lisp/gnus/gnus-int.el

   1 ;;; gnus-int.el --- backend interface functions for Gnus
   2
   3 ;; Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004
   4 ;;   2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
   5
   6 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   7 ;; Keywords: news
   8
   9 ;; This file is part of GNU Emacs.
  10
  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 3 of the License, or
  14 ;; (at your option) any later version.
  15
  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.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;;; Code:
  27
  28 (eval-when-compile (require 'cl))
  29
  30 (require 'gnus)
  31 (require 'message)
  32 (require 'gnus-range)
  33
  34 (autoload 'gnus-agent-expire "gnus-agent")
  35 (autoload 'gnus-agent-regenerate-group "gnus-agent")
  36 (autoload 'gnus-agent-read-servers-validate-native "gnus-agent")
  37 (autoload 'gnus-agent-possibly-synchronize-flags-server "gnus-agent")
  38
  39 (defcustom gnus-open-server-hook nil
  40   "Hook called just before opening connection to the news server."
  41   :group 'gnus-start
  42   :type 'hook)
  43
  44 (defcustom gnus-server-unopen-status nil
  45   "The default status if the server is not able to open.
  46 If the server is covered by Gnus agent, the possible values are
  47 `denied', set the server denied; `offline', set the server offline;
  48 nil, ask user.  If the server is not covered by Gnus agent, set the
  49 server denied."
  50   :version "22.1"
  51   :group 'gnus-start
  52   :type '(choice (const :tag "Ask" nil)
  53                  (const :tag "Deny server" denied)
  54                  (const :tag "Unplug Agent" offline)))
  55
  56 (defvar gnus-internal-registry-spool-current-method nil
  57   "The current method, for the registry.")
  58
  59
  60 (defun gnus-server-opened (gnus-command-method)
  61   "Check whether a connection to GNUS-COMMAND-METHOD has been opened."
  62   (unless (eq (gnus-server-status gnus-command-method)
  63               'denied)
  64     (when (stringp gnus-command-method)
  65       (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
  66     (funcall (inline (gnus-get-function gnus-command-method 'server-opened))
  67              (nth 1 gnus-command-method))))
  68
  69 (defun gnus-status-message (gnus-command-method)
  70   "Return the status message from GNUS-COMMAND-METHOD.
  71 If GNUS-COMMAND-METHOD is a string, it is interpreted as a group
  72 name.  The method this group uses will be queried."
  73   (let ((gnus-command-method
  74          (if (stringp gnus-command-method)
  75              (gnus-find-method-for-group gnus-command-method)
  76            gnus-command-method)))
  77     (funcall (gnus-get-function gnus-command-method 'status-message)
  78              (nth 1 gnus-command-method))))
  79
  80 ;;;
  81 ;;; Server Communication
  82 ;;;
  83
  84 (defun gnus-start-news-server (&optional confirm)
  85   "Open a method for getting news.
  86 If CONFIRM is non-nil, the user will be asked for an NNTP server."
  87   (let (how)
  88     (if gnus-current-select-method
  89         ;; Stream is already opened.
  90         nil
  91       ;; Open NNTP server.
  92       (unless gnus-nntp-service
  93         (setq gnus-nntp-server nil))
  94       (when confirm
  95         ;; Read server name with completion.
  96         (setq gnus-nntp-server
  97               (gnus-completing-read "NNTP server"
  98                                     (cons gnus-nntp-server
  99                                           gnus-secondary-servers)
 100                                     nil gnus-nntp-server)))
 101
 102       (when (and gnus-nntp-server
 103                  (stringp gnus-nntp-server)
 104                  (not (string= gnus-nntp-server "")))
 105         (setq gnus-select-method
 106               (cond ((or (string= gnus-nntp-server "")
 107                          (string= gnus-nntp-server "::"))
 108                      (list 'nnspool (system-name)))
 109                     ((string-match "^:" gnus-nntp-server)
 110                      (list 'nnmh gnus-nntp-server
 111                            (list 'nnmh-directory
 112                                  (file-name-as-directory
 113                                   (expand-file-name
 114                                    (substring gnus-nntp-server 1) "~/")))
 115                            (list 'nnmh-get-new-mail nil)))
 116                     (t
 117                      (list 'nntp gnus-nntp-server)))))
 118
 119       (setq how (car gnus-select-method))
 120       (cond
 121        ((eq how 'nnspool)
 122         (require 'nnspool)
 123         (gnus-message 5 "Looking up local news spool..."))
 124        ((eq how 'nnmh)
 125         (require 'nnmh)
 126         (gnus-message 5 "Looking up mh spool..."))
 127        (t
 128         (require 'nntp)))
 129       (setq gnus-current-select-method gnus-select-method)
 130       (gnus-run-hooks 'gnus-open-server-hook)
 131
 132       ;; Partially validate agent covered methods now that the
 133       ;; gnus-select-method is known.
 134
 135       (if gnus-agent
 136           ;; NOTE: This is here for one purpose only.  By validating
 137           ;; the current select method, it converts the old 5.10.3,
 138           ;; and earlier, format to the current format.  That enables
 139           ;; the agent code within gnus-open-server to function
 140           ;; correctly.
 141           (gnus-agent-read-servers-validate-native gnus-select-method))
 142
 143       (or
 144        ;; gnus-open-server-hook might have opened it
 145        (gnus-server-opened gnus-select-method)
 146        (gnus-open-server gnus-select-method)
 147        gnus-batch-mode
 148        (gnus-y-or-n-p
 149         (format
 150          "%s (%s) open error: '%s'.  Continue? "
 151          (car gnus-select-method) (cadr gnus-select-method)
 152          (gnus-status-message gnus-select-method)))
 153        (gnus-error 1 "Couldn't open server on %s"
 154                    (nth 1 gnus-select-method))))))
 155
 156 (defun gnus-check-group (group)
 157   "Try to make sure that the server where GROUP exists is alive."
 158   (let ((method (gnus-find-method-for-group group)))
 159     (or (gnus-server-opened method)
 160         (gnus-open-server method))))
 161
 162 (defun gnus-check-server (&optional method silent)
 163   "Check whether the connection to METHOD is down.
 164 If METHOD is nil, use `gnus-select-method'.
 165 If it is down, start it up (again)."
 166   (let ((method (or method gnus-select-method))
 167         result)
 168     ;; Transform virtual server names into select methods.
 169     (when (stringp method)
 170       (setq method (gnus-server-to-method method)))
 171     (if (gnus-server-opened method)
 172         ;; The stream is already opened.
 173         t
 174       ;; Open the server.
 175       (unless silent
 176         (gnus-message 5 "Opening %s server%s..." (car method)
 177                       (if (equal (nth 1 method) "") ""
 178                         (format " on %s" (nth 1 method)))))
 179       (gnus-run-hooks 'gnus-open-server-hook)
 180       (prog1
 181           (setq result (gnus-open-server method))
 182         (unless silent
 183           (gnus-message
 184            (if result 5 3)
 185            "Opening %s server%s...%s" (car method)
 186            (if (equal (nth 1 method) "") ""
 187              (format " on %s" (nth 1 method)))
 188            (if result
 189                "done"
 190              (format "failed: %s"
 191                      (nnheader-get-report-string (car method))))))))))
 192
 193 (defun gnus-get-function (method function &optional noerror)
 194   "Return a function symbol based on METHOD and FUNCTION."
 195   ;; Translate server names into methods.
 196   (unless method
 197     (error "Attempted use of a nil select method"))
 198   (when (stringp method)
 199     (setq method (gnus-server-to-method method)))
 200   ;; Check cache of constructed names.
 201   (let* ((method-sym (if gnus-agent
 202                          (inline (gnus-agent-get-function method))
 203                        (car method)))
 204          (method-fns (get method-sym 'gnus-method-functions))
 205          (func (let ((method-fnlist-elt (assq function method-fns)))
 206                  (unless method-fnlist-elt
 207                    (setq method-fnlist-elt
 208                          (cons function
 209                                (intern (format "%s-%s" method-sym function))))
 210                    (put method-sym 'gnus-method-functions
 211                         (cons method-fnlist-elt method-fns)))
 212                  (cdr method-fnlist-elt))))
 213     ;; Maybe complain if there is no function.
 214     (unless (fboundp func)
 215       (unless (car method)
 216         (error "Trying to require a method that doesn't exist"))
 217       (require (car method))
 218       (when (not (fboundp func))
 219         (if noerror
 220             (setq func nil)
 221           (error "No such function: %s" func))))
 222     func))
 223
 224 \f
 225 ;;;
 226 ;;; Interface functions to the backends.
 227 ;;;
 228
 229 (defun gnus-method-denied-p (method)
 230   (eq (nth 1 (assoc method gnus-opened-servers))
 231       'denied))
 232
 233 (defvar gnus-backend-trace t)
 234
 235 (defun gnus-open-server (gnus-command-method)
 236   "Open a connection to GNUS-COMMAND-METHOD."
 237   (when (stringp gnus-command-method)
 238     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 239   (when gnus-backend-trace
 240     (with-current-buffer (get-buffer-create "*gnus trace*")
 241       (buffer-disable-undo)
 242       (goto-char (point-max))
 243       (insert (format-time-string "%H:%M:%S")
 244               (format " %S\n" gnus-command-method))))
 245   (let ((elem (assoc gnus-command-method gnus-opened-servers))
 246         (server (gnus-method-to-server-name gnus-command-method)))
 247     ;; If this method was previously denied, we just return nil.
 248     (if (eq (nth 1 elem) 'denied)
 249         (progn
 250           (gnus-message 1 "Denied server %s" server)
 251           nil)
 252       ;; Open the server.
 253       (let* ((open-server-function (gnus-get-function gnus-command-method 'open-server))
 254              (result
 255              (condition-case err
 256                  (funcall open-server-function
 257                           (nth 1 gnus-command-method)
 258                           (nthcdr 2 gnus-command-method))
 259                (error
 260                 (gnus-message 1 "Unable to open server %s due to: %s"
 261                               server (error-message-string err))
 262                 nil)
 263                (quit
 264                 (gnus-message 1 "Quit trying to open server %s" server)
 265                 nil)))
 266             open-offline)
 267         ;; If this hasn't been opened before, we add it to the list.
 268         (unless elem
 269           (setq elem (list gnus-command-method nil)
 270                 gnus-opened-servers (cons elem gnus-opened-servers)))
 271         ;; Set the status of this server.
 272         (setcar
 273          (cdr elem)
 274          (cond (result
 275                 (if (eq open-server-function #'nnagent-open-server)
 276                     ;; The agent's backend has a "special" status
 277                     'offline
 278                   'ok))
 279                ((and gnus-agent
 280                      (gnus-agent-method-p gnus-command-method))
 281                 (cond
 282                  (gnus-server-unopen-status
 283                   ;; Set the server's status to the unopen
 284                   ;; status.  If that status is offline,
 285                   ;; recurse to open the agent's backend.
 286                   (setq open-offline (eq gnus-server-unopen-status 'offline))
 287                   gnus-server-unopen-status)
 288                  ((not gnus-batch-mode)
 289                   (setq open-offline t)
 290                   'offline)
 291                  (t
 292                   ;; This agentized server was still denied
 293                   'denied)))
 294                (t
 295                 ;; This unagentized server must be denied
 296                 'denied)))
 297
 298         ;; NOTE: I MUST set the server's status to offline before this
 299         ;; recursive call as this status will drive the
 300         ;; gnus-get-function (called above) to return the agent's
 301         ;; backend.
 302         (if open-offline
 303             ;; Recursively open this offline server to perform the
 304             ;; open-server function of the agent's backend.
 305             (let ((gnus-server-unopen-status 'denied))
 306               ;; Bind gnus-server-unopen-status to avoid recursively
 307               ;; prompting with "go offline?".  This is only a concern
 308               ;; when the agent's backend fails to open the server.
 309               (gnus-open-server gnus-command-method))
 310           (when (and (eq (cadr elem) 'ok) gnus-agent
 311                      (gnus-agent-method-p gnus-command-method))
 312             (save-excursion
 313               (gnus-agent-possibly-synchronize-flags-server
 314                gnus-command-method)))
 315           result)))))
 316
 317 (defun gnus-close-server (gnus-command-method)
 318   "Close the connection to GNUS-COMMAND-METHOD."
 319   (when (stringp gnus-command-method)
 320     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 321   (funcall (gnus-get-function gnus-command-method 'close-server)
 322            (nth 1 gnus-command-method)))
 323
 324 (defun gnus-request-list (gnus-command-method)
 325   "Request the active file from GNUS-COMMAND-METHOD."
 326   (when (stringp gnus-command-method)
 327     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 328   (funcall (gnus-get-function gnus-command-method 'request-list)
 329            (nth 1 gnus-command-method)))
 330
 331 (defun gnus-finish-retrieve-group-infos (gnus-command-method infos data)
 332   "Read and update infos from GNUS-COMMAND-METHOD."
 333   (when (stringp gnus-command-method)
 334     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 335   (funcall (gnus-get-function gnus-command-method 'finish-retrieve-group-infos)
 336            (nth 1 gnus-command-method)
 337            infos data))
 338
 339 (defun gnus-retrieve-group-data-early (gnus-command-method infos)
 340   "Start early async retrival of data from GNUS-COMMAND-METHOD."
 341   (when (stringp gnus-command-method)
 342     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 343   (funcall (gnus-get-function gnus-command-method 'retrieve-group-data-early)
 344            (nth 1 gnus-command-method)
 345            infos))
 346
 347 (defun gnus-request-list-newsgroups (gnus-command-method)
 348   "Request the newsgroups file from GNUS-COMMAND-METHOD."
 349   (when (stringp gnus-command-method)
 350     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 351   (funcall (gnus-get-function gnus-command-method 'request-list-newsgroups)
 352            (nth 1 gnus-command-method)))
 353
 354 (defun gnus-request-newgroups (date gnus-command-method)
 355   "Request all new groups since DATE from GNUS-COMMAND-METHOD."
 356   (when (stringp gnus-command-method)
 357     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 358   (let ((func (gnus-get-function gnus-command-method 'request-newgroups t)))
 359     (when func
 360       (funcall func date (nth 1 gnus-command-method)))))
 361
 362 (defun gnus-request-regenerate (gnus-command-method)
 363   "Request a data generation from GNUS-COMMAND-METHOD."
 364   (when (stringp gnus-command-method)
 365     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 366   (funcall (gnus-get-function gnus-command-method 'request-regenerate)
 367            (nth 1 gnus-command-method)))
 368
 369 (defun gnus-request-compact-group (group)
 370   (let* ((method (gnus-find-method-for-group group))
 371          (gnus-command-method method)
 372          (result
 373           (funcall (gnus-get-function gnus-command-method
 374                                       'request-compact-group)
 375                    (gnus-group-real-name group)
 376                    (nth 1 gnus-command-method) t)))
 377     result))
 378
 379 (defun gnus-request-compact (gnus-command-method)
 380   "Request groups compaction  from GNUS-COMMAND-METHOD."
 381   (when (stringp gnus-command-method)
 382     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 383   (funcall (gnus-get-function gnus-command-method 'request-compact)
 384            (nth 1 gnus-command-method)))
 385
 386 (defun gnus-request-group (group &optional dont-check gnus-command-method info)
 387   "Request GROUP.  If DONT-CHECK, no information is required."
 388   (let ((gnus-command-method
 389          (or gnus-command-method (inline (gnus-find-method-for-group group)))))
 390     (when (stringp gnus-command-method)
 391       (setq gnus-command-method
 392             (inline (gnus-server-to-method gnus-command-method))))
 393     (funcall (inline (gnus-get-function gnus-command-method 'request-group))
 394              (gnus-group-real-name group) (nth 1 gnus-command-method)
 395              dont-check
 396              info)))
 397
 398 (defun gnus-list-active-group (group)
 399   "Request active information on GROUP."
 400   (let ((gnus-command-method (gnus-find-method-for-group group))
 401         (func 'list-active-group))
 402     (when (gnus-check-backend-function func group)
 403       (funcall (gnus-get-function gnus-command-method func)
 404                (gnus-group-real-name group) (nth 1 gnus-command-method)))))
 405
 406 (defun gnus-request-group-description (group)
 407   "Request a description of GROUP."
 408   (let ((gnus-command-method (gnus-find-method-for-group group))
 409         (func 'request-group-description))
 410     (when (gnus-check-backend-function func group)
 411       (funcall (gnus-get-function gnus-command-method func)
 412                (gnus-group-real-name group) (nth 1 gnus-command-method)))))
 413
 414 (defun gnus-request-group-articles (group)
 415   "Request a list of existing articles in GROUP."
 416   (let ((gnus-command-method (gnus-find-method-for-group group))
 417         (func 'request-group-articles))
 418     (when (gnus-check-backend-function func group)
 419       (funcall (gnus-get-function gnus-command-method func)
 420                (gnus-group-real-name group) (nth 1 gnus-command-method)))))
 421
 422 (defun gnus-close-group (group)
 423   "Request the GROUP be closed."
 424   (let ((gnus-command-method (inline (gnus-find-method-for-group group))))
 425     (funcall (gnus-get-function gnus-command-method 'close-group)
 426              (gnus-group-real-name group) (nth 1 gnus-command-method))))
 427
 428 (defun gnus-retrieve-headers (articles group &optional fetch-old)
 429   "Request headers for ARTICLES in GROUP.
 430 If FETCH-OLD, retrieve all headers (or some subset thereof) in the group."
 431   (let ((gnus-command-method (gnus-find-method-for-group group)))
 432     (cond
 433      ((and gnus-use-cache (numberp (car articles)))
 434       (gnus-cache-retrieve-headers articles group fetch-old))
 435      ((and gnus-agent (gnus-online gnus-command-method)
 436            (gnus-agent-method-p gnus-command-method))
 437       (gnus-agent-retrieve-headers articles group fetch-old))
 438      (t
 439       (funcall (gnus-get-function gnus-command-method 'retrieve-headers)
 440                articles (gnus-group-real-name group)
 441                (nth 1 gnus-command-method) fetch-old)))))
 442
 443 (defun gnus-retrieve-articles (articles group)
 444   "Request ARTICLES in GROUP."
 445   (let ((gnus-command-method (gnus-find-method-for-group group)))
 446     (funcall (gnus-get-function gnus-command-method 'retrieve-articles)
 447              articles (gnus-group-real-name group)
 448              (nth 1 gnus-command-method))))
 449
 450 (defun gnus-retrieve-groups (groups gnus-command-method)
 451   "Request active information on GROUPS from GNUS-COMMAND-METHOD."
 452   (when (stringp gnus-command-method)
 453     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 454   (funcall (gnus-get-function gnus-command-method 'retrieve-groups)
 455            groups (nth 1 gnus-command-method)))
 456
 457 (defun gnus-request-type (group &optional article)
 458   "Return the type (`post' or `mail') of GROUP (and ARTICLE)."
 459   (let ((gnus-command-method (gnus-find-method-for-group group)))
 460     (if (not (gnus-check-backend-function
 461               'request-type (car gnus-command-method)))
 462         'unknown
 463       (funcall (gnus-get-function gnus-command-method 'request-type)
 464                (gnus-group-real-name group) article))))
 465
 466 (defun gnus-request-set-mark (group action)
 467   "Set marks on articles in the back end."
 468   (let ((gnus-command-method (gnus-find-method-for-group group)))
 469     (if (not (gnus-check-backend-function
 470               'request-set-mark (car gnus-command-method)))
 471         action
 472       (funcall (gnus-get-function gnus-command-method 'request-set-mark)
 473                (gnus-group-real-name group) action
 474                (nth 1 gnus-command-method)))))
 475
 476 (defun gnus-request-update-mark (group article mark)
 477   "Allow the back end to change the mark the user tries to put on an article."
 478   (let ((gnus-command-method (gnus-find-method-for-group group)))
 479     (if (not (gnus-check-backend-function
 480               'request-update-mark (car gnus-command-method)))
 481         mark
 482       (funcall (gnus-get-function gnus-command-method 'request-update-mark)
 483                (gnus-group-real-name group) article mark))))
 484
 485 (defun gnus-request-article (article group &optional buffer)
 486   "Request the ARTICLE in GROUP.
 487 ARTICLE can either be an article number or an article Message-ID.
 488 If BUFFER, insert the article in that group."
 489   (let ((gnus-command-method (gnus-find-method-for-group group)))
 490     (funcall (gnus-get-function gnus-command-method 'request-article)
 491              article (gnus-group-real-name group)
 492              (nth 1 gnus-command-method) buffer)))
 493
 494 (defun gnus-request-head (article group)
 495   "Request the head of ARTICLE in GROUP."
 496   (let* ((gnus-command-method (gnus-find-method-for-group group))
 497          (head (gnus-get-function gnus-command-method 'request-head t))
 498          res clean-up)
 499     (cond
 500      ;; Check the cache.
 501      ((and gnus-use-cache
 502            (numberp article)
 503            (gnus-cache-request-article article group))
 504       (setq res (cons group article)
 505             clean-up t))
 506      ;; Check the agent cache.
 507      ((gnus-agent-request-article article group)
 508       (setq res (cons group article)
 509             clean-up t))
 510      ;; Use `head' function.
 511      ((fboundp head)
 512       (setq res (funcall head article (gnus-group-real-name group)
 513                          (nth 1 gnus-command-method))))
 514      ;; Use `article' function.
 515      (t
 516       (setq res (gnus-request-article article group)
 517             clean-up t)))
 518     (when clean-up
 519       (with-current-buffer nntp-server-buffer
 520         (goto-char (point-min))
 521         (when (search-forward "\n\n" nil t)
 522           (delete-region (1- (point)) (point-max)))
 523         (nnheader-fold-continuation-lines)))
 524     res))
 525
 526 (defun gnus-request-body (article group)
 527   "Request the body of ARTICLE in GROUP."
 528   (let* ((gnus-command-method (gnus-find-method-for-group group))
 529          (head (gnus-get-function gnus-command-method 'request-body t))
 530          res clean-up)
 531     (cond
 532      ;; Check the cache.
 533      ((and gnus-use-cache
 534            (numberp article)
 535            (gnus-cache-request-article article group))
 536       (setq res (cons group article)
 537             clean-up t))
 538      ;; Check the agent cache.
 539      ((gnus-agent-request-article article group)
 540       (setq res (cons group article)
 541             clean-up t))
 542      ;; Use `head' function.
 543      ((fboundp head)
 544       (setq res (funcall head article (gnus-group-real-name group)
 545                          (nth 1 gnus-command-method))))
 546      ;; Use `article' function.
 547      (t
 548       (setq res (gnus-request-article article group)
 549             clean-up t)))
 550     (when clean-up
 551       (with-current-buffer nntp-server-buffer
 552         (goto-char (point-min))
 553         (when (search-forward "\n\n" nil t)
 554           (delete-region (point-min) (1- (point))))))
 555     res))
 556
 557 (defun gnus-request-post (gnus-command-method)
 558   "Post the current buffer using GNUS-COMMAND-METHOD."
 559   (when (stringp gnus-command-method)
 560     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 561   (funcall (gnus-get-function gnus-command-method 'request-post)
 562            (nth 1 gnus-command-method)))
 563
 564 (defun gnus-request-expunge-group (group gnus-command-method)
 565   "Expunge GROUP, which is removing articles that have been marked as deleted."
 566   (when (stringp gnus-command-method)
 567     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 568   (funcall (gnus-get-function gnus-command-method 'request-expunge-group)
 569            (gnus-group-real-name group)
 570            (nth 1 gnus-command-method)))
 571
 572 (defun gnus-request-scan (group gnus-command-method)
 573   "Request a SCAN being performed in GROUP from GNUS-COMMAND-METHOD.
 574 If GROUP is nil, all groups on GNUS-COMMAND-METHOD are scanned."
 575   (let ((gnus-command-method
 576          (if group (gnus-find-method-for-group group) gnus-command-method))
 577         (gnus-inhibit-demon t)
 578         (mail-source-plugged gnus-plugged))
 579     (when (or gnus-plugged
 580               (not (gnus-agent-method-p gnus-command-method)))
 581       (setq gnus-internal-registry-spool-current-method gnus-command-method)
 582       (funcall (gnus-get-function gnus-command-method 'request-scan)
 583                (and group (gnus-group-real-name group))
 584                (nth 1 gnus-command-method)))))
 585
 586 (defun gnus-request-update-info (info gnus-command-method)
 587   (when (gnus-check-backend-function
 588          'request-update-info (car gnus-command-method))
 589     (when (stringp gnus-command-method)
 590       (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 591     (funcall (gnus-get-function gnus-command-method 'request-update-info)
 592              (gnus-group-real-name (gnus-info-group info)) info
 593              (nth 1 gnus-command-method))))
 594
 595 (defsubst gnus-request-marks (info gnus-command-method)
 596   "Request that GNUS-COMMAND-METHOD update INFO."
 597   (when (stringp gnus-command-method)
 598     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 599   (when (gnus-check-backend-function
 600          'request-marks (car gnus-command-method))
 601     (let ((group (gnus-info-group info)))
 602       (and (funcall (gnus-get-function gnus-command-method
 603                                        'request-update-info)
 604                     (gnus-group-real-name group)
 605                     info (nth 1 gnus-command-method))
 606            ;; If the minimum article number is greater than 1, then all
 607            ;; smaller article numbers are known not to exist; we'll
 608            ;; artificially add those to the 'read range.
 609            (let* ((active (gnus-active group))
 610                   (min (car active)))
 611              (when (> min 1)
 612                (let* ((range (if (= min 2) 1 (cons 1 (1- min))))
 613                       (read (gnus-info-read info))
 614                       (new-read (gnus-range-add read (list range))))
 615                  (gnus-info-set-read info new-read)))
 616              info)))))
 617
 618 (defun gnus-request-expire-articles (articles group &optional force)
 619   (let* ((gnus-command-method (gnus-find-method-for-group group))
 620          (gnus-inhibit-demon t)
 621          (not-deleted
 622           (funcall
 623            (gnus-get-function gnus-command-method 'request-expire-articles)
 624            articles (gnus-group-real-name group) (nth 1 gnus-command-method)
 625            force)))
 626     (when (and gnus-agent
 627                (gnus-agent-method-p gnus-command-method))
 628       (let ((expired-articles (gnus-sorted-difference articles not-deleted)))
 629         (when expired-articles
 630           (gnus-agent-expire expired-articles group 'force))))
 631     not-deleted))
 632
 633 (defun gnus-request-move-article (article group server accept-function
 634                                           &optional last move-is-internal)
 635   (let* ((gnus-command-method (gnus-find-method-for-group group))
 636          (result (funcall (gnus-get-function gnus-command-method
 637                                              'request-move-article)
 638                           article (gnus-group-real-name group)
 639                           (nth 1 gnus-command-method) accept-function last move-is-internal)))
 640     (when (and result gnus-agent
 641                (gnus-agent-method-p gnus-command-method))
 642       (gnus-agent-unfetch-articles group (list article)))
 643     result))
 644
 645 (defun gnus-request-accept-article (group &optional gnus-command-method last
 646                                           no-encode)
 647   ;; Make sure there's a newline at the end of the article.
 648   (when (stringp gnus-command-method)
 649     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 650   (when (and (not gnus-command-method)
 651              (stringp group))
 652     (setq gnus-command-method (or (gnus-find-method-for-group group)
 653                                   (gnus-group-name-to-method group))))
 654   (goto-char (point-max))
 655   (unless (bolp)
 656     (insert "\n"))
 657   (unless no-encode
 658     (let ((message-options message-options))
 659       (message-options-set-recipient)
 660       (save-restriction
 661         (message-narrow-to-head)
 662         (let ((mail-parse-charset message-default-charset))
 663           (mail-encode-encoded-word-buffer)))
 664       (message-encode-message-body)))
 665   (let ((gnus-command-method (or gnus-command-method
 666                                  (gnus-find-method-for-group group)))
 667         (result
 668          (funcall
 669           (gnus-get-function gnus-command-method 'request-accept-article)
 670           (if (stringp group) (gnus-group-real-name group) group)
 671           (cadr gnus-command-method)
 672           last)))
 673     (when (and gnus-agent (gnus-agent-method-p gnus-command-method))
 674       (gnus-agent-regenerate-group group (list (cdr result))))
 675     result))
 676
 677 (defun gnus-request-replace-article (article group buffer &optional no-encode)
 678   (unless no-encode
 679     (let ((message-options message-options))
 680       (message-options-set-recipient)
 681       (save-restriction
 682         (message-narrow-to-head)
 683         (let ((mail-parse-charset message-default-charset))
 684           (mail-encode-encoded-word-buffer)))
 685       (message-encode-message-body)))
 686   (let* ((func (car (gnus-group-name-to-method group)))
 687          (result (funcall (intern (format "%s-request-replace-article" func))
 688                           article (gnus-group-real-name group) buffer)))
 689     (when (and gnus-agent (gnus-agent-method-p gnus-command-method))
 690       (gnus-agent-regenerate-group group (list article)))
 691     result))
 692
 693 (defun gnus-request-associate-buffer (group)
 694   (let ((gnus-command-method (gnus-find-method-for-group group)))
 695     (funcall (gnus-get-function gnus-command-method 'request-associate-buffer)
 696              (gnus-group-real-name group))))
 697
 698 (defun gnus-request-restore-buffer (article group)
 699   "Request a new buffer restored to the state of ARTICLE."
 700   (let ((gnus-command-method (gnus-find-method-for-group group)))
 701     (funcall (gnus-get-function gnus-command-method 'request-restore-buffer)
 702              article (gnus-group-real-name group)
 703              (nth 1 gnus-command-method))))
 704
 705 (defun gnus-request-create-group (group &optional gnus-command-method args)
 706   (when (stringp gnus-command-method)
 707     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 708   (let ((gnus-command-method
 709          (or gnus-command-method (gnus-find-method-for-group group))))
 710     (funcall (gnus-get-function gnus-command-method 'request-create-group)
 711              (gnus-group-real-name group) (nth 1 gnus-command-method) args)))
 712
 713 (defun gnus-request-delete-group (group &optional force)
 714   (let* ((gnus-command-method (gnus-find-method-for-group group))
 715          (result
 716           (funcall (gnus-get-function gnus-command-method 'request-delete-group)
 717                    (gnus-group-real-name group) force (nth 1 gnus-command-method))))
 718     (when result
 719       (gnus-cache-delete-group group)
 720       (gnus-agent-delete-group group))
 721     result))
 722
 723 (defun gnus-request-rename-group (group new-name)
 724   (let* ((gnus-command-method (gnus-find-method-for-group group))
 725          (result
 726           (funcall (gnus-get-function gnus-command-method 'request-rename-group)
 727                    (gnus-group-real-name group)
 728                    (gnus-group-real-name new-name) (nth 1 gnus-command-method))))
 729     (when result
 730       (gnus-cache-rename-group group new-name)
 731       (gnus-agent-rename-group group new-name))
 732     result))
 733
 734 (defun gnus-close-backends ()
 735   ;; Send a close request to all backends that support such a request.
 736   (let ((methods gnus-valid-select-methods)
 737         (gnus-inhibit-demon t)
 738         func gnus-command-method)
 739     (while (setq gnus-command-method (pop methods))
 740       (when (fboundp (setq func (intern
 741                                  (concat (car gnus-command-method)
 742                                          "-request-close"))))
 743         (funcall func)))))
 744
 745 (defun gnus-asynchronous-p (gnus-command-method)
 746   (let ((func (gnus-get-function gnus-command-method 'asynchronous-p t)))
 747     (when (fboundp func)
 748       (funcall func))))
 749
 750 (defun gnus-remove-denial (gnus-command-method)
 751   (when (stringp gnus-command-method)
 752     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 753   (let* ((elem (assoc gnus-command-method gnus-opened-servers))
 754          (status (cadr elem)))
 755     ;; If this hasn't been opened before, we add it to the list.
 756     (when (eq status 'denied)
 757       ;; Set the status of this server.
 758       (setcar (cdr elem) 'closed))))
 759
 760 (provide 'gnus-int)
 761
 762 ;;; gnus-int.el ends here