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 ("message/delivery-status" mm-inline-text t)
85 ("text/.*" mm-inline-text t)
86 ("audio/wav" mm-inline-audio
87 (and (or (featurep 'nas-sound) (featurep 'native-sound))
88 (device-sound-enabled-p)))
89 ("audio/au" mm-inline-audio
90 (and (or (featurep 'nas-sound) (featurep 'native-sound))
91 (device-sound-enabled-p)))
92 ("multipart/alternative" ignore t)
93 ("multipart/mixed" ignore t)
94 ("multipart/related" ignore t))
95 "Alist of media types/test that say whether the media types can be displayed inline.")
97 (defvar mm-user-display-methods
98 '(("image/.*" . inline)
100 ("message/delivery-status" . inline)))
102 (defvar mm-user-automatic-display
103 '("text/plain" "text/enriched" "text/richtext" "text/html"
104 "image/.*" "message/delivery-status" "multipart/.*"))
106 (defvar mm-user-automatic-external-display nil
107 "List of MIME type regexps that will be displayed externally automatically.")
109 (defvar mm-alternative-precedence
110 '("multipart/related" "multipart/mixed" "multipart/alternative"
111 "image/jpeg" "image/gif" "text/html" "text/enriched"
112 "text/richtext" "text/plain")
113 "List that describes the precedence of alternative parts.")
115 (defvar mm-tmp-directory
116 (cond ((fboundp 'temp-directory) (temp-directory))
117 ((boundp 'temporary-file-directory) temporary-file-directory)
119 "Where mm will store its temporary files.")
121 (defvar mm-all-images-fit nil
122 "If non-nil, then all images fit in the buffer.")
124 ;;; Internal variables.
126 (defvar mm-dissection-list nil)
127 (defvar mm-last-shell-command "")
128 (defvar mm-content-id-alist nil)
132 (defun mm-dissect-buffer (&optional no-strict-mime)
133 "Dissect the current buffer and return a list of MIME handles."
135 (let (ct ctl type subtype cte cd description id result)
137 (mail-narrow-to-head)
138 (when (or no-strict-mime
139 (mail-fetch-field "mime-version"))
140 (setq ct (mail-fetch-field "content-type")
141 ctl (condition-case () (mail-header-parse-content-type ct)
143 cte (mail-fetch-field "content-transfer-encoding")
144 cd (mail-fetch-field "content-disposition")
145 description (mail-fetch-field "content-description")
146 id (mail-fetch-field "content-id"))))
148 (not (string-match "/" (car ctl))))
149 (mm-dissect-singlepart
150 '("text/plain") nil no-strict-mime
151 (and cd (condition-case ()
152 (mail-header-parse-content-disposition cd)
155 (setq type (split-string (car ctl) "/"))
156 (setq subtype (cadr type)
161 ((equal type "multipart")
162 (cons (car ctl) (mm-dissect-multipart ctl)))
164 (mm-dissect-singlepart
166 (and cte (intern (downcase (mail-header-remove-whitespace
167 (mail-header-remove-comments
170 (and cd (condition-case ()
171 (mail-header-parse-content-disposition cd)
175 (when (string-match " *<\\(.*\\)> *" id)
176 (setq id (match-string 1 id)))
177 (push (cons id result) mm-content-id-alist))
180 (defun mm-dissect-singlepart (ctl cte &optional force cdl description id)
182 (not (equal "text/plain" (car ctl))))
183 (let ((res (mm-make-handle
184 (mm-copy-to-buffer) ctl cte nil cdl description nil id)))
185 (push (car res) mm-dissection-list)
188 (defun mm-remove-all-parts ()
189 "Remove all MIME handles."
191 (mapcar 'mm-remove-part mm-dissection-list)
192 (setq mm-dissection-list nil))
194 (defun mm-dissect-multipart (ctl)
195 (goto-char (point-min))
196 (let* ((boundary (concat "\n--" (mail-content-type-get ctl 'boundary)))
197 (close-delimiter (concat (regexp-quote boundary) "--[ \t]*$"))
200 (goto-char (point-max))
201 (if (re-search-backward close-delimiter nil t)
204 (while (search-forward boundary end t)
205 (goto-char (match-beginning 0))
209 (narrow-to-region start (point))
210 (setq parts (nconc (list (mm-dissect-buffer t)) parts)))))
212 (setq start (point)))
216 (narrow-to-region start end)
217 (setq parts (nconc (list (mm-dissect-buffer t)) parts)))))
220 (defun mm-copy-to-buffer ()
221 "Copy the contents of the current buffer to a fresh buffer."
223 (let ((obuf (current-buffer))
225 (goto-char (point-min))
226 (search-forward-regexp "^\n" nil t)
228 (set-buffer (generate-new-buffer " *mm*"))
229 (insert-buffer-substring obuf beg)
232 (defun mm-inlinable-part-p (type)
233 "Say whether TYPE can be displayed inline."
234 (eq (mm-user-method type) 'inline))
236 (defun mm-display-part (handle &optional no-default)
237 "Display the MIME part represented by HANDLE.
238 Returns nil if the part is removed; inline if displayed inline;
239 external if displayed external."
241 (mailcap-parse-mailcaps)
242 (if (mm-handle-displayed-p handle)
243 (mm-remove-part handle)
244 (let* ((type (car (mm-handle-type handle)))
245 (method (mailcap-mime-info type))
246 (user-method (mm-user-method type)))
247 (if (eq user-method 'inline)
250 (mm-display-inline handle)
252 (when (or user-method
255 (if (and (not user-method)
257 (equal "text" (car (split-string type))))
260 (mm-insert-inline handle (mm-get-part handle))
263 handle (or user-method method
264 'mailcap-save-binary-file))
267 (defun mm-display-external (handle method)
268 "Display HANDLE using METHOD."
269 (mm-with-unibyte-buffer
270 (if (functionp method)
271 (let ((cur (current-buffer)))
272 (if (eq method 'mailcap-save-binary-file)
274 (set-buffer (generate-new-buffer "*mm*"))
276 (mm-insert-part handle)
277 (let ((win (get-buffer-window cur t)))
279 (select-window win)))
280 (switch-to-buffer (generate-new-buffer "*mm*")))
281 (buffer-disable-undo)
282 (mm-set-buffer-file-coding-system mm-binary-coding-system)
283 (insert-buffer-substring cur)
284 (message "Viewing with %s" method)
285 (let ((mm (current-buffer))
286 (non-viewer (assoc "non-viewer"
288 (car (mm-handle-type handle)) t))))
292 (mm-save-part handle))
294 (mm-handle-set-undisplayer handle mm)))))
295 ;; The function is a string to be executed.
296 (mm-insert-part handle)
297 (let* ((dir (make-temp-name (expand-file-name "emm." mm-tmp-directory)))
298 (filename (mail-content-type-get
299 (mm-handle-disposition handle) 'filename))
300 (needsterm (assoc "needsterm"
302 (car (mm-handle-type handle)) t)))
304 ;; We create a private sub-directory where we store our files.
306 (set-file-modes dir 448)
308 (setq file (expand-file-name (file-name-nondirectory filename)
310 (setq file (make-temp-name (expand-file-name "mm." dir))))
311 (write-region (point-min) (point-max) file nil 'nomesg)
312 (message "Viewing with %s" method)
316 (start-process "*display*" nil
318 "-e" shell-file-name "-c"
320 (mm-quote-arg file)))
321 (start-process "*display*"
322 (setq buffer (generate-new-buffer "*mm*"))
325 (mm-quote-arg file)))))
326 (mm-handle-set-undisplayer handle (cons file buffer)))
327 (message "Displaying %s..." (format method file))))))
329 (defun mm-remove-parts (handles)
330 "Remove the displayed MIME parts represented by HANDLE."
331 (if (and (listp handles)
332 (bufferp (car handles)))
333 (mm-remove-part handles)
335 (while (setq handle (pop handles))
340 (stringp (car handle)))
341 (mm-remove-parts (cdr handle)))
343 (mm-remove-part handle)))))))
345 (defun mm-destroy-parts (handles)
346 "Remove the displayed MIME parts represented by HANDLE."
347 (if (and (listp handles)
348 (bufferp (car handles)))
349 (mm-destroy-part handles)
351 (while (setq handle (pop handles))
356 (stringp (car handle)))
357 (mm-destroy-parts (cdr handle)))
359 (mm-destroy-part handle)))))))
361 (defun mm-remove-part (handle)
362 "Remove the displayed MIME part represented by HANDLE."
364 (let ((object (mm-handle-undisplayer handle)))
367 ;; Internally displayed part.
368 ((mm-annotationp object)
369 (delete-annotation object))
370 ((or (functionp object)
372 (eq (car object) 'lambda)))
374 ;; Externally displayed part.
377 (delete-file (car object))
380 (delete-directory (file-name-directory (car object)))
383 (kill-buffer (cdr object))
386 (when (buffer-live-p object)
387 (kill-buffer object))))
389 (mm-handle-set-undisplayer handle nil))))
391 (defun mm-display-inline (handle)
392 (let* ((type (car (mm-handle-type handle)))
393 (function (cadr (assoc type mm-inline-media-tests))))
394 (funcall function handle)
395 (goto-char (point-min))))
397 (defun mm-inlinable-p (type)
398 "Say whether TYPE can be displayed inline."
399 (let ((alist mm-inline-media-tests)
402 (when (equal type (caar alist))
403 (setq test (caddar alist)
405 (setq test (eval test)))
409 (defun mm-user-method (type)
410 "Return the user-defined method for TYPE."
411 (let ((methods mm-user-display-methods)
413 (while (setq method (pop methods))
414 (when (string-match (car method) type)
415 (when (or (not (eq (cdr method) 'inline))
416 (mm-inlinable-p type))
417 (setq result (cdr method)
421 (defun mm-automatic-display-p (type)
422 "Return the user-defined method for TYPE."
423 (let ((methods mm-user-automatic-display)
425 (while (setq method (pop methods))
426 (when (and (string-match method type)
427 (mm-inlinable-p type))
432 (defun mm-automatic-external-display-p (type)
433 "Return the user-defined method for TYPE."
434 (let ((methods mm-user-automatic-external-display)
436 (while (setq method (pop methods))
437 (when (string-match method type)
442 (defun add-mime-display-method (type method)
443 "Make parts of TYPE be displayed with METHOD.
444 This overrides entries in the mailcap file."
445 (push (cons type method) mm-user-display-methods))
447 (defun mm-destroy-part (handle)
448 "Destroy the data structures connected to HANDLE."
450 (mm-remove-part handle)
451 (when (buffer-live-p (mm-handle-buffer handle))
452 (kill-buffer (mm-handle-buffer handle)))))
454 (defun mm-handle-displayed-p (handle)
455 "Say whether HANDLE is displayed or not."
456 (mm-handle-undisplayer handle))
458 (defun mm-quote-arg (arg)
459 "Return a version of ARG that is safe to evaluate in a shell."
460 (let ((pos 0) new-pos accum)
461 ;; *** bug: we don't handle newline characters properly
462 (while (setq new-pos (string-match "[;!`\"$\\& \t{} |()<>]" arg pos))
463 (push (substring arg pos new-pos) accum)
465 (push (list (aref arg new-pos)) accum)
466 (setq pos (1+ new-pos)))
469 (apply 'concat (nconc (nreverse accum) (list (substring arg pos)))))))
472 ;;; Functions for outputting parts
475 (defun mm-get-part (handle)
476 "Return the contents of HANDLE as a string."
477 (mm-with-unibyte-buffer
478 (mm-insert-part handle)
481 (defun mm-insert-part (handle)
482 "Insert the contents of HANDLE in the current buffer."
483 (let ((cur (current-buffer)))
485 (mm-with-unibyte-buffer
486 (insert-buffer-substring (mm-handle-buffer handle))
487 (mm-decode-content-transfer-encoding
488 (mm-handle-encoding handle)
489 (car (mm-handle-type handle)))
490 (let ((temp (current-buffer)))
492 (insert-buffer temp))))))
494 (defvar mm-default-directory nil)
496 (defun mm-save-part (handle)
497 "Write HANDLE to a file."
498 (let* ((name (mail-content-type-get (mm-handle-type handle) 'name))
499 (filename (mail-content-type-get
500 (mm-handle-disposition handle) 'filename))
503 (setq filename (file-name-nondirectory filename)))
505 (read-file-name "Save MIME part to: "
507 (or filename name "")
508 (or mm-default-directory default-directory))))
509 (setq mm-default-directory (file-name-directory file))
510 (mm-with-unibyte-buffer
511 (mm-insert-part handle)
512 (when (or (not (file-exists-p file))
513 (yes-or-no-p (format "File %s already exists; overwrite? "
515 ;; Now every coding system is 100% binary within mm-with-unibyte-buffer
516 ;; Is text still special?
517 (let ((coding-system-for-write
518 (if (equal "text" (car (split-string
519 (car (mm-handle-type handle)) "/")))
520 buffer-file-coding-system
522 ;; Don't re-compress .gz & al. Arguably we should make
523 ;; `file-name-handler-alist' nil, but that would chop
524 ;; ange-ftp which it's reasonable to use here.
525 (inhibit-file-name-operation 'write-region)
526 (inhibit-file-name-handlers
527 (if (equal (car (mm-handle-type handle))
528 "application/octet-stream")
529 (cons 'jka-compr-handler inhibit-file-name-handlers)
530 inhibit-file-name-handlers)))
531 (write-region (point-min) (point-max) file))))))
533 (defun mm-pipe-part (handle)
534 "Pipe HANDLE to a process."
535 (let* ((name (mail-content-type-get (mm-handle-type handle) 'name))
537 (read-string "Shell command on MIME part: " mm-last-shell-command)))
538 (mm-with-unibyte-buffer
539 (mm-insert-part handle)
540 (shell-command-on-region (point-min) (point-max) command nil))))
542 (defun mm-interactively-view-part (handle)
543 "Display HANDLE using METHOD."
544 (let* ((type (car (mm-handle-type handle)))
546 (mapcar (lambda (i) (list (cdr (assoc 'viewer i))))
547 (mailcap-mime-info type 'all)))
548 (method (completing-read "Viewer: " methods)))
549 (mm-display-external (copy-sequence handle) method)))
551 (defun mm-preferred-alternative (handles &optional preferred)
552 "Say which of HANDLES are preferred."
553 (let ((prec (if preferred (list preferred) mm-alternative-precedence))
554 p h result type handle)
555 (while (setq p (pop prec))
559 (if (stringp (caar h))
561 (car (mm-handle-type (car h)))))
562 (setq handle (car h))
563 (when (and (equal p type)
564 (mm-automatic-display-p type)
565 (or (stringp (caar h))
566 (not (mm-handle-disposition (car h)))
567 (equal (car (mm-handle-disposition (car h)))
575 (defun mm-get-content-id (id)
576 "Return the handle(s) referred to by ID."
577 (cdr (assoc id mm-content-id-alist)))
579 (defun mm-get-image (handle)
580 "Return an image instance based on HANDLE."
581 (let ((type (cadr (split-string (car (mm-handle-type handle)) "/")))
583 ;; Allow some common translations.
586 ((equal type "x-pixmap")
588 ((equal type "x-xbitmap")
591 (or (mm-handle-cache handle)
592 (mm-with-unibyte-buffer
593 (mm-insert-part handle)
596 (make-glyph `[,(intern type) :data ,(buffer-string)]))
597 (mm-handle-set-cache handle spec))))))
599 (defun mm-image-fit-p (handle)
600 "Say whether the image in HANDLE will fit the current window."
601 (let ((image (mm-get-image handle)))
602 (or mm-all-images-fit
603 (and (< (glyph-width image) (window-pixel-width))
604 (< (glyph-height image) (window-pixel-height))))))
608 ;; mm-decode.el ends here