lisp/gnus/mm-url.el

   1 ;;; mm-url.el --- a wrapper of url functions/commands for Gnus
   2
   3 ;; Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
   4 ;;   Free Software Foundation, Inc.
   5
   6 ;; Author: Shenghuo Zhu <zsh@cs.rochester.edu>
   7
   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 ;; Some codes are stolen from w3 and url packages. Some are moved from
  26 ;; nnweb.
  27
  28 ;; TODO: Support POST, cookie.
  29
  30 ;;; Code:
  31
  32 (eval-when-compile (require 'cl))
  33
  34 (require 'mm-util)
  35 (require 'gnus)
  36
  37 (defvar url-current-object)
  38 (defvar url-package-name)
  39 (defvar url-package-version)
  40
  41 (defgroup mm-url nil
  42   "A wrapper of url package and external url command for Gnus."
  43   :group 'gnus)
  44
  45 (defcustom mm-url-use-external (not
  46                                 (condition-case nil
  47                                     (require 'url)
  48                                   (error nil)))
  49   "*If non-nil, use external grab program `mm-url-program'."
  50   :version "22.1"
  51   :type 'boolean
  52   :group 'mm-url)
  53
  54 (defvar mm-url-predefined-programs
  55   '((wget "wget" "--user-agent=mm-url" "-q" "-O" "-")
  56     (w3m  "w3m" "-dump_source")
  57     (lynx "lynx" "-source")
  58     (curl "curl" "--silent" "--user-agent" "mm-url" "--location")))
  59
  60 (defcustom mm-url-program
  61   (cond
  62    ((executable-find "wget") 'wget)
  63    ((executable-find "w3m") 'w3m)
  64    ((executable-find "lynx") 'lynx)
  65    ((executable-find "curl") 'curl)
  66    (t "GET"))
  67   "The url grab program.
  68 Likely values are `wget', `w3m', `lynx' and `curl'."
  69   :version "22.1"
  70   :type '(choice
  71           (symbol :tag "wget" wget)
  72           (symbol :tag "w3m" w3m)
  73           (symbol :tag "lynx" lynx)
  74           (symbol :tag "curl" curl)
  75           (string :tag "other"))
  76   :group 'mm-url)
  77
  78 (defcustom mm-url-arguments nil
  79   "The arguments for `mm-url-program'."
  80   :version "22.1"
  81   :type '(repeat string)
  82   :group 'mm-url)
  83
  84 \f
  85 ;;; Internal variables
  86
  87 (defvar mm-url-package-name
  88   (gnus-replace-in-string
  89    (gnus-replace-in-string gnus-version " v.*$" "")
  90    " " "-"))
  91
  92 (defvar mm-url-package-version gnus-version-number)
  93
  94 ;; Stolen from w3.
  95 (defvar mm-url-html-entities
  96   '(
  97     ;;(excl        .  33)
  98     (quot        .  34)
  99     ;;(num         .  35)
 100     ;;(dollar      .  36)
 101     ;;(percent     .  37)
 102     (amp         .  38)
 103     (rsquo       .  39)                 ; should be U+8217
 104     ;;(apos        .  39)
 105     ;;(lpar        .  40)
 106     ;;(rpar        .  41)
 107     ;;(ast         .  42)
 108     ;;(plus        .  43)
 109     ;;(comma       .  44)
 110     ;;(period      .  46)
 111     ;;(colon       .  58)
 112     ;;(semi        .  59)
 113     (lt          .  60)
 114     ;;(equals      .  61)
 115     (gt          .  62)
 116     ;;(quest       .  63)
 117     ;;(commat      .  64)
 118     ;;(lsqb        .  91)
 119     ;;(rsqb        .  93)
 120     (uarr        .  94)                 ; should be U+8593
 121     ;;(lowbar      .  95)
 122     (lsquo       .  96)                 ; should be U+8216
 123     (lcub        . 123)
 124     ;;(verbar      . 124)
 125     (rcub        . 125)
 126     (tilde       . 126)
 127     (nbsp        . 160)
 128     (iexcl       . 161)
 129     (cent        . 162)
 130     (pound       . 163)
 131     (curren      . 164)
 132     (yen         . 165)
 133     (brvbar      . 166)
 134     (sect        . 167)
 135     (uml         . 168)
 136     (copy        . 169)
 137     (ordf        . 170)
 138     (laquo       . 171)
 139     (not         . 172)
 140     (shy         . 173)
 141     (reg         . 174)
 142     (macr        . 175)
 143     (deg         . 176)
 144     (plusmn      . 177)
 145     (sup2        . 178)
 146     (sup3        . 179)
 147     (acute       . 180)
 148     (micro       . 181)
 149     (para        . 182)
 150     (middot      . 183)
 151     (cedil       . 184)
 152     (sup1        . 185)
 153     (ordm        . 186)
 154     (raquo       . 187)
 155     (frac14      . 188)
 156     (frac12      . 189)
 157     (frac34      . 190)
 158     (iquest      . 191)
 159     (Agrave      . 192)
 160     (Aacute      . 193)
 161     (Acirc       . 194)
 162     (Atilde      . 195)
 163     (Auml        . 196)
 164     (Aring       . 197)
 165     (AElig       . 198)
 166     (Ccedil      . 199)
 167     (Egrave      . 200)
 168     (Eacute      . 201)
 169     (Ecirc       . 202)
 170     (Euml        . 203)
 171     (Igrave      . 204)
 172     (Iacute      . 205)
 173     (Icirc       . 206)
 174     (Iuml        . 207)
 175     (ETH         . 208)
 176     (Ntilde      . 209)
 177     (Ograve      . 210)
 178     (Oacute      . 211)
 179     (Ocirc       . 212)
 180     (Otilde      . 213)
 181     (Ouml        . 214)
 182     (times       . 215)
 183     (Oslash      . 216)
 184     (Ugrave      . 217)
 185     (Uacute      . 218)
 186     (Ucirc       . 219)
 187     (Uuml        . 220)
 188     (Yacute      . 221)
 189     (THORN       . 222)
 190     (szlig       . 223)
 191     (agrave      . 224)
 192     (aacute      . 225)
 193     (acirc       . 226)
 194     (atilde      . 227)
 195     (auml        . 228)
 196     (aring       . 229)
 197     (aelig       . 230)
 198     (ccedil      . 231)
 199     (egrave      . 232)
 200     (eacute      . 233)
 201     (ecirc       . 234)
 202     (euml        . 235)
 203     (igrave      . 236)
 204     (iacute      . 237)
 205     (icirc       . 238)
 206     (iuml        . 239)
 207     (eth         . 240)
 208     (ntilde      . 241)
 209     (ograve      . 242)
 210     (oacute      . 243)
 211     (ocirc       . 244)
 212     (otilde      . 245)
 213     (ouml        . 246)
 214     (divide      . 247)
 215     (oslash      . 248)
 216     (ugrave      . 249)
 217     (uacute      . 250)
 218     (ucirc       . 251)
 219     (uuml        . 252)
 220     (yacute      . 253)
 221     (thorn       . 254)
 222     (yuml        . 255)
 223
 224     ;; Special handling of these
 225     (frac56      . "5/6")
 226     (frac16      . "1/6")
 227     (frac45      . "4/5")
 228     (frac35      . "3/5")
 229     (frac25      . "2/5")
 230     (frac15      . "1/5")
 231     (frac23      . "2/3")
 232     (frac13      . "1/3")
 233     (frac78      . "7/8")
 234     (frac58      . "5/8")
 235     (frac38      . "3/8")
 236     (frac18      . "1/8")
 237
 238     ;; The following 5 entities are not mentioned in the HTML 2.0
 239     ;; standard, nor in any other HTML proposed standard of which I
 240     ;; am aware.  I am not even sure they are ISO entity names.  ***
 241     ;; Hence, some arrangement should be made to give a bad HTML
 242     ;; message when they are seen.
 243     (ndash       .  45)
 244     (mdash       .  45)
 245     (emsp        .  32)
 246     (ensp        .  32)
 247     (sim         . 126)
 248     (le          . "<=")
 249     (agr         . "alpha")
 250     (rdquo       . "''")
 251     (ldquo       . "``")
 252     (trade       . "(TM)")
 253     ;; To be done
 254     ;; (shy      . ????) ; soft hyphen
 255     )
 256   "*An assoc list of entity names and how to actually display them.")
 257
 258 (defconst mm-url-unreserved-chars
 259   '(
 260     ?a ?b ?c ?d ?e ?f ?g ?h ?i ?j ?k ?l ?m ?n ?o ?p ?q ?r ?s ?t ?u ?v ?w ?x ?y ?z
 261     ?A ?B ?C ?D ?E ?F ?G ?H ?I ?J ?K ?L ?M ?N ?O ?P ?Q ?R ?S ?T ?U ?V ?W ?X ?Y ?Z
 262     ?0 ?1 ?2 ?3 ?4 ?5 ?6 ?7 ?8 ?9
 263     ?- ?_ ?. ?! ?~ ?* ?' ?\( ?\))
 264   "A list of characters that are _NOT_ reserved in the URL spec.
 265 This is taken from RFC 2396.")
 266
 267 (defun mm-url-load-url ()
 268   "Load `url-insert-file-contents'."
 269   (unless (condition-case ()
 270               (progn
 271                 (require 'url-handlers)
 272                 (require 'url-parse)
 273                 (require 'url-vars))
 274             (error nil))
 275     ;; w3-4.0pre0.46 or earlier version.
 276     (require 'w3-vars)
 277     (require 'url)))
 278
 279 ;;;###autoload
 280 (defun mm-url-insert-file-contents (url)
 281   "Insert file contents of URL.
 282 If `mm-url-use-external' is non-nil, use `mm-url-program'."
 283   (if mm-url-use-external
 284       (progn
 285         (if (string-match "^file:/+" url)
 286             (insert-file-contents (substring url (1- (match-end 0))))
 287           (mm-url-insert-file-contents-external url))
 288         (goto-char (point-min))
 289         (if (fboundp 'url-generic-parse-url)
 290             (setq url-current-object
 291                   (url-generic-parse-url url)))
 292         (list url (buffer-size)))
 293     (mm-url-load-url)
 294     (let ((name buffer-file-name)
 295           (url-request-extra-headers
 296            ;; ISTM setting a Connection header was a workaround for
 297            ;; older versions of url included with w3, but it does more
 298            ;; harm than good with the one shipped with Emacs. --ansel
 299            (if (not (and (boundp 'url-version)
 300                          (equal url-version "Emacs")))
 301                (list (cons "Connection" "Close"))))
 302           (url-package-name (or mm-url-package-name
 303                                 url-package-name))
 304           (url-package-version (or mm-url-package-version
 305                                    url-package-version))
 306           result)
 307       (setq result (url-insert-file-contents url))
 308       (save-excursion
 309         (goto-char (point-min))
 310         (while (re-search-forward "\r 1000\r ?" nil t)
 311           (replace-match "")))
 312       (setq buffer-file-name name)
 313       (if (and (fboundp 'url-generic-parse-url)
 314                (listp result))
 315           (setq url-current-object (url-generic-parse-url
 316                                     (car result))))
 317       result)))
 318
 319 ;;;###autoload
 320 (defun mm-url-insert-file-contents-external (url)
 321   "Insert file contents of URL using `mm-url-program'."
 322   (let (program args)
 323     (if (symbolp mm-url-program)
 324         (let ((item (cdr (assq mm-url-program mm-url-predefined-programs))))
 325           (setq program (car item)
 326                 args (append (cdr item) (list url))))
 327       (setq program mm-url-program
 328             args (append mm-url-arguments (list url))))
 329     (unless (eq 0 (apply 'call-process program nil t nil args))
 330       (error "Couldn't fetch %s" url))))
 331
 332 (defvar mm-url-timeout 30
 333   "The number of seconds before timing out an URL fetch.")
 334
 335 (defvar mm-url-retries 10
 336   "The number of retries after timing out when fetching an URL.")
 337
 338 (defun mm-url-insert (url &optional follow-refresh)
 339   "Insert the contents from an URL in the current buffer.
 340 If FOLLOW-REFRESH is non-nil, redirect refresh url in META."
 341   (let ((times mm-url-retries)
 342         (done nil)
 343         (first t)
 344         result)
 345     (while (and (not (zerop (decf times)))
 346                 (not done))
 347       (with-timeout (mm-url-timeout)
 348         (unless first
 349           (message "Trying again (%s)..." (- mm-url-retries times)))
 350         (setq first nil)
 351         (if follow-refresh
 352             (save-restriction
 353               (narrow-to-region (point) (point))
 354               (mm-url-insert-file-contents url)
 355               (goto-char (point-min))
 356               (when (re-search-forward
 357                      "<meta[ \t\r\n]*http-equiv=\"Refresh\"[^>]*URL=\\([^\"]+\\)\"" nil t)
 358                 (let ((url (match-string 1)))
 359                   (delete-region (point-min) (point-max))
 360                   (setq result (mm-url-insert url t)))))
 361           (setq result (mm-url-insert-file-contents url)))
 362         (setq done t)))
 363     result))
 364
 365 (defun mm-url-decode-entities ()
 366   "Decode all HTML entities."
 367   (goto-char (point-min))
 368   (while (re-search-forward "&\\(#[0-9]+\\|[a-z]+[0-9]*\\);" nil t)
 369     (let ((elem (if (eq (aref (match-string 1) 0) ?\#)
 370                         (let ((c (mm-ucs-to-char
 371                                   (string-to-number
 372                                    (substring (match-string 1) 1)))))
 373                           (if (mm-char-or-char-int-p c) c ?#))
 374                       (or (cdr (assq (intern (match-string 1))
 375                                      mm-url-html-entities))
 376                           ?#))))
 377       (unless (stringp elem)
 378         (setq elem (char-to-string elem)))
 379       (replace-match elem t t))))
 380
 381 (defun mm-url-decode-entities-nbsp ()
 382   "Decode all HTML entities and &nbsp; to a space."
 383   (let ((mm-url-html-entities (cons '(nbsp . 32) mm-url-html-entities)))
 384     (mm-url-decode-entities)))
 385
 386 (defun mm-url-decode-entities-string (string)
 387   (with-temp-buffer
 388     (insert string)
 389     (mm-url-decode-entities)
 390     (buffer-string)))
 391
 392 (defun mm-url-form-encode-xwfu (chunk)
 393   "Escape characters in a string for application/x-www-form-urlencoded.
 394 Blasphemous crap because someone didn't think %20 was good enough for encoding
 395 spaces.  Die Die Die."
 396   ;; This will get rid of the 'attributes' specified by the file type,
 397   ;; which are useless for an application/x-www-form-urlencoded form.
 398   (if (consp chunk)
 399       (setq chunk (cdr chunk)))
 400
 401   (mapconcat
 402    (lambda (char)
 403      (cond
 404       ((= char ?  ) "+")
 405       ((memq char mm-url-unreserved-chars) (char-to-string char))
 406       (t (upcase (format "%%%02x" char)))))
 407    ;; Fixme: Should this actually be accepting multibyte?  Is there a
 408    ;; better way in XEmacs?
 409    (if (featurep 'mule)
 410        (encode-coding-string chunk
 411                              (if (fboundp 'find-coding-systems-string)
 412                                  (car (find-coding-systems-string chunk))
 413                                  buffer-file-coding-system))
 414      chunk)
 415    ""))
 416
 417 (defun mm-url-encode-www-form-urlencoded (pairs)
 418   "Return PAIRS encoded for forms."
 419   (mapconcat
 420    (lambda (data)
 421      (concat (mm-url-form-encode-xwfu (car data)) "="
 422              (mm-url-form-encode-xwfu (cdr data))))
 423    pairs "&"))
 424
 425 (defun mm-url-fetch-form (url pairs)
 426   "Fetch a form from URL with PAIRS as the data using the POST method."
 427   (mm-url-load-url)
 428   (let ((url-request-data (mm-url-encode-www-form-urlencoded pairs))
 429         (url-request-method "POST")
 430         (url-request-extra-headers
 431          '(("Content-type" . "application/x-www-form-urlencoded"))))
 432     (url-insert-file-contents url)
 433     (setq buffer-file-name nil))
 434   t)
 435
 436 (defun mm-url-fetch-simple (url content)
 437   (mm-url-load-url)
 438   (let ((url-request-data content)
 439         (url-request-method "POST")
 440         (url-request-extra-headers
 441          '(("Content-type" . "application/x-www-form-urlencoded"))))
 442     (url-insert-file-contents url)
 443     (setq buffer-file-name nil))
 444   t)
 445
 446 (defun mm-url-remove-markup ()
 447   "Remove all HTML markup, leaving just plain text."
 448   (goto-char (point-min))
 449   (while (search-forward "<!--" nil t)
 450     (delete-region (match-beginning 0)
 451                    (or (search-forward "-->" nil t)
 452                        (point-max))))
 453   (goto-char (point-min))
 454   (while (re-search-forward "<[^>]+>" nil t)
 455     (replace-match "" t t)))
 456
 457 (provide 'mm-url)
 458
 459 ;; arch-tag: 0594f9b3-417c-48b0-adc2-5082e1e7917f
 460 ;;; mm-url.el ends here