lisp/hexl.el

   1 ;;; hexl.el --- edit a file in a hex dump format using the hexl filter
   2
   3 ;; Copyright (C) 1989, 1994, 1998, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
   4
   5 ;; Author: Keith Gabryelski <ag@wheaties.ai.mit.edu>
   6 ;; Maintainer: FSF
   7 ;; Keywords: data
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software; you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation; either version 2, or (at your option)
  14 ;; any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  24 ;; Boston, MA 02111-1307, USA.
  25
  26 ;;; Commentary:
  27
  28 ;; This package implements a major mode for editing binary files.  It uses
  29 ;; a program called hexl, supplied with the GNU Emacs distribution, that
  30 ;; can filter a binary into an editable format or from the format back into
  31 ;; binary.  For full instructions, invoke `hexl-mode' on an empty buffer and
  32 ;; do M-x `describe-mode'.
  33 ;;
  34 ;; NOTE: Remember to change `hexl-program' or `hexl-options' if needed.
  35 ;;
  36 ;; Currently hexl only supports big endian hex output with 16 bit
  37 ;; grouping.
  38 ;;
  39 ;; -iso in `hexl-options' will allow iso characters to display in the
  40 ;; ASCII region of the screen (if your emacs supports this) instead of
  41 ;; changing them to dots.
  42
  43 ;;; Code:
  44
  45 (require 'eldoc)
  46
  47 ;;
  48 ;; vars here
  49 ;;
  50
  51 (defgroup hexl nil
  52   "Edit a file in a hex dump format using the hexl filter."
  53   :group 'data)
  54
  55
  56 (defcustom hexl-program "hexl"
  57   "The program that will hexlify and dehexlify its stdin.
  58 `hexl-program' will always be concatenated with `hexl-options'
  59 and \"-de\" when dehexlifying a buffer."
  60   :type 'string
  61   :group 'hexl)
  62
  63 (defcustom hexl-iso ""
  64   "If your emacs can handle ISO characters, this should be set to
  65 \"-iso\" otherwise it should be \"\"."
  66   :type 'string
  67   :group 'hexl)
  68
  69 (defcustom hexl-options (format "-hex %s" hexl-iso)
  70   "Space separated options to `hexl-program' that suit your needs.
  71 Quoting cannot be used, so the arguments cannot themselves contain spaces."
  72   :type 'string
  73   :group 'hexl)
  74
  75 (defcustom hexl-follow-ascii t
  76   "If non-nil then highlight the ASCII character corresponding to point."
  77   :type 'boolean
  78   :group 'hexl
  79   :version "20.3")
  80
  81 (defcustom hexl-mode-hook '(hexl-follow-line hexl-activate-ruler)
  82   "Normal hook run when entering Hexl mode."
  83   :type 'hook
  84   :options '(hexl-follow-line hexl-activate-ruler turn-on-eldoc-mode)
  85   :group 'hexl)
  86
  87 (defface hexl-address-area
  88   '((t (:inherit header-line)))
  89   "Face used in address are of hexl-mode buffer."
  90   :group 'hexl)
  91
  92 (defface hexl-ascii-area
  93   '((t (:inherit header-line)))
  94   "Face used in ascii are of hexl-mode buffer."
  95   :group 'hexl)
  96
  97 (defvar hexl-max-address 0
  98   "Maximum offset into hexl buffer.")
  99
 100 (defvar hexl-mode-map nil)
 101
 102 (defvar ruler-mode)
 103 (defvar ruler-mode-ruler-function)
 104 (defvar hl-line-mode)
 105
 106 (defvar hexl-mode-old-hl-line-mode)
 107 (defvar hexl-mode-old-local-map)
 108 (defvar hexl-mode-old-mode-name)
 109 (defvar hexl-mode-old-major-mode)
 110 (defvar hexl-mode-old-ruler-mode)
 111 (defvar hexl-mode-old-isearch-search-fun-function)
 112 (defvar hexl-mode-old-require-final-newline)
 113 (defvar hexl-mode-old-syntax-table)
 114 (defvar hexl-mode-old-font-lock-keywords)
 115
 116 (defvar hexl-ascii-overlay nil
 117   "Overlay used to highlight ASCII element corresponding to current point.")
 118 (make-variable-buffer-local 'hexl-ascii-overlay)
 119
 120 (defvar hexl-font-lock-keywords
 121   '(("^\\([0-9a-f]+:\\).\\{40\\}  \\(.+$\\)"
 122      ;; "^\\([0-9a-f]+:\\).+  \\(.+$\\)"
 123      (1 'hexl-address-area t t)
 124      (2 'hexl-ascii-area t t)))
 125   "Font lock keywords used in `hexl-mode'.")
 126
 127 ;; routines
 128
 129 (put 'hexl-mode 'mode-class 'special)
 130
 131 ;;;###autoload
 132 (defun hexl-mode (&optional arg)
 133   "\\<hexl-mode-map>A mode for editing binary files in hex dump format.
 134 This is not an ordinary major mode; it alters some aspects
 135 of the current mode's behavior, but not all; also, you can exit
 136 Hexl mode and return to the previous mode using `hexl-mode-exit'.
 137
 138 This function automatically converts a buffer into the hexl format
 139 using the function `hexlify-buffer'.
 140
 141 Each line in the buffer has an \"address\" (displayed in hexadecimal)
 142 representing the offset into the file that the characters on this line
 143 are at and 16 characters from the file (displayed as hexadecimal
 144 values grouped every 16 bits) and as their ASCII values.
 145
 146 If any of the characters (displayed as ASCII characters) are
 147 unprintable (control or meta characters) they will be replaced as
 148 periods.
 149
 150 If `hexl-mode' is invoked with an argument the buffer is assumed to be
 151 in hexl format.
 152
 153 A sample format:
 154
 155   HEX ADDR: 0001 0203 0405 0607 0809 0a0b 0c0d 0e0f     ASCII-TEXT
 156   --------  ---- ---- ---- ---- ---- ---- ---- ----  ----------------
 157   00000000: 5468 6973 2069 7320 6865 786c 2d6d 6f64  This is hexl-mod
 158   00000010: 652e 2020 4561 6368 206c 696e 6520 7265  e.  Each line re
 159   00000020: 7072 6573 656e 7473 2031 3620 6279 7465  presents 16 byte
 160   00000030: 7320 6173 2068 6578 6164 6563 696d 616c  s as hexadecimal
 161   00000040: 2041 5343 4949 0a61 6e64 2070 7269 6e74   ASCII.and print
 162   00000050: 6162 6c65 2041 5343 4949 2063 6861 7261  able ASCII chara
 163   00000060: 6374 6572 732e 2020 416e 7920 636f 6e74  cters.  Any cont
 164   00000070: 726f 6c20 6f72 206e 6f6e 2d41 5343 4949  rol or non-ASCII
 165   00000080: 2063 6861 7261 6374 6572 730a 6172 6520   characters.are
 166   00000090: 6469 7370 6c61 7965 6420 6173 2070 6572  displayed as per
 167   000000a0: 696f 6473 2069 6e20 7468 6520 7072 696e  iods in the prin
 168   000000b0: 7461 626c 6520 6368 6172 6163 7465 7220  table character
 169   000000c0: 7265 6769 6f6e 2e0a                      region..
 170
 171 Movement is as simple as movement in a normal emacs text buffer.  Most
 172 cursor movement bindings are the same (ie. Use \\[hexl-backward-char], \\[hexl-forward-char], \\[hexl-next-line], and \\[hexl-previous-line]
 173 to move the cursor left, right, down, and up).
 174
 175 Advanced cursor movement commands (ala \\[hexl-beginning-of-line], \\[hexl-end-of-line], \\[hexl-beginning-of-buffer], and \\[hexl-end-of-buffer]) are
 176 also supported.
 177
 178 There are several ways to change text in hexl mode:
 179
 180 ASCII characters (character between space (0x20) and tilde (0x7E)) are
 181 bound to self-insert so you can simply type the character and it will
 182 insert itself (actually overstrike) into the buffer.
 183
 184 \\[hexl-quoted-insert] followed by another keystroke allows you to insert the key even if
 185 it isn't bound to self-insert.  An octal number can be supplied in place
 186 of another key to insert the octal number's ASCII representation.
 187
 188 \\[hexl-insert-hex-char] will insert a given hexadecimal value (if it is between 0 and 0xFF)
 189 into the buffer at the current point.
 190
 191 \\[hexl-insert-octal-char] will insert a given octal value (if it is between 0 and 0377)
 192 into the buffer at the current point.
 193
 194 \\[hexl-insert-decimal-char] will insert a given decimal value (if it is between 0 and 255)
 195 into the buffer at the current point.
 196
 197 \\[hexl-mode-exit] will exit hexl-mode.
 198
 199 Note: saving the file with any of the usual Emacs commands
 200 will actually convert it back to binary format while saving.
 201
 202 You can use \\[hexl-find-file] to visit a file in Hexl mode.
 203
 204 \\[describe-bindings] for advanced commands."
 205   (interactive "p")
 206   (unless (eq major-mode 'hexl-mode)
 207     (let ((modified (buffer-modified-p))
 208           (inhibit-read-only t)
 209           (original-point (- (point) (point-min)))
 210           max-address)
 211       (and (eobp) (not (bobp))
 212            (setq original-point (1- original-point)))
 213       (if (not (or (eq arg 1) (not arg)))
 214           ;; if no argument then we guess at hexl-max-address
 215           (setq max-address (+ (* (/ (1- (buffer-size)) 68) 16) 15))
 216         (setq max-address (1- (buffer-size)))
 217         ;; If the buffer's EOL type is -dos, we need to account for
 218         ;; extra CR characters added when hexlify-buffer writes the
 219         ;; buffer to a file.
 220         (when (eq (coding-system-eol-type buffer-file-coding-system) 1)
 221           (setq max-address (+ (count-lines (point-min) (point-max))
 222                                max-address))
 223           ;; But if there's no newline at the last line, we are off by
 224           ;; one; adjust.
 225           (or (eq (char-before (point-max)) ?\n)
 226               (setq max-address (1- max-address)))
 227           (setq original-point (+ (count-lines (point-min) (point))
 228                                   original-point))
 229           (or (bolp) (setq original-point (1- original-point))))
 230         (hexlify-buffer)
 231         (set-buffer-modified-p modified))
 232       (make-local-variable 'hexl-max-address)
 233       (setq hexl-max-address max-address)
 234       (condition-case nil
 235           (hexl-goto-address original-point)
 236         (error nil)))
 237
 238     ;; We do not turn off the old major mode; instead we just
 239     ;; override most of it.  That way, we can restore it perfectly.
 240     (make-local-variable 'hexl-mode-old-local-map)
 241     (setq hexl-mode-old-local-map (current-local-map))
 242     (use-local-map hexl-mode-map)
 243
 244     (make-local-variable 'hexl-mode-old-mode-name)
 245     (setq hexl-mode-old-mode-name mode-name)
 246     (setq mode-name "Hexl")
 247
 248     (set (make-local-variable 'hexl-mode-old-isearch-search-fun-function)
 249          isearch-search-fun-function)
 250     (set (make-local-variable 'isearch-search-fun-function)
 251          'hexl-isearch-search-function)
 252
 253     (make-local-variable 'hexl-mode-old-major-mode)
 254     (setq hexl-mode-old-major-mode major-mode)
 255     (setq major-mode 'hexl-mode)
 256
 257     (make-local-variable 'hexl-mode-old-ruler-mode)
 258     (setq hexl-mode-old-ruler-mode
 259           (and (boundp 'ruler-mode) ruler-mode))
 260
 261     (make-local-variable 'hexl-mode-old-hl-line-mode)
 262     (setq hexl-mode-old-hl-line-mode
 263           (and (boundp 'hl-line-mode) hl-line-mode))
 264
 265     (make-local-variable 'hexl-mode-old-syntax-table)
 266     (setq hexl-mode-old-syntax-table (syntax-table))
 267     (set-syntax-table (standard-syntax-table))
 268
 269     (add-hook 'write-contents-functions 'hexl-save-buffer nil t)
 270
 271     (make-local-variable 'hexl-mode-old-require-final-newline)
 272     (setq hexl-mode-old-require-final-newline require-final-newline)
 273     (make-local-variable 'require-final-newline)
 274     (setq require-final-newline nil)
 275
 276     (make-local-variable 'hexl-mode-old-font-lock-keywords)
 277     (setq hexl-mode-old-font-lock-keywords font-lock-defaults)
 278     (make-local-variable 'font-lock-defaults)
 279     (setq font-lock-defaults '(hexl-font-lock-keywords t))
 280
 281     ;; Add hooks to rehexlify or dehexlify on various events.
 282     (add-hook 'after-revert-hook 'hexl-after-revert-hook nil t)
 283
 284     (add-hook 'change-major-mode-hook 'hexl-maybe-dehexlify-buffer nil t)
 285
 286     ;; Set a callback function for eldoc.
 287     (set (make-local-variable 'eldoc-documentation-function)
 288          'hexl-print-current-point-info)
 289     (eldoc-add-command-completions "hexl-")
 290     (eldoc-remove-command "hexl-save-buffer"
 291                           "hexl-current-address")
 292
 293     (if hexl-follow-ascii (hexl-follow-ascii 1)))
 294   (run-mode-hooks 'hexl-mode-hook))
 295
 296
 297 (defun hexl-isearch-search-function ()
 298   (if (and (not isearch-regexp) (not isearch-word))
 299       (lambda (string &optional bound noerror count)
 300         (funcall
 301          (if isearch-forward 're-search-forward 're-search-backward)
 302          (if (> (length string) 80)
 303              (regexp-quote string)
 304            (mapconcat 'string string "\\(?:\n\\(?:[:a-f0-9]+ \\)+ \\)?"))
 305          bound noerror count))
 306     (let ((isearch-search-fun-function nil))
 307       (isearch-search-fun))))
 308
 309 (defun hexl-after-revert-hook ()
 310   (setq hexl-max-address (1- (buffer-size)))
 311   (hexlify-buffer)
 312   (set-buffer-modified-p nil))
 313
 314 (defvar hexl-in-save-buffer nil)
 315
 316 (defun hexl-save-buffer ()
 317   "Save a hexl format buffer as binary in visited file if modified."
 318   (interactive)
 319   (if hexl-in-save-buffer nil
 320     (set-buffer-modified-p (if (buffer-modified-p)
 321                                (save-excursion
 322                                  (let ((buf (generate-new-buffer " hexl"))
 323                                        (name (buffer-name))
 324                                        (file-name (buffer-file-name))
 325                                        (start (point-min))
 326                                        (end (point-max))
 327                                        modified)
 328                                    (set-buffer buf)
 329                                    (insert-buffer-substring name start end)
 330                                    (set-buffer name)
 331                                    (dehexlify-buffer)
 332                                    ;; Prevent infinite recursion.
 333                                    (let ((hexl-in-save-buffer t))
 334                                      (save-buffer))
 335                                    (setq modified (buffer-modified-p))
 336                                    (delete-region (point-min) (point-max))
 337                                    (insert-buffer-substring buf start end)
 338                                    (kill-buffer buf)
 339                                    modified))
 340                              (message "(No changes need to be saved)")
 341                              nil))
 342     ;; Return t to indicate we have saved t
 343     t))
 344
 345 ;;;###autoload
 346 (defun hexl-find-file (filename)
 347   "Edit file FILENAME in hexl-mode.
 348 Switch to a buffer visiting file FILENAME, creating one in none exists."
 349   (interactive
 350    (list
 351     (let ((completion-ignored-extensions nil))
 352       (read-file-name "Filename: " nil nil 'ret-must-match))))
 353   ;; Ignore the user's setting of default-major-mode.
 354   (let ((default-major-mode 'fundamental-mode))
 355     (find-file-literally filename))
 356   (if (not (eq major-mode 'hexl-mode))
 357       (hexl-mode)))
 358
 359 (defun hexl-mode-exit (&optional arg)
 360   "Exit Hexl mode, returning to previous mode.
 361 With arg, don't unhexlify buffer."
 362   (interactive "p")
 363   (if (or (eq arg 1) (not arg))
 364       (let ((modified (buffer-modified-p))
 365             (inhibit-read-only t)
 366             (original-point (1+ (hexl-current-address))))
 367         (dehexlify-buffer)
 368         (remove-hook 'write-contents-functions 'hexl-save-buffer t)
 369         (set-buffer-modified-p modified)
 370         (goto-char original-point)
 371         ;; Maybe adjust point for the removed CR characters.
 372         (when (eq (coding-system-eol-type buffer-file-coding-system) 1)
 373           (setq original-point (- original-point
 374                                   (count-lines (point-min) (point))))
 375           (or (bobp) (setq original-point (1+ original-point))))
 376         (goto-char original-point)))
 377
 378   (remove-hook 'after-revert-hook 'hexl-after-revert-hook t)
 379   (remove-hook 'change-major-mode-hook 'hexl-maybe-dehexlify-buffer t)
 380   (remove-hook 'post-command-hook 'hexl-follow-ascii-find t)
 381   (setq hexl-ascii-overlay nil)
 382
 383   (if (and (boundp 'ruler-mode) ruler-mode (not hexl-mode-old-ruler-mode))
 384       (ruler-mode 0))
 385   (if (and (boundp 'hl-line-mode) hl-line-mode (not hexl-mode-old-hl-line-mode))
 386       (hl-line-mode 0))
 387   (setq require-final-newline hexl-mode-old-require-final-newline)
 388   (setq mode-name hexl-mode-old-mode-name)
 389   (setq isearch-search-fun-function hexl-mode-old-isearch-search-fun-function)
 390   (use-local-map hexl-mode-old-local-map)
 391   (set-syntax-table hexl-mode-old-syntax-table)
 392   (setq font-lock-defaults hexl-mode-old-font-lock-keywords)
 393   (setq major-mode hexl-mode-old-major-mode)
 394   (force-mode-line-update))
 395
 396 (defun hexl-maybe-dehexlify-buffer ()
 397   "Convert a hexl format buffer to binary.
 398 Ask the user for confirmation."
 399   (if (y-or-n-p "Convert contents back to binary format? ")
 400       (let ((modified (buffer-modified-p))
 401             (inhibit-read-only t)
 402             (original-point (1+ (hexl-current-address))))
 403         (dehexlify-buffer)
 404         (remove-hook 'write-contents-functions 'hexl-save-buffer t)
 405         (set-buffer-modified-p modified)
 406         (goto-char original-point))))
 407
 408 (defun hexl-current-address (&optional validate)
 409   "Return current hexl-address."
 410   (interactive)
 411   (let ((current-column (- (% (- (point) (point-min) -1) 68) 11))
 412         (hexl-address 0))
 413     (if (< current-column 0)
 414         (if validate
 415             (error "Point is not on a character in the file")
 416           (setq current-column 0)))
 417     (setq hexl-address
 418           (+ (* (/ (- (point) (point-min) -1) 68) 16)
 419              (if (>= current-column 41)
 420                  (- current-column 41)
 421                (/ (- current-column  (/ current-column 5)) 2))))
 422     (when (interactive-p)
 423       (message "Current address is %d/0x%08x" hexl-address hexl-address))
 424     hexl-address))
 425
 426 (defun hexl-print-current-point-info ()
 427   "Return current hexl-address in string.
 428 This function is indented to be used as eldoc callback."
 429   (let ((addr (hexl-current-address)))
 430     (format "Current address is %d/0x%08x" addr addr)))
 431
 432 (defun hexl-address-to-marker (address)
 433   "Return buffer position for ADDRESS."
 434   (interactive "nAddress: ")
 435   (+ (* (/ address 16) 68) 10 (point-min) (/ (* (% address 16) 5) 2)))
 436
 437 (defun hexl-goto-address (address)
 438   "Goto hexl-mode (decimal) address ADDRESS.
 439 Signal error if ADDRESS out of range."
 440   (interactive "nAddress: ")
 441   (if (or (< address 0) (> address hexl-max-address))
 442       (error "Out of hexl region"))
 443   (goto-char (hexl-address-to-marker address)))
 444
 445 (defun hexl-goto-hex-address (hex-address)
 446   "Go to hexl-mode address (hex string) HEX-ADDRESS.
 447 Signal error if HEX-ADDRESS is out of range."
 448   (interactive "sHex Address: ")
 449   (hexl-goto-address (hexl-hex-string-to-integer hex-address)))
 450
 451 (defun hexl-hex-string-to-integer (hex-string)
 452   "Return decimal integer for HEX-STRING."
 453   (interactive "sHex number: ")
 454   (let ((hex-num 0))
 455     (while (not (equal hex-string ""))
 456       (setq hex-num (+ (* hex-num 16)
 457                        (hexl-hex-char-to-integer (string-to-char hex-string))))
 458       (setq hex-string (substring hex-string 1)))
 459     hex-num))
 460
 461 (defun hexl-octal-string-to-integer (octal-string)
 462   "Return decimal integer for OCTAL-STRING."
 463   (interactive "sOctal number: ")
 464   (let ((oct-num 0))
 465     (while (not (equal octal-string ""))
 466       (setq oct-num (+ (* oct-num 8)
 467                        (hexl-oct-char-to-integer
 468                         (string-to-char octal-string))))
 469       (setq octal-string (substring octal-string 1)))
 470     oct-num))
 471
 472 ;; move point functions
 473
 474 (defun hexl-backward-char (arg)
 475   "Move to left ARG bytes (right if ARG negative) in hexl-mode."
 476   (interactive "p")
 477   (hexl-goto-address (- (hexl-current-address) arg)))
 478
 479 (defun hexl-forward-char (arg)
 480   "Move right ARG bytes (left if ARG negative) in hexl-mode."
 481   (interactive "p")
 482   (hexl-goto-address (+ (hexl-current-address) arg)))
 483
 484 (defun hexl-backward-short (arg)
 485   "Move to left ARG shorts (right if ARG negative) in hexl-mode."
 486   (interactive "p")
 487   (hexl-goto-address (let ((address (hexl-current-address)))
 488                        (if (< arg 0)
 489                            (progn
 490                              (setq arg (- arg))
 491                              (while (> arg 0)
 492                                (if (not (equal address (logior address 3)))
 493                                    (if (> address hexl-max-address)
 494                                        (progn
 495                                          (message "End of buffer.")
 496                                          (setq address hexl-max-address))
 497                                      (setq address (logior address 3)))
 498                                  (if (> address hexl-max-address)
 499                                      (progn
 500                                        (message "End of buffer.")
 501                                        (setq address hexl-max-address))
 502                                    (setq address (+ address 4))))
 503                                (setq arg (1- arg)))
 504                              (if (> address hexl-max-address)
 505                                  (progn
 506                                    (message "End of buffer.")
 507                                    (setq address hexl-max-address))
 508                                (setq address (logior address 3))))
 509                          (while (> arg 0)
 510                            (if (not (equal address (logand address -4)))
 511                                (setq address (logand address -4))
 512                              (if (not (equal address 0))
 513                                  (setq address (- address 4))
 514                                (message "Beginning of buffer.")))
 515                            (setq arg (1- arg))))
 516                        address)))
 517
 518 (defun hexl-forward-short (arg)
 519   "Move right ARG shorts (left if ARG negative) in hexl-mode."
 520   (interactive "p")
 521   (hexl-backward-short (- arg)))
 522
 523 (defun hexl-backward-word (arg)
 524   "Move to left ARG words (right if ARG negative) in hexl-mode."
 525   (interactive "p")
 526   (hexl-goto-address (let ((address (hexl-current-address)))
 527                        (if (< arg 0)
 528                            (progn
 529                              (setq arg (- arg))
 530                              (while (> arg 0)
 531                                (if (not (equal address (logior address 7)))
 532                                    (if (> address hexl-max-address)
 533                                        (progn
 534                                          (message "End of buffer.")
 535                                          (setq address hexl-max-address))
 536                                      (setq address (logior address 7)))
 537                                  (if (> address hexl-max-address)
 538                                      (progn
 539                                        (message "End of buffer.")
 540                                        (setq address hexl-max-address))
 541                                    (setq address (+ address 8))))
 542                                (setq arg (1- arg)))
 543                              (if (> address hexl-max-address)
 544                                  (progn
 545                                    (message "End of buffer.")
 546                                    (setq address hexl-max-address))
 547                                (setq address (logior address 7))))
 548                          (while (> arg 0)
 549                            (if (not (equal address (logand address -8)))
 550                                (setq address (logand address -8))
 551                              (if (not (equal address 0))
 552                                  (setq address (- address 8))
 553                                (message "Beginning of buffer.")))
 554                            (setq arg (1- arg))))
 555                        address)))
 556
 557 (defun hexl-forward-word (arg)
 558   "Move right ARG words (left if ARG negative) in hexl-mode."
 559   (interactive "p")
 560   (hexl-backward-word (- arg)))
 561
 562 (defun hexl-previous-line (arg)
 563   "Move vertically up ARG lines [16 bytes] (down if ARG negative) in hexl-mode.
 564 If there is byte at the target address move to the last byte in that line."
 565   (interactive "p")
 566   (hexl-next-line (- arg)))
 567
 568 (defun hexl-next-line (arg)
 569   "Move vertically down ARG lines [16 bytes] (up if ARG negative) in hexl-mode.
 570 If there is no byte at the target address move to the last byte in that line."
 571   (interactive "p")
 572   (hexl-goto-address (let ((address (+ (hexl-current-address) (* arg 16))))
 573                        (if (and (< arg 0) (< address 0))
 574                                 (progn (message "Out of hexl region.")
 575                                        (setq address
 576                                              (% (hexl-current-address) 16)))
 577                          (if (and (> address hexl-max-address)
 578                                   (< (% hexl-max-address 16) (% address 16)))
 579                              (setq address hexl-max-address)
 580                            (if (> address hexl-max-address)
 581                                (progn (message "Out of hexl region.")
 582                                       (setq
 583                                        address
 584                                        (+ (logand hexl-max-address -16)
 585                                           (% (hexl-current-address) 16)))))))
 586                        address)))
 587
 588 (defun hexl-beginning-of-buffer (arg)
 589   "Move to the beginning of the hexl buffer.
 590 Leaves `hexl-mark' at previous position.
 591 With prefix arg N, puts point N bytes of the way from the true beginning."
 592   (interactive "p")
 593   (push-mark (point))
 594   (hexl-goto-address (+ 0 (1- arg))))
 595
 596 (defun hexl-end-of-buffer (arg)
 597   "Go to `hexl-max-address' minus ARG."
 598   (interactive "p")
 599   (push-mark (point))
 600   (hexl-goto-address (- hexl-max-address (1- arg))))
 601
 602 (defun hexl-beginning-of-line ()
 603   "Goto beginning of line in hexl mode."
 604   (interactive)
 605   (goto-char (+ (* (/ (point) 68) 68) 11)))
 606
 607 (defun hexl-end-of-line ()
 608   "Goto end of line in hexl mode."
 609   (interactive)
 610   (hexl-goto-address (let ((address (logior (hexl-current-address) 15)))
 611                        (if (> address hexl-max-address)
 612                            (setq address hexl-max-address))
 613                        address)))
 614
 615 (defun hexl-scroll-down (arg)
 616   "Scroll hexl buffer window upward ARG lines; or near full window if no ARG."
 617   (interactive "P")
 618   (if (null arg)
 619       (setq arg (1- (window-height)))
 620     (setq arg (prefix-numeric-value arg)))
 621   (hexl-scroll-up (- arg)))
 622
 623 (defun hexl-scroll-up (arg)
 624   "Scroll hexl buffer window upward ARG lines; or near full window if no ARG.
 625 If there's no byte at the target address, move to the first or last line."
 626   (interactive "P")
 627   (if (null arg)
 628       (setq arg (1- (window-height)))
 629     (setq arg (prefix-numeric-value arg)))
 630   (let* ((movement (* arg 16))
 631          (address (hexl-current-address))
 632          (dest (+ address movement)))
 633     (cond
 634      ;; If possible, try to stay at the same offset from the beginning
 635      ;; of the 16-byte group, even if we move to the first or last
 636      ;; group.
 637      ((and (> dest hexl-max-address)
 638            (>= (% hexl-max-address 16) (% address 16)))
 639       (setq dest (+ (logand hexl-max-address -16) (% address 16))))
 640      ((> dest hexl-max-address)
 641       (setq dest hexl-max-address))
 642      ((< dest 0)
 643       (setq dest (% address 16))))
 644     (if (/= dest (+ address movement))
 645         (message "Out of hexl region."))
 646     (hexl-goto-address dest)
 647     (recenter 0)))
 648
 649 (defun hexl-beginning-of-1k-page ()
 650   "Go to beginning of 1k boundary."
 651   (interactive)
 652   (hexl-goto-address (logand (hexl-current-address) -1024)))
 653
 654 (defun hexl-end-of-1k-page ()
 655   "Go to end of 1k boundary."
 656   (interactive)
 657   (hexl-goto-address (let ((address (logior (hexl-current-address) 1023)))
 658                        (if (> address hexl-max-address)
 659                            (setq address hexl-max-address))
 660                        address)))
 661
 662 (defun hexl-beginning-of-512b-page ()
 663   "Go to beginning of 512 byte boundary."
 664   (interactive)
 665   (hexl-goto-address (logand (hexl-current-address) -512)))
 666
 667 (defun hexl-end-of-512b-page ()
 668   "Go to end of 512 byte boundary."
 669   (interactive)
 670   (hexl-goto-address (let ((address (logior (hexl-current-address) 511)))
 671                        (if (> address hexl-max-address)
 672                            (setq address hexl-max-address))
 673                        address)))
 674
 675 (defun hexl-quoted-insert (arg)
 676   "Read next input character and insert it.
 677 Useful for inserting control characters and non-ASCII characters given their
 678 numerical code.
 679 You may also type octal digits, to insert a character with that code."
 680   (interactive "p")
 681   (hexl-insert-multibyte-char (read-quoted-char) arg))
 682
 683 ;00000000: 0011 2233 4455 6677 8899 aabb ccdd eeff  0123456789ABCDEF
 684
 685 ;;;###autoload
 686 (defun hexlify-buffer ()
 687   "Convert a binary buffer to hexl format.
 688 This discards the buffer's undo information."
 689   (interactive)
 690   (and buffer-undo-list
 691        (or (y-or-n-p "Converting to hexl format discards undo info; ok? ")
 692            (error "Aborted")))
 693   (setq buffer-undo-list nil)
 694   ;; Don't decode text in the ASCII part of `hexl' program output.
 695   (let ((coding-system-for-read 'raw-text)
 696         (coding-system-for-write buffer-file-coding-system)
 697         (buffer-undo-list t))
 698     (apply 'call-process-region (point-min) (point-max)
 699            (expand-file-name hexl-program exec-directory)
 700            t t nil (split-string hexl-options))
 701     (if (> (point) (hexl-address-to-marker hexl-max-address))
 702         (hexl-goto-address hexl-max-address))))
 703
 704 (defun dehexlify-buffer ()
 705   "Convert a hexl format buffer to binary.
 706 This discards the buffer's undo information."
 707   (interactive)
 708   (and buffer-undo-list
 709        (or (y-or-n-p "Converting from hexl format discards undo info; ok? ")
 710            (error "Aborted")))
 711   (setq buffer-undo-list nil)
 712   (let ((coding-system-for-write 'raw-text)
 713         (coding-system-for-read buffer-file-coding-system)
 714         (buffer-undo-list t))
 715     (apply 'call-process-region (point-min) (point-max)
 716            (expand-file-name hexl-program exec-directory)
 717            t t nil "-de" (split-string hexl-options))))
 718
 719 (defun hexl-char-after-point ()
 720   "Return char for ASCII hex digits at point."
 721   (hexl-htoi (char-after (point))
 722              (char-after (1+ (point)))))
 723
 724 (defun hexl-htoi (lh rh)
 725   "Hex (char) LH (char) RH to integer."
 726     (+ (* (hexl-hex-char-to-integer lh) 16)
 727        (hexl-hex-char-to-integer rh)))
 728
 729 (defun hexl-hex-char-to-integer (character)
 730   "Take a char and return its value as if it was a hex digit."
 731   (if (and (>= character ?0) (<= character ?9))
 732       (- character ?0)
 733     (let ((ch (logior character 32)))
 734       (if (and (>= ch ?a) (<= ch ?f))
 735           (- ch (- ?a 10))
 736         (error "Invalid hex digit `%c'" ch)))))
 737
 738 (defun hexl-oct-char-to-integer (character)
 739   "Take a char and return its value as if it was a octal digit."
 740   (if (and (>= character ?0) (<= character ?7))
 741       (- character ?0)
 742     (error "Invalid octal digit `%c'" character)))
 743
 744 (defun hexl-printable-character (ch)
 745   "Return a displayable string for character CH."
 746   (format "%c" (if hexl-iso
 747                    (if (or (< ch 32) (and (>= ch 127) (< ch 160)))
 748                        46
 749                      ch)
 750                  (if (or (< ch 32) (>= ch 127))
 751                      46
 752                    ch))))
 753
 754 (defun hexl-insert-multibyte-char (ch num)
 755   "Insert a possibly multibyte character CH NUM times.
 756
 757 Non-ASCII characters are first encoded with `buffer-file-coding-system',
 758 and their encoded form is inserted byte by byte."
 759   (let ((charset (char-charset ch))
 760         (coding (if (or (null buffer-file-coding-system)
 761                         ;; coding-system-type equals t means undecided.
 762                         (eq (coding-system-type buffer-file-coding-system) t))
 763                     default-buffer-file-coding-system
 764                   buffer-file-coding-system)))
 765     (cond ((and (> ch 0) (< ch 256))
 766            (hexl-insert-char ch num))
 767           ((eq charset 'unknown)
 768            (error
 769             "0x%x -- invalid character code; use \\[hexl-insert-hex-string]"
 770             ch))
 771           (t
 772            (let ((encoded (encode-coding-char ch coding))
 773                  (internal (string-as-unibyte (char-to-string ch)))
 774                  internal-hex)
 775              ;; If encode-coding-char returns nil, it means our character
 776              ;; cannot be safely encoded with buffer-file-coding-system.
 777              ;; In that case, we offer to insert the internal representation
 778              ;; of that character, byte by byte.
 779              (when (null encoded)
 780                (setq internal-hex
 781                      (mapconcat (function (lambda (c) (format "%x" c)))
 782                                 internal " "))
 783                (if (yes-or-no-p
 784                     (format
 785                      "Insert char 0x%x's internal representation \"%s\"? "
 786                      ch internal-hex))
 787                    (setq encoded internal)
 788                  (error
 789                   "Can't encode `0x%x' with this buffer's coding system; try \\[hexl-insert-hex-string]"
 790                   ch)))
 791              (while (> num 0)
 792                (mapc
 793                 (function (lambda (c) (hexl-insert-char c 1))) encoded)
 794                (setq num (1- num))))))))
 795
 796 (defun hexl-self-insert-command (arg)
 797   "Insert this character.
 798 Interactively, with a numeric argument, insert this character that many times.
 799
 800 Non-ASCII characters are first encoded with `buffer-file-coding-system',
 801 and their encoded form is inserted byte by byte."
 802   (interactive "p")
 803   (hexl-insert-multibyte-char last-command-char arg))
 804
 805 (defun hexl-insert-char (ch num)
 806   "Insert the character CH NUM times in a hexl buffer.
 807
 808 CH must be a unibyte character whose value is between 0 and 255."
 809   (if (or (< ch 0) (> ch 255))
 810       (error "Invalid character 0x%x -- must be in the range [0..255]" ch))
 811   (let ((address (hexl-current-address t)))
 812     (while (> num 0)
 813       (let ((hex-position
 814              (+ (* (/ address 16) 68)
 815                 10 (point-min)
 816                 (* 2 (% address 16))
 817                 (/ (% address 16) 2)))
 818             (ascii-position
 819              (+ (* (/ address 16) 68) 51 (point-min) (% address 16)))
 820             at-ascii-position)
 821         (if (= (point) ascii-position)
 822             (setq at-ascii-position t))
 823         (goto-char hex-position)
 824         (delete-char 2)
 825         (insert (format "%02x" ch))
 826         (goto-char ascii-position)
 827         (delete-char 1)
 828         (insert (hexl-printable-character ch))
 829         (or (eq address hexl-max-address)
 830             (setq address (1+ address)))
 831         (hexl-goto-address address)
 832         (if at-ascii-position
 833             (progn
 834               (beginning-of-line)
 835               (forward-char 51)
 836               (forward-char (% address 16)))))
 837       (setq num (1- num)))))
 838
 839 ;; hex conversion
 840
 841 (defun hexl-insert-hex-char (arg)
 842   "Insert a character given by its hexadecimal code ARG times at point."
 843   (interactive "p")
 844   (let ((num (hexl-hex-string-to-integer (read-string "Hex number: "))))
 845     (if (< num 0)
 846         (error "Hex number out of range")
 847       (hexl-insert-multibyte-char num arg))))
 848
 849 (defun hexl-insert-hex-string (str arg)
 850   "Insert hexadecimal string STR at point ARG times.
 851 Embedded whitespace, dashes, and periods in the string are ignored."
 852   (interactive "sHex string: \np")
 853   (setq str (replace-regexp-in-string "[- \t.]" "" str))
 854   (let ((chars '()))
 855     (let ((len (length str))
 856           (idx 0))
 857       (if (eq (logand len 1) 1)
 858           (let ((num (hexl-hex-string-to-integer (substring str 0 1))))
 859             (setq chars (cons num chars))
 860             (setq idx 1)))
 861       (while (< idx len)
 862         (let* ((nidx (+ idx 2))
 863                (num (hexl-hex-string-to-integer (substring str idx nidx))))
 864           (setq chars (cons num chars))
 865           (setq idx nidx))))
 866     (setq chars (nreverse chars))
 867     (while (> arg 0)
 868       (let ((chars chars))
 869         (while chars
 870           (hexl-insert-char (car chars) 1)
 871           (setq chars (cdr chars))))
 872       (setq arg (- arg 1)))))
 873
 874 (defun hexl-insert-decimal-char (arg)
 875   "Insert a character given by its decimal code ARG times at point."
 876   (interactive "p")
 877   (let ((num (string-to-number (read-string "Decimal Number: "))))
 878     (if (< num 0)
 879         (error "Decimal number out of range")
 880       (hexl-insert-multibyte-char num arg))))
 881
 882 (defun hexl-insert-octal-char (arg)
 883   "Insert a character given by its octal code ARG times at point."
 884   (interactive "p")
 885   (let ((num (hexl-octal-string-to-integer (read-string "Octal Number: "))))
 886     (if (< num 0)
 887         (error "Decimal number out of range")
 888       (hexl-insert-multibyte-char num arg))))
 889
 890 (defun hexl-follow-ascii (&optional arg)
 891   "Toggle following ASCII in Hexl buffers.
 892 With prefix ARG, turn on following if and only if ARG is positive.
 893 When following is enabled, the ASCII character corresponding to the
 894 element under the point is highlighted.
 895 Customize the variable `hexl-follow-ascii' to disable this feature."
 896   (interactive "P")
 897   (let ((on-p (if arg
 898                   (> (prefix-numeric-value arg) 0)
 899                (not hexl-ascii-overlay))))
 900
 901     (if on-p
 902       ;; turn it on
 903       (if (not hexl-ascii-overlay)
 904           (progn
 905             (setq hexl-ascii-overlay (make-overlay 1 1)
 906                   hexl-follow-ascii t)
 907             (overlay-put hexl-ascii-overlay 'face 'highlight)
 908             (add-hook 'post-command-hook 'hexl-follow-ascii-find nil t)))
 909       ;; turn it off
 910       (if hexl-ascii-overlay
 911           (progn
 912             (delete-overlay hexl-ascii-overlay)
 913             (setq hexl-ascii-overlay nil
 914                   hexl-follow-ascii nil)
 915             (remove-hook 'post-command-hook 'hexl-follow-ascii-find t)
 916             )))))
 917
 918 (defun hexl-activate-ruler ()
 919   "Activate `ruler-mode'"
 920   (require 'ruler-mode)
 921   (set (make-local-variable 'ruler-mode-ruler-function)
 922        'hexl-mode-ruler)
 923   (ruler-mode 1))
 924
 925 (defun hexl-follow-line ()
 926   "Activate `hl-line-mode'"
 927   (require 'frame)
 928   (require 'hl-line)
 929   (with-no-warnings
 930     (set (make-local-variable 'hl-line-range-function)
 931          'hexl-highlight-line-range)
 932     (set (make-local-variable 'hl-line-face)
 933          'highlight))
 934   (hl-line-mode 1))
 935
 936 (defun hexl-highlight-line-range ()
 937   "Return the range of address area for the point.
 938 This function is assumed to be used as call back function for `hl-line-mode'."
 939   (cons
 940    (line-beginning-position)
 941    ;; 9 stands for (length "87654321:")
 942    (+ (line-beginning-position) 9)))
 943
 944 (defun hexl-follow-ascii-find ()
 945   "Find and highlight the ASCII element corresponding to current point."
 946   (let ((pos (+ 51
 947                 (- (point) (current-column))
 948                 (mod (hexl-current-address) 16))))
 949     (move-overlay hexl-ascii-overlay pos (1+ pos))
 950     ))
 951
 952 (defun hexl-mode-ruler ()
 953   "Return a string ruler for hexl mode."
 954   (let* ((highlight (mod (hexl-current-address) 16))
 955          (s " 87654321  0011 2233 4455 6677 8899 aabb ccdd eeff  0123456789abcdef")
 956          (pos 0))
 957     (set-text-properties 0 (length s) nil s)
 958     ;; Turn spaces in the header into stretch specs so they work
 959     ;; regardless of the header-line face.
 960     (while (string-match "[ \t]+" s pos)
 961       (setq pos (match-end 0))
 962       (put-text-property (match-beginning 0) pos 'display
 963                          ;; Assume fixed-size chars
 964                          `(space :align-to ,(1- pos))
 965                          s))
 966     ;; Highlight the current column.
 967     (put-text-property (+ 11 (/ (* 5 highlight) 2))
 968                        (+ 13 (/ (* 5 highlight) 2))
 969                        'face 'highlight s)
 970     ;; Highlight the current ascii column
 971     (put-text-property (+ 13 39 highlight) (+ 13 40 highlight)
 972                        'face 'highlight s)
 973     s))
 974
 975 ;; startup stuff.
 976
 977 (if hexl-mode-map
 978     nil
 979   (setq hexl-mode-map (make-keymap))
 980   ;; Make all self-inserting keys go through hexl-self-insert-command,
 981   ;; because we need to convert them to unibyte characters before
 982   ;; inserting them into the buffer.
 983   (define-key hexl-mode-map [remap self-insert-command] 'hexl-self-insert-command)
 984
 985   (define-key hexl-mode-map "\C-m" 'hexl-self-insert-command)
 986   (define-key hexl-mode-map [left] 'hexl-backward-char)
 987   (define-key hexl-mode-map [right] 'hexl-forward-char)
 988   (define-key hexl-mode-map [up] 'hexl-previous-line)
 989   (define-key hexl-mode-map [down] 'hexl-next-line)
 990   (define-key hexl-mode-map [M-left] 'hexl-backward-short)
 991   (define-key hexl-mode-map [M-right] 'hexl-forward-short)
 992   (define-key hexl-mode-map [next] 'hexl-scroll-up)
 993   (define-key hexl-mode-map [prior] 'hexl-scroll-down)
 994   (define-key hexl-mode-map [home] 'hexl-beginning-of-line)
 995   (define-key hexl-mode-map [end] 'hexl-end-of-line)
 996   (define-key hexl-mode-map [C-home] 'hexl-beginning-of-buffer)
 997   (define-key hexl-mode-map [C-end] 'hexl-end-of-buffer)
 998   (define-key hexl-mode-map [deletechar] 'undefined)
 999   (define-key hexl-mode-map [deleteline] 'undefined)
1000   (define-key hexl-mode-map [insertline] 'undefined)
1001   (define-key hexl-mode-map [S-delete] 'undefined)
1002   (define-key hexl-mode-map "\177" 'undefined)
1003
1004   (define-key hexl-mode-map "\C-a" 'hexl-beginning-of-line)
1005   (define-key hexl-mode-map "\C-b" 'hexl-backward-char)
1006   (define-key hexl-mode-map "\C-d" 'undefined)
1007   (define-key hexl-mode-map "\C-e" 'hexl-end-of-line)
1008   (define-key hexl-mode-map "\C-f" 'hexl-forward-char)
1009
1010   (if (not (eq (key-binding (char-to-string help-char)) 'help-command))
1011       (define-key hexl-mode-map (char-to-string help-char) 'undefined))
1012
1013   (define-key hexl-mode-map "\C-k" 'undefined)
1014   (define-key hexl-mode-map "\C-n" 'hexl-next-line)
1015   (define-key hexl-mode-map "\C-o" 'undefined)
1016   (define-key hexl-mode-map "\C-p" 'hexl-previous-line)
1017   (define-key hexl-mode-map "\C-q" 'hexl-quoted-insert)
1018   (define-key hexl-mode-map "\C-t" 'undefined)
1019   (define-key hexl-mode-map "\C-v" 'hexl-scroll-up)
1020   (define-key hexl-mode-map "\C-w" 'undefined)
1021   (define-key hexl-mode-map "\C-y" 'undefined)
1022
1023   (fset 'hexl-ESC-prefix (copy-keymap 'ESC-prefix))
1024   (define-key hexl-mode-map "\e" 'hexl-ESC-prefix)
1025   (define-key hexl-mode-map "\e\C-a" 'hexl-beginning-of-512b-page)
1026   (define-key hexl-mode-map "\e\C-b" 'hexl-backward-short)
1027   (define-key hexl-mode-map "\e\C-d" 'hexl-insert-decimal-char)
1028   (define-key hexl-mode-map "\e\C-e" 'hexl-end-of-512b-page)
1029   (define-key hexl-mode-map "\e\C-f" 'hexl-forward-short)
1030   (define-key hexl-mode-map "\e\C-i" 'undefined)
1031   (define-key hexl-mode-map "\e\C-j" 'undefined)
1032   (define-key hexl-mode-map "\e\C-k" 'undefined)
1033   (define-key hexl-mode-map "\e\C-o" 'hexl-insert-octal-char)
1034   (define-key hexl-mode-map "\e\C-q" 'undefined)
1035   (define-key hexl-mode-map "\e\C-t" 'undefined)
1036   (define-key hexl-mode-map "\e\C-x" 'hexl-insert-hex-char)
1037   (define-key hexl-mode-map "\eb" 'hexl-backward-word)
1038   (define-key hexl-mode-map "\ec" 'undefined)
1039   (define-key hexl-mode-map "\ed" 'undefined)
1040   (define-key hexl-mode-map "\ef" 'hexl-forward-word)
1041   (define-key hexl-mode-map "\eg" 'hexl-goto-hex-address)
1042   (define-key hexl-mode-map "\ei" 'undefined)
1043   (define-key hexl-mode-map "\ej" 'hexl-goto-address)
1044   (define-key hexl-mode-map "\ek" 'undefined)
1045   (define-key hexl-mode-map "\el" 'undefined)
1046   (define-key hexl-mode-map "\eq" 'undefined)
1047   (define-key hexl-mode-map "\es" 'undefined)
1048   (define-key hexl-mode-map "\et" 'undefined)
1049   (define-key hexl-mode-map "\eu" 'undefined)
1050   (define-key hexl-mode-map "\ev" 'hexl-scroll-down)
1051   (define-key hexl-mode-map "\ey" 'undefined)
1052   (define-key hexl-mode-map "\ez" 'undefined)
1053   (define-key hexl-mode-map "\e<" 'hexl-beginning-of-buffer)
1054   (define-key hexl-mode-map "\e>" 'hexl-end-of-buffer)
1055
1056   (fset 'hexl-C-c-prefix (copy-keymap mode-specific-map))
1057   (define-key hexl-mode-map "\C-c" 'hexl-C-c-prefix)
1058   (define-key hexl-mode-map "\C-c\C-c" 'hexl-mode-exit)
1059
1060   (fset 'hexl-C-x-prefix (copy-keymap 'Control-X-prefix))
1061   (define-key hexl-mode-map "\C-x" 'hexl-C-x-prefix)
1062   (define-key hexl-mode-map "\C-x[" 'hexl-beginning-of-1k-page)
1063   (define-key hexl-mode-map "\C-x]" 'hexl-end-of-1k-page)
1064   (define-key hexl-mode-map "\C-x\C-p" 'undefined)
1065   (define-key hexl-mode-map "\C-x\C-s" 'hexl-save-buffer)
1066   (define-key hexl-mode-map "\C-x\C-t" 'undefined))
1067
1068 (provide 'hexl)
1069
1070 ;;; arch-tag: d5a7aa8a-9bce-480b-bcff-6c4c7ca5ea4a
1071 ;;; hexl.el ends here