex-string-to-integer hex-address)))
@@ -472,26 +562,38 @@ With prefix arg N, puts point N bytes of the way from the true beginning."
   (hexl-scroll-up (- arg)))
 
 (defun hexl-scroll-up (arg)
-  "Scroll hexl buffer window upward ARG lines; or near full window if no ARG."
+  "Scroll hexl buffer window upward ARG lines; or near full window if no ARG.
+If there's no byte at the target address, move to the first or last line."
   (interactive "P")
   (if (null arg)
       (setq arg (1- (window-height)))
     (setq arg (prefix-numeric-value arg)))
-  (let ((movement (* arg 16))
-	(address (hexl-current-address)))
-    (if (or (> (+ address movement) hexl-max-address)
-	    (< (+ address movement) 0))
-	(message "Out of hexl region.")
-      (hexl-goto-address (+ address movement))
-      (recenter 0))))
+  (let* ((movement (* arg 16))
+	 (address (hexl-current-address))
+	 (dest (+ address movement)))
+    (cond
+     ;; If possible, try to stay at the same offset from the beginning
+     ;; of the 16-byte group, even if we move to the first or last
+     ;; group.
+     ((and (> dest hexl-max-address)
+	   (>= (% hexl-max-address 16) (% address 16)))
+      (setq dest (+ (logand hexl-max-address -16) (% address 16))))
+     ((> dest hexl-max-address)
+      (setq dest hexl-max-address))
+     ((< dest 0)
+      (setq dest (% address 16))))
+    (if (/= dest (+ address movement))
+	(message "Out of hexl region."))
+    (hexl-goto-address dest)
+    (recenter 0)))
 
 (defun hexl-beginning-of-1k-page ()
-  "Goto to beginning of 1k boundry."
+  "Go to beginning of 1k boundary."
   (interactive)
   (hexl-goto-address (logand (hexl-current-address) -1024)))
 
 (defun hexl-end-of-1k-page ()
-  "Goto to end of 1k boundry."
+  "Go to end of 1k boundary."
   (interactive)
   (hexl-goto-address (let ((address (logior (hexl-current-address) 1023)))
 		       (if (> address hexl-max-address)
@@ -499,12 +601,12 @@ With prefix arg N, puts point N bytes of the way from the true beginning."
 		       address)))
 
 (defun hexl-beginning-of-512b-page ()
-  "Goto to beginning of 512 byte boundry."
+  "Go to beginning of 512 byte boundary."
   (interactive)
   (hexl-goto-address (logand (hexl-current-address) -512)))
 
 (defun hexl-end-of-512b-page ()
-  "Goto to end of 512 byte boundry."
+  "Go to end of 512 byte boundary."
   (interactive)
   (hexl-goto-address (let ((address (logior (hexl-current-address) 511)))
 		       (if (> address hexl-max-address)
@@ -513,26 +615,42 @@ With prefix arg N, puts point N bytes of the way from the true beginning."
 
 (defun hexl-quoted-insert (arg)
   "Read next input character and insert it.
-Useful for inserting control characters.
-You may also type up to 3 octal digits, to insert a character with that code"
+Useful for inserting control characters and non-ASCII characters given their
+numerical code.
+You may also type octal digits, to insert a character with that code."
   (interactive "p")
-  (hexl-insert-char (read-quoted-char) arg))
+  (hexl-insert-multibyte-char (read-quoted-char) arg))
 
 ;00000000: 0011 2233 4455 6677 8899 aabb ccdd eeff  0123456789ABCDEF
 
 ;;;###autoload
 (defun hexlify-buffer ()
-  "Convert a binary buffer to hexl format."
+  "Convert a binary buffer to hexl format.
+This discards the buffer's undo information."
   (interactive)
-  (let ((binary-process-output nil) ; for Ms-Dos
-	(binary-process-input t))
-    (shell-command-on-region (point-min) (point-max) hexlify-command t)))
+  (and buffer-undo-list
+       (or (y-or-n-p "Converting to hexl format discards undo info; ok? ")
+	   (error "Aborted")))
+  (setq buffer-undo-list nil)
+  ;; Don't decode text in the ASCII part of `hexl' program output.
+  (let ((coding-system-for-read 'raw-text)
+	(coding-system-for-write buffer-file-coding-system)
+	(buffer-undo-list t))
+    (shell-command-on-region (point-min) (point-max) hexlify-command t)
+    (if (> (point) (hexl-address-to-marker hexl-max-address))
+	(hexl-goto-address hexl-max-address))))
 
 (defun dehexlify-buffer ()
-  "Convert a hexl format buffer to binary."
+  "Convert a hexl format buffer to binary.
+This discards the buffer's undo information."
   (interactive)
-  (let ((binary-process-output t) ; for Ms-Dos
-	(binary-process-input nil))
+  (and buffer-undo-list
+       (or (y-or-n-p "Converting from hexl format discards undo info; ok? ")
+	   (error "Aborted")))
+  (setq buffer-undo-list nil)
+  (let ((coding-system-for-write 'raw-text)
+	(coding-system-for-read buffer-file-coding-system)
+	(buffer-undo-list t))
     (shell-command-on-region (point-min) (point-max) dehexlify-command t)))
 
 (defun hexl-char-after-point ()
@@ -552,13 +670,13 @@ You may also type up to 3 octal digits, to insert a character with that code"
     (let ((ch (logior character 32)))
       (if (and (>= ch ?a) (<= ch ?f))
 	  (- ch (- ?a 10))
-	(error (format "Invalid hex digit `%c'." ch))))))
+	(error "Invalid hex digit `%c'" ch)))))
 
 (defun hexl-oct-char-to-integer (character)
   "Take a char and return its value as if it was a octal digit."
   (if (and (>= character ?0) (<= character ?7))
       (- character ?0)
-    (error (format "Invalid octal digit `%c'." character))))
+    (error "Invalid octal digit `%c'" character)))
 
 (defun hexl-printable-character (ch)
   "Return a displayable string for character CH."
@@ -570,153 +688,273 @@ You may also type up to 3 octal digits, to insert a character with that code"
 		     46
 		   ch))))
 
+(defun hexl-insert-multibyte-char (ch num)
+  "Insert a possibly multibyte character CH NUM times.
+
+Non-ASCII characters are first encoded with `buffer-file-coding-system',
+and their encoded form is inserted byte by byte."
+  (let ((charset (char-charset ch))
+	(coding (if (or (null buffer-file-coding-system)
+			;; coding-system-type equals t means undecided.
+			(eq (coding-system-type buffer-file-coding-system) t))
+		    default-buffer-file-coding-system
+		  buffer-file-coding-system)))
+    (cond ((and (> ch 0) (< ch 256))
+	   (hexl-insert-char ch num))
+	  ((eq charset 'unknown)
+	   (error
+	    "0x%x -- invalid character code; use \\[hexl-insert-hex-string]"
+	    ch))
+	  (t
+	   (let ((encoded (encode-coding-char ch coding))
+		 (internal (string-as-unibyte (char-to-string ch)))
+		 internal-hex)
+	     ;; If encode-coding-char returns nil, it means our character
+	     ;; cannot be safely encoded with buffer-file-coding-system.
+	     ;; In that case, we offer to insert the internal representation
+	     ;; of that character, byte by byte.
+	     (when (null encoded)
+	       (setq internal-hex
+		     (mapconcat (function (lambda (c) (format "%x" c)))
+				internal " "))
+	       (if (yes-or-no-p
+		    (format
+		     "Insert char 0x%x's internal representation \"%s\"? "
+		     ch internal-hex))
+		   (setq encoded internal)
+		 (error
+		  "Can't encode `0x%x' with this buffer's coding system; try \\[hexl-insert-hex-string]"
+		  ch)))
+	     (while (> num 0)
+	       (mapc
+		(function (lambda (c) (hexl-insert-char c 1))) encoded)
+	       (setq num (1- num))))))))
+
 (defun hexl-self-insert-command (arg)
-  "Insert this character."
+  "Insert this character.
+Interactively, with a numeric argument, insert this character that many times.
+
+Non-ASCII characters are first encoded with `buffer-file-coding-system',
+and their encoded form is inserted byte by byte."
   (interactive "p")
-  (hexl-insert-char last-command-char arg))
+  (hexl-insert-multibyte-char last-command-char arg))
 
 (defun hexl-insert-char (ch num)
-  "Insert a character in a hexl buffer."
-  (let ((address (hexl-current-address)))
+  "Insert the character CH NUM times in a hexl buffer.
+
+CH must be a unibyte character whose value is between 0 and 255."
+  (if (or (< ch 0) (> ch 255))
+      (error "Invalid character 0x%x -- must be in the range [0..255]"))
+  (let ((address (hexl-current-address t)))
     (while (> num 0)
-      (delete-char 2)
-      (insert (format "%02x" ch))
-      (goto-char
-       (+ (* (/ address 16) 68) 52 (% address 16)))
-      (delete-char 1)
-      (insert (hexl-printable-character ch))
-      (or (eq address hexl-max-address)
-	  (setq address (1+ address)))
-      (hexl-goto-address address)
+      (let ((hex-position
+	     (+ (* (/ address 16) 68)
+		11
+		(* 2 (% address 16))
+		(/ (% address 16) 2)))
+	    (ascii-position
+	     (+ (* (/ address 16) 68) 52 (% address 16)))
+	    at-ascii-position)
+	(if (= (point) ascii-position)
+	    (setq at-ascii-position t))
+	(goto-char hex-position)
+	(delete-char 2)
+	(insert (format "%02x" ch))
+	(goto-char ascii-position)
+	(delete-char 1)
+	(insert (hexl-printable-character ch))
+	(or (eq address hexl-max-address)
+	    (setq address (1+ address)))
+	(hexl-goto-address address)
+	(if at-ascii-position
+	    (progn
+	      (beginning-of-line)
+	      (forward-char 51)
+	      (forward-char (% address 16)))))
       (setq num (1- num)))))
 
 ;; hex conversion
 
 (defun hexl-insert-hex-char (arg)
-  "Insert a ASCII char ARG times at point for a given hexadecimal number."
+  "Insert a character given by its hexadecimal code ARG times at point."
   (interactive "p")
   (let ((num (hexl-hex-string-to-integer (read-string "Hex number: "))))
-    (if (or (> num 255) (< num 0))
-	(error "Hex number out of range.")
-      (hexl-insert-char num arg))))
+    (if (< num 0)
+	(error "Hex number out of range")
+      (hexl-insert-multibyte-char num arg))))
+
+(defun hexl-insert-hex-string (str arg)
+  "Insert hexadecimal string STR at point ARG times.
+Embedded whitespace, dashes, and periods in the string are ignored."
+  (interactive "sHex string: \np")
+  (setq str (replace-regexp-in-string "[- \t.]" "" str))
+  (let ((chars '()))
+    (let ((len (length str))
+	  (idx 0))
+      (if (eq (logand len 1) 1)
+	  (let ((num (hexl-hex-string-to-integer (substring str 0 1))))
+	    (setq chars (cons num chars))
+	    (setq idx 1)))
+      (while (< idx len)
+	(let* ((nidx (+ idx 2))
+	       (num (hexl-hex-string-to-integer (substring str idx nidx))))
+	  (setq chars (cons num chars))
+	  (setq idx nidx))))
+    (setq chars (nreverse chars))
+    (while (> arg 0)
+      (let ((chars chars))
+	(while chars
+	  (hexl-insert-char (car chars) 1)
+	  (setq chars (cdr chars))))
+      (setq arg (- arg 1)))))
 
 (defun hexl-insert-decimal-char (arg)
-  "Insert a ASCII char ARG times at point for a given decimal number."
+  "Insert a character given by its decimal code ARG times at point."
   (interactive "p")
   (let ((num (string-to-int (read-string "Decimal Number: "))))
-    (if (or (> num 255) (< num 0))
-	(error "Decimal number out of range.")
-      (hexl-insert-char num arg))))
+    (if (< num 0)
+	(error "Decimal number out of range")
+      (hexl-insert-multibyte-char num arg))))
 
 (defun hexl-insert-octal-char (arg)
-  "Insert a ASCII char ARG times at point for a given octal number."
+  "Insert a character given by its octal code ARG times at point."
   (interactive "p")
   (let ((num (hexl-octal-string-to-integer (read-string "Octal Number: "))))
-    (if (or (> num 255) (< num 0))
-	(error "Decimal number out of range.")
-      (hexl-insert-char num arg))))
+    (if (< num 0)
+	(error "Decimal number out of range")
+      (hexl-insert-multibyte-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
     nil
-    (setq hexl-mode-map (make-sparse-keymap))
-
-    (define-key hexl-mode-map [left] 'hexl-backward-char)
-    (define-key hexl-mode-map [right] 'hexl-forward-char)
-    (define-key hexl-mode-map [up] 'hexl-previous-line)
-    (define-key hexl-mode-map [down] 'hexl-next-line)
-    (define-key hexl-mode-map [M-left] 'hexl-backward-short)
-    (define-key hexl-mode-map [M-right] 'hexl-forward-short)
-    (define-key hexl-mode-map [next] 'hexl-scroll-up)
-    (define-key hexl-mode-map [prev] 'hexl-scroll-down)
-
-    (define-key hexl-mode-map "\C-a" 'hexl-beginning-of-line)
-    (define-key hexl-mode-map "\C-b" 'hexl-backward-char)
-    (define-key hexl-mode-map "\C-d" 'undefined)
-    (define-key hexl-mode-map "\C-e" 'hexl-end-of-line)
-    (define-key hexl-mode-map "\C-f" 'hexl-forward-char)
-
-    (if (not (eq (key-binding (char-to-string help-char)) 'help-command))
-	(define-key hexl-mode-map (char-to-string help-char) 'undefined))
-
-    (define-key hexl-mode-map "\C-i" 'hexl-self-insert-command)
-    (define-key hexl-mode-map "\C-j" 'hexl-self-insert-command)
-    (define-key hexl-mode-map "\C-k" 'undefined)
-    (define-key hexl-mode-map "\C-m" 'hexl-self-insert-command)
-    (define-key hexl-mode-map "\C-n" 'hexl-next-line)
-    (define-key hexl-mode-map "\C-o" 'undefined)
-    (define-key hexl-mode-map "\C-p" 'hexl-previous-line)
-    (define-key hexl-mode-map "\C-q" 'hexl-quoted-insert)
-    (define-key hexl-mode-map "\C-t" 'undefined)
-    (define-key hexl-mode-map "\C-v" 'hexl-scroll-up)
-    (define-key hexl-mode-map "\C-w" 'undefined)
-    (define-key hexl-mode-map "\C-y" 'undefined)
-
-    (let ((ch 32))
-      (while (< ch 127)
-	(define-key hexl-mode-map (format "%c" ch) 'hexl-self-insert-command)
-	(setq ch (1+ ch))))
-
-    (define-key hexl-mode-map "\e\C-a" 'hexl-beginning-of-512b-page)
-    (define-key hexl-mode-map "\e\C-b" 'hexl-backward-short)
-    (define-key hexl-mode-map "\e\C-c" 'undefined)
-    (define-key hexl-mode-map "\e\C-d" 'hexl-insert-decimal-char)
-    (define-key hexl-mode-map "\e\C-e" 'hexl-end-of-512b-page)
-    (define-key hexl-mode-map "\e\C-f" 'hexl-forward-short)
-    (define-key hexl-mode-map "\e\C-g" 'undefined)
-    (define-key hexl-mode-map "\e\C-h" 'undefined)
-    (define-key hexl-mode-map "\e\C-i" 'undefined)
-    (define-key hexl-mode-map "\e\C-j" 'undefined)
-    (define-key hexl-mode-map "\e\C-k" 'undefined)
-    (define-key hexl-mode-map "\e\C-l" 'undefined)
-    (define-key hexl-mode-map "\e\C-m" 'undefined)
-    (define-key hexl-mode-map "\e\C-n" 'undefined)
-    (define-key hexl-mode-map "\e\C-o" 'hexl-insert-octal-char)
-    (define-key hexl-mode-map "\e\C-p" 'undefined)
-    (define-key hexl-mode-map "\e\C-q" 'undefined)
-    (define-key hexl-mode-map "\e\C-r" 'undefined)
-    (define-key hexl-mode-map "\e\C-s" 'undefined)
-    (define-key hexl-mode-map "\e\C-t" 'undefined)
-    (define-key hexl-mode-map "\e\C-u" 'undefined)
-
-    (define-key hexl-mode-map "\e\C-w" 'undefined)
-    (define-key hexl-mode-map "\e\C-x" 'hexl-insert-hex-char)
-    (define-key hexl-mode-map "\e\C-y" 'undefined)
-
-    (define-key hexl-mode-map "\ea" 'undefined)
-    (define-key hexl-mode-map "\eb" 'hexl-backward-word)
-    (define-key hexl-mode-map "\ec" 'undefined)
-    (define-key hexl-mode-map "\ed" 'undefined)
-    (define-key hexl-mode-map "\ee" 'undefined)
-    (define-key hexl-mode-map "\ef" 'hexl-forward-word)
-    (define-key hexl-mode-map "\eg" 'hexl-goto-hex-address)
-    (define-key hexl-mode-map "\eh" 'undefined)
-    (define-key hexl-mode-map "\ei" 'undefined)
-    (define-key hexl-mode-map "\ej" 'hexl-goto-address)
-    (define-key hexl-mode-map "\ek" 'undefined)
-    (define-key hexl-mode-map "\el" 'undefined)
-    (define-key hexl-mode-map "\em" 'undefined)
-    (define-key hexl-mode-map "\en" 'undefined)
-    (define-key hexl-mode-map "\eo" 'undefined)
-    (define-key hexl-mode-map "\ep" 'undefined)
-    (define-key hexl-mode-map "\eq" 'undefined)
-    (define-key hexl-mode-map "\er" 'undefined)
-    (define-key hexl-mode-map "\es" 'undefined)
-    (define-key hexl-mode-map "\et" 'undefined)
-    (define-key hexl-mode-map "\eu" 'undefined)
-    (define-key hexl-mode-map "\ev" 'hexl-scroll-down)
-    (define-key hexl-mode-map "\ey" 'undefined)
-    (define-key hexl-mode-map "\ez" 'undefined)
-    (define-key hexl-mode-map "\e<" 'hexl-beginning-of-buffer)
-    (define-key hexl-mode-map "\e>" 'hexl-end-of-buffer)
-
-    (define-key hexl-mode-map "\C-c\C-c" 'hexl-mode-exit)
-
-    (define-key hexl-mode-map "\C-x[" 'hexl-beginning-of-1k-page)
-    (define-key hexl-mode-map "\C-x]" 'hexl-end-of-1k-page)
-    (define-key hexl-mode-map "\C-x\C-p" 'undefined)
-    (define-key hexl-mode-map "\C-x\C-s" 'hexl-save-buffer)
-    (define-key hexl-mode-map "\C-x\C-t" 'undefined))
+  (setq hexl-mode-map (make-keymap))
+  ;; Make all self-inserting keys go through hexl-self-insert-command,
+  ;; because we need to convert them to unibyte characters before
+  ;; inserting them into the buffer.
+  (substitute-key-definition 'self-insert-command 'hexl-self-insert-command
+			     hexl-mode-map (current-global-map))
+
+  (define-key hexl-mode-map [left] 'hexl-backward-char)
+  (define-key hexl-mode-map [right] 'hexl-forward-char)
+  (define-key hexl-mode-map [up] 'hexl-previous-line)
+  (define-key hexl-mode-map [down] 'hexl-next-line)
+  (define-key hexl-mode-map [M-left] 'hexl-backward-short)
+  (define-key hexl-mode-map [M-right] 'hexl-forward-short)
+  (define-key hexl-mode-map [next] 'hexl-scroll-up)
+  (define-key hexl-mode-map [prior] 'hexl-scroll-down)
+  (define-key hexl-mode-map [home] 'hexl-beginning-of-line)
+  (define-key hexl-mode-map [end] 'hexl-end-of-line)
+  (define-key hexl-mode-map [C-home] 'hexl-beginning-of-buffer)
+  (define-key hexl-mode-map [C-end] 'hexl-end-of-buffer)
+  (define-key hexl-mode-map [deletechar] 'undefined)
+  (define-key hexl-mode-map [deleteline] 'undefined)
+  (define-key hexl-mode-map [insertline] 'undefined)
+  (define-key hexl-mode-map [S-delete] 'undefined)
+  (define-key hexl-mode-map "\177" 'undefined)
+
+  (define-key hexl-mode-map "\C-a" 'hexl-beginning-of-line)
+  (define-key hexl-mode-map "\C-b" 'hexl-backward-char)
+  (define-key hexl-mode-map "\C-d" 'undefined)
+  (define-key hexl-mode-map "\C-e" 'hexl-end-of-line)
+  (define-key hexl-mode-map "\C-f" 'hexl-forward-char)
+
+  (if (not (eq (key-binding (char-to-string help-char)) 'help-command))
+      (define-key hexl-mode-map (char-to-string help-char) 'undefined))
+
+  (define-key hexl-mode-map "\C-k" 'undefined)
+  (define-key hexl-mode-map "\C-n" 'hexl-next-line)
+  (define-key hexl-mode-map "\C-o" 'undefined)
+  (define-key hexl-mode-map "\C-p" 'hexl-previous-line)
+  (define-key hexl-mode-map "\C-q" 'hexl-quoted-insert)
+  (define-key hexl-mode-map "\C-t" 'undefined)
+  (define-key hexl-mode-map "\C-v" 'hexl-scroll-up)
+  (define-key hexl-mode-map "\C-w" 'undefined)
+  (define-key hexl-mode-map "\C-y" 'undefined)
+
+  (fset 'hexl-ESC-prefix (copy-keymap 'ESC-prefix))
+  (define-key hexl-mode-map "\e" 'hexl-ESC-prefix)
+  (define-key hexl-mode-map "\e\C-a" 'hexl-beginning-of-512b-page)
+  (define-key hexl-mode-map "\e\C-b" 'hexl-backward-short)
+  (define-key hexl-mode-map "\e\C-d" 'hexl-insert-decimal-char)
+  (define-key hexl-mode-map "\e\C-e" 'hexl-end-of-512b-page)
+  (define-key hexl-mode-map "\e\C-f" 'hexl-forward-short)
+  (define-key hexl-mode-map "\e\C-i" 'undefined)
+  (define-key hexl-mode-map "\e\C-j" 'undefined)
+  (define-key hexl-mode-map "\e\C-k" 'undefined)
+  (define-key hexl-mode-map "\e\C-o" 'hexl-insert-octal-char)
+  (define-key hexl-mode-map "\e\C-q" 'undefined)
+  (define-key hexl-mode-map "\e\C-t" 'undefined)
+  (define-key hexl-mode-map "\e\C-x" 'hexl-insert-hex-char)
+  (define-key hexl-mode-map "\eb" 'hexl-backward-word)
+  (define-key hexl-mode-map "\ec" 'undefined)
+  (define-key hexl-mode-map "\ed" 'undefined)
+  (define-key hexl-mode-map "\ef" 'hexl-forward-word)
+  (define-key hexl-mode-map "\eg" 'hexl-goto-hex-address)
+  (define-key hexl-mode-map "\ei" 'undefined)
+  (define-key hexl-mode-map "\ej" 'hexl-goto-address)
+  (define-key hexl-mode-map "\ek" 'undefined)
+  (define-key hexl-mode-map "\el" 'undefined)
+  (define-key hexl-mode-map "\eq" 'undefined)
+  (define-key hexl-mode-map "\es" 'undefined)
+  (define-key hexl-mode-map "\et" 'undefined)
+  (define-key hexl-mode-map "\eu" 'undefined)
+  (define-key hexl-mode-map "\ev" 'hexl-scroll-down)
+  (define-key hexl-mode-map "\ey" 'undefined)
+  (define-key hexl-mode-map "\ez" 'undefined)
+  (define-key hexl-mode-map "\e<" 'hexl-beginning-of-buffer)
+  (define-key hexl-mode-map "\e>" 'hexl-end-of-buffer)
+
+  (fset 'hexl-C-c-prefix (copy-keymap mode-specific-map))
+  (define-key hexl-mode-map "\C-c" 'hexl-C-c-prefix)
+  (define-key hexl-mode-map "\C-c\C-c" 'hexl-mode-exit)
+
+  (fset 'hexl-C-x-prefix (copy-keymap 'Control-X-prefix))
+  (define-key hexl-mode-map "\C-x" 'hexl-C-x-prefix)
+  (define-key hexl-mode-map "\C-x[" 'hexl-beginning-of-1k-page)
+  (define-key hexl-mode-map "\C-x]" 'hexl-end-of-1k-page)
+  (define-key hexl-mode-map "\C-x\C-p" 'undefined)
+  (define-key hexl-mode-map "\C-x\C-s" 'hexl-save-buffer)
+  (define-key hexl-mode-map "\C-x\C-t" 'undefined))
+
+(provide 'hexl)
 
 ;;; hexl.el ends here