1 ;;; mm-decode.el --- Functions for decoding MIME things
2 ;; Copyright (C) 1998 Free Software Foundation, Inc.
4 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
5 ;; MORIOKA Tomohiko <morioka@jaist.ac.jp>
6 ;; This file is part of GNU Emacs.
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)
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.
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.
31 ;;; Convenience macros.
33 (defmacro mm-handle-buffer (handle)
35 (defmacro mm-handle-type (handle)
37 (defmacro mm-handle-encoding (handle)
39 (defmacro mm-handle-undisplayer (handle)
41 (defmacro mm-handle-set-undisplayer (handle function)
42 `(setcar (nthcdr 3 ,handle) ,function))
43 (defmacro mm-handle-disposition (handle)
45 (defmacro mm-handle-description (handle)
48 (defvar mm-inline-media-tests
49 '(("image/jpeg" mm-inline-image (featurep 'jpeg))
50 ("image/png" mm-inline-image (featurep 'png))
51 ("image/gif" mm-inline-image (featurep 'gif))
52 ("image/tiff" mm-inline-image (featurep 'tiff))
53 ("image/xbm" mm-inline-image (eq (device-type) 'x))
54 ("image/xpm" mm-inline-image (featurep 'xpm))
55 ("image/bmp" mm-inline-image (featurep 'bmp))
56 ("text/plain" mm-inline-text t)
57 ("text/enriched" mm-inline-text t)
58 ("text/richtext" mm-inline-text t)
59 ("text/html" mm-inline-text (featurep 'w3))
60 ("message/delivery-status" mm-inline-text t)
61 ("audio/wav" mm-inline-audio
62 (and (or (featurep 'nas-sound) (featurep 'native-sound))
63 (device-sound-enabled-p)))
64 ("audio/au" mm-inline-audio
65 (and (or (featurep 'nas-sound) (featurep 'native-sound))
66 (device-sound-enabled-p))))
67 "Alist of media types/test that say whether the media types can be displayed inline.")
69 (defvar mm-user-display-methods
70 '(("image/.*" . inline)
72 ("message/delivery-status" . inline)))
74 (defvar mm-user-automatic-display
75 '("text/plain" "text/enriched" "text/richtext" "text/html" "image/gif"
76 "message/delivery-status"))
78 (defvar mm-alternative-precedence
79 '("text/plain" "text/enriched" "text/richtext" "text/html")
80 "List that describes the precedence of alternative parts.")
82 (defvar mm-tmp-directory "/tmp/"
83 "Where mm will store its temporary files.")
85 ;;; Internal variables.
87 (defvar mm-dissection-list nil)
88 (defvar mm-last-shell-command "")
89 (defvar mm-content-id-alist nil)
93 (defun mm-dissect-buffer (&optional no-strict-mime)
94 "Dissect the current buffer and return a list of MIME handles."
96 (let (ct ctl type subtype cte cd description id result)
99 (when (and (or no-strict-mime
100 (mail-fetch-field "mime-version"))
101 (setq ct (mail-fetch-field "content-type")))
102 (setq ctl (condition-case () (mail-header-parse-content-type ct)
104 cte (mail-fetch-field "content-transfer-encoding")
105 cd (mail-fetch-field "content-disposition")
106 description (mail-fetch-field "content-description")
107 id (mail-fetch-field "content-id"))))
109 (mm-dissect-singlepart '("text/plain") nil no-strict-mime nil nil)
110 (setq type (split-string (car ctl) "/"))
111 (setq subtype (cadr type)
116 ((equal type "multipart")
117 (mm-dissect-multipart ctl))
119 (mm-dissect-singlepart
121 (and cte (intern (downcase (mail-header-remove-whitespace
122 (mail-header-remove-comments
125 (and cd (condition-case ()
126 (mail-header-parse-content-disposition cd)
129 (push (cons id result) mm-content-id-alist))
132 (defun mm-dissect-singlepart (ctl cte &optional force cdl description)
134 (not (equal "text/plain" (car ctl))))
135 (let ((res (list (list (mm-copy-to-buffer) ctl cte nil cdl description))))
136 (push (car res) mm-dissection-list)
139 (defun mm-remove-all-parts ()
140 "Remove all MIME handles."
142 (mapcar 'mm-remove-part mm-dissection-list)
143 (setq mm-dissection-list nil))
145 (defun mm-dissect-multipart (ctl)
146 (goto-char (point-min))
147 (let* ((boundary (concat "\n--" (mail-content-type-get ctl 'boundary)))
148 (close-delimiter (concat boundary "--[ \t]*$"))
151 (goto-char (point-max))
152 (if (re-search-backward close-delimiter nil t)
155 (while (search-forward boundary end t)
156 (goto-char (match-beginning 0))
160 (narrow-to-region start (point))
161 (setq parts (nconc (mm-dissect-buffer t) parts)))))
163 (setq start (point)))
167 (narrow-to-region start end)
168 (setq parts (nconc (mm-dissect-buffer t) parts)))))
171 (defun mm-copy-to-buffer ()
172 "Copy the contents of the current buffer to a fresh buffer."
174 (let ((obuf (current-buffer))
176 (goto-char (point-min))
177 (search-forward "\n\n" nil t)
179 (set-buffer (generate-new-buffer " *mm*"))
180 (insert-buffer-substring obuf beg)
183 (defun mm-inlinable-part-p (type)
184 "Say whether TYPE can be displayed inline."
185 (eq (mm-user-method type) 'inline))
187 (defun mm-display-part (handle &optional no-default)
188 "Display the MIME part represented by HANDLE."
190 (mailcap-parse-mailcaps)
191 (if (mm-handle-displayed-p handle)
192 (mm-remove-part handle)
193 (let* ((type (car (mm-handle-type handle)))
194 (method (mailcap-mime-info type))
195 (user-method (mm-user-method type)))
196 (if (eq user-method 'inline)
199 (mm-display-inline handle))
200 (when (or user-method
204 handle (or user-method method 'mailcap-save-binary-file))))))))
206 (defun mm-display-external (handle method)
207 "Display HANDLE using METHOD."
208 (mm-with-unibyte-buffer
209 (insert-buffer-substring (mm-handle-buffer handle))
210 (mm-decode-content-transfer-encoding
211 (mm-handle-encoding handle) (car (mm-handle-type handle)))
212 (if (functionp method)
213 (let ((cur (current-buffer)))
214 (if (eq method 'mailcap-save-binary-file)
215 (set-buffer (generate-new-buffer "*mm*"))
216 (select-window (get-buffer-window cur t))
217 (switch-to-buffer (generate-new-buffer "*mm*")))
218 (buffer-disable-undo)
219 (mm-set-buffer-file-coding-system 'no-conversion)
220 (insert-buffer-substring cur)
222 (mm-handle-set-undisplayer handle (current-buffer)))
223 (let* ((dir (make-temp-name (expand-file-name "emm." mm-tmp-directory)))
224 (filename (mail-content-type-get
225 (mm-handle-disposition handle) 'filename))
226 (needsterm (assoc "needsterm"
228 (car (mm-handle-type handle)) t)))
230 ;; We create a private sub-directory where we store our files.
232 (set-file-modes dir 448)
234 (setq file (expand-file-name (file-name-nondirectory filename)
236 (setq file (make-temp-name (expand-file-name "mm." dir))))
237 (write-region (point-min) (point-max)
238 file nil 'nomesg nil 'no-conversion)
241 (start-process "*display*" nil
243 "-e" shell-file-name "-c"
245 (mm-quote-arg file)))
246 (start-process "*display*" (generate-new-buffer "*mm*")
249 (mm-quote-arg file)))))
250 (mm-handle-set-undisplayer handle (cons file process))
251 (message "Displaying %s..." (format method file))))))
253 (defun mm-remove-part (handle)
254 "Remove the displayed MIME part represented by HANDLE."
255 (let ((object (mm-handle-undisplayer handle)))
258 ;; Internally displayed part.
259 ((mm-annotationp object)
260 (delete-annotation object))
261 ((or (functionp object)
263 (eq (car object) 'lambda)))
265 ;; Externally displayed part.
268 (delete-file (car object))
271 (delete-directory (file-name-directory (car object)))
274 (kill-process (cdr object))
277 (when (buffer-live-p object)
278 (kill-buffer object))))
280 (mm-handle-set-undisplayer handle nil)))
282 (defun mm-display-inline (handle)
283 (let* ((type (car (mm-handle-type handle)))
284 (function (cadr (assoc type mm-inline-media-tests))))
285 (funcall function handle)
286 (goto-char (point-min))))
288 (defun mm-inlinable-p (type)
289 "Say whether TYPE can be displayed inline."
290 (let ((alist mm-inline-media-tests)
293 (when (equal type (caar alist))
294 (setq test (caddar alist)
296 (setq test (eval test)))
300 (defun mm-user-method (type)
301 "Return the user-defined method for TYPE."
302 (let ((methods mm-user-display-methods)
304 (while (setq method (pop methods))
305 (when (string-match (car method) type)
306 (when (or (not (eq (cdr method) 'inline))
307 (mm-inlinable-p type))
308 (setq result (cdr method)
312 (defun mm-automatic-display-p (type)
313 "Return the user-defined method for TYPE."
314 (let ((methods mm-user-automatic-display)
316 (while (setq method (pop methods))
317 (when (string-match method type)
322 (defun add-mime-display-method (type method)
323 "Make parts of TYPE be displayed with METHOD.
324 This overrides entries in the mailcap file."
325 (push (cons type method) mm-user-display-methods))
327 (defun mm-destroy-part (handle)
328 "Destroy the data structures connected to HANDLE."
329 (mm-remove-part handle)
330 (when (buffer-live-p (mm-handle-buffer handle))
331 (kill-buffer (mm-handle-buffer handle))))
333 (defun mm-handle-displayed-p (handle)
334 "Say whether HANDLE is displayed or not."
335 (mm-handle-undisplayer handle))
337 (defun mm-quote-arg (arg)
338 "Return a version of ARG that is safe to evaluate in a shell."
339 (let ((pos 0) new-pos accum)
340 ;; *** bug: we don't handle newline characters properly
341 (while (setq new-pos (string-match "[!`\"$\\& \t{} ]" arg pos))
342 (push (substring arg pos new-pos) accum)
344 (push (list (aref arg new-pos)) accum)
345 (setq pos (1+ new-pos)))
348 (apply 'concat (nconc (nreverse accum) (list (substring arg pos)))))))
351 ;;; Functions for outputting parts
354 (defun mm-get-part (handle)
355 "Return the contents of HANDLE as a string."
356 (mm-with-unibyte-buffer
357 (insert-buffer-substring (mm-handle-buffer handle))
358 (mm-decode-content-transfer-encoding
359 (mm-handle-encoding handle)
360 (car (mm-handle-type handle)))
363 (defvar mm-default-directory nil)
365 (defun mm-save-part (handle)
366 "Write HANDLE to a file."
367 (let* ((name (mail-content-type-get (mm-handle-type handle) 'name))
368 (filename (mail-content-type-get
369 (mm-handle-disposition handle) 'filename))
372 (setq filename (file-name-nondirectory filename)))
374 (read-file-name "Save MIME part to: "
376 (or filename name "")
377 (or mm-default-directory default-directory))))
378 (setq mm-default-directory (file-name-directory file))
379 (mm-with-unibyte-buffer
380 (insert-buffer-substring (mm-handle-buffer handle))
381 (mm-decode-content-transfer-encoding
382 (mm-handle-encoding handle)
383 (car (mm-handle-type handle)))
384 (when (or (not (file-exists-p file))
385 (yes-or-no-p (format "File %s already exists; overwrite? "
387 (write-region (point-min) (point-max) file)))))
389 (defun mm-pipe-part (handle)
390 "Pipe HANDLE to a process."
391 (let* ((name (mail-content-type-get (mm-handle-type handle) 'name))
393 (read-string "Shell command on MIME part: " mm-last-shell-command)))
394 (mm-with-unibyte-buffer
395 (insert-buffer-substring (mm-handle-buffer handle))
396 (mm-decode-content-transfer-encoding
397 (mm-handle-encoding handle)
398 (car (mm-handle-type handle)))
399 (shell-command-on-region (point-min) (point-max) command nil))))
401 (defun mm-interactively-view-part (handle)
402 "Display HANDLE using METHOD."
403 (let* ((type (car (mm-handle-type handle)))
405 (mapcar (lambda (i) (list (cdr (assoc 'viewer i))))
406 (mailcap-mime-info type 'all)))
407 (method (completing-read "Viewer: " methods)))
408 (mm-display-external (copy-sequence handle) method)))
410 (defun mm-preferred-alternative (handles &optional preferred)
411 "Say which of HANDLES are preferred."
412 (let ((prec (if preferred (list preferred) mm-alternative-precedence))
414 (while (setq p (pop prec))
417 (setq type (car (mm-handle-type (car h))))
418 (when (and (equal p type)
419 (mm-automatic-display-p type)
420 (or (not (mm-handle-disposition (car h)))
421 (equal (car (mm-handle-disposition (car h)))
429 (defun mm-get-content-id (id)
430 "Return the handle(s) referred to by ID."
431 (cdr (assoc id mm-content-id-alist)))
435 ;; mm-decode.el ends here