1 ;;; mm-decode.el --- Functions for decoding MIME things
2 ;; Copyright (C) 1998,99 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)
47 (defmacro mm-handle-cache (handle)
49 (defmacro mm-handle-set-cache (handle contents)
50 `(setcar (nthcdr 6 ,handle) ,contents))
51 (defmacro mm-handle-id (handle)
53 (defmacro mm-make-handle (&optional buffer type encoding undisplayer
54 disposition description cache
56 `(list ,buffer ,type ,encoding ,undisplayer
57 ,disposition ,description ,cache ,id))
59 (defvar mm-inline-media-tests
60 '(("image/jpeg" mm-inline-image
61 (and window-system (featurep 'jpeg) (mm-image-fit-p handle)))
62 ("image/png" mm-inline-image
63 (and window-system (featurep 'png) (mm-image-fit-p handle)))
64 ("image/gif" mm-inline-image
65 (and window-system (featurep 'gif) (mm-image-fit-p handle)))
66 ("image/tiff" mm-inline-image
67 (and window-system (featurep 'tiff) (mm-image-fit-p handle)))
68 ("image/xbm" mm-inline-image
69 (and window-system (fboundp 'device-type)
70 (eq (device-type) 'x)))
71 ("image/x-xbitmap" mm-inline-image
72 (and window-system (fboundp 'device-type)
73 (eq (device-type) 'x)))
74 ("image/xpm" mm-inline-image
75 (and window-system (featurep 'xpm)))
76 ("image/x-pixmap" mm-inline-image
77 (and window-system (featurep 'xpm)))
78 ("image/bmp" mm-inline-image
79 (and window-system (featurep 'bmp)))
80 ("text/plain" mm-inline-text t)
81 ("text/enriched" mm-inline-text t)
82 ("text/richtext" mm-inline-text t)
83 ("text/html" mm-inline-text (locate-library "w3"))
84 ("text/x-vcard" mm-inline-text (locate-library "vcard"))
85 ("message/delivery-status" mm-inline-text t)
86 ("text/.*" mm-inline-text t)
87 ("audio/wav" mm-inline-audio
88 (and (or (featurep 'nas-sound) (featurep 'native-sound))
89 (device-sound-enabled-p)))
90 ("audio/au" mm-inline-audio
91 (and (or (featurep 'nas-sound) (featurep 'native-sound))
92 (device-sound-enabled-p)))
93 ("multipart/alternative" ignore t)
94 ("multipart/mixed" ignore t)
95 ("multipart/related" ignore t))
96 "Alist of media types/test that say whether the media types can be displayed inline.")
98 (defvar mm-user-display-methods
99 '(("image/.*" . inline)
101 ("message/delivery-status" . inline)))
103 (defvar mm-user-automatic-display
104 '("text/plain" "text/enriched" "text/richtext" "text/html"
105 "text/x-vcard" "image/.*" "message/delivery-status" "multipart/.*"))
107 (defvar mm-attachment-override-types
108 '("text/plain" "text/x-vcard")
109 "Types that should have \"attachment\" ignored if they can be displayed inline.")
111 (defvar mm-user-automatic-external-display nil
112 "List of MIME type regexps that will be displayed externally automatically.")
114 (defvar mm-alternative-precedence
115 '("multipart/related" "multipart/mixed" "multipart/alternative"
116 "image/jpeg" "image/gif" "text/html" "text/enriched"
117 "text/richtext" "text/plain")
118 "List that describes the precedence of alternative parts.")
120 (defvar mm-tmp-directory
121 (cond ((fboundp 'temp-directory) (temp-directory))
122 ((boundp 'temporary-file-directory) temporary-file-directory)
124 "Where mm will store its temporary files.")
126 (defvar mm-all-images-fit nil
127 "If non-nil, then all images fit in the buffer.")
129 ;;; Internal variables.
131 (defvar mm-dissection-list nil)
132 (defvar mm-last-shell-command "")
133 (defvar mm-content-id-alist nil)
137 (defun mm-dissect-buffer (&optional no-strict-mime)
138 "Dissect the current buffer and return a list of MIME handles."
140 (let (ct ctl type subtype cte cd description id result)
142 (mail-narrow-to-head)
143 (when (or no-strict-mime
144 (mail-fetch-field "mime-version"))
145 (setq ct (mail-fetch-field "content-type")
146 ctl (condition-case () (mail-header-parse-content-type ct)
148 cte (mail-fetch-field "content-transfer-encoding")
149 cd (mail-fetch-field "content-disposition")
150 description (mail-fetch-field "content-description")
151 id (mail-fetch-field "content-id"))))
153 (not (string-match "/" (car ctl))))
154 (mm-dissect-singlepart
155 '("text/plain") nil no-strict-mime
156 (and cd (condition-case ()
157 (mail-header-parse-content-disposition cd)
160 (setq type (split-string (car ctl) "/"))
161 (setq subtype (cadr type)
166 ((equal type "multipart")
167 (cons (car ctl) (mm-dissect-multipart ctl)))
169 (mm-dissect-singlepart
171 (and cte (intern (downcase (mail-header-remove-whitespace
172 (mail-header-remove-comments
175 (and cd (condition-case ()
176 (mail-header-parse-content-disposition cd)
180 (when (string-match " *<\\(.*\\)> *" id)
181 (setq id (match-string 1 id)))
182 (push (cons id result) mm-content-id-alist))
185 (defun mm-dissect-singlepart (ctl cte &optional force cdl description id)
187 (not (equal "text/plain" (car ctl))))
188 (let ((res (mm-make-handle
189 (mm-copy-to-buffer) ctl cte nil cdl description nil id)))
190 (push (car res) mm-dissection-list)
193 (defun mm-remove-all-parts ()
194 "Remove all MIME handles."
196 (mapcar 'mm-remove-part mm-dissection-list)
197 (setq mm-dissection-list nil))
199 (defun mm-dissect-multipart (ctl)
200 (goto-char (point-min))
201 (let* ((boundary (concat "\n--" (mail-content-type-get ctl 'boundary)))
202 (close-delimiter (concat (regexp-quote boundary) "--[ \t]*$"))
205 (goto-char (point-max))
206 (if (re-search-backward close-delimiter nil t)
209 (while (search-forward boundary end t)
210 (goto-char (match-beginning 0))
214 (narrow-to-region start (point))
215 (setq parts (nconc (list (mm-dissect-buffer t)) parts)))))
217 (setq start (point)))
221 (narrow-to-region start end)
222 (setq parts (nconc (list (mm-dissect-buffer t)) parts)))))
225 (defun mm-copy-to-buffer ()
226 "Copy the contents of the current buffer to a fresh buffer."
228 (let ((obuf (current-buffer))
230 (goto-char (point-min))
231 (search-forward-regexp "^\n" nil t)
233 (set-buffer (generate-new-buffer " *mm*"))
234 (insert-buffer-substring obuf beg)
237 (defun mm-inlinable-part-p (type)
238 "Say whether TYPE can be displayed inline."
239 (eq (mm-user-method type) 'inline))
241 (defun mm-display-part (handle &optional no-default)
242 "Display the MIME part represented by HANDLE.
243 Returns nil if the part is removed; inline if displayed inline;
244 external if displayed external."
246 (mailcap-parse-mailcaps)
247 (if (mm-handle-displayed-p handle)
248 (mm-remove-part handle)
249 (let* ((type (car (mm-handle-type handle)))
250 (method (mailcap-mime-info type))
251 (user-method (mm-user-method type)))
252 (if (eq user-method 'inline)
255 (mm-display-inline handle)
257 (when (or user-method
260 (if (and (not user-method)
262 (equal "text" (car (split-string type))))
265 (mm-insert-inline handle (mm-get-part handle))
268 handle (or user-method method
269 'mailcap-save-binary-file))
272 (defun mm-display-external (handle method)
273 "Display HANDLE using METHOD."
274 (mm-with-unibyte-buffer
275 (if (functionp method)
276 (let ((cur (current-buffer)))
277 (if (eq method 'mailcap-save-binary-file)
279 (set-buffer (generate-new-buffer "*mm*"))
281 (mm-insert-part handle)
282 (let ((win (get-buffer-window cur t)))
284 (select-window win)))
285 (switch-to-buffer (generate-new-buffer "*mm*")))
286 (buffer-disable-undo)
287 (mm-set-buffer-file-coding-system mm-binary-coding-system)
288 (insert-buffer-substring cur)
289 (message "Viewing with %s" method)
290 (let ((mm (current-buffer))
291 (non-viewer (assoc "non-viewer"
293 (car (mm-handle-type handle)) t))))
297 (mm-save-part handle))
298 (when (and (not non-viewer)
300 (mm-handle-set-undisplayer handle mm)))))
301 ;; The function is a string to be executed.
302 (mm-insert-part handle)
303 (let* ((dir (make-temp-name (expand-file-name "emm." mm-tmp-directory)))
304 (filename (mail-content-type-get
305 (mm-handle-disposition handle) 'filename))
306 (needsterm (assoc "needsterm"
308 (car (mm-handle-type handle)) t)))
310 ;; We create a private sub-directory where we store our files.
312 (set-file-modes dir 448)
314 (setq file (expand-file-name (file-name-nondirectory filename)
316 (setq file (make-temp-name (expand-file-name "mm." dir))))
317 (write-region (point-min) (point-max) file nil 'nomesg)
318 (message "Viewing with %s" method)
322 (start-process "*display*" nil
324 "-e" shell-file-name "-c"
326 (mm-quote-arg file)))
327 (start-process "*display*"
328 (setq buffer (generate-new-buffer "*mm*"))
331 (mm-quote-arg file)))))
332 (mm-handle-set-undisplayer handle (cons file buffer)))
333 (message "Displaying %s..." (format method file))))))
335 (defun mm-remove-parts (handles)
336 "Remove the displayed MIME parts represented by HANDLE."
337 (if (and (listp handles)
338 (bufferp (car handles)))
339 (mm-remove-part handles)
341 (while (setq handle (pop handles))
346 (stringp (car handle)))
347 (mm-remove-parts (cdr handle)))
349 (mm-remove-part handle)))))))
351 (defun mm-destroy-parts (handles)
352 "Remove the displayed MIME parts represented by HANDLE."
353 (if (and (listp handles)
354 (bufferp (car handles)))
355 (mm-destroy-part handles)
357 (while (setq handle (pop handles))
362 (stringp (car handle)))
363 (mm-destroy-parts (cdr handle)))
365 (mm-destroy-part handle)))))))
367 (defun mm-remove-part (handle)
368 "Remove the displayed MIME part represented by HANDLE."
370 (let ((object (mm-handle-undisplayer handle)))
373 ;; Internally displayed part.
374 ((mm-annotationp object)
375 (delete-annotation object))
376 ((or (functionp object)
378 (eq (car object) 'lambda)))
380 ;; Externally displayed part.
383 (delete-file (car object))
386 (delete-directory (file-name-directory (car object)))
389 (kill-buffer (cdr object))
392 (when (buffer-live-p object)
393 (kill-buffer object))))
395 (mm-handle-set-undisplayer handle nil))))
397 (defun mm-display-inline (handle)
398 (let* ((type (car (mm-handle-type handle)))
399 (function (cadr (assoc type mm-inline-media-tests))))
400 (funcall function handle)
401 (goto-char (point-min))))
403 (defun mm-inlinable-p (type)
404 "Say whether TYPE can be displayed inline."
405 (let ((alist mm-inline-media-tests)
408 (when (equal type (caar alist))
409 (setq test (caddar alist)
411 (setq test (eval test)))
415 (defun mm-user-method (type)
416 "Return the user-defined method for TYPE."
417 (let ((methods mm-user-display-methods)
419 (while (setq method (pop methods))
420 (when (string-match (car method) type)
421 (when (or (not (eq (cdr method) 'inline))
422 (mm-inlinable-p type))
423 (setq result (cdr method)
427 (defun mm-automatic-display-p (type)
428 "Return the user-defined method for TYPE."
429 (let ((methods mm-user-automatic-display)
431 (while (setq method (pop methods))
432 (when (and (string-match method type)
433 (mm-inlinable-p type))
438 (defun mm-attachment-override-p (type)
439 "Say whether TYPE should have attachment behavior overridden."
440 (let ((types mm-attachment-override-types)
443 (while (setq ty (pop types))
444 (when (and (string-match ty type)
445 (mm-inlinable-p type))
446 (throw 'found t))))))
448 (defun mm-automatic-external-display-p (type)
449 "Return the user-defined method for TYPE."
450 (let ((methods mm-user-automatic-external-display)
452 (while (setq method (pop methods))
453 (when (string-match method type)
458 (defun add-mime-display-method (type method)
459 "Make parts of TYPE be displayed with METHOD.
460 This overrides entries in the mailcap file."
461 (push (cons type method) mm-user-display-methods))
463 (defun mm-destroy-part (handle)
464 "Destroy the data structures connected to HANDLE."
466 (mm-remove-part handle)
467 (when (buffer-live-p (mm-handle-buffer handle))
468 (kill-buffer (mm-handle-buffer handle)))))
470 (defun mm-handle-displayed-p (handle)
471 "Say whether HANDLE is displayed or not."
472 (mm-handle-undisplayer handle))
474 (defun mm-quote-arg (arg)
475 "Return a version of ARG that is safe to evaluate in a shell."
476 (let ((pos 0) new-pos accum)
477 ;; *** bug: we don't handle newline characters properly
478 (while (setq new-pos (string-match "[;!`\"$\\& \t{} |()<>]" arg pos))
479 (push (substring arg pos new-pos) accum)
481 (push (list (aref arg new-pos)) accum)
482 (setq pos (1+ new-pos)))
485 (apply 'concat (nconc (nreverse accum) (list (substring arg pos)))))))
488 ;;; Functions for outputting parts
491 (defun mm-get-part (handle)
492 "Return the contents of HANDLE as a string."
493 (mm-with-unibyte-buffer
494 (mm-insert-part handle)
497 (defun mm-insert-part (handle)
498 "Insert the contents of HANDLE in the current buffer."
499 (let ((cur (current-buffer)))
501 (mm-with-unibyte-buffer
502 (insert-buffer-substring (mm-handle-buffer handle))
503 (mm-decode-content-transfer-encoding
504 (mm-handle-encoding handle)
505 (car (mm-handle-type handle)))
506 (let ((temp (current-buffer)))
508 (insert-buffer-substring temp))))))
510 (defvar mm-default-directory nil)
512 (defun mm-save-part (handle)
513 "Write HANDLE to a file."
514 (let* ((name (mail-content-type-get (mm-handle-type handle) 'name))
515 (filename (mail-content-type-get
516 (mm-handle-disposition handle) 'filename))
519 (setq filename (file-name-nondirectory filename)))
521 (read-file-name "Save MIME part to: "
523 (or filename name "")
524 (or mm-default-directory default-directory))))
525 (setq mm-default-directory (file-name-directory file))
526 (mm-with-unibyte-buffer
527 (mm-insert-part handle)
528 (when (or (not (file-exists-p file))
529 (yes-or-no-p (format "File %s already exists; overwrite? "
531 ;; Now every coding system is 100% binary within mm-with-unibyte-buffer
532 ;; Is text still special?
533 (let ((coding-system-for-write
534 (if (equal "text" (car (split-string
535 (car (mm-handle-type handle)) "/")))
536 buffer-file-coding-system
538 ;; Don't re-compress .gz & al. Arguably we should make
539 ;; `file-name-handler-alist' nil, but that would chop
540 ;; ange-ftp which it's reasonable to use here.
541 (inhibit-file-name-operation 'write-region)
542 (inhibit-file-name-handlers
543 (if (equal (car (mm-handle-type handle))
544 "application/octet-stream")
545 (cons 'jka-compr-handler inhibit-file-name-handlers)
546 inhibit-file-name-handlers)))
547 (write-region (point-min) (point-max) file))))))
549 (defun mm-pipe-part (handle)
550 "Pipe HANDLE to a process."
551 (let* ((name (mail-content-type-get (mm-handle-type handle) 'name))
553 (read-string "Shell command on MIME part: " mm-last-shell-command)))
554 (mm-with-unibyte-buffer
555 (mm-insert-part handle)
556 (shell-command-on-region (point-min) (point-max) command nil))))
558 (defun mm-interactively-view-part (handle)
559 "Display HANDLE using METHOD."
560 (let* ((type (car (mm-handle-type handle)))
562 (mapcar (lambda (i) (list (cdr (assoc 'viewer i))))
563 (mailcap-mime-info type 'all)))
564 (method (completing-read "Viewer: " methods)))
565 (mm-display-external (copy-sequence handle) method)))
567 (defun mm-preferred-alternative (handles &optional preferred)
568 "Say which of HANDLES are preferred."
569 (let ((prec (if preferred (list preferred) mm-alternative-precedence))
570 p h result type handle)
571 (while (setq p (pop prec))
575 (if (stringp (caar h))
577 (car (mm-handle-type (car h)))))
578 (setq handle (car h))
579 (when (and (equal p type)
580 (mm-automatic-display-p type)
581 (or (stringp (caar h))
582 (not (mm-handle-disposition (car h)))
583 (equal (car (mm-handle-disposition (car h)))
591 (defun mm-get-content-id (id)
592 "Return the handle(s) referred to by ID."
593 (cdr (assoc id mm-content-id-alist)))
595 (defun mm-get-image (handle)
596 "Return an image instance based on HANDLE."
597 (let ((type (cadr (split-string (car (mm-handle-type handle)) "/")))
599 ;; Allow some common translations.
602 ((equal type "x-pixmap")
604 ((equal type "x-xbitmap")
607 (or (mm-handle-cache handle)
608 (mm-with-unibyte-buffer
609 (mm-insert-part handle)
612 (make-glyph `[,(intern type) :data ,(buffer-string)]))
613 (mm-handle-set-cache handle spec))))))
615 (defun mm-image-fit-p (handle)
616 "Say whether the image in HANDLE will fit the current window."
617 (let ((image (mm-get-image handle)))
618 (or mm-all-images-fit
619 (and (< (glyph-width image) (window-pixel-width))
620 (< (glyph-height image) (window-pixel-height))))))
624 ;; mm-decode.el ends here