1 ;;; tm-ew-d.el --- RFC 2047 based encoded-word decoder for GNU Emacs
3 ;; Copyright (C) 1995,1996 Free Software Foundation, Inc.
5 ;; Author: ENAMI Tsugutomo <enami@sys.ptg.sony.co.jp>
6 ;; MORIOKA Tomohiko <morioka@jaist.ac.jp>
7 ;; Maintainer: MORIOKA Tomohiko <morioka@jaist.ac.jp>
9 ;; Original: 1992/07/20 ENAMI Tsugutomo's `mime.el'.
10 ;; Renamed: 1993/06/03 to tiny-mime.el.
11 ;; Renamed: 1995/10/03 from tiny-mime.el. (split off encoder)
12 ;; Version: $Revision: 7.34 $
13 ;; Keywords: encoded-word, MIME, multilingual, header, mail, news
15 ;; This file is part of tm (Tools for MIME).
17 ;; This program is free software; you can redistribute it and/or
18 ;; modify it under the terms of the GNU General Public License as
19 ;; published by the Free Software Foundation; either version 2, or (at
20 ;; your option) any later version.
22 ;; This program is distributed in the hope that it will be useful, but
23 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
24 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25 ;; General Public License for more details.
27 ;; You should have received a copy of the GNU General Public License
28 ;; along with GNU Emacs; see the file COPYING. If not, write to the
29 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
30 ;; Boston, MA 02111-1307, USA.
43 (defconst tm-ew-d/RCS-ID
44 "$Id: tm-ew-d.el,v 7.34 1996/12/04 04:49:14 morioka Exp $")
45 (defconst mime/eword-decoder-version (get-version-string tm-ew-d/RCS-ID))
48 ;;; @ MIME encoded-word definition
51 (defconst mime/encoded-text-regexp "[!->@-~]+")
52 (defconst mime/encoded-word-regexp (concat (regexp-quote "=?")
60 mime/encoded-text-regexp
68 (defun mime-eword/decode-string (string &optional must-unfold)
69 "Decode MIME encoded-words in STRING.
71 STRING is unfolded before decoding.
73 If an encoded-word is broken or your emacs implementation can not
74 decode the charset included in it, it is not decoded.
76 If MUST-UNFOLD is non-nil, it unfolds and eliminates line-breaks even
77 if there are in decoded encoded-words (generated by bad manner MUA
78 such as a version of Net$cape). [tm-ew-d.el]"
79 (setq string (std11-unfold-string string))
80 (let ((dest "")(ew nil)
82 (while (and (string-match mime/encoded-word-regexp string)
83 (setq beg (match-beginning 0)
89 (string-match "^[ \t]+$" (substring string 0 beg))
91 (setq dest (concat dest (substring string 0 beg)))
96 (mime/decode-encoded-word
97 (substring string beg end) must-unfold)
99 (setq string (substring string end))
109 (defun mime-eword/decode-region (start end &optional unfolding must-unfold)
110 "Decode MIME encoded-words in region between START and END.
112 If UNFOLDING is not nil, it unfolds before decoding.
114 If MUST-UNFOLD is non-nil, it unfolds and eliminates line-breaks even
115 if there are in decoded encoded-words (generated by bad manner MUA
116 such as a version of Net$cape). [tm-ew-d.el]"
120 (narrow-to-region start end)
124 (goto-char (point-min))
125 (while (re-search-forward "\\?=\\(\n*\\s +\\)+=\\?" nil t)
126 (replace-match "?==?")
128 (goto-char (point-min))
129 (let (charset encoding text)
130 (while (re-search-forward mime/encoded-word-regexp nil t)
131 (insert (mime/decode-encoded-word
133 (buffer-substring (match-beginning 0) (match-end 0))
134 (delete-region (match-beginning 0) (match-end 0))
140 ;;; @ for message header
143 (defun mime/decode-message-header ()
144 "Decode MIME encoded-words in message header. [tm-ew-d.el]"
148 (narrow-to-region (goto-char (point-min))
149 (progn (re-search-forward "^$" nil t) (point)))
150 (mime-eword/decode-region (point-min) (point-max) t)
153 (defun mime/unfolding ()
154 (goto-char (point-min))
156 (while (re-search-forward std11-field-head-regexp nil t)
157 (setq beg (match-beginning 0)
158 end (std11-field-end))
159 (setq field (buffer-substring beg end))
160 (if (string-match mime/encoded-word-regexp field)
162 (narrow-to-region (goto-char beg) end)
163 (while (re-search-forward "\n\\([ \t]\\)" nil t)
167 (goto-char (point-max))
172 ;;; @ encoded-word decoder
175 (defun mime/decode-encoded-word (word &optional must-unfold)
176 "Decode WORD if it is an encoded-word.
178 If your emacs implementation can not decode the charset of WORD, it
179 returns WORD. Similarly the encoded-word is broken, it returns WORD.
181 If MUST-UNFOLD is non-nil, it unfolds and eliminates line-breaks even
182 if there are in decoded encoded-word (generated by bad manner MUA such
183 as a version of Net$cape). [tm-ew-d.el]"
184 (or (if (string-match mime/encoded-word-regexp word)
186 (substring word (match-beginning 1) (match-end 1))
190 (substring word (match-beginning 2) (match-end 2))
193 (substring word (match-beginning 3) (match-end 3))
196 (mime/decode-encoded-text charset encoding text must-unfold)
202 ;;; @ encoded-text decoder
205 (defun mime/decode-encoded-text (charset encoding string &optional must-unfold)
206 "Decode STRING as an encoded-text.
208 If your emacs implementation can not decode CHARSET, it returns nil.
210 If ENCODING is not \"B\" or \"Q\", it occurs error.
211 So you should write error-handling code if you don't want break by errors.
213 If MUST-UNFOLD is non-nil, it unfolds and eliminates line-breaks even
214 if there are in decoded encoded-text (generated by bad manner MUA such
215 as a version of Net$cape). [tm-ew-d.el]"
216 (let ((cs (mime-charset-to-coding-system charset)))
219 (cond ((and (string-equal "B" encoding)
220 (string-match mime/B-encoded-text-regexp string))
221 (base64-decode-string string))
222 ((and (string-equal "Q" encoding)
223 (string-match mime/Q-encoded-text-regexp string))
224 (q-encoding-decode-string string))
225 (t (message "Invalid encoded-word %s" encoding)
229 (setq dest (decode-coding-string dest cs))
238 (std11-unfold-string dest)
249 ;;; tm-ew-d.el ends here