1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
|
;;; gnus-html.el --- Quoted-Printable functions
;; Copyright (C) 2010 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 <http://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))
(eval-when-compile (require 'mm-decode))
(require 'mm-url)
(defcustom gnus-html-cache-directory (nnheader-concat gnus-directory "html-cache/")
"Where Gnus will cache images it downloads from the web."
:version "24.1"
:group 'gnus-art
:type 'directory)
(defcustom gnus-html-cache-size 500000000
"The size of the Gnus image cache."
:version "24.1"
:group 'gnus-art
:type 'integer)
(defcustom gnus-html-frame-width 70
"What width to use when rendering HTML."
:version "24.1"
:group 'gnus-art
:type 'integer)
(defcustom gnus-blocked-images "."
"Images that have URLs matching this regexp will be blocked."
:version "24.1"
:group 'gnus-art
:type 'regexp)
(defcustom gnus-max-image-proportion 0.7
"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)
;;;###autoload
(defun gnus-article-html (handle)
(let ((article-buffer (current-buffer)))
(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))
(not (eq charset 'ascii)))
(insert (prog1
(mm-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" "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-wash-tags ()
(let (tag parameters string start end images url)
(mm-url-decode-entities)
(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 "<\\([^ />]+\\)\\([^>]*\\)>" nil t)
(setq tag (match-string 1)
parameters (match-string 2)
start (match-beginning 0))
(when (plusp (length parameters))
(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")
(when (string-match "src=\"\\([^\"]+\\)" parameters)
(setq url (match-string 1 parameters))
(gnus-message 8 "gnus-html-wash-tags: fetching image URL %s" 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
(setq url (match-string 1 url))))
image)
(when handle
(mm-with-part handle
(setq image (gnus-create-image (buffer-string)
nil t))))
(when image
(let ((string (buffer-substring start end)))
(delete-region start end)
(gnus-put-image image (gnus-string-or string "*")))))
;; Normal, external URL.
(unless (gnus-html-image-url-blocked-p
url
(if (buffer-live-p gnus-summary-buffer)
(with-current-buffer gnus-summary-buffer
gnus-blocked-images)
gnus-blocked-images))
(let ((file (gnus-html-image-id url))
width height)
(when (string-match "height=\"?\\([0-9]+\\)" parameters)
(setq height (string-to-number (match-string 1 parameters))))
(when (string-match "width=\"?\\([0-9]+\\)" parameters)
(setq width (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)))
(if (file-exists-p file)
;; It's already cached, so just insert it.
(let ((string (buffer-substring start end)))
;; Delete the ALT text.
(delete-region start end)
(gnus-html-put-image file (point) string))
;; We don't have it, so schedule it for fetching
;; asynchronously.
(push (list url
(set-marker (make-marker) start)
(point-marker))
images))))))))
;; 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 url
url)
(let ((overlay (gnus-make-overlay start end)))
(gnus-overlay-put overlay 'evaporate t)
(gnus-overlay-put overlay 'gnus-button-url url)
(when gnus-article-mouse-face
(gnus-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))
;; 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>" nil t)
(replace-match "" t t))
(when images
(gnus-html-schedule-image-fetching (current-buffer) (nreverse images)))))
(defun gnus-html-schedule-image-fetching (buffer images)
(gnus-message 8 "gnus-html-schedule-image-fetching: buffer %s, images %s"
buffer images)
(let* ((url (caar images))
(process (start-process
"images" nil "curl"
"-s" "--create-dirs"
"--location"
"--max-time" "60"
"-o" (gnus-html-image-id url)
url)))
(process-kill-without-query process)
(set-process-sentinel process 'gnus-html-curl-sentinel)
(gnus-set-process-plist process (list 'images images
'buffer buffer))))
(defun gnus-html-image-id (url)
(expand-file-name (sha1 url) gnus-html-cache-directory))
(defun gnus-html-curl-sentinel (process event)
(when (string-match "finished" event)
(let* ((images (gnus-process-get process 'images))
(buffer (gnus-process-get process 'buffer))
(spec (pop images))
(file (gnus-html-image-id (car spec))))
(when (and (buffer-live-p buffer)
;; If the position of the marker is 1, then that
;; means that the text it was in has been deleted;
;; i.e., that the user has selected a different
;; article before the image arrived.
(not (= (marker-position (cadr spec)) (point-min))))
(with-current-buffer buffer
(let ((inhibit-read-only t)
(string (buffer-substring (cadr spec) (caddr spec))))
(delete-region (cadr spec) (caddr spec))
(gnus-html-put-image file (cadr spec) string))))
(when images
(gnus-html-schedule-image-fetching buffer images)))))
(defun gnus-html-put-image (file point string)
(when (display-graphic-p)
(let ((image (ignore-errors
(gnus-create-image file))))
(save-excursion
(goto-char point)
(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 (image-size image t)) 30)
(= (cdr (image-size image t)) 30))))
(progn
(gnus-put-image (gnus-html-rescale-image image)
(gnus-string-or string "*"))
t)
(insert string)
(when (fboundp 'find-image)
(gnus-put-image (find-image
'((:type xpm :file "lock-broken.xpm")))
(gnus-string-or string "*")))
nil)))))
(defun gnus-html-rescale-image (image)
(if (or (not (fboundp 'imagemagick-types))
(not (get-buffer-window (current-buffer))))
image
(let* ((width (car (image-size image t)))
(height (cdr (image-size image t)))
(edges (window-pixel-edges (get-buffer-window (current-buffer))))
(window-width (truncate (* gnus-max-image-proportion
(- (nth 2 edges) (nth 0 edges)))))
(window-height (truncate (* gnus-max-image-proportion
(- (nth 3 edges) (nth 1 edges)))))
scaled-image)
(when (> height window-height)
(setq image (or (create-image file 'imagemagick nil
:height window-height)
image))
(when (> (car (image-size image t)) window-width)
(setq image (or
(create-image file 'imagemagick nil
:width window-width)
image))))
image)))
(defun gnus-html-prune-cache ()
(let ((total-size 0)
files)
(dolist (file (directory-files gnus-html-cache-directory t nil t))
(let ((attributes (file-attributes file)))
(unless (nth 0 attributes)
(incf total-size (nth 7 attributes))
(push (list (time-to-seconds (nth 5 attributes))
(nth 7 attributes) file)
files))))
(when (> total-size gnus-html-cache-size)
(setq files (sort files (lambda (f1 f2)
(< (car f1) (car f2)))))
(dolist (file files)
(when (> total-size gnus-html-cache-size)
(decf total-size (cadr file))
(delete-file (nth 2 file)))))))
(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)
(let (blocked-images urls)
(when (buffer-live-p summary)
(with-current-buffer summary
(setq blocked-images gnus-blocked-images))
(save-match-data
(while (re-search-forward "<img.*src=[\"']\\([^\"']+\\)" nil t)
(let ((url (match-string 1)))
(unless (gnus-html-image-url-blocked-p url blocked-images)
(unless (file-exists-p (gnus-html-image-id url))
(push url urls)
(push (gnus-html-image-id url) urls)
(push "-o" urls)))))
(let ((process
(apply 'start-process
"images" nil "curl"
"-s" "--create-dirs"
"--location"
"--max-time" "60"
urls)))
(process-kill-without-query process))))))
(provide 'gnus-html)
;;; gnus-html.el ends here
|
