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