code.delx.au - gnu-emacs/blob - share/emacs/site-lisp/w3m/w3m-ccl.el

   1 ;;; w3m-ccl.el --- CCL programs to process Unicode and internal characters.
   2
   3 ;; Copyright (C) 2001, 2003, 2004, 2005, 2006, 2007
   4 ;; TSUCHIYA Masatoshi <tsuchiya@namazu.org>
   5
   6 ;; Authors: TSUCHIYA Masatoshi <tsuchiya@namazu.org>,
   7 ;;          ARISAWA Akihiro <ari@mbf.sphere.ne.jp>
   8 ;; Keywords: w3m, WWW, hypermedia
   9
  10 ;; This file is a part of emacs-w3m.
  11
  12 ;; This program is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 2, or (at your option)
  15 ;; any later version.
  16
  17 ;; This program is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with this program; see the file COPYING.  If not, write to
  24 ;; the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  25 ;; Boston, MA 02110-1301, USA.
  26
  27 ;;; Commentary:
  28
  29 ;; This file contains CCL programs to process Unicode and internal
  30 ;; characters of w3m.  For more detail about emacs-w3m, see:
  31 ;;
  32 ;;    http://emacs-w3m.namazu.org/
  33
  34 ;;; MEMO:
  35
  36 ;; It is possible to support multi scripts without Mule-UCS.  For more
  37 ;; detail, see [emacs-w3m:01950]
  38
  39 ;;; Code:
  40
  41 (eval-and-compile
  42   (cond
  43    ((featurep 'xemacs)
  44     (require 'pccl))
  45    (t
  46     (require 'ccl))))
  47
  48 ;;; CCL programs:
  49
  50 (eval-when-compile
  51   (when (and (not (fboundp 'charset-id))
  52              (fboundp 'charset-id-internal))
  53     (defmacro charset-id (charset)
  54       "Return charset identification number of CHARSET."
  55       `(charset-id-internal ,charset))))
  56
  57 (eval-and-compile
  58   (defconst w3m-internal-characters-alist
  59     '((?\x90 . ? )                      ; ANSP (use for empty anchor)
  60       (?\x91 . ? )                      ; IMSP (blank around image)
  61       (?\xa0 . ? ))                     ; NBSP (non breakble space)
  62     "Alist of internal characters v.s. ASCII characters.")
  63
  64   (defun w3m-ccl-write-repeat (charset &optional r0 r1)
  65     (unless r0
  66       (setq r0 'r0))
  67     (unless r1
  68       (setq r1 (if (eq r0 'r1) 'r0 'r1)))
  69     (let ((unibyte (memq charset '(latin-iso8859-1 katakana-jisx0201))))
  70       (if (fboundp 'ccl-compile-write-multibyte-character)
  71           `((,r1 &= ?\x7f)
  72             ,@(unless unibyte
  73                 `((,r1 |= ((,r0 & ?\x7f) << 7))))
  74             (,r0 = ,(charset-id charset))
  75             (write-multibyte-character ,r0 ,r1)
  76             (repeat))
  77         `((write ,(charset-id charset))
  78           ,@(unless unibyte
  79               `((write ,r0)))
  80           (write-repeat ,r1)))))
  81
  82   (defconst w3m-ccl-write-euc-japan-character
  83     (when (fboundp 'ccl-compile-read-multibyte-character)
  84       `((read-multibyte-character r1 r0)
  85         (if (r1 == ,(charset-id 'ascii))
  86             ;; (1) ASCII characters
  87             (write-repeat r0))
  88         (if (r1 == ,(charset-id 'latin-jisx0201))
  89             ;; (2) Latin Part of Japanese JISX0201.1976
  90             ;;     Convert to ASCII
  91             (write-repeat r0))
  92         (r2 = (r1 == ,(charset-id 'japanese-jisx0208-1978)))
  93         (if ((r1 == ,(charset-id 'japanese-jisx0208)) | r2)
  94             ;; (3) Characters of Japanese JISX0208.
  95             ((r1 = ((r0 & 127) | 128))
  96              (r0 = ((r0 >> 7) | 128))
  97              (write r0)
  98              (write-repeat r1)))
  99         (if (r1 == ,(charset-id 'katakana-jisx0201))
 100             ;; (4) Katakana Part of Japanese JISX0201.1976
 101             ((r0 |= 128)
 102              (write ?\x8e)
 103              (write-repeat r0)))))
 104     "CCL program to write characters represented in `euc-japan'.")
 105
 106   (defconst w3m-ccl-write-iso-latin-1-character
 107     (when (fboundp 'ccl-compile-read-multibyte-character)
 108       `((read-multibyte-character r1 r0)
 109         (if (r1 == ,(charset-id 'ascii))
 110             ;; (1) ASCII characters
 111             (write-repeat r0))
 112         (if (r1 == ,(charset-id 'latin-jisx0201))
 113             ;; (2) Latin Part of Japanese JISX0201.1976
 114             ;;     Convert to ASCII
 115             (write-repeat r0))
 116         (if (r1 == ,(charset-id 'latin-iso8859-1))
 117             ;; (3) Latin-1 characters
 118             ((r0 |= ?\x80)
 119              (write-repeat r0)))))
 120     "CCL program to write characters represented in `iso-latin-1'.")
 121
 122   (defconst w3m-ccl-generate-ncr
 123     `((r1 = 0)
 124       (r2 = 0)
 125       (loop
 126        (r1 = (r1 << 4))
 127        (r1 |= (r0 & 15))
 128        (r0 = (r0 >> 4))
 129        (if (r0 == 0)
 130            (break)
 131          ((r2 += 1)
 132           (repeat))))
 133       (write "&#x")
 134       (loop
 135        (branch (r1 & 15)
 136                ,@(mapcar
 137                   (lambda (i)
 138                     (list 'write (string-to-char (format "%x" i))))
 139                   '(0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15)))
 140        (r1 = (r1 >> 4))
 141        (if (r2 == 0)
 142            ((write ?\;)
 143             (break))
 144          ((r2 -= 1)
 145           (repeat))))
 146       (repeat))
 147     "CCL program to generate a string which represents a UCS codepoint
 148 in NCR (Numeric Character References)."))
 149
 150 (define-ccl-program w3m-euc-japan-decoder
 151   `(2
 152     (loop
 153      (read r0)
 154      ;; Process normal EUC characters.
 155      (if (r0 < ?\x80)
 156          (write-repeat r0))
 157      (if (r0 > ?\xa0)
 158          ((read r1)
 159           ,@(w3m-ccl-write-repeat 'japanese-jisx0208)))
 160      (if (r0 == ?\x8e)
 161          ((read r1)
 162           ,@(w3m-ccl-write-repeat 'katakana-jisx0201)))
 163      (if (r0 == ?\x8f)
 164          ((read r0)
 165           (read r1)
 166           ,@(w3m-ccl-write-repeat 'japanese-jisx0212)))
 167      ;; Process internal characters used in w3m.
 168      ,@(mapcar (lambda (pair)
 169                  `(if (r0 == ,(car pair))
 170                       (write-repeat ,(cdr pair))))
 171                w3m-internal-characters-alist)
 172      (write-repeat r0))))
 173
 174 (unless (get 'w3m-euc-japan-encoder 'ccl-program-idx)
 175   (define-ccl-program w3m-euc-japan-encoder
 176     `(1 (loop (read r0) (write-repeat r0)))))
 177
 178 (define-ccl-program w3m-iso-latin-1-decoder
 179   `(2
 180     (loop
 181      (read r0)
 182      ;; Process ASCII characters.
 183      (if (r0 < ?\x80)
 184          (write-repeat r0))
 185      ;; Process Latin-1 characters.
 186      (if (r0 > ?\xa0)
 187          (,@(w3m-ccl-write-repeat 'latin-iso8859-1 'r1)))
 188      ;; Process internal characters used in w3m.
 189      ,@(mapcar (lambda (pair)
 190                  `(if (r0 == ,(car pair))
 191                       (write-repeat ,(cdr pair))))
 192                w3m-internal-characters-alist)
 193      (write-repeat r0))))
 194
 195 (unless (get 'w3m-iso-latin-1-encoder 'ccl-program-idx)
 196   (define-ccl-program w3m-iso-latin-1-encoder
 197     `(1 (loop (read r0) (write-repeat r0)))))
 198
 199
 200 (provide 'w3m-ccl)
 201
 202 ;;; w3m-ccl.el ends here