1 ;;; gnus-int.el --- backend interface functions for Gnus
2 ;; Copyright (C) 1996, 1997, 1998, 1999, 2000
3 ;; Free Software Foundation, Inc.
5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
6 ;; MORIOKA Tomohiko <morioka@jaist.ac.jp>
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., 59 Temple Place - Suite 330,
24 ;; Boston, MA 02111-1307, USA.
30 (eval-when-compile (require 'cl))
34 (defcustom gnus-open-server-hook nil
35 "Hook called just before opening connection to the news server."
40 ;;; Server Communication
43 (defun gnus-start-news-server (&optional confirm)
44 "Open a method for getting news.
45 If CONFIRM is non-nil, the user will be asked for an NNTP server."
47 (if gnus-current-select-method
48 ;; Stream is already opened.
51 (unless gnus-nntp-service
52 (setq gnus-nntp-server nil))
54 ;; Read server name with completion.
55 (setq gnus-nntp-server
56 (completing-read "NNTP server: "
57 (mapcar (lambda (server) (list server))
58 (cons (list gnus-nntp-server)
59 gnus-secondary-servers))
60 nil nil gnus-nntp-server)))
62 (when (and gnus-nntp-server
63 (stringp gnus-nntp-server)
64 (not (string= gnus-nntp-server "")))
65 (setq gnus-select-method
66 (cond ((or (string= gnus-nntp-server "")
67 (string= gnus-nntp-server "::"))
68 (list 'nnspool (system-name)))
69 ((string-match "^:" gnus-nntp-server)
70 (list 'nnmh gnus-nntp-server
72 (file-name-as-directory
74 (substring gnus-nntp-server 1) "~/")))
75 (list 'nnmh-get-new-mail nil)))
77 (list 'nntp gnus-nntp-server)))))
79 (setq how (car gnus-select-method))
83 (gnus-message 5 "Looking up local news spool..."))
86 (gnus-message 5 "Looking up mh spool..."))
89 (setq gnus-current-select-method gnus-select-method)
90 (gnus-run-hooks 'gnus-open-server-hook)
92 ;; gnus-open-server-hook might have opened it
93 (gnus-server-opened gnus-select-method)
94 (gnus-open-server gnus-select-method)
98 "%s (%s) open error: '%s'. Continue? "
99 (car gnus-select-method) (cadr gnus-select-method)
100 (gnus-status-message gnus-select-method)))
101 (gnus-error 1 "Couldn't open server on %s"
102 (nth 1 gnus-select-method))))))
104 (defun gnus-check-group (group)
105 "Try to make sure that the server where GROUP exists is alive."
106 (let ((method (gnus-find-method-for-group group)))
107 (or (gnus-server-opened method)
108 (gnus-open-server method))))
110 (defun gnus-check-server (&optional method silent)
111 "Check whether the connection to METHOD is down.
112 If METHOD is nil, use `gnus-select-method'.
113 If it is down, start it up (again)."
114 (let ((method (or method gnus-select-method)))
115 ;; Transform virtual server names into select methods.
116 (when (stringp method)
117 (setq method (gnus-server-to-method method)))
118 (if (gnus-server-opened method)
119 ;; The stream is already opened.
123 (gnus-message 5 "Opening %s server%s..." (car method)
124 (if (equal (nth 1 method) "") ""
125 (format " on %s" (nth 1 method)))))
126 (gnus-run-hooks 'gnus-open-server-hook)
128 (gnus-open-server method)
132 (defun gnus-get-function (method function &optional noerror)
133 "Return a function symbol based on METHOD and FUNCTION."
134 ;; Translate server names into methods.
136 (error "Attempted use of a nil select method"))
137 (when (stringp method)
138 (setq method (gnus-server-to-method method)))
139 ;; Check cache of constructed names.
140 (let* ((method-sym (if gnus-agent
141 (gnus-agent-get-function method)
143 (method-fns (get method-sym 'gnus-method-functions))
144 (func (let ((method-fnlist-elt (assq function method-fns)))
145 (unless method-fnlist-elt
146 (setq method-fnlist-elt
148 (intern (format "%s-%s" method-sym function))))
149 (put method-sym 'gnus-method-functions
150 (cons method-fnlist-elt method-fns)))
151 (cdr method-fnlist-elt))))
152 ;; Maybe complain if there is no function.
153 (unless (fboundp func)
155 (error "Trying to require a method that doesn't exist"))
156 (require (car method))
157 (when (not (fboundp func))
160 (error "No such function: %s" func))))
165 ;;; Interface functions to the backends.
168 (defun gnus-open-server (gnus-command-method)
169 "Open a connection to GNUS-COMMAND-METHOD."
170 (when (stringp gnus-command-method)
171 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
172 (let ((elem (assoc gnus-command-method gnus-opened-servers)))
173 ;; If this method was previously denied, we just return nil.
174 (if (eq (nth 1 elem) 'denied)
176 (gnus-message 1 "Denied server")
180 (funcall (gnus-get-function gnus-command-method 'open-server)
181 (nth 1 gnus-command-method)
182 (nthcdr 2 gnus-command-method))))
183 ;; If this hasn't been opened before, we add it to the list.
185 (setq elem (list gnus-command-method nil)
186 gnus-opened-servers (cons elem gnus-opened-servers)))
187 ;; Set the status of this server.
188 (setcar (cdr elem) (if result 'ok 'denied))
189 ;; Return the result from the "open" call.
192 (defun gnus-close-server (gnus-command-method)
193 "Close the connection to GNUS-COMMAND-METHOD."
194 (when (stringp gnus-command-method)
195 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
196 (funcall (gnus-get-function gnus-command-method 'close-server)
197 (nth 1 gnus-command-method)))
199 (defun gnus-request-list (gnus-command-method)
200 "Request the active file from GNUS-COMMAND-METHOD."
201 (when (stringp gnus-command-method)
202 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
203 (funcall (gnus-get-function gnus-command-method 'request-list)
204 (nth 1 gnus-command-method)))
206 (defun gnus-request-list-newsgroups (gnus-command-method)
207 "Request the newsgroups file from GNUS-COMMAND-METHOD."
208 (when (stringp gnus-command-method)
209 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
210 (funcall (gnus-get-function gnus-command-method 'request-list-newsgroups)
211 (nth 1 gnus-command-method)))
213 (defun gnus-request-newgroups (date gnus-command-method)
214 "Request all new groups since DATE from GNUS-COMMAND-METHOD."
215 (when (stringp gnus-command-method)
216 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
217 (let ((func (gnus-get-function gnus-command-method 'request-newgroups t)))
219 (funcall func date (nth 1 gnus-command-method)))))
221 (defun gnus-server-opened (gnus-command-method)
222 "Check whether a connection to GNUS-COMMAND-METHOD has been opened."
223 (unless (eq (gnus-server-status gnus-command-method)
225 (when (stringp gnus-command-method)
226 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
227 (funcall (inline (gnus-get-function gnus-command-method 'server-opened))
228 (nth 1 gnus-command-method))))
230 (defun gnus-status-message (gnus-command-method)
231 "Return the status message from GNUS-COMMAND-METHOD.
232 If GNUS-COMMAND-METHOD is a string, it is interpreted as a group name. The method
233 this group uses will be queried."
234 (let ((gnus-command-method
235 (if (stringp gnus-command-method)
236 (gnus-find-method-for-group gnus-command-method)
237 gnus-command-method)))
238 (funcall (gnus-get-function gnus-command-method 'status-message)
239 (nth 1 gnus-command-method))))
241 (defun gnus-request-regenerate (gnus-command-method)
242 "Request a data generation from GNUS-COMMAND-METHOD."
243 (when (stringp gnus-command-method)
244 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
245 (funcall (gnus-get-function gnus-command-method 'request-regenerate)
246 (nth 1 gnus-command-method)))
248 (defun gnus-request-group (group &optional dont-check gnus-command-method)
249 "Request GROUP. If DONT-CHECK, no information is required."
250 (let ((gnus-command-method
251 (or gnus-command-method (inline (gnus-find-method-for-group group)))))
252 (when (stringp gnus-command-method)
253 (setq gnus-command-method
254 (inline (gnus-server-to-method gnus-command-method))))
255 (funcall (inline (gnus-get-function gnus-command-method 'request-group))
256 (gnus-group-real-name group) (nth 1 gnus-command-method)
259 (defun gnus-list-active-group (group)
260 "Request active information on GROUP."
261 (let ((gnus-command-method (gnus-find-method-for-group group))
262 (func 'list-active-group))
263 (when (gnus-check-backend-function func group)
264 (funcall (gnus-get-function gnus-command-method func)
265 (gnus-group-real-name group) (nth 1 gnus-command-method)))))
267 (defun gnus-request-group-description (group)
268 "Request a description of GROUP."
269 (let ((gnus-command-method (gnus-find-method-for-group group))
270 (func 'request-group-description))
271 (when (gnus-check-backend-function func group)
272 (funcall (gnus-get-function gnus-command-method func)
273 (gnus-group-real-name group) (nth 1 gnus-command-method)))))
275 (defun gnus-request-group-articles (group)
276 "Request a list of existing articles in GROUP."
277 (let ((gnus-command-method (gnus-find-method-for-group group))
278 (func 'request-group-articles))
279 (when (gnus-check-backend-function func group)
280 (funcall (gnus-get-function gnus-command-method func)
281 (gnus-group-real-name group) (nth 1 gnus-command-method)))))
283 (defun gnus-close-group (group)
284 "Request the GROUP be closed."
285 (let ((gnus-command-method (inline (gnus-find-method-for-group group))))
286 (funcall (gnus-get-function gnus-command-method 'close-group)
287 (gnus-group-real-name group) (nth 1 gnus-command-method))))
289 (defun gnus-retrieve-headers (articles group &optional fetch-old)
290 "Request headers for ARTICLES in GROUP.
291 If FETCH-OLD, retrieve all headers (or some subset thereof) in the group."
292 (let ((gnus-command-method (gnus-find-method-for-group group)))
293 (if (and gnus-use-cache (numberp (car articles)))
294 (gnus-cache-retrieve-headers articles group fetch-old)
295 (funcall (gnus-get-function gnus-command-method 'retrieve-headers)
296 articles (gnus-group-real-name group)
297 (nth 1 gnus-command-method) fetch-old))))
299 (defun gnus-retrieve-parsed-headers (articles group &optional fetch-old
300 dependencies force-new)
301 "Request parsed-headers for ARTICLES in GROUP.
302 If FETCH-OLD, retrieve all headers (or some subset thereof) in the group."
306 (set-buffer gnus-summary-buffer)
307 gnus-newsgroup-dependencies)))
308 (let ((gnus-command-method (gnus-find-method-for-group group))
310 (if (and gnus-use-cache (numberp (car articles)))
312 (gnus-cache-retrieve-parsed-headers articles group fetch-old
313 dependencies force-new))
314 (let ((func (gnus-get-function gnus-command-method
315 'retrieve-parsed-headers 'no-error)))
317 (setq headers (funcall func articles dependencies
318 (gnus-group-real-name group)
319 (nth 1 gnus-command-method) fetch-old
321 gnus-headers-retrieved-by (car headers)
322 headers (cdr headers))
323 (setq gnus-headers-retrieved-by
325 (gnus-get-function gnus-command-method 'retrieve-headers)
326 articles (gnus-group-real-name group)
327 (nth 1 gnus-command-method) fetch-old))
330 (if (eq gnus-headers-retrieved-by 'nov)
331 (gnus-get-newsgroup-headers-xover
332 articles nil dependencies gnus-newsgroup-name t)
333 (gnus-get-newsgroup-headers dependencies)))
336 (defun gnus-retrieve-articles (articles group)
337 "Request ARTICLES in GROUP."
338 (let ((gnus-command-method (gnus-find-method-for-group group)))
339 (funcall (gnus-get-function gnus-command-method 'retrieve-articles)
340 articles (gnus-group-real-name group)
341 (nth 1 gnus-command-method))))
343 (defun gnus-retrieve-groups (groups gnus-command-method)
344 "Request active information on GROUPS from GNUS-COMMAND-METHOD."
345 (when (stringp gnus-command-method)
346 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
347 (funcall (gnus-get-function gnus-command-method 'retrieve-groups)
348 groups (nth 1 gnus-command-method)))
350 (defun gnus-request-type (group &optional article)
351 "Return the type (`post' or `mail') of GROUP (and ARTICLE)."
352 (let ((gnus-command-method (gnus-find-method-for-group group)))
353 (if (not (gnus-check-backend-function
354 'request-type (car gnus-command-method)))
356 (funcall (gnus-get-function gnus-command-method 'request-type)
357 (gnus-group-real-name group) article))))
359 (defun gnus-request-set-mark (group action)
360 "Set marks on articles in the backend."
361 (let ((gnus-command-method (gnus-find-method-for-group group)))
362 (if (not (gnus-check-backend-function
363 'request-set-mark (car gnus-command-method)))
365 (funcall (gnus-get-function gnus-command-method 'request-set-mark)
366 (gnus-group-real-name group) action
367 (nth 1 gnus-command-method)))))
369 (defun gnus-request-update-mark (group article mark)
370 "Allow the backend to change the mark the user tries to put on an article."
371 (let ((gnus-command-method (gnus-find-method-for-group group)))
372 (if (not (gnus-check-backend-function
373 'request-update-mark (car gnus-command-method)))
375 (funcall (gnus-get-function gnus-command-method 'request-update-mark)
376 (gnus-group-real-name group) article mark))))
378 (defun gnus-request-article (article group &optional buffer)
379 "Request the ARTICLE in GROUP.
380 ARTICLE can either be an article number or an article Message-ID.
381 If BUFFER, insert the article in that group."
382 (let ((gnus-command-method (gnus-find-method-for-group group)))
383 (funcall (gnus-get-function gnus-command-method 'request-article)
384 article (gnus-group-real-name group)
385 (nth 1 gnus-command-method) buffer)))
387 (defun gnus-request-head (article group)
388 "Request the head of ARTICLE in GROUP."
389 (let* ((gnus-command-method (gnus-find-method-for-group group))
390 (head (gnus-get-function gnus-command-method 'request-head t))
396 (gnus-cache-request-article article group))
397 (setq res (cons group article)
399 ;; Use `head' function.
401 (setq res (funcall head article (gnus-group-real-name group)
402 (nth 1 gnus-command-method))))
403 ;; Use `article' function.
405 (setq res (gnus-request-article article group)
409 (set-buffer nntp-server-buffer)
410 (goto-char (point-min))
411 (when (search-forward "\n\n" nil t)
412 (delete-region (1- (point)) (point-max)))
413 (nnheader-fold-continuation-lines)))
416 (defun gnus-request-body (article group)
417 "Request the body of ARTICLE in GROUP."
418 (let* ((gnus-command-method (gnus-find-method-for-group group))
419 (head (gnus-get-function gnus-command-method 'request-body t))
425 (gnus-cache-request-article article group))
426 (setq res (cons group article)
428 ;; Use `head' function.
430 (setq res (funcall head article (gnus-group-real-name group)
431 (nth 1 gnus-command-method))))
432 ;; Use `article' function.
434 (setq res (gnus-request-article article group)
438 (set-buffer nntp-server-buffer)
439 (goto-char (point-min))
440 (when (search-forward "\n\n" nil t)
441 (delete-region (point-min) (1- (point))))))
444 (defun gnus-request-post (gnus-command-method)
445 "Post the current buffer using GNUS-COMMAND-METHOD."
446 (when (stringp gnus-command-method)
447 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
448 (funcall (gnus-get-function gnus-command-method 'request-post)
449 (nth 1 gnus-command-method)))
451 (defun gnus-request-scan (group gnus-command-method)
452 "Request a SCAN being performed in GROUP from GNUS-COMMAND-METHOD.
453 If GROUP is nil, all groups on GNUS-COMMAND-METHOD are scanned."
454 (let ((gnus-command-method
455 (if group (gnus-find-method-for-group group) gnus-command-method))
456 (gnus-inhibit-demon t)
457 (mail-source-plugged gnus-plugged))
458 (if (or gnus-plugged (not (gnus-agent-method-p gnus-command-method)))
459 (funcall (gnus-get-function gnus-command-method 'request-scan)
460 (and group (gnus-group-real-name group))
461 (nth 1 gnus-command-method)))))
463 (defsubst gnus-request-update-info (info gnus-command-method)
464 "Request that GNUS-COMMAND-METHOD update INFO."
465 (when (stringp gnus-command-method)
466 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
467 (when (gnus-check-backend-function
468 'request-update-info (car gnus-command-method))
469 (funcall (gnus-get-function gnus-command-method 'request-update-info)
470 (gnus-group-real-name (gnus-info-group info))
471 info (nth 1 gnus-command-method))))
473 (defun gnus-request-expire-articles (articles group &optional force)
474 (let ((gnus-command-method (gnus-find-method-for-group group)))
475 (funcall (gnus-get-function gnus-command-method 'request-expire-articles)
476 articles (gnus-group-real-name group) (nth 1 gnus-command-method)
479 (defun gnus-request-move-article
480 (article group server accept-function &optional last)
481 (let ((gnus-command-method (gnus-find-method-for-group group)))
482 (funcall (gnus-get-function gnus-command-method 'request-move-article)
483 article (gnus-group-real-name group)
484 (nth 1 gnus-command-method) accept-function last)))
486 (defun gnus-request-accept-article (group &optional gnus-command-method last
488 ;; Make sure there's a newline at the end of the article.
489 (when (stringp gnus-command-method)
490 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
491 (when (and (not gnus-command-method)
493 (setq gnus-command-method (gnus-group-name-to-method group)))
494 (goto-char (point-max))
497 (let ((func (car (or gnus-command-method
498 (gnus-find-method-for-group group)))))
499 (funcall (intern (format "%s-request-accept-article" func))
500 (if (stringp group) (gnus-group-real-name group) group)
501 (cadr gnus-command-method)
504 (defun gnus-request-replace-article (article group buffer &optional no-encode)
505 (let ((func (car (gnus-group-name-to-method group))))
506 (funcall (intern (format "%s-request-replace-article" func))
507 article (gnus-group-real-name group) buffer)))
509 (defun gnus-request-associate-buffer (group)
510 (let ((gnus-command-method (gnus-find-method-for-group group)))
511 (funcall (gnus-get-function gnus-command-method 'request-associate-buffer)
512 (gnus-group-real-name group))))
514 (defun gnus-request-restore-buffer (article group)
515 "Request a new buffer restored to the state of ARTICLE."
516 (let ((gnus-command-method (gnus-find-method-for-group group)))
517 (funcall (gnus-get-function gnus-command-method 'request-restore-buffer)
518 article (gnus-group-real-name group)
519 (nth 1 gnus-command-method))))
521 (defun gnus-request-create-group (group &optional gnus-command-method args)
522 (when (stringp gnus-command-method)
523 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
524 (let ((gnus-command-method
525 (or gnus-command-method (gnus-find-method-for-group group))))
526 (funcall (gnus-get-function gnus-command-method 'request-create-group)
527 (gnus-group-real-name group) (nth 1 gnus-command-method) args)))
529 (defun gnus-request-delete-group (group &optional force)
530 (let ((gnus-command-method (gnus-find-method-for-group group)))
531 (funcall (gnus-get-function gnus-command-method 'request-delete-group)
532 (gnus-group-real-name group) force (nth 1 gnus-command-method))))
534 (defun gnus-request-rename-group (group new-name)
535 (let ((gnus-command-method (gnus-find-method-for-group group)))
536 (funcall (gnus-get-function gnus-command-method 'request-rename-group)
537 (gnus-group-real-name group)
538 (gnus-group-real-name new-name) (nth 1 gnus-command-method))))
540 (defun gnus-close-backends ()
541 ;; Send a close request to all backends that support such a request.
542 (let ((methods gnus-valid-select-methods)
543 (gnus-inhibit-demon t)
544 func gnus-command-method)
545 (while (setq gnus-command-method (pop methods))
546 (when (fboundp (setq func (intern
547 (concat (car gnus-command-method)
551 (defun gnus-asynchronous-p (gnus-command-method)
552 (let ((func (gnus-get-function gnus-command-method 'asynchronous-p t)))
556 (defun gnus-remove-denial (gnus-command-method)
557 (when (stringp gnus-command-method)
558 (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
559 (let* ((elem (assoc gnus-command-method gnus-opened-servers))
560 (status (cadr elem)))
561 ;; If this hasn't been opened before, we add it to the list.
562 (when (eq status 'denied)
563 ;; Set the status of this server.
564 (setcar (cdr elem) 'closed))))
568 ;;; gnus-int.el ends here