1 ;;; html2text.el --- a simple html to plain text converter
3 ;; Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
5 ;; Author: Joakim Hove <hove@phys.ntnu.no>
7 ;; This file is part of GNU Emacs.
9 ;; GNU Emacs is free software; you can redistribute it and/or modify
10 ;; it under the terms of the GNU General Public License as published by
11 ;; the Free Software Foundation; either version 2, or (at your option)
14 ;; GNU Emacs is distributed in the hope that it will be useful,
15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 ;; GNU General Public License for more details.
19 ;; You should have received a copy of the GNU General Public License
20 ;; along with GNU Emacs; see the file COPYING. If not, write to the
21 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
22 ;; Boston, MA 02110-1301, USA.
26 ;; These functions provide a simple way to wash/clean html infected
27 ;; mails. Definitely do not work in all cases, but some improvement
28 ;; in readability is generally obtained. Formatting is only done in
29 ;; the buffer, so the next time you enter the article it will be
32 ;; The main function is `html2text'.
43 (defvar html2text-format-single-element-list
'(("hr" . html2text-clean-hr
)))
45 (defvar html2text-replace-list
46 '((" " .
" ") (">" .
">") ("<" .
"<") (""" .
"\"")
47 ("&" .
"&") ("'" .
"'"))
48 "The map of entity to text.
50 This is an alist were each element is a dotted pair consisting of an
51 old string, and a replacement string. This replacement is done by the
52 function `html2text-substitute' which basically performs a
53 `replace-string' operation for every element in the list. This is
54 completely verbatim - without any use of REGEXP.")
56 (defvar html2text-remove-tag-list
57 '("html" "body" "p" "img" "dir" "head" "div" "br" "font" "title" "meta")
58 "A list of removable tags.
60 This is a list of tags which should be removed, without any
61 formatting. Note that tags in the list are presented *without*
62 any \"<\" or \">\". All occurrences of a tag appearing in this
63 list are removed, irrespective of whether it is a closing or
64 opening tag, or if the tag has additional attributes. The
65 deletion is done by the function `html2text-remove-tags'.
67 For instance the text:
69 \"Here comes something <font size\"+3\" face=\"Helvetica\"> big </font>.\"
73 \"Here comes something big.\"
75 If this list contains the element \"font\".")
77 (defvar html2text-format-tag-list
78 '(("b" . html2text-clean-bold
)
79 ("strong" . html2text-clean-bold
)
80 ("u" . html2text-clean-underline
)
81 ("i" . html2text-clean-italic
)
82 ("em" . html2text-clean-italic
)
83 ("blockquote" . html2text-clean-blockquote
)
84 ("a" . html2text-clean-anchor
)
85 ("ul" . html2text-clean-ul
)
86 ("ol" . html2text-clean-ol
)
87 ("dl" . html2text-clean-dl
)
88 ("center" . html2text-clean-center
))
89 "An alist of tags and processing functions.
91 This is an alist where each dotted pair consists of a tag, and then
92 the name of a function to be called when this tag is found. The
93 function is called with the arguments p1, p2, p3 and p4. These are
96 \"<b> This is bold text </b>\"
101 Then the called function will typically format the text somewhat and
104 (defvar html2text-remove-tag-list2
'("li" "dt" "dd" "meta")
105 "Another list of removable tags.
107 This is a list of tags which are removed similarly to the list
108 `html2text-remove-tag-list' - but these tags are retained for the
109 formatting, and then moved afterward.")
112 ;; </Global variables>
115 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
116 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
119 ;; <Utility functions>
123 (defun html2text-replace-string (from-string to-string min max
)
124 "Replace FROM-STRING with TO-STRING in region from MIN to MAX."
126 (let ((delta (- (string-width to-string
) (string-width from-string
)))
128 (while (search-forward from-string max t
)
129 (replace-match to-string
)
130 (setq change
(+ change delta
)))
134 ;; </Utility functions>
137 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
138 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
141 ;; <Functions related to attributes> i.e. <font size=+3>
144 (defun html2text-attr-value (list attribute
)
145 "Get value of ATTRIBUTE from LIST."
146 (nth 1 (assoc attribute list
)))
148 (defun html2text-get-attr (p1 p2
)
150 (re-search-forward " +[^ ]" p2 t
)
151 (let* ((attr-string (buffer-substring-no-properties (1- (point)) (1- p2
)))
152 (tmp-list (split-string attr-string
))
155 (prev (car tmp-list
))
156 (this (nth 1 tmp-list
))
157 (next (nth 2 tmp-list
))
162 ((string-match "[^ ]=[^ ]" prev
)
163 (let ((attr (nth 0 (split-string prev
"=")))
164 (value (nth 1 (split-string prev
"="))))
165 (setq attr-list
(cons (list attr value
) attr-list
))))
167 ((string-match "[^ ]=\\'" prev
)
168 (setq attr-list
(cons (list (substring prev
0 -
1) this
) attr-list
))))
170 (while (< index
(length tmp-list
))
173 ((string-match "[^ ]=[^ ]" this
)
174 (let ((attr (nth 0 (split-string this
"=")))
175 (value (nth 1 (split-string this
"="))))
176 (setq attr-list
(cons (list attr value
) attr-list
))))
178 ((string-match "\\`=[^ ]" this
)
179 (setq attr-list
(cons (list prev
(substring this
1)) attr-list
)))
181 ((string-match "[^ ]=\\'" this
)
182 (setq attr-list
(cons (list (substring this
0 -
1) next
) attr-list
)))
185 (setq attr-list
(cons (list prev next
) attr-list
))))
186 (setq index
(1+ index
))
189 (setq next
(nth (1+ index
) tmp-list
)))
191 ;; Tags with no accompanying "=" i.e. value=nil
193 (setq prev
(car tmp-list
))
194 (setq this
(nth 1 tmp-list
))
195 (setq next
(nth 2 tmp-list
))
198 (when (and (not (string-match "=" prev
))
199 (not (string= (substring this
0 1) "=")))
200 (setq attr-list
(cons (list prev nil
) attr-list
)))
201 (while (< index
(1- (length tmp-list
)))
202 (when (and (not (string-match "=" this
))
203 (not (or (string= (substring next
0 1) "=")
204 (string= (substring prev -
1) "="))))
205 (setq attr-list
(cons (list this nil
) attr-list
)))
206 (setq index
(1+ index
))
209 (setq next
(nth (1+ index
) tmp-list
)))
212 (not (string-match "=" this
))
213 (not (string= (substring prev -
1) "=")))
214 (setq attr-list
(cons (list this nil
) attr-list
)))
219 ;; </Functions related to attributes>
222 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
223 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
226 ;; <Functions to be called to format a tag-pair>
228 (defun html2text-clean-list-items (p1 p2 list-type
)
232 (while (re-search-forward "<li>" p2 t
)
233 (setq items
(1+ items
)))
235 (while (< item-nr items
)
236 (setq item-nr
(1+ item-nr
))
237 (re-search-forward "<li>" (point-max) t
)
239 ((string= list-type
"ul") (insert " o "))
240 ((string= list-type
"ol") (insert (format " %s: " item-nr
)))
241 (t (insert " x "))))))
243 (defun html2text-clean-dtdd (p1 p2
)
247 (while (re-search-forward "<dt>" p2 t
)
248 (setq items
(1+ items
)))
250 (while (< item-nr items
)
251 (setq item-nr
(1+ item-nr
))
252 (re-search-forward "<dt>\\([ ]*\\)" (point-max) t
)
253 (when (match-string 1)
254 (delete-region (point) (- (point) (string-width (match-string 1)))))
255 (let ((def-p1 (point))
257 (re-search-forward "\\([ ]*\\)\\(</dt>\\|<dd>\\)" (point-max) t
)
260 (let* ((mw1 (string-width (match-string 1)))
261 (mw2 (string-width (match-string 2)))
263 (goto-char (- (point) mw
))
264 (delete-region (point) (+ (point) mw1
))
265 (setq def-p2
(point))))
266 (setq def-p2
(- (point) (string-width (match-string 2)))))
267 (put-text-property def-p1 def-p2
'face
'bold
)))))
269 (defun html2text-delete-tags (p1 p2 p3 p4
)
270 (delete-region p1 p2
)
271 (delete-region (- p3
(- p2 p1
)) (- p4
(- p2 p1
))))
273 (defun html2text-delete-single-tag (p1 p2
)
274 (delete-region p1 p2
))
276 (defun html2text-clean-hr (p1 p2
)
277 (html2text-delete-single-tag p1 p2
)
280 (insert (make-string fill-column ?-
)))
282 (defun html2text-clean-ul (p1 p2 p3 p4
)
283 (html2text-delete-tags p1 p2 p3 p4
)
284 (html2text-clean-list-items p1
(- p3
(- p1 p2
)) "ul"))
286 (defun html2text-clean-ol (p1 p2 p3 p4
)
287 (html2text-delete-tags p1 p2 p3 p4
)
288 (html2text-clean-list-items p1
(- p3
(- p1 p2
)) "ol"))
290 (defun html2text-clean-dl (p1 p2 p3 p4
)
291 (html2text-delete-tags p1 p2 p3 p4
)
292 (html2text-clean-dtdd p1
(- p3
(- p1 p2
))))
294 (defun html2text-clean-center (p1 p2 p3 p4
)
295 (html2text-delete-tags p1 p2 p3 p4
)
296 (center-region p1
(- p3
(- p2 p1
))))
298 (defun html2text-clean-bold (p1 p2 p3 p4
)
299 (put-text-property p2 p3
'face
'bold
)
300 (html2text-delete-tags p1 p2 p3 p4
))
302 (defun html2text-clean-title (p1 p2 p3 p4
)
303 (put-text-property p2 p3
'face
'bold
)
304 (html2text-delete-tags p1 p2 p3 p4
))
306 (defun html2text-clean-underline (p1 p2 p3 p4
)
307 (put-text-property p2 p3
'face
'underline
)
308 (html2text-delete-tags p1 p2 p3 p4
))
310 (defun html2text-clean-italic (p1 p2 p3 p4
)
311 (put-text-property p2 p3
'face
'italic
)
312 (html2text-delete-tags p1 p2 p3 p4
))
314 (defun html2text-clean-font (p1 p2 p3 p4
)
315 (html2text-delete-tags p1 p2 p3 p4
))
317 (defun html2text-clean-blockquote (p1 p2 p3 p4
)
318 (html2text-delete-tags p1 p2 p3 p4
))
320 (defun html2text-clean-anchor (p1 p2 p3 p4
)
321 ;; If someone can explain how to make the URL clickable I will surely
322 ;; improve upon this.
323 ;; Maybe `goto-addr.el' can be used here.
324 (let* ((attr-list (html2text-get-attr p1 p2
))
325 (href (html2text-attr-value attr-list
"href")))
326 (delete-region p1 p4
)
329 (insert (substring href
1 -
1 ))
330 (put-text-property p1
(point) 'face
'bold
))))
333 ;; </Functions to be called to format a tag-pair>
336 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
337 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
340 ;; <Functions to be called to fix up paragraphs>
343 (defun html2text-fix-paragraph (p1 p2
)
348 (when (re-search-forward "<br>$" p2 t
)
350 (when (re-search-forward ".+[^<][^b][^r][^>]$" p2 t
)
352 (setq refill-start
(point))
354 (re-search-backward ".+[^<][^b][^r][^>]$" refill-start t
)
357 ;; refill-stop should ideally be adjusted to
358 ;; accomodate the "<br>" strings which are removed
359 ;; between refill-start and refill-stop. Can simply
360 ;; be returned from my-replace-string
361 (setq refill-stop
(+ (point)
362 (html2text-replace-string
364 refill-start
(point))))
365 ;; (message "Point = %s refill-stop = %s" (point) refill-stop)
367 (fill-region refill-start refill-stop
))))
368 (html2text-replace-string "<br>" "" p1 p2
))
371 ;; This one is interactive ...
373 (defun html2text-fix-paragraphs ()
374 "This _tries_ to fix up the paragraphs - this is done in quite a ad-hook
375 fashion, quite close to pure guess-work. It does work in some cases though."
377 (goto-char (point-min))
378 (while (re-search-forward "^<br>$" nil t
)
379 (delete-region (match-beginning 0) (match-end 0)))
380 ;; Removing lonely <br> on a single line, if they are left intact we
381 ;; dont have any paragraphs at all.
382 (goto-char (point-min))
385 (forward-paragraph 1)
386 ;;(message "Kaller fix med p1=%s p2=%s " p1 (1- (point))) (sleep-for 5)
387 (html2text-fix-paragraph p1
(1- (point)))
390 (forward-paragraph 1)))))
393 ;; </Functions to be called to fix up paragraphs>
396 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
397 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
400 ;; <Interactive functions>
403 (defun html2text-remove-tags (tag-list)
404 "Removes the tags listed in the list `html2text-remove-tag-list'.
405 See the documentation for that variable."
407 (dolist (tag tag-list
)
408 (goto-char (point-min))
409 (while (re-search-forward (format "\\(</?%s[^>]*>\\)" tag
) (point-max) t
)
410 (delete-region (match-beginning 0) (match-end 0)))))
412 (defun html2text-format-tags ()
413 "See the variable `html2text-format-tag-list' for documentation."
415 (dolist (tag-and-function html2text-format-tag-list
)
416 (let ((tag (car tag-and-function
))
417 (function (cdr tag-and-function
)))
418 (goto-char (point-min))
419 (while (re-search-forward (format "\\(<%s\\( [^>]*\\)?>\\)" tag
)
424 (search-backward "<" (point-min) t
)
426 (unless (search-forward (format "</%s>" tag
) (point-max) t
)
428 (insert (format "</%s>" tag
)))
430 (search-backward "</" (point-min) t
)
432 (funcall function p1 p2 p3 p4
)
435 (defun html2text-substitute ()
436 "See the variable `html2text-replace-list' for documentation."
438 (dolist (e html2text-replace-list
)
439 (goto-char (point-min))
440 (let ((old-string (car e
))
441 (new-string (cdr e
)))
442 (html2text-replace-string old-string new-string
(point-min) (point-max)))))
444 (defun html2text-format-single-elements ()
446 (dolist (tag-and-function html2text-format-single-element-list
)
447 (let ((tag (car tag-and-function
))
448 (function (cdr tag-and-function
)))
449 (goto-char (point-min))
450 (while (re-search-forward (format "\\(<%s\\( [^>]*\\)?>\\)" tag
)
454 (search-backward "<" (point-min) t
)
456 (funcall function p1 p2
))))))
464 "Convert HTML to plain text in the current buffer."
467 (let ((case-fold-search t
)
469 (html2text-remove-tags html2text-remove-tag-list
)
470 (html2text-format-tags)
471 (html2text-remove-tags html2text-remove-tag-list2
)
472 (html2text-substitute)
473 (html2text-format-single-elements)
474 (html2text-fix-paragraphs))))
477 ;; </Interactive functions>
480 ;;; arch-tag: e9e57b79-35d4-4de1-a647-e7e01fe56d1e
481 ;;; html2text.el ends here