lisp/international/encoded-kb.el

   1 ;;; encoded-kb.el --- Handler to input multibyte characters encoded somehow
   2
   3 ;; Copyright (C) 1995 Electrotechnical Laboratory, JAPAN.
   4 ;; Licensed to the Free Software Foundation.
   5
   6 ;; This file is part of GNU Emacs.
   7
   8 ;; GNU Emacs is free software; you can redistribute it and/or modify
   9 ;; it under the terms of the GNU General Public License as published by
  10 ;; the Free Software Foundation; either version 2, or (at your option)
  11 ;; any later version.
  12
  13 ;; GNU Emacs is distributed in the hope that it will be useful,
  14 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 ;; GNU General Public License for more details.
  17
  18 ;; You should have received a copy of the GNU General Public License
  19 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  20 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  21 ;; Boston, MA 02111-1307, USA.
  22
  23 (defvar encoded-kbd-mode nil
  24   "Non-nil if in Encoded-kbd minor mode.")
  25 (put 'encoded-kbd-mode 'permanent-local t)
  26
  27 (let ((slot (assq 'encoded-kbd-mode minor-mode-alist))
  28       (name " Encoded-kbd"))
  29   (if slot
  30       (setcar (cdr slot) name)
  31     (setq minor-mode-alist
  32           (cons '(encoded-kbd-mode " Encoded-kbd") minor-mode-alist))))
  33
  34 (defconst encoded-kbd-mode-map (make-sparse-keymap)
  35   "Keymap for Encoded-kbd minor mode.")
  36
  37 (let ((slot (assq 'encoded-kbd-mode minor-mode-map-alist)))
  38   (if slot
  39       (setcdr slot encoded-kbd-mode-map)
  40     (setq minor-mode-map-alist
  41           (cons (cons 'encoded-kbd-mode encoded-kbd-mode-map)
  42                 minor-mode-map-alist))))
  43
  44 ;; Subsidiary keymaps for handling ISO2022 escape sequences.
  45
  46 (defvar encoded-kbd-iso2022-esc-map
  47   (let ((map (make-sparse-keymap)))
  48     (define-key map "$" 'encoded-kbd-iso2022-esc-dollar-prefix)
  49     (define-key map "(" 'encoded-kbd-iso2022-designation-prefix)
  50     (define-key map ")" 'encoded-kbd-iso2022-designation-prefix)
  51     (define-key map "," 'encoded-kbd-iso2022-designation-prefix)
  52     (define-key map "-" 'encoded-kbd-iso2022-designation-prefix)
  53     map)
  54   "Keymap for handling ESC code in Encoded-kbd mode.")
  55 (fset 'encoded-kbd-iso2022-esc-prefix encoded-kbd-iso2022-esc-map)
  56
  57 (defvar encoded-kbd-iso2022-esc-dollar-map
  58   (let ((map (make-sparse-keymap)))
  59     (define-key map "(" 'encoded-kbd-iso2022-designation-prefix)
  60     (define-key map ")" 'encoded-kbd-iso2022-designation-prefix)
  61     (define-key map "," 'encoded-kbd-iso2022-designation-prefix)
  62     (define-key map "-" 'encoded-kbd-iso2022-designation-prefix)
  63     (define-key map "@" 'encoded-kbd-iso2022-designation)
  64     (define-key map "A" 'encoded-kbd-iso2022-designation)
  65     (define-key map "B" 'encoded-kbd-iso2022-designation)
  66     map)
  67   "Keymap for handling ESC $ sequence in Encoded-kbd mode.")
  68 (fset 'encoded-kbd-iso2022-esc-dollar-prefix
  69       encoded-kbd-iso2022-esc-dollar-map)
  70
  71 (defvar encoded-kbd-iso2022-designation-map
  72   (let ((map (make-sparse-keymap))
  73         (l charset-list)
  74         final-char)
  75     (while l
  76       (setq final-char (charset-iso-final-char (car l)))
  77       (if final-char
  78           (define-key map (char-to-string final-char)
  79             'encoded-kbd-iso2022-designation))
  80       (setq l (cdr l)))
  81     map)
  82   "Keymap for handling ISO2022 designation sequence in Encoded-kbd mode.")
  83 (fset 'encoded-kbd-iso2022-designation-prefix
  84       encoded-kbd-iso2022-designation-map)
  85
  86 (defvar encoded-kbd-iso2022-non-ascii-map
  87   (let ((map (make-keymap))
  88         (i 32))
  89     (while (< i 128)
  90       (define-key map (char-to-string i) 'encoded-kbd-self-insert-iso2022-7bit)
  91       (setq i (1+ i)))
  92     (define-key map "\e" 'encoded-kbd-iso2022-esc-prefix)
  93     (setq i 160)
  94     (while (< i 256)
  95       (define-key map (vector i) 'encoded-kbd-handle-8bit)
  96       (setq i (1+ i)))
  97     map)
  98   "Keymap for handling non-ASCII character set in Encoded-kbd mode.")
  99
 100 ;; One of the symbols `sjis', `iso2022-7', `iso2022-8', or `big5' to
 101 ;; denote what kind of coding-system we are now handling in
 102 ;; Encoded-kbd mode.
 103 (defvar encoded-kbd-coding nil)
 104
 105 ;; Keep information of designation state of ISO2022 encoding.  When
 106 ;; Encoded-kbd mode is on, this is set to a vector of length 4, the
 107 ;; elements are character sets currently designated to graphic
 108 ;; registers 0 thru 3.
 109
 110 (defvar encoded-kbd-iso2022-designations nil)
 111 (put 'encoded-kbd-iso2022-designations 'permanent-local t)
 112
 113 ;; Keep information of invocation state of ISO2022 encoding.  When
 114 ;; Encoded-kbd mode is on, this is set to a vector of length 3,
 115 ;; graphic register numbers currently invoked to graphic plane 1 and
 116 ;; 2, and a single shifted graphic register number.
 117
 118 (defvar encoded-kbd-iso2022-invocations nil)
 119 (put 'encoded-kbd-iso2022-invocations 'permanent-local t)
 120
 121 (defun encoded-kbd-iso2022-designation ()
 122   "Do ISO2022 designation according to the current key in Encoded-kbd mode.
 123 The following key sequence may cause multilingual text insertion."
 124   (interactive)
 125   (let ((key-seq (this-command-keys))
 126         (prev-g0-charset (aref encoded-kbd-iso2022-designations
 127                                (aref encoded-kbd-iso2022-invocations 0)))
 128         intermediate-char final-char
 129         reg dimension chars charset)
 130     (if (= (length key-seq) 4)
 131         ;; ESC $ <intermediate-char> <final-char>
 132         (setq intermediate-char (aref key-seq 2)
 133               dimension 2
 134               chars (if (< intermediate-char ?,) 94 96)
 135               final-char (aref key-seq 3)
 136               reg (mod intermediate-char 4))
 137       (if (= (aref key-seq 1) ?$)
 138           ;; ESC $ <final-char>
 139           (setq dimension 2
 140                 chars 94
 141                 final-char (aref key-seq 2)
 142                 reg 0)
 143         ;; ESC <intermediate-char> <final-char>
 144         (setq intermediate-char (aref key-seq 1)
 145               dimension 1
 146               chars (if (< intermediate-char ?,) 94 96)
 147               final-char (aref key-seq 2)
 148               reg (mod intermediate-char 4))))
 149     (if (setq charset (iso-charset dimension chars final-char))
 150         (aset encoded-kbd-iso2022-designations reg charset)
 151       (error "Character set of DIMENSION %s, CHARS %s, FINAL-CHAR `%c' is not supported"
 152              dimension chars final-char))
 153
 154     (if (memq (aref encoded-kbd-iso2022-designations
 155                     (aref encoded-kbd-iso2022-invocations 0))
 156               '(ascii latin-jisx0201))
 157         ;; Graphic plane 0 (0x20..0x7f) is for ASCII.  We don't have
 158         ;; to handle characters in this range specially.
 159         (if (not (memq prev-g0-charset '(ascii latin-jisx0201)))
 160             ;; We must exit recursive edit now.
 161             (throw 'exit nil))
 162       ;; Graphic plane 0 is for non-ASCII.
 163       (if (memq prev-g0-charset '(ascii latin-jisx0201))
 164           ;; We must handle keys specially.
 165           (let ((overriding-local-map encoded-kbd-iso2022-non-ascii-map))
 166             (recursive-edit))))))
 167
 168 (defun encoded-kbd-handle-8bit ()
 169   "Handle an 8-bit character entered in Encoded-kbd mode."
 170   (interactive)
 171   (cond ((eq encoded-kbd-coding 'iso2022-7)
 172          (error "Can't handle the character code %d" last-command-char))
 173
 174         ((eq encoded-kbd-coding 'iso2022-8)
 175          (cond ((= last-command-char ?\216)
 176                 (aset encoded-kbd-iso2022-invocations 2 2))
 177
 178                ((= last-command-char ?\217)
 179                 (aset encoded-kbd-iso2022-invocations 2 3))
 180
 181                ((>= last-command-char ?\240)
 182                 (encoded-kbd-self-insert-iso2022-8bit))
 183
 184                (t
 185                 (error "Can't handle the character code %d"
 186                        last-command-char))))
 187
 188         ((eq encoded-kbd-coding 'sjis)
 189          (encoded-kbd-self-insert-sjis))
 190
 191         (t
 192          (encoded-kbd-self-insert-big5))))
 193
 194 (defun encoded-kbd-self-insert-iso2022-7bit ()
 195   (interactive)
 196   (let* ((charset (aref encoded-kbd-iso2022-designations
 197                         (or (aref encoded-kbd-iso2022-invocations 2)
 198                             (aref encoded-kbd-iso2022-invocations 0))))
 199          (char (if (= (charset-dimension charset) 1)
 200                    (make-char charset last-command-char)
 201                  (make-char charset last-command-char (read-char-exclusive)))))
 202     (aset encoded-kbd-iso2022-invocations 2 nil)
 203     (setq unread-command-events (cons char unread-command-events))))
 204
 205 (defun encoded-kbd-self-insert-iso2022-8bit ()
 206   (interactive)
 207   (cond
 208    ((= last-command-char ?\216)         ; SS2 (Single Shift 2)
 209     (aset encoded-kbd-iso2022-invocations 2 2))
 210    ((= last-command-char ?\217)         ; SS3 (Single Shift 3)
 211     (aset encoded-kbd-iso2022-invocations 2 3))
 212    (t
 213   (let* ((charset (aref encoded-kbd-iso2022-designations
 214                         (or (aref encoded-kbd-iso2022-invocations 2)
 215                             (aref encoded-kbd-iso2022-invocations 1))))
 216          (char (if (= (charset-dimension charset) 1)
 217                    (make-char charset last-command-char)
 218                    (make-char charset last-command-char
 219                               (read-char-exclusive)))))
 220     (aset encoded-kbd-iso2022-invocations 2 nil)
 221       (setq unread-command-events (cons char unread-command-events))))))
 222
 223 (defun encoded-kbd-self-insert-sjis ()
 224   (interactive)
 225   (let ((char (if (or (< last-command-char ?\xA0) (>= last-command-char ?\xE0))
 226                   (decode-sjis-char (+ (ash last-command-char 8)
 227                                        (read-char-exclusive)))
 228                 (make-char 'katakana-jisx0201 last-command-char))))
 229     (setq unread-command-events (cons char unread-command-events))))
 230
 231 (defun encoded-kbd-self-insert-big5 ()
 232   (interactive)
 233   (let ((char (decode-big5-char (+ (ash last-command-char 8)
 234                                    (read-char-exclusive)))))
 235     (setq unread-command-events (cons char unread-command-events))))
 236
 237 (defun encoded-kbd-self-insert-ccl ()
 238   (interactive)
 239   (let ((str (char-to-string last-command-char))
 240         (coding (keyboard-coding-system)))
 241     (setq str (decode-coding-string str coding))
 242     (setq unread-command-events
 243           (append (string-to-list str) unread-command-events))))
 244
 245 (defun encoded-kbd-setup-keymap (coding)
 246   ;; At first, reset the keymap.
 247   (setcdr encoded-kbd-mode-map nil)
 248   ;; Then setup the keymap according to the keyboard coding system.
 249   (cond
 250    ((eq encoded-kbd-coding 'sjis)
 251     (let ((i 128))
 252       (while (< i 256)
 253         (define-key encoded-kbd-mode-map
 254           (vector i) 'encoded-kbd-self-insert-sjis)
 255         (setq i (1+ i)))))
 256
 257    ((eq encoded-kbd-coding 'big5)
 258     (let ((i 161))
 259       (while (< i 255)
 260         (define-key encoded-kbd-mode-map
 261           (vector i) 'encoded-kbd-self-insert-big5)
 262         (setq i (1+ i)))))
 263
 264    ((eq encoded-kbd-coding 'iso2022-7)
 265     (define-key encoded-kbd-mode-map "\e" 'encoded-kbd-iso2022-esc-prefix))
 266
 267    ((eq encoded-kbd-coding 'iso2022-8)
 268     (define-key encoded-kbd-mode-map
 269       (vector ?\216) 'encoded-kbd-self-insert-iso2022-8bit)
 270     (define-key encoded-kbd-mode-map
 271       (vector ?\217) 'encoded-kbd-self-insert-iso2022-8bit)
 272     (let ((i 160))
 273       (while (< i 256)
 274         (define-key encoded-kbd-mode-map
 275           (vector i) 'encoded-kbd-self-insert-iso2022-8bit)
 276         (setq i (1+ i)))))
 277
 278    ((eq encoded-kbd-coding 'ccl)
 279     (let ((valid-codes (or (coding-system-get coding 'valid-codes)
 280                            '((128 255))))
 281           elt from to)
 282       (while valid-codes
 283         (setq elt (car valid-codes) valid-codes (cdr valid-codes))
 284         (if (consp elt)
 285             (setq from (car elt) to (cdr elt))
 286           (setq from (setq to elt)))
 287         (while (<= from to)
 288           (if (>= from 128)
 289               (define-key encoded-kbd-mode-map
 290                 (vector from) 'encoded-kbd-self-insert-ccl))
 291           (setq from (1+ from))))))
 292
 293    (t
 294     (error "Invalid value in encoded-kbd-coding: %s" encoded-kbd-coding))))
 295
 296
 297 ;; Input mode at the time Encoded-kbd mode is turned on is saved here.
 298 (defvar saved-input-mode nil)
 299
 300 ;;;###autoload
 301 (defun encoded-kbd-mode (&optional arg)
 302   "Toggle Encoded-kbd minor mode.
 303 With arg, turn Encoded-kbd mode on if and only if arg is positive.
 304
 305 You should not turn this mode on manually, instead use the command
 306 \\[set-keyboard-coding-system] which turns on or off this mode
 307 automatically.
 308
 309 In Encoded-kbd mode, a text sent from keyboard is accepted
 310 as a multilingual text encoded in a coding system set by
 311 \\[set-keyboard-coding-system]."
 312   (if encoded-kbd-mode
 313       ;; We must at first reset input-mode to the original.
 314       (apply 'set-input-mode saved-input-mode))
 315   (setq encoded-kbd-mode
 316         (if (null arg) (null encoded-kbd-mode)
 317           (> (prefix-numeric-value arg) 0)))
 318   (if encoded-kbd-mode
 319       (let ((coding (keyboard-coding-system)))
 320         (setq saved-input-mode  (current-input-mode))
 321         (cond ((null coding)
 322                (setq encoded-kbd-mode nil)
 323                (error "No coding system for keyboard input is set"))
 324
 325               ((= (coding-system-type coding) 1) ; SJIS
 326                (set-input-mode
 327                 (nth 0 saved-input-mode) (nth 1 saved-input-mode)
 328                 'use-8th-bit (nth 3 saved-input-mode))
 329                (setq encoded-kbd-coding 'sjis))
 330
 331               ((= (coding-system-type coding) 2) ; ISO2022
 332                (if (aref (coding-system-flags coding) 7) ; 7-bit only
 333                    (setq encoded-kbd-coding 'iso2022-7)
 334                  (set-input-mode
 335                   (nth 0 saved-input-mode) (nth 1 saved-input-mode)
 336                   'use-8th-bit (nth 3 saved-input-mode))
 337                  (setq encoded-kbd-coding 'iso2022-8))
 338                (setq encoded-kbd-iso2022-designations (make-vector 4 nil))
 339                (let ((flags (coding-system-flags coding))
 340                      (i 0))
 341                  (while (< i 4)
 342                    (if (charsetp (aref flags i))
 343                        (aset encoded-kbd-iso2022-designations i
 344                              (aref flags i))
 345                      (if (charsetp (car-safe (aref flags i)))
 346                        (aset encoded-kbd-iso2022-designations i
 347                              (car (aref flags i)))))
 348                    (setq i (1+ i))))
 349                (setq encoded-kbd-iso2022-invocations (make-vector 3 nil))
 350                (aset encoded-kbd-iso2022-invocations 0 0)
 351                (aset encoded-kbd-iso2022-invocations 1 1))
 352
 353               ((= (coding-system-type coding) 3) ; BIG5
 354                (set-input-mode
 355                 (nth 0 saved-input-mode) (nth 1 saved-input-mode)
 356                 'use-8th-bit (nth 3 saved-input-mode))
 357                (setq encoded-kbd-coding 'big5))
 358
 359               ((= (coding-system-type coding) 4) ; CCL based coding
 360                (set-input-mode
 361                 (nth 0 saved-input-mode) (nth 1 saved-input-mode)
 362                 'use-8th-bit (nth 3 saved-input-mode))
 363                (setq encoded-kbd-coding 'ccl))
 364
 365               (t
 366                (setq encoded-kbd-mode nil)
 367                (error "Coding-system `%s' is not supported in Encoded-kbd mode"
 368                       (keyboard-coding-system))))
 369         (encoded-kbd-setup-keymap coding)
 370         (run-hooks 'encoded-kbd-mode-hook))))
 371
 372 ;;; encoded-kb.el ends here