1 ;;; gnus-nocem.el --- NoCeM pseudo-cancellation treatment
3 ;; Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2002, 2003, 2004,
4 ;; 2005 Free Software Foundation, Inc.
6 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
9 ;; This file is part of GNU Emacs.
11 ;; GNU Emacs is free software; you can redistribute it and/or modify
12 ;; it under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation; either version 2, or (at your option)
16 ;; GNU Emacs is distributed in the hope that it will be useful,
17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 ;; GNU General Public License for more details.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs; see the file COPYING. If not, write to the
23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
24 ;; Boston, MA 02110-1301, USA.
30 (eval-when-compile (require 'cl
))
38 (defgroup gnus-nocem nil
39 "NoCeM pseudo-cancellation treatment."
42 (defcustom gnus-nocem-groups
43 '("news.lists.filters" "news.admin.net-abuse.bulletins"
44 "alt.nocem.misc" "news.admin.net-abuse.announce")
45 "*List of groups that will be searched for NoCeM messages."
47 :type
'(repeat (string :tag
"Group")))
49 (defcustom gnus-nocem-issuers
50 '("AutoMoose-1" ; CancelMoose[tm]
51 "clewis@ferret.ocunix" ; Chris Lewis
55 "*List of NoCeM issuers to pay attention to.
57 This can also be a list of `(ISSUER CONDITION ...)' elements.
59 See <URL:http://www.xs4all.nl/~rosalind/nocemreg/nocemreg.html> for an
62 :link
'(url-link "http://www.xs4all.nl/~rosalind/nocemreg/nocemreg.html")
63 :type
'(repeat (choice string sexp
)))
65 (defcustom gnus-nocem-directory
66 (nnheader-concat gnus-article-save-directory
"NoCeM/")
67 "*Directory where NoCeM files will be stored."
71 (defcustom gnus-nocem-expiry-wait
15
72 "*Number of days to keep NoCeM headers in the cache."
76 (defcustom gnus-nocem-verifyer
'pgg-verify
77 "*Function called to verify that the NoCeM message is valid.
78 One likely value is `pgg-verify'. If the function in this variable
79 isn't bound, the message will be used unconditionally."
81 :type
'(radio (function-item pgg-verify
)
82 (function-item mc-verify
)
83 (function :tag
"other")))
85 (defcustom gnus-nocem-liberal-fetch nil
86 "*If t try to fetch all messages which have @@NCM in the subject.
87 Otherwise don't fetch messages which have references or whose message-id
88 matches a previously scanned and verified nocem message."
92 (defcustom gnus-nocem-check-article-limit
500
93 "*If non-nil, the maximum number of articles to check in any NoCeM group."
96 :type
'(choice (const :tag
"unlimited" nil
)
99 (defcustom gnus-nocem-check-from t
100 "Non-nil means check for valid issuers in message bodies.
101 Otherwise don't bother fetching articles unless their author matches a
102 valid issuer, which is much faster if you are selective about the issuers."
107 ;;; Internal variables
109 (defvar gnus-nocem-active nil
)
110 (defvar gnus-nocem-alist nil
)
111 (defvar gnus-nocem-touched-alist nil
)
112 (defvar gnus-nocem-hashtb nil
)
113 (defvar gnus-nocem-seen-message-ids nil
)
117 (defun gnus-nocem-active-file ()
118 (concat (file-name-as-directory gnus-nocem-directory
) "active"))
120 (defun gnus-nocem-cache-file ()
121 (concat (file-name-as-directory gnus-nocem-directory
) "cache"))
124 ;; faster lookups for group names:
127 (defvar gnus-nocem-real-group-hashtb nil
128 "Real-name mappings of subscribed groups.")
130 (defun gnus-fill-real-hashtb ()
131 "Fill up a hash table with the real-name mappings from the user's active file."
132 (setq gnus-nocem-real-group-hashtb
(gnus-make-hashtable
133 (length gnus-newsrc-alist
)))
134 (mapcar (lambda (group)
135 (setq group
(gnus-group-real-name (car group
)))
136 (gnus-sethash group t gnus-nocem-real-group-hashtb
))
139 (defun gnus-nocem-scan-groups ()
140 "Scan all NoCeM groups for new NoCeM messages."
142 (let ((groups gnus-nocem-groups
)
143 (gnus-inhibit-demon t
)
144 group active gactive articles check-headers
)
145 (gnus-make-directory gnus-nocem-directory
)
146 ;; Load any previous NoCeM headers.
147 (gnus-nocem-load-cache)
148 ;; Get the group name mappings:
149 (gnus-fill-real-hashtb)
150 ;; Read the active file if it hasn't been read yet.
151 (and (file-exists-p (gnus-nocem-active-file))
152 (not gnus-nocem-active
)
154 (load (gnus-nocem-active-file) t t t
)))
155 ;; Go through all groups and see whether new articles have
157 (while (setq group
(pop groups
))
158 (if (not (setq gactive
(gnus-activate-group group
)))
159 () ; This group doesn't exist.
160 (setq active
(nth 1 (assoc group gnus-nocem-active
)))
161 (when (and (not (< (cdr gactive
) (car gactive
))) ; Empty group.
163 (< (cdr active
) (cdr gactive
))))
164 ;; Ok, there are new articles in this group, se we fetch the
167 (let ((dependencies (make-vector 10 nil
))
172 (gnus-retrieve-headers
174 (gnus-uncompress-range
176 (if active
(1+ (cdr active
))
180 (gnus-get-newsgroup-headers-xover
181 articles nil dependencies
)
182 (gnus-get-newsgroup-headers dependencies
)))
183 (while (setq header
(pop headers
))
184 ;; We take a closer look on all articles that have
185 ;; "@@NCM" in the subject. Unless we already read
186 ;; this cross posted message. Nocem messages
187 ;; are not allowed to have references, so we can
188 ;; ignore scanning followups.
189 (and (string-match "@@NCM" (mail-header-subject header
))
190 (and gnus-nocem-check-from
191 (let ((case-fold-search t
))
196 (setq author
(car author
)))
198 author
(mail-header-from header
))
202 (or gnus-nocem-liberal-fetch
203 (and (or (string= "" (mail-header-references
205 (null (mail-header-references header
)))
206 (not (member (mail-header-message-id header
)
207 gnus-nocem-seen-message-ids
))))
208 (push header check-headers
)))
211 (last check-headers gnus-nocem-check-article-limit
))
212 (len (length check-headers
)))
213 (dolist (h check-headers
)
215 7 "Checking article %d in %s for NoCeM (%d of %d)..."
216 (mail-header-number h
) group
(incf i
) len
)
217 (gnus-nocem-check-article group h
)))))))
218 (setq gnus-nocem-active
219 (cons (list group gactive
)
220 (delq (assoc group gnus-nocem-active
)
221 gnus-nocem-active
)))))
222 ;; Save the results, if any.
223 (gnus-nocem-save-cache)
224 (gnus-nocem-save-active)))
226 (defun gnus-nocem-check-article (group header
)
227 "Check whether the current article is an NCM article and that we want it."
229 (let ((date (mail-header-date header
))
230 (gnus-newsgroup-name group
)
234 (time-since (date-to-time date
))
235 (days-to-time gnus-nocem-expiry-wait
)))
236 (gnus-request-article-this-buffer (mail-header-number header
) group
)
237 (goto-char (point-min))
238 (when (re-search-forward "-----BEGIN PGP MESSAGE-----" nil t
)
239 (delete-region (point-min) (match-beginning 0)))
240 (when (re-search-forward "-----END PGP MESSAGE-----\n?" nil t
)
241 (delete-region (match-end 0) (point-max)))
242 (goto-char (point-min))
243 ;; The article has to have proper NoCeM headers.
244 (when (and (setq b
(search-forward "\n@@BEGIN NCM HEADERS\n" nil t
))
245 (setq e
(search-forward "\n@@BEGIN NCM BODY\n" nil t
)))
246 ;; We get the name of the issuer.
247 (narrow-to-region b e
)
248 (setq issuer
(mail-fetch-field "issuer")
249 type
(mail-fetch-field "type"))
251 (if (not (gnus-nocem-message-wanted-p issuer type
))
252 (message "invalid NoCeM issuer: %s" issuer
)
253 (and (gnus-nocem-verify-issuer issuer
) ; She is who she says she is.
254 (gnus-nocem-enter-article) ; We gobble the message.
255 (push (mail-header-message-id header
) ; But don't come back for
256 gnus-nocem-seen-message-ids
))))))) ; second helpings.
258 (defun gnus-nocem-message-wanted-p (issuer type
)
259 (let ((issuers gnus-nocem-issuers
)
260 wanted conditions condition
)
262 ;; Do the quick check first.
263 ((member issuer issuers
)
265 ((setq conditions
(cdr (assoc issuer issuers
)))
266 ;; Check whether we want this type.
267 (while (setq condition
(pop conditions
))
270 (when (string-match condition type
)
272 ((and (consp condition
)
273 (eq (car condition
) 'not
)
274 (stringp (cadr condition
)))
275 (when (string-match (cadr condition
) type
)
278 (error "Invalid NoCeM condition: %S" condition
))))
281 (defun gnus-nocem-verify-issuer (person)
282 "Verify using PGP that the canceler is who she says she is."
283 (if (functionp gnus-nocem-verifyer
)
285 (funcall gnus-nocem-verifyer
))
286 ;; If we don't have Mailcrypt, then we use the message anyway.
289 (defun gnus-nocem-enter-article ()
290 "Enter the current article into the NoCeM cache."
291 (goto-char (point-min))
292 (let ((b (search-forward "\n@@BEGIN NCM BODY\n" nil t
))
293 (e (search-forward "\n@@END NCM BODY\n" nil t
))
294 (buf (current-buffer))
297 (narrow-to-region b
(1+ (match-beginning 0)))
298 (goto-char (point-min))
299 (while (search-forward "\t" nil t
)
302 (setq group
(let ((obarray gnus-nocem-real-group-hashtb
))
306 ((not (symbolp group
))
307 ;; Ignore invalid entries.
309 ((not (boundp group
))
310 ;; Make sure all entries in the hashtb are bound.
313 (when (gnus-gethash (gnus-group-real-name (symbol-name group
))
314 gnus-nocem-real-group-hashtb
)
317 (while (eq (char-after) ?
\t)
319 (setq id
(buffer-substring (point) (1- (search-forward "\t"))))
320 (unless (if gnus-nocem-hashtb
321 (gnus-gethash id gnus-nocem-hashtb
)
322 (setq gnus-nocem-hashtb
(gnus-make-hashtable))
324 ;; only store if not already present
325 (gnus-sethash id t gnus-nocem-hashtb
)
328 (while (eq (char-after) ?
\t)
329 (forward-line 1))))))
331 (setq gnus-nocem-touched-alist t
)
332 (push (cons (let ((time (current-time))) (setcdr (cdr time
) nil
) time
)
337 (defun gnus-nocem-load-cache ()
338 "Load the NoCeM cache."
340 (unless gnus-nocem-alist
341 ;; The buffer doesn't exist, so we create it and load the NoCeM
343 (when (file-exists-p (gnus-nocem-cache-file))
344 (load (gnus-nocem-cache-file) t t t
)
345 (gnus-nocem-alist-to-hashtb))))
347 (defun gnus-nocem-save-cache ()
348 "Save the NoCeM cache."
349 (when (and gnus-nocem-alist
350 gnus-nocem-touched-alist
)
351 (with-temp-file (gnus-nocem-cache-file)
352 (gnus-prin1 `(setq gnus-nocem-alist
',gnus-nocem-alist
)))
353 (setq gnus-nocem-touched-alist nil
)))
355 (defun gnus-nocem-save-active ()
356 "Save the NoCeM active file."
357 (with-temp-file (gnus-nocem-active-file)
358 (gnus-prin1 `(setq gnus-nocem-active
',gnus-nocem-active
))))
360 (defun gnus-nocem-alist-to-hashtb ()
361 "Create a hashtable from the Message-IDs we have."
362 (let* ((alist gnus-nocem-alist
)
363 (pprev (cons nil alist
))
365 (expiry (days-to-time gnus-nocem-expiry-wait
))
367 (setq gnus-nocem-hashtb
(gnus-make-hashtable (* (length alist
) 51)))
368 (while (setq entry
(car alist
))
369 (if (not (time-less-p (time-since (car entry
)) expiry
))
370 ;; This entry has expired, so we remove it.
371 (setcdr prev
(cdr alist
))
373 ;; This is ok, so we enter it into the hashtable.
374 (setq entry
(cdr entry
))
376 (gnus-sethash (car entry
) t gnus-nocem-hashtb
)
377 (setq entry
(cdr entry
))))
378 (setq alist
(cdr alist
)))))
380 (gnus-add-shutdown 'gnus-nocem-close
'gnus
)
382 (defun gnus-nocem-close ()
383 "Clear internal NoCeM variables."
384 (setq gnus-nocem-alist nil
385 gnus-nocem-hashtb nil
386 gnus-nocem-active nil
387 gnus-nocem-touched-alist nil
388 gnus-nocem-seen-message-ids nil
389 gnus-nocem-real-group-hashtb nil
))
391 (defun gnus-nocem-unwanted-article-p (id)
392 "Say whether article ID in the current group is wanted."
393 (and gnus-nocem-hashtb
394 (gnus-gethash id gnus-nocem-hashtb
)))
396 (provide 'gnus-nocem
)
398 ;;; arch-tag: 0e0c74ea-2f8e-4f3e-8fff-09f767c1adef
399 ;;; gnus-nocem.el ends here