1 ;;; mel.el : a MIME encoding/decoding library
3 ;; Copyright (C) 1995,1996,1997,1998 Free Software Foundation, Inc.
5 ;; Author: MORIOKA Tomohiko <morioka@jaist.ac.jp>
7 ;; Keywords: MIME, Base64, Quoted-Printable, uuencode, gzip64
9 ;; This file is part of FLIM (Faithful Library about Internet Message).
11 ;; This program is free software; you can redistribute it and/or
12 ;; modify it under the terms of the GNU General Public License as
13 ;; published by the Free Software Foundation; either version 2, or (at
14 ;; your option) any later version.
16 ;; This program is distributed in the hope that it will be useful, but
17 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 ;; General Public License for more details.
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 the
23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24 ;; Boston, MA 02111-1307, USA.
31 (defcustom mime-encoding-list
32 '("7bit" "8bit" "binary" "base64" "quoted-printable")
33 "List of Content-Transfer-Encoding. Each encoding must be string."
35 :type '(repeat string))
37 (defun mime-encoding-list (&optional service)
38 "Return list of Content-Transfer-Encoding.
39 If SERVICE is specified, it returns available list of
40 Content-Transfer-Encoding for it."
43 (mapatoms (lambda (sym)
45 (setq dest (cons (symbol-name sym) dest)))
47 (symbol-value (intern (format "%s-obarray" service))))
48 (let ((rest mel-encoding-module-alist)
50 (while (setq pair (car rest))
51 (let ((key (car pair)))
54 (setq dest (cons key dest))))
55 (setq rest (cdr rest)))
60 (defun mime-encoding-alist (&optional service)
61 "Return table of Content-Transfer-Encoding for completion."
62 (mapcar #'list (mime-encoding-list service))
65 (defsubst mel-use-module (name encodings)
67 (while (setq encoding (car encodings))
68 (set-alist 'mel-encoding-module-alist
70 (cons name (cdr (assoc encoding mel-encoding-module-alist))))
71 (setq encodings (cdr encodings))
74 (defsubst mel-find-function (service encoding)
75 (mel-find-function-from-obarray
76 (symbol-value (intern (format "%s-obarray" service))) encoding))
79 ;;; @ setting for modules
82 (mel-define-backend "7bit")
83 (mel-define-method-function (mime-encode-string string (nil "7bit"))
85 (mel-define-method-function (mime-decode-string string (nil "7bit"))
87 (mel-define-method mime-encode-region (start end (nil "7bit")))
88 (mel-define-method mime-decode-region (start end (nil "7bit")))
89 (mel-define-method-function (mime-insert-encoded-file filename (nil "7bit"))
90 'insert-file-contents-as-binary)
91 (mel-define-method-function (mime-write-decoded-region
92 start end filename (nil "7bit"))
93 'write-region-as-binary)
95 (mel-define-backend "8bit" ("7bit"))
97 (mel-define-backend "binary" ("8bit"))
99 (when (and (fboundp 'base64-encode-string)
100 (subrp (symbol-function 'base64-encode-string)))
101 (mel-define-backend "base64")
102 (mel-define-method-function (mime-encode-string string (nil "base64"))
103 'base64-encode-string)
104 (mel-define-method-function (mime-decode-string string (nil "base64"))
105 'base64-decode-string)
106 (mel-define-method-function (mime-encode-region start end (nil "base64"))
107 'base64-encode-region)
108 (mel-define-method-function (mime-decode-region start end (nil "base64"))
109 'base64-decode-region)
110 (mel-define-method mime-insert-encoded-file (filename (nil "base64"))
111 "Encode contents of file FILENAME to base64, and insert the result.
112 It calls external base64 encoder specified by
113 `base64-external-encoder'. So you must install the program (maybe
114 mmencode included in metamail or XEmacs package)."
115 (interactive (list (read-file-name "Insert encoded file: ")))
116 (insert (base64-encode-string
118 (set-buffer-multibyte nil)
119 (insert-file-contents-as-binary filename)
125 (mel-define-method-function (encoded-text-encode-string string (nil "B"))
126 'base64-encode-string)
127 (mel-define-method encoded-text-decode-string (string (nil "B"))
128 (if (and (string-match B-encoded-text-regexp string)
129 (string= string (match-string 0 string)))
130 (base64-decode-string string)
131 (error "Invalid encoded-text %s" string)))
134 (mel-use-module 'mel-b-el '("base64" "B"))
135 (mel-use-module 'mel-q '("quoted-printable" "Q"))
136 (mel-use-module 'mel-g '("x-gzip64"))
137 (mel-use-module 'mel-u '("x-uue" "x-uuencode"))
139 (defvar mel-b-ccl-module
140 (and (featurep 'mule)
143 (module-installed-p 'mel-b-ccl)
146 (defvar mel-q-ccl-module
147 (and (featurep 'mule)
150 (module-installed-p 'mel-q-ccl)
154 (mel-use-module 'mel-b-ccl '("base64" "B"))
158 (mel-use-module 'mel-q-ccl '("quoted-printable" "Q"))
162 (mel-use-module 'mel-b-dl '("base64" "B"))
170 (defun mime-encode-region (start end encoding)
171 "Encode region START to END of current buffer using ENCODING.
172 ENCODING must be string."
174 (list (region-beginning) (region-end)
175 (completing-read "encoding: "
176 (mime-encoding-alist)
178 (funcall (mel-find-function 'mime-encode-region encoding) start end)
183 (defun mime-decode-region (start end encoding)
184 "Decode region START to END of current buffer using ENCODING.
185 ENCODING must be string."
187 (list (region-beginning) (region-end)
188 (completing-read "encoding: "
189 (mime-encoding-alist 'mime-decode-region)
191 (funcall (mel-find-function 'mime-decode-region encoding)
199 (defun mime-decode-string (string encoding)
200 "Decode STRING using ENCODING.
201 ENCODING must be string. If ENCODING is found in
202 `mime-string-decoding-method-alist' as its key, this function decodes
203 the STRING by its value."
204 (funcall (mel-find-function 'mime-decode-string encoding)
208 (mel-define-service encoded-text-encode-string (string encoding)
209 "Encode STRING as encoded-text using ENCODING.
210 ENCODING must be string.")
212 (mel-define-service encoded-text-decode-string (string encoding)
213 "Decode STRING as encoded-text using ENCODING.
214 ENCODING must be string.")
216 (defun base64-encoded-length (string)
217 (* (/ (+ (length string) 2) 3) 4))
219 (defsubst Q-encoding-printable-char-p (chr mode)
220 (and (not (memq chr '(?= ?? ?_)))
221 (<= ?\ chr)(<= chr ?~)
222 (cond ((eq mode 'text) t)
224 (not (memq chr '(?\( ?\) ?\\)))
227 (string-match "[A-Za-z0-9!*+/=_---]" (char-to-string chr))
230 (defun Q-encoded-text-length (string &optional mode)
231 (let ((l 0)(i 0)(len (length string)) chr)
233 (setq chr (elt string i))
234 (if (Q-encoding-printable-char-p chr mode)
246 (defun mime-insert-encoded-file (filename encoding)
247 "Insert file FILENAME encoded by ENCODING format."
249 (list (read-file-name "Insert encoded file: ")
250 (completing-read "encoding: "
251 (mime-encoding-alist)
253 (funcall (mel-find-function 'mime-insert-encoded-file encoding)
258 (defun mime-write-decoded-region (start end filename encoding)
259 "Decode and write current region encoded by ENCODING into FILENAME.
260 START and END are buffer positions."
262 (list (region-beginning) (region-end)
263 (read-file-name "Write decoded region to file: ")
264 (completing-read "encoding: "
265 (mime-encoding-alist 'mime-write-decoded-region)
267 (funcall (mel-find-function 'mime-write-decoded-region encoding)
276 ;;; mel.el ends here.