lisp/gnus/mm-decode.el

   1 ;;; mm-decode.el --- Functions for decoding MIME things
   2
   3 ;; Copyright (C) 1998-2012 Free Software Foundation, Inc.
   4
   5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   6 ;;      MORIOKA Tomohiko <morioka@jaist.ac.jp>
   7 ;; This file is part of GNU Emacs.
   8
   9 ;; GNU Emacs is free software: you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation, either version 3 of the License, or
  12 ;; (at your option) any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  21
  22 ;;; Commentary:
  23
  24 ;;; Code:
  25
  26 ;; For Emacs <22.2 and XEmacs.
  27 (eval-and-compile
  28   (unless (fboundp 'declare-function) (defmacro declare-function (&rest r))))
  29
  30 (require 'mail-parse)
  31 (require 'mm-bodies)
  32 (eval-when-compile (require 'cl)
  33                    (require 'term))
  34
  35 (autoload 'gnus-map-function "gnus-util")
  36 (autoload 'gnus-replace-in-string "gnus-util")
  37 (autoload 'gnus-read-shell-command "gnus-util")
  38
  39 (autoload 'mm-inline-partial "mm-partial")
  40 (autoload 'mm-inline-external-body "mm-extern")
  41 (autoload 'mm-extern-cache-contents "mm-extern")
  42 (autoload 'mm-insert-inline "mm-view")
  43
  44 (autoload 'mm-archive-decoders "mm-archive")
  45 (autoload 'mm-archive-dissect-and-inline "mm-archive")
  46 (autoload 'mm-dissect-archive "mm-archive")
  47
  48 (defvar gnus-current-window-configuration)
  49
  50 (add-hook 'gnus-exit-gnus-hook 'mm-destroy-postponed-undisplay-list)
  51
  52 (defgroup mime-display ()
  53   "Display of MIME in mail and news articles."
  54   :link '(custom-manual "(emacs-mime)Display Customization")
  55   :version "21.1"
  56   :group 'mail
  57   :group 'news
  58   :group 'multimedia)
  59
  60 (defgroup mime-security ()
  61   "MIME security in mail and news articles."
  62   :link '(custom-manual "(emacs-mime)Display Customization")
  63   :group 'mail
  64   :group 'news
  65   :group 'multimedia)
  66
  67 ;;; Convenience macros.
  68
  69 (defmacro mm-handle-buffer (handle)
  70   `(nth 0 ,handle))
  71 (defmacro mm-handle-type (handle)
  72   `(nth 1 ,handle))
  73 (defsubst mm-handle-media-type (handle)
  74   (if (stringp (car handle))
  75       (car handle)
  76     (car (mm-handle-type handle))))
  77 (defsubst mm-handle-media-supertype (handle)
  78   (car (split-string (mm-handle-media-type handle) "/")))
  79 (defsubst mm-handle-media-subtype (handle)
  80   (cadr (split-string (mm-handle-media-type handle) "/")))
  81 (defmacro mm-handle-encoding (handle)
  82   `(nth 2 ,handle))
  83 (defmacro mm-handle-undisplayer (handle)
  84   `(nth 3 ,handle))
  85 (defmacro mm-handle-set-undisplayer (handle function)
  86   `(setcar (nthcdr 3 ,handle) ,function))
  87 (defmacro mm-handle-disposition (handle)
  88   `(nth 4 ,handle))
  89 (defmacro mm-handle-description (handle)
  90   `(nth 5 ,handle))
  91 (defmacro mm-handle-cache (handle)
  92   `(nth 6 ,handle))
  93 (defmacro mm-handle-set-cache (handle contents)
  94   `(setcar (nthcdr 6 ,handle) ,contents))
  95 (defmacro mm-handle-id (handle)
  96   `(nth 7 ,handle))
  97 (defmacro mm-handle-multipart-original-buffer (handle)
  98   `(get-text-property 0 'buffer (car ,handle)))
  99 (defmacro mm-handle-multipart-from (handle)
 100   `(get-text-property 0 'from (car ,handle)))
 101 (defmacro mm-handle-multipart-ctl-parameter (handle parameter)
 102   `(get-text-property 0 ,parameter (car ,handle)))
 103
 104 (defmacro mm-make-handle (&optional buffer type encoding undisplayer
 105                                     disposition description cache
 106                                     id)
 107   `(list ,buffer ,type ,encoding ,undisplayer
 108          ,disposition ,description ,cache ,id))
 109
 110 (defcustom mm-text-html-renderer
 111   (cond ((fboundp 'libxml-parse-html-region) 'shr)
 112         ((executable-find "w3m") 'gnus-w3m)
 113         ((executable-find "links") 'links)
 114         ((executable-find "lynx") 'lynx)
 115         ((locate-library "w3") 'w3)
 116         ((locate-library "html2text") 'html2text)
 117         (t nil))
 118   "Render of HTML contents.
 119 It is one of defined renderer types, or a rendering function.
 120 The defined renderer types are:
 121 `shr': use the built-in Gnus HTML renderer;
 122 `gnus-w3m': use Gnus renderer based on w3m;
 123 `w3m': use emacs-w3m;
 124 `w3m-standalone': use plain w3m;
 125 `links': use links;
 126 `lynx': use lynx;
 127 `w3': use Emacs/W3;
 128 `html2text': use html2text;
 129 nil    : use external viewer (default web browser)."
 130   :version "24.1"
 131   :type '(choice (const shr)
 132                  (const gnus-w3m)
 133                  (const w3)
 134                  (const w3m :tag "emacs-w3m")
 135                  (const w3m-standalone :tag "standalone w3m" )
 136                  (const links)
 137                  (const lynx)
 138                  (const html2text)
 139                  (const nil :tag "External viewer")
 140                  (function))
 141   :group 'mime-display)
 142
 143 (defcustom mm-inline-text-html-with-images nil
 144   "If non-nil, Gnus will allow retrieving images in HTML contents with
 145 the <img> tags.  It has no effect on Emacs/w3.  See also the
 146 documentation for the `mm-w3m-safe-url-regexp' variable."
 147   :version "22.1"
 148   :type 'boolean
 149   :group 'mime-display)
 150
 151 (defcustom mm-w3m-safe-url-regexp "\\`cid:"
 152   "Regexp matching URLs which are considered to be safe.
 153 Some HTML mails might contain a nasty trick used by spammers, using
 154 the <img> tag which is far more evil than the [Click Here!] button.
 155 It is most likely intended to check whether the ominous spam mail has
 156 reached your eyes or not, in which case the spammer knows for sure
 157 that your email address is valid.  It is done by embedding an
 158 identifier string into a URL that you might automatically retrieve
 159 when displaying the image.  The default value is \"\\\\`cid:\" which only
 160 matches parts embedded to the Multipart/Related type MIME contents and
 161 Gnus will never connect to the spammer's site arbitrarily.  You may
 162 set this variable to nil if you consider all urls to be safe."
 163   :version "22.1"
 164   :type '(choice (regexp :tag "Regexp")
 165                  (const :tag "All URLs are safe" nil))
 166   :group 'mime-display)
 167
 168 (defcustom mm-inline-text-html-with-w3m-keymap t
 169   "If non-nil, use emacs-w3m command keys in the article buffer."
 170   :version "22.1"
 171   :type 'boolean
 172   :group 'mime-display)
 173
 174 (defcustom mm-enable-external t
 175   "Indicate whether external MIME handlers should be used.
 176
 177 If t, all defined external MIME handlers are used.  If nil, files are saved by
 178 `mailcap-save-binary-file'.  If it is the symbol `ask', you are prompted
 179 before the external MIME handler is invoked."
 180   :version "22.1"
 181   :type '(choice (const :tag "Always" t)
 182                  (const :tag "Never" nil)
 183                  (const :tag "Ask" ask))
 184   :group 'mime-display)
 185
 186 (defcustom mm-inline-media-tests
 187   '(("image/p?jpeg"
 188      mm-inline-image
 189      (lambda (handle)
 190        (mm-valid-and-fit-image-p 'jpeg handle)))
 191     ("image/png"
 192      mm-inline-image
 193      (lambda (handle)
 194        (mm-valid-and-fit-image-p 'png handle)))
 195     ("image/gif"
 196      mm-inline-image
 197      (lambda (handle)
 198        (mm-valid-and-fit-image-p 'gif handle)))
 199     ("image/tiff"
 200      mm-inline-image
 201      (lambda (handle)
 202        (mm-valid-and-fit-image-p 'tiff handle)))
 203     ("image/xbm"
 204      mm-inline-image
 205      (lambda (handle)
 206        (mm-valid-and-fit-image-p 'xbm handle)))
 207     ("image/x-xbitmap"
 208      mm-inline-image
 209      (lambda (handle)
 210        (mm-valid-and-fit-image-p 'xbm handle)))
 211     ("image/xpm"
 212      mm-inline-image
 213      (lambda (handle)
 214        (mm-valid-and-fit-image-p 'xpm handle)))
 215     ("image/x-xpixmap"
 216      mm-inline-image
 217      (lambda (handle)
 218        (mm-valid-and-fit-image-p 'xpm handle)))
 219     ("image/bmp"
 220      mm-inline-image
 221      (lambda (handle)
 222        (mm-valid-and-fit-image-p 'bmp handle)))
 223     ("image/x-portable-bitmap"
 224      mm-inline-image
 225      (lambda (handle)
 226        (mm-valid-and-fit-image-p 'pbm handle)))
 227     ("text/plain" mm-inline-text identity)
 228     ("text/enriched" mm-inline-text identity)
 229     ("text/richtext" mm-inline-text identity)
 230     ("text/x-patch" mm-display-patch-inline identity)
 231     ;; In case mime.types uses x-diff (as does Debian's mime-support-3.40).
 232     ("text/x-diff" mm-display-patch-inline identity)
 233     ("application/emacs-lisp" mm-display-elisp-inline identity)
 234     ("application/x-emacs-lisp" mm-display-elisp-inline identity)
 235     ("application/x-shellscript" mm-display-shell-script-inline identity)
 236     ("application/x-sh" mm-display-shell-script-inline identity)
 237     ("text/x-sh" mm-display-shell-script-inline identity)
 238     ("application/javascript" mm-display-javascript-inline identity)
 239     ("text/dns" mm-display-dns-inline identity)
 240     ("text/x-org" mm-display-org-inline identity)
 241     ("text/html"
 242      mm-inline-text-html
 243      (lambda (handle)
 244        mm-text-html-renderer))
 245     ("text/x-vcard"
 246      mm-inline-text-vcard
 247      (lambda (handle)
 248        (or (featurep 'vcard)
 249            (locate-library "vcard"))))
 250     ("message/delivery-status" mm-inline-text identity)
 251     ("message/rfc822" mm-inline-message identity)
 252     ("message/partial" mm-inline-partial identity)
 253     ("message/external-body" mm-inline-external-body identity)
 254     ("text/.*" mm-inline-text identity)
 255     ("application/x-.?tar\\(-.*\\)?" mm-archive-dissect-and-inline identity)
 256     ("application/zip" mm-archive-dissect-and-inline identity)
 257     ("audio/wav" mm-inline-audio
 258      (lambda (handle)
 259        (and (or (featurep 'nas-sound) (featurep 'native-sound))
 260             (device-sound-enabled-p))))
 261     ("audio/au"
 262      mm-inline-audio
 263      (lambda (handle)
 264        (and (or (featurep 'nas-sound) (featurep 'native-sound))
 265             (device-sound-enabled-p))))
 266     ("application/pgp-signature" ignore identity)
 267     ("application/x-pkcs7-signature" ignore identity)
 268     ("application/pkcs7-signature" ignore identity)
 269     ("application/x-pkcs7-mime" ignore identity)
 270     ("application/pkcs7-mime" ignore identity)
 271     ("multipart/alternative" ignore identity)
 272     ("multipart/mixed" ignore identity)
 273     ("multipart/related" ignore identity)
 274     ("image/.*"
 275      mm-inline-image
 276      (lambda (handle)
 277        (and (mm-valid-image-format-p 'imagemagick)
 278             (mm-with-unibyte-buffer
 279               (mm-insert-part handle)
 280               (let ((image
 281                      (ignore-errors
 282                        (if (fboundp 'create-image)
 283                            (create-image (buffer-string) 'imagemagick 'data-p)
 284                          (mm-create-image-xemacs
 285                           (mm-handle-media-subtype handle))))))
 286                 (when image
 287                   (setcar (cdr handle) (list "image/imagemagick"))
 288                   (mm-image-fit-p handle)))))))
 289     ;; Disable audio and image
 290     ("audio/.*" ignore ignore)
 291     ("image/.*" ignore ignore)
 292     ;; Default to displaying as text
 293     (".*" mm-inline-text mm-readable-p))
 294   "Alist of media types/tests saying whether types can be displayed inline."
 295   :type '(repeat (list (regexp :tag "MIME type")
 296                        (function :tag "Display function")
 297                        (function :tag "Display test")))
 298   :group 'mime-display)
 299
 300 (defcustom mm-inlined-types
 301   '("image/.*" "text/.*" "message/delivery-status" "message/rfc822"
 302     "message/partial" "message/external-body" "application/emacs-lisp"
 303     "application/x-emacs-lisp"
 304     "application/pgp-signature" "application/x-pkcs7-signature"
 305     "application/pkcs7-signature" "application/x-pkcs7-mime"
 306     "application/pkcs7-mime"
 307     "application/x-gtar-compressed"
 308     "application/x-tar"
 309     "application/zip"
 310     ;; Mutt still uses this even though it has already been withdrawn.
 311     "application/pgp")
 312   "List of media types that are to be displayed inline.
 313 See also `mm-inline-media-tests', which says how to display a media
 314 type inline."
 315   :type '(repeat regexp)
 316   :group 'mime-display)
 317
 318 (defcustom mm-keep-viewer-alive-types
 319   '("application/postscript" "application/msword" "application/vnd.ms-excel"
 320     "application/pdf" "application/x-dvi")
 321   "List of media types for which the external viewer will not be killed
 322 when selecting a different article."
 323   :version "22.1"
 324   :type '(repeat regexp)
 325   :group 'mime-display)
 326
 327 (defcustom mm-automatic-display
 328   '("text/plain" "text/enriched" "text/richtext" "text/html" "text/x-verbatim"
 329     "text/x-vcard" "image/.*" "message/delivery-status" "multipart/.*"
 330     "message/rfc822" "text/x-patch" "text/dns" "application/pgp-signature"
 331     "application/emacs-lisp" "application/x-emacs-lisp"
 332     "application/x-pkcs7-signature"
 333     "application/pkcs7-signature" "application/x-pkcs7-mime"
 334     "application/pkcs7-mime"
 335     ;; Mutt still uses this even though it has already been withdrawn.
 336     "application/pgp\\'"
 337      "text/x-org")
 338   "A list of MIME types to be displayed automatically."
 339   :type '(repeat regexp)
 340   :group 'mime-display)
 341
 342 (defcustom mm-attachment-override-types '("text/x-vcard"
 343                                           "application/pkcs7-mime"
 344                                           "application/x-pkcs7-mime"
 345                                           "application/pkcs7-signature"
 346                                           "application/x-pkcs7-signature")
 347   "Types to have \"attachment\" ignored if they can be displayed inline."
 348   :type '(repeat regexp)
 349   :group 'mime-display)
 350
 351 (defcustom mm-inline-override-types nil
 352   "Types to be treated as attachments even if they can be displayed inline."
 353   :type '(repeat regexp)
 354   :group 'mime-display)
 355
 356 (defcustom mm-automatic-external-display nil
 357   "List of MIME type regexps that will be displayed externally automatically."
 358   :type '(repeat regexp)
 359   :group 'mime-display)
 360
 361 (defcustom mm-discouraged-alternatives nil
 362   "List of MIME types that are discouraged when viewing multipart/alternative.
 363 Viewing agents are supposed to view the last possible part of a message,
 364 as that is supposed to be the richest.  However, users may prefer other
 365 types instead, and this list says what types are most unwanted.  If,
 366 for instance, text/html parts are very unwanted, and text/richtext are
 367 somewhat unwanted, then the value of this variable should be set
 368 to:
 369
 370  (\"text/html\" \"text/richtext\")
 371
 372 Adding \"image/.*\" might also be useful.  Spammers use it as the
 373 preferred part of multipart/alternative messages.  See also
 374 `gnus-buttonized-mime-types', to which adding \"multipart/alternative\"
 375 enables you to choose manually one of two types those mails include."
 376   :type '(repeat regexp) ;; See `mm-preferred-alternative-precedence'.
 377   :group 'mime-display)
 378
 379 (defcustom mm-tmp-directory
 380   (if (fboundp 'temp-directory)
 381       (temp-directory)
 382     (if (boundp 'temporary-file-directory)
 383         temporary-file-directory
 384       "/tmp/"))
 385   "Where mm will store its temporary files."
 386   :type 'directory
 387   :group 'mime-display)
 388
 389 (defcustom mm-inline-large-images nil
 390   "If t, then all images fit in the buffer.
 391 If 'resize, try to resize the images so they fit."
 392   :type '(radio
 393           (const :tag "Inline large images as they are." t)
 394           (const :tag "Resize large images." resize)
 395           (const :tag "Do not inline large images." nil))
 396   :group 'mime-display)
 397
 398 (defcustom mm-file-name-rewrite-functions
 399   '(mm-file-name-delete-control mm-file-name-delete-gotchas)
 400   "List of functions used for rewriting file names of MIME parts.
 401 Each function takes a file name as input and returns a file name.
 402
 403 Ready-made functions include `mm-file-name-delete-control',
 404 `mm-file-name-delete-gotchas' (you should not remove these two
 405 functions), `mm-file-name-delete-whitespace',
 406 `mm-file-name-trim-whitespace', `mm-file-name-collapse-whitespace',
 407 `mm-file-name-replace-whitespace', `capitalize', `downcase',
 408 `upcase', and `upcase-initials'."
 409   :type '(list (set :inline t
 410                     (const mm-file-name-delete-control)
 411                     (const mm-file-name-delete-gotchas)
 412                     (const mm-file-name-delete-whitespace)
 413                     (const mm-file-name-trim-whitespace)
 414                     (const mm-file-name-collapse-whitespace)
 415                     (const mm-file-name-replace-whitespace)
 416                     (const capitalize)
 417                     (const downcase)
 418                     (const upcase)
 419                     (const upcase-initials)
 420                (repeat :inline t
 421                        :tag "Function"
 422                        function)))
 423   :version "23.1" ;; No Gnus
 424   :group 'mime-display)
 425
 426
 427 (defvar mm-path-name-rewrite-functions nil
 428   "*List of functions for rewriting the full file names of MIME parts.
 429 This is used when viewing parts externally, and is meant for
 430 transforming the absolute name so that non-compliant programs can find
 431 the file where it's saved.
 432
 433 Each function takes a file name as input and returns a file name.")
 434
 435 (defvar mm-file-name-replace-whitespace nil
 436   "String used for replacing whitespace characters; default is `\"_\"'.")
 437
 438 (defcustom mm-default-directory nil
 439   "The default directory where mm will save files.
 440 If not set, `default-directory' will be used."
 441   :type '(choice directory (const :tag "Default" nil))
 442   :group 'mime-display)
 443
 444 (defcustom mm-attachment-file-modes 384
 445   "Set the mode bits of saved attachments to this integer."
 446   :version "22.1"
 447   :type 'integer
 448   :group 'mime-display)
 449
 450 (defcustom mm-external-terminal-program "xterm"
 451   "The program to start an external terminal."
 452   :version "22.1"
 453   :type 'string
 454   :group 'mime-display)
 455
 456 ;;; Internal variables.
 457
 458 (defvar mm-last-shell-command "")
 459 (defvar mm-content-id-alist nil)
 460 (defvar mm-postponed-undisplay-list nil)
 461 (defvar mm-inhibit-auto-detect-attachment nil)
 462
 463 ;; According to RFC2046, in particular, in a digest, the default
 464 ;; Content-Type value for a body part is changed from "text/plain" to
 465 ;; "message/rfc822".
 466 (defvar mm-dissect-default-type "text/plain")
 467
 468 (autoload 'mml2015-verify "mml2015")
 469 (autoload 'mml2015-verify-test "mml2015")
 470 (autoload 'mml-smime-verify "mml-smime")
 471 (autoload 'mml-smime-verify-test "mml-smime")
 472
 473 (defvar mm-verify-function-alist
 474   '(("application/pgp-signature" mml2015-verify "PGP" mml2015-verify-test)
 475     ("application/x-gnus-pgp-signature" mm-uu-pgp-signed-extract-1 "PGP"
 476      mm-uu-pgp-signed-test)
 477     ("application/pkcs7-signature" mml-smime-verify "S/MIME"
 478      mml-smime-verify-test)
 479     ("application/x-pkcs7-signature" mml-smime-verify "S/MIME"
 480      mml-smime-verify-test)))
 481
 482 (defcustom mm-verify-option 'never
 483   "Option of verifying signed parts.
 484 `never', not verify; `always', always verify;
 485 `known', only verify known protocols.  Otherwise, ask user.
 486
 487 When set to `always' or `known', you should add
 488 \"multipart/signed\" to `gnus-buttonized-mime-types' to see
 489 result of the verification."
 490   :version "22.1"
 491   :type '(choice (item always)
 492                  (item never)
 493                  (item :tag "only known protocols" known)
 494                  (item :tag "ask" nil))
 495   :group 'mime-security)
 496
 497 (autoload 'mml2015-decrypt "mml2015")
 498 (autoload 'mml2015-decrypt-test "mml2015")
 499
 500 (defvar mm-decrypt-function-alist
 501   '(("application/pgp-encrypted" mml2015-decrypt "PGP" mml2015-decrypt-test)
 502     ("application/x-gnus-pgp-encrypted" mm-uu-pgp-encrypted-extract-1 "PGP"
 503      mm-uu-pgp-encrypted-test)))
 504
 505 (defcustom mm-decrypt-option nil
 506   "Option of decrypting encrypted parts.
 507 `never', not decrypt; `always', always decrypt;
 508 `known', only decrypt known protocols.  Otherwise, ask user."
 509   :version "22.1"
 510   :type '(choice (item always)
 511                  (item never)
 512                  (item :tag "only known protocols" known)
 513                  (item :tag "ask" nil))
 514   :group 'mime-security)
 515
 516 (defvar mm-viewer-completion-map
 517   (let ((map (make-sparse-keymap 'mm-viewer-completion-map)))
 518     (set-keymap-parent map minibuffer-local-completion-map)
 519     ;; Should we bind other key to minibuffer-complete-word?
 520     (define-key map " " 'self-insert-command)
 521     map)
 522   "Keymap for input viewer with completion.")
 523
 524 (defvar mm-viewer-completion-map
 525   (let ((map (make-sparse-keymap 'mm-viewer-completion-map)))
 526     (set-keymap-parent map minibuffer-local-completion-map)
 527     ;; Should we bind other key to minibuffer-complete-word?
 528     (define-key map " " 'self-insert-command)
 529     map)
 530   "Keymap for input viewer with completion.")
 531
 532 ;;; The functions.
 533
 534 (defun mm-alist-to-plist (alist)
 535   "Convert association list ALIST into the equivalent property-list form.
 536 The plist is returned.  This converts from
 537
 538 \((a . 1) (b . 2) (c . 3))
 539
 540 into
 541
 542 \(a 1 b 2 c 3)
 543
 544 The original alist is not modified.  See also `destructive-alist-to-plist'."
 545   (let (plist)
 546     (while alist
 547       (let ((el (car alist)))
 548         (setq plist (cons (cdr el) (cons (car el) plist))))
 549       (setq alist (cdr alist)))
 550     (nreverse plist)))
 551
 552 (defun mm-keep-viewer-alive-p (handle)
 553   "Say whether external viewer for HANDLE should stay alive."
 554   (let ((types mm-keep-viewer-alive-types)
 555         (type (mm-handle-media-type handle))
 556         ty)
 557     (catch 'found
 558       (while (setq ty (pop types))
 559         (when (string-match ty type)
 560           (throw 'found t))))))
 561
 562 (defun mm-handle-set-external-undisplayer (handle function)
 563   "Set the undisplayer for HANDLE to FUNCTION.
 564 Postpone undisplaying of viewers for types in
 565 `mm-keep-viewer-alive-types'."
 566   (if (mm-keep-viewer-alive-p handle)
 567       (let ((new-handle (copy-sequence handle)))
 568         (mm-handle-set-undisplayer new-handle function)
 569         (mm-handle-set-undisplayer handle nil)
 570         (push new-handle mm-postponed-undisplay-list))
 571     (mm-handle-set-undisplayer handle function)))
 572
 573 (defun mm-destroy-postponed-undisplay-list ()
 574   (when mm-postponed-undisplay-list
 575     (message "Destroying external MIME viewers")
 576     (mm-destroy-parts mm-postponed-undisplay-list)))
 577
 578 (autoload 'message-fetch-field "message")
 579
 580 (defun mm-dissect-buffer (&optional no-strict-mime loose-mime from)
 581   "Dissect the current buffer and return a list of MIME handles.
 582 If NO-STRICT-MIME, don't require the message to have a
 583 MIME-Version header before proceeding."
 584   (save-excursion
 585     (let (ct ctl type subtype cte cd description id result)
 586       (save-restriction
 587         (mail-narrow-to-head)
 588         (when (or no-strict-mime
 589                   loose-mime
 590                   (mail-fetch-field "mime-version"))
 591           (setq ct (mail-fetch-field "content-type")
 592                 ctl (and ct (mail-header-parse-content-type ct))
 593                 cte (mail-fetch-field "content-transfer-encoding")
 594                 cd (or (mail-fetch-field "content-disposition")
 595                        (when (and ctl
 596                                   (eq 'mm-inline-text
 597                                       (cadr (mm-assoc-string-match
 598                                              mm-inline-media-tests
 599                                              (car ctl)))))
 600                          "inline"))
 601                 ;; Newlines in description should be stripped so as
 602                 ;; not to break the MIME tag into two or more lines.
 603                 description (message-fetch-field "content-description")
 604                 id (mail-fetch-field "content-id"))
 605           (unless from
 606             (setq from (mail-fetch-field "from")))
 607           ;; FIXME: In some circumstances, this code is running within
 608           ;; an unibyte macro.  mail-extract-address-components
 609           ;; creates unibyte buffers. This `if', though not a perfect
 610           ;; solution, avoids most of them.
 611           (if from
 612               (setq from (cadr (mail-extract-address-components from))))
 613           (if description
 614               (setq description (mail-decode-encoded-word-string
 615                                  description)))))
 616       (if (or (not ctl)
 617               (not (string-match "/" (car ctl))))
 618           (mm-dissect-singlepart
 619            (list mm-dissect-default-type)
 620            (and cte (intern (downcase (mail-header-strip cte))))
 621            no-strict-mime
 622            (and cd (mail-header-parse-content-disposition cd))
 623            description)
 624         (setq type (split-string (car ctl) "/"))
 625         (setq subtype (cadr type)
 626               type (car type))
 627         (setq
 628          result
 629          (cond
 630           ((equal type "multipart")
 631            (let ((mm-dissect-default-type (if (equal subtype "digest")
 632                                               "message/rfc822"
 633                                             "text/plain"))
 634                  (start (cdr (assq 'start (cdr ctl)))))
 635              (add-text-properties 0 (length (car ctl))
 636                                   (mm-alist-to-plist (cdr ctl)) (car ctl))
 637
 638              ;; what really needs to be done here is a way to link a
 639              ;; MIME handle back to it's parent MIME handle (in a multilevel
 640              ;; MIME article).  That would probably require changing
 641              ;; the mm-handle API so we simply store the multipart buffer
 642              ;; name as a text property of the "multipart/whatever" string.
 643              (add-text-properties 0 (length (car ctl))
 644                                   (list 'buffer (mm-copy-to-buffer)
 645                                         'from from
 646                                         'start start)
 647                                   (car ctl))
 648              (cons (car ctl) (mm-dissect-multipart ctl from))))
 649           (t
 650            (mm-possibly-verify-or-decrypt
 651             (mm-dissect-singlepart
 652              ctl
 653              (and cte (intern (downcase (mail-header-strip cte))))
 654              no-strict-mime
 655              (and cd (mail-header-parse-content-disposition cd))
 656              description id)
 657             ctl from))))
 658         (when id
 659           (when (string-match " *<\\(.*\\)> *" id)
 660             (setq id (match-string 1 id)))
 661           (push (cons id result) mm-content-id-alist))
 662         result))))
 663
 664 (defun mm-dissect-singlepart (ctl cte &optional force cdl description id)
 665   (when (or force
 666             (if (equal "text/plain" (car ctl))
 667                 (assoc 'format ctl)
 668               t))
 669     ;; Guess what the type of application/octet-stream parts should
 670     ;; really be.
 671     (let ((filename (cdr (assq 'filename (cdr cdl)))))
 672       (when (and (not mm-inhibit-auto-detect-attachment)
 673                  (equal (car ctl) "application/octet-stream")
 674                  filename
 675                  (string-match "\\.\\([^.]+\\)$" filename))
 676         (let ((new-type (mailcap-extension-to-mime (match-string 1 filename))))
 677           (when new-type
 678             (setcar ctl new-type)))))
 679     (let ((handle
 680            (mm-make-handle
 681             (mm-copy-to-buffer) ctl cte nil cdl description nil id))
 682           (decoder (assoc (car ctl) (mm-archive-decoders))))
 683       (if (and decoder
 684                ;; Do automatic decoding
 685                (cadr decoder)
 686                (executable-find (caddr decoder)))
 687           (mm-dissect-archive handle)
 688         handle))))
 689
 690 (defun mm-dissect-multipart (ctl from)
 691   (goto-char (point-min))
 692   (let* ((boundary (concat "\n--" (mail-content-type-get ctl 'boundary)))
 693          (close-delimiter (concat (regexp-quote boundary) "--[ \t]*$"))
 694          start parts
 695          (end (save-excursion
 696                 (goto-char (point-max))
 697                 (if (re-search-backward close-delimiter nil t)
 698                     (match-beginning 0)
 699                   (point-max))))
 700          (mm-inhibit-auto-detect-attachment
 701           (equal (car ctl) "multipart/encrypted")))
 702     (setq boundary (concat (regexp-quote boundary) "[ \t]*$"))
 703     (while (and (< (point) end) (re-search-forward boundary end t))
 704       (goto-char (match-beginning 0))
 705       (when start
 706         (save-excursion
 707           (save-restriction
 708             (narrow-to-region start (point))
 709             (setq parts (nconc (list (mm-dissect-buffer t nil from)) parts)))))
 710       (end-of-line 2)
 711       (or (looking-at boundary)
 712           (forward-line 1))
 713       (setq start (point)))
 714     (when (and start (< start end))
 715       (save-excursion
 716         (save-restriction
 717           (narrow-to-region start end)
 718           (setq parts (nconc (list (mm-dissect-buffer t nil from)) parts)))))
 719     (mm-possibly-verify-or-decrypt (nreverse parts) ctl from)))
 720
 721 (defun mm-copy-to-buffer ()
 722   "Copy the contents of the current buffer to a fresh buffer."
 723   (let ((obuf (current-buffer))
 724         (mb (mm-multibyte-p))
 725         beg)
 726     (goto-char (point-min))
 727     (search-forward-regexp "^\n" nil t)
 728     (setq beg (point))
 729     (with-current-buffer
 730           (generate-new-buffer " *mm*")
 731       ;; Preserve the data's unibyteness (for url-insert-file-contents).
 732       (mm-set-buffer-multibyte mb)
 733       (insert-buffer-substring obuf beg)
 734       (current-buffer))))
 735
 736 (defun mm-display-parts (handle &optional no-default)
 737   (if (stringp (car handle))
 738       (mapcar 'mm-display-parts (cdr handle))
 739     (if (bufferp (car handle))
 740         (save-restriction
 741           (narrow-to-region (point) (point))
 742           (mm-display-part handle)
 743           (goto-char (point-max)))
 744       (mapcar 'mm-display-parts handle))))
 745
 746 (autoload 'mailcap-parse-mailcaps "mailcap")
 747 (autoload 'mailcap-mime-info "mailcap")
 748
 749 (defun mm-display-part (handle &optional no-default force)
 750   "Display the MIME part represented by HANDLE.
 751 Returns nil if the part is removed; inline if displayed inline;
 752 external if displayed external."
 753   (save-excursion
 754     (mailcap-parse-mailcaps)
 755     (if (and (not force)
 756              (mm-handle-displayed-p handle))
 757         (mm-remove-part handle)
 758       (let* ((ehandle (if (equal (mm-handle-media-type handle)
 759                                  "message/external-body")
 760                           (progn
 761                             (unless (mm-handle-cache handle)
 762                               (mm-extern-cache-contents handle))
 763                             (mm-handle-cache handle))
 764                         handle))
 765              (type (mm-handle-media-type ehandle))
 766              (method (mailcap-mime-info type))
 767              (filename (or (mail-content-type-get
 768                             (mm-handle-disposition handle) 'filename)
 769                            (mail-content-type-get
 770                             (mm-handle-type handle) 'name)
 771                            "<file>"))
 772              (external mm-enable-external)
 773              (decoder (assoc (car (mm-handle-type handle))
 774                              (mm-archive-decoders))))
 775         (cond
 776          ((and decoder
 777                (executable-find (caddr decoder)))
 778           (mm-archive-dissect-and-inline handle)
 779           'inline)
 780          ((and (mm-inlinable-p ehandle)
 781                (mm-inlined-p ehandle))
 782           (forward-line 1)
 783           (mm-display-inline handle)
 784           'inline)
 785          ((or method
 786               (not no-default))
 787           (if (and (not method)
 788                    (equal "text" (car (split-string type "/"))))
 789               (progn
 790                 (forward-line 1)
 791                 (mm-insert-inline handle (mm-get-part handle))
 792                 'inline)
 793             (setq external
 794                   (and method         ;; If nil, we always use "save".
 795                        (stringp method) ;; 'mailcap-save-binary-file
 796                        (or (eq mm-enable-external t)
 797                            (and (eq mm-enable-external 'ask)
 798                                 (y-or-n-p
 799                                  (concat
 800                                   "Display part (" type
 801                                   ") using external program"
 802                                   ;; Can non-string method ever happen?
 803                                   (if (stringp method)
 804                                       (concat
 805                                        " \"" (format method filename) "\"")
 806                                     "")
 807                                   "? "))))))
 808             (if external
 809                 (mm-display-external
 810                  handle (or method 'mailcap-save-binary-file))
 811               (mm-display-external
 812                handle 'mailcap-save-binary-file)))))))))
 813
 814 (declare-function gnus-configure-windows "gnus-win" (setting &optional force))
 815 (defvar mailcap-mime-extensions)        ; mailcap-mime-info autoloads
 816
 817 (defun mm-display-external (handle method)
 818   "Display HANDLE using METHOD."
 819   (let ((outbuf (current-buffer)))
 820     (mm-with-unibyte-buffer
 821       (if (functionp method)
 822           (let ((cur (current-buffer)))
 823             (if (eq method 'mailcap-save-binary-file)
 824                 (progn
 825                   (set-buffer (generate-new-buffer " *mm*"))
 826                   (setq method nil))
 827               (mm-insert-part handle)
 828               (mm-add-meta-html-tag handle)
 829               (let ((win (get-buffer-window cur t)))
 830                 (when win
 831                   (select-window win)))
 832               (switch-to-buffer (generate-new-buffer " *mm*")))
 833             (buffer-disable-undo)
 834             (mm-set-buffer-file-coding-system mm-binary-coding-system)
 835             (insert-buffer-substring cur)
 836             (goto-char (point-min))
 837             (when method
 838               (message "Viewing with %s" method))
 839             (let ((mm (current-buffer))
 840                   (non-viewer (assq 'non-viewer
 841                                     (mailcap-mime-info
 842                                      (mm-handle-media-type handle) t))))
 843               (unwind-protect
 844                   (if method
 845                       (funcall method)
 846                     (mm-save-part handle))
 847                 (when (and (not non-viewer)
 848                            method)
 849                   (mm-handle-set-undisplayer handle mm)))))
 850         ;; The function is a string to be executed.
 851         (mm-insert-part handle)
 852         (mm-add-meta-html-tag handle)
 853         (let* ((dir (mm-make-temp-file
 854                      (expand-file-name "emm." mm-tmp-directory) 'dir))
 855                (filename (or
 856                           (mail-content-type-get
 857                            (mm-handle-disposition handle) 'filename)
 858                           (mail-content-type-get
 859                            (mm-handle-type handle) 'name)))
 860                (mime-info (mailcap-mime-info
 861                            (mm-handle-media-type handle) t))
 862                (needsterm (or (assoc "needsterm" mime-info)
 863                               (assoc "needsterminal" mime-info)))
 864                (copiousoutput (assoc "copiousoutput" mime-info))
 865                file buffer)
 866           ;; We create a private sub-directory where we store our files.
 867           (set-file-modes dir #o700)
 868           (if filename
 869               (setq file (expand-file-name
 870                           (gnus-map-function mm-file-name-rewrite-functions
 871                                              (file-name-nondirectory filename))
 872                           dir))
 873             ;; Use nametemplate (defined in RFC1524) if it is specified
 874             ;; in mailcap.
 875             (let ((suffix (cdr (assoc "nametemplate" mime-info))))
 876               (if (and suffix
 877                        (string-match "\\`%s\\(\\..+\\)\\'" suffix))
 878                   (setq suffix (match-string 1 suffix))
 879                 ;; Otherwise, use a suffix according to
 880                 ;; `mailcap-mime-extensions'.
 881                 (setq suffix (car (rassoc (mm-handle-media-type handle)
 882                                           mailcap-mime-extensions))))
 883               (setq file (mm-make-temp-file (expand-file-name "mm." dir)
 884                                             nil suffix))))
 885           (let ((coding-system-for-write mm-binary-coding-system))
 886             (write-region (point-min) (point-max) file nil 'nomesg))
 887           ;; The file is deleted after the viewer exists.  If the users edits
 888           ;; the file, changes will be lost.  Set file to read-only to make it
 889           ;; clear.
 890           (set-file-modes file #o400)
 891           (message "Viewing with %s" method)
 892           (cond
 893            (needsterm
 894             (let ((command (mm-mailcap-command
 895                             method file (mm-handle-type handle))))
 896               (unwind-protect
 897                   (if window-system
 898                       (start-process "*display*" nil
 899                                      mm-external-terminal-program
 900                                      "-e" shell-file-name
 901                                      shell-command-switch command)
 902                     (require 'term)
 903                     (require 'gnus-win)
 904                     (set-buffer
 905                      (setq buffer
 906                            (make-term "display"
 907                                       shell-file-name
 908                                       nil
 909                                       shell-command-switch command)))
 910                     (term-mode)
 911                     (term-char-mode)
 912                     (set-process-sentinel
 913                      (get-buffer-process buffer)
 914                      `(lambda (process state)
 915                         (if (eq 'exit (process-status process))
 916                             (gnus-configure-windows
 917                              ',gnus-current-window-configuration))))
 918                     (gnus-configure-windows 'display-term))
 919                 (mm-handle-set-external-undisplayer handle (cons file buffer)))
 920               (message "Displaying %s..." command))
 921             'external)
 922            (copiousoutput
 923             (with-current-buffer outbuf
 924               (forward-line 1)
 925               (mm-insert-inline
 926                handle
 927                (unwind-protect
 928                    (progn
 929                      (call-process shell-file-name nil
 930                                    (setq buffer
 931                                          (generate-new-buffer " *mm*"))
 932                                    nil
 933                                    shell-command-switch
 934                                    (mm-mailcap-command
 935                                     method file (mm-handle-type handle)))
 936                      (if (buffer-live-p buffer)
 937                          (with-current-buffer buffer
 938                            (buffer-string))))
 939                  (progn
 940                    (ignore-errors (delete-file file))
 941                    (ignore-errors (delete-directory
 942                                    (file-name-directory file)))
 943                    (ignore-errors (kill-buffer buffer))))))
 944             'inline)
 945            (t
 946             ;; Deleting the temp file should be postponed for some wrappers,
 947             ;; shell scripts, and so on, which might exit right after having
 948             ;; started a viewer command as a background job.
 949             (let ((command (mm-mailcap-command
 950                             method file (mm-handle-type handle))))
 951               (unwind-protect
 952                   (progn
 953                     (start-process "*display*"
 954                                    (setq buffer
 955                                          (generate-new-buffer " *mm*"))
 956                                    shell-file-name
 957                                    shell-command-switch command)
 958                     (set-process-sentinel
 959                      (get-buffer-process buffer)
 960                      (lexical-let ((outbuf outbuf)
 961                                    (file file)
 962                                    (buffer buffer)
 963                                    (command command)
 964                                    (handle handle))
 965                        (run-at-time
 966                         30.0 nil
 967                         (lambda ()
 968                           (ignore-errors
 969                             (delete-file file))
 970                           (ignore-errors
 971                             (delete-directory (file-name-directory file)))))
 972                        (lambda (process state)
 973                          (when (eq (process-status process) 'exit)
 974                            (condition-case nil
 975                                (delete-file file)
 976                              (error))
 977                            (condition-case nil
 978                                (delete-directory (file-name-directory file))
 979                              (error))
 980                            (when (buffer-live-p outbuf)
 981                              (with-current-buffer outbuf
 982                                (let ((buffer-read-only nil)
 983                                      (point (point)))
 984                                  (forward-line 2)
 985                                  (mm-insert-inline
 986                                   handle (with-current-buffer buffer
 987                                            (buffer-string)))
 988                                  (goto-char point))))
 989                            (when (buffer-live-p buffer)
 990                              (kill-buffer buffer)))
 991                          (message "Displaying %s...done" command)))))
 992                 (mm-handle-set-external-undisplayer
 993                  handle (cons file buffer)))
 994               (message "Displaying %s..." command))
 995             'external)))))))
 996
 997 (defun mm-mailcap-command (method file type-list)
 998   (let ((ctl (cdr type-list))
 999         (beg 0)
1000         (uses-stdin t)
1001         out sub total)
1002     (while (string-match "%{\\([^}]+\\)}\\|'%s'\\|\"%s\"\\|%s\\|%t\\|%%"
1003                          method beg)
1004       (push (substring method beg (match-beginning 0)) out)
1005       (setq beg (match-end 0)
1006             total (match-string 0 method)
1007             sub (match-string 1 method))
1008       (cond
1009        ((string= total "%%")
1010         (push "%" out))
1011        ((or (string= total "%s")
1012             ;; We do our own quoting.
1013             (string= total "'%s'")
1014             (string= total "\"%s\""))
1015         (setq uses-stdin nil)
1016         (push (shell-quote-argument
1017                (gnus-map-function mm-path-name-rewrite-functions file)) out))
1018        ((string= total "%t")
1019         (push (shell-quote-argument (car type-list)) out))
1020        (t
1021         (push (shell-quote-argument (or (cdr (assq (intern sub) ctl)) "")) out))))
1022     (push (substring method beg (length method)) out)
1023     (when uses-stdin
1024       (push "<" out)
1025       (push (shell-quote-argument
1026              (gnus-map-function mm-path-name-rewrite-functions file))
1027             out))
1028     (mapconcat 'identity (nreverse out) "")))
1029
1030 (defun mm-remove-parts (handles)
1031   "Remove the displayed MIME parts represented by HANDLES."
1032   (if (and (listp handles)
1033            (bufferp (car handles)))
1034       (mm-remove-part handles)
1035     (let (handle)
1036       (while (setq handle (pop handles))
1037         (cond
1038          ((stringp handle)
1039           (when (buffer-live-p (get-text-property 0 'buffer handle))
1040             (kill-buffer (get-text-property 0 'buffer handle))))
1041          ((and (listp handle)
1042                (stringp (car handle)))
1043           (mm-remove-parts (cdr handle)))
1044          (t
1045           (mm-remove-part handle)))))))
1046
1047 (defun mm-destroy-parts (handles)
1048   "Remove the displayed MIME parts represented by HANDLES."
1049   (if (and (listp handles)
1050            (bufferp (car handles)))
1051       (mm-destroy-part handles)
1052     (let (handle)
1053       (while (setq handle (pop handles))
1054         (cond
1055          ((stringp handle)
1056           (when (buffer-live-p (get-text-property 0 'buffer handle))
1057             (kill-buffer (get-text-property 0 'buffer handle))))
1058          ((and (listp handle)
1059                (stringp (car handle)))
1060           (mm-destroy-parts handle))
1061          (t
1062           (mm-destroy-part handle)))))))
1063
1064 (defun mm-remove-part (handle)
1065   "Remove the displayed MIME part represented by HANDLE."
1066   (when (listp handle)
1067     (let ((object (mm-handle-undisplayer handle)))
1068       (ignore-errors
1069         (cond
1070          ;; Internally displayed part.
1071          ((mm-annotationp object)
1072           (if (featurep 'xemacs)
1073               (delete-annotation object)))
1074          ((or (functionp object)
1075               (and (listp object)
1076                    (eq (car object) 'lambda)))
1077           (funcall object))
1078          ;; Externally displayed part.
1079          ((consp object)
1080           (condition-case ()
1081               (while (get-buffer-process (cdr object))
1082                 (interrupt-process (get-buffer-process (cdr object)))
1083                 (message "Waiting for external displayer to die...")
1084                 (sit-for 1))
1085             (quit)
1086             (error))
1087           (ignore-errors (and (cdr object) (kill-buffer (cdr object))))
1088           (message "Waiting for external displayer to die...done")
1089           (ignore-errors (delete-file (car object)))
1090           (ignore-errors (delete-directory (file-name-directory
1091                                             (car object)))))
1092          ((bufferp object)
1093           (when (buffer-live-p object)
1094             (kill-buffer object)))))
1095       (mm-handle-set-undisplayer handle nil))))
1096
1097 (defun mm-display-inline (handle)
1098   (let* ((type (mm-handle-media-type handle))
1099          (function (cadr (mm-assoc-string-match mm-inline-media-tests type))))
1100     (funcall function handle)
1101     (goto-char (point-min))))
1102
1103 (defun mm-assoc-string-match (alist type)
1104   (dolist (elem alist)
1105     (when (string-match (car elem) type)
1106       (return elem))))
1107
1108 (defun mm-automatic-display-p (handle)
1109   "Say whether the user wants HANDLE to be displayed automatically."
1110   (let ((methods mm-automatic-display)
1111         (type (mm-handle-media-type handle))
1112         method result)
1113     (while (setq method (pop methods))
1114       (when (and (not (mm-inline-override-p handle))
1115                  (string-match method type))
1116         (setq result t
1117               methods nil)))
1118     result))
1119
1120 (defun mm-inlinable-p (handle &optional type)
1121   "Say whether HANDLE can be displayed inline.
1122 TYPE is the mime-type of the object; it defaults to the one given
1123 in HANDLE."
1124   (unless type (setq type (mm-handle-media-type handle)))
1125   (let ((alist mm-inline-media-tests)
1126         test)
1127     (while alist
1128       (when (string-match (caar alist) type)
1129         (setq test (caddar alist)
1130               alist nil)
1131         (setq test (funcall test handle)))
1132       (pop alist))
1133     test))
1134
1135 (defun mm-inlined-p (handle)
1136   "Say whether the user wants HANDLE to be displayed inline."
1137   (let ((methods mm-inlined-types)
1138         (type (mm-handle-media-type handle))
1139         method result)
1140     (while (setq method (pop methods))
1141       (when (and (not (mm-inline-override-p handle))
1142                  (string-match method type))
1143         (setq result t
1144               methods nil)))
1145     result))
1146
1147 (defun mm-attachment-override-p (handle)
1148   "Say whether HANDLE should have attachment behavior overridden."
1149   (let ((types mm-attachment-override-types)
1150         (type (mm-handle-media-type handle))
1151         ty)
1152     (catch 'found
1153       (while (setq ty (pop types))
1154         (when (and (string-match ty type)
1155                    (mm-inlinable-p handle))
1156           (throw 'found t))))))
1157
1158 (defun mm-inline-override-p (handle)
1159   "Say whether HANDLE should have inline behavior overridden."
1160   (let ((types mm-inline-override-types)
1161         (type (mm-handle-media-type handle))
1162         ty)
1163     (catch 'found
1164       (while (setq ty (pop types))
1165         (when (string-match ty type)
1166           (throw 'found t))))))
1167
1168 (defun mm-automatic-external-display-p (type)
1169   "Return the user-defined method for TYPE."
1170   (let ((methods mm-automatic-external-display)
1171         method result)
1172     (while (setq method (pop methods))
1173       (when (string-match method type)
1174         (setq result t
1175               methods nil)))
1176     result))
1177
1178 (defun mm-destroy-part (handle)
1179   "Destroy the data structures connected to HANDLE."
1180   (when (listp handle)
1181     (mm-remove-part handle)
1182     (when (buffer-live-p (mm-handle-buffer handle))
1183       (kill-buffer (mm-handle-buffer handle)))))
1184
1185 (defun mm-handle-displayed-p (handle)
1186   "Say whether HANDLE is displayed or not."
1187   (mm-handle-undisplayer handle))
1188
1189 ;;;
1190 ;;; Functions for outputting parts
1191 ;;;
1192
1193 (defmacro mm-with-part (handle &rest forms)
1194   "Run FORMS in the temp buffer containing the contents of HANDLE."
1195   ;; The handle-buffer's content is a sequence of bytes, not a sequence of
1196   ;; chars, so the buffer should be unibyte.  It may happen that the
1197   ;; handle-buffer is multibyte for some reason, in which case now is a good
1198   ;; time to adjust it, since we know at this point that it should
1199   ;; be unibyte.
1200   `(let* ((handle ,handle))
1201      (when (and (mm-handle-buffer handle)
1202                 (buffer-name (mm-handle-buffer handle)))
1203        (with-temp-buffer
1204          (mm-disable-multibyte)
1205          (insert-buffer-substring (mm-handle-buffer handle))
1206          (mm-decode-content-transfer-encoding
1207           (mm-handle-encoding handle)
1208           (mm-handle-media-type handle))
1209          ,@forms))))
1210 (put 'mm-with-part 'lisp-indent-function 1)
1211 (put 'mm-with-part 'edebug-form-spec '(body))
1212
1213 (defun mm-get-part (handle &optional no-cache)
1214   "Return the contents of HANDLE as a string.
1215 If NO-CACHE is non-nil, cached contents of a message/external-body part
1216 are ignored."
1217   (if (and (not no-cache)
1218            (equal (mm-handle-media-type handle) "message/external-body"))
1219       (progn
1220         (unless (mm-handle-cache handle)
1221           (mm-extern-cache-contents handle))
1222         (with-current-buffer (mm-handle-buffer (mm-handle-cache handle))
1223           (buffer-string)))
1224     (mm-with-part handle
1225       (buffer-string))))
1226
1227 (defun mm-insert-part (handle &optional no-cache)
1228   "Insert the contents of HANDLE in the current buffer.
1229 If NO-CACHE is non-nil, cached contents of a message/external-body part
1230 are ignored."
1231   (let ((text (cond ((eq (mail-content-type-get (mm-handle-type handle)
1232                                                 'charset)
1233                          'gnus-decoded)
1234                      (with-current-buffer (mm-handle-buffer handle)
1235                        (buffer-string)))
1236                     ((mm-multibyte-p)
1237                      (mm-string-to-multibyte (mm-get-part handle no-cache)))
1238                     (t
1239                      (mm-get-part handle no-cache)))))
1240     (save-restriction
1241       (widen)
1242       (goto-char
1243        (prog1
1244            (point)
1245          (if (and (eq (get-char-property (max (point-min) (1- (point))) 'face)
1246                       'mm-uu-extract)
1247                   (eq (get-char-property 0 'face text) 'mm-uu-extract))
1248              ;; Separate the extracted parts that have the same faces.
1249              (insert "\n" text)
1250            (insert text)))))))
1251
1252 (defun mm-file-name-delete-whitespace (file-name)
1253   "Remove all whitespace characters from FILE-NAME."
1254   (while (string-match "\\s-+" file-name)
1255     (setq file-name (replace-match "" t t file-name)))
1256   file-name)
1257
1258 (defun mm-file-name-trim-whitespace (file-name)
1259   "Remove leading and trailing whitespace characters from FILE-NAME."
1260   (when (string-match "\\`\\s-+" file-name)
1261     (setq file-name (substring file-name (match-end 0))))
1262   (when (string-match "\\s-+\\'" file-name)
1263     (setq file-name (substring file-name 0 (match-beginning 0))))
1264   file-name)
1265
1266 (defun mm-file-name-collapse-whitespace (file-name)
1267   "Collapse multiple whitespace characters in FILE-NAME."
1268   (while (string-match "\\s-\\s-+" file-name)
1269     (setq file-name (replace-match " " t t file-name)))
1270   file-name)
1271
1272 (defun mm-file-name-replace-whitespace (file-name)
1273   "Replace whitespace characters in FILE-NAME with underscores.
1274 Set the option `mm-file-name-replace-whitespace' to any other
1275 string if you do not like underscores."
1276   (let ((s (or mm-file-name-replace-whitespace "_")))
1277     (while (string-match "\\s-" file-name)
1278       (setq file-name (replace-match s t t file-name))))
1279   file-name)
1280
1281 (defun mm-file-name-delete-control (filename)
1282   "Delete control characters from FILENAME."
1283   (gnus-replace-in-string filename "[\x00-\x1f\x7f]" ""))
1284
1285 (defun mm-file-name-delete-gotchas (filename)
1286   "Delete shell gotchas from FILENAME."
1287   (setq filename (gnus-replace-in-string filename "[<>|]" ""))
1288   (gnus-replace-in-string filename "^[.-]+" ""))
1289
1290 (defun mm-save-part (handle &optional prompt)
1291   "Write HANDLE to a file.
1292 PROMPT overrides the default one used to ask user for a file name."
1293   (let ((filename (or (mail-content-type-get
1294                        (mm-handle-disposition handle) 'filename)
1295                       (mail-content-type-get
1296                        (mm-handle-type handle) 'name)))
1297         file)
1298     (when filename
1299       (setq filename (gnus-map-function mm-file-name-rewrite-functions
1300                                         (file-name-nondirectory filename))))
1301     (setq file
1302           (read-file-name
1303            (or prompt
1304                (format "Save MIME part to (default %s): "
1305                        (or filename "")))
1306            (or mm-default-directory default-directory)
1307            (expand-file-name (or filename "")
1308                              (or mm-default-directory default-directory))))
1309     (if (file-directory-p file)
1310         (setq file (expand-file-name filename file))
1311       (setq file (expand-file-name
1312                   file (or mm-default-directory default-directory))))
1313     (setq mm-default-directory (file-name-directory file))
1314     (and (or (not (file-exists-p file))
1315              (yes-or-no-p (format "File %s already exists; overwrite? "
1316                                   file)))
1317          (progn
1318            (mm-save-part-to-file handle file)
1319            file))))
1320
1321 (defun mm-add-meta-html-tag (handle &optional charset force-charset)
1322   "Add meta html tag to specify CHARSET of HANDLE in the current buffer.
1323 CHARSET defaults to the one HANDLE specifies.  Existing meta tag that
1324 specifies charset will not be modified unless FORCE-CHARSET is non-nil.
1325 Return t if meta tag is added or replaced."
1326   (when (equal (mm-handle-media-type handle) "text/html")
1327     (when (or charset
1328               (setq charset (mail-content-type-get (mm-handle-type handle)
1329                                                    'charset)))
1330       (setq charset (format "\
1331 <meta http-equiv=\"Content-Type\" content=\"text/html; charset=%s\">" charset))
1332       (let ((case-fold-search t))
1333         (goto-char (point-min))
1334         (if (re-search-forward "\
1335 <meta\\s-+http-equiv=[\"']?content-type[\"']?\\s-+content=[\"']\
1336 text/\\(\\sw+\\)\\(?:\;\\s-*charset=\\(.+\\)\\)?[\"'][^>]*>" nil t)
1337             (if (and (not force-charset)
1338                      (match-beginning 2)
1339                      (string-match "\\`html\\'" (match-string 1)))
1340                 ;; Don't modify existing meta tag.
1341                 nil
1342               ;; Replace it with the one specifying charset.
1343               (replace-match charset)
1344               t)
1345           (if (re-search-forward "<head>\\s-*" nil t)
1346               (insert charset "\n")
1347             (re-search-forward "<html\\(?:\\s-+[^>]+\\|\\s-*\\)>\\s-*" nil t)
1348             (insert "<head>\n" charset "\n</head>\n"))
1349           t)))))
1350
1351 (defun mm-save-part-to-file (handle file)
1352   (mm-with-unibyte-buffer
1353     (mm-insert-part handle)
1354     (mm-add-meta-html-tag handle)
1355     (let ((current-file-modes (default-file-modes)))
1356       (set-default-file-modes mm-attachment-file-modes)
1357       (unwind-protect
1358           ;; Don't re-compress .gz & al.  Arguably we should make
1359           ;; `file-name-handler-alist' nil, but that would chop
1360           ;; ange-ftp, which is reasonable to use here.
1361           (mm-write-region (point-min) (point-max) file nil nil nil 'binary t)
1362         (set-default-file-modes current-file-modes)))))
1363
1364 (defun mm-pipe-part (handle &optional cmd)
1365   "Pipe HANDLE to a process.
1366 Use CMD as the process."
1367   (let ((name (mail-content-type-get (mm-handle-type handle) 'name))
1368         (command (or cmd
1369                      (gnus-read-shell-command
1370                       "Shell command on MIME part: " mm-last-shell-command))))
1371     (mm-with-unibyte-buffer
1372       (mm-insert-part handle)
1373       (mm-add-meta-html-tag handle)
1374       (let ((coding-system-for-write 'binary))
1375         (shell-command-on-region (point-min) (point-max) command nil)))))
1376
1377 (autoload 'gnus-completing-read "gnus-util")
1378
1379 (defun mm-interactively-view-part (handle)
1380   "Display HANDLE using METHOD."
1381   (let* ((type (mm-handle-media-type handle))
1382          (methods
1383           (mapcar (lambda (i) (cdr (assoc 'viewer i)))
1384                   (mailcap-mime-info type 'all)))
1385          (method (let ((minibuffer-local-completion-map
1386                         mm-viewer-completion-map))
1387                    (completing-read "Viewer: " methods))))
1388     (when (string= method "")
1389       (error "No method given"))
1390     (if (string-match "^[^% \t]+$" method)
1391         (setq method (concat method " %s")))
1392     (mm-display-external handle method)))
1393
1394 (defun mm-preferred-alternative (handles &optional preferred)
1395   "Say which of HANDLES are preferred."
1396   (let ((prec (if preferred (list preferred)
1397                 (mm-preferred-alternative-precedence handles)))
1398         p h result type handle)
1399     (while (setq p (pop prec))
1400       (setq h handles)
1401       (while h
1402         (setq handle (car h))
1403         (setq type (mm-handle-media-type handle))
1404         (when (and (equal p type)
1405                    (mm-automatic-display-p handle)
1406                    (or (stringp (car handle))
1407                        (not (mm-handle-disposition handle))
1408                        (equal (car (mm-handle-disposition handle))
1409                               "inline")))
1410           (setq result handle
1411                 h nil
1412                 prec nil))
1413         (pop h)))
1414     result))
1415
1416 (defun mm-preferred-alternative-precedence (handles)
1417   "Return the precedence based on HANDLES and `mm-discouraged-alternatives'."
1418   (setq handles (reverse handles))
1419   (dolist (disc (reverse mm-discouraged-alternatives))
1420     (dolist (handle (copy-sequence handles))
1421       (when (string-match disc (mm-handle-media-type handle))
1422         (setq handles (nconc (delete handle handles) (list handle))))))
1423   ;; Remove empty parts.
1424   (dolist (handle (copy-sequence handles))
1425     (when (and (bufferp (mm-handle-buffer handle))
1426                (not (with-current-buffer (mm-handle-buffer handle)
1427                       (goto-char (point-min))
1428                       (re-search-forward "[^ \t\n]" nil t))))
1429       (setq handles (nconc (delete handle handles) (list handle)))))
1430   (mapcar #'mm-handle-media-type handles))
1431
1432 (defun mm-get-content-id (id)
1433   "Return the handle(s) referred to by ID."
1434   (cdr (assoc id mm-content-id-alist)))
1435
1436 (defconst mm-image-type-regexps
1437   '(("/\\*.*XPM.\\*/" . xpm)
1438     ("P[1-6]" . pbm)
1439     ("GIF8" . gif)
1440     ("\377\330" . jpeg)
1441     ("\211PNG\r\n" . png)
1442     ("#define" . xbm)
1443     ("\\(MM\0\\*\\)\\|\\(II\\*\0\\)" . tiff)
1444     ("%!PS" . postscript))
1445   "Alist of (REGEXP . IMAGE-TYPE) pairs used to auto-detect image types.
1446 When the first bytes of an image file match REGEXP, it is assumed to
1447 be of image type IMAGE-TYPE.")
1448
1449 ;; Steal from image.el. image-type-from-data suffers multi-line matching bug.
1450 (defun mm-image-type-from-buffer ()
1451   "Determine the image type from data in the current buffer.
1452 Value is a symbol specifying the image type or nil if type cannot
1453 be determined."
1454   (let ((types mm-image-type-regexps)
1455         type)
1456     (goto-char (point-min))
1457     (while (and types (null type))
1458       (let ((regexp (car (car types)))
1459             (image-type (cdr (car types))))
1460         (when (looking-at regexp)
1461           (setq type image-type))
1462         (setq types (cdr types))))
1463     type))
1464
1465 (defun mm-get-image (handle)
1466   "Return an image instance based on HANDLE."
1467   (let ((type (mm-handle-media-subtype handle))
1468         spec)
1469     ;; Allow some common translations.
1470     (setq type
1471           (cond
1472            ((equal type "x-pixmap")
1473             "xpm")
1474            ((equal type "x-xbitmap")
1475             "xbm")
1476            ((equal type "x-portable-bitmap")
1477             "pbm")
1478            (t type)))
1479     (or (mm-handle-cache handle)
1480         (mm-with-unibyte-buffer
1481           (mm-insert-part handle)
1482           (prog1
1483               (setq spec
1484                     (ignore-errors
1485                       ;; Avoid testing `make-glyph' since W3 may define
1486                       ;; a bogus version of it.
1487                       (if (fboundp 'create-image)
1488                           (create-image (buffer-string)
1489                                         (or (mm-image-type-from-buffer)
1490                                             (intern type))
1491                                         'data-p)
1492                         (mm-create-image-xemacs type))))
1493             (mm-handle-set-cache handle spec))))))
1494
1495 (defun mm-create-image-xemacs (type)
1496   (when (featurep 'xemacs)
1497     (cond
1498      ((equal type "xbm")
1499       ;; xbm images require special handling, since
1500       ;; the only way to create glyphs from these
1501       ;; (without a ton of work) is to write them
1502       ;; out to a file, and then create a file
1503       ;; specifier.
1504       (let ((file (mm-make-temp-file
1505                    (expand-file-name "emm" mm-tmp-directory)
1506                    nil ".xbm")))
1507         (unwind-protect
1508             (progn
1509               (write-region (point-min) (point-max) file)
1510               (make-glyph (list (cons 'x file))))
1511           (ignore-errors
1512             (delete-file file)))))
1513      (t
1514       (make-glyph
1515        (vector
1516         (or (mm-image-type-from-buffer)
1517             (intern type))
1518         :data (buffer-string)))))))
1519
1520 (declare-function image-size "image.c" (spec &optional pixels frame))
1521
1522 (defun mm-image-fit-p (handle)
1523   "Say whether the image in HANDLE will fit the current window."
1524   (let ((image (mm-get-image handle)))
1525     (or (not image)
1526         (if (featurep 'xemacs)
1527             ;; XEmacs's glyphs can actually tell us about their width, so
1528             ;; let's be nice and smart about them.
1529             (or mm-inline-large-images
1530                 (and (<= (glyph-width image) (window-pixel-width))
1531                      (<= (glyph-height image) (window-pixel-height))))
1532           (let* ((size (image-size image))
1533                  (w (car size))
1534                  (h (cdr size)))
1535             (or mm-inline-large-images
1536                 (and (<= h (1- (window-height))) ; Don't include mode line.
1537                      (<= w (window-width)))))))))
1538
1539 (defun mm-valid-image-format-p (format)
1540   "Say whether FORMAT can be displayed natively by Emacs."
1541   (cond
1542    ;; Handle XEmacs
1543    ((fboundp 'valid-image-instantiator-format-p)
1544     (valid-image-instantiator-format-p format))
1545    ;; Handle Emacs
1546    ((fboundp 'image-type-available-p)
1547     (and (display-graphic-p)
1548          (image-type-available-p format)))
1549    ;; Nobody else can do images yet.
1550    (t
1551     nil)))
1552
1553 (defun mm-valid-and-fit-image-p (format handle)
1554   "Say whether FORMAT can be displayed natively and HANDLE fits the window."
1555   (and (mm-valid-image-format-p format)
1556        (mm-image-fit-p handle)))
1557
1558 (defun mm-find-part-by-type (handles type &optional notp recursive)
1559   "Search in HANDLES for part with TYPE.
1560 If NOTP, returns first non-matching part.
1561 If RECURSIVE, search recursively."
1562   (let (handle)
1563     (while handles
1564       (if (and recursive (stringp (caar handles)))
1565           (if (setq handle (mm-find-part-by-type (cdar handles) type
1566                                                  notp recursive))
1567               (setq handles nil))
1568         (if (if notp
1569                 (not (equal (mm-handle-media-type (car handles)) type))
1570               (equal (mm-handle-media-type (car handles)) type))
1571             (setq handle (car handles)
1572                   handles nil)))
1573       (setq handles (cdr handles)))
1574     handle))
1575
1576 (defun mm-find-raw-part-by-type (ctl type &optional notp)
1577   (goto-char (point-min))
1578   (let* ((boundary (concat "--" (mm-handle-multipart-ctl-parameter ctl
1579                                                                    'boundary)))
1580          (close-delimiter (concat "^" (regexp-quote boundary) "--[ \t]*$"))
1581          start
1582          (end (save-excursion
1583                 (goto-char (point-max))
1584                 (if (re-search-backward close-delimiter nil t)
1585                     (match-beginning 0)
1586                   (point-max))))
1587          result)
1588     (setq boundary (concat "^" (regexp-quote boundary) "[ \t]*$"))
1589     (while (and (not result)
1590                 (re-search-forward boundary end t))
1591       (goto-char (match-beginning 0))
1592       (when start
1593         (save-excursion
1594           (save-restriction
1595             (narrow-to-region start (1- (point)))
1596             (when (let* ((ct (mail-fetch-field "content-type"))
1597                          (ctl (and ct (mail-header-parse-content-type ct))))
1598                     (if notp
1599                         (not (equal (car ctl) type))
1600                       (equal (car ctl) type)))
1601               (setq result (buffer-string))))))
1602       (forward-line 1)
1603       (setq start (point)))
1604     (when (and (not result) start)
1605       (save-excursion
1606         (save-restriction
1607           (narrow-to-region start end)
1608           (when (let* ((ct (mail-fetch-field "content-type"))
1609                        (ctl (and ct (mail-header-parse-content-type ct))))
1610                   (if notp
1611                       (not (equal (car ctl) type))
1612                     (equal (car ctl) type)))
1613             (setq result (buffer-string))))))
1614     result))
1615
1616 (defvar mm-security-handle nil)
1617
1618 (defsubst mm-set-handle-multipart-parameter (handle parameter value)
1619   ;; HANDLE could be a CTL.
1620   (when handle
1621     (put-text-property 0 (length (car handle)) parameter value
1622                        (car handle))))
1623
1624 (autoload 'mm-view-pkcs7 "mm-view")
1625
1626 (defun mm-possibly-verify-or-decrypt (parts ctl &optional from)
1627   (let ((type (car ctl))
1628         (subtype (cadr (split-string (car ctl) "/")))
1629         (mm-security-handle ctl) ;; (car CTL) is the type.
1630         protocol func functest)
1631     (cond
1632      ((or (equal type "application/x-pkcs7-mime")
1633           (equal type "application/pkcs7-mime"))
1634       (with-temp-buffer
1635         (when (and (cond
1636                     ((eq mm-decrypt-option 'never) nil)
1637                     ((eq mm-decrypt-option 'always) t)
1638                     ((eq mm-decrypt-option 'known) t)
1639                     (t (y-or-n-p
1640                         (format "Decrypt (S/MIME) part? "))))
1641                    (mm-view-pkcs7 parts from))
1642           (setq parts (mm-dissect-buffer t)))))
1643      ((equal subtype "signed")
1644       (unless (and (setq protocol
1645                          (mm-handle-multipart-ctl-parameter ctl 'protocol))
1646                    (not (equal protocol "multipart/mixed")))
1647         ;; The message is broken or draft-ietf-openpgp-multsig-01.
1648         (let ((protocols mm-verify-function-alist))
1649           (while protocols
1650             (if (and (or (not (setq functest (nth 3 (car protocols))))
1651                          (funcall functest parts ctl))
1652                      (mm-find-part-by-type parts (caar protocols) nil t))
1653                 (setq protocol (caar protocols)
1654                       protocols nil)
1655               (setq protocols (cdr protocols))))))
1656       (setq func (nth 1 (assoc protocol mm-verify-function-alist)))
1657       (when (cond
1658              ((eq mm-verify-option 'never) nil)
1659              ((eq mm-verify-option 'always) t)
1660              ((eq mm-verify-option 'known)
1661               (and func
1662                    (or (not (setq functest
1663                                   (nth 3 (assoc protocol
1664                                                 mm-verify-function-alist))))
1665                        (funcall functest parts ctl))))
1666              (t
1667               (y-or-n-p
1668                (format "Verify signed (%s) part? "
1669                        (or (nth 2 (assoc protocol mm-verify-function-alist))
1670                            (format "protocol=%s" protocol))))))
1671         (save-excursion
1672           (if func
1673               (setq parts (funcall func parts ctl))
1674             (mm-set-handle-multipart-parameter
1675              mm-security-handle 'gnus-details
1676              (format "Unknown sign protocol (%s)" protocol))))))
1677      ((equal subtype "encrypted")
1678       (unless (setq protocol
1679                     (mm-handle-multipart-ctl-parameter ctl 'protocol))
1680         ;; The message is broken.
1681         (let ((parts parts))
1682           (while parts
1683             (if (assoc (mm-handle-media-type (car parts))
1684                        mm-decrypt-function-alist)
1685                 (setq protocol (mm-handle-media-type (car parts))
1686                       parts nil)
1687               (setq parts (cdr parts))))))
1688       (setq func (nth 1 (assoc protocol mm-decrypt-function-alist)))
1689       (when (cond
1690              ((eq mm-decrypt-option 'never) nil)
1691              ((eq mm-decrypt-option 'always) t)
1692              ((eq mm-decrypt-option 'known)
1693               (and func
1694                    (or (not (setq functest
1695                                   (nth 3 (assoc protocol
1696                                                 mm-decrypt-function-alist))))
1697                        (funcall functest parts ctl))))
1698              (t
1699               (y-or-n-p
1700                (format "Decrypt (%s) part? "
1701                        (or (nth 2 (assoc protocol mm-decrypt-function-alist))
1702                            (format "protocol=%s" protocol))))))
1703         (save-excursion
1704           (if func
1705               (setq parts (funcall func parts ctl))
1706             (mm-set-handle-multipart-parameter
1707              mm-security-handle 'gnus-details
1708              (format "Unknown encrypt protocol (%s)" protocol))))))
1709      (t nil))
1710     parts))
1711
1712 (defun mm-multiple-handles (handles)
1713   (and (listp handles)
1714        (> (length handles) 1)
1715        (or (listp (car handles))
1716            (stringp (car handles)))))
1717
1718 (defun mm-complicated-handles (handles)
1719   (and (listp (car handles))
1720        (> (length handles) 1)))
1721
1722 (defun mm-merge-handles (handles1 handles2)
1723   (append
1724    (if (listp (car handles1))
1725        handles1
1726      (list handles1))
1727    (if (listp (car handles2))
1728        handles2
1729      (list handles2))))
1730
1731 (defun mm-readable-p (handle)
1732   "Say whether the content of HANDLE is readable."
1733   (and (< (with-current-buffer (mm-handle-buffer handle)
1734             (buffer-size)) 10000)
1735        (mm-with-unibyte-buffer
1736          (mm-insert-part handle)
1737          (and (eq (mm-body-7-or-8) '7bit)
1738               (not (mm-long-lines-p 76))))))
1739
1740 (declare-function libxml-parse-html-region "xml.c"
1741                   (start end &optional base-url))
1742 (declare-function shr-insert-document "shr" (dom))
1743 (defvar shr-blocked-images)
1744 (defvar gnus-inhibit-images)
1745 (autoload 'gnus-blocked-images "gnus-art")
1746
1747 (defun mm-shr (handle)
1748   ;; Require since we bind its variables.
1749   (require 'shr)
1750   (let ((article-buffer (current-buffer))
1751         (shr-content-function (lambda (id)
1752                                 (let ((handle (mm-get-content-id id)))
1753                                   (when handle
1754                                     (mm-with-part handle
1755                                       (buffer-string))))))
1756         shr-inhibit-images shr-blocked-images charset char)
1757     (if (and (boundp 'gnus-summary-buffer)
1758              (bufferp gnus-summary-buffer)
1759              (buffer-name gnus-summary-buffer))
1760         (with-current-buffer gnus-summary-buffer
1761           (setq shr-inhibit-images gnus-inhibit-images
1762                 shr-blocked-images (gnus-blocked-images)))
1763       (setq shr-inhibit-images gnus-inhibit-images
1764             shr-blocked-images (gnus-blocked-images)))
1765     (unless handle
1766       (setq handle (mm-dissect-buffer t)))
1767     (setq charset (mail-content-type-get (mm-handle-type handle) 'charset))
1768     (save-restriction
1769       (narrow-to-region (point) (point))
1770       (shr-insert-document
1771        (mm-with-part handle
1772          (insert (prog1
1773                      (if (and charset
1774                               (setq charset
1775                                     (mm-charset-to-coding-system charset
1776                                                                  nil t))
1777                               (not (eq charset 'ascii)))
1778                          (mm-decode-coding-string (buffer-string) charset)
1779                        (mm-string-as-multibyte (buffer-string)))
1780                    (erase-buffer)
1781                    (mm-enable-multibyte)))
1782          (goto-char (point-min))
1783          (setq case-fold-search t)
1784          (while (re-search-forward
1785                  "&#\\(?:x\\([89][0-9a-f]\\)\\|\\(1[2-5][0-9]\\)\\);" nil t)
1786            (when (setq char
1787                        (cdr (assq (if (match-beginning 1)
1788                                       (string-to-number (match-string 1) 16)
1789                                     (string-to-number (match-string 2)))
1790                                   mm-extra-numeric-entities)))
1791              (replace-match (char-to-string char))))
1792          ;; Remove "soft hyphens".
1793          (goto-char (point-min))
1794          (while (search-forward "" nil t)
1795            (replace-match "" t t))
1796          (libxml-parse-html-region (point-min) (point-max))))
1797       (unless (bobp)
1798         (insert "\n"))
1799       (mm-handle-set-undisplayer
1800        handle
1801        `(lambda ()
1802           (let ((inhibit-read-only t))
1803             (delete-region ,(point-min-marker)
1804                            ,(point-max-marker))))))))
1805
1806 (defun mm-handle-filename (handle)
1807   "Return filename of HANDLE if any."
1808   (or (mail-content-type-get (mm-handle-type handle)
1809                              'name)
1810       (mail-content-type-get (mm-handle-disposition handle)
1811                              'filename)))
1812
1813 (provide 'mm-decode)
1814
1815 ;; Local Variables:
1816 ;; coding: iso-8859-1
1817 ;; End:
1818
1819 ;;; mm-decode.el ends here