lisp/gnus/mm-decode.el

   1 ;;; mm-decode.el --- Functions for decoding MIME things
   2
   3 ;; Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   4 ;;   2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
   5
   6 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   7 ;;      MORIOKA Tomohiko <morioka@jaist.ac.jp>
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software: you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation, either version 3 of the License, or
  13 ;; (at your option) any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;;; Code:
  26
  27 ;; For Emacs < 22.2.
  28 (eval-and-compile
  29   (unless (fboundp 'declare-function) (defmacro declare-function (&rest r))))
  30
  31 (require 'mail-parse)
  32 (require 'mailcap)
  33 (require 'mm-bodies)
  34 (require 'gnus-util)
  35 (eval-when-compile (require 'cl)
  36                    (require 'term))
  37
  38 (autoload 'mm-inline-partial "mm-partial")
  39 (autoload 'mm-inline-external-body "mm-extern")
  40 (autoload 'mm-extern-cache-contents "mm-extern")
  41 (autoload 'mm-insert-inline "mm-view")
  42
  43 (defvar gnus-current-window-configuration)
  44
  45 (add-hook 'gnus-exit-gnus-hook 'mm-destroy-postponed-undisplay-list)
  46
  47 (defgroup mime-display ()
  48   "Display of MIME in mail and news articles."
  49   :link '(custom-manual "(emacs-mime)Display Customization")
  50   :version "21.1"
  51   :group 'mail
  52   :group 'news
  53   :group 'multimedia)
  54
  55 (defgroup mime-security ()
  56   "MIME security in mail and news articles."
  57   :link '(custom-manual "(emacs-mime)Display Customization")
  58   :group 'mail
  59   :group 'news
  60   :group 'multimedia)
  61
  62 ;;; Convenience macros.
  63
  64 (defmacro mm-handle-buffer (handle)
  65   `(nth 0 ,handle))
  66 (defmacro mm-handle-type (handle)
  67   `(nth 1 ,handle))
  68 (defsubst mm-handle-media-type (handle)
  69   (if (stringp (car handle))
  70       (car handle)
  71     (car (mm-handle-type handle))))
  72 (defsubst mm-handle-media-supertype (handle)
  73   (car (split-string (mm-handle-media-type handle) "/")))
  74 (defsubst mm-handle-media-subtype (handle)
  75   (cadr (split-string (mm-handle-media-type handle) "/")))
  76 (defmacro mm-handle-encoding (handle)
  77   `(nth 2 ,handle))
  78 (defmacro mm-handle-undisplayer (handle)
  79   `(nth 3 ,handle))
  80 (defmacro mm-handle-set-undisplayer (handle function)
  81   `(setcar (nthcdr 3 ,handle) ,function))
  82 (defmacro mm-handle-disposition (handle)
  83   `(nth 4 ,handle))
  84 (defmacro mm-handle-description (handle)
  85   `(nth 5 ,handle))
  86 (defmacro mm-handle-cache (handle)
  87   `(nth 6 ,handle))
  88 (defmacro mm-handle-set-cache (handle contents)
  89   `(setcar (nthcdr 6 ,handle) ,contents))
  90 (defmacro mm-handle-id (handle)
  91   `(nth 7 ,handle))
  92 (defmacro mm-handle-multipart-original-buffer (handle)
  93   `(get-text-property 0 'buffer (car ,handle)))
  94 (defmacro mm-handle-multipart-from (handle)
  95   `(get-text-property 0 'from (car ,handle)))
  96 (defmacro mm-handle-multipart-ctl-parameter (handle parameter)
  97   `(get-text-property 0 ,parameter (car ,handle)))
  98
  99 (defmacro mm-make-handle (&optional buffer type encoding undisplayer
 100                                     disposition description cache
 101                                     id)
 102   `(list ,buffer ,type ,encoding ,undisplayer
 103          ,disposition ,description ,cache ,id))
 104
 105 (defcustom mm-text-html-renderer
 106   (cond ((executable-find "w3m")
 107          (if (locate-library "w3m")
 108              'w3m
 109            'w3m-standalone))
 110         ((executable-find "links") 'links)
 111         ((executable-find "lynx") 'lynx)
 112         ((locate-library "w3") 'w3)
 113         ((locate-library "html2text") 'html2text)
 114         (t nil))
 115   "Render of HTML contents.
 116 It is one of defined renderer types, or a rendering function.
 117 The defined renderer types are:
 118 `w3m'  : use emacs-w3m;
 119 `w3m-standalone': use w3m;
 120 `links': use links;
 121 `lynx' : use lynx;
 122 `w3'   : use Emacs/W3;
 123 `html2text' : use html2text;
 124 nil    : use external viewer (default web browser)."
 125   :version "23.0" ;; No Gnus
 126   :type '(choice (const w3)
 127                  (const w3m :tag "emacs-w3m")
 128                  (const w3m-standalone :tag "standalone w3m" )
 129                  (const links)
 130                  (const lynx)
 131                  (const html2text)
 132                  (const nil :tag "External viewer")
 133                  (function))
 134   :group 'mime-display)
 135
 136 (defvar mm-inline-text-html-renderer nil
 137   "Function used for rendering inline HTML contents.
 138 It is suggested to customize `mm-text-html-renderer' instead.")
 139
 140 (defcustom mm-inline-text-html-with-images nil
 141   "If non-nil, Gnus will allow retrieving images in HTML contents with
 142 the <img> tags.  It has no effect on Emacs/w3.  See also the
 143 documentation for the `mm-w3m-safe-url-regexp' variable."
 144   :version "22.1"
 145   :type 'boolean
 146   :group 'mime-display)
 147
 148 (defcustom mm-w3m-safe-url-regexp "\\`cid:"
 149   "Regexp matching URLs which are considered to be safe.
 150 Some HTML mails might contain a nasty trick used by spammers, using
 151 the <img> tag which is far more evil than the [Click Here!] button.
 152 It is most likely intended to check whether the ominous spam mail has
 153 reached your eyes or not, in which case the spammer knows for sure
 154 that your email address is valid.  It is done by embedding an
 155 identifier string into a URL that you might automatically retrieve
 156 when displaying the image.  The default value is \"\\\\`cid:\" which only
 157 matches parts embedded to the Multipart/Related type MIME contents and
 158 Gnus will never connect to the spammer's site arbitrarily.  You may
 159 set this variable to nil if you consider all urls to be safe."
 160   :version "22.1"
 161   :type '(choice (regexp :tag "Regexp")
 162                  (const :tag "All URLs are safe" nil))
 163   :group 'mime-display)
 164
 165 (defcustom mm-inline-text-html-with-w3m-keymap t
 166   "If non-nil, use emacs-w3m command keys in the article buffer."
 167   :version "22.1"
 168   :type 'boolean
 169   :group 'mime-display)
 170
 171 (defcustom mm-enable-external t
 172   "Indicate whether external MIME handlers should be used.
 173
 174 If t, all defined external MIME handlers are used.  If nil, files are saved by
 175 `mailcap-save-binary-file'.  If it is the symbol `ask', you are prompted
 176 before the external MIME handler is invoked."
 177   :version "22.1"
 178   :type '(choice (const :tag "Always" t)
 179                  (const :tag "Never" nil)
 180                  (const :tag "Ask" ask))
 181   :group 'mime-display)
 182
 183 (defcustom mm-inline-media-tests
 184   '(("image/p?jpeg"
 185      mm-inline-image
 186      (lambda (handle)
 187        (mm-valid-and-fit-image-p 'jpeg handle)))
 188     ("image/png"
 189      mm-inline-image
 190      (lambda (handle)
 191        (mm-valid-and-fit-image-p 'png handle)))
 192     ("image/gif"
 193      mm-inline-image
 194      (lambda (handle)
 195        (mm-valid-and-fit-image-p 'gif handle)))
 196     ("image/tiff"
 197      mm-inline-image
 198      (lambda (handle)
 199        (mm-valid-and-fit-image-p 'tiff handle)) )
 200     ("image/xbm"
 201      mm-inline-image
 202      (lambda (handle)
 203        (mm-valid-and-fit-image-p 'xbm handle)))
 204     ("image/x-xbitmap"
 205      mm-inline-image
 206      (lambda (handle)
 207        (mm-valid-and-fit-image-p 'xbm handle)))
 208     ("image/xpm"
 209      mm-inline-image
 210      (lambda (handle)
 211        (mm-valid-and-fit-image-p 'xpm handle)))
 212     ("image/x-xpixmap"
 213      mm-inline-image
 214      (lambda (handle)
 215        (mm-valid-and-fit-image-p 'xpm handle)))
 216     ("image/bmp"
 217      mm-inline-image
 218      (lambda (handle)
 219        (mm-valid-and-fit-image-p 'bmp handle)))
 220     ("image/x-portable-bitmap"
 221      mm-inline-image
 222      (lambda (handle)
 223        (mm-valid-and-fit-image-p 'pbm handle)))
 224     ("text/plain" mm-inline-text identity)
 225     ("text/enriched" mm-inline-text identity)
 226     ("text/richtext" mm-inline-text identity)
 227     ("text/x-patch" mm-display-patch-inline
 228      (lambda (handle)
 229        ;; If the diff-mode.el package is installed, the function is
 230        ;; autoloaded.  Checking (locate-library "diff-mode") would be trying
 231        ;; to cater to broken installations.  OTOH checking the function
 232        ;; makes it possible to install another package which provides an
 233        ;; alternative implementation of diff-mode.  --Stef
 234        (fboundp 'diff-mode)))
 235     ;; In case mime.types uses x-diff (as does Debian's mime-support-3.40).
 236     ("text/x-diff" mm-display-patch-inline
 237      (lambda (handle) (fboundp 'diff-mode)))
 238     ("application/emacs-lisp" mm-display-elisp-inline identity)
 239     ("application/x-emacs-lisp" mm-display-elisp-inline identity)
 240     ("text/dns" mm-display-dns-inline identity)
 241     ("text/html"
 242      mm-inline-text-html
 243      (lambda (handle)
 244        (or mm-inline-text-html-renderer
 245            mm-text-html-renderer)))
 246     ("text/x-vcard"
 247      mm-inline-text-vcard
 248      (lambda (handle)
 249        (or (featurep 'vcard)
 250            (locate-library "vcard"))))
 251     ("message/delivery-status" mm-inline-text identity)
 252     ("message/rfc822" mm-inline-message identity)
 253     ("message/partial" mm-inline-partial identity)
 254     ("message/external-body" mm-inline-external-body identity)
 255     ("text/.*" mm-inline-text identity)
 256     ("audio/wav" mm-inline-audio
 257      (lambda (handle)
 258        (and (or (featurep 'nas-sound) (featurep 'native-sound))
 259             (device-sound-enabled-p))))
 260     ("audio/au"
 261      mm-inline-audio
 262      (lambda (handle)
 263        (and (or (featurep 'nas-sound) (featurep 'native-sound))
 264             (device-sound-enabled-p))))
 265     ("application/pgp-signature" ignore identity)
 266     ("application/x-pkcs7-signature" ignore identity)
 267     ("application/pkcs7-signature" ignore identity)
 268     ("application/x-pkcs7-mime" ignore identity)
 269     ("application/pkcs7-mime" ignore identity)
 270     ("multipart/alternative" ignore identity)
 271     ("multipart/mixed" ignore identity)
 272     ("multipart/related" ignore identity)
 273     ;; Disable audio and image
 274     ("audio/.*" ignore ignore)
 275     ("image/.*" ignore ignore)
 276     ;; Default to displaying as text
 277     (".*" mm-inline-text mm-readable-p))
 278   "Alist of media types/tests saying whether types can be displayed inline."
 279   :type '(repeat (list (regexp :tag "MIME type")
 280                        (function :tag "Display function")
 281                        (function :tag "Display test")))
 282   :group 'mime-display)
 283
 284 (defcustom mm-inlined-types
 285   '("image/.*" "text/.*" "message/delivery-status" "message/rfc822"
 286     "message/partial" "message/external-body" "application/emacs-lisp"
 287     "application/x-emacs-lisp"
 288     "application/pgp-signature" "application/x-pkcs7-signature"
 289     "application/pkcs7-signature" "application/x-pkcs7-mime"
 290     "application/pkcs7-mime"
 291     ;; Mutt still uses this even though it has already been withdrawn.
 292     "application/pgp")
 293   "List of media types that are to be displayed inline.
 294 See also `mm-inline-media-tests', which says how to display a media
 295 type inline."
 296   :type '(repeat regexp)
 297   :group 'mime-display)
 298
 299 (defcustom mm-keep-viewer-alive-types
 300   '("application/postscript" "application/msword" "application/vnd.ms-excel"
 301     "application/pdf" "application/x-dvi")
 302   "List of media types for which the external viewer will not be killed
 303 when selecting a different article."
 304   :version "22.1"
 305   :type '(repeat regexp)
 306   :group 'mime-display)
 307
 308 (defcustom mm-automatic-display
 309   '("text/plain" "text/enriched" "text/richtext" "text/html" "text/x-verbatim"
 310     "text/x-vcard" "image/.*" "message/delivery-status" "multipart/.*"
 311     "message/rfc822" "text/x-patch" "text/dns" "application/pgp-signature"
 312     "application/emacs-lisp" "application/x-emacs-lisp"
 313     "application/x-pkcs7-signature"
 314     "application/pkcs7-signature" "application/x-pkcs7-mime"
 315     "application/pkcs7-mime"
 316     ;; Mutt still uses this even though it has already been withdrawn.
 317     "application/pgp\\'")
 318   "A list of MIME types to be displayed automatically."
 319   :type '(repeat regexp)
 320   :group 'mime-display)
 321
 322 (defcustom mm-attachment-override-types '("text/x-vcard"
 323                                           "application/pkcs7-mime"
 324                                           "application/x-pkcs7-mime"
 325                                           "application/pkcs7-signature"
 326                                           "application/x-pkcs7-signature")
 327   "Types to have \"attachment\" ignored if they can be displayed inline."
 328   :type '(repeat regexp)
 329   :group 'mime-display)
 330
 331 (defcustom mm-inline-override-types nil
 332   "Types to be treated as attachments even if they can be displayed inline."
 333   :type '(repeat regexp)
 334   :group 'mime-display)
 335
 336 (defcustom mm-automatic-external-display nil
 337   "List of MIME type regexps that will be displayed externally automatically."
 338   :type '(repeat regexp)
 339   :group 'mime-display)
 340
 341 (defcustom mm-discouraged-alternatives nil
 342   "List of MIME types that are discouraged when viewing multipart/alternative.
 343 Viewing agents are supposed to view the last possible part of a message,
 344 as that is supposed to be the richest.  However, users may prefer other
 345 types instead, and this list says what types are most unwanted.  If,
 346 for instance, text/html parts are very unwanted, and text/richtext are
 347 somewhat unwanted, then the value of this variable should be set
 348 to:
 349
 350  (\"text/html\" \"text/richtext\")
 351
 352 Adding \"image/.*\" might also be useful.  Spammers use it as the
 353 prefered part of multipart/alternative messages.  See also
 354 `gnus-buttonized-mime-types', to which adding \"multipart/alternative\"
 355 enables you to choose manually one of two types those mails include."
 356   :type '(repeat regexp) ;; See `mm-preferred-alternative-precedence'.
 357   :group 'mime-display)
 358
 359 (defcustom mm-tmp-directory
 360   (if (fboundp 'temp-directory)
 361       (temp-directory)
 362     (if (boundp 'temporary-file-directory)
 363         temporary-file-directory
 364       "/tmp/"))
 365   "Where mm will store its temporary files."
 366   :type 'directory
 367   :group 'mime-display)
 368
 369 (defcustom mm-inline-large-images nil
 370   "If non-nil, then all images fit in the buffer."
 371   :type 'boolean
 372   :group 'mime-display)
 373
 374 (defcustom mm-file-name-rewrite-functions
 375   '(mm-file-name-delete-control mm-file-name-delete-gotchas)
 376   "List of functions used for rewriting file names of MIME parts.
 377 Each function takes a file name as input and returns a file name.
 378
 379 Ready-made functions include `mm-file-name-delete-control',
 380 `mm-file-name-delete-gotchas' (you should not remove these two
 381 functions), `mm-file-name-delete-whitespace',
 382 `mm-file-name-trim-whitespace', `mm-file-name-collapse-whitespace',
 383 `mm-file-name-replace-whitespace', `capitalize', `downcase',
 384 `upcase', and `upcase-initials'."
 385   :type '(list (set :inline t
 386                     (const mm-file-name-delete-control)
 387                     (const mm-file-name-delete-gotchas)
 388                     (const mm-file-name-delete-whitespace)
 389                     (const mm-file-name-trim-whitespace)
 390                     (const mm-file-name-collapse-whitespace)
 391                     (const mm-file-name-replace-whitespace)
 392                     (const capitalize)
 393                     (const downcase)
 394                     (const upcase)
 395                     (const upcase-initials)
 396                (repeat :inline t
 397                        :tag "Function"
 398                        function)))
 399   :version "23.1" ;; No Gnus
 400   :group 'mime-display)
 401
 402
 403 (defvar mm-path-name-rewrite-functions nil
 404   "*List of functions for rewriting the full file names of MIME parts.
 405 This is used when viewing parts externally, and is meant for
 406 transforming the absolute name so that non-compliant programs can find
 407 the file where it's saved.
 408
 409 Each function takes a file name as input and returns a file name.")
 410
 411 (defvar mm-file-name-replace-whitespace nil
 412   "String used for replacing whitespace characters; default is `\"_\"'.")
 413
 414 (defcustom mm-default-directory nil
 415   "The default directory where mm will save files.
 416 If not set, `default-directory' will be used."
 417   :type '(choice directory (const :tag "Default" nil))
 418   :group 'mime-display)
 419
 420 (defcustom mm-attachment-file-modes 384
 421   "Set the mode bits of saved attachments to this integer."
 422   :version "22.1"
 423   :type 'integer
 424   :group 'mime-display)
 425
 426 (defcustom mm-external-terminal-program "xterm"
 427   "The program to start an external terminal."
 428   :version "22.1"
 429   :type 'string
 430   :group 'mime-display)
 431
 432 ;;; Internal variables.
 433
 434 (defvar mm-last-shell-command "")
 435 (defvar mm-content-id-alist nil)
 436 (defvar mm-postponed-undisplay-list nil)
 437
 438 ;; According to RFC2046, in particular, in a digest, the default
 439 ;; Content-Type value for a body part is changed from "text/plain" to
 440 ;; "message/rfc822".
 441 (defvar mm-dissect-default-type "text/plain")
 442
 443 (autoload 'mml2015-verify "mml2015")
 444 (autoload 'mml2015-verify-test "mml2015")
 445 (autoload 'mml-smime-verify "mml-smime")
 446 (autoload 'mml-smime-verify-test "mml-smime")
 447
 448 (defvar mm-verify-function-alist
 449   '(("application/pgp-signature" mml2015-verify "PGP" mml2015-verify-test)
 450     ("application/x-gnus-pgp-signature" mm-uu-pgp-signed-extract-1 "PGP"
 451      mm-uu-pgp-signed-test)
 452     ("application/pkcs7-signature" mml-smime-verify "S/MIME"
 453      mml-smime-verify-test)
 454     ("application/x-pkcs7-signature" mml-smime-verify "S/MIME"
 455      mml-smime-verify-test)))
 456
 457 (defcustom mm-verify-option 'never
 458   "Option of verifying signed parts.
 459 `never', not verify; `always', always verify;
 460 `known', only verify known protocols.  Otherwise, ask user.
 461
 462 When set to `always' or `known', you should add
 463 \"multipart/signed\" to `gnus-buttonized-mime-types' to see
 464 result of the verification."
 465   :version "22.1"
 466   :type '(choice (item always)
 467                  (item never)
 468                  (item :tag "only known protocols" known)
 469                  (item :tag "ask" nil))
 470   :group 'mime-security)
 471
 472 (autoload 'mml2015-decrypt "mml2015")
 473 (autoload 'mml2015-decrypt-test "mml2015")
 474
 475 (defvar mm-decrypt-function-alist
 476   '(("application/pgp-encrypted" mml2015-decrypt "PGP" mml2015-decrypt-test)
 477     ("application/x-gnus-pgp-encrypted" mm-uu-pgp-encrypted-extract-1 "PGP"
 478      mm-uu-pgp-encrypted-test)))
 479
 480 (defcustom mm-decrypt-option nil
 481   "Option of decrypting encrypted parts.
 482 `never', not decrypt; `always', always decrypt;
 483 `known', only decrypt known protocols.  Otherwise, ask user."
 484   :version "22.1"
 485   :type '(choice (item always)
 486                  (item never)
 487                  (item :tag "only known protocols" known)
 488                  (item :tag "ask" nil))
 489   :group 'mime-security)
 490
 491 (defvar mm-viewer-completion-map
 492   (let ((map (make-sparse-keymap 'mm-viewer-completion-map)))
 493     (set-keymap-parent map minibuffer-local-completion-map)
 494     ;; Should we bind other key to minibuffer-complete-word?
 495     (define-key map " " 'self-insert-command)
 496     map)
 497   "Keymap for input viewer with completion.")
 498
 499 (defvar mm-viewer-completion-map
 500   (let ((map (make-sparse-keymap 'mm-viewer-completion-map)))
 501     (set-keymap-parent map minibuffer-local-completion-map)
 502     ;; Should we bind other key to minibuffer-complete-word?
 503     (define-key map " " 'self-insert-command)
 504     map)
 505   "Keymap for input viewer with completion.")
 506
 507 ;;; The functions.
 508
 509 (defun mm-alist-to-plist (alist)
 510   "Convert association list ALIST into the equivalent property-list form.
 511 The plist is returned.  This converts from
 512
 513 \((a . 1) (b . 2) (c . 3))
 514
 515 into
 516
 517 \(a 1 b 2 c 3)
 518
 519 The original alist is not modified.  See also `destructive-alist-to-plist'."
 520   (let (plist)
 521     (while alist
 522       (let ((el (car alist)))
 523         (setq plist (cons (cdr el) (cons (car el) plist))))
 524       (setq alist (cdr alist)))
 525     (nreverse plist)))
 526
 527 (defun mm-keep-viewer-alive-p (handle)
 528   "Say whether external viewer for HANDLE should stay alive."
 529   (let ((types mm-keep-viewer-alive-types)
 530         (type (mm-handle-media-type handle))
 531         ty)
 532     (catch 'found
 533       (while (setq ty (pop types))
 534         (when (string-match ty type)
 535           (throw 'found t))))))
 536
 537 (defun mm-handle-set-external-undisplayer (handle function)
 538   "Set the undisplayer for HANDLE to FUNCTION.
 539 Postpone undisplaying of viewers for types in
 540 `mm-keep-viewer-alive-types'."
 541   (if (mm-keep-viewer-alive-p handle)
 542       (let ((new-handle (copy-sequence handle)))
 543         (mm-handle-set-undisplayer new-handle function)
 544         (mm-handle-set-undisplayer handle nil)
 545         (push new-handle mm-postponed-undisplay-list))
 546     (mm-handle-set-undisplayer handle function)))
 547
 548 (defun mm-destroy-postponed-undisplay-list ()
 549   (when mm-postponed-undisplay-list
 550     (message "Destroying external MIME viewers")
 551     (mm-destroy-parts mm-postponed-undisplay-list)))
 552
 553 (defun mm-dissect-buffer (&optional no-strict-mime loose-mime from)
 554   "Dissect the current buffer and return a list of MIME handles."
 555   (save-excursion
 556     (let (ct ctl type subtype cte cd description id result)
 557       (save-restriction
 558         (mail-narrow-to-head)
 559         (when (or no-strict-mime
 560                   loose-mime
 561                   (mail-fetch-field "mime-version"))
 562           (setq ct (mail-fetch-field "content-type")
 563                 ctl (and ct (mail-header-parse-content-type ct))
 564                 cte (mail-fetch-field "content-transfer-encoding")
 565                 cd (mail-fetch-field "content-disposition")
 566                 ;; Newlines in description should be stripped so as
 567                 ;; not to break the MIME tag into two or more lines.
 568                 description (message-fetch-field "content-description")
 569                 id (mail-fetch-field "content-id"))
 570           (unless from
 571             (setq from (mail-fetch-field "from")))
 572           ;; FIXME: In some circumstances, this code is running within
 573           ;; an unibyte macro.  mail-extract-address-components
 574           ;; creates unibyte buffers. This `if', though not a perfect
 575           ;; solution, avoids most of them.
 576           (if from
 577               (setq from (cadr (mail-extract-address-components from))))
 578           (if description
 579               (setq description (mail-decode-encoded-word-string
 580                                  description)))))
 581       (if (or (not ctl)
 582               (not (string-match "/" (car ctl))))
 583           (mm-dissect-singlepart
 584            (list mm-dissect-default-type)
 585            (and cte (intern (downcase (mail-header-strip cte))))
 586            no-strict-mime
 587            (and cd (mail-header-parse-content-disposition cd))
 588            description)
 589         (setq type (split-string (car ctl) "/"))
 590         (setq subtype (cadr type)
 591               type (car type))
 592         (setq
 593          result
 594          (cond
 595           ((equal type "multipart")
 596            (let ((mm-dissect-default-type (if (equal subtype "digest")
 597                                               "message/rfc822"
 598                                             "text/plain"))
 599                  (start (cdr (assq 'start (cdr ctl)))))
 600              (add-text-properties 0 (length (car ctl))
 601                                   (mm-alist-to-plist (cdr ctl)) (car ctl))
 602
 603              ;; what really needs to be done here is a way to link a
 604              ;; MIME handle back to it's parent MIME handle (in a multilevel
 605              ;; MIME article).  That would probably require changing
 606              ;; the mm-handle API so we simply store the multipart buffer
 607              ;; name as a text property of the "multipart/whatever" string.
 608              (add-text-properties 0 (length (car ctl))
 609                                   (list 'buffer (mm-copy-to-buffer)
 610                                         'from from
 611                                         'start start)
 612                                   (car ctl))
 613              (cons (car ctl) (mm-dissect-multipart ctl from))))
 614           (t
 615            (mm-possibly-verify-or-decrypt
 616             (mm-dissect-singlepart
 617              ctl
 618              (and cte (intern (downcase (mail-header-strip cte))))
 619              no-strict-mime
 620              (and cd (mail-header-parse-content-disposition cd))
 621              description id)
 622             ctl))))
 623         (when id
 624           (when (string-match " *<\\(.*\\)> *" id)
 625             (setq id (match-string 1 id)))
 626           (push (cons id result) mm-content-id-alist))
 627         result))))
 628
 629 (defun mm-dissect-singlepart (ctl cte &optional force cdl description id)
 630   (when (or force
 631             (if (equal "text/plain" (car ctl))
 632                 (assoc 'format ctl)
 633               t))
 634     (mm-make-handle
 635      (mm-copy-to-buffer) ctl cte nil cdl description nil id)))
 636
 637 (defun mm-dissect-multipart (ctl from)
 638   (goto-char (point-min))
 639   (let* ((boundary (concat "\n--" (mail-content-type-get ctl 'boundary)))
 640          (close-delimiter (concat (regexp-quote boundary) "--[ \t]*$"))
 641          start parts
 642          (end (save-excursion
 643                 (goto-char (point-max))
 644                 (if (re-search-backward close-delimiter nil t)
 645                     (match-beginning 0)
 646                   (point-max)))))
 647     (setq boundary (concat (regexp-quote boundary) "[ \t]*$"))
 648     (while (and (< (point) end) (re-search-forward boundary end t))
 649       (goto-char (match-beginning 0))
 650       (when start
 651         (save-excursion
 652           (save-restriction
 653             (narrow-to-region start (point))
 654             (setq parts (nconc (list (mm-dissect-buffer t nil from)) parts)))))
 655       (end-of-line 2)
 656       (or (looking-at boundary)
 657           (forward-line 1))
 658       (setq start (point)))
 659     (when (and start (< start end))
 660       (save-excursion
 661         (save-restriction
 662           (narrow-to-region start end)
 663           (setq parts (nconc (list (mm-dissect-buffer t nil from)) parts)))))
 664     (mm-possibly-verify-or-decrypt (nreverse parts) ctl)))
 665
 666 (defun mm-copy-to-buffer ()
 667   "Copy the contents of the current buffer to a fresh buffer."
 668   (let ((obuf (current-buffer))
 669         (mb (mm-multibyte-p))
 670         beg)
 671     (goto-char (point-min))
 672     (search-forward-regexp "^\n" nil t)
 673     (setq beg (point))
 674     (with-current-buffer
 675           (generate-new-buffer " *mm*")
 676       ;; Preserve the data's unibyteness (for url-insert-file-contents).
 677       (mm-set-buffer-multibyte mb)
 678       (insert-buffer-substring obuf beg)
 679       (current-buffer))))
 680
 681 (defun mm-display-parts (handle &optional no-default)
 682   (if (stringp (car handle))
 683       (mapcar 'mm-display-parts (cdr handle))
 684     (if (bufferp (car handle))
 685         (save-restriction
 686           (narrow-to-region (point) (point))
 687           (mm-display-part handle)
 688           (goto-char (point-max)))
 689       (mapcar 'mm-display-parts handle))))
 690
 691 (defun mm-display-part (handle &optional no-default)
 692   "Display the MIME part represented by HANDLE.
 693 Returns nil if the part is removed; inline if displayed inline;
 694 external if displayed external."
 695   (save-excursion
 696     (mailcap-parse-mailcaps)
 697     (if (mm-handle-displayed-p handle)
 698         (mm-remove-part handle)
 699       (let* ((ehandle (if (equal (mm-handle-media-type handle)
 700                                  "message/external-body")
 701                           (progn
 702                             (unless (mm-handle-cache handle)
 703                               (mm-extern-cache-contents handle))
 704                             (mm-handle-cache handle))
 705                         handle))
 706              (type (mm-handle-media-type ehandle))
 707              (method (mailcap-mime-info type))
 708              (filename (or (mail-content-type-get
 709                             (mm-handle-disposition handle) 'filename)
 710                            (mail-content-type-get
 711                             (mm-handle-type handle) 'name)
 712                            "<file>"))
 713              (external mm-enable-external))
 714         (if (and (mm-inlinable-p ehandle)
 715                  (mm-inlined-p ehandle))
 716             (progn
 717               (forward-line 1)
 718               (mm-display-inline handle)
 719               'inline)
 720           (when (or method
 721                     (not no-default))
 722             (if (and (not method)
 723                      (equal "text" (car (split-string type "/"))))
 724                 (progn
 725                   (forward-line 1)
 726                   (mm-insert-inline handle (mm-get-part handle))
 727                   'inline)
 728               (setq external
 729                     (and method ;; If nil, we always use "save".
 730                        (stringp method) ;; 'mailcap-save-binary-file
 731                        (or (eq mm-enable-external t)
 732                            (and (eq mm-enable-external 'ask)
 733                                 (y-or-n-p
 734                                  (concat
 735                                   "Display part (" type
 736                                   ") using external program"
 737                                   ;; Can non-string method ever happen?
 738                                   (if (stringp method)
 739                                       (concat
 740                                        " \"" (format method filename) "\"")
 741                                     "")
 742                                     "? "))))))
 743               (if external
 744                   (mm-display-external
 745                    handle (or method 'mailcap-save-binary-file))
 746                 (mm-display-external
 747                  handle 'mailcap-save-binary-file)))))))))
 748
 749 (declare-function gnus-configure-windows "gnus-win" (setting &optional force))
 750
 751 (defun mm-display-external (handle method)
 752   "Display HANDLE using METHOD."
 753   (let ((outbuf (current-buffer)))
 754     (mm-with-unibyte-buffer
 755       (if (functionp method)
 756           (let ((cur (current-buffer)))
 757             (if (eq method 'mailcap-save-binary-file)
 758                 (progn
 759                   (set-buffer (generate-new-buffer " *mm*"))
 760                   (setq method nil))
 761               (mm-insert-part handle)
 762               (mm-add-meta-html-tag handle)
 763               (let ((win (get-buffer-window cur t)))
 764                 (when win
 765                   (select-window win)))
 766               (switch-to-buffer (generate-new-buffer " *mm*")))
 767             (buffer-disable-undo)
 768             (mm-set-buffer-file-coding-system mm-binary-coding-system)
 769             (insert-buffer-substring cur)
 770             (goto-char (point-min))
 771             (when method
 772               (message "Viewing with %s" method))
 773             (let ((mm (current-buffer))
 774                   (non-viewer (assq 'non-viewer
 775                                     (mailcap-mime-info
 776                                      (mm-handle-media-type handle) t))))
 777               (unwind-protect
 778                   (if method
 779                       (funcall method)
 780                     (mm-save-part handle))
 781                 (when (and (not non-viewer)
 782                            method)
 783                   (mm-handle-set-undisplayer handle mm)))))
 784         ;; The function is a string to be executed.
 785         (mm-insert-part handle)
 786         (mm-add-meta-html-tag handle)
 787         (let* ((dir (mm-make-temp-file
 788                      (expand-file-name "emm." mm-tmp-directory) 'dir))
 789                (filename (or
 790                           (mail-content-type-get
 791                            (mm-handle-disposition handle) 'filename)
 792                           (mail-content-type-get
 793                            (mm-handle-type handle) 'name)))
 794                (mime-info (mailcap-mime-info
 795                            (mm-handle-media-type handle) t))
 796                (needsterm (or (assoc "needsterm" mime-info)
 797                               (assoc "needsterminal" mime-info)))
 798                (copiousoutput (assoc "copiousoutput" mime-info))
 799                file buffer)
 800           ;; We create a private sub-directory where we store our files.
 801           (set-file-modes dir #o700)
 802           (if filename
 803               (setq file (expand-file-name
 804                           (gnus-map-function mm-file-name-rewrite-functions
 805                                              (file-name-nondirectory filename))
 806                           dir))
 807             ;; Use nametemplate (defined in RFC1524) if it is specified
 808             ;; in mailcap.
 809             (let ((suffix (cdr (assoc "nametemplate" mime-info))))
 810               (if (and suffix
 811                        (string-match "\\`%s\\(\\..+\\)\\'" suffix))
 812                   (setq suffix (match-string 1 suffix))
 813                 ;; Otherwise, use a suffix according to
 814                 ;; `mailcap-mime-extensions'.
 815                 (setq suffix (car (rassoc (mm-handle-media-type handle)
 816                                           mailcap-mime-extensions))))
 817               (setq file (mm-make-temp-file (expand-file-name "mm." dir)
 818                                             nil suffix))))
 819           (let ((coding-system-for-write mm-binary-coding-system))
 820             (write-region (point-min) (point-max) file nil 'nomesg))
 821           ;; The file is deleted after the viewer exists.  If the users edits
 822           ;; the file, changes will be lost.  Set file to read-only to make it
 823           ;; clear.
 824           (set-file-modes file #o400)
 825           (message "Viewing with %s" method)
 826           (cond
 827            (needsterm
 828             (let ((command (mm-mailcap-command
 829                             method file (mm-handle-type handle))))
 830               (unwind-protect
 831                   (if window-system
 832                       (start-process "*display*" nil
 833                                      mm-external-terminal-program
 834                                      "-e" shell-file-name
 835                                      shell-command-switch command)
 836                     (require 'term)
 837                     (require 'gnus-win)
 838                     (set-buffer
 839                      (setq buffer
 840                            (make-term "display"
 841                                       shell-file-name
 842                                       nil
 843                                       shell-command-switch command)))
 844                     (term-mode)
 845                     (term-char-mode)
 846                     (set-process-sentinel
 847                      (get-buffer-process buffer)
 848                      `(lambda (process state)
 849                         (if (eq 'exit (process-status process))
 850                             (gnus-configure-windows
 851                              ',gnus-current-window-configuration))))
 852                     (gnus-configure-windows 'display-term))
 853                 (mm-handle-set-external-undisplayer handle (cons file buffer)))
 854               (message "Displaying %s..." command))
 855             'external)
 856            (copiousoutput
 857             (with-current-buffer outbuf
 858               (forward-line 1)
 859               (mm-insert-inline
 860                handle
 861                (unwind-protect
 862                    (progn
 863                      (call-process shell-file-name nil
 864                                    (setq buffer
 865                                          (generate-new-buffer " *mm*"))
 866                                    nil
 867                                    shell-command-switch
 868                                    (mm-mailcap-command
 869                                     method file (mm-handle-type handle)))
 870                      (if (buffer-live-p buffer)
 871                          (with-current-buffer buffer
 872                            (buffer-string))))
 873                  (progn
 874                    (ignore-errors (delete-file file))
 875                    (ignore-errors (delete-directory
 876                                    (file-name-directory file)))
 877                    (ignore-errors (kill-buffer buffer))))))
 878             'inline)
 879            (t
 880             ;; Deleting the temp file should be postponed for some wrappers,
 881             ;; shell scripts, and so on, which might exit right after having
 882             ;; started a viewer command as a background job.
 883             (let ((command (mm-mailcap-command
 884                             method file (mm-handle-type handle))))
 885               (unwind-protect
 886                   (progn
 887                     (start-process "*display*"
 888                                    (setq buffer
 889                                          (generate-new-buffer " *mm*"))
 890                                    shell-file-name
 891                                    shell-command-switch command)
 892                     (set-process-sentinel
 893                      (get-buffer-process buffer)
 894                      (lexical-let ;; Don't use `let'.
 895                          ;; Function used to remove temp file and directory.
 896                          ((fn `(lambda nil
 897                                  ;; Don't use `ignore-errors'.
 898                                  (condition-case nil
 899                                      (delete-file ,file)
 900                                    (error))
 901                                  (condition-case nil
 902                                      (delete-directory
 903                                       ,(file-name-directory file))
 904                                    (error))))
 905                           ;; Form uses to kill the process buffer and
 906                           ;; remove the undisplayer.
 907                           (fm `(progn
 908                                  (kill-buffer ,buffer)
 909                                  ,(macroexpand
 910                                    (list 'mm-handle-set-undisplayer
 911                                          (list 'quote handle)
 912                                          nil))))
 913                           ;; Message to be issued when the process exits.
 914                           (done (format "Displaying %s...done" command))
 915                           ;; In particular, the timer object (which is
 916                           ;; a vector in Emacs but is a list in XEmacs)
 917                           ;; requires that it is lexically scoped.
 918                           (timer (run-at-time 2.0 nil 'ignore)))
 919                        (if (featurep 'xemacs)
 920                            (lambda (process state)
 921                              (when (eq 'exit (process-status process))
 922                                (if (memq timer itimer-list)
 923                                    (set-itimer-function timer fn)
 924                                  (funcall fn))
 925                                (ignore-errors (eval fm))
 926                                (message "%s" done)))
 927                          (lambda (process state)
 928                            (when (eq 'exit (process-status process))
 929                              (if (memq timer timer-list)
 930                                  (timer-set-function timer fn)
 931                                (funcall fn))
 932                              (ignore-errors (eval fm))
 933                              (message "%s" done)))))))
 934                 (mm-handle-set-external-undisplayer
 935                  handle (cons file buffer)))
 936               (message "Displaying %s..." command))
 937             'external)))))))
 938
 939 (defun mm-mailcap-command (method file type-list)
 940   (let ((ctl (cdr type-list))
 941         (beg 0)
 942         (uses-stdin t)
 943         out sub total)
 944     (while (string-match "%{\\([^}]+\\)}\\|'%s'\\|\"%s\"\\|%s\\|%t\\|%%"
 945                          method beg)
 946       (push (substring method beg (match-beginning 0)) out)
 947       (setq beg (match-end 0)
 948             total (match-string 0 method)
 949             sub (match-string 1 method))
 950       (cond
 951        ((string= total "%%")
 952         (push "%" out))
 953        ((or (string= total "%s")
 954             ;; We do our own quoting.
 955             (string= total "'%s'")
 956             (string= total "\"%s\""))
 957         (setq uses-stdin nil)
 958         (push (shell-quote-argument
 959                (gnus-map-function mm-path-name-rewrite-functions file)) out))
 960        ((string= total "%t")
 961         (push (shell-quote-argument (car type-list)) out))
 962        (t
 963         (push (shell-quote-argument (or (cdr (assq (intern sub) ctl)) "")) out))))
 964     (push (substring method beg (length method)) out)
 965     (when uses-stdin
 966       (push "<" out)
 967       (push (shell-quote-argument
 968              (gnus-map-function mm-path-name-rewrite-functions file))
 969             out))
 970     (mapconcat 'identity (nreverse out) "")))
 971
 972 (defun mm-remove-parts (handles)
 973   "Remove the displayed MIME parts represented by HANDLES."
 974   (if (and (listp handles)
 975            (bufferp (car handles)))
 976       (mm-remove-part handles)
 977     (let (handle)
 978       (while (setq handle (pop handles))
 979         (cond
 980          ((stringp handle)
 981           (when (buffer-live-p (get-text-property 0 'buffer handle))
 982             (kill-buffer (get-text-property 0 'buffer handle))))
 983          ((and (listp handle)
 984                (stringp (car handle)))
 985           (mm-remove-parts (cdr handle)))
 986          (t
 987           (mm-remove-part handle)))))))
 988
 989 (defun mm-destroy-parts (handles)
 990   "Remove the displayed MIME parts represented by HANDLES."
 991   (if (and (listp handles)
 992            (bufferp (car handles)))
 993       (mm-destroy-part handles)
 994     (let (handle)
 995       (while (setq handle (pop handles))
 996         (cond
 997          ((stringp handle)
 998           (when (buffer-live-p (get-text-property 0 'buffer handle))
 999             (kill-buffer (get-text-property 0 'buffer handle))))
1000          ((and (listp handle)
1001                (stringp (car handle)))
1002           (mm-destroy-parts handle))
1003          (t
1004           (mm-destroy-part handle)))))))
1005
1006 (defun mm-remove-part (handle)
1007   "Remove the displayed MIME part represented by HANDLE."
1008   (when (listp handle)
1009     (let ((object (mm-handle-undisplayer handle)))
1010       (ignore-errors
1011         (cond
1012          ;; Internally displayed part.
1013          ((mm-annotationp object)
1014           (if (featurep 'xemacs)
1015               (delete-annotation object)))
1016          ((or (functionp object)
1017               (and (listp object)
1018                    (eq (car object) 'lambda)))
1019           (funcall object))
1020          ;; Externally displayed part.
1021          ((consp object)
1022           (condition-case ()
1023               (while (get-buffer-process (cdr object))
1024                 (interrupt-process (get-buffer-process (cdr object)))
1025                 (message "Waiting for external displayer to die...")
1026                 (sit-for 1))
1027             (quit)
1028             (error))
1029           (ignore-errors (and (cdr object) (kill-buffer (cdr object))))
1030           (message "Waiting for external displayer to die...done")
1031           (ignore-errors (delete-file (car object)))
1032           (ignore-errors (delete-directory (file-name-directory
1033                                             (car object)))))
1034          ((bufferp object)
1035           (when (buffer-live-p object)
1036             (kill-buffer object)))))
1037       (mm-handle-set-undisplayer handle nil))))
1038
1039 (defun mm-display-inline (handle)
1040   (let* ((type (mm-handle-media-type handle))
1041          (function (cadr (mm-assoc-string-match mm-inline-media-tests type))))
1042     (funcall function handle)
1043     (goto-char (point-min))))
1044
1045 (defun mm-assoc-string-match (alist type)
1046   (dolist (elem alist)
1047     (when (string-match (car elem) type)
1048       (return elem))))
1049
1050 (defun mm-automatic-display-p (handle)
1051   "Say whether the user wants HANDLE to be displayed automatically."
1052   (let ((methods mm-automatic-display)
1053         (type (mm-handle-media-type handle))
1054         method result)
1055     (while (setq method (pop methods))
1056       (when (and (not (mm-inline-override-p handle))
1057                  (string-match method type))
1058         (setq result t
1059               methods nil)))
1060     result))
1061
1062 (defun mm-inlinable-p (handle &optional type)
1063   "Say whether HANDLE can be displayed inline.
1064 TYPE is the mime-type of the object; it defaults to the one given
1065 in HANDLE."
1066   (unless type (setq type (mm-handle-media-type handle)))
1067   (let ((alist mm-inline-media-tests)
1068         test)
1069     (while alist
1070       (when (string-match (caar alist) type)
1071         (setq test (caddar alist)
1072               alist nil)
1073         (setq test (funcall test handle)))
1074       (pop alist))
1075     test))
1076
1077 (defun mm-inlined-p (handle)
1078   "Say whether the user wants HANDLE to be displayed inline."
1079   (let ((methods mm-inlined-types)
1080         (type (mm-handle-media-type handle))
1081         method result)
1082     (while (setq method (pop methods))
1083       (when (and (not (mm-inline-override-p handle))
1084                  (string-match method type))
1085         (setq result t
1086               methods nil)))
1087     result))
1088
1089 (defun mm-attachment-override-p (handle)
1090   "Say whether HANDLE should have attachment behavior overridden."
1091   (let ((types mm-attachment-override-types)
1092         (type (mm-handle-media-type handle))
1093         ty)
1094     (catch 'found
1095       (while (setq ty (pop types))
1096         (when (and (string-match ty type)
1097                    (mm-inlinable-p handle))
1098           (throw 'found t))))))
1099
1100 (defun mm-inline-override-p (handle)
1101   "Say whether HANDLE should have inline behavior overridden."
1102   (let ((types mm-inline-override-types)
1103         (type (mm-handle-media-type handle))
1104         ty)
1105     (catch 'found
1106       (while (setq ty (pop types))
1107         (when (string-match ty type)
1108           (throw 'found t))))))
1109
1110 (defun mm-automatic-external-display-p (type)
1111   "Return the user-defined method for TYPE."
1112   (let ((methods mm-automatic-external-display)
1113         method result)
1114     (while (setq method (pop methods))
1115       (when (string-match method type)
1116         (setq result t
1117               methods nil)))
1118     result))
1119
1120 (defun mm-destroy-part (handle)
1121   "Destroy the data structures connected to HANDLE."
1122   (when (listp handle)
1123     (mm-remove-part handle)
1124     (when (buffer-live-p (mm-handle-buffer handle))
1125       (kill-buffer (mm-handle-buffer handle)))))
1126
1127 (defun mm-handle-displayed-p (handle)
1128   "Say whether HANDLE is displayed or not."
1129   (mm-handle-undisplayer handle))
1130
1131 ;;;
1132 ;;; Functions for outputting parts
1133 ;;;
1134
1135 (defmacro mm-with-part (handle &rest forms)
1136   "Run FORMS in the temp buffer containing the contents of HANDLE."
1137   ;; The handle-buffer's content is a sequence of bytes, not a sequence of
1138   ;; chars, so the buffer should be unibyte.  It may happen that the
1139   ;; handle-buffer is multibyte for some reason, in which case now is a good
1140   ;; time to adjust it, since we know at this point that it should
1141   ;; be unibyte.
1142   `(let* ((handle ,handle))
1143      (with-temp-buffer
1144        (mm-disable-multibyte)
1145        (insert-buffer-substring (mm-handle-buffer handle))
1146        (mm-decode-content-transfer-encoding
1147         (mm-handle-encoding handle)
1148         (mm-handle-media-type handle))
1149        ,@forms)))
1150 (put 'mm-with-part 'lisp-indent-function 1)
1151 (put 'mm-with-part 'edebug-form-spec '(body))
1152
1153 (defun mm-get-part (handle &optional no-cache)
1154   "Return the contents of HANDLE as a string.
1155 If NO-CACHE is non-nil, cached contents of a message/external-body part
1156 are ignored."
1157   (if (and (not no-cache)
1158            (equal (mm-handle-media-type handle) "message/external-body"))
1159       (progn
1160         (unless (mm-handle-cache handle)
1161           (mm-extern-cache-contents handle))
1162         (with-current-buffer (mm-handle-buffer (mm-handle-cache handle))
1163           (buffer-string)))
1164     (mm-with-part handle
1165       (buffer-string))))
1166
1167 (defun mm-insert-part (handle &optional no-cache)
1168   "Insert the contents of HANDLE in the current buffer.
1169 If NO-CACHE is non-nil, cached contents of a message/external-body part
1170 are ignored."
1171   (let ((text (cond ((eq (mail-content-type-get (mm-handle-type handle)
1172                                                 'charset)
1173                          'gnus-decoded)
1174                      (with-current-buffer (mm-handle-buffer handle)
1175                        (buffer-string)))
1176                     ((mm-multibyte-p)
1177                      (mm-string-to-multibyte (mm-get-part handle no-cache)))
1178                     (t
1179                      (mm-get-part handle no-cache)))))
1180     (save-restriction
1181       (widen)
1182       (goto-char
1183        (prog1
1184            (point)
1185          (if (and (eq (get-char-property (max (point-min) (1- (point))) 'face)
1186                       'mm-uu-extract)
1187                   (eq (get-char-property 0 'face text) 'mm-uu-extract))
1188              ;; Separate the extracted parts that have the same faces.
1189              (insert "\n" text)
1190            (insert text)))))))
1191
1192 (defun mm-file-name-delete-whitespace (file-name)
1193   "Remove all whitespace characters from FILE-NAME."
1194   (while (string-match "\\s-+" file-name)
1195     (setq file-name (replace-match "" t t file-name)))
1196   file-name)
1197
1198 (defun mm-file-name-trim-whitespace (file-name)
1199   "Remove leading and trailing whitespace characters from FILE-NAME."
1200   (when (string-match "\\`\\s-+" file-name)
1201     (setq file-name (substring file-name (match-end 0))))
1202   (when (string-match "\\s-+\\'" file-name)
1203     (setq file-name (substring file-name 0 (match-beginning 0))))
1204   file-name)
1205
1206 (defun mm-file-name-collapse-whitespace (file-name)
1207   "Collapse multiple whitespace characters in FILE-NAME."
1208   (while (string-match "\\s-\\s-+" file-name)
1209     (setq file-name (replace-match " " t t file-name)))
1210   file-name)
1211
1212 (defun mm-file-name-replace-whitespace (file-name)
1213   "Replace whitespace characters in FILE-NAME with underscores.
1214 Set the option `mm-file-name-replace-whitespace' to any other
1215 string if you do not like underscores."
1216   (let ((s (or mm-file-name-replace-whitespace "_")))
1217     (while (string-match "\\s-" file-name)
1218       (setq file-name (replace-match s t t file-name))))
1219   file-name)
1220
1221 (defun mm-file-name-delete-control (filename)
1222   "Delete control characters from FILENAME."
1223   (gnus-replace-in-string filename "[\x00-\x1f\x7f]" ""))
1224
1225 (defun mm-file-name-delete-gotchas (filename)
1226   "Delete shell gotchas from FILENAME."
1227   (setq filename (gnus-replace-in-string filename "[<>|]" ""))
1228   (gnus-replace-in-string filename "^[.-]+" ""))
1229
1230 (defun mm-save-part (handle &optional prompt)
1231   "Write HANDLE to a file.
1232 PROMPT overrides the default one used to ask user for a file name."
1233   (let ((filename (or (mail-content-type-get
1234                        (mm-handle-disposition handle) 'filename)
1235                       (mail-content-type-get
1236                        (mm-handle-type handle) 'name)))
1237         file)
1238     (when filename
1239       (setq filename (gnus-map-function mm-file-name-rewrite-functions
1240                                         (file-name-nondirectory filename))))
1241     (setq file
1242           (read-file-name (or prompt "Save MIME part to: ")
1243                           (or mm-default-directory default-directory)
1244                           nil nil (or filename "")))
1245     (setq mm-default-directory (file-name-directory file))
1246     (and (or (not (file-exists-p file))
1247              (yes-or-no-p (format "File %s already exists; overwrite? "
1248                                   file)))
1249          (progn
1250            (mm-save-part-to-file handle file)
1251            file))))
1252
1253 (defun mm-add-meta-html-tag (handle &optional charset)
1254   "Add meta html tag to specify CHARSET of HANDLE in the current buffer.
1255 CHARSET defaults to the one HANDLE specifies.  Existing meta tag that
1256 specifies charset will not be modified.  Return t if meta tag is added
1257 or replaced."
1258   (when (equal (mm-handle-media-type handle) "text/html")
1259     (when (or charset
1260               (setq charset (mail-content-type-get (mm-handle-type handle)
1261                                                    'charset)))
1262       (setq charset (format "\
1263 <meta http-equiv=\"Content-Type\" content=\"text/html; charset=%s\">" charset))
1264       (let ((case-fold-search t))
1265         (goto-char (point-min))
1266         (if (re-search-forward "\
1267 <meta\\s-+http-equiv=[\"']?content-type[\"']?\\s-+content=[\"']\
1268 text/\\(\\sw+\\)\\(?:\;\\s-*charset=\\(.+\\)\\)?[\"'][^>]*>" nil t)
1269             (if (and (match-beginning 2)
1270                      (string-match "\\`html\\'" (match-string 1)))
1271                 ;; Don't modify existing meta tag.
1272                 nil
1273               ;; Replace it with the one specifying charset.
1274               (replace-match charset)
1275               t)
1276           (if (re-search-forward "<head>\\s-*" nil t)
1277               (insert charset "\n")
1278             (re-search-forward "<html\\(?:\\s-+[^>]+\\|\\s-*\\)>\\s-*" nil t)
1279             (insert "<head>\n" charset "\n</head>\n"))
1280           t)))))
1281
1282 (defun mm-save-part-to-file (handle file)
1283   (mm-with-unibyte-buffer
1284     (mm-insert-part handle)
1285     (mm-add-meta-html-tag handle)
1286     (let ((current-file-modes (default-file-modes)))
1287       (set-default-file-modes mm-attachment-file-modes)
1288       (unwind-protect
1289           ;; Don't re-compress .gz & al.  Arguably we should make
1290           ;; `file-name-handler-alist' nil, but that would chop
1291           ;; ange-ftp, which is reasonable to use here.
1292           (mm-write-region (point-min) (point-max) file nil nil nil 'binary t)
1293         (set-default-file-modes current-file-modes)))))
1294
1295 (defun mm-pipe-part (handle)
1296   "Pipe HANDLE to a process."
1297   (let* ((name (mail-content-type-get (mm-handle-type handle) 'name))
1298          (command
1299           (gnus-read-shell-command
1300            "Shell command on MIME part: " mm-last-shell-command)))
1301     (mm-with-unibyte-buffer
1302       (mm-insert-part handle)
1303       (mm-add-meta-html-tag handle)
1304       (let ((coding-system-for-write 'binary))
1305         (shell-command-on-region (point-min) (point-max) command nil)))))
1306
1307 (defun mm-interactively-view-part (handle)
1308   "Display HANDLE using METHOD."
1309   (let* ((type (mm-handle-media-type handle))
1310          (methods
1311           (mapcar (lambda (i) (list (cdr (assoc 'viewer i))))
1312                   (mailcap-mime-info type 'all)))
1313          (method (let ((minibuffer-local-completion-map
1314                         mm-viewer-completion-map))
1315                    (completing-read "Viewer: " methods))))
1316     (when (string= method "")
1317       (error "No method given"))
1318     (if (string-match "^[^% \t]+$" method)
1319         (setq method (concat method " %s")))
1320     (mm-display-external handle method)))
1321
1322 (defun mm-preferred-alternative (handles &optional preferred)
1323   "Say which of HANDLES are preferred."
1324   (let ((prec (if preferred (list preferred)
1325                 (mm-preferred-alternative-precedence handles)))
1326         p h result type handle)
1327     (while (setq p (pop prec))
1328       (setq h handles)
1329       (while h
1330         (setq handle (car h))
1331         (setq type (mm-handle-media-type handle))
1332         (when (and (equal p type)
1333                    (mm-automatic-display-p handle)
1334                    (or (stringp (car handle))
1335                        (not (mm-handle-disposition handle))
1336                        (equal (car (mm-handle-disposition handle))
1337                               "inline")))
1338           (setq result handle
1339                 h nil
1340                 prec nil))
1341         (pop h)))
1342     result))
1343
1344 (defun mm-preferred-alternative-precedence (handles)
1345   "Return the precedence based on HANDLES and `mm-discouraged-alternatives'."
1346   (let ((seq (nreverse (mapcar #'mm-handle-media-type
1347                                handles))))
1348     (dolist (disc (reverse mm-discouraged-alternatives))
1349       (dolist (elem (copy-sequence seq))
1350         (when (string-match disc elem)
1351           (setq seq (nconc (delete elem seq) (list elem))))))
1352     seq))
1353
1354 (defun mm-get-content-id (id)
1355   "Return the handle(s) referred to by ID."
1356   (cdr (assoc id mm-content-id-alist)))
1357
1358 (defconst mm-image-type-regexps
1359   '(("/\\*.*XPM.\\*/" . xpm)
1360     ("P[1-6]" . pbm)
1361     ("GIF8" . gif)
1362     ("\377\330" . jpeg)
1363     ("\211PNG\r\n" . png)
1364     ("#define" . xbm)
1365     ("\\(MM\0\\*\\)\\|\\(II\\*\0\\)" . tiff)
1366     ("%!PS" . postscript))
1367   "Alist of (REGEXP . IMAGE-TYPE) pairs used to auto-detect image types.
1368 When the first bytes of an image file match REGEXP, it is assumed to
1369 be of image type IMAGE-TYPE.")
1370
1371 ;; Steal from image.el. image-type-from-data suffers multi-line matching bug.
1372 (defun mm-image-type-from-buffer ()
1373   "Determine the image type from data in the current buffer.
1374 Value is a symbol specifying the image type or nil if type cannot
1375 be determined."
1376   (let ((types mm-image-type-regexps)
1377         type)
1378     (goto-char (point-min))
1379     (while (and types (null type))
1380       (let ((regexp (car (car types)))
1381             (image-type (cdr (car types))))
1382         (when (looking-at regexp)
1383           (setq type image-type))
1384         (setq types (cdr types))))
1385     type))
1386
1387 (defun mm-get-image (handle)
1388   "Return an image instance based on HANDLE."
1389   (let ((type (mm-handle-media-subtype handle))
1390         spec)
1391     ;; Allow some common translations.
1392     (setq type
1393           (cond
1394            ((equal type "x-pixmap")
1395             "xpm")
1396            ((equal type "x-xbitmap")
1397             "xbm")
1398            ((equal type "x-portable-bitmap")
1399             "pbm")
1400            (t type)))
1401     (or (mm-handle-cache handle)
1402         (mm-with-unibyte-buffer
1403           (mm-insert-part handle)
1404           (prog1
1405               (setq spec
1406                     (ignore-errors
1407                       ;; Avoid testing `make-glyph' since W3 may define
1408                       ;; a bogus version of it.
1409                       (if (fboundp 'create-image)
1410                           (create-image (buffer-string)
1411                                         (or (mm-image-type-from-buffer)
1412                                             (intern type))
1413                                         'data-p)
1414                         (mm-create-image-xemacs type))))
1415             (mm-handle-set-cache handle spec))))))
1416
1417 (defun mm-create-image-xemacs (type)
1418   (when (featurep 'xemacs)
1419     (cond
1420      ((equal type "xbm")
1421       ;; xbm images require special handling, since
1422       ;; the only way to create glyphs from these
1423       ;; (without a ton of work) is to write them
1424       ;; out to a file, and then create a file
1425       ;; specifier.
1426       (let ((file (mm-make-temp-file
1427                    (expand-file-name "emm" mm-tmp-directory)
1428                    nil ".xbm")))
1429         (unwind-protect
1430             (progn
1431               (write-region (point-min) (point-max) file)
1432               (make-glyph (list (cons 'x file))))
1433           (ignore-errors
1434             (delete-file file)))))
1435      (t
1436       (make-glyph
1437        (vector
1438         (or (mm-image-type-from-buffer)
1439             (intern type))
1440         :data (buffer-string)))))))
1441
1442 (declare-function image-size "image.c" (spec &optional pixels frame))
1443
1444 (defun mm-image-fit-p (handle)
1445   "Say whether the image in HANDLE will fit the current window."
1446   (let ((image (mm-get-image handle)))
1447     (or (not image)
1448         (if (featurep 'xemacs)
1449             ;; XEmacs' glyphs can actually tell us about their width, so
1450             ;; lets be nice and smart about them.
1451             (or mm-inline-large-images
1452                 (and (<= (glyph-width image) (window-pixel-width))
1453                      (<= (glyph-height image) (window-pixel-height))))
1454           (let* ((size (image-size image))
1455                  (w (car size))
1456                  (h (cdr size)))
1457             (or mm-inline-large-images
1458                 (and (<= h (1- (window-height))) ; Don't include mode line.
1459                      (<= w (window-width)))))))))
1460
1461 (defun mm-valid-image-format-p (format)
1462   "Say whether FORMAT can be displayed natively by Emacs."
1463   (cond
1464    ;; Handle XEmacs
1465    ((fboundp 'valid-image-instantiator-format-p)
1466     (valid-image-instantiator-format-p format))
1467    ;; Handle Emacs 21
1468    ((fboundp 'image-type-available-p)
1469     (and (display-graphic-p)
1470          (image-type-available-p format)))
1471    ;; Nobody else can do images yet.
1472    (t
1473     nil)))
1474
1475 (defun mm-valid-and-fit-image-p (format handle)
1476   "Say whether FORMAT can be displayed natively and HANDLE fits the window."
1477   (and (mm-valid-image-format-p format)
1478        (mm-image-fit-p handle)))
1479
1480 (defun mm-find-part-by-type (handles type &optional notp recursive)
1481   "Search in HANDLES for part with TYPE.
1482 If NOTP, returns first non-matching part.
1483 If RECURSIVE, search recursively."
1484   (let (handle)
1485     (while handles
1486       (if (and recursive (stringp (caar handles)))
1487           (if (setq handle (mm-find-part-by-type (cdar handles) type
1488                                                  notp recursive))
1489               (setq handles nil))
1490         (if (if notp
1491                 (not (equal (mm-handle-media-type (car handles)) type))
1492               (equal (mm-handle-media-type (car handles)) type))
1493             (setq handle (car handles)
1494                   handles nil)))
1495       (setq handles (cdr handles)))
1496     handle))
1497
1498 (defun mm-find-raw-part-by-type (ctl type &optional notp)
1499   (goto-char (point-min))
1500   (let* ((boundary (concat "--" (mm-handle-multipart-ctl-parameter ctl
1501                                                                    'boundary)))
1502          (close-delimiter (concat "^" (regexp-quote boundary) "--[ \t]*$"))
1503          start
1504          (end (save-excursion
1505                 (goto-char (point-max))
1506                 (if (re-search-backward close-delimiter nil t)
1507                     (match-beginning 0)
1508                   (point-max))))
1509          result)
1510     (setq boundary (concat "^" (regexp-quote boundary) "[ \t]*$"))
1511     (while (and (not result)
1512                 (re-search-forward boundary end t))
1513       (goto-char (match-beginning 0))
1514       (when start
1515         (save-excursion
1516           (save-restriction
1517             (narrow-to-region start (1- (point)))
1518             (when (let* ((ct (mail-fetch-field "content-type"))
1519                          (ctl (and ct (mail-header-parse-content-type ct))))
1520                     (if notp
1521                         (not (equal (car ctl) type))
1522                       (equal (car ctl) type)))
1523               (setq result (buffer-string))))))
1524       (forward-line 1)
1525       (setq start (point)))
1526     (when (and (not result) start)
1527       (save-excursion
1528         (save-restriction
1529           (narrow-to-region start end)
1530           (when (let* ((ct (mail-fetch-field "content-type"))
1531                        (ctl (and ct (mail-header-parse-content-type ct))))
1532                   (if notp
1533                       (not (equal (car ctl) type))
1534                     (equal (car ctl) type)))
1535             (setq result (buffer-string))))))
1536     result))
1537
1538 (defvar mm-security-handle nil)
1539
1540 (defsubst mm-set-handle-multipart-parameter (handle parameter value)
1541   ;; HANDLE could be a CTL.
1542   (when handle
1543     (put-text-property 0 (length (car handle)) parameter value
1544                        (car handle))))
1545
1546 (autoload 'mm-view-pkcs7 "mm-view")
1547
1548 (defun mm-possibly-verify-or-decrypt (parts ctl)
1549   (let ((type (car ctl))
1550         (subtype (cadr (split-string (car ctl) "/")))
1551         (mm-security-handle ctl) ;; (car CTL) is the type.
1552         protocol func functest)
1553     (cond
1554      ((or (equal type "application/x-pkcs7-mime")
1555           (equal type "application/pkcs7-mime"))
1556       (with-temp-buffer
1557         (when (and (cond
1558                     ((eq mm-decrypt-option 'never) nil)
1559                     ((eq mm-decrypt-option 'always) t)
1560                     ((eq mm-decrypt-option 'known) t)
1561                     (t (y-or-n-p
1562                         (format "Decrypt (S/MIME) part? "))))
1563                    (mm-view-pkcs7 parts))
1564           (setq parts (mm-dissect-buffer t)))))
1565      ((equal subtype "signed")
1566       (unless (and (setq protocol
1567                          (mm-handle-multipart-ctl-parameter ctl 'protocol))
1568                    (not (equal protocol "multipart/mixed")))
1569         ;; The message is broken or draft-ietf-openpgp-multsig-01.
1570         (let ((protocols mm-verify-function-alist))
1571           (while protocols
1572             (if (and (or (not (setq functest (nth 3 (car protocols))))
1573                          (funcall functest parts ctl))
1574                      (mm-find-part-by-type parts (caar protocols) nil t))
1575                 (setq protocol (caar protocols)
1576                       protocols nil)
1577               (setq protocols (cdr protocols))))))
1578       (setq func (nth 1 (assoc protocol mm-verify-function-alist)))
1579       (when (cond
1580              ((eq mm-verify-option 'never) nil)
1581              ((eq mm-verify-option 'always) t)
1582              ((eq mm-verify-option 'known)
1583               (and func
1584                    (or (not (setq functest
1585                                   (nth 3 (assoc protocol
1586                                                 mm-verify-function-alist))))
1587                        (funcall functest parts ctl))))
1588              (t
1589               (y-or-n-p
1590                (format "Verify signed (%s) part? "
1591                        (or (nth 2 (assoc protocol mm-verify-function-alist))
1592                            (format "protocol=%s" protocol))))))
1593         (save-excursion
1594           (if func
1595               (setq parts (funcall func parts ctl))
1596             (mm-set-handle-multipart-parameter
1597              mm-security-handle 'gnus-details
1598              (format "Unknown sign protocol (%s)" protocol))))))
1599      ((equal subtype "encrypted")
1600       (unless (setq protocol
1601                     (mm-handle-multipart-ctl-parameter ctl 'protocol))
1602         ;; The message is broken.
1603         (let ((parts parts))
1604           (while parts
1605             (if (assoc (mm-handle-media-type (car parts))
1606                        mm-decrypt-function-alist)
1607                 (setq protocol (mm-handle-media-type (car parts))
1608                       parts nil)
1609               (setq parts (cdr parts))))))
1610       (setq func (nth 1 (assoc protocol mm-decrypt-function-alist)))
1611       (when (cond
1612              ((eq mm-decrypt-option 'never) nil)
1613              ((eq mm-decrypt-option 'always) t)
1614              ((eq mm-decrypt-option 'known)
1615               (and func
1616                    (or (not (setq functest
1617                                   (nth 3 (assoc protocol
1618                                                 mm-decrypt-function-alist))))
1619                        (funcall functest parts ctl))))
1620              (t
1621               (y-or-n-p
1622                (format "Decrypt (%s) part? "
1623                        (or (nth 2 (assoc protocol mm-decrypt-function-alist))
1624                            (format "protocol=%s" protocol))))))
1625         (save-excursion
1626           (if func
1627               (setq parts (funcall func parts ctl))
1628             (mm-set-handle-multipart-parameter
1629              mm-security-handle 'gnus-details
1630              (format "Unknown encrypt protocol (%s)" protocol))))))
1631      (t nil))
1632     parts))
1633
1634 (defun mm-multiple-handles (handles)
1635   (and (listp handles)
1636        (> (length handles) 1)
1637        (or (listp (car handles))
1638            (stringp (car handles)))))
1639
1640 (defun mm-complicated-handles (handles)
1641   (and (listp (car handles))
1642        (> (length handles) 1)))
1643
1644 (defun mm-merge-handles (handles1 handles2)
1645   (append
1646    (if (listp (car handles1))
1647        handles1
1648      (list handles1))
1649    (if (listp (car handles2))
1650        handles2
1651      (list handles2))))
1652
1653 (defun mm-readable-p (handle)
1654   "Say whether the content of HANDLE is readable."
1655   (and (< (with-current-buffer (mm-handle-buffer handle)
1656             (buffer-size)) 10000)
1657        (mm-with-unibyte-buffer
1658          (mm-insert-part handle)
1659          (and (eq (mm-body-7-or-8) '7bit)
1660               (not (mm-long-lines-p 76))))))
1661
1662 (provide 'mm-decode)
1663
1664 ;; arch-tag: 4f35d360-56b8-4030-9388-3ed82d359b9b
1665 ;;; mm-decode.el ends here