1 ;;; mm-view.el --- functions for viewing MIME objects
3 ;; Copyright (C) 1998-2018 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 <https://www.gnu.org/licenses/>.
25 (eval-when-compile (require 'cl-lib
))
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 (defcustom mm-w3m-standalone-supports-m17n-p
'undecided
202 "T means the w3m command supports the m17n feature."
203 :type
'(choice (const nil
) (const t
) (other :tag
"detect" undecided
))
204 :group
'mime-display
)
206 (defun mm-w3m-standalone-supports-m17n-p ()
207 "Say whether the w3m command supports the m17n feature."
208 (cond ((eq mm-w3m-standalone-supports-m17n-p t
) t
)
209 ((eq mm-w3m-standalone-supports-m17n-p nil
) nil
)
211 (let ((coding-system-for-write 'iso-2022-jp
)
212 (coding-system-for-read 'iso-2022-jp
)
213 (str (decode-coding-string "\
214 \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
)))
215 (mm-with-multibyte-buffer
218 (point-min) (point-max) "w3m" t t nil
"-dump"
219 "-T" "text/html" "-I" "iso-2022-jp" "-O" "iso-2022-jp")
220 (goto-char (point-min))
221 (search-forward str nil t
)))
223 (setq mm-w3m-standalone-supports-m17n-p t
))
225 ;;(message "You had better upgrade your w3m command")
226 (setq mm-w3m-standalone-supports-m17n-p nil
))))
228 (defun mm-inline-text-html-render-with-w3m-standalone (handle)
229 "Render a text/html part using w3m."
230 (if (mm-w3m-standalone-supports-m17n-p)
231 (let ((source (mm-get-part handle
))
232 (charset (or (mail-content-type-get (mm-handle-type handle
)
234 (symbol-name mail-parse-charset
)))
237 (setq cs
(mm-charset-to-coding-system charset nil t
))
238 (not (eq cs
'ascii
)))
239 (setq charset
(format "%s" (mm-coding-system-to-mime-charset cs
)))
241 (setq charset
"iso-8859-1"
245 (mm-with-unibyte-buffer
247 (mm-enable-multibyte)
248 (let ((coding-system-for-write 'binary
)
249 (coding-system-for-read cs
))
251 (point-min) (point-max)
252 "w3m" t t nil
"-dump" "-T" "text/html"
253 "-I" charset
"-O" charset
))
255 (mm-inline-render-with-stdin handle nil
"w3m" "-dump" "-T" "text/html")))
257 (defun mm-links-remove-leading-blank ()
258 ;; Delete the annoying three spaces preceding each line of links
260 (goto-char (point-min))
261 (while (re-search-forward "^ " nil t
)
262 (delete-region (match-beginning 0) (match-end 0))))
264 (defun mm-inline-wash-with-file (post-func cmd
&rest args
)
265 (let ((file (make-temp-file
266 (expand-file-name "mm" mm-tmp-directory
))))
267 (let ((coding-system-for-write 'binary
))
268 (write-region (point-min) (point-max) file nil
'silent
))
269 (delete-region (point-min) (point-max))
271 (apply 'call-process cmd nil t nil
(mapcar 'eval args
))
273 (and post-func
(funcall post-func
))))
275 (defun mm-inline-wash-with-stdin (post-func cmd
&rest args
)
276 (let ((coding-system-for-write 'binary
))
277 (apply 'call-process-region
(point-min) (point-max)
279 (and post-func
(funcall post-func
)))
281 (defun mm-inline-render-with-file (handle post-func cmd
&rest args
)
282 (let ((source (mm-get-part handle
)))
285 (mm-with-unibyte-buffer
287 (apply 'mm-inline-wash-with-file post-func cmd args
)
290 (defun mm-inline-render-with-stdin (handle post-func cmd
&rest args
)
291 (let ((source (mm-get-part handle
)))
294 (mm-with-unibyte-buffer
296 (apply 'mm-inline-wash-with-stdin post-func cmd args
)
299 (defun mm-inline-render-with-function (handle func
&rest args
)
300 (let ((source (mm-get-part handle
))
301 (charset (or (mail-content-type-get (mm-handle-type handle
) 'charset
)
302 mail-parse-charset
)))
305 (mm-with-multibyte-buffer
307 (mm-decode-string source charset
)
312 (defun mm-inline-text-html (handle)
313 (if (stringp (car handle
))
314 (mapcar 'mm-inline-text-html
(cdr handle
))
315 (let* ((func mm-text-html-renderer
)
316 (entry (assq func mm-text-html-renderer-alist
))
317 (inhibit-read-only t
))
319 (setq func
(cdr entry
)))
322 (mm-insert-inline handle
(mm-get-part handle
)))
324 (funcall func handle
))
326 (apply (car func
) handle
(cdr func
)))))))
328 (defun mm-inline-text-vcard (handle)
329 (let ((inhibit-read-only t
))
334 (if (fboundp 'vcard-pretty-print
)
335 (vcard-pretty-print (mm-get-part handle
))
337 (vcard-parse-string (mm-get-part handle
)
338 'vcard-standard-filter
))))))))
340 (defun mm-inline-text (handle)
342 (type (mm-handle-media-subtype handle
))
343 (charset (mail-content-type-get
344 (mm-handle-type handle
) 'charset
))
345 (inhibit-read-only t
))
346 (if (or (eq charset
'gnus-decoded
)
347 ;; This is probably not entirely correct, but
348 ;; makes rfc822 parts with embedded multiparts work.
349 (eq mail-parse-charset
'gnus-decoded
))
351 (narrow-to-region (point) (point))
352 (mm-insert-part handle
)
353 (goto-char (point-max)))
354 (mm-display-inline-fontify handle
))
355 (when (and mm-fill-flowed
357 (equal (cdr (assoc 'format
(mm-handle-type handle
)))
360 (narrow-to-region b
(point))
362 (fill-flowed nil
(equal (cdr (assoc 'delsp
(mm-handle-type handle
)))
364 (goto-char (point-max))))
366 (narrow-to-region b
(point))
367 (when (member type
'("enriched" "richtext"))
368 (set-text-properties (point-min) (point-max) nil
)
370 (enriched-decode (point-min) (point-max))))
371 (mm-handle-set-undisplayer
374 (let ((inhibit-read-only t
))
375 (delete-region ,(copy-marker (point-min) t
)
376 ,(point-max-marker))))))))
378 (defun mm-insert-inline (handle text
)
379 "Insert TEXT inline from HANDLE."
384 (mm-handle-set-undisplayer
387 (let ((inhibit-read-only t
))
388 (delete-region ,(copy-marker b t
)
389 ,(point-marker)))))))
391 (defun mm-inline-audio (handle)
392 (message "Not implemented"))
394 (defun mm-view-message ()
395 (mm-enable-multibyte)
397 (let (gnus-article-mime-handles)
398 ;; Double decode problem may happen. See mm-inline-message.
399 (run-hooks 'gnus-article-decode-hook
)
400 (gnus-article-prepare-display)
401 (setq handles gnus-article-mime-handles
))
403 (setq gnus-article-mime-handles
404 (mm-merge-handles gnus-article-mime-handles handles
))))
406 (goto-char (point-min)))
408 (defun mm-inline-message (handle)
411 (charset (mail-content-type-get
412 (mm-handle-type handle
) 'charset
))
413 gnus-displaying-mime handles
)
416 (setq charset
(intern (downcase charset
)))
417 (when (eq charset
'us-ascii
)
421 (narrow-to-region b b
)
422 (mm-insert-part handle
)
423 (let (gnus-article-mime-handles
424 ;; disable prepare hook
425 gnus-article-prepare-hook
426 (gnus-newsgroup-charset
427 (unless (eq charset
'gnus-decoded
) ;; mm-uu might set it.
428 (or charset gnus-newsgroup-charset
))))
429 (let ((gnus-original-article-buffer (mm-handle-buffer handle
)))
430 (run-hooks 'gnus-article-decode-hook
))
431 (gnus-article-prepare-display)
432 (setq handles gnus-article-mime-handles
))
433 (goto-char (point-min))
436 (goto-char (point-max))
439 (insert "----------\n\n")
441 (setq gnus-article-mime-handles
442 (mm-merge-handles gnus-article-mime-handles handles
)))
443 (mm-handle-set-undisplayer
446 (let ((inhibit-read-only t
))
447 (delete-region ,(point-min-marker) ,(point-max-marker)))))))))
449 ;; Shut up byte-compiler.
450 (defvar font-lock-mode-hook
)
451 (defun mm-display-inline-fontify (handle &optional mode
)
452 "Insert HANDLE inline fontifying with MODE.
453 If MODE is not set, try to find mode automatically."
454 (let ((charset (mail-content-type-get (mm-handle-type handle
) 'charset
))
455 text coding-system ovs
)
456 (unless (eq charset
'gnus-decoded
)
457 (mm-with-unibyte-buffer
458 (mm-insert-part handle
)
459 (mm-decompress-buffer
460 (mm-handle-filename handle
)
463 (setq coding-system
(mm-find-buffer-file-coding-system)))
464 (setq text
(buffer-string))))
466 (buffer-disable-undo)
467 (mm-enable-multibyte)
468 (insert (cond ((eq charset
'gnus-decoded
)
469 (with-current-buffer (mm-handle-buffer handle
)
472 (decode-coding-string text coding-system
))
474 (mm-decode-string text charset
))
478 ;; I find font-lock a bit too verbose.
479 (let ((font-lock-verbose nil
)
480 (font-lock-support-mode nil
)
481 (enable-local-variables nil
))
482 ;; Disable support modes, e.g., jit-lock, lazy-lock, etc.
483 ;; Note: XEmacs people use `font-lock-mode-hook' to run those modes.
484 (set (make-local-variable 'font-lock-mode-hook
) nil
)
485 (setq buffer-file-name
(mm-handle-filename handle
))
488 (save-window-excursion
489 (switch-to-buffer (current-buffer))
491 (let ((auto-mode-alist
492 (delq (rassq 'doc-view-mode-maybe auto-mode-alist
)
493 (copy-sequence auto-mode-alist
))))
495 ;; The mode function might have already turned on font-lock.
496 ;; Do not fontify if the guess mode is fundamental.
497 (unless (or font-lock-mode
498 (eq major-mode
'fundamental-mode
))
499 (font-lock-ensure))))
500 (setq text
(buffer-string))
501 (when (eq mode
'diff-mode
)
502 (setq ovs
(mapcar (lambda (ov) (list ov
(overlay-start ov
)
504 (overlays-in (point-min) (point-max)))))
505 ;; Set buffer unmodified to avoid confirmation when killing the
507 (set-buffer-modified-p nil
))
508 (let ((b (1- (point))))
509 (mm-insert-inline handle text
)
511 (move-overlay (nth 0 ov
) (+ (nth 1 ov
) b
)
512 (+ (nth 2 ov
) b
) (current-buffer))))))
514 ;; Shouldn't these functions check whether the user even wants to use
515 ;; font-lock? Also, it would be nice to change for the size of the
518 (defun mm-display-patch-inline (handle)
519 (mm-display-inline-fontify handle
'diff-mode
))
521 (defun mm-display-elisp-inline (handle)
522 (mm-display-inline-fontify handle
'emacs-lisp-mode
))
524 (defun mm-display-dns-inline (handle)
525 (mm-display-inline-fontify handle
'dns-mode
))
527 (defun mm-display-org-inline (handle)
528 "Show an Org mode text from HANDLE inline."
529 (mm-display-inline-fontify handle
'org-mode
))
531 (defun mm-display-shell-script-inline (handle)
532 "Show a shell script from HANDLE inline."
533 (mm-display-inline-fontify handle
'shell-script-mode
))
535 (defun mm-display-javascript-inline (handle)
536 "Show JavsScript code from HANDLE inline."
537 (mm-display-inline-fontify handle
'javascript-mode
))
539 ;; id-signedData OBJECT IDENTIFIER ::= { iso(1) member-body(2)
540 ;; us(840) rsadsi(113549) pkcs(1) pkcs7(7) 2 }
541 (defvar mm-pkcs7-signed-magic
545 "\\|\\(\x81\\(.\\|\n\\)\\{1\\}\\)"
546 "\\|\\(\x82\\(.\\|\n\\)\\{2\\}\\)"
547 "\\|\\(\x83\\(.\\|\n\\)\\{3\\}\\)"
549 "\x06\x09\\*\x86H\x86\xf7\x0d\x01\x07\x02"))
551 ;; id-envelopedData OBJECT IDENTIFIER ::= { iso(1) member-body(2)
552 ;; us(840) rsadsi(113549) pkcs(1) pkcs7(7) 3 }
553 (defvar mm-pkcs7-enveloped-magic
557 "\\|\\(\x81\\(.\\|\n\\)\\{1\\}\\)"
558 "\\|\\(\x82\\(.\\|\n\\)\\{2\\}\\)"
559 "\\|\\(\x83\\(.\\|\n\\)\\{3\\}\\)"
561 "\x06\x09\\*\x86H\x86\xf7\x0d\x01\x07\x03"))
563 (defun mm-view-pkcs7-get-type (handle)
564 (mm-with-unibyte-buffer
565 (mm-insert-part handle
)
566 (cond ((looking-at mm-pkcs7-enveloped-magic
)
568 ((looking-at mm-pkcs7-signed-magic
)
571 (error "Could not identify PKCS#7 type")))))
573 (defun mm-view-pkcs7 (handle &optional from
)
574 (cl-case (mm-view-pkcs7-get-type handle
)
575 (enveloped (mm-view-pkcs7-decrypt handle from
))
576 (signed (mm-view-pkcs7-verify handle
))
577 (otherwise (error "Unknown or unimplemented PKCS#7 type"))))
579 (defun mm-view-pkcs7-verify (handle)
580 (let ((verified nil
))
582 (insert "MIME-Version: 1.0\n")
583 (mm-insert-headers "application/pkcs7-mime" "base64" "smime.p7m")
584 (insert-buffer-substring (mm-handle-buffer handle
))
585 (setq verified
(smime-verify-region (point-min) (point-max))))
586 (goto-char (point-min))
587 (mm-insert-part handle
)
588 (if (search-forward "Content-Type: " nil t
)
589 (delete-region (point-min) (match-beginning 0)))
590 (goto-char (point-max))
591 (if (re-search-backward "--\r?\n?" nil t
)
592 (delete-region (match-end 0) (point-max)))
594 (insert-buffer-substring smime-details-buffer
)))
595 (goto-char (point-min))
596 (while (search-forward "\r\n" nil t
)
597 (replace-match "\n"))
600 (autoload 'epg-decrypt-string
"epg")
602 (defun mm-view-pkcs7-decrypt (handle &optional from
)
603 (insert-buffer-substring (mm-handle-buffer handle
))
604 (goto-char (point-min))
605 (if (eq mml-smime-use
'epg
)
607 (let ((part (base64-decode-string (buffer-string))))
609 (insert (epg-decrypt-string (epg-make-context 'CMS
) part
)))
611 (insert "MIME-Version: 1.0\n")
612 (mm-insert-headers "application/pkcs7-mime" "base64" "smime.p7m")
613 (smime-decrypt-region
614 (point-min) (point-max)
615 (if (= (length smime-keys
) 1)
617 (smime-get-key-by-email
618 (gnus-completing-read
620 smime-keys nil nil nil
(car-safe (car-safe smime-keys
)))))
622 (goto-char (point-min))
623 (while (search-forward "\r\n" nil t
)
624 (replace-match "\n"))
625 (goto-char (point-min)))
629 ;;; mm-view.el ends here