lisp/hexl.el

   1 ;;; hexl.el --- edit a file in a hex dump format using the hexl filter.
   2
   3 ;; Copyright (C) 1989, 1994 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
  23 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  24
  25 ;;; Commentary:
  26
  27 ;; This package implements a major mode for editing binary files.  It uses
  28 ;; a program called hexl, supplied with the GNU Emacs distribution, that
  29 ;; can filter a binary into an editable format or from the format back into
  30 ;; binary.  For full instructions, invoke `hexl-mode' on an empty buffer and
  31 ;; do `M-x describe-mode'.
  32 ;;
  33 ;; This may be useful in your .emacs:
  34 ;;
  35 ;;      (autoload 'hexl-find-file "hexl"
  36 ;;        "Edit file FILENAME in hexl-mode." t)
  37 ;;
  38 ;;      (define-key global-map "\C-c\C-h" 'hexl-find-file)
  39 ;;
  40 ;; NOTE: Remember to change HEXL-PROGRAM or HEXL-OPTIONS if needed.
  41 ;;
  42 ;; Currently hexl only supports big endian hex output with 16 bit
  43 ;; grouping.
  44 ;;
  45 ;; -iso in `hexl-options' will allow iso characters to display in the
  46 ;; ASCII region of the screen (if your emacs supports this) instead of
  47 ;; changing them to dots.
  48
  49 ;;; Code:
  50
  51 ;;
  52 ;; vars here
  53 ;;
  54
  55 (defvar hexl-program "hexl"
  56   "The program that will hexlify and dehexlify its stdin.
  57 `hexl-program' will always be concatenated with `hexl-options'
  58 and \"-de\" when dehexlifying a buffer.")
  59
  60 (defvar hexl-iso ""
  61   "If your emacs can handle ISO characters, this should be set to
  62 \"-iso\" otherwise it should be \"\".")
  63
  64 (defvar hexl-options (format "-hex %s" hexl-iso)
  65   "Options to hexl-program that suit your needs.")
  66
  67 (defvar hexlify-command
  68   (format "%s%s %s" exec-directory hexl-program hexl-options)
  69   "The command to use to hexlify a buffer.")
  70
  71 (defvar dehexlify-command
  72   (format "%s%s -de %s" exec-directory hexl-program hexl-options)
  73   "The command to use to unhexlify a buffer.")
  74
  75 (defvar hexl-max-address 0
  76   "Maximum offset into hexl buffer.")
  77
  78 (defvar hexl-mode-map nil)
  79
  80 (defvar hexl-mode-old-local-map)
  81 (defvar hexl-mode-old-mode-name)
  82 (defvar hexl-mode-old-major-mode)
  83 (defvar hexl-mode-old-write-contents-hooks)
  84 (defvar hexl-mode-old-require-final-newline)
  85 (defvar hexl-mode-old-syntax-table)
  86
  87 ;; routines
  88
  89 ;;;###autoload
  90 (defun hexl-mode (&optional arg)
  91   "\\<hexl-mode-map>
  92 A major mode for editing binary files in hex dump format.
  93
  94 This function automatically converts a buffer into the hexl format
  95 using the function `hexlify-buffer'.
  96
  97 Each line in the buffer has an \"address\" (displayed in hexadecimal)
  98 representing the offset into the file that the characters on this line
  99 are at and 16 characters from the file (displayed as hexadecimal
 100 values grouped every 16 bits) and as their ASCII values.
 101
 102 If any of the characters (displayed as ASCII characters) are
 103 unprintable (control or meta characters) they will be replaced as
 104 periods.
 105
 106 If `hexl-mode' is invoked with an argument the buffer is assumed to be
 107 in hexl format.
 108
 109 A sample format:
 110
 111   HEX ADDR: 0001 0203 0405 0607 0809 0a0b 0c0d 0e0f     ASCII-TEXT
 112   --------  ---- ---- ---- ---- ---- ---- ---- ----  ----------------
 113   00000000: 5468 6973 2069 7320 6865 786c 2d6d 6f64  This is hexl-mod
 114   00000010: 652e 2020 4561 6368 206c 696e 6520 7265  e.  Each line re
 115   00000020: 7072 6573 656e 7473 2031 3620 6279 7465  presents 16 byte
 116   00000030: 7320 6173 2068 6578 6164 6563 696d 616c  s as hexadecimal
 117   00000040: 2041 5343 4949 0a61 6e64 2070 7269 6e74   ASCII.and print
 118   00000050: 6162 6c65 2041 5343 4949 2063 6861 7261  able ASCII chara
 119   00000060: 6374 6572 732e 2020 416e 7920 636f 6e74  cters.  Any cont
 120   00000070: 726f 6c20 6f72 206e 6f6e 2d41 5343 4949  rol or non-ASCII
 121   00000080: 2063 6861 7261 6374 6572 730a 6172 6520   characters.are
 122   00000090: 6469 7370 6c61 7965 6420 6173 2070 6572  displayed as per
 123   000000a0: 696f 6473 2069 6e20 7468 6520 7072 696e  iods in the prin
 124   000000b0: 7461 626c 6520 6368 6172 6163 7465 7220  table character
 125   000000c0: 7265 6769 6f6e 2e0a                      region..
 126
 127 Movement is as simple as movement in a normal emacs text buffer.  Most
 128 cursor movement bindings are the same (ie. Use \\[hexl-backward-char], \\[hexl-forward-char], \\[hexl-next-line], and \\[hexl-previous-line]
 129 to move the cursor left, right, down, and up).
 130
 131 Advanced cursor movement commands (ala \\[hexl-beginning-of-line], \\[hexl-end-of-line], \\[hexl-beginning-of-buffer], and \\[hexl-end-of-buffer]) are
 132 also supported.
 133
 134 There are several ways to change text in hexl mode:
 135
 136 ASCII characters (character between space (0x20) and tilde (0x7E)) are
 137 bound to self-insert so you can simply type the character and it will
 138 insert itself (actually overstrike) into the buffer.
 139
 140 \\[hexl-quoted-insert] followed by another keystroke allows you to insert the key even if
 141 it isn't bound to self-insert.  An octal number can be supplied in place
 142 of another key to insert the octal number's ASCII representation.
 143
 144 \\[hexl-insert-hex-char] will insert a given hexadecimal value (if it is between 0 and 0xFF)
 145 into the buffer at the current point.
 146
 147 \\[hexl-insert-octal-char] will insert a given octal value (if it is between 0 and 0377)
 148 into the buffer at the current point.
 149
 150 \\[hexl-insert-decimal-char] will insert a given decimal value (if it is between 0 and 255)
 151 into the buffer at the current point.
 152
 153 \\[hexl-mode-exit] will exit hexl-mode.
 154
 155 Note: saving the file with any of the usual Emacs commands
 156 will actually convert it back to binary format while saving.
 157
 158 You can use \\[hexl-find-file] to visit a file in hexl-mode.
 159
 160 \\[describe-bindings] for advanced commands."
 161   (interactive "p")
 162   (if (eq major-mode 'hexl-mode)
 163       (error "You are already in hexl mode")
 164
 165     ;; We do not turn off the old major mode; instead we just
 166     ;; override most of it.  That way, we can restore it perfectly.
 167     (make-local-variable 'hexl-mode-old-local-map)
 168     (setq hexl-mode-old-local-map (current-local-map))
 169     (use-local-map hexl-mode-map)
 170
 171     (make-local-variable 'hexl-mode-old-mode-name)
 172     (setq hexl-mode-old-mode-name mode-name)
 173     (setq mode-name "Hexl")
 174
 175     (make-local-variable 'hexl-mode-old-major-mode)
 176     (setq hexl-mode-old-major-mode major-mode)
 177     (setq major-mode 'hexl-mode)
 178
 179     (make-local-variable 'hexl-mode-old-syntax-table)
 180     (setq hexl-mode-old-syntax-table (syntax-table))
 181     (set-syntax-table (standard-syntax-table))
 182
 183     (make-local-variable 'hexl-mode-old-write-contents-hooks)
 184     (setq hexl-mode-old-write-contents-hooks write-contents-hooks)
 185     (make-local-variable 'write-contents-hooks)
 186     (add-hook 'write-contents-hooks 'hexl-save-buffer)
 187
 188     (make-local-variable 'hexl-mode-old-require-final-newline)
 189     (setq hexl-mode-old-require-final-newline require-final-newline)
 190     (make-local-variable 'require-final-newline)
 191     (setq require-final-newline nil)
 192
 193     ;; Add hooks to rehexlify or dehexlify on various events.
 194     (make-local-hook 'after-revert-hook)
 195     (add-hook 'after-revert-hook 'hexl-after-revert-hook nil t)
 196
 197     (make-local-hook 'change-major-mode-hook)
 198     (add-hook 'change-major-mode-hook 'hexl-maybe-dehexlify-buffer nil t)
 199
 200     (make-local-variable 'hexl-max-address)
 201
 202     (let ((modified (buffer-modified-p))
 203           (inhibit-read-only t)
 204           (original-point (1- (point))))
 205       (and (eobp) (not (bobp))
 206            (setq original-point (1- original-point)))
 207       (if (not (or (eq arg 1) (not arg)))
 208           ;; if no argument then we guess at hexl-max-address
 209           (setq hexl-max-address (+ (* (/ (1- (buffer-size)) 68) 16) 15))
 210         (setq hexl-max-address (1- (buffer-size)))
 211         (hexlify-buffer)
 212         (set-buffer-modified-p modified)
 213         (hexl-goto-address original-point)))))
 214
 215 (defun hexl-after-revert-hook ()
 216   (hexlify-buffer)
 217   (set-buffer-modified-p nil))
 218
 219 (defvar hexl-in-save-buffer nil)
 220
 221 (defun hexl-save-buffer ()
 222   "Save a hexl format buffer as binary in visited file if modified."
 223   (interactive)
 224   (if hexl-in-save-buffer nil
 225     (set-buffer-modified-p (if (buffer-modified-p)
 226                                (save-excursion
 227                                  (let ((buf (generate-new-buffer " hexl"))
 228                                        (name (buffer-name))
 229                                        (file-name (buffer-file-name))
 230                                        (start (point-min))
 231                                        (end (point-max))
 232                                        modified)
 233                                    (set-buffer buf)
 234                                    (insert-buffer-substring name start end)
 235                                    (set-buffer name)
 236                                    (dehexlify-buffer)
 237                                    ;; Prevent infinite recursion.
 238                                    (let ((hexl-in-save-buffer t)
 239                                          (buffer-file-type t)) ; for ms-dos
 240                                      (save-buffer))
 241                                    (setq modified (buffer-modified-p))
 242                                    (delete-region (point-min) (point-max))
 243                                    (insert-buffer-substring buf start end)
 244                                    (kill-buffer buf)
 245                                    modified))
 246                              (message "(No changes need to be saved)")
 247                              nil))
 248     ;; Return t to indicate we have saved t
 249     t))
 250
 251 ;;;###autoload
 252 (defun hexl-find-file (filename)
 253   "Edit file FILENAME in hexl-mode.
 254 Switch to a buffer visiting file FILENAME, creating one in none exists."
 255   (interactive "fFilename: ")
 256   (if (or (eq system-type 'ms-dos) (eq system-type 'windows-nt))
 257       (find-file-binary filename)
 258     (find-file filename))
 259   (if (not (eq major-mode 'hexl-mode))
 260       (hexl-mode)))
 261
 262 (defun hexl-mode-exit (&optional arg)
 263   "Exit Hexl mode, returning to previous mode.
 264 With arg, don't unhexlify buffer."
 265   (interactive "p")
 266   (if (or (eq arg 1) (not arg))
 267       (let ((modified (buffer-modified-p))
 268             (inhibit-read-only t)
 269             (original-point (1+ (hexl-current-address))))
 270         (dehexlify-buffer)
 271         (remove-hook 'write-contents-hook 'hexl-save-buffer)
 272         (set-buffer-modified-p modified)
 273         (goto-char original-point)))
 274
 275   (remove-hook 'after-revert-hook 'hexl-after-revert-hook t)
 276   (remove-hook 'change-major-mode-hook 'hexl-maybe-dehexlify-buffer t)
 277
 278   (setq write-contents-hooks hexl-mode-old-write-contents-hooks)
 279   (setq require-final-newline hexl-mode-old-require-final-newline)
 280   (setq mode-name hexl-mode-old-mode-name)
 281   (use-local-map hexl-mode-old-local-map)
 282   (set-syntax-table hexl-mode-old-syntax-table)
 283   (setq major-mode hexl-mode-old-major-mode)
 284   (force-mode-line-update))
 285
 286 (defun hexl-maybe-dehexlify-buffer ()
 287   "Convert a hexl format buffer to binary.
 288 Ask the user for confirmation."
 289   (if (y-or-n-p "Convert contents back to binary format? ")
 290       (let ((modified (buffer-modified-p))
 291             (inhibit-read-only t)
 292             (original-point (1+ (hexl-current-address))))
 293         (dehexlify-buffer)
 294         (remove-hook 'write-contents-hook 'hexl-save-buffer)
 295         (set-buffer-modified-p modified)
 296         (goto-char original-point))))
 297
 298 (defun hexl-current-address (&optional validate)
 299   "Return current hexl-address."
 300   (interactive)
 301   (let ((current-column (- (% (point) 68) 11))
 302         (hexl-address 0))
 303     (if (< current-column 0)
 304         (if validate
 305             (error "Point is not on a character in the file")
 306           (setq current-column 0)))
 307     (setq hexl-address
 308           (+ (* (/ (point) 68) 16)
 309              (if (>= current-column 41)
 310                  (- current-column 41)
 311                (/ (- current-column  (/ current-column 5)) 2))))
 312     hexl-address))
 313
 314 (defun hexl-address-to-marker (address)
 315   "Return marker for ADDRESS."
 316   (interactive "nAddress: ")
 317   (+ (* (/ address 16) 68) 11 (/ (* (% address 16) 5) 2)))
 318
 319 (defun hexl-goto-address (address)
 320   "Goto hexl-mode (decimal) address ADDRESS.
 321 Signal error if ADDRESS out of range."
 322   (interactive "nAddress: ")
 323   (if (or (< address 0) (> address hexl-max-address))
 324           (error "Out of hexl region."))
 325   (goto-char (hexl-address-to-marker address)))
 326
 327 (defun hexl-goto-hex-address (hex-address)
 328   "Go to hexl-mode address (hex string) HEX-ADDRESS.
 329 Signal error if HEX-ADDRESS is out of range."
 330   (interactive "sHex Address: ")
 331   (hexl-goto-address (hexl-hex-string-to-integer hex-address)))
 332
 333 (defun hexl-hex-string-to-integer (hex-string)
 334   "Return decimal integer for HEX-STRING."
 335   (interactive "sHex number: ")
 336   (let ((hex-num 0))
 337     (while (not (equal hex-string ""))
 338       (setq hex-num (+ (* hex-num 16)
 339                        (hexl-hex-char-to-integer (string-to-char hex-string))))
 340       (setq hex-string (substring hex-string 1)))
 341     hex-num))
 342
 343 (defun hexl-octal-string-to-integer (octal-string)
 344   "Return decimal integer for OCTAL-STRING."
 345   (interactive "sOctal number: ")
 346   (let ((oct-num 0))
 347     (while (not (equal octal-string ""))
 348       (setq oct-num (+ (* oct-num 8)
 349                        (hexl-oct-char-to-integer
 350                         (string-to-char octal-string))))
 351       (setq octal-string (substring octal-string 1)))
 352     oct-num))
 353
 354 ;; move point functions
 355
 356 (defun hexl-backward-char (arg)
 357   "Move to left ARG bytes (right if ARG negative) in hexl-mode."
 358   (interactive "p")
 359   (hexl-goto-address (- (hexl-current-address) arg)))
 360
 361 (defun hexl-forward-char (arg)
 362   "Move right ARG bytes (left if ARG negative) in hexl-mode."
 363   (interactive "p")
 364   (hexl-goto-address (+ (hexl-current-address) arg)))
 365
 366 (defun hexl-backward-short (arg)
 367   "Move to left ARG shorts (right if ARG negative) in hexl-mode."
 368   (interactive "p")
 369   (hexl-goto-address (let ((address (hexl-current-address)))
 370                        (if (< arg 0)
 371                            (progn
 372                              (setq arg (- arg))
 373                              (while (> arg 0)
 374                                (if (not (equal address (logior address 3)))
 375                                    (if (> address hexl-max-address)
 376                                        (progn
 377                                          (message "End of buffer.")
 378                                          (setq address hexl-max-address))
 379                                      (setq address (logior address 3)))
 380                                  (if (> address hexl-max-address)
 381                                      (progn
 382                                        (message "End of buffer.")
 383                                        (setq address hexl-max-address))
 384                                    (setq address (+ address 4))))
 385                                (setq arg (1- arg)))
 386                              (if (> address hexl-max-address)
 387                                  (progn
 388                                    (message "End of buffer.")
 389                                    (setq address hexl-max-address))
 390                                (setq address (logior address 3))))
 391                          (while (> arg 0)
 392                            (if (not (equal address (logand address -4)))
 393                                (setq address (logand address -4))
 394                              (if (not (equal address 0))
 395                                  (setq address (- address 4))
 396                                (message "Beginning of buffer.")))
 397                            (setq arg (1- arg))))
 398                        address)))
 399
 400 (defun hexl-forward-short (arg)
 401   "Move right ARG shorts (left if ARG negative) in hexl-mode."
 402   (interactive "p")
 403   (hexl-backward-short (- arg)))
 404
 405 (defun hexl-backward-word (arg)
 406   "Move to left ARG words (right if ARG negative) in hexl-mode."
 407   (interactive "p")
 408   (hexl-goto-address (let ((address (hexl-current-address)))
 409                        (if (< arg 0)
 410                            (progn
 411                              (setq arg (- arg))
 412                              (while (> arg 0)
 413                                (if (not (equal address (logior address 7)))
 414                                    (if (> address hexl-max-address)
 415                                        (progn
 416                                          (message "End of buffer.")
 417                                          (setq address hexl-max-address))
 418                                      (setq address (logior address 7)))
 419                                  (if (> address hexl-max-address)
 420                                      (progn
 421                                        (message "End of buffer.")
 422                                        (setq address hexl-max-address))
 423                                    (setq address (+ address 8))))
 424                                (setq arg (1- arg)))
 425                              (if (> address hexl-max-address)
 426                                  (progn
 427                                    (message "End of buffer.")
 428                                    (setq address hexl-max-address))
 429                                (setq address (logior address 7))))
 430                          (while (> arg 0)
 431                            (if (not (equal address (logand address -8)))
 432                                (setq address (logand address -8))
 433                              (if (not (equal address 0))
 434                                  (setq address (- address 8))
 435                                (message "Beginning of buffer.")))
 436                            (setq arg (1- arg))))
 437                        address)))
 438
 439 (defun hexl-forward-word (arg)
 440   "Move right ARG words (left if ARG negative) in hexl-mode."
 441   (interactive "p")
 442   (hexl-backward-word (- arg)))
 443
 444 (defun hexl-previous-line (arg)
 445   "Move vertically up ARG lines [16 bytes] (down if ARG negative) in hexl-mode.
 446 If there is byte at the target address move to the last byte in that line."
 447   (interactive "p")
 448   (hexl-next-line (- arg)))
 449
 450 (defun hexl-next-line (arg)
 451   "Move vertically down ARG lines [16 bytes] (up if ARG negative) in hexl-mode.
 452 If there is no byte at the target address move to the last byte in that line."
 453   (interactive "p")
 454   (hexl-goto-address (let ((address (+ (hexl-current-address) (* arg 16))))
 455                        (if (and (< arg 0) (< address 0))
 456                                 (progn (message "Out of hexl region.")
 457                                        (setq address
 458                                              (% (hexl-current-address) 16)))
 459                          (if (and (> address hexl-max-address)
 460                                   (< (% hexl-max-address 16) (% address 16)))
 461                              (setq address hexl-max-address)
 462                            (if (> address hexl-max-address)
 463                                (progn (message "Out of hexl region.")
 464                                       (setq
 465                                        address
 466                                        (+ (logand hexl-max-address -16)
 467                                           (% (hexl-current-address) 16)))))))
 468                        address)))
 469
 470 (defun hexl-beginning-of-buffer (arg)
 471   "Move to the beginning of the hexl buffer.
 472 Leaves `hexl-mark' at previous position.
 473 With prefix arg N, puts point N bytes of the way from the true beginning."
 474   (interactive "p")
 475   (push-mark (point))
 476   (hexl-goto-address (+ 0 (1- arg))))
 477
 478 (defun hexl-end-of-buffer (arg)
 479   "Go to `hexl-max-address' minus ARG."
 480   (interactive "p")
 481   (push-mark (point))
 482   (hexl-goto-address (- hexl-max-address (1- arg))))
 483
 484 (defun hexl-beginning-of-line ()
 485   "Goto beginning of line in hexl mode."
 486   (interactive)
 487   (goto-char (+ (* (/ (point) 68) 68) 11)))
 488
 489 (defun hexl-end-of-line ()
 490   "Goto end of line in hexl mode."
 491   (interactive)
 492   (hexl-goto-address (let ((address (logior (hexl-current-address) 15)))
 493                        (if (> address hexl-max-address)
 494                            (setq address hexl-max-address))
 495                        address)))
 496
 497 (defun hexl-scroll-down (arg)
 498   "Scroll hexl buffer window upward ARG lines; or near full window if no ARG."
 499   (interactive "P")
 500   (if (null arg)
 501       (setq arg (1- (window-height)))
 502     (setq arg (prefix-numeric-value arg)))
 503   (hexl-scroll-up (- arg)))
 504
 505 (defun hexl-scroll-up (arg)
 506   "Scroll hexl buffer window upward ARG lines; or near full window if no ARG."
 507   (interactive "P")
 508   (if (null arg)
 509       (setq arg (1- (window-height)))
 510     (setq arg (prefix-numeric-value arg)))
 511   (let ((movement (* arg 16))
 512         (address (hexl-current-address)))
 513     (if (or (> (+ address movement) hexl-max-address)
 514             (< (+ address movement) 0))
 515         (message "Out of hexl region.")
 516       (hexl-goto-address (+ address movement))
 517       (recenter 0))))
 518
 519 (defun hexl-beginning-of-1k-page ()
 520   "Go to beginning of 1k boundary."
 521   (interactive)
 522   (hexl-goto-address (logand (hexl-current-address) -1024)))
 523
 524 (defun hexl-end-of-1k-page ()
 525   "Go to end of 1k boundary."
 526   (interactive)
 527   (hexl-goto-address (let ((address (logior (hexl-current-address) 1023)))
 528                        (if (> address hexl-max-address)
 529                            (setq address hexl-max-address))
 530                        address)))
 531
 532 (defun hexl-beginning-of-512b-page ()
 533   "Go to beginning of 512 byte boundary."
 534   (interactive)
 535   (hexl-goto-address (logand (hexl-current-address) -512)))
 536
 537 (defun hexl-end-of-512b-page ()
 538   "Go to end of 512 byte boundary."
 539   (interactive)
 540   (hexl-goto-address (let ((address (logior (hexl-current-address) 511)))
 541                        (if (> address hexl-max-address)
 542                            (setq address hexl-max-address))
 543                        address)))
 544
 545 (defun hexl-quoted-insert (arg)
 546   "Read next input character and insert it.
 547 Useful for inserting control characters.
 548 You may also type up to 3 octal digits, to insert a character with that code"
 549   (interactive "p")
 550   (hexl-insert-char (read-quoted-char) arg))
 551
 552 ;00000000: 0011 2233 4455 6677 8899 aabb ccdd eeff  0123456789ABCDEF
 553
 554 ;;;###autoload
 555 (defun hexlify-buffer ()
 556   "Convert a binary buffer to hexl format."
 557   (interactive)
 558   (let ((binary-process-output nil) ; for Ms-Dos
 559         (binary-process-input t))
 560     (shell-command-on-region (point-min) (point-max) hexlify-command t)))
 561
 562 (defun dehexlify-buffer ()
 563   "Convert a hexl format buffer to binary."
 564   (interactive)
 565   (let ((binary-process-output t) ; for Ms-Dos
 566         (binary-process-input nil))
 567     (shell-command-on-region (point-min) (point-max) dehexlify-command t)))
 568
 569 (defun hexl-char-after-point ()
 570   "Return char for ASCII hex digits at point."
 571   (hexl-htoi (char-after (point))
 572              (char-after (1+ (point)))))
 573
 574 (defun hexl-htoi (lh rh)
 575   "Hex (char) LH (char) RH to integer."
 576     (+ (* (hexl-hex-char-to-integer lh) 16)
 577        (hexl-hex-char-to-integer rh)))
 578
 579 (defun hexl-hex-char-to-integer (character)
 580   "Take a char and return its value as if it was a hex digit."
 581   (if (and (>= character ?0) (<= character ?9))
 582       (- character ?0)
 583     (let ((ch (logior character 32)))
 584       (if (and (>= ch ?a) (<= ch ?f))
 585           (- ch (- ?a 10))
 586         (error (format "Invalid hex digit `%c'." ch))))))
 587
 588 (defun hexl-oct-char-to-integer (character)
 589   "Take a char and return its value as if it was a octal digit."
 590   (if (and (>= character ?0) (<= character ?7))
 591       (- character ?0)
 592     (error (format "Invalid octal digit `%c'." character))))
 593
 594 (defun hexl-printable-character (ch)
 595   "Return a displayable string for character CH."
 596   (format "%c" (if hexl-iso
 597                    (if (or (< ch 32) (and (>= ch 127) (< ch 160)))
 598                        46
 599                      ch)
 600                  (if (or (< ch 32) (>= ch 127))
 601                      46
 602                    ch))))
 603
 604 (defun hexl-self-insert-command (arg)
 605   "Insert this character."
 606   (interactive "p")
 607   (hexl-insert-char last-command-char arg))
 608
 609 (defun hexl-insert-char (ch num)
 610   "Insert a character in a hexl buffer."
 611   (let ((address (hexl-current-address t)))
 612     (while (> num 0)
 613       (let ((hex-position
 614              (+ (* (/ address 16) 68)
 615                 11
 616                 (* 2 (% address 16))
 617                 (/ (% address 16) 2)))
 618             (ascii-position
 619              (+ (* (/ address 16) 68) 52 (% address 16)))
 620             at-ascii-position)
 621         (if (= (point) ascii-position)
 622             (setq at-ascii-position t))
 623         (goto-char hex-position)
 624         (delete-char 2)
 625         (insert (format "%02x" ch))
 626         (goto-char ascii-position)
 627         (delete-char 1)
 628         (insert (hexl-printable-character ch))
 629         (or (eq address hexl-max-address)
 630             (setq address (1+ address)))
 631         (hexl-goto-address address)
 632         (if at-ascii-position
 633             (progn
 634               (beginning-of-line)
 635               (forward-char 51)
 636               (forward-char (% address 16)))))
 637       (setq num (1- num)))))
 638
 639 ;; hex conversion
 640
 641 (defun hexl-insert-hex-char (arg)
 642   "Insert a ASCII char ARG times at point for a given hexadecimal number."
 643   (interactive "p")
 644   (let ((num (hexl-hex-string-to-integer (read-string "Hex number: "))))
 645     (if (or (> num 255) (< num 0))
 646         (error "Hex number out of range.")
 647       (hexl-insert-char num arg))))
 648
 649 (defun hexl-insert-decimal-char (arg)
 650   "Insert a ASCII char ARG times at point for a given decimal number."
 651   (interactive "p")
 652   (let ((num (string-to-int (read-string "Decimal Number: "))))
 653     (if (or (> num 255) (< num 0))
 654         (error "Decimal number out of range.")
 655       (hexl-insert-char num arg))))
 656
 657 (defun hexl-insert-octal-char (arg)
 658   "Insert a ASCII char ARG times at point for a given octal number."
 659   (interactive "p")
 660   (let ((num (hexl-octal-string-to-integer (read-string "Octal Number: "))))
 661     (if (or (> num 255) (< num 0))
 662         (error "Decimal number out of range.")
 663       (hexl-insert-char num arg))))
 664
 665 ;; startup stuff.
 666
 667 (if hexl-mode-map
 668     nil
 669     (setq hexl-mode-map (make-sparse-keymap))
 670
 671     (define-key hexl-mode-map [left] 'hexl-backward-char)
 672     (define-key hexl-mode-map [right] 'hexl-forward-char)
 673     (define-key hexl-mode-map [up] 'hexl-previous-line)
 674     (define-key hexl-mode-map [down] 'hexl-next-line)
 675     (define-key hexl-mode-map [M-left] 'hexl-backward-short)
 676     (define-key hexl-mode-map [M-right] 'hexl-forward-short)
 677     (define-key hexl-mode-map [next] 'hexl-scroll-up)
 678     (define-key hexl-mode-map [prev] 'hexl-scroll-down)
 679
 680     (define-key hexl-mode-map "\C-a" 'hexl-beginning-of-line)
 681     (define-key hexl-mode-map "\C-b" 'hexl-backward-char)
 682     (define-key hexl-mode-map "\C-d" 'undefined)
 683     (define-key hexl-mode-map "\C-e" 'hexl-end-of-line)
 684     (define-key hexl-mode-map "\C-f" 'hexl-forward-char)
 685
 686     (if (not (eq (key-binding (char-to-string help-char)) 'help-command))
 687         (define-key hexl-mode-map (char-to-string help-char) 'undefined))
 688
 689     (define-key hexl-mode-map "\C-i" 'hexl-self-insert-command)
 690     (define-key hexl-mode-map "\C-j" 'hexl-self-insert-command)
 691     (define-key hexl-mode-map "\C-k" 'undefined)
 692     (define-key hexl-mode-map "\C-m" 'hexl-self-insert-command)
 693     (define-key hexl-mode-map "\C-n" 'hexl-next-line)
 694     (define-key hexl-mode-map "\C-o" 'undefined)
 695     (define-key hexl-mode-map "\C-p" 'hexl-previous-line)
 696     (define-key hexl-mode-map "\C-q" 'hexl-quoted-insert)
 697     (define-key hexl-mode-map "\C-t" 'undefined)
 698     (define-key hexl-mode-map "\C-v" 'hexl-scroll-up)
 699     (define-key hexl-mode-map "\C-w" 'undefined)
 700     (define-key hexl-mode-map "\C-y" 'undefined)
 701
 702     (let ((ch 32))
 703       (while (< ch 127)
 704         (define-key hexl-mode-map (format "%c" ch) 'hexl-self-insert-command)
 705         (setq ch (1+ ch))))
 706
 707     (define-key hexl-mode-map "\e\C-a" 'hexl-beginning-of-512b-page)
 708     (define-key hexl-mode-map "\e\C-b" 'hexl-backward-short)
 709     (define-key hexl-mode-map "\e\C-c" 'undefined)
 710     (define-key hexl-mode-map "\e\C-d" 'hexl-insert-decimal-char)
 711     (define-key hexl-mode-map "\e\C-e" 'hexl-end-of-512b-page)
 712     (define-key hexl-mode-map "\e\C-f" 'hexl-forward-short)
 713     (define-key hexl-mode-map "\e\C-g" 'undefined)
 714     (define-key hexl-mode-map "\e\C-h" 'undefined)
 715     (define-key hexl-mode-map "\e\C-i" 'undefined)
 716     (define-key hexl-mode-map "\e\C-j" 'undefined)
 717     (define-key hexl-mode-map "\e\C-k" 'undefined)
 718     (define-key hexl-mode-map "\e\C-l" 'undefined)
 719     (define-key hexl-mode-map "\e\C-m" 'undefined)
 720     (define-key hexl-mode-map "\e\C-n" 'undefined)
 721     (define-key hexl-mode-map "\e\C-o" 'hexl-insert-octal-char)
 722     (define-key hexl-mode-map "\e\C-p" 'undefined)
 723     (define-key hexl-mode-map "\e\C-q" 'undefined)
 724     (define-key hexl-mode-map "\e\C-r" 'undefined)
 725     (define-key hexl-mode-map "\e\C-s" 'undefined)
 726     (define-key hexl-mode-map "\e\C-t" 'undefined)
 727     (define-key hexl-mode-map "\e\C-u" 'undefined)
 728
 729     (define-key hexl-mode-map "\e\C-w" 'undefined)
 730     (define-key hexl-mode-map "\e\C-x" 'hexl-insert-hex-char)
 731     (define-key hexl-mode-map "\e\C-y" 'undefined)
 732
 733     (define-key hexl-mode-map "\ea" 'undefined)
 734     (define-key hexl-mode-map "\eb" 'hexl-backward-word)
 735     (define-key hexl-mode-map "\ec" 'undefined)
 736     (define-key hexl-mode-map "\ed" 'undefined)
 737     (define-key hexl-mode-map "\ee" 'undefined)
 738     (define-key hexl-mode-map "\ef" 'hexl-forward-word)
 739     (define-key hexl-mode-map "\eg" 'hexl-goto-hex-address)
 740     (define-key hexl-mode-map "\eh" 'undefined)
 741     (define-key hexl-mode-map "\ei" 'undefined)
 742     (define-key hexl-mode-map "\ej" 'hexl-goto-address)
 743     (define-key hexl-mode-map "\ek" 'undefined)
 744     (define-key hexl-mode-map "\el" 'undefined)
 745     (define-key hexl-mode-map "\em" 'undefined)
 746     (define-key hexl-mode-map "\en" 'undefined)
 747     (define-key hexl-mode-map "\eo" 'undefined)
 748     (define-key hexl-mode-map "\ep" 'undefined)
 749     (define-key hexl-mode-map "\eq" 'undefined)
 750     (define-key hexl-mode-map "\er" 'undefined)
 751     (define-key hexl-mode-map "\es" 'undefined)
 752     (define-key hexl-mode-map "\et" 'undefined)
 753     (define-key hexl-mode-map "\eu" 'undefined)
 754     (define-key hexl-mode-map "\ev" 'hexl-scroll-down)
 755     (define-key hexl-mode-map "\ey" 'undefined)
 756     (define-key hexl-mode-map "\ez" 'undefined)
 757     (define-key hexl-mode-map "\e<" 'hexl-beginning-of-buffer)
 758     (define-key hexl-mode-map "\e>" 'hexl-end-of-buffer)
 759
 760     (define-key hexl-mode-map "\C-c\C-c" 'hexl-mode-exit)
 761
 762     (define-key hexl-mode-map "\C-x[" 'hexl-beginning-of-1k-page)
 763     (define-key hexl-mode-map "\C-x]" 'hexl-end-of-1k-page)
 764     (define-key hexl-mode-map "\C-x\C-p" 'undefined)
 765     (define-key hexl-mode-map "\C-x\C-s" 'hexl-save-buffer)
 766     (define-key hexl-mode-map "\C-x\C-t" 'undefined))
 767
 768 ;;; hexl.el ends here