;;; shr.el --- Simple HTML Renderer -*- lexical-binding: t -*-
;; Copyright (C) 2010-2019 Free Software Foundation, Inc.
;; Author: Lars Magne Ingebrigtsen
;; Keywords: html
;; 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 .
;;; Commentary:
;; This package takes a HTML parse tree (as provided by
;; libxml-parse-html-region) and renders it in the current buffer. It
;; does not do CSS, JavaScript or anything advanced: It's geared
;; towards rendering typical short snippets of HTML, like what you'd
;; find in HTML email and the like.
;;; Code:
(require 'cl-lib)
(eval-when-compile (require 'url)) ;For url-filename's setf handler.
(require 'browse-url)
(eval-when-compile (require 'subr-x))
(require 'dom)
(require 'seq)
(require 'svg)
(require 'image)
(require 'puny)
(require 'url-cookie)
(require 'text-property-search)
(defgroup shr nil
"Simple HTML Renderer"
:version "25.1"
:group 'web)
(defcustom shr-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"
:type 'float)
(defcustom shr-blocked-images nil
"Images that have URLs matching this regexp will be blocked."
:version "24.1"
:type '(choice (const nil) regexp))
(defcustom shr-use-fonts t
"If non-nil, use proportional fonts for text."
:version "25.1"
:type 'boolean)
(defcustom shr-discard-aria-hidden nil
"If non-nil, don't render tags with `aria-hidden=\"true\"'.
This attribute is meant to tell screen readers to ignore a tag."
:version "27.1"
:type 'boolean)
(defcustom shr-use-colors t
"If non-nil, respect color specifications in the HTML."
:version "26.1"
:type 'boolean)
(defcustom shr-table-horizontal-line nil
"Character used to draw horizontal table lines.
If nil, don't draw horizontal table lines."
:type '(choice (const nil) character))
(defcustom shr-table-vertical-line ?\s
"Character used to draw vertical table lines."
:type 'character)
(defcustom shr-table-corner ?\s
"Character used to draw table corners."
:type 'character)
(defcustom shr-hr-line ?-
"Character used to draw hr lines."
:type 'character)
(defcustom shr-width nil
"Frame width to use for rendering.
May either be an integer specifying a fixed width in characters,
or nil, meaning that the full width of the window should be used.
If `shr-use-fonts' is set, the mean character width is used to
compute the pixel width, which is used instead."
:version "25.1"
:type '(choice (integer :tag "Fixed width in characters")
(const :tag "Use the width of the window" nil)))
(defcustom shr-bullet "* "
"Bullet used for unordered lists.
Alternative suggestions are:
- \" \"
- \" \""
:version "24.4"
:type 'string)
(defcustom shr-cookie-policy 'same-origin
"When to use cookies when fetching dependent data like images.
If t, always use cookies. If nil, never use cookies. If
`same-origin', use cookies if the dependent data comes from the
same domain as the main data."
:type '(choice (const :tag "Always use cookies" t)
(const :tag "Never use cookies" nil)
(const :tag "Use cookies for same domain" same-origin))
:version "27.1")
(define-obsolete-variable-alias 'shr-external-browser
'browse-url-secondary-browser-function "27.1")
(defcustom shr-image-animate t
"Non-nil means that images that can be animated will be."
:version "24.4"
:type 'boolean)
(defvar shr-content-function nil
"If bound, this should be a function that will return the content.
This is used for cid: URLs, and the function is called with the
cid: URL as the argument.")
(defvar shr-put-image-function 'shr-put-image
"Function called to put image and alt string.")
(defface shr-strike-through '((t :strike-through t))
"Face for elements."
:version "24.1")
(defface shr-link
'((t :inherit link))
"Face for link elements."
:version "24.1")
(defface shr-selected-link
'((t :inherit shr-link :background "red"))
"Temporary face for externally visited link elements.
When a link is visited with an external browser, the link
temporarily blinks with this face."
:version "27.1")
(defface shr-abbreviation
'((t :inherit underline :underline (:style wave)))
"Face for elements."
:version "27.1")
(defvar shr-inhibit-images nil
"If non-nil, inhibit loading images.")
(defvar shr-external-rendering-functions nil
"Alist of tag/function pairs used to alter how shr renders certain tags.
For instance, eww uses this to alter rendering of title, forms
and other things:
\((title . eww-tag-title)
(form . eww-tag-form)
...)")
;;; Internal variables.
(defvar shr-folding-mode nil)
(defvar shr-start nil)
(defvar shr-indentation 0)
(defvar shr-internal-width nil)
(defvar shr-list-mode nil)
(defvar shr-content-cache nil)
(defvar shr-kinsoku-shorten nil)
(defvar shr-table-depth 0)
(defvar shr-stylesheet nil)
(defvar shr-base nil)
(defvar shr-depth 0)
(defvar shr-warning nil)
(defvar shr-ignore-cache nil)
(defvar shr-target-id nil)
(defvar shr-table-separator-length 1)
(defvar shr-table-separator-pixel-width 0)
(defvar shr-table-id nil)
(defvar shr-current-font nil)
(defvar shr-internal-bullet nil)
(defvar shr-map
(let ((map (make-sparse-keymap)))
(define-key map "a" 'shr-show-alt-text)
(define-key map "i" 'shr-browse-image)
(define-key map "z" 'shr-zoom-image)
(define-key map [?\t] 'shr-next-link)
(define-key map [?\M-\t] 'shr-previous-link)
(define-key map [follow-link] 'mouse-face)
(define-key map [mouse-2] 'shr-browse-url)
(define-key map [C-down-mouse-1] 'shr-mouse-browse-url-new-window)
(define-key map "I" 'shr-insert-image)
(define-key map "w" 'shr-maybe-probe-and-copy-url)
(define-key map "u" 'shr-maybe-probe-and-copy-url)
(define-key map "v" 'shr-browse-url)
(define-key map "O" 'shr-save-contents)
(define-key map "\r" 'shr-browse-url)
map))
(defvar shr-image-map
(let ((map (copy-keymap shr-map)))
(when (boundp 'image-map)
(set-keymap-parent map image-map))
map))
;; Public functions and commands.
(declare-function libxml-parse-html-region "xml.c"
(start end &optional base-url discard-comments))
(defun shr-render-buffer (buffer)
"Display the HTML rendering of the current buffer."
(interactive (list (current-buffer)))
(or (fboundp 'libxml-parse-html-region)
(error "This function requires Emacs to be compiled with libxml2"))
(pop-to-buffer "*html*")
(erase-buffer)
(shr-insert-document
(with-current-buffer buffer
(libxml-parse-html-region (point-min) (point-max))))
(goto-char (point-min)))
;;;###autoload
(defun shr-render-region (begin end &optional buffer)
"Display the HTML rendering of the region between BEGIN and END."
(interactive "r")
(unless (fboundp 'libxml-parse-html-region)
(error "This function requires Emacs to be compiled with libxml2"))
(with-current-buffer (or buffer (current-buffer))
(let ((dom (libxml-parse-html-region begin end)))
(delete-region begin end)
(goto-char begin)
(shr-insert-document dom))))
(defun shr--have-one-fringe-p ()
"Return non-nil if we know at least one of the fringes has non-zero width."
(and (fboundp 'fringe-columns)
(or (not (zerop (fringe-columns 'right)))
(not (zerop (fringe-columns 'left))))))
;;;###autoload
(defun shr-insert-document (dom)
"Render the parsed document DOM into the current buffer.
DOM should be a parse tree as generated by
`libxml-parse-html-region' or similar."
(setq shr-content-cache nil)
(let ((start (point))
(shr-start nil)
(shr-base nil)
(shr-depth 0)
(shr-table-id 0)
(shr-warning nil)
(shr-table-separator-pixel-width (shr-string-pixel-width "-"))
(shr-internal-bullet (cons shr-bullet
(shr-string-pixel-width shr-bullet)))
(shr-internal-width (or (and shr-width
(if (not shr-use-fonts)
shr-width
(* shr-width (frame-char-width))))
;; We need to adjust the available
;; width for when the user disables
;; the fringes, which will cause the
;; display engine usurp one column for
;; the continuation glyph.
(if (not shr-use-fonts)
(- (window-body-width) 1
(if (and (null shr-width)
(not (shr--have-one-fringe-p)))
0
1))
(- (window-body-width nil t)
(* 2 (frame-char-width))
(if (and (null shr-width)
(not (shr--have-one-fringe-p)))
(* (frame-char-width) 2)
0)
1))))
(max-specpdl-size max-specpdl-size)
bidi-display-reordering)
;; If the window was hscrolled for some reason, shr-fill-lines
;; below will misbehave, because it silently assumes that it
;; starts with a non-hscrolled window (vertical-motion will move
;; to a wrong place otherwise).
(set-window-hscroll nil 0)
(shr-descend dom)
(shr-fill-lines start (point))
(shr--remove-blank-lines-at-the-end start (point))
(when shr-warning
(message "%s" shr-warning))))
(defun shr--remove-blank-lines-at-the-end (start end)
(save-restriction
(save-excursion
(narrow-to-region start end)
(goto-char end)
(when (and (re-search-backward "[^ \n]" nil t)
(not (eobp)))
(forward-line 1)
(delete-region (point) (point-max))))))
(defun shr-url-at-point (image-url)
"Return the URL under point as a string.
If IMAGE-URL is non-nil, or there is no link under point, but
there is an image under point then copy the URL of the image
under point instead."
(if image-url
(get-text-property (point) 'image-url)
(or (get-text-property (point) 'shr-url)
(get-text-property (point) 'image-url))))
(defun shr-copy-url (url)
"Copy the URL under point to the kill ring.
With a prefix argument, or if there is no link under point, but
there is an image under point then copy the URL of the image
under point instead."
(interactive (list (shr-url-at-point current-prefix-arg)))
(if (not url)
(message "No URL under point")
(setq url (url-encode-url url))
(kill-new url)
(message "Copied %s" url)))
(defun shr-probe-url (url cont)
"Pass URL's redirect destination to CONT, if it has one.
CONT should be a function of one argument, the redirect
destination URL. If URL is not redirected, then CONT is never
called."
(interactive "P")
(url-retrieve
url (lambda (a)
(pcase a
(`(:redirect ,destination . ,_)
;; Remove common tracking junk from the URL.
(funcall cont (replace-regexp-in-string
".utm_.*" "" destination)))))
nil t t))
(defun shr-probe-and-copy-url (url)
"Copy the URL under point to the kill ring.
Like `shr-copy-url', but additionally fetch URL and use its
redirection destination if it has one."
(interactive (list (shr-url-at-point current-prefix-arg)))
(if url (shr-probe-url url #'shr-copy-url)
(shr-copy-url url)))
(defun shr-maybe-probe-and-copy-url (url)
"Copy the URL under point to the kill ring.
If the URL is already at the front of the kill ring act like
`shr-probe-and-copy-url', otherwise like `shr-copy-url'."
(interactive (list (shr-url-at-point current-prefix-arg)))
(if (equal url (car kill-ring))
(shr-probe-and-copy-url url)
(shr-copy-url url)))
(defun shr--current-link-region ()
(let ((current (get-text-property (point) 'shr-url))
start)
(save-excursion
;; Go to the beginning.
(while (and (not (bobp))
(equal (get-text-property (point) 'shr-url) current))
(forward-char -1))
(unless (equal (get-text-property (point) 'shr-url) current)
(forward-char 1))
(setq start (point))
;; Go to the end.
(while (and (not (eobp))
(equal (get-text-property (point) 'shr-url) current))
(forward-char 1))
(list start (point)))))
(defun shr--blink-link ()
(let* ((region (shr--current-link-region))
(overlay (make-overlay (car region) (cadr region))))
(overlay-put overlay 'face 'shr-selected-link)
(run-at-time 1 nil (lambda ()
(delete-overlay overlay)))))
(defun shr-next-link ()
"Skip to the next link."
(interactive)
(let ((match (text-property-search-forward 'shr-url nil nil t)))
(if (not match)
(message "No next link")
(goto-char (prop-match-beginning match))
(message "%s" (get-text-property (point) 'help-echo)))))
(defun shr-previous-link ()
"Skip to the previous link."
(interactive)
(if (not (text-property-search-backward 'shr-url nil nil t))
(message "No previous link")
(message "%s" (get-text-property (point) 'help-echo))))
(defun shr-show-alt-text ()
"Show the ALT text of the image under point."
(interactive)
(let ((text (get-text-property (point) 'shr-alt)))
(if (not text)
(message "No image under point")
(message "%s" (shr-fill-text text)))))
(defun shr-browse-image (&optional copy-url)
"Browse the image under point.
If COPY-URL (the prefix if called interactively) is non-nil, copy
the URL of the image to the kill buffer instead."
(interactive "P")
(let ((url (get-text-property (point) 'image-url)))
(cond
((not url)
(message "No image under point"))
(copy-url
(with-temp-buffer
(insert url)
(copy-region-as-kill (point-min) (point-max))
(message "Copied %s" url)))
(t
(message "Browsing %s..." url)
(browse-url url)))))
(defun shr-insert-image ()
"Insert the image under point into the buffer."
(interactive)
(let ((url (get-text-property (point) 'image-url)))
(if (not url)
(message "No image under point")
(message "Inserting %s..." url)
(url-retrieve url 'shr-image-fetched
(list (current-buffer) (1- (point)) (point-marker))
t))))
(defun shr-zoom-image ()
"Toggle the image size.
The size will be rotated between the default size, the original
size, and full-buffer size."
(interactive)
(let ((url (get-text-property (point) 'image-url))
(size (get-text-property (point) 'image-size))
(buffer-read-only nil))
(if (not url)
(message "No image under point")
;; Delete the old picture.
(while (get-text-property (point) 'image-url)
(forward-char -1))
(forward-char 1)
(let ((start (point)))
(while (get-text-property (point) 'image-url)
(forward-char 1))
(forward-char -1)
(put-text-property start (point) 'display nil)
(when (> (- (point) start) 2)
(delete-region start (1- (point)))))
(message "Inserting %s..." url)
(url-retrieve url 'shr-image-fetched
(list (current-buffer) (1- (point)) (point-marker)
(list (cons 'size
(cond ((or (eq size 'default)
(null size))
'original)
((eq size 'original)
'full)
((eq size 'full)
'default)))))
t))))
;;; Utility functions.
(defsubst shr-generic (dom)
(dolist (sub (dom-children dom))
(if (stringp sub)
(shr-insert sub)
(shr-descend sub))))
(defun shr-indirect-call (tag-name dom &rest args)
(let ((function (intern (concat "shr-tag-" (symbol-name tag-name)) obarray))
;; Allow other packages to override (or provide) rendering
;; of elements.
(external (cdr (assq tag-name shr-external-rendering-functions))))
(cond (external
(apply external dom args))
((fboundp function)
(apply function dom args))
(t
(apply 'shr-generic dom args)))))
(defun shr-descend (dom)
(let ((function
(intern (concat "shr-tag-" (symbol-name (dom-tag dom))) obarray))
;; Allow other packages to override (or provide) rendering
;; of elements.
(external (cdr (assq (dom-tag dom) shr-external-rendering-functions)))
(style (dom-attr dom 'style))
(shr-stylesheet shr-stylesheet)
(shr-depth (1+ shr-depth))
(start (point)))
;; shr uses many frames per nested node.
(if (and (> shr-depth (/ max-specpdl-size 15))
(not (and (y-or-n-p "Too deeply nested to render properly; increase `max-specpdl-size'?")
(setq max-specpdl-size (* max-specpdl-size 2)))))
(setq shr-warning
"Not rendering the complete page because of too-deep nesting")
(when style
(if (string-match "color\\|display\\|border-collapse" style)
(setq shr-stylesheet (nconc (shr-parse-style style)
shr-stylesheet))
(setq style nil)))
;; If we have a display:none, then just ignore this part of the DOM.
(unless (or (equal (cdr (assq 'display shr-stylesheet)) "none")
(and shr-discard-aria-hidden
(equal (dom-attr dom 'aria-hidden) "true")))
;; We don't use shr-indirect-call here, since shr-descend is
;; the central bit of shr.el, and should be as fast as
;; possible. Having one more level of indirection with its
;; negative effect on performance is deemed unjustified in
;; this case.
(cond (external
(funcall external dom))
((fboundp function)
(funcall function dom))
(t
(shr-generic dom)))
(when (and shr-target-id
(equal (dom-attr dom 'id) shr-target-id))
;; If the element was empty, we don't have anything to put the
;; anchor on. So just insert a dummy character.
(when (= start (point))
(insert "*"))
(put-text-property start (1+ start) 'shr-target-id shr-target-id))
;; If style is set, then this node has set the color.
(when style
(shr-colorize-region
start (point)
(cdr (assq 'color shr-stylesheet))
(cdr (assq 'background-color shr-stylesheet))))))))
(defun shr-fill-text (text)
(if (zerop (length text))
text
(with-temp-buffer
(let ((shr-indentation 0)
(shr-start nil)
(shr-internal-width (- (window-body-width nil t)
(* 2 (frame-char-width))
;; Adjust the window width for when
;; the user disables the fringes,
;; which causes the display engine
;; to usurp one column for the
;; continuation glyph.
(if (and (null shr-width)
(not (shr--have-one-fringe-p)))
(* (frame-char-width) 2)
0))))
(shr-insert text)
(shr-fill-lines (point-min) (point-max))
(buffer-string)))))
(define-inline shr-char-breakable-p (char)
"Return non-nil if a line can be broken before and after CHAR."
(inline-quote (aref fill-find-break-point-function-table ,char)))
(define-inline shr-char-nospace-p (char)
"Return non-nil if no space is required before and after CHAR."
(inline-quote (aref fill-nospace-between-words-table ,char)))
;; KINSOKU is a Japanese word meaning a rule that should not be violated.
;; In Emacs, it is a term used for characters, e.g. punctuation marks,
;; parentheses, and so on, that should not be placed in the beginning
;; of a line or the end of a line.
(define-inline shr-char-kinsoku-bol-p (char)
"Return non-nil if a line ought not to begin with CHAR."
(inline-letevals (char)
(inline-quote (and (not (eq ,char ?'))
(aref (char-category-set ,char) ?>)))))
(define-inline shr-char-kinsoku-eol-p (char)
"Return non-nil if a line ought not to end with CHAR."
(inline-quote (aref (char-category-set ,char) ?<)))
(unless (shr-char-kinsoku-bol-p (make-char 'japanese-jisx0208 33 35))
(load "kinsoku" nil t))
(defun shr-pixel-column ()
(if (not shr-use-fonts)
(current-column)
(if (not (get-buffer-window (current-buffer)))
(save-window-excursion
;; Avoid errors if the selected window is a dedicated one,
;; and they just want to insert a document into it.
(set-window-dedicated-p nil nil)
(set-window-buffer nil (current-buffer))
(car (window-text-pixel-size nil (line-beginning-position) (point))))
(car (window-text-pixel-size nil (line-beginning-position) (point))))))
(defun shr-pixel-region ()
(- (shr-pixel-column)
(save-excursion
(goto-char (mark))
(shr-pixel-column))))
(defun shr-string-pixel-width (string)
(if (not shr-use-fonts)
(length string)
;; Save and restore point across with-temp-buffer, since
;; shr-pixel-column uses save-window-excursion, which can reset
;; point to 1.
(let ((pt (point)))
(prog1
(with-temp-buffer
(insert string)
(shr-pixel-column))
(goto-char pt)))))
(defsubst shr--translate-insertion-chars ()
;; Remove soft hyphens.
(goto-char (point-min))
(while (search-forward "" nil t)
(replace-match "" t t))
;; Translate non-breaking spaces into real spaces.
(goto-char (point-min))
(while (search-forward " " nil t)
(replace-match " " t t)))
(defun shr-insert (text)
(when (and (not (bolp))
(get-text-property (1- (point)) 'image-url))
(insert "\n"))
(cond
((eq shr-folding-mode 'none)
(let ((start (point)))
(insert text)
(save-restriction
(narrow-to-region start (point))
(shr--translate-insertion-chars)
(goto-char (point-max)))))
(t
(let ((font-start (point)))
(when (and (string-match "\\`[ \t\n\r]" text)
(not (bolp))
(not (eq (char-after (1- (point))) ? )))
(insert " "))
(let ((start (point))
(bolp (bolp)))
(insert text)
(save-restriction
(narrow-to-region start (point))
(goto-char start)
(when (looking-at "[ \t\n\r]+")
(replace-match "" t t))
(while (re-search-forward "[ \t\n\r]+" nil t)
(replace-match " " t t))
(shr--translate-insertion-chars)
(goto-char (point-max)))
;; We may have removed everything we inserted if it was just
;; spaces.
(unless (= font-start (point))
;; Mark all lines that should possibly be folded afterwards.
(when bolp
(shr-mark-fill start))
(when shr-use-fonts
(put-text-property font-start (point)
'face
(or shr-current-font 'variable-pitch)))))))))
(defun shr-fill-lines (start end)
(if (<= shr-internal-width 0)
nil
(save-restriction
(narrow-to-region start end)
(goto-char start)
(when (get-text-property (point) 'shr-indentation)
(shr-fill-line))
(while (setq start (next-single-property-change start 'shr-indentation))
(goto-char start)
(when (bolp)
(shr-fill-line)))
(goto-char (point-max)))))
(defun shr-vertical-motion (column)
(if (not shr-use-fonts)
(move-to-column column)
(unless (eolp)
(forward-char 1))
(vertical-motion (cons (/ column (frame-char-width)) 0))
(unless (eolp)
(forward-char 1))))
(defun shr-fill-line ()
(let ((shr-indentation (get-text-property (point) 'shr-indentation))
(continuation (get-text-property
(point) 'shr-continuation-indentation))
start)
(put-text-property (point) (1+ (point)) 'shr-indentation nil)
(let ((face (get-text-property (point) 'face))
(background-start (point)))
(shr-indent)
(when face
(put-text-property background-start (point) 'face
`,(shr-face-background face))))
(setq start (point))
(setq shr-indentation (or continuation shr-indentation))
;; If we have an indentation that's wider than the width we're
;; trying to fill to, then just give up and don't do any filling.
(when (< shr-indentation shr-internal-width)
(shr-vertical-motion shr-internal-width)
(when (looking-at " $")
(delete-region (point) (line-end-position)))
(while (not (eolp))
;; We have to do some folding. First find the first
;; previous point suitable for folding.
(if (or (not (shr-find-fill-point (line-beginning-position)))
(= (point) start))
;; We had unbreakable text (for this width), so just go to
;; the first space and carry on.
(progn
(beginning-of-line)
(skip-chars-forward " ")
(search-forward " " (line-end-position) 'move)))
;; Success; continue.
(when (= (preceding-char) ?\s)
(delete-char -1))
(let ((gap-start (point))
(face (get-text-property (point) 'face)))
;; Extend the background to the end of the line.
(if face
(insert (propertize "\n" 'face (shr-face-background face)))
(insert "\n"))
(shr-indent)
(when (and (> (1- gap-start) (point-min))
(get-text-property (point) 'shr-url)
;; The link on both sides of the newline are the
;; same...
(equal (get-text-property (point) 'shr-url)
(get-text-property (1- gap-start) 'shr-url)))
;; ... so we join the two bits into one link logically, but
;; not visually. This makes navigation between links work
;; well, but avoids underscores before the link on the next
;; line when indented.
(let* ((props (copy-sequence (text-properties-at (point))))
(face (plist-get props 'face)))
;; We don't want to use the faces on the indentation, because
;; that's ugly, but we do want to use the background colour.
(when face
(setq props (plist-put props 'face (shr-face-background face))))
(add-text-properties gap-start (point) props))))
(setq start (point))
(shr-vertical-motion shr-internal-width)
(when (looking-at " $")
(delete-region (point) (line-end-position)))))))
(defun shr-find-fill-point (start)
(let ((bp (point))
(end (point))
failed)
(while (not (or (setq failed (<= (point) start))
(eq (preceding-char) ? )
(eq (following-char) ? )
(shr-char-breakable-p (preceding-char))
(shr-char-breakable-p (following-char))
(and (shr-char-kinsoku-bol-p (preceding-char))
(shr-char-breakable-p (following-char))
(not (shr-char-kinsoku-bol-p (following-char))))
(shr-char-kinsoku-eol-p (following-char))
(bolp)))
(backward-char 1))
(if failed
;; There's no breakable point, so we give it up.
(let (found)
(goto-char bp)
;; Don't overflow the window edge, even if
;; shr-kinsoku-shorten is nil.
(unless (or shr-kinsoku-shorten (null shr-width))
(while (setq found (re-search-forward
"\\(\\c>\\)\\| \\|\\c<\\|\\c|"
(line-end-position) 'move)))
(if (and found
(not (match-beginning 1)))
(goto-char (match-beginning 0)))))
(or
(eolp)
;; Don't put kinsoku-bol characters at the beginning of a line,
;; or kinsoku-eol characters at the end of a line.
(cond
;; Don't overflow the window edge, even if shr-kinsoku-shorten
;; is nil.
((or shr-kinsoku-shorten (null shr-width))
(while (and (not (memq (preceding-char) (list ?\C-@ ?\n ? )))
(or (shr-char-kinsoku-eol-p (preceding-char))
(shr-char-kinsoku-bol-p (following-char))))
(backward-char 1))
(when (setq failed (<= (point) start))
;; There's no breakable point that doesn't violate kinsoku,
;; so we look for the second best position.
(while (and (progn
(forward-char 1)
(<= (point) end))
(progn
(setq bp (point))
(shr-char-kinsoku-eol-p (following-char)))))
(goto-char bp)))
((shr-char-kinsoku-eol-p (preceding-char))
;; Find backward the point where kinsoku-eol characters begin.
(let ((count 4))
(while
(progn
(backward-char 1)
(and (> (setq count (1- count)) 0)
(not (memq (preceding-char) (list ?\C-@ ?\n ? )))
(or (shr-char-kinsoku-eol-p (preceding-char))
(shr-char-kinsoku-bol-p (following-char)))))))
(when (setq failed (<= (point) start))
;; There's no breakable point that doesn't violate kinsoku,
;; so we go to the second best position.
(if (looking-at "\\(\\c<+\\)\\c<")
(goto-char (match-end 1))
(forward-char 1))))
((shr-char-kinsoku-bol-p (following-char))
;; Find forward the point where kinsoku-bol characters end.
(let ((count 4))
(while (progn
(forward-char 1)
(and (>= (setq count (1- count)) 0)
(shr-char-kinsoku-bol-p (following-char))
(shr-char-breakable-p (following-char))))))))
(when (eq (following-char) ? )
(forward-char 1))))
(not failed)))
(defun shr-parse-base (url)
;; Always chop off anchors.
(when (string-match "#.*" url)
(setq url (substring url 0 (match-beginning 0))))
;; NB: URI may itself be relative to the document s URI
(setq url (shr-expand-url url))
(let* ((parsed (url-generic-parse-url url))
(local (url-filename parsed)))
(setf (url-filename parsed) "")
;; Chop off the bit after the last slash.
(when (string-match "\\`\\(.*/\\)[^/]+\\'" local)
(setq local (match-string 1 local)))
;; Always make the local bit end with a slash.
(when (and (not (zerop (length local)))
(not (eq (aref local (1- (length local))) ?/)))
(setq local (concat local "/")))
(list (url-recreate-url parsed)
local
(url-type parsed)
url)))
(autoload 'url-expand-file-name "url-expand")
;; FIXME This needs some tests writing.
;; Does it even need to exist, given that url-expand-file-name does?
(defun shr-expand-url (url &optional base)
(setq base
(if base
;; shr-parse-base should never call this with non-nil base!
(shr-parse-base base)
;; Bound by the parser.
shr-base))
(when (zerop (length url))
(setq url nil))
;; Strip leading whitespace
(and url (string-match "\\`\\s-+" url)
(setq url (substring url (match-end 0))))
(cond ((zerop (length url))
(nth 3 base))
((or (not base)
(string-match "\\`[a-z]*:" url))
;; Absolute or empty URI
url)
((eq (aref url 0) ?/)
(if (and (> (length url) 1)
(eq (aref url 1) ?/))
;; //host...; just use the protocol
(concat (nth 2 base) ":" url)
;; Just use the host name part.
(concat (car base) url)))
((eq (aref url 0) ?#)
;; A link to an anchor.
(concat (nth 3 base) url))
(t
;; Totally relative.
(url-expand-file-name url (concat (car base) (cadr base))))))
(defun shr-ensure-newline ()
(unless (bobp)
(let ((prefix (get-text-property (line-beginning-position)
'shr-prefix-length)))
(unless (or (zerop (current-column))
(and prefix
(= prefix (- (point) (line-beginning-position)))))
(insert "\n")))))
(defun shr-ensure-paragraph ()
(unless (bobp)
(let ((prefix (get-text-property (line-beginning-position)
'shr-prefix-length)))
(cond
((and (bolp)
(save-excursion
(forward-line -1)
(looking-at " *$")))
;; We're already at a new paragraph; do nothing.
)
((and prefix
(= prefix (- (point) (line-beginning-position))))
;; Do nothing; we're at the start of a
.
)
((save-excursion
(beginning-of-line)
;; If the current line is totally blank, and doesn't even
;; have any face properties set, then delete the blank
;; space.
(and (looking-at " *$")
(not (get-text-property (point) 'face))
(not (= (next-single-property-change (point) 'face nil
(line-end-position))
(line-end-position)))))
(delete-region (match-beginning 0) (match-end 0)))
;; We have a single blank line.
((and (eolp) (bolp))
(insert "\n"))
;; Insert new paragraph.
(t
(insert "\n\n"))))))
(defun shr-indent ()
(when (> shr-indentation 0)
(insert
(if (not shr-use-fonts)
(make-string shr-indentation ?\s)
(propertize " "
'display
`(space :width (,shr-indentation)))))))
(defun shr-fontize-dom (dom &rest types)
(let ((start (point)))
(shr-generic dom)
(dolist (type types)
(shr-add-font start (point) type))))
;; Add face to the region, but avoid putting the font properties on
;; blank text at the start of the line, and the newline at the end, to
;; avoid ugliness.
(defun shr-add-font (start end type)
(save-excursion
(goto-char start)
(while (< (point) end)
(when (bolp)
(skip-chars-forward " "))
(add-face-text-property (point) (min (line-end-position) end) type t)
(if (< (line-end-position) end)
(forward-line 1)
(goto-char end)))))
(defun shr-mouse-browse-url (ev)
"Browse the URL under the mouse cursor."
(interactive "e")
(mouse-set-point ev)
(shr-browse-url))
(defun shr-mouse-browse-url-new-window (ev)
"Browse the URL under the mouse cursor in a new window."
(interactive "e")
(mouse-set-point ev)
(shr-browse-url nil nil t))
(defun shr-browse-url (&optional external mouse-event new-window)
"Browse the URL at point using `browse-url'.
If EXTERNAL is non-nil (interactively, the prefix argument), browse
the URL using `browse-url-secondary-browser-function'.
If this function is invoked by a mouse click, it will browse the URL
at the position of the click. Optional argument MOUSE-EVENT describes
the mouse click event."
(interactive (list current-prefix-arg last-nonmenu-event))
(mouse-set-point mouse-event)
(let ((url (get-text-property (point) 'shr-url)))
(cond
((not url)
(message "No link under point"))
((string-match "^mailto:" url)
(browse-url-mail url))
(t
(if external
(progn
(funcall browse-url-secondary-browser-function url)
(shr--blink-link))
(browse-url url (if new-window
(not browse-url-new-window-flag)
browse-url-new-window-flag)))))))
(defun shr-save-contents (directory)
"Save the contents from URL in a file."
(interactive "DSave contents of URL to directory: ")
(let ((url (get-text-property (point) 'shr-url)))
(if (not url)
(message "No link under point")
(url-retrieve (shr-encode-url url)
'shr-store-contents (list url directory)))))
(defun shr-store-contents (status url directory)
(unless (plist-get status :error)
(when (or (search-forward "\n\n" nil t)
(search-forward "\r\n\r\n" nil t))
(write-region (point) (point-max)
(expand-file-name (file-name-nondirectory url)
directory)))))
(defun shr-image-fetched (status buffer start end &optional flags)
(let ((image-buffer (current-buffer)))
(when (and (buffer-name buffer)
(not (plist-get status :error)))
(url-store-in-cache image-buffer)
(goto-char (point-min))
(when (or (search-forward "\n\n" nil t)
(search-forward "\r\n\r\n" nil t))
(let ((data (shr-parse-image-data)))
(with-current-buffer buffer
(save-excursion
(save-restriction
(widen)
(let ((alt (buffer-substring start end))
(properties (text-properties-at start))
(inhibit-read-only t))
(delete-region start end)
(goto-char start)
(funcall shr-put-image-function data alt flags)
(while properties
(let ((type (pop properties))
(value (pop properties)))
(unless (memq type '(display image-size))
(put-text-property start (point) type value)))))))))))
(kill-buffer image-buffer)))
(defun shr-image-from-data (data)
"Return an image from the data: URI content DATA."
(when (string-match
"\\(\\([^/;,]+\\(/[^;,]+\\)?\\)\\(;[^;,]+\\)*\\)?,\\(.*\\)"
data)
(let ((param (match-string 4 data))
(payload (url-unhex-string (match-string 5 data))))
(when (and param
(string-match "^.*\\(;[ \t]*base64\\)$" param))
(setq payload (ignore-errors
(base64-decode-string payload))))
payload)))
;; Behind display-graphic-p test.
(declare-function image-size "image.c" (spec &optional pixels frame))
(declare-function image-animate "image" (image &optional index limit))
(defun shr-put-image (spec alt &optional flags)
"Insert image SPEC with a string ALT. Return image.
SPEC is either an image data blob, or a list where the first
element is the data blob and the second element is the content-type."
(if (display-graphic-p)
(let* ((size (cdr (assq 'size flags)))
(data (if (consp spec)
(car spec)
spec))
(content-type (and (consp spec)
(cadr spec)))
(start (point))
(image (cond
((eq size 'original)
(create-image data nil t :ascent 100
:format content-type))
((eq content-type 'image/svg+xml)
(when (image-type-available-p 'svg)
(create-image data 'svg t :ascent 100)))
((eq size 'full)
(ignore-errors
(shr-rescale-image data content-type
(plist-get flags :width)
(plist-get flags :height))))
(t
(ignore-errors
(shr-rescale-image data content-type
(plist-get flags :width)
(plist-get flags :height)))))))
(when image
;; When inserting big-ish pictures, put them at the
;; beginning of the line.
(when (and (> (current-column) 0)
(> (car (image-size image t)) 400))
(insert "\n"))
(if (eq size 'original)
(insert-sliced-image image (or alt "*") nil 20 1)
(insert-image image (or alt "*")))
(put-text-property start (point) 'image-size size)
(when (and shr-image-animate
(cdr (image-multi-frame-p image)))
(image-animate image nil 60)))
image)
(insert (or alt ""))))
(defun shr--image-type ()
"Emacs image type to use when displaying images.
If Emacs has native image scaling support, that's used, but if
not, `imagemagick' is preferred if it's present."
(if (or (and (fboundp 'image-transforms-p)
(image-transforms-p))
(not (fboundp 'imagemagick-types)))
nil
'imagemagick))
(defun shr-rescale-image (data content-type width height
&optional max-width max-height)
"Rescale DATA, if too big, to fit the current buffer.
WIDTH and HEIGHT are the sizes given in the HTML data, if any.
The size of the displayed image will not exceed
MAX-WIDTH/MAX-HEIGHT. If not given, use the current window
width/height instead."
(if (not (get-buffer-window (current-buffer) t))
(create-image data nil t :ascent 100)
(let* ((edges (window-inside-pixel-edges
(get-buffer-window (current-buffer))))
(max-width (truncate (* shr-max-image-proportion
(or max-width
(- (nth 2 edges) (nth 0 edges))))))
(max-height (truncate (* shr-max-image-proportion
(or max-height
(- (nth 3 edges) (nth 1 edges))))))
(scaling (image-compute-scaling-factor image-scaling-factor)))
(when (or (and width
(> width max-width))
(and height
(> height max-height)))
(setq width nil
height nil))
(if (and width height
(< (* width scaling) max-width)
(< (* height scaling) max-height))
(create-image
data (shr--image-type) t
:ascent 100
:width width
:height height
:format content-type)
(create-image
data (shr--image-type) t
:ascent 100
:max-width max-width
:max-height max-height
:format content-type)))))
;; url-cache-extract autoloads url-cache.
(declare-function url-cache-create-filename "url-cache" (url))
(autoload 'browse-url-mail "browse-url")
(defun shr-get-image-data (url)
"Get image data for URL.
Return a string with image data."
(with-temp-buffer
(set-buffer-multibyte nil)
(when (ignore-errors
(url-cache-extract (url-cache-create-filename (shr-encode-url url)))
t)
(when (re-search-forward "\r?\n\r?\n" nil t)
(shr-parse-image-data)))))
(declare-function libxml-parse-xml-region "xml.c"
(start end &optional base-url discard-comments))
(defun shr-parse-image-data ()
(let ((data (buffer-substring (point) (point-max)))
(content-type
(save-excursion
(save-restriction
(narrow-to-region (point-min) (point))
(let ((content-type (mail-fetch-field "content-type")))
(and content-type
;; Remove any comments in the type string.
(intern (replace-regexp-in-string ";.*" "" content-type)
obarray)))))))
;; SVG images may contain references to further images that we may
;; want to block. So special-case these by parsing the XML data
;; and remove anything that looks like a blocked bit.
(when (and shr-blocked-images
(eq content-type 'image/svg+xml))
(setq data
;; Note that libxml2 doesn't parse everything perfectly,
;; so glitches may occur during this transformation. And
;; encode as utf-8: There may be text (and other elements)
;; that are non-ASCII.
(shr-dom-to-xml
(libxml-parse-xml-region (point) (point-max)) 'utf-8)))
;; SVG images often do not have a specified foreground/background
;; color, so wrap them in styles.
(when (eq content-type 'image/svg+xml)
(setq data (svg--wrap-svg data)))
(list data content-type)))
(defun svg--wrap-svg (data)
"Add a default foreground colour to SVG images."
(let ((size (image-size (create-image data nil t :scaling 1) t)))
(with-temp-buffer
(insert
(format
""
(face-foreground 'default)
(car size) (cdr size)
(base64-encode-string data t)))
(buffer-string))))
(defun shr-image-displayer (content-function)
"Return a function to display an image.
CONTENT-FUNCTION is a function to retrieve an image for a cid url that
is an argument. The function to be returned takes three arguments URL,
START, and END. Note that START and END should be markers."
`(lambda (url start end)
(when url
(if (string-match "\\`cid:" url)
,(when content-function
`(let ((image (funcall ,content-function
(substring url (match-end 0)))))
(when image
(goto-char start)
(funcall shr-put-image-function
image (buffer-substring start end))
(delete-region (point) end))))
(url-retrieve url 'shr-image-fetched
(list (current-buffer) start end)
t t)))))
(defun shr-heading (dom &rest types)
(shr-ensure-paragraph)
(apply #'shr-fontize-dom dom types)
(shr-ensure-paragraph))
(defun shr-urlify (start url &optional title)
(shr-add-font start (point) 'shr-link)
(add-text-properties
start (point)
(list 'shr-url url
'button t
'category 'shr ; For button.el button buffers.
'help-echo (let ((parsed (url-generic-parse-url
(or (ignore-errors
(decode-coding-string
(url-unhex-string url)
'utf-8 t))
url)))
iri)
;; If we have an IDNA domain, then show the
;; decoded version in the mouseover to let the
;; user know that there's something possibly
;; fishy.
(when (url-host parsed)
(setf (url-host parsed)
(puny-encode-domain (url-host parsed))))
(setq iri (url-recreate-url parsed))
(if title
(format "%s (%s)" iri title)
iri))
'follow-link t
'mouse-face 'highlight))
;; Don't overwrite any keymaps that are already in the buffer (i.e.,
;; image keymaps).
(while (and start
(< start (point)))
(let ((next (next-single-property-change start 'keymap nil (point))))
(if (get-text-property start 'keymap)
(setq start next)
(put-text-property start (or next (point)) 'keymap shr-map)))))
(defun shr-encode-url (url)
"Encode URL."
(browse-url-url-encode-chars url "[)$ ]"))
(autoload 'shr-color-visible "shr-color")
(autoload 'shr-color->hexadecimal "shr-color")
(defun shr-color-check (fg bg)
"Check that FG is visible on BG.
Returns (fg bg) with corrected values.
Returns nil if the colors that would be used are the default
ones, in case fg and bg are nil."
(when (or fg bg)
(let ((fixed (cond ((null fg) 'fg)
((null bg) 'bg))))
;; Convert colors to hexadecimal, or set them to default.
(let ((fg (or (shr-color->hexadecimal fg)
(frame-parameter nil 'foreground-color)))
(bg (or (shr-color->hexadecimal bg)
(frame-parameter nil 'background-color))))
(cond ((eq fixed 'bg)
;; Only return the new fg
(list nil (cadr (shr-color-visible bg fg t))))
((eq fixed 'fg)
;; Invert args and results and return only the new bg
(list (cadr (shr-color-visible fg bg t)) nil))
(t
(shr-color-visible bg fg)))))))
(defun shr-colorize-region (start end fg &optional bg)
(when (and shr-use-colors
(or fg bg)
(>= (display-color-cells) 88))
(let ((new-colors (shr-color-check fg bg)))
(when new-colors
(when fg
(add-face-text-property start end
(list :foreground (cadr new-colors))
t))
(when bg
(add-face-text-property start end
(list :background (car new-colors))
t)))
new-colors)))
;;; Tag-specific rendering rules.
(defun shr-tag-html (dom)
(let ((dir (dom-attr dom 'dir)))
(cond
((equal dir "ltr")
(setq bidi-paragraph-direction 'left-to-right))
((equal dir "rtl")
(setq bidi-paragraph-direction 'right-to-left))
((equal dir "auto")
(setq bidi-paragraph-direction nil))))
(shr-generic dom))
(defun shr-tag-body (dom)
(let* ((start (point))
(fgcolor (or (dom-attr dom 'fgcolor) (dom-attr dom 'text)))
(bgcolor (dom-attr dom 'bgcolor))
(shr-stylesheet (list (cons 'color fgcolor)
(cons 'background-color bgcolor))))
(shr-generic dom)
(shr-colorize-region start (point) fgcolor bgcolor)))
(defun shr-tag-style (_dom)
)
(defun shr-tag-script (_dom)
)
(defun shr-tag-comment (_dom)
)
(defun shr-dom-to-xml (dom &optional charset)
(with-temp-buffer
(shr-dom-print dom)
(when charset
(encode-coding-region (point-min) (point-max) charset)
(goto-char (point-min))
(insert (format "\n"
charset)))
(buffer-string)))
(defun shr-dom-print (dom)
"Convert DOM into a string containing the xml representation."
(insert (format "<%s" (dom-tag dom)))
(dolist (attr (dom-attributes dom))
;; Ignore attributes that start with a colon because they are
;; private elements.
(unless (= (aref (format "%s" (car attr)) 0) ?:)
(insert (format " %s=\"%s\"" (car attr) (cdr attr)))))
(insert ">")
(let (url)
(dolist (elem (dom-children dom))
(cond
((stringp elem)
(insert elem))
((eq (dom-tag elem) 'comment)
)
((or (not (eq (dom-tag elem) 'image))
;; Filter out blocked elements inside the SVG image.
(not (setq url (dom-attr elem ':xlink:href)))
(not shr-blocked-images)
(not (string-match shr-blocked-images url)))
(insert " ")
(shr-dom-print elem)))))
(insert (format "%s>" (dom-tag dom))))
(defun shr-tag-svg (dom)
(when (and (image-type-available-p 'svg)
(not shr-inhibit-images)
(dom-attr dom 'width)
(dom-attr dom 'height))
(funcall shr-put-image-function (list (shr-dom-to-xml dom 'utf-8)
'image/svg+xml)
"SVG Image")))
(defun shr-tag-sup (dom)
(let ((start (point)))
(shr-generic dom)
(put-text-property start (point) 'display '(raise 0.2))))
(defun shr-tag-sub (dom)
(let ((start (point)))
(shr-generic dom)
(put-text-property start (point) 'display '(raise -0.2))))
(defun shr-tag-p (dom)
(shr-ensure-paragraph)
(shr-generic dom)
(shr-ensure-paragraph))
(defun shr-tag-div (dom)
(let ((display (cdr (assq 'display shr-stylesheet))))
(if (or (equal display "inline")
(equal display "inline-block"))
(shr-generic dom)
(shr-ensure-newline)
(shr-generic dom)
(shr-ensure-newline))))
(defun shr-tag-s (dom)
(shr-fontize-dom dom 'shr-strike-through))
(defun shr-tag-b (dom)
(shr-fontize-dom dom 'bold))
(defun shr-tag-i (dom)
(shr-fontize-dom dom 'italic))
(defun shr-tag-em (dom)
(shr-fontize-dom dom 'italic))
(defun shr-tag-strong (dom)
(shr-fontize-dom dom 'bold))
(defun shr-tag-u (dom)
(shr-fontize-dom dom 'underline))
(defun shr-tag-code (dom)
(let ((shr-current-font 'default))
(shr-generic dom)))
(defun shr-tag-tt (dom)
;; The `tt' tag is deprecated in favor of `code'.
(shr-tag-code dom))
(defun shr-tag-ins (cont)
(let* ((start (point))
(color "green")
(shr-stylesheet (nconc (list (cons 'color color))
shr-stylesheet)))
(shr-generic cont)
(shr-colorize-region start (point) color
(cdr (assq 'background-color shr-stylesheet)))))
(defun shr-tag-del (cont)
(let* ((start (point))
(color "red")
(shr-stylesheet (nconc (list (cons 'color color))
shr-stylesheet)))
(shr-fontize-dom cont 'shr-strike-through)
(shr-colorize-region start (point) color
(cdr (assq 'background-color shr-stylesheet)))))
(defun shr-parse-style (style)
(when style
(save-match-data
(when (string-match "\n" style)
(setq style (replace-match " " t t style))))
(let ((plist nil))
(dolist (elem (split-string style ";"))
(when elem
(setq elem (split-string elem ":"))
(when (and (car elem)
(cadr elem))
(let ((name (replace-regexp-in-string "^ +\\| +$" "" (car elem)))
(value (replace-regexp-in-string "^ +\\| +$" "" (cadr elem))))
(when (string-match " *!important\\'" value)
(setq value (substring value 0 (match-beginning 0))))
(unless (equal value "inherit")
(push (cons (intern name obarray)
value)
plist))))))
plist)))
(defun shr-tag-base (dom)
(when-let* ((base (dom-attr dom 'href)))
(setq shr-base (shr-parse-base base)))
(shr-generic dom))
(defun shr-tag-a (dom)
(let ((url (dom-attr dom 'href))
(title (dom-attr dom 'title))
(start (point))
shr-start)
(shr-generic dom)
(when (and shr-target-id
(equal (dom-attr dom 'name) shr-target-id))
;; We have a zero-length element, so just
;; insert... something.
(when (= start (point))
(shr-ensure-newline)
(insert " "))
(put-text-property start (1+ start) 'shr-target-id shr-target-id))
(when url
(shr-urlify (or shr-start start) (shr-expand-url url) title))))
(defun shr-tag-abbr (dom)
(when-let* ((title (dom-attr dom 'title))
(start (point)))
(shr-generic dom)
(shr-add-font start (point) 'shr-abbreviation)
(add-text-properties
start (point)
(list
'help-echo title
'mouse-face 'highlight))))
(defun shr-tag-acronym (dom)
;; `acronym' is deprecated in favor of `abbr'.
(shr-tag-abbr dom))
(defun shr-tag-object (dom)
(unless shr-inhibit-images
(let ((start (point))
url multimedia image)
(when-let* ((type (dom-attr dom 'type)))
(when (string-match "\\`image/svg" type)
(setq url (dom-attr dom 'data)
image t)))
(dolist (child (dom-non-text-children dom))
(cond
((eq (dom-tag child) 'embed)
(setq url (or url (dom-attr child 'src))
multimedia t))
((and (eq (dom-tag child) 'param)
(equal (dom-attr child 'name) "movie"))
(setq url (or url (dom-attr child 'value))
multimedia t))))
(when url
(cond
(image
(shr-indirect-call 'img dom url)
(setq dom nil))
(multimedia
(shr-insert " [multimedia] ")
(shr-urlify start (shr-expand-url url)))))
(when dom
(shr-generic dom)))))
(defcustom shr-prefer-media-type-alist '(("webm" . 1.0)
("ogv" . 1.0)
("ogg" . 1.0)
("opus" . 1.0)
("flac" . 0.9)
("wav" . 0.5))
"Preferences for media types.
The key element should be a regexp matched against the type of the source or
url if no type is specified. The value should be a float in the range 0.0 to
1.0. Media elements with higher value are preferred."
:version "24.4"
:type '(alist :key-type regexp :value-type float))
(defun shr--get-media-pref (elem)
"Determine the preference for ELEM.
The preference is a float determined from `shr-prefer-media-type'."
(let ((type (dom-attr elem 'type))
(p 0.0))
(unless type
(setq type (dom-attr elem 'src)))
(when type
(dolist (pref shr-prefer-media-type-alist)
(when (and
(> (cdr pref) p)
(string-match-p (car pref) type))
(setq p (cdr pref)))))
p))
(defun shr--extract-best-source (dom &optional url pref)
"Extract the best `:src' property from