lisp/gnus/mailcap.el

   1 ;;; mailcap.el --- MIME media types configuration
   2
   3 ;; Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   4 ;;   2005 Free Software Foundation, Inc.
   5
   6 ;; Author: William M. Perry <wmperry@aventail.com>
   7 ;;      Lars Magne Ingebrigtsen <larsi@gnus.org>
   8 ;; Keywords: news, mail, multimedia
   9
  10 ;; This file is part of GNU Emacs.
  11
  12 ;; GNU Emacs is free software; you can redistribute it and/or modify
  13 ;; it under the terms of the GNU General Public License as published by
  14 ;; the Free Software Foundation; either version 2, or (at your option)
  15 ;; any later version.
  16
  17 ;; GNU Emacs is distributed in the hope that it will be useful,
  18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ;; GNU General Public License for more details.
  21
  22 ;; You should have received a copy of the GNU General Public License
  23 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  24 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  25 ;; Boston, MA 02110-1301, USA.
  26
  27 ;;; Commentary:
  28
  29 ;; Provides configuration of MIME media types from directly from Lisp
  30 ;; and via the usual mailcap mechanism (RFC 1524).  Deals with
  31 ;; mime.types similarly.
  32
  33 ;;; Code:
  34
  35 (eval-when-compile (require 'cl))
  36 (require 'mail-parse)
  37 (require 'mm-util)
  38
  39 (defgroup mailcap nil
  40   "Definition of viewers for MIME types."
  41   :version "21.1"
  42   :group 'mime)
  43
  44 (defvar mailcap-parse-args-syntax-table
  45   (let ((table (copy-syntax-table emacs-lisp-mode-syntax-table)))
  46     (modify-syntax-entry ?' "\"" table)
  47     (modify-syntax-entry ?` "\"" table)
  48     (modify-syntax-entry ?{ "(" table)
  49     (modify-syntax-entry ?} ")" table)
  50     table)
  51   "A syntax table for parsing SGML attributes.")
  52
  53 (eval-and-compile
  54   (when (featurep 'xemacs)
  55     (condition-case nil
  56         (require 'lpr)
  57       (error nil))))
  58
  59 (defvar mailcap-print-command
  60   (mapconcat 'identity
  61              (cons (if (boundp 'lpr-command)
  62                        lpr-command
  63                      "lpr")
  64                    (when (boundp 'lpr-switches)
  65                      (if (stringp lpr-switches)
  66                          (list lpr-switches)
  67                        lpr-switches)))
  68              " ")
  69   "Shell command (including switches) used to print Postscript files.")
  70
  71 ;; Postpone using defcustom for this as it's so big and we essentially
  72 ;; have to have two copies of the data around then.  Perhaps just
  73 ;; customize the Lisp viewers and rely on the normal configuration
  74 ;; files for the rest?  -- fx
  75 (defvar mailcap-mime-data
  76   `(("application"
  77      ("vnd.ms-excel"
  78       (viewer . "gnumeric %s")
  79       (test   . (getenv "DISPLAY"))
  80       (type . "application/vnd.ms-excel"))
  81      ("x-x509-ca-cert"
  82       (viewer . ssl-view-site-cert)
  83       (test . (fboundp 'ssl-view-site-cert))
  84       (type . "application/x-x509-ca-cert"))
  85      ("x-x509-user-cert"
  86       (viewer . ssl-view-user-cert)
  87       (test . (fboundp 'ssl-view-user-cert))
  88       (type . "application/x-x509-user-cert"))
  89      ("octet-stream"
  90       (viewer . mailcap-save-binary-file)
  91       (non-viewer . t)
  92       (type . "application/octet-stream"))
  93      ("dvi"
  94       (viewer . "xdvi -safer %s")
  95       (test   . (eq window-system 'x))
  96       ("needsx11")
  97       (type   . "application/dvi")
  98       ("print" . "dvips -qRP %s"))
  99      ("dvi"
 100       (viewer . "dvitty %s")
 101       (test   . (not (getenv "DISPLAY")))
 102       (type   . "application/dvi")
 103       ("print" . "dvips -qRP %s"))
 104      ("emacs-lisp"
 105       (viewer . mailcap-maybe-eval)
 106       (type   . "application/emacs-lisp"))
 107      ("x-emacs-lisp"
 108       (viewer . mailcap-maybe-eval)
 109       (type   . "application/x-emacs-lisp"))
 110      ("x-tar"
 111       (viewer . mailcap-save-binary-file)
 112       (non-viewer . t)
 113       (type   . "application/x-tar"))
 114      ("x-latex"
 115       (viewer . tex-mode)
 116       (test   . (fboundp 'tex-mode))
 117       (type   . "application/x-latex"))
 118      ("x-tex"
 119       (viewer . tex-mode)
 120       (test   . (fboundp 'tex-mode))
 121       (type   . "application/x-tex"))
 122      ("latex"
 123       (viewer . tex-mode)
 124       (test   . (fboundp 'tex-mode))
 125       (type   . "application/latex"))
 126      ("tex"
 127       (viewer . tex-mode)
 128       (test   . (fboundp 'tex-mode))
 129       (type   . "application/tex"))
 130      ("texinfo"
 131       (viewer . texinfo-mode)
 132       (test   . (fboundp 'texinfo-mode))
 133       (type   . "application/tex"))
 134      ("zip"
 135       (viewer . mailcap-save-binary-file)
 136       (non-viewer . t)
 137       (type   . "application/zip")
 138       ("copiousoutput"))
 139      ("pdf"
 140       (viewer . "gv -safer %s")
 141       (type . "application/pdf")
 142       (test . window-system)
 143       ("print" . ,(concat "pdf2ps %s - | " mailcap-print-command)))
 144      ("pdf"
 145       (viewer . "gpdf %s")
 146       (type . "application/pdf")
 147       ("print" . ,(concat "pdftops %s - | " mailcap-print-command))
 148       (test . (eq window-system 'x)))
 149      ("pdf"
 150       (viewer . "xpdf %s")
 151       (type . "application/pdf")
 152       ("print" . ,(concat "pdftops %s - | " mailcap-print-command))
 153       (test . (eq window-system 'x)))
 154      ("pdf"
 155       (viewer . ,(concat "pdftotext %s -"))
 156       (type   . "application/pdf")
 157       ("print" . ,(concat "pdftops %s - | " mailcap-print-command))
 158       ("copiousoutput"))
 159      ("postscript"
 160       (viewer . "gv -safer %s")
 161       (type . "application/postscript")
 162       (test   . window-system)
 163       ("print" . ,(concat mailcap-print-command " %s"))
 164       ("needsx11"))
 165      ("postscript"
 166       (viewer . "ghostview -dSAFER %s")
 167       (type . "application/postscript")
 168       (test   . (eq window-system 'x))
 169       ("print" . ,(concat mailcap-print-command " %s"))
 170       ("needsx11"))
 171      ("postscript"
 172       (viewer . "ps2ascii %s")
 173       (type . "application/postscript")
 174       (test . (not (getenv "DISPLAY")))
 175       ("print" . ,(concat mailcap-print-command " %s"))
 176       ("copiousoutput"))
 177      ("sieve"
 178       (viewer . sieve-mode)
 179       (test   . (fboundp 'sieve-mode))
 180       (type   . "application/sieve"))
 181      ("pgp-keys"
 182       (viewer . "gpg --import --interactive --verbose")
 183       (type   . "application/pgp-keys")
 184       ("needsterminal")))
 185     ("audio"
 186      ("x-mpeg"
 187       (viewer . "maplay %s")
 188       (type   . "audio/x-mpeg"))
 189      (".*"
 190       (viewer . "showaudio")
 191       (type   . "audio/*")))
 192     ("message"
 193      ("rfc-*822"
 194       (viewer . mm-view-message)
 195       (test   . (and (featurep 'gnus)
 196                      (gnus-alive-p)))
 197       (type   . "message/rfc822"))
 198      ("rfc-*822"
 199       (viewer . vm-mode)
 200       (test   . (fboundp 'vm-mode))
 201       (type   . "message/rfc822"))
 202      ("rfc-*822"
 203       (viewer . w3-mode)
 204       (test   . (fboundp 'w3-mode))
 205       (type   . "message/rfc822"))
 206      ("rfc-*822"
 207       (viewer . view-mode)
 208       (type   . "message/rfc822")))
 209     ("image"
 210      ("x-xwd"
 211       (viewer  . "xwud -in %s")
 212       (type    . "image/x-xwd")
 213       ("compose" . "xwd -frame > %s")
 214       (test    . (eq window-system 'x))
 215       ("needsx11"))
 216      ("x11-dump"
 217       (viewer . "xwud -in %s")
 218       (type . "image/x-xwd")
 219       ("compose" . "xwd -frame > %s")
 220       (test   . (eq window-system 'x))
 221       ("needsx11"))
 222      ("windowdump"
 223       (viewer . "xwud -in %s")
 224       (type . "image/x-xwd")
 225       ("compose" . "xwd -frame > %s")
 226       (test   . (eq window-system 'x))
 227       ("needsx11"))
 228      (".*"
 229       (viewer . "display %s")
 230       (type . "image/*")
 231       (test   . (eq window-system 'x))
 232       ("needsx11"))
 233      (".*"
 234       (viewer . "ee %s")
 235       (type . "image/*")
 236       (test   . (eq window-system 'x))
 237       ("needsx11")))
 238     ("text"
 239      ("plain"
 240       (viewer  . w3-mode)
 241       (test    . (fboundp 'w3-mode))
 242       (type    . "text/plain"))
 243      ("plain"
 244       (viewer  . view-mode)
 245       (test    . (fboundp 'view-mode))
 246       (type    . "text/plain"))
 247      ("plain"
 248       (viewer  . fundamental-mode)
 249       (type    . "text/plain"))
 250      ("enriched"
 251       (viewer . enriched-decode)
 252       (test   . (fboundp 'enriched-decode))
 253       (type   . "text/enriched"))
 254      ("html"
 255       (viewer . mm-w3-prepare-buffer)
 256       (test   . (fboundp 'w3-prepare-buffer))
 257       (type   . "text/html")))
 258     ("video"
 259      ("mpeg"
 260       (viewer . "mpeg_play %s")
 261       (type   . "video/mpeg")
 262       (test   . (eq window-system 'x))
 263       ("needsx11")))
 264     ("x-world"
 265      ("x-vrml"
 266       (viewer  . "webspace -remote %s -URL %u")
 267       (type    . "x-world/x-vrml")
 268       ("description"
 269        "VRML document")))
 270     ("archive"
 271      ("tar"
 272       (viewer . tar-mode)
 273       (type . "archive/tar")
 274       (test . (fboundp 'tar-mode)))))
 275   "The mailcap structure is an assoc list of assoc lists.
 276 1st assoc list is keyed on the major content-type
 277 2nd assoc list is keyed on the minor content-type (which can be a regexp)
 278
 279 Which looks like:
 280 -----------------
 281  ((\"application\"
 282    (\"postscript\" . <info>))
 283   (\"text\"
 284    (\"plain\" . <info>)))
 285
 286 Where <info> is another assoc list of the various information
 287 related to the mailcap RFC 1524.  This is keyed on the lowercase
 288 attribute name (viewer, test, etc).  This looks like:
 289  ((viewer . VIEWERINFO)
 290   (test   . TESTINFO)
 291   (xxxx   . \"STRING\")
 292   FLAG)
 293
 294 Where VIEWERINFO specifies how the content-type is viewed.  Can be
 295 a string, in which case it is run through a shell, with
 296 appropriate parameters, or a symbol, in which case the symbol is
 297 `funcall'ed, with the buffer as an argument.
 298
 299 TESTINFO is a test for the viewer's applicability, or nil.  If nil, it
 300 means the viewer is always valid.  If it is a Lisp function, it is
 301 called with a list of items from any extra fields from the
 302 Content-Type header as argument to return a boolean value for the
 303 validity.  Otherwise, if it is a non-function Lisp symbol or list
 304 whose car is a symbol, it is `eval'led to yield the validity.  If it
 305 is a string or list of strings, it represents a shell command to run
 306 to return a true or false shell value for the validity.")
 307 (put 'mailcap-mime-data 'risky-local-variable t)
 308
 309 (defcustom mailcap-download-directory nil
 310   "*Directory to which `mailcap-save-binary-file' downloads files by default.
 311 nil means your home directory."
 312   :type '(choice (const :tag "Home directory" nil)
 313                  directory)
 314   :group 'mailcap)
 315
 316 (defvar mailcap-poor-system-types
 317   '(ms-dos ms-windows windows-nt win32 w32 mswindows)
 318   "Systems that don't have a Unix-like directory hierarchy.")
 319
 320 ;;;
 321 ;;; Utility functions
 322 ;;;
 323
 324 (defun mailcap-save-binary-file ()
 325   (goto-char (point-min))
 326   (unwind-protect
 327       (let ((file (read-file-name
 328                    "Filename to save as: "
 329                    (or mailcap-download-directory "~/")))
 330             (require-final-newline nil))
 331         (write-region (point-min) (point-max) file))
 332     (kill-buffer (current-buffer))))
 333
 334 (defvar mailcap-maybe-eval-warning
 335   "*** WARNING ***
 336
 337 This MIME part contains untrusted and possibly harmful content.
 338 If you evaluate the Emacs Lisp code contained in it, a lot of nasty
 339 things can happen.  Please examine the code very carefully before you
 340 instruct Emacs to evaluate it.  You can browse the buffer containing
 341 the code using \\[scroll-other-window].
 342
 343 If you are unsure what to do, please answer \"no\"."
 344   "Text of warning message displayed by `mailcap-maybe-eval'.
 345 Make sure that this text consists only of few text lines.  Otherwise,
 346 Gnus might fail to display all of it.")
 347
 348 (defun mailcap-maybe-eval ()
 349   "Maybe evaluate a buffer of Emacs Lisp code."
 350   (let ((lisp-buffer (current-buffer)))
 351     (goto-char (point-min))
 352     (when
 353         (save-window-excursion
 354           (delete-other-windows)
 355           (let ((buffer (get-buffer-create (generate-new-buffer-name
 356                                             "*Warning*"))))
 357             (unwind-protect
 358                 (with-current-buffer buffer
 359                   (insert (substitute-command-keys
 360                            mailcap-maybe-eval-warning))
 361                   (goto-char (point-min))
 362                   (display-buffer buffer)
 363                   (yes-or-no-p "This is potentially dangerous emacs-lisp code, evaluate it? "))
 364               (kill-buffer buffer))))
 365       (eval-buffer (current-buffer)))
 366     (when (buffer-live-p lisp-buffer)
 367       (with-current-buffer lisp-buffer
 368         (emacs-lisp-mode)))))
 369
 370
 371 ;;;
 372 ;;; The mailcap parser
 373 ;;;
 374
 375 (defun mailcap-replace-regexp (regexp to-string)
 376   ;; Quiet replace-regexp.
 377   (goto-char (point-min))
 378   (while (re-search-forward regexp nil t)
 379     (replace-match to-string t nil)))
 380
 381 (defvar mailcap-parsed-p nil)
 382
 383 (defun mailcap-parse-mailcaps (&optional path force)
 384   "Parse out all the mailcaps specified in a path string PATH.
 385 Components of PATH are separated by the `path-separator' character
 386 appropriate for this system.  If FORCE, re-parse even if already
 387 parsed.  If PATH is omitted, use the value of environment variable
 388 MAILCAPS if set; otherwise (on Unix) use the path from RFC 1524, plus
 389 /usr/local/etc/mailcap."
 390   (interactive (list nil t))
 391   (when (or (not mailcap-parsed-p)
 392             force)
 393     (cond
 394      (path nil)
 395      ((getenv "MAILCAPS") (setq path (getenv "MAILCAPS")))
 396      ((memq system-type mailcap-poor-system-types)
 397       (setq path '("~/.mailcap" "~/mail.cap" "~/etc/mail.cap")))
 398      (t (setq path
 399               ;; This is per RFC 1524, specifically
 400               ;; with /usr before /usr/local.
 401               '("~/.mailcap" "/etc/mailcap" "/usr/etc/mailcap"
 402                 "/usr/local/etc/mailcap"))))
 403     (let ((fnames (reverse
 404                    (if (stringp path)
 405                        (delete "" (split-string path path-separator))
 406                      path)))
 407           fname)
 408       (while fnames
 409         (setq fname (car fnames))
 410         (if (and (file-readable-p fname)
 411                  (file-regular-p fname))
 412             (mailcap-parse-mailcap fname))
 413         (setq fnames (cdr fnames))))
 414       (setq mailcap-parsed-p t)))
 415
 416 (defun mailcap-parse-mailcap (fname)
 417   "Parse out the mailcap file specified by FNAME."
 418   (let (major                           ; The major mime type (image/audio/etc)
 419         minor                           ; The minor mime type (gif, basic, etc)
 420         save-pos                        ; Misc saved positions used in parsing
 421         viewer                          ; How to view this mime type
 422         info                            ; Misc info about this mime type
 423         )
 424     (with-temp-buffer
 425       (insert-file-contents fname)
 426       (set-syntax-table mailcap-parse-args-syntax-table)
 427       (mailcap-replace-regexp "#.*" "") ; Remove all comments
 428       (mailcap-replace-regexp "\\\\[ \t]*\n" " ") ; And collapse spaces
 429       (mailcap-replace-regexp "\n+" "\n") ; And blank lines
 430       (goto-char (point-max))
 431       (skip-chars-backward " \t\n")
 432       (delete-region (point) (point-max))
 433       (while (not (bobp))
 434         (skip-chars-backward " \t\n")
 435         (beginning-of-line)
 436         (setq save-pos (point)
 437               info nil)
 438         (skip-chars-forward "^/; \t\n")
 439         (downcase-region save-pos (point))
 440         (setq major (buffer-substring save-pos (point)))
 441         (skip-chars-forward " \t")
 442         (setq minor "")
 443         (when (eq (char-after) ?/)
 444           (forward-char)
 445           (skip-chars-forward " \t")
 446           (setq save-pos (point))
 447           (skip-chars-forward "^; \t\n")
 448           (downcase-region save-pos (point))
 449           (setq minor
 450                 (cond
 451                  ((eq ?* (or (char-after save-pos) 0)) ".*")
 452                  ((= (point) save-pos) ".*")
 453                  (t (regexp-quote (buffer-substring save-pos (point)))))))
 454         (skip-chars-forward " \t")
 455         ;;; Got the major/minor chunks, now for the viewers/etc
 456         ;;; The first item _must_ be a viewer, according to the
 457         ;;; RFC for mailcap files (#1524)
 458         (setq viewer "")
 459         (when (eq (char-after) ?\;)
 460           (forward-char)
 461           (skip-chars-forward " \t")
 462           (setq save-pos (point))
 463           (skip-chars-forward "^;\n")
 464           ;; skip \;
 465           (while (eq (char-before) ?\\)
 466             (backward-delete-char 1)
 467             (forward-char)
 468             (skip-chars-forward "^;\n"))
 469           (if (eq (or (char-after save-pos) 0) ?')
 470               (setq viewer (progn
 471                              (narrow-to-region (1+ save-pos) (point))
 472                              (goto-char (point-min))
 473                              (prog1
 474                                  (read (current-buffer))
 475                                (goto-char (point-max))
 476                                (widen))))
 477             (setq viewer (buffer-substring save-pos (point)))))
 478         (setq save-pos (point))
 479         (end-of-line)
 480         (unless (equal viewer "")
 481           (setq info (nconc (list (cons 'viewer viewer)
 482                                   (cons 'type (concat major "/"
 483                                                       (if (string= minor ".*")
 484                                                           "*" minor))))
 485                             (mailcap-parse-mailcap-extras save-pos (point))))
 486           (mailcap-mailcap-entry-passes-test info)
 487           (mailcap-add-mailcap-entry major minor info))
 488         (beginning-of-line)))))
 489
 490 (defun mailcap-parse-mailcap-extras (st nd)
 491   "Grab all the extra stuff from a mailcap entry."
 492   (let (
 493         name                            ; From name=
 494         value                           ; its value
 495         results                         ; Assoc list of results
 496         name-pos                        ; Start of XXXX= position
 497         val-pos                         ; Start of value position
 498         done                            ; Found end of \'d ;s?
 499         )
 500     (save-restriction
 501       (narrow-to-region st nd)
 502       (goto-char (point-min))
 503       (skip-chars-forward " \n\t;")
 504       (while (not (eobp))
 505         (setq done nil)
 506         (setq name-pos (point))
 507         (skip-chars-forward "^ \n\t=;")
 508         (downcase-region name-pos (point))
 509         (setq name (buffer-substring name-pos (point)))
 510         (skip-chars-forward " \t\n")
 511         (if (not (eq (char-after (point)) ?=)) ; There is no value
 512             (setq value t)
 513           (skip-chars-forward " \t\n=")
 514           (setq val-pos (point))
 515           (if (memq (char-after val-pos) '(?\" ?'))
 516               (progn
 517                 (setq val-pos (1+ val-pos))
 518                 (condition-case nil
 519                     (progn
 520                       (forward-sexp 1)
 521                       (backward-char 1))
 522                   (error (goto-char (point-max)))))
 523             (while (not done)
 524               (skip-chars-forward "^;")
 525               (if (eq (char-after (1- (point))) ?\\ )
 526                   (progn
 527                     (subst-char-in-region (1- (point)) (point) ?\\ ? )
 528                     (skip-chars-forward ";"))
 529                 (setq done t))))
 530           (setq value (buffer-substring val-pos (point))))
 531         (setq results (cons (cons name value) results))
 532         (skip-chars-forward " \";\n\t"))
 533       results)))
 534
 535 (defun mailcap-mailcap-entry-passes-test (info)
 536   "Return non-nil iff mailcap entry INFO passes its test clause.
 537 Also return non-nil if no test clause is present."
 538   (let ((test (assq 'test info))        ; The test clause
 539         status)
 540     (setq status (and test (split-string (cdr test) " ")))
 541     (if (and (or (assoc "needsterm" info)
 542                  (assoc "needsterminal" info)
 543                  (assoc "needsx11" info))
 544              (not (getenv "DISPLAY")))
 545         (setq status nil)
 546       (cond
 547        ((and (equal (nth 0 status) "test")
 548              (equal (nth 1 status) "-n")
 549              (or (equal (nth 2 status) "$DISPLAY")
 550                  (equal (nth 2 status) "\"$DISPLAY\"")))
 551         (setq status (if (getenv "DISPLAY") t nil)))
 552        ((and (equal (nth 0 status) "test")
 553              (equal (nth 1 status) "-z")
 554              (or (equal (nth 2 status) "$DISPLAY")
 555                  (equal (nth 2 status) "\"$DISPLAY\"")))
 556         (setq status (if (getenv "DISPLAY") nil t)))
 557        (test nil)
 558        (t nil)))
 559     (and test (listp test) (setcdr test status))))
 560
 561 ;;;
 562 ;;; The action routines.
 563 ;;;
 564
 565 (defun mailcap-possible-viewers (major minor)
 566   "Return a list of possible viewers from MAJOR for minor type MINOR."
 567   (let ((exact '())
 568         (wildcard '()))
 569     (while major
 570       (cond
 571        ((equal (car (car major)) minor)
 572         (setq exact (cons (cdr (car major)) exact)))
 573        ((and minor (string-match (concat "^" (car (car major)) "$") minor))
 574         (setq wildcard (cons (cdr (car major)) wildcard))))
 575       (setq major (cdr major)))
 576     (nconc exact wildcard)))
 577
 578 (defun mailcap-unescape-mime-test (test type-info)
 579   (let (save-pos save-chr subst)
 580     (cond
 581      ((symbolp test) test)
 582      ((and (listp test) (symbolp (car test))) test)
 583      ((or (stringp test)
 584           (and (listp test) (stringp (car test))
 585                (setq test (mapconcat 'identity test " "))))
 586       (with-temp-buffer
 587         (insert test)
 588         (goto-char (point-min))
 589         (while (not (eobp))
 590           (skip-chars-forward "^%")
 591           (if (/= (- (point)
 592                      (progn (skip-chars-backward "\\\\")
 593                             (point)))
 594                   0)                    ; It is an escaped %
 595               (progn
 596                 (delete-char 1)
 597                 (skip-chars-forward "%."))
 598             (setq save-pos (point))
 599             (skip-chars-forward "%")
 600             (setq save-chr (char-after (point)))
 601             ;; Escapes:
 602             ;; %s: name of a file for the body data
 603             ;; %t: content-type
 604             ;; %{<parameter name}: value of parameter in mailcap entry
 605             ;; %n: number of sub-parts for multipart content-type
 606             ;; %F: a set of content-type/filename pairs for multiparts
 607             (cond
 608              ((null save-chr) nil)
 609              ((= save-chr ?t)
 610               (delete-region save-pos (progn (forward-char 1) (point)))
 611               (insert (or (cdr (assq 'type type-info)) "\"\"")))
 612              ((memq save-chr '(?M ?n ?F))
 613               (delete-region save-pos (progn (forward-char 1) (point)))
 614               (insert "\"\""))
 615              ((= save-chr ?{)
 616               (forward-char 1)
 617               (skip-chars-forward "^}")
 618               (downcase-region (+ 2 save-pos) (point))
 619               (setq subst (buffer-substring (+ 2 save-pos) (point)))
 620               (delete-region save-pos (1+ (point)))
 621               (insert (or (cdr (assoc subst type-info)) "\"\"")))
 622              (t nil))))
 623         (buffer-string)))
 624      (t (error "Bad value to mailcap-unescape-mime-test: %s" test)))))
 625
 626 (defvar mailcap-viewer-test-cache nil)
 627
 628 (defun mailcap-viewer-passes-test (viewer-info type-info)
 629   "Return non-nil iff viewer specified by VIEWER-INFO passes its test clause.
 630 Also return non-nil if it has no test clause.  TYPE-INFO is an argument
 631 to supply to the test."
 632   (let* ((test-info (assq 'test viewer-info))
 633          (test (cdr test-info))
 634          (otest test)
 635          (viewer (cdr (assoc 'viewer viewer-info)))
 636          (default-directory (expand-file-name "~/"))
 637          status parsed-test cache result)
 638     (if (setq cache (assoc test mailcap-viewer-test-cache))
 639         (cadr cache)
 640       (setq
 641        result
 642        (cond
 643         ((not test-info) t)             ; No test clause
 644         ((not test) nil)                ; Already failed test
 645         ((eq test t) t)                 ; Already passed test
 646         ((functionp test)               ; Lisp function as test
 647          (funcall test type-info))
 648         ((and (symbolp test)            ; Lisp variable as test
 649               (boundp test))
 650          (symbol-value test))
 651         ((and (listp test)              ; List to be eval'd
 652               (symbolp (car test)))
 653          (eval test))
 654         (t
 655          (setq test (mailcap-unescape-mime-test test type-info)
 656                test (list shell-file-name nil nil nil
 657                           shell-command-switch test)
 658                status (apply 'call-process test))
 659          (eq 0 status))))
 660       (push (list otest result) mailcap-viewer-test-cache)
 661       result)))
 662
 663 (defun mailcap-add-mailcap-entry (major minor info)
 664   (let ((old-major (assoc major mailcap-mime-data)))
 665     (if (null old-major)                ; New major area
 666         (setq mailcap-mime-data
 667               (cons (cons major (list (cons minor info)))
 668                     mailcap-mime-data))
 669       (let ((cur-minor (assoc minor old-major)))
 670         (cond
 671          ((or (null cur-minor)          ; New minor area, or
 672               (assq 'test info))        ; Has a test, insert at beginning
 673           (setcdr old-major (cons (cons minor info) (cdr old-major))))
 674          ((and (not (assq 'test info))  ; No test info, replace completely
 675                (not (assq 'test cur-minor))
 676                (equal (assq 'viewer info)  ; Keep alternative viewer
 677                       (assq 'viewer cur-minor)))
 678           (setcdr cur-minor info))
 679          (t
 680           (setcdr old-major (cons (cons minor info) (cdr old-major))))))
 681       )))
 682
 683 (defun mailcap-add (type viewer &optional test)
 684   "Add VIEWER as a handler for TYPE.
 685 If TEST is not given, it defaults to t."
 686   (let ((tl (split-string type "/")))
 687     (when (or (not (car tl))
 688               (not (cadr tl)))
 689       (error "%s is not a valid MIME type" type))
 690     (mailcap-add-mailcap-entry
 691      (car tl) (cadr tl)
 692      `((viewer . ,viewer)
 693        (test . ,(if test test t))
 694        (type . ,type)))))
 695
 696 ;;;
 697 ;;; The main whabbo
 698 ;;;
 699
 700 (defun mailcap-viewer-lessp (x y)
 701   "Return t iff viewer X is more desirable than viewer Y."
 702   (let ((x-wild (string-match "[*?]" (or (cdr-safe (assq 'type x)) "")))
 703         (y-wild (string-match "[*?]" (or (cdr-safe (assq 'type y)) "")))
 704         (x-lisp (not (stringp (or (cdr-safe (assq 'viewer x)) ""))))
 705         (y-lisp (not (stringp (or (cdr-safe (assq 'viewer y)) "")))))
 706     (cond
 707      ((and x-wild (not y-wild))
 708       nil)
 709      ((and (not x-wild) y-wild)
 710       t)
 711      ((and (not y-lisp) x-lisp)
 712       t)
 713      (t nil))))
 714
 715 (defun mailcap-mime-info (string &optional request)
 716   "Get the MIME viewer command for STRING, return nil if none found.
 717 Expects a complete content-type header line as its argument.
 718
 719 Second argument REQUEST specifies what information to return.  If it is
 720 nil or the empty string, the viewer (second field of the mailcap
 721 entry) will be returned.  If it is a string, then the mailcap field
 722 corresponding to that string will be returned (print, description,
 723 whatever).  If a number, then all the information for this specific
 724 viewer is returned.  If `all', then all possible viewers for
 725 this type is returned."
 726   (let (
 727         major                           ; Major encoding (text, etc)
 728         minor                           ; Minor encoding (html, etc)
 729         info                            ; Other info
 730         save-pos                        ; Misc. position during parse
 731         major-info                      ; (assoc major mailcap-mime-data)
 732         minor-info                      ; (assoc minor major-info)
 733         test                            ; current test proc.
 734         viewers                         ; Possible viewers
 735         passed                          ; Viewers that passed the test
 736         viewer                          ; The one and only viewer
 737         ctl)
 738     (save-excursion
 739       (setq ctl (mail-header-parse-content-type (or string "text/plain")))
 740       (setq major (split-string (car ctl) "/"))
 741       (setq minor (cadr major)
 742             major (car major))
 743       (when (setq major-info (cdr (assoc major mailcap-mime-data)))
 744         (when (setq viewers (mailcap-possible-viewers major-info minor))
 745           (setq info (mapcar (lambda (a) (cons (symbol-name (car a))
 746                                                (cdr a)))
 747                              (cdr ctl)))
 748           (while viewers
 749             (if (mailcap-viewer-passes-test (car viewers) info)
 750                 (setq passed (cons (car viewers) passed)))
 751             (setq viewers (cdr viewers)))
 752           (setq passed (sort passed 'mailcap-viewer-lessp))
 753           (setq viewer (car passed))))
 754       (when (and (stringp (cdr (assq 'viewer viewer)))
 755                  passed)
 756         (setq viewer (car passed)))
 757       (cond
 758        ((and (null viewer) (not (equal major "default")) request)
 759         (mailcap-mime-info "default" request))
 760        ((or (null request) (equal request ""))
 761         (mailcap-unescape-mime-test (cdr (assq 'viewer viewer)) info))
 762        ((stringp request)
 763         (mailcap-unescape-mime-test
 764          (cdr-safe (assoc request viewer)) info))
 765        ((eq request 'all)
 766         passed)
 767        (t
 768         ;; MUST make a copy *sigh*, else we modify mailcap-mime-data
 769         (setq viewer (copy-sequence viewer))
 770         (let ((view (assq 'viewer viewer))
 771               (test (assq 'test viewer)))
 772           (if view (setcdr view (mailcap-unescape-mime-test (cdr view) info)))
 773           (if test (setcdr test (mailcap-unescape-mime-test (cdr test) info))))
 774         viewer)))))
 775
 776 ;;;
 777 ;;; Experimental MIME-types parsing
 778 ;;;
 779
 780 (defvar mailcap-mime-extensions
 781   '((""        . "text/plain")
 782     (".abs"   . "audio/x-mpeg")
 783     (".aif"   . "audio/aiff")
 784     (".aifc"  . "audio/aiff")
 785     (".aiff"  . "audio/aiff")
 786     (".ano"   . "application/x-annotator")
 787     (".au"    . "audio/ulaw")
 788     (".avi"   . "video/x-msvideo")
 789     (".bcpio" . "application/x-bcpio")
 790     (".bin"   . "application/octet-stream")
 791     (".cdf"   . "application/x-netcdr")
 792     (".cpio"  . "application/x-cpio")
 793     (".csh"   . "application/x-csh")
 794     (".css"   . "text/css")
 795     (".dvi"   . "application/x-dvi")
 796     (".diff"  . "text/x-patch")
 797     (".el"    . "application/emacs-lisp")
 798     (".eps"   . "application/postscript")
 799     (".etx"   . "text/x-setext")
 800     (".exe"   . "application/octet-stream")
 801     (".fax"   . "image/x-fax")
 802     (".gif"   . "image/gif")
 803     (".hdf"   . "application/x-hdf")
 804     (".hqx"   . "application/mac-binhex40")
 805     (".htm"   . "text/html")
 806     (".html"  . "text/html")
 807     (".icon"  . "image/x-icon")
 808     (".ief"   . "image/ief")
 809     (".jpg"   . "image/jpeg")
 810     (".macp"  . "image/x-macpaint")
 811     (".man"   . "application/x-troff-man")
 812     (".me"    . "application/x-troff-me")
 813     (".mif"   . "application/mif")
 814     (".mov"   . "video/quicktime")
 815     (".movie" . "video/x-sgi-movie")
 816     (".mp2"   . "audio/x-mpeg")
 817     (".mp3"   . "audio/x-mpeg")
 818     (".mp2a"  . "audio/x-mpeg2")
 819     (".mpa"   . "audio/x-mpeg")
 820     (".mpa2"  . "audio/x-mpeg2")
 821     (".mpe"   . "video/mpeg")
 822     (".mpeg"  . "video/mpeg")
 823     (".mpega" . "audio/x-mpeg")
 824     (".mpegv" . "video/mpeg")
 825     (".mpg"   . "video/mpeg")
 826     (".mpv"   . "video/mpeg")
 827     (".ms"    . "application/x-troff-ms")
 828     (".nc"    . "application/x-netcdf")
 829     (".nc"    . "application/x-netcdf")
 830     (".oda"   . "application/oda")
 831     (".patch" . "text/x-patch")
 832     (".pbm"   . "image/x-portable-bitmap")
 833     (".pdf"   . "application/pdf")
 834     (".pgm"   . "image/portable-graymap")
 835     (".pict"  . "image/pict")
 836     (".png"   . "image/png")
 837     (".pnm"   . "image/x-portable-anymap")
 838     (".ppm"   . "image/portable-pixmap")
 839     (".ps"    . "application/postscript")
 840     (".qt"    . "video/quicktime")
 841     (".ras"   . "image/x-raster")
 842     (".rgb"   . "image/x-rgb")
 843     (".rtf"   . "application/rtf")
 844     (".rtx"   . "text/richtext")
 845     (".sh"    . "application/x-sh")
 846     (".sit"   . "application/x-stuffit")
 847     (".siv"   . "application/sieve")
 848     (".snd"   . "audio/basic")
 849     (".src"   . "application/x-wais-source")
 850     (".tar"   . "archive/tar")
 851     (".tcl"   . "application/x-tcl")
 852     (".tex"   . "application/x-tex")
 853     (".texi"  . "application/texinfo")
 854     (".tga"   . "image/x-targa")
 855     (".tif"   . "image/tiff")
 856     (".tiff"  . "image/tiff")
 857     (".tr"    . "application/x-troff")
 858     (".troff" . "application/x-troff")
 859     (".tsv"   . "text/tab-separated-values")
 860     (".txt"   . "text/plain")
 861     (".vbs"   . "video/mpeg")
 862     (".vox"   . "audio/basic")
 863     (".vrml"  . "x-world/x-vrml")
 864     (".wav"   . "audio/x-wav")
 865     (".xls"   . "application/vnd.ms-excel")
 866     (".wrl"   . "x-world/x-vrml")
 867     (".xbm"   . "image/xbm")
 868     (".xpm"   . "image/xpm")
 869     (".xwd"   . "image/windowdump")
 870     (".zip"   . "application/zip")
 871     (".ai"    . "application/postscript")
 872     (".jpe"   . "image/jpeg")
 873     (".jpeg"  . "image/jpeg"))
 874   "An alist of file extensions and corresponding MIME content-types.
 875 This exists for you to customize the information in Lisp.  It is
 876 merged with values from mailcap files by `mailcap-parse-mimetypes'.")
 877
 878 (defvar mailcap-mimetypes-parsed-p nil)
 879
 880 (defun mailcap-parse-mimetypes (&optional path force)
 881   "Parse out all the mimetypes specified in a Unix-style path string PATH.
 882 Components of PATH are separated by the `path-separator' character
 883 appropriate for this system.  If PATH is omitted, use the value of
 884 environment variable MIMETYPES if set; otherwise use a default path.
 885 If FORCE, re-parse even if already parsed."
 886   (interactive (list nil t))
 887   (when (or (not mailcap-mimetypes-parsed-p)
 888             force)
 889     (cond
 890      (path nil)
 891      ((getenv "MIMETYPES") (setq path (getenv "MIMETYPES")))
 892      ((memq system-type mailcap-poor-system-types)
 893       (setq path '("~/mime.typ" "~/etc/mime.typ")))
 894      (t (setq path
 895               ;; mime.types seems to be the normal name, definitely so
 896               ;; on current GNUish systems.  The search order follows
 897               ;; that for mailcap.
 898               '("~/.mime.types"
 899                 "/etc/mime.types"
 900                 "/usr/etc/mime.types"
 901                 "/usr/local/etc/mime.types"
 902                 "/usr/local/www/conf/mime.types"
 903                 "~/.mime-types"
 904                 "/etc/mime-types"
 905                 "/usr/etc/mime-types"
 906                 "/usr/local/etc/mime-types"
 907                 "/usr/local/www/conf/mime-types"))))
 908     (let ((fnames (reverse (if (stringp path)
 909                                (delete "" (split-string path path-separator))
 910                              path)))
 911           fname)
 912       (while fnames
 913         (setq fname (car fnames))
 914         (if (and (file-readable-p fname))
 915             (mailcap-parse-mimetype-file fname))
 916         (setq fnames (cdr fnames))))
 917     (setq mailcap-mimetypes-parsed-p t)))
 918
 919 (defun mailcap-parse-mimetype-file (fname)
 920   "Parse out a mime-types file FNAME."
 921   (let (type                            ; The MIME type for this line
 922         extns                           ; The extensions for this line
 923         save-pos                        ; Misc. saved buffer positions
 924         )
 925     (with-temp-buffer
 926       (insert-file-contents fname)
 927       (mailcap-replace-regexp "#.*" "")
 928       (mailcap-replace-regexp "\n+" "\n")
 929       (mailcap-replace-regexp "[ \t]+$" "")
 930       (goto-char (point-max))
 931       (skip-chars-backward " \t\n")
 932       (delete-region (point) (point-max))
 933       (goto-char (point-min))
 934       (while (not (eobp))
 935         (skip-chars-forward " \t\n")
 936         (setq save-pos (point))
 937         (skip-chars-forward "^ \t\n")
 938         (downcase-region save-pos (point))
 939         (setq type (buffer-substring save-pos (point)))
 940         (while (not (eolp))
 941           (skip-chars-forward " \t")
 942           (setq save-pos (point))
 943           (skip-chars-forward "^ \t\n")
 944           (setq extns (cons (buffer-substring save-pos (point)) extns)))
 945         (while extns
 946           (setq mailcap-mime-extensions
 947                 (cons
 948                  (cons (if (= (string-to-char (car extns)) ?.)
 949                            (car extns)
 950                          (concat "." (car extns))) type)
 951                  mailcap-mime-extensions)
 952                 extns (cdr extns)))))))
 953
 954 (defun mailcap-extension-to-mime (extn)
 955   "Return the MIME content type of the file extensions EXTN."
 956   (mailcap-parse-mimetypes)
 957   (if (and (stringp extn)
 958            (not (eq (string-to-char extn) ?.)))
 959       (setq extn (concat "." extn)))
 960   (cdr (assoc (downcase extn) mailcap-mime-extensions)))
 961
 962 ;; Unused?
 963 (defalias 'mailcap-command-p 'executable-find)
 964
 965 (defun mailcap-mime-types ()
 966   "Return a list of MIME media types."
 967   (mailcap-parse-mimetypes)
 968   (mm-delete-duplicates
 969    (nconc
 970     (mapcar 'cdr mailcap-mime-extensions)
 971     (apply
 972      'nconc
 973      (mapcar
 974       (lambda (l)
 975         (delq nil
 976               (mapcar
 977                (lambda (m)
 978                  (let ((type (cdr (assq 'type (cdr m)))))
 979                    (if (equal (cadr (split-string type "/"))
 980                               "*")
 981                        nil
 982                      type)))
 983                (cdr l))))
 984       mailcap-mime-data)))))
 985
 986 (provide 'mailcap)
 987
 988 ;;; arch-tag: 1fd4f9c9-c305-4d2e-9747-3a4d45baa0bd
 989 ;;; mailcap.el ends here