1 ;;; gnus-int.el --- backend interface functions for Gnus
2 ;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
3 ;; Free Software Foundation, Inc.
5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
8 ;; This file is part of GNU Emacs.
10 ;; GNU Emacs is free software; you can redistribute it and/or modify
11 ;; it under the terms of the GNU General Public License as published by
12 ;; the Free Software Foundation; either version 2, or (at your option)
15 ;; GNU Emacs is distributed in the hope that it will be useful,
16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 ;; GNU General Public License for more details.
20 ;; You should have received a copy of the GNU General Public License
21 ;; along with GNU Emacs; see the file COPYING. If not, write to the
22 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23 ;; Boston, MA 02111-1307, USA.
29 (eval-when-compile (require 'cl))
36 (defun gnus-agent-expire (a b c)))
38 (defcustom gnus-open-server-hook nil
39 "Hook called just before opening connection to the news server."
43 (defcustom gnus-server-unopen-status nil
44 "The default status if the server is not able to open.
45 If the server is covered by Gnus agent, the possible values are
46 `denied', set the server denied; `offline', set the server offline;
47 nil, ask user. If the server is not covered by Gnus agent, set the
50 :type '(choice (const :tag "Ask" nil)
51 (const :tag "Deny server" denied)
52 (const :tag "Unplug Agent" offline)))
54 (defvar gnus-internal-registry-spool-current-method nil
55 "The current method, for the registry.")
58 ;;; Server Communication
61 (defun gnus-start-news-server (&optional confirm)
62 "Open a method for getting news.
63 If CONFIRM is non-nil, the user will be asked for an NNTP server."
65 (if gnus-current-select-method
66 ;; Stream is already opened.
69 (unless gnus-nntp-service
70 (setq gnus-nntp-server nil))
72 ;; Read server name with completion.
73 (setq gnus-nntp-server
74 (completing-read "NNTP server: "
75 (mapcar (lambda (server) (list server))
76 (cons (list gnus-nntp-server)
77 gnus-secondary-servers))
78 nil nil gnus-nntp-server)))
80 (when (and gnus-nntp-server
81 (stringp gnus-nntp-server)
82 (not (string= gnus-nntp-server "")))
83 (setq gnus-select-method
84 (cond ((or (string= gnus-nntp-server "")
85 (string= gnus-nntp-server "::"))
86 (list 'nnspool (system-name)))
87 ((string-match "^:" gnus-nntp-server)
88 (list 'nnmh gnus-nntp-server
90 (file-name-as-directory
92 (substring gnus-nntp-server 1) "~/")))
93 (list 'nnmh-get-new-mail nil)))
95 (list 'nntp gnus-nntp-server)))))
97 (setq how (car gnus-select-method))
101 (gnus-message 5 "Looking up local news spool..."))
104 (gnus-message 5 "Looking up mh spool..."))
107 (setq gnus-current-select-method gnus-select-method)
108 (gnus-run-hooks 'gnus-open-server-hook)
110 ;; gnus-open-server-hook might have opened it
111 (gnus-server-opened gnus-select-method)
112 (gnus-open-server gnus-select-method)
116 "%s (%s) open error: '%s'. Continue? "
117 (car gnus-select-method) (cadr gnus-select-method)
118 (gnus-status-message gnus-select-method)))
119 (gnus-error 1 "Couldn't open server on %s"
120 (nth 1 gnus-select-method))))))
122 (defun gnus-check-group (group)
123 "Try to make sure that the server where GROUP exists is alive."
124 (let ((method (gnus-find-method-for-group group)))
125 (or (gnus-server-opened method)
126 (gnus-open-server method))))
128 (defun gnus-check-server (&optional method silent)
129 "Check whether the connection to METHOD is down.
130 If METHOD is nil, use `gnus-select-method'.
131 If it is down, start it up (again)."
132 (let ((method (or method gnus-select-method))
134 ;; Transform virtual server names into select methods.
135 (when (stringp method)
136 (setq method (gnus-server-to-method method)))
137 (if (gnus-server-opened method)
138 ;; The stream is already opened.
142 (gnus-message 5 "Opening %s server%s..." (car method)
143 (if (equal (nth 1 method) "") ""
144 (format " on %s" (nth 1 method)))))
145 (gnus-run-hooks 'gnus-open-server-hook)
148 (setq result (gnus-open-server method))
149 (quit (message "Quit gnus-check-server")
152 (gnus-message 5 "Opening %s server%s...%s" (car method)
153 (if (equal (nth 1 method) "") ""
154 (format " on %s" (nth 1 method)))
155 (if result "done" "failed")))))))
157 (defun gnus-get-function (method function &optional noerror)
158 "Return a function symbol based on METHOD and FUNCTION."
159 ;; Translate server names into methods.
161 (error "Attempted use of a nil select method"))
162 (when (stringp method)
163 (setq method (gnus-server-to-method method)))
164 ;; Check cache of constructed names.
165 (let* ((method-sym (if gnus-agent
166 (gnus-agent-get-function method)
168 (method-fns (get method-sym 'gnus-method-functions))
169 (func (let ((method-fnlist-elt (assq function method-fns)))
170 (unless method-fnlist-elt
171 (setq method-fnlist-elt
173 (intern (format "%s-%s" method-sym function))))
174 (put method-sym 'gnus-method-functions
175 (cons method-fnlist-elt method-fns)))
176 (cdr method-fnlist-elt))))
177 ;; Maybe complain if there is no function.
178 (unless (fboundp func)
180 (error "Trying to require a method that doesn't exist"))
181 (require (car method))
182 (when (not (fboundp func))
185 (error "No such function: %s" func))))
190 ;;; Interface functions to the backends.
193 (defun gnus-open-server (gnus-command-method)
194 "Open a connection to GNUS-COMMAND-METHOD."
195 (when (stringp gnus-command-method)
196 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
197 (let ((elem (assoc gnus-command-method gnus-opened-servers)))
198 ;; If this method was previously denied, we just return nil.
199 (if (eq (nth 1 elem) 'denied)
201 (gnus-message 1 "Denied server")
206 (funcall (gnus-get-function gnus-command-method 'open-server)
207 (nth 1 gnus-command-method)
208 (nthcdr 2 gnus-command-method))
210 (gnus-message 1 (format
211 "Unable to open server due to: %s"
212 (error-message-string err)))
215 (gnus-message 1 "Quit trying to open server")
217 ;; If this hasn't been opened before, we add it to the list.
219 (setq elem (list gnus-command-method nil)
220 gnus-opened-servers (cons elem gnus-opened-servers)))
221 ;; Set the status of this server.
224 (if (eq (cadr elem) 'offline)
228 (not (eq (cadr elem) 'offline))
229 (gnus-agent-method-p gnus-command-method))
230 (or gnus-server-unopen-status
232 (format "Unable to open %s:%s, go offline? "
233 (car gnus-command-method)
234 (cadr gnus-command-method)))
238 ;; Return the result from the "open" call.
239 (cond ((eq (cadr elem) 'offline)
240 ;; I'm avoiding infinite recursion by binding unopen
241 ;; status to denied (The logic of this routine
242 ;; guarantees that I can't get to this point with
243 ;; unopen status already bound to denied).
244 (unless (eq gnus-server-unopen-status 'denied)
245 (let ((gnus-server-unopen-status 'denied))
246 (gnus-open-server gnus-command-method)))
251 (defun gnus-close-server (gnus-command-method)
252 "Close the connection to GNUS-COMMAND-METHOD."
253 (when (stringp gnus-command-method)
254 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
255 (funcall (gnus-get-function gnus-command-method 'close-server)
256 (nth 1 gnus-command-method)))
258 (defun gnus-request-list (gnus-command-method)
259 "Request the active file from GNUS-COMMAND-METHOD."
260 (when (stringp gnus-command-method)
261 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
262 (funcall (gnus-get-function gnus-command-method 'request-list)
263 (nth 1 gnus-command-method)))
265 (defun gnus-request-list-newsgroups (gnus-command-method)
266 "Request the newsgroups file from GNUS-COMMAND-METHOD."
267 (when (stringp gnus-command-method)
268 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
269 (funcall (gnus-get-function gnus-command-method 'request-list-newsgroups)
270 (nth 1 gnus-command-method)))
272 (defun gnus-request-newgroups (date gnus-command-method)
273 "Request all new groups since DATE from GNUS-COMMAND-METHOD."
274 (when (stringp gnus-command-method)
275 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
276 (let ((func (gnus-get-function gnus-command-method 'request-newgroups t)))
278 (funcall func date (nth 1 gnus-command-method)))))
280 (defun gnus-server-opened (gnus-command-method)
281 "Check whether a connection to GNUS-COMMAND-METHOD has been opened."
282 (unless (eq (gnus-server-status gnus-command-method)
284 (when (stringp gnus-command-method)
285 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
286 (funcall (inline (gnus-get-function gnus-command-method 'server-opened))
287 (nth 1 gnus-command-method))))
289 (defun gnus-status-message (gnus-command-method)
290 "Return the status message from GNUS-COMMAND-METHOD.
291 If GNUS-COMMAND-METHOD is a string, it is interpreted as a group name. The method
292 this group uses will be queried."
293 (let ((gnus-command-method
294 (if (stringp gnus-command-method)
295 (gnus-find-method-for-group gnus-command-method)
296 gnus-command-method)))
297 (funcall (gnus-get-function gnus-command-method 'status-message)
298 (nth 1 gnus-command-method))))
300 (defun gnus-request-regenerate (gnus-command-method)
301 "Request a data generation from GNUS-COMMAND-METHOD."
302 (when (stringp gnus-command-method)
303 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
304 (funcall (gnus-get-function gnus-command-method 'request-regenerate)
305 (nth 1 gnus-command-method)))
307 (defun gnus-request-group (group &optional dont-check gnus-command-method)
308 "Request GROUP. If DONT-CHECK, no information is required."
309 (let ((gnus-command-method
310 (or gnus-command-method (inline (gnus-find-method-for-group group)))))
311 (when (stringp gnus-command-method)
312 (setq gnus-command-method
313 (inline (gnus-server-to-method gnus-command-method))))
314 (funcall (inline (gnus-get-function gnus-command-method 'request-group))
315 (gnus-group-real-name group) (nth 1 gnus-command-method)
318 (defun gnus-list-active-group (group)
319 "Request active information on GROUP."
320 (let ((gnus-command-method (gnus-find-method-for-group group))
321 (func 'list-active-group))
322 (when (gnus-check-backend-function func group)
323 (funcall (gnus-get-function gnus-command-method func)
324 (gnus-group-real-name group) (nth 1 gnus-command-method)))))
326 (defun gnus-request-group-description (group)
327 "Request a description of GROUP."
328 (let ((gnus-command-method (gnus-find-method-for-group group))
329 (func 'request-group-description))
330 (when (gnus-check-backend-function func group)
331 (funcall (gnus-get-function gnus-command-method func)
332 (gnus-group-real-name group) (nth 1 gnus-command-method)))))
334 (defun gnus-request-group-articles (group)
335 "Request a list of existing articles in GROUP."
336 (let ((gnus-command-method (gnus-find-method-for-group group))
337 (func 'request-group-articles))
338 (when (gnus-check-backend-function func group)
339 (funcall (gnus-get-function gnus-command-method func)
340 (gnus-group-real-name group) (nth 1 gnus-command-method)))))
342 (defun gnus-close-group (group)
343 "Request the GROUP be closed."
344 (let ((gnus-command-method (inline (gnus-find-method-for-group group))))
345 (funcall (gnus-get-function gnus-command-method 'close-group)
346 (gnus-group-real-name group) (nth 1 gnus-command-method))))
348 (defun gnus-retrieve-headers (articles group &optional fetch-old)
349 "Request headers for ARTICLES in GROUP.
350 If FETCH-OLD, retrieve all headers (or some subset thereof) in the group."
351 (let ((gnus-command-method (gnus-find-method-for-group group)))
353 ((and gnus-use-cache (numberp (car articles)))
354 (gnus-cache-retrieve-headers articles group fetch-old))
355 ((and gnus-agent (gnus-online gnus-command-method)
356 (gnus-agent-method-p gnus-command-method))
357 (gnus-agent-retrieve-headers articles group fetch-old))
359 (funcall (gnus-get-function gnus-command-method 'retrieve-headers)
360 articles (gnus-group-real-name group)
361 (nth 1 gnus-command-method) fetch-old)))))
363 (defun gnus-retrieve-articles (articles group)
364 "Request ARTICLES in GROUP."
365 (let ((gnus-command-method (gnus-find-method-for-group group)))
366 (funcall (gnus-get-function gnus-command-method 'retrieve-articles)
367 articles (gnus-group-real-name group)
368 (nth 1 gnus-command-method))))
370 (defun gnus-retrieve-groups (groups gnus-command-method)
371 "Request active information on GROUPS from GNUS-COMMAND-METHOD."
372 (when (stringp gnus-command-method)
373 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
374 (funcall (gnus-get-function gnus-command-method 'retrieve-groups)
375 groups (nth 1 gnus-command-method)))
377 (defun gnus-request-type (group &optional article)
378 "Return the type (`post' or `mail') of GROUP (and ARTICLE)."
379 (let ((gnus-command-method (gnus-find-method-for-group group)))
380 (if (not (gnus-check-backend-function
381 'request-type (car gnus-command-method)))
383 (funcall (gnus-get-function gnus-command-method 'request-type)
384 (gnus-group-real-name group) article))))
386 (defun gnus-request-set-mark (group action)
387 "Set marks on articles in the backend."
388 (let ((gnus-command-method (gnus-find-method-for-group group)))
389 (if (not (gnus-check-backend-function
390 'request-set-mark (car gnus-command-method)))
392 (funcall (gnus-get-function gnus-command-method 'request-set-mark)
393 (gnus-group-real-name group) action
394 (nth 1 gnus-command-method)))))
396 (defun gnus-request-update-mark (group article mark)
397 "Allow the backend to change the mark the user tries to put on an article."
398 (let ((gnus-command-method (gnus-find-method-for-group group)))
399 (if (not (gnus-check-backend-function
400 'request-update-mark (car gnus-command-method)))
402 (funcall (gnus-get-function gnus-command-method 'request-update-mark)
403 (gnus-group-real-name group) article mark))))
405 (defun gnus-request-article (article group &optional buffer)
406 "Request the ARTICLE in GROUP.
407 ARTICLE can either be an article number or an article Message-ID.
408 If BUFFER, insert the article in that group."
409 (let ((gnus-command-method (gnus-find-method-for-group group)))
410 (funcall (gnus-get-function gnus-command-method 'request-article)
411 article (gnus-group-real-name group)
412 (nth 1 gnus-command-method) buffer)))
414 (defun gnus-request-head (article group)
415 "Request the head of ARTICLE in GROUP."
416 (let* ((gnus-command-method (gnus-find-method-for-group group))
417 (head (gnus-get-function gnus-command-method 'request-head t))
423 (gnus-cache-request-article article group))
424 (setq res (cons group article)
426 ;; Check the agent cache.
427 ((gnus-agent-request-article article group)
428 (setq res (cons group article)
430 ;; Use `head' function.
432 (setq res (funcall head article (gnus-group-real-name group)
433 (nth 1 gnus-command-method))))
434 ;; Use `article' function.
436 (setq res (gnus-request-article article group)
440 (set-buffer nntp-server-buffer)
441 (goto-char (point-min))
442 (when (search-forward "\n\n" nil t)
443 (delete-region (1- (point)) (point-max)))
444 (nnheader-fold-continuation-lines)))
447 (defun gnus-request-body (article group)
448 "Request the body of ARTICLE in GROUP."
449 (let* ((gnus-command-method (gnus-find-method-for-group group))
450 (head (gnus-get-function gnus-command-method 'request-body t))
456 (gnus-cache-request-article article group))
457 (setq res (cons group article)
459 ;; Check the agent cache.
460 ((gnus-agent-request-article article group)
461 (setq res (cons group article)
463 ;; Use `head' function.
465 (setq res (funcall head article (gnus-group-real-name group)
466 (nth 1 gnus-command-method))))
467 ;; Use `article' function.
469 (setq res (gnus-request-article article group)
473 (set-buffer nntp-server-buffer)
474 (goto-char (point-min))
475 (when (search-forward "\n\n" nil t)
476 (delete-region (point-min) (1- (point))))))
479 (defun gnus-request-post (gnus-command-method)
480 "Post the current buffer using GNUS-COMMAND-METHOD."
481 (when (stringp gnus-command-method)
482 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
483 (funcall (gnus-get-function gnus-command-method 'request-post)
484 (nth 1 gnus-command-method)))
486 (defun gnus-request-scan (group gnus-command-method)
487 "Request a SCAN being performed in GROUP from GNUS-COMMAND-METHOD.
488 If GROUP is nil, all groups on GNUS-COMMAND-METHOD are scanned."
489 (let ((gnus-command-method
490 (if group (gnus-find-method-for-group group) gnus-command-method))
491 (gnus-inhibit-demon t)
492 (mail-source-plugged gnus-plugged))
493 (if (or gnus-plugged (not (gnus-agent-method-p gnus-command-method)))
495 (setq gnus-internal-registry-spool-current-method gnus-command-method)
496 (funcall (gnus-get-function gnus-command-method 'request-scan)
497 (and group (gnus-group-real-name group))
498 (nth 1 gnus-command-method))))))
500 (defsubst gnus-request-update-info (info gnus-command-method)
501 "Request that GNUS-COMMAND-METHOD update INFO."
502 (when (stringp gnus-command-method)
503 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
504 (when (gnus-check-backend-function
505 'request-update-info (car gnus-command-method))
506 (let ((group (gnus-info-group info)))
507 (and (funcall (gnus-get-function gnus-command-method
508 'request-update-info)
509 (gnus-group-real-name group)
510 info (nth 1 gnus-command-method))
511 ;; If the minimum article number is greater than 1, then all
512 ;; smaller article numbers are known not to exist; we'll
513 ;; artificially add those to the 'read range.
514 (let* ((active (gnus-active group))
517 (let* ((range (if (= min 2) 1 (cons 1 (1- min))))
518 (read (gnus-info-read info))
519 (new-read (gnus-range-add read (list range))))
520 (gnus-info-set-read info new-read)))
523 (defun gnus-request-expire-articles (articles group &optional force)
524 (let* ((gnus-command-method (gnus-find-method-for-group group))
527 (gnus-get-function gnus-command-method 'request-expire-articles)
528 articles (gnus-group-real-name group) (nth 1 gnus-command-method)
530 (when (and gnus-agent
531 (gnus-agent-method-p gnus-command-method))
532 (let ((expired-articles (gnus-sorted-difference articles not-deleted)))
533 (when expired-articles
534 (gnus-agent-expire expired-articles group 'force))))
537 (defun gnus-request-move-article (article group server accept-function
539 (let* ((gnus-command-method (gnus-find-method-for-group group))
540 (result (funcall (gnus-get-function gnus-command-method
541 'request-move-article)
542 article (gnus-group-real-name group)
543 (nth 1 gnus-command-method) accept-function last)))
544 (when (and result gnus-agent
545 (gnus-agent-method-p gnus-command-method))
546 (gnus-agent-expire (list article) group 'force))
549 (defun gnus-request-accept-article (group &optional gnus-command-method last
551 ;; Make sure there's a newline at the end of the article.
552 (when (stringp gnus-command-method)
553 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
554 (when (and (not gnus-command-method)
556 (setq gnus-command-method (gnus-group-name-to-method group)))
557 (goto-char (point-max))
561 (let ((message-options message-options))
562 (message-options-set-recipient)
564 (message-narrow-to-head)
565 (let ((mail-parse-charset message-default-charset))
566 (mail-encode-encoded-word-buffer)))
567 (message-encode-message-body)))
568 (let ((gnus-command-method (or gnus-command-method
569 (gnus-find-method-for-group group))))
570 (funcall (gnus-get-function gnus-command-method 'request-accept-article)
571 (if (stringp group) (gnus-group-real-name group) group)
572 (cadr gnus-command-method)
575 (defun gnus-request-replace-article (article group buffer &optional no-encode)
577 (let ((message-options message-options))
578 (message-options-set-recipient)
580 (message-narrow-to-head)
581 (let ((mail-parse-charset message-default-charset))
582 (mail-encode-encoded-word-buffer)))
583 (message-encode-message-body)))
584 (let ((func (car (gnus-group-name-to-method group))))
585 (funcall (intern (format "%s-request-replace-article" func))
586 article (gnus-group-real-name group) buffer)))
588 (defun gnus-request-associate-buffer (group)
589 (let ((gnus-command-method (gnus-find-method-for-group group)))
590 (funcall (gnus-get-function gnus-command-method 'request-associate-buffer)
591 (gnus-group-real-name group))))
593 (defun gnus-request-restore-buffer (article group)
594 "Request a new buffer restored to the state of ARTICLE."
595 (let ((gnus-command-method (gnus-find-method-for-group group)))
596 (funcall (gnus-get-function gnus-command-method 'request-restore-buffer)
597 article (gnus-group-real-name group)
598 (nth 1 gnus-command-method))))
600 (defun gnus-request-create-group (group &optional gnus-command-method args)
601 (when (stringp gnus-command-method)
602 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
603 (let ((gnus-command-method
604 (or gnus-command-method (gnus-find-method-for-group group))))
605 (funcall (gnus-get-function gnus-command-method 'request-create-group)
606 (gnus-group-real-name group) (nth 1 gnus-command-method) args)))
608 (defun gnus-request-delete-group (group &optional force)
609 (let ((gnus-command-method (gnus-find-method-for-group group)))
610 (funcall (gnus-get-function gnus-command-method 'request-delete-group)
611 (gnus-group-real-name group) force (nth 1 gnus-command-method))))
613 (defun gnus-request-rename-group (group new-name)
614 (let ((gnus-command-method (gnus-find-method-for-group group)))
615 (funcall (gnus-get-function gnus-command-method 'request-rename-group)
616 (gnus-group-real-name group)
617 (gnus-group-real-name new-name) (nth 1 gnus-command-method))))
619 (defun gnus-close-backends ()
620 ;; Send a close request to all backends that support such a request.
621 (let ((methods gnus-valid-select-methods)
622 (gnus-inhibit-demon t)
623 func gnus-command-method)
624 (while (setq gnus-command-method (pop methods))
625 (when (fboundp (setq func (intern
626 (concat (car gnus-command-method)
630 (defun gnus-asynchronous-p (gnus-command-method)
631 (let ((func (gnus-get-function gnus-command-method 'asynchronous-p t)))
635 (defun gnus-remove-denial (gnus-command-method)
636 (when (stringp gnus-command-method)
637 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
638 (let* ((elem (assoc gnus-command-method gnus-opened-servers))
639 (status (cadr elem)))
640 ;; If this hasn't been opened before, we add it to the list.
641 (when (eq status 'denied)
642 ;; Set the status of this server.
643 (setcar (cdr elem) 'closed))))
647 ;;; gnus-int.el ends here