1 ;;; mm-view.el --- functions for viewing MIME objects
3 ;; Copyright (C) 1998-2016 Free Software Foundation, Inc.
5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
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 3 of the License, or
11 ;; (at your option) any later version.
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. If not, see <http://www.gnu.org/licenses/>.
25 (eval-when-compile (require 'cl))
33 (autoload 'gnus-completing-read "gnus-util")
34 (autoload 'gnus-article-prepare-display "gnus-art")
35 (autoload 'vcard-parse-string "vcard")
36 (autoload 'vcard-format-string "vcard")
37 (autoload 'fill-flowed "flow-fill")
38 (autoload 'html2text "html2text" nil t)
40 (defvar gnus-article-mime-handles)
41 (defvar gnus-newsgroup-charset)
43 (defvar w3m-cid-retrieve-function-alist)
44 (defvar w3m-current-buffer)
45 (defvar w3m-display-inline-images)
46 (defvar w3m-minor-mode-map)
48 (defvar mm-text-html-renderer-alist
50 (w3m . mm-inline-text-html-render-with-w3m)
51 (w3m-standalone . mm-inline-text-html-render-with-w3m-standalone)
52 (gnus-w3m . gnus-article-html)
53 (links mm-inline-render-with-file
54 mm-links-remove-leading-blank
56 (lynx mm-inline-render-with-stdin nil
57 "lynx" "-dump" "-force_html" "-stdin" "-nolist")
58 (html2text mm-inline-render-with-function html2text))
59 "The attributes of renderer types for text/html.")
61 (defcustom mm-fill-flowed t
62 "If non-nil a format=flowed article will be displayed flowed."
67 (defcustom mm-inline-large-images-proportion 0.9
68 "Maximum proportion of large image resized when
69 `mm-inline-large-images' is set to resize."
74 ;;; Internal variables.
77 ;;; Functions for displaying various formats inline
80 (autoload 'gnus-rescale-image "gnus-util")
82 (defun mm-inline-image (handle)
83 (let ((b (point-marker))
84 (inhibit-read-only t))
86 (let ((image (mm-get-image handle)))
87 (if (eq mm-inline-large-images 'resize)
90 (let ((edges (window-inside-pixel-edges
91 (get-buffer-window (current-buffer)))))
92 (cons (truncate (* mm-inline-large-images-proportion
93 (- (nth 2 edges) (nth 0 edges))))
94 (truncate (* mm-inline-large-images-proportion
95 (- (nth 3 edges) (nth 1 edges)))))))
99 (mm-handle-set-undisplayer
103 (inhibit-read-only t))
105 (delete-region b (1+ b)))))))
107 (defvar mm-w3m-setup nil
108 "Whether gnus-article-mode has been setup to use emacs-w3m.")
111 (declare-function w3m-detect-meta-charset "ext:w3m" ())
112 (declare-function w3m-region "ext:w3m" (start end &optional url charset))
114 (defun mm-setup-w3m ()
115 "Setup gnus-article-mode to use emacs-w3m."
118 (unless (assq 'gnus-article-mode w3m-cid-retrieve-function-alist)
119 (push (cons 'gnus-article-mode 'mm-w3m-cid-retrieve)
120 w3m-cid-retrieve-function-alist))
121 (setq mm-w3m-setup t))
122 (setq w3m-display-inline-images (not mm-html-inhibit-images)))
124 (defun mm-w3m-cid-retrieve-1 (url handle)
125 (dolist (elem handle)
127 (when (equal url (mm-handle-id elem))
128 (mm-insert-part elem)
129 (throw 'found-handle (mm-handle-media-type elem)))
130 (when (and (stringp (car elem))
131 (equal "multipart" (mm-handle-media-supertype elem)))
132 (mm-w3m-cid-retrieve-1 url elem)))))
134 (defun mm-w3m-cid-retrieve (url &rest args)
135 "Insert a content pointed by URL if it has the cid: scheme."
136 (when (string-match "\\`cid:" url)
137 (or (catch 'found-handle
138 (mm-w3m-cid-retrieve-1
139 (setq url (concat "<" (substring url (match-end 0)) ">"))
140 (with-current-buffer w3m-current-buffer
141 gnus-article-mime-handles)))
144 (message "Failed to find \"Content-ID: %s\"" url)))))
146 (defun mm-inline-text-html-render-with-w3m (handle)
147 "Render a text/html part using emacs-w3m."
149 (let ((text (mm-get-part handle))
151 (charset (or (mail-content-type-get (mm-handle-type handle) 'charset)
152 mail-parse-charset)))
154 (insert (if charset (mm-decode-string text charset) text))
156 (narrow-to-region b (point))
158 (goto-char (point-min))
159 (when (setq charset (w3m-detect-meta-charset))
160 (delete-region (point-min) (point-max))
161 (insert (mm-decode-string text charset))))
162 (let ((w3m-safe-url-regexp mm-w3m-safe-url-regexp)
164 (w3m-region (point-min) (point-max) nil charset))
165 ;; Put the mark meaning this part was rendered by emacs-w3m.
166 (put-text-property (point-min) (point-max)
167 'mm-inline-text-html-with-w3m t)
168 (when (and mm-inline-text-html-with-w3m-keymap
169 (boundp 'w3m-minor-mode-map)
171 (if (and (boundp 'w3m-link-map)
173 (let* ((start (point-min))
175 (on (get-text-property start 'w3m-href-anchor))
176 (map (copy-keymap w3m-link-map))
178 (set-keymap-parent map w3m-minor-mode-map)
182 (setq next (or (text-property-any start end
183 'w3m-href-anchor nil)
185 (put-text-property start next 'keymap map))
186 (setq next (or (text-property-not-all start end
187 'w3m-href-anchor nil)
189 (put-text-property start next 'keymap w3m-minor-mode-map))
192 (put-text-property (point-min) (point-max)
193 'keymap w3m-minor-mode-map)))
194 (mm-handle-set-undisplayer
197 (let ((inhibit-read-only t))
198 (delete-region ,(point-min-marker)
199 ,(point-max-marker)))))))))
201 (defvar mm-w3m-standalone-supports-m17n-p 'undecided
202 "*T means the w3m command supports the m17n feature.")
204 (defun mm-w3m-standalone-supports-m17n-p ()
205 "Say whether the w3m command supports the m17n feature."
206 (cond ((eq mm-w3m-standalone-supports-m17n-p t) t)
207 ((eq mm-w3m-standalone-supports-m17n-p nil) nil)
209 (let ((coding-system-for-write 'iso-2022-jp)
210 (coding-system-for-read 'iso-2022-jp)
211 (str (decode-coding-string "\
212 \e$B#D#o#e#s!!#w#3#m!!#s#u#p#p#o#r#t!!#m#1#7#n!)\e(B" 'iso-2022-jp)))
213 (mm-with-multibyte-buffer
216 (point-min) (point-max) "w3m" t t nil "-dump"
217 "-T" "text/html" "-I" "iso-2022-jp" "-O" "iso-2022-jp")
218 (goto-char (point-min))
219 (search-forward str nil t)))
221 (setq mm-w3m-standalone-supports-m17n-p t))
223 ;;(message "You had better upgrade your w3m command")
224 (setq mm-w3m-standalone-supports-m17n-p nil))))
226 (defun mm-inline-text-html-render-with-w3m-standalone (handle)
227 "Render a text/html part using w3m."
228 (if (mm-w3m-standalone-supports-m17n-p)
229 (let ((source (mm-get-part handle))
230 (charset (or (mail-content-type-get (mm-handle-type handle)
232 (symbol-name mail-parse-charset)))
235 (setq cs (mm-charset-to-coding-system charset nil t))
236 (not (eq cs 'ascii)))
237 (setq charset (format "%s" (mm-coding-system-to-mime-charset cs)))
239 (setq charset "iso-8859-1"
243 (mm-with-unibyte-buffer
245 (mm-enable-multibyte)
246 (let ((coding-system-for-write 'binary)
247 (coding-system-for-read cs))
249 (point-min) (point-max)
250 "w3m" t t nil "-dump" "-T" "text/html"
251 "-I" charset "-O" charset))
253 (mm-inline-render-with-stdin handle nil "w3m" "-dump" "-T" "text/html")))
255 (defun mm-links-remove-leading-blank ()
256 ;; Delete the annoying three spaces preceding each line of links
258 (goto-char (point-min))
259 (while (re-search-forward "^ " nil t)
260 (delete-region (match-beginning 0) (match-end 0))))
262 (defun mm-inline-wash-with-file (post-func cmd &rest args)
263 (let ((file (make-temp-file
264 (expand-file-name "mm" mm-tmp-directory))))
265 (let ((coding-system-for-write 'binary))
266 (write-region (point-min) (point-max) file nil 'silent))
267 (delete-region (point-min) (point-max))
269 (apply 'call-process cmd nil t nil (mapcar 'eval args))
271 (and post-func (funcall post-func))))
273 (defun mm-inline-wash-with-stdin (post-func cmd &rest args)
274 (let ((coding-system-for-write 'binary))
275 (apply 'call-process-region (point-min) (point-max)
277 (and post-func (funcall post-func)))
279 (defun mm-inline-render-with-file (handle post-func cmd &rest args)
280 (let ((source (mm-get-part handle)))
283 (mm-with-unibyte-buffer
285 (apply 'mm-inline-wash-with-file post-func cmd args)
288 (defun mm-inline-render-with-stdin (handle post-func cmd &rest args)
289 (let ((source (mm-get-part handle)))
292 (mm-with-unibyte-buffer
294 (apply 'mm-inline-wash-with-stdin post-func cmd args)
297 (defun mm-inline-render-with-function (handle func &rest args)
298 (let ((source (mm-get-part handle))
299 (charset (or (mail-content-type-get (mm-handle-type handle) 'charset)
300 mail-parse-charset)))
303 (mm-with-multibyte-buffer
305 (mm-decode-string source charset)
310 (defun mm-inline-text-html (handle)
311 (if (stringp (car handle))
312 (mapcar 'mm-inline-text-html (cdr handle))
313 (let* ((func mm-text-html-renderer)
314 (entry (assq func mm-text-html-renderer-alist))
315 (inhibit-read-only t))
317 (setq func (cdr entry)))
320 (funcall func handle))
322 (apply (car func) handle (cdr func)))))))
324 (defun mm-inline-text-vcard (handle)
325 (let ((inhibit-read-only t))
330 (if (fboundp 'vcard-pretty-print)
331 (vcard-pretty-print (mm-get-part handle))
333 (vcard-parse-string (mm-get-part handle)
334 'vcard-standard-filter))))))))
336 (defun mm-inline-text (handle)
338 (type (mm-handle-media-subtype handle))
339 (charset (mail-content-type-get
340 (mm-handle-type handle) 'charset))
341 (inhibit-read-only t))
342 (if (or (eq charset 'gnus-decoded)
343 ;; This is probably not entirely correct, but
344 ;; makes rfc822 parts with embedded multiparts work.
345 (eq mail-parse-charset 'gnus-decoded))
347 (narrow-to-region (point) (point))
348 (mm-insert-part handle)
349 (goto-char (point-max)))
350 (mm-display-inline-fontify handle))
351 (when (and mm-fill-flowed
353 (equal (cdr (assoc 'format (mm-handle-type handle)))
356 (narrow-to-region b (point))
358 (fill-flowed nil (equal (cdr (assoc 'delsp (mm-handle-type handle)))
360 (goto-char (point-max))))
362 (narrow-to-region b (point))
363 (when (member type '("enriched" "richtext"))
364 (set-text-properties (point-min) (point-max) nil)
366 (enriched-decode (point-min) (point-max))))
367 (mm-handle-set-undisplayer
370 (let ((inhibit-read-only t))
371 (delete-region ,(copy-marker (point-min) t)
372 ,(point-max-marker))))))))
374 (defun mm-insert-inline (handle text)
375 "Insert TEXT inline from HANDLE."
380 (mm-handle-set-undisplayer
383 (let ((inhibit-read-only t))
384 (delete-region ,(copy-marker b t)
385 ,(point-marker)))))))
387 (defun mm-inline-audio (handle)
388 (message "Not implemented"))
390 (defun mm-view-message ()
391 (mm-enable-multibyte)
393 (let (gnus-article-mime-handles)
394 ;; Double decode problem may happen. See mm-inline-message.
395 (run-hooks 'gnus-article-decode-hook)
396 (gnus-article-prepare-display)
397 (setq handles gnus-article-mime-handles))
399 (setq gnus-article-mime-handles
400 (mm-merge-handles gnus-article-mime-handles handles))))
402 (goto-char (point-min)))
404 (defun mm-inline-message (handle)
407 (charset (mail-content-type-get
408 (mm-handle-type handle) 'charset))
409 gnus-displaying-mime handles)
412 (setq charset (intern (downcase charset)))
413 (when (eq charset 'us-ascii)
417 (narrow-to-region b b)
418 (mm-insert-part handle)
419 (let (gnus-article-mime-handles
420 ;; disable prepare hook
421 gnus-article-prepare-hook
422 (gnus-newsgroup-charset
423 (unless (eq charset 'gnus-decoded) ;; mm-uu might set it.
424 (or charset gnus-newsgroup-charset))))
425 (let ((gnus-original-article-buffer (mm-handle-buffer handle)))
426 (run-hooks 'gnus-article-decode-hook))
427 (gnus-article-prepare-display)
428 (setq handles gnus-article-mime-handles))
429 (goto-char (point-min))
432 (goto-char (point-max))
435 (insert "----------\n\n")
437 (setq gnus-article-mime-handles
438 (mm-merge-handles gnus-article-mime-handles handles)))
439 (mm-handle-set-undisplayer
442 (let ((inhibit-read-only t))
443 (delete-region ,(point-min-marker) ,(point-max-marker)))))))))
445 ;; Shut up byte-compiler.
446 (defvar font-lock-mode-hook)
447 (defun mm-display-inline-fontify (handle &optional mode)
448 "Insert HANDLE inline fontifying with MODE.
449 If MODE is not set, try to find mode automatically."
450 (let ((charset (mail-content-type-get (mm-handle-type handle) 'charset))
452 (unless (eq charset 'gnus-decoded)
453 (mm-with-unibyte-buffer
454 (mm-insert-part handle)
455 (mm-decompress-buffer
456 (mm-handle-filename handle)
459 (setq coding-system (mm-find-buffer-file-coding-system)))
460 (setq text (buffer-string))))
462 (buffer-disable-undo)
463 (mm-enable-multibyte)
464 (insert (cond ((eq charset 'gnus-decoded)
465 (with-current-buffer (mm-handle-buffer handle)
468 (decode-coding-string text coding-system))
470 (mm-decode-string text charset))
474 ;; I find font-lock a bit too verbose.
475 (let ((font-lock-verbose nil)
476 (font-lock-support-mode nil))
477 ;; Disable support modes, e.g., jit-lock, lazy-lock, etc.
478 ;; Note: XEmacs people use `font-lock-mode-hook' to run those modes.
479 (set (make-local-variable 'font-lock-mode-hook) nil)
480 (setq buffer-file-name (mm-handle-filename handle))
481 (set (make-local-variable 'enable-local-variables) nil)
484 (save-window-excursion
485 (switch-to-buffer (current-buffer))
487 (let ((auto-mode-alist
488 (delq (rassq 'doc-view-mode-maybe auto-mode-alist)
489 (copy-sequence auto-mode-alist))))
491 ;; The mode function might have already turned on font-lock.
492 ;; Do not fontify if the guess mode is fundamental.
493 (unless (or font-lock-mode
494 (eq major-mode 'fundamental-mode))
495 (font-lock-ensure))))
496 (setq text (buffer-string))
497 ;; Set buffer unmodified to avoid confirmation when killing the
499 (set-buffer-modified-p nil))
500 (mm-insert-inline handle text)))
502 ;; Shouldn't these functions check whether the user even wants to use
503 ;; font-lock? Also, it would be nice to change for the size of the
506 (defun mm-display-patch-inline (handle)
507 (mm-display-inline-fontify handle 'diff-mode))
509 (defun mm-display-elisp-inline (handle)
510 (mm-display-inline-fontify handle 'emacs-lisp-mode))
512 (defun mm-display-dns-inline (handle)
513 (mm-display-inline-fontify handle 'dns-mode))
515 (defun mm-display-org-inline (handle)
516 "Show an Org mode text from HANDLE inline."
517 (mm-display-inline-fontify handle 'org-mode))
519 (defun mm-display-shell-script-inline (handle)
520 "Show a shell script from HANDLE inline."
521 (mm-display-inline-fontify handle 'shell-script-mode))
523 (defun mm-display-javascript-inline (handle)
524 "Show JavsScript code from HANDLE inline."
525 (mm-display-inline-fontify handle 'javascript-mode))
527 ;; id-signedData OBJECT IDENTIFIER ::= { iso(1) member-body(2)
528 ;; us(840) rsadsi(113549) pkcs(1) pkcs7(7) 2 }
529 (defvar mm-pkcs7-signed-magic
533 "\\|\\(\x81\\(.\\|\n\\)\\{1\\}\\)"
534 "\\|\\(\x82\\(.\\|\n\\)\\{2\\}\\)"
535 "\\|\\(\x83\\(.\\|\n\\)\\{3\\}\\)"
537 "\x06\x09\\*\x86H\x86\xf7\x0d\x01\x07\x02"))
539 ;; id-envelopedData OBJECT IDENTIFIER ::= { iso(1) member-body(2)
540 ;; us(840) rsadsi(113549) pkcs(1) pkcs7(7) 3 }
541 (defvar mm-pkcs7-enveloped-magic
545 "\\|\\(\x81\\(.\\|\n\\)\\{1\\}\\)"
546 "\\|\\(\x82\\(.\\|\n\\)\\{2\\}\\)"
547 "\\|\\(\x83\\(.\\|\n\\)\\{3\\}\\)"
549 "\x06\x09\\*\x86H\x86\xf7\x0d\x01\x07\x03"))
551 (defun mm-view-pkcs7-get-type (handle)
552 (mm-with-unibyte-buffer
553 (mm-insert-part handle)
554 (cond ((looking-at mm-pkcs7-enveloped-magic)
556 ((looking-at mm-pkcs7-signed-magic)
559 (error "Could not identify PKCS#7 type")))))
561 (defun mm-view-pkcs7 (handle &optional from)
562 (case (mm-view-pkcs7-get-type handle)
563 (enveloped (mm-view-pkcs7-decrypt handle from))
564 (signed (mm-view-pkcs7-verify handle))
565 (otherwise (error "Unknown or unimplemented PKCS#7 type"))))
567 (defun mm-view-pkcs7-verify (handle)
568 (let ((verified nil))
570 (insert "MIME-Version: 1.0\n")
571 (mm-insert-headers "application/pkcs7-mime" "base64" "smime.p7m")
572 (insert-buffer-substring (mm-handle-buffer handle))
573 (setq verified (smime-verify-region (point-min) (point-max))))
574 (goto-char (point-min))
575 (mm-insert-part handle)
576 (if (search-forward "Content-Type: " nil t)
577 (delete-region (point-min) (match-beginning 0)))
578 (goto-char (point-max))
579 (if (re-search-backward "--\r?\n?" nil t)
580 (delete-region (match-end 0) (point-max)))
582 (insert-buffer-substring smime-details-buffer)))
583 (goto-char (point-min))
584 (while (search-forward "\r\n" nil t)
585 (replace-match "\n"))
588 (autoload 'epg-decrypt-string "epg")
590 (defun mm-view-pkcs7-decrypt (handle &optional from)
591 (insert-buffer-substring (mm-handle-buffer handle))
592 (goto-char (point-min))
593 (if (eq mml-smime-use 'epg)
595 (let ((part (base64-decode-string (buffer-string))))
597 (insert (epg-decrypt-string (epg-make-context 'CMS) part)))
599 (insert "MIME-Version: 1.0\n")
600 (mm-insert-headers "application/pkcs7-mime" "base64" "smime.p7m")
601 (smime-decrypt-region
602 (point-min) (point-max)
603 (if (= (length smime-keys) 1)
605 (smime-get-key-by-email
606 (gnus-completing-read
608 smime-keys nil nil nil (car-safe (car-safe smime-keys)))))
610 (goto-char (point-min))
611 (while (search-forward "\r\n" nil t)
612 (replace-match "\n"))
613 (goto-char (point-min)))
617 ;;; mm-view.el ends here