mirror of
git://git.sv.gnu.org/emacs.git
synced 2025-12-14 10:00:25 -08:00
bc511a64f6
Most of this change is to boilerplate commentary such as license URLs. This change was prompted by ftp://ftp.gnu.org's going-away party, planned for November. Change these FTP URLs to https://ftp.gnu.org instead. Make similar changes for URLs to other organizations moving away from FTP. Also, change HTTP to HTTPS for URLs to gnu.org and fsf.org when this works, as this will further help defend against man-in-the-middle attacks (for this part I omitted the MS-DOS and MS-Windows sources and the test tarballs to keep the workload down). HTTPS is not fully working to lists.gnu.org so I left those URLs alone for now.
509 lines
18 KiB
EmacsLisp
509 lines
18 KiB
EmacsLisp
;;; gnus-html.el --- Render HTML in a buffer.
|
|
|
|
;; Copyright (C) 2010-2017 Free Software Foundation, Inc.
|
|
|
|
;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
|
|
;; Keywords: html, web
|
|
|
|
;; This file is part of GNU Emacs.
|
|
|
|
;; GNU Emacs is free software: you can redistribute it and/or modify
|
|
;; it under the terms of the GNU General Public License as published by
|
|
;; the Free Software Foundation, either version 3 of the License, or
|
|
;; (at your option) any later version.
|
|
|
|
;; GNU Emacs is distributed in the hope that it will be useful,
|
|
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
;; GNU General Public License for more details.
|
|
|
|
;; You should have received a copy of the GNU General Public License
|
|
;; along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>.
|
|
|
|
;;; Commentary:
|
|
|
|
;; The idea is to provide a simple, fast and pretty minimal way to
|
|
;; render HTML (including links and images) in a buffer, based on an
|
|
;; external HTML renderer (i.e., w3m).
|
|
|
|
;;; Code:
|
|
|
|
(eval-when-compile (require 'cl))
|
|
|
|
(require 'gnus-art)
|
|
(eval-when-compile (require 'mm-decode))
|
|
|
|
(require 'mm-url)
|
|
(require 'url)
|
|
(require 'url-cache)
|
|
(require 'xml)
|
|
(require 'browse-url)
|
|
(require 'mm-util)
|
|
(require 'help-fns)
|
|
(require 'url-queue)
|
|
|
|
(defcustom gnus-html-image-cache-ttl (days-to-time 7)
|
|
"Time used to determine if we should use images from the cache."
|
|
:version "24.1"
|
|
:group 'gnus-art
|
|
;; FIXME hardly the friendliest type. The allowed value is actually
|
|
;; any time value, but we are assuming no-one cares about USEC and
|
|
;; PSEC here. It would be better to eg make it a number of minutes.
|
|
:type '(list integer integer))
|
|
|
|
(defcustom gnus-html-image-automatic-caching t
|
|
"Whether automatically cache retrieve images."
|
|
:version "24.1"
|
|
:group 'gnus-art
|
|
:type 'boolean)
|
|
|
|
(defcustom gnus-html-frame-width 70
|
|
"What width to use when rendering HTML."
|
|
:version "24.1"
|
|
:group 'gnus-art
|
|
:type 'integer)
|
|
|
|
(defcustom gnus-max-image-proportion 0.9
|
|
"How big pictures displayed are in relation to the window they're in.
|
|
A value of 0.7 means that they are allowed to take up 70% of the
|
|
width and height of the window. If they are larger than this,
|
|
and Emacs supports it, then the images will be rescaled down to
|
|
fit these criteria."
|
|
:version "24.1"
|
|
:group 'gnus-art
|
|
:type 'float)
|
|
|
|
(defvar gnus-html-image-map
|
|
(let ((map (make-sparse-keymap)))
|
|
(define-key map "u" 'gnus-article-copy-string)
|
|
(define-key map "i" 'gnus-html-insert-image)
|
|
(define-key map "v" 'gnus-html-browse-url)
|
|
map))
|
|
|
|
(defvar gnus-html-displayed-image-map
|
|
(let ((map (make-sparse-keymap)))
|
|
(define-key map "a" 'gnus-html-show-alt-text)
|
|
(define-key map "i" 'gnus-html-browse-image)
|
|
(define-key map "\r" 'gnus-html-browse-url)
|
|
(define-key map "u" 'gnus-article-copy-string)
|
|
(define-key map [tab] 'widget-forward)
|
|
map))
|
|
|
|
(defun gnus-html-encode-url (url)
|
|
"Encode URL."
|
|
(browse-url-url-encode-chars url "[)$ ]"))
|
|
|
|
(defun gnus-html-cache-expired (url ttl)
|
|
"Check if URL is cached for more than TTL."
|
|
(cond (url-standalone-mode
|
|
(not (file-exists-p (url-cache-create-filename url))))
|
|
(t (let ((cache-time (url-is-cached url)))
|
|
(if cache-time
|
|
(time-less-p
|
|
(time-add
|
|
cache-time
|
|
ttl)
|
|
(current-time))
|
|
t)))))
|
|
|
|
;;;###autoload
|
|
(defun gnus-article-html (&optional handle)
|
|
(let ((article-buffer (current-buffer)))
|
|
(unless handle
|
|
(setq handle (mm-dissect-buffer t)))
|
|
(save-restriction
|
|
(narrow-to-region (point) (point))
|
|
(save-excursion
|
|
(mm-with-part handle
|
|
(let* ((coding-system-for-read 'utf-8)
|
|
(coding-system-for-write 'utf-8)
|
|
(default-process-coding-system
|
|
(cons coding-system-for-read coding-system-for-write))
|
|
(charset (mail-content-type-get (mm-handle-type handle)
|
|
'charset)))
|
|
(when (and charset
|
|
(setq charset (mm-charset-to-coding-system
|
|
charset nil t))
|
|
(not (eq charset 'ascii)))
|
|
(insert (prog1
|
|
(decode-coding-string (buffer-string) charset)
|
|
(erase-buffer)
|
|
(mm-enable-multibyte))))
|
|
(call-process-region (point-min) (point-max)
|
|
"w3m"
|
|
nil article-buffer nil
|
|
"-halfdump"
|
|
"-no-cookie"
|
|
"-I" "UTF-8"
|
|
"-O" "UTF-8"
|
|
"-o" "ext_halfdump=1"
|
|
"-o" "display_ins_del=2"
|
|
"-o" "pre_conv=1"
|
|
"-t" (format "%s" tab-width)
|
|
"-cols" (format "%s" gnus-html-frame-width)
|
|
"-o" "display_image=on"
|
|
"-T" "text/html"))))
|
|
(gnus-html-wash-tags))))
|
|
|
|
(defvar gnus-article-mouse-face)
|
|
|
|
(defun gnus-html-pre-wash ()
|
|
(goto-char (point-min))
|
|
(while (re-search-forward " *<pre_int> *</pre_int> *\n" nil t)
|
|
(replace-match "" t t))
|
|
(goto-char (point-min))
|
|
(while (re-search-forward "<a name[^\n>]+>" nil t)
|
|
(replace-match "" t t)))
|
|
|
|
(defun gnus-html-wash-images ()
|
|
"Run through current buffer and replace img tags by images."
|
|
(let (tag parameters string start end images url alt-text
|
|
inhibit-images blocked-images)
|
|
(if (buffer-live-p gnus-summary-buffer)
|
|
(with-current-buffer gnus-summary-buffer
|
|
(setq inhibit-images gnus-inhibit-images
|
|
blocked-images (gnus-blocked-images)))
|
|
(setq inhibit-images gnus-inhibit-images
|
|
blocked-images (gnus-blocked-images)))
|
|
(goto-char (point-min))
|
|
;; Search for all the images first.
|
|
(while (re-search-forward "<img_alt \\([^>]*\\)>" nil t)
|
|
(setq parameters (match-string 1)
|
|
start (match-beginning 0))
|
|
(delete-region start (point))
|
|
(when (search-forward "</img_alt>" (line-end-position) t)
|
|
(delete-region (match-beginning 0) (match-end 0)))
|
|
(setq end (point))
|
|
(when (string-match "src=\"\\([^\"]+\\)" parameters)
|
|
(gnus-message 8 "gnus-html-wash-tags: fetching image URL %s" url)
|
|
(setq url (gnus-html-encode-url (match-string 1 parameters))
|
|
alt-text (when (string-match "\\(alt\\|title\\)=\"\\([^\"]+\\)"
|
|
parameters)
|
|
(xml-substitute-special (match-string 2 parameters))))
|
|
(add-text-properties
|
|
start end
|
|
(list 'image-url url
|
|
'image-displayer `(lambda (url start end)
|
|
(gnus-html-display-image url start end
|
|
,alt-text))
|
|
'gnus-image (list url start end alt-text)))
|
|
(widget-convert-button
|
|
'url-link start (point)
|
|
:help-echo alt-text
|
|
:keymap gnus-html-image-map
|
|
url)
|
|
(if (string-match "\\`cid:" url)
|
|
;; URLs with cid: have their content stashed in other
|
|
;; parts of the MIME structure, so just insert them
|
|
;; immediately.
|
|
(let* ((handle (mm-get-content-id (substring url (match-end 0))))
|
|
(image (when (and handle
|
|
(not inhibit-images))
|
|
(gnus-create-image
|
|
(mm-with-part handle (buffer-string))
|
|
nil t))))
|
|
(if image
|
|
(gnus-add-image
|
|
'cid
|
|
(gnus-put-image
|
|
(gnus-rescale-image
|
|
image (gnus-html-maximum-image-size))
|
|
(gnus-string-or (prog1
|
|
(buffer-substring start end)
|
|
(delete-region start end))
|
|
"*")
|
|
'cid))
|
|
(widget-convert-button
|
|
'link start end
|
|
:action 'gnus-html-insert-image
|
|
:help-echo url
|
|
:keymap gnus-html-image-map
|
|
:button-keymap gnus-html-image-map)))
|
|
;; Normal, external URL.
|
|
(if (or inhibit-images
|
|
(gnus-html-image-url-blocked-p url blocked-images))
|
|
(widget-convert-button
|
|
'link start end
|
|
:action 'gnus-html-insert-image
|
|
:help-echo url
|
|
:keymap gnus-html-image-map
|
|
:button-keymap gnus-html-image-map)
|
|
;; Non-blocked url
|
|
(let ((width
|
|
(when (string-match "width=\"?\\([0-9]+\\)" parameters)
|
|
(string-to-number (match-string 1 parameters))))
|
|
(height
|
|
(when (string-match "height=\"?\\([0-9]+\\)" parameters)
|
|
(string-to-number (match-string 1 parameters)))))
|
|
;; Don't fetch images that are really small. They're
|
|
;; probably tracking pictures.
|
|
(when (and (or (null height)
|
|
(> height 4))
|
|
(or (null width)
|
|
(> width 4)))
|
|
(gnus-html-display-image url start end alt-text)))))))))
|
|
|
|
(defun gnus-html-display-image (url start end &optional alt-text)
|
|
"Display image at URL on text from START to END.
|
|
Use ALT-TEXT for the image string."
|
|
(or alt-text (setq alt-text "*"))
|
|
(if (string-match "\\`cid:" url)
|
|
(let ((handle (mm-get-content-id (substring url (match-end 0)))))
|
|
(when handle
|
|
(gnus-html-put-image (mm-with-part handle (buffer-string))
|
|
url alt-text)))
|
|
(if (gnus-html-cache-expired url gnus-html-image-cache-ttl)
|
|
;; We don't have it, so schedule it for fetching
|
|
;; asynchronously.
|
|
(gnus-html-schedule-image-fetching
|
|
(current-buffer)
|
|
(list url alt-text))
|
|
;; It's already cached, so just insert it.
|
|
(gnus-html-put-image (gnus-html-get-image-data url) url alt-text))))
|
|
|
|
(defun gnus-html-wash-tags ()
|
|
(let (tag parameters string start end images url)
|
|
(gnus-html-pre-wash)
|
|
(gnus-html-wash-images)
|
|
|
|
(goto-char (point-min))
|
|
;; Then do the other tags.
|
|
(while (re-search-forward "<\\([^ />]+\\)\\([^>]*\\)>" nil t)
|
|
(setq tag (match-string 1)
|
|
parameters (match-string 2)
|
|
start (match-beginning 0))
|
|
(when (> (length parameters) 0)
|
|
(set-text-properties 0 (1- (length parameters)) nil parameters))
|
|
(delete-region start (point))
|
|
(when (search-forward (concat "</" tag ">") nil t)
|
|
(delete-region (match-beginning 0) (match-end 0)))
|
|
(setq end (point))
|
|
(cond
|
|
;; Fetch and insert a picture.
|
|
((equal tag "img_alt"))
|
|
;; Add a link.
|
|
((or (equal tag "a")
|
|
(equal tag "A"))
|
|
(when (string-match "href=\"\\([^\"]+\\)" parameters)
|
|
(setq url (match-string 1 parameters))
|
|
(gnus-message 8 "gnus-html-wash-tags: fetching link URL %s" url)
|
|
(gnus-article-add-button start end
|
|
'browse-url (mm-url-decode-entities-string url)
|
|
url)
|
|
(let ((overlay (make-overlay start end)))
|
|
(overlay-put overlay 'evaporate t)
|
|
(overlay-put overlay 'gnus-button-url url)
|
|
(put-text-property start end 'gnus-string url)
|
|
(when gnus-article-mouse-face
|
|
(overlay-put overlay 'mouse-face gnus-article-mouse-face)))))
|
|
;; The upper-case IMG_ALT is apparently just an artifact that
|
|
;; should be deleted.
|
|
((equal tag "IMG_ALT")
|
|
(delete-region start end))
|
|
;; w3m does not normalize the case
|
|
((or (equal tag "b")
|
|
(equal tag "B"))
|
|
(overlay-put (make-overlay start end) 'face 'gnus-emphasis-bold))
|
|
((or (equal tag "u")
|
|
(equal tag "U"))
|
|
(overlay-put (make-overlay start end) 'face 'gnus-emphasis-underline))
|
|
((or (equal tag "i")
|
|
(equal tag "I"))
|
|
(overlay-put (make-overlay start end) 'face 'gnus-emphasis-italic))
|
|
((or (equal tag "s")
|
|
(equal tag "S"))
|
|
(overlay-put (make-overlay start end) 'face 'gnus-emphasis-strikethru))
|
|
((or (equal tag "ins")
|
|
(equal tag "INS"))
|
|
(overlay-put (make-overlay start end) 'face 'gnus-emphasis-underline))
|
|
;; Handle different UL types
|
|
((equal tag "_SYMBOL")
|
|
(when (string-match "TYPE=\\(.+\\)" parameters)
|
|
(let ((type (string-to-number (match-string 1 parameters))))
|
|
(delete-region start end)
|
|
(cond ((= type 33) (insert " "))
|
|
((= type 34) (insert " "))
|
|
((= type 35) (insert " "))
|
|
((= type 36) (insert " "))
|
|
((= type 37) (insert " "))
|
|
((= type 38) (insert " "))
|
|
((= type 39) (insert " "))
|
|
((= type 40) (insert " "))
|
|
((= type 42) (insert " "))
|
|
((= type 43) (insert " "))
|
|
(t (insert " "))))))
|
|
;; Whatever. Just ignore the tag.
|
|
(t
|
|
))
|
|
(goto-char start))
|
|
(goto-char (point-min))
|
|
;; The output from -halfdump isn't totally regular, so strip
|
|
;; off any </pre_int>s that were left over.
|
|
(while (re-search-forward "</pre_int>\\|</internal>" nil t)
|
|
(replace-match "" t t))
|
|
(mm-url-decode-entities)))
|
|
|
|
(defun gnus-html-insert-image (&rest args)
|
|
"Fetch and insert the image under point."
|
|
(interactive)
|
|
(apply 'gnus-html-display-image (get-text-property (point) 'gnus-image)))
|
|
|
|
(defun gnus-html-show-alt-text ()
|
|
"Show the ALT text of the image under point."
|
|
(interactive)
|
|
(message "%s" (get-text-property (point) 'gnus-alt-text)))
|
|
|
|
(defun gnus-html-browse-image ()
|
|
"Browse the image under point."
|
|
(interactive)
|
|
(browse-url (get-text-property (point) 'image-url)))
|
|
|
|
(defun gnus-html-browse-url ()
|
|
"Browse the image under point."
|
|
(interactive)
|
|
(let ((url (get-text-property (point) 'gnus-string)))
|
|
(cond
|
|
((not url)
|
|
(message "No link under point"))
|
|
((string-match "^mailto:" url)
|
|
(gnus-url-mailto url))
|
|
(t
|
|
(browse-url url)))))
|
|
|
|
(defun gnus-html-schedule-image-fetching (buffer image)
|
|
"Retrieve IMAGE, and place it into BUFFER on arrival."
|
|
(gnus-message 8 "gnus-html-schedule-image-fetching: buffer %s, image %s"
|
|
buffer image)
|
|
(url-queue-retrieve (car image)
|
|
'gnus-html-image-fetched
|
|
(list buffer image) t t))
|
|
|
|
(defun gnus-html-image-fetched (status buffer image)
|
|
"Callback function called when image has been fetched."
|
|
(unless (plist-get status :error)
|
|
(when (and (or (search-forward "\n\n" nil t)
|
|
(search-forward "\r\n\r\n" nil t))
|
|
(not (eobp)))
|
|
(when gnus-html-image-automatic-caching
|
|
(url-store-in-cache (current-buffer)))
|
|
(when (buffer-live-p buffer)
|
|
(let ((data (buffer-substring (point) (point-max))))
|
|
(with-current-buffer buffer
|
|
(let ((inhibit-read-only t))
|
|
(gnus-html-put-image data (car image) (cadr image))))))))
|
|
(kill-buffer (current-buffer)))
|
|
|
|
(defun gnus-html-get-image-data (url)
|
|
"Get image data for URL.
|
|
Return a string with image data."
|
|
(with-temp-buffer
|
|
(mm-disable-multibyte)
|
|
(url-cache-extract (url-cache-create-filename url))
|
|
(when (or (search-forward "\n\n" nil t)
|
|
(search-forward "\r\n\r\n" nil t))
|
|
(buffer-substring (point) (point-max)))))
|
|
|
|
(defun gnus-html-maximum-image-size ()
|
|
"Return the maximum size of an image according to `gnus-max-image-proportion'."
|
|
(let ((edges (window-inside-pixel-edges
|
|
(get-buffer-window (current-buffer)))))
|
|
;; (width . height)
|
|
(cons
|
|
;; Aimed width
|
|
(truncate
|
|
(* gnus-max-image-proportion
|
|
(- (nth 2 edges) (nth 0 edges))))
|
|
;; Aimed height
|
|
(truncate (* gnus-max-image-proportion
|
|
(- (nth 3 edges) (nth 1 edges)))))))
|
|
|
|
;; Behind display-graphic-p test.
|
|
(declare-function image-size "image.c" (spec &optional pixels frame))
|
|
|
|
(defun gnus-html-put-image (data url &optional alt-text)
|
|
"Put an image with DATA from URL and optional ALT-TEXT."
|
|
(when (display-graphic-p)
|
|
(let* ((start (text-property-any (point-min) (point-max)
|
|
'image-url url))
|
|
(end (when start
|
|
(next-single-property-change start 'image-url))))
|
|
;; Image found?
|
|
(when start
|
|
(let* ((image
|
|
(ignore-errors
|
|
(gnus-create-image data nil t)))
|
|
(size (and image (image-size image t))))
|
|
(save-excursion
|
|
(goto-char start)
|
|
(let ((alt-text (or alt-text
|
|
(buffer-substring-no-properties start end)))
|
|
(inhibit-read-only t))
|
|
(if (and image
|
|
;; Kludge to avoid displaying 30x30 gif images, which
|
|
;; seems to be a signal of a broken image.
|
|
(not (and (listp image)
|
|
(eq (plist-get (cdr image) :type)
|
|
'gif)
|
|
(= (car size) 30)
|
|
(= (cdr size) 30))))
|
|
;; Good image, add it!
|
|
(let ((image (gnus-rescale-image image (gnus-html-maximum-image-size))))
|
|
(delete-region start end)
|
|
(gnus-put-image image alt-text 'external)
|
|
(widget-convert-button
|
|
'url-link start (point)
|
|
:help-echo alt-text
|
|
:keymap gnus-html-displayed-image-map
|
|
url)
|
|
(put-text-property start (point) 'gnus-alt-text alt-text)
|
|
(when url
|
|
(add-text-properties
|
|
start (point)
|
|
`(image-url
|
|
,url
|
|
image-displayer
|
|
(lambda (url start end)
|
|
(gnus-html-display-image url start end
|
|
,alt-text)))))
|
|
(gnus-add-image 'external image)
|
|
t)
|
|
;; Bad image, try to show something else
|
|
(when (fboundp 'find-image)
|
|
(delete-region start end)
|
|
(setq image (find-image
|
|
'((:type xpm :file "lock-broken.xpm"))))
|
|
(gnus-put-image image alt-text 'internal)
|
|
(gnus-add-image 'internal image))
|
|
nil))))))))
|
|
|
|
(defun gnus-html-image-url-blocked-p (url blocked-images)
|
|
"Find out if URL is blocked by BLOCKED-IMAGES."
|
|
(let ((ret (and blocked-images
|
|
(string-match blocked-images url))))
|
|
(if ret
|
|
(gnus-message 8 "gnus-html-image-url-blocked-p: %s blocked by regex %s"
|
|
url blocked-images)
|
|
(gnus-message 9 "gnus-html-image-url-blocked-p: %s passes regex %s"
|
|
url blocked-images))
|
|
ret))
|
|
|
|
;;;###autoload
|
|
(defun gnus-html-prefetch-images (summary)
|
|
(when (buffer-live-p summary)
|
|
(let (inhibit-images blocked-images)
|
|
(with-current-buffer summary
|
|
(setq inhibit-images gnus-inhibit-images
|
|
blocked-images (gnus-blocked-images)))
|
|
(save-match-data
|
|
(while (re-search-forward "<img[^>]+src=[\"']\\(http[^\"']+\\)" nil t)
|
|
(let ((url (gnus-html-encode-url
|
|
(mm-url-decode-entities-string (match-string 1)))))
|
|
(unless (or inhibit-images
|
|
(gnus-html-image-url-blocked-p url blocked-images))
|
|
(when (gnus-html-cache-expired url gnus-html-image-cache-ttl)
|
|
(gnus-html-schedule-image-fetching nil
|
|
(list url))))))))))
|
|
|
|
(provide 'gnus-html)
|
|
|
|
;;; gnus-html.el ends here
|