lisp/gnus/gnus-int.el

   1 ;;; gnus-int.el --- backend interface functions for Gnus
   2
   3 ;; Copyright (C) 1996-2014 Free Software Foundation, Inc.
   4
   5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   6 ;; Keywords: news
   7
   8 ;; This file is part of GNU Emacs.
   9
  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 3 of the License, or
  13 ;; (at your option) any later version.
  14
  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.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  22
  23 ;;; Commentary:
  24
  25 ;;; Code:
  26
  27 (eval-when-compile (require 'cl))
  28
  29 (require 'gnus)
  30 (require 'message)
  31 (require 'gnus-range)
  32
  33 (autoload 'gnus-run-hook-with-args "gnus-util")
  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-after-set-mark-hook nil
  45   "Hook called just after marks are set in a group."
  46   :version "24.1"
  47   :group 'gnus-start
  48   :type 'hook)
  49
  50 (defcustom gnus-before-update-mark-hook nil
  51   "Hook called just before marks are updated in a group."
  52   :version "24.1"
  53   :group 'gnus-start
  54   :type 'hook)
  55
  56 (defcustom gnus-server-unopen-status nil
  57   "The default status if the server is not able to open.
  58 If the server is covered by Gnus agent, the possible values are
  59 `denied', set the server denied; `offline', set the server offline;
  60 nil, ask user.  If the server is not covered by Gnus agent, set the
  61 server denied."
  62   :version "22.1"
  63   :group 'gnus-start
  64   :type '(choice (const :tag "Ask" nil)
  65                  (const :tag "Deny server" denied)
  66                  (const :tag "Unplug Agent" offline)))
  67
  68 (defcustom gnus-nntp-server nil
  69   "The name of the host running the NNTP server."
  70   :group 'gnus-server
  71   :type '(choice (const :tag "disable" nil)
  72                  string))
  73 (make-obsolete-variable 'gnus-nntp-server 'gnus-select-method "24.1")
  74
  75 (defvar gnus-internal-registry-spool-current-method nil
  76   "The current method, for the registry.")
  77
  78
  79 (defun gnus-server-opened (gnus-command-method)
  80   "Check whether a connection to GNUS-COMMAND-METHOD has been opened."
  81   (unless (eq (gnus-server-status gnus-command-method)
  82               'denied)
  83     (when (stringp gnus-command-method)
  84       (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
  85     (funcall (inline (gnus-get-function gnus-command-method 'server-opened))
  86              (nth 1 gnus-command-method))))
  87
  88 (defun gnus-status-message (gnus-command-method)
  89   "Return the status message from GNUS-COMMAND-METHOD.
  90 If GNUS-COMMAND-METHOD is a string, it is interpreted as a group
  91 name.  The method this group uses will be queried."
  92   (let ((gnus-command-method
  93          (if (stringp gnus-command-method)
  94              (gnus-find-method-for-group gnus-command-method)
  95            gnus-command-method)))
  96     (funcall (gnus-get-function gnus-command-method 'status-message)
  97              (nth 1 gnus-command-method))))
  98
  99 ;;;
 100 ;;; Server Communication
 101 ;;;
 102
 103 (defun gnus-start-news-server (&optional confirm)
 104   "Open a method for getting news.
 105 If CONFIRM is non-nil, the user will be asked for an NNTP server."
 106   (let (how)
 107     (if gnus-current-select-method
 108         ;; Stream is already opened.
 109         nil
 110       ;; Open NNTP server.
 111       (when confirm
 112         ;; Read server name with completion.
 113         (setq gnus-nntp-server
 114               (gnus-completing-read "NNTP server"
 115                                     (cons gnus-nntp-server
 116                                           (if (boundp 'gnus-secondary-servers)
 117                                               gnus-secondary-servers))
 118                                     nil gnus-nntp-server)))
 119
 120       (when (and gnus-nntp-server
 121                  (stringp gnus-nntp-server)
 122                  (not (string= gnus-nntp-server "")))
 123         (setq gnus-select-method
 124               (cond ((or (string= gnus-nntp-server "")
 125                          (string= gnus-nntp-server "::"))
 126                      (list 'nnspool (system-name)))
 127                     ((string-match "^:" gnus-nntp-server)
 128                      (list 'nnmh gnus-nntp-server
 129                            (list 'nnmh-directory
 130                                  (file-name-as-directory
 131                                   (expand-file-name
 132                                    (substring gnus-nntp-server 1) "~/")))
 133                            (list 'nnmh-get-new-mail nil)))
 134                     (t
 135                      (list 'nntp gnus-nntp-server)))))
 136
 137       (setq how (car gnus-select-method))
 138       (cond
 139        ((eq how 'nnspool)
 140         (require 'nnspool)
 141         (gnus-message 5 "Looking up local news spool..."))
 142        ((eq how 'nnmh)
 143         (require 'nnmh)
 144         (gnus-message 5 "Looking up mh spool..."))
 145        (t
 146         (require 'nntp)))
 147       (setq gnus-current-select-method gnus-select-method)
 148       (gnus-run-hooks 'gnus-open-server-hook)
 149
 150       ;; Partially validate agent covered methods now that the
 151       ;; gnus-select-method is known.
 152
 153       (if gnus-agent
 154           ;; NOTE: This is here for one purpose only.  By validating
 155           ;; the current select method, it converts the old 5.10.3,
 156           ;; and earlier, format to the current format.  That enables
 157           ;; the agent code within gnus-open-server to function
 158           ;; correctly.
 159           (gnus-agent-read-servers-validate-native gnus-select-method))
 160
 161       (or
 162        ;; gnus-open-server-hook might have opened it
 163        (gnus-server-opened gnus-select-method)
 164        (gnus-open-server gnus-select-method)
 165        gnus-batch-mode
 166        (gnus-y-or-n-p
 167         (format
 168          "%s (%s) open error: '%s'.  Continue? "
 169          (car gnus-select-method) (cadr gnus-select-method)
 170          (gnus-status-message gnus-select-method)))
 171        (gnus-error 1 "Couldn't open server on %s"
 172                    (nth 1 gnus-select-method))))))
 173
 174 (defun gnus-check-group (group)
 175   "Try to make sure that the server where GROUP exists is alive."
 176   (let ((method (gnus-find-method-for-group group)))
 177     (or (gnus-server-opened method)
 178         (gnus-open-server method))))
 179
 180 (defun gnus-check-server (&optional method silent)
 181   "Check whether the connection to METHOD is down.
 182 If METHOD is nil, use `gnus-select-method'.
 183 If it is down, start it up (again)."
 184   (let ((method (or method gnus-select-method))
 185         result)
 186     ;; Transform virtual server names into select methods.
 187     (when (stringp method)
 188       (setq method (gnus-server-to-method method)))
 189     (if (gnus-server-opened method)
 190         ;; The stream is already opened.
 191         t
 192       ;; Open the server.
 193       (unless silent
 194         (gnus-message 5 "Opening %s server%s..." (car method)
 195                       (if (equal (nth 1 method) "") ""
 196                         (format " on %s" (nth 1 method)))))
 197       (gnus-run-hooks 'gnus-open-server-hook)
 198       (prog1
 199           (setq result (gnus-open-server method))
 200         (unless silent
 201           (gnus-message
 202            (if result 5 3)
 203            "Opening %s server%s...%s" (car method)
 204            (if (equal (nth 1 method) "") ""
 205              (format " on %s" (nth 1 method)))
 206            (if result
 207                "done"
 208              (format "failed: %s"
 209                      (nnheader-get-report-string (car method))))))))))
 210
 211 (defun gnus-get-function (method function &optional noerror)
 212   "Return a function symbol based on METHOD and FUNCTION."
 213   ;; Translate server names into methods.
 214   (unless method
 215     (error "Attempted use of a nil select method"))
 216   (when (stringp method)
 217     (setq method (gnus-server-to-method method)))
 218   ;; Check cache of constructed names.
 219   (let* ((method-sym (if gnus-agent
 220                          (inline (gnus-agent-get-function method))
 221                        (car method)))
 222          (method-fns (get method-sym 'gnus-method-functions))
 223          (func (let ((method-fnlist-elt (assq function method-fns)))
 224                  (unless method-fnlist-elt
 225                    (setq method-fnlist-elt
 226                          (cons function
 227                                (intern (format "%s-%s" method-sym function))))
 228                    (put method-sym 'gnus-method-functions
 229                         (cons method-fnlist-elt method-fns)))
 230                  (cdr method-fnlist-elt))))
 231     ;; Maybe complain if there is no function.
 232     (unless (fboundp func)
 233       (unless (car method)
 234         (error "Trying to require a method that doesn't exist"))
 235       (require (car method))
 236       (when (not (fboundp func))
 237         (if noerror
 238             (setq func nil)
 239           (error "No such function: %s" func))))
 240     func))
 241
 242 \f
 243 ;;;
 244 ;;; Interface functions to the backends.
 245 ;;;
 246
 247 (defun gnus-method-denied-p (method)
 248   (eq (nth 1 (assoc method gnus-opened-servers))
 249       'denied))
 250
 251 (defvar gnus-backend-trace nil)
 252 (defvar gnus-backend-trace-elapsed nil)
 253
 254 (defun gnus-backend-trace (type form)
 255   (when gnus-backend-trace
 256     (with-current-buffer (get-buffer-create "*gnus trace*")
 257       (buffer-disable-undo)
 258       (goto-char (point-max))
 259       (insert (format-time-string "%H:%M:%S")
 260               (format " %.2fs %s %S\n"
 261                       (if (numberp gnus-backend-trace-elapsed)
 262                           (- (float-time) gnus-backend-trace-elapsed)
 263                         0)
 264                       type form))
 265       (setq gnus-backend-trace-elapsed (float-time)))))
 266
 267 (defun gnus-open-server (gnus-command-method)
 268   "Open a connection to GNUS-COMMAND-METHOD."
 269   (when (stringp gnus-command-method)
 270     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 271   (gnus-backend-trace :opening gnus-command-method)
 272   (let ((elem (assoc gnus-command-method gnus-opened-servers))
 273         (server (gnus-method-to-server-name gnus-command-method)))
 274     ;; If this method was previously denied, we just return nil.
 275     (if (eq (nth 1 elem) 'denied)
 276         (progn
 277           (gnus-message
 278            1 "Server %s previously determined to be down; not retrying" server)
 279           nil)
 280       ;; Open the server.
 281       (let* ((open-server-function
 282               (gnus-get-function gnus-command-method 'open-server))
 283              (result
 284               (condition-case err
 285                   (funcall open-server-function
 286                            (nth 1 gnus-command-method)
 287                            (nthcdr 2 gnus-command-method))
 288                 (error
 289                  (gnus-message 1 "Unable to open server %s due to: %s"
 290                                server (error-message-string err))
 291                  nil)
 292                 (quit
 293                  (if debug-on-quit
 294                      (debug "Quit")
 295                    (gnus-message 1 "Quit trying to open server %s" server))
 296                  nil)))
 297              open-offline)
 298         ;; If this hasn't been opened before, we add it to the list.
 299         (unless elem
 300           (setq elem (list gnus-command-method nil)
 301                 gnus-opened-servers (cons elem gnus-opened-servers)))
 302         ;; Set the status of this server.
 303         (setcar
 304          (cdr elem)
 305          (cond (result
 306                 (if (eq open-server-function 'nnagent-open-server)
 307                     ;; The agent's backend has a "special" status
 308                     'offline
 309                   'ok))
 310                ((and gnus-agent
 311                      (gnus-agent-method-p gnus-command-method))
 312                 (cond
 313                  (gnus-server-unopen-status
 314                   ;; Set the server's status to the unopen
 315                   ;; status.  If that status is offline,
 316                   ;; recurse to open the agent's backend.
 317                   (setq open-offline (eq gnus-server-unopen-status 'offline))
 318                   gnus-server-unopen-status)
 319                  ((not gnus-batch-mode)
 320                   (setq open-offline t)
 321                   'offline)
 322                  (t
 323                   ;; This agentized server was still denied
 324                   'denied)))
 325                (t
 326                 ;; This unagentized server must be denied
 327                 'denied)))
 328
 329         ;; NOTE: I MUST set the server's status to offline before this
 330         ;; recursive call as this status will drive the
 331         ;; gnus-get-function (called above) to return the agent's
 332         ;; backend.
 333         (if open-offline
 334             ;; Recursively open this offline server to perform the
 335             ;; open-server function of the agent's backend.
 336             (let ((gnus-server-unopen-status 'denied))
 337               ;; Bind gnus-server-unopen-status to avoid recursively
 338               ;; prompting with "go offline?".  This is only a concern
 339               ;; when the agent's backend fails to open the server.
 340               (gnus-open-server gnus-command-method))
 341           (when (and (eq (cadr elem) 'ok) gnus-agent
 342                      (gnus-agent-method-p gnus-command-method))
 343             (save-excursion
 344               (gnus-agent-possibly-synchronize-flags-server
 345                gnus-command-method)))
 346           (gnus-backend-trace :opened gnus-command-method)
 347           result)))))
 348
 349 (defun gnus-close-server (gnus-command-method)
 350   "Close the connection to GNUS-COMMAND-METHOD."
 351   (when (stringp gnus-command-method)
 352     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 353   (funcall (gnus-get-function gnus-command-method 'close-server)
 354            (nth 1 gnus-command-method)))
 355
 356 (defun gnus-request-list (gnus-command-method)
 357   "Request the active file from GNUS-COMMAND-METHOD."
 358   (when (stringp gnus-command-method)
 359     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 360   (funcall (gnus-get-function gnus-command-method 'request-list)
 361            (nth 1 gnus-command-method)))
 362
 363 (defun gnus-finish-retrieve-group-infos (gnus-command-method infos data)
 364   "Read and update infos from GNUS-COMMAND-METHOD."
 365   (when (stringp gnus-command-method)
 366     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 367   (gnus-backend-trace :finishing gnus-command-method)
 368   (prog1
 369       (funcall (gnus-get-function gnus-command-method
 370                                   'finish-retrieve-group-infos)
 371                (nth 1 gnus-command-method)
 372                infos data)
 373     (gnus-backend-trace :finished gnus-command-method)))
 374
 375 (defun gnus-retrieve-group-data-early (gnus-command-method infos)
 376   "Start early async retrieval of data from GNUS-COMMAND-METHOD."
 377   (when (stringp gnus-command-method)
 378     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 379   (funcall (gnus-get-function gnus-command-method 'retrieve-group-data-early)
 380            (nth 1 gnus-command-method)
 381            infos))
 382
 383 (defun gnus-request-list-newsgroups (gnus-command-method)
 384   "Request the newsgroups file from GNUS-COMMAND-METHOD."
 385   (when (stringp gnus-command-method)
 386     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 387   (funcall (gnus-get-function gnus-command-method 'request-list-newsgroups)
 388            (nth 1 gnus-command-method)))
 389
 390 (defun gnus-request-newgroups (date gnus-command-method)
 391   "Request all new groups since DATE from GNUS-COMMAND-METHOD."
 392   (when (stringp gnus-command-method)
 393     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 394   (let ((func (gnus-get-function gnus-command-method 'request-newgroups t)))
 395     (when func
 396       (funcall func date (nth 1 gnus-command-method)))))
 397
 398 (defun gnus-request-regenerate (gnus-command-method)
 399   "Request a data generation from GNUS-COMMAND-METHOD."
 400   (when (stringp gnus-command-method)
 401     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 402   (funcall (gnus-get-function gnus-command-method 'request-regenerate)
 403            (nth 1 gnus-command-method)))
 404
 405 (defun gnus-request-compact-group (group)
 406   (let* ((method (gnus-find-method-for-group group))
 407          (gnus-command-method method)
 408          (result
 409           (funcall (gnus-get-function gnus-command-method
 410                                       'request-compact-group)
 411                    (gnus-group-real-name group)
 412                    (nth 1 gnus-command-method) t)))
 413     result))
 414
 415 (defun gnus-request-compact (gnus-command-method)
 416   "Request groups compaction from GNUS-COMMAND-METHOD."
 417   (when (stringp gnus-command-method)
 418     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 419   (funcall (gnus-get-function gnus-command-method 'request-compact)
 420            (nth 1 gnus-command-method)))
 421
 422 (defun gnus-request-group (group &optional dont-check gnus-command-method info)
 423   "Request GROUP.  If DONT-CHECK, no information is required."
 424   (let ((gnus-command-method
 425          (or gnus-command-method (inline (gnus-find-method-for-group group)))))
 426     (when (stringp gnus-command-method)
 427       (setq gnus-command-method
 428             (inline (gnus-server-to-method gnus-command-method))))
 429     (funcall (inline (gnus-get-function gnus-command-method 'request-group))
 430              (gnus-group-real-name group) (nth 1 gnus-command-method)
 431              dont-check
 432              info)))
 433
 434 (defun gnus-request-group-description (group)
 435   "Request a description of GROUP."
 436   (let ((gnus-command-method (gnus-find-method-for-group group))
 437         (func 'request-group-description))
 438     (when (gnus-check-backend-function func group)
 439       (funcall (gnus-get-function gnus-command-method func)
 440                (gnus-group-real-name group) (nth 1 gnus-command-method)))))
 441
 442 (defun gnus-close-group (group)
 443   "Request the GROUP be closed."
 444   (let ((gnus-command-method (inline (gnus-find-method-for-group group))))
 445     (funcall (gnus-get-function gnus-command-method 'close-group)
 446              (gnus-group-real-name group) (nth 1 gnus-command-method))))
 447
 448 (defun gnus-retrieve-headers (articles group &optional fetch-old)
 449   "Request headers for ARTICLES in GROUP.
 450 If FETCH-OLD, retrieve all headers (or some subset thereof) in the group."
 451   (let ((gnus-command-method (gnus-find-method-for-group group)))
 452     (cond
 453      ((and gnus-use-cache (numberp (car articles)))
 454       (gnus-cache-retrieve-headers articles group fetch-old))
 455      ((and gnus-agent (gnus-online gnus-command-method)
 456            (gnus-agent-method-p gnus-command-method))
 457       (gnus-agent-retrieve-headers articles group fetch-old))
 458      (t
 459       (funcall (gnus-get-function gnus-command-method 'retrieve-headers)
 460                articles (gnus-group-real-name group)
 461                (nth 1 gnus-command-method) fetch-old)))))
 462
 463 (defun gnus-retrieve-articles (articles group)
 464   "Request ARTICLES in GROUP."
 465   (let ((gnus-command-method (gnus-find-method-for-group group)))
 466     (funcall (gnus-get-function gnus-command-method 'retrieve-articles)
 467              articles (gnus-group-real-name group)
 468              (nth 1 gnus-command-method))))
 469
 470 (defun gnus-retrieve-groups (groups gnus-command-method)
 471   "Request active information on GROUPS from GNUS-COMMAND-METHOD."
 472   (when (stringp gnus-command-method)
 473     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 474   (funcall (gnus-get-function gnus-command-method 'retrieve-groups)
 475            groups (nth 1 gnus-command-method)))
 476
 477 (defun gnus-request-type (group &optional article)
 478   "Return the type (`post' or `mail') of GROUP (and ARTICLE)."
 479   (let ((gnus-command-method (gnus-find-method-for-group group)))
 480     (if (not (gnus-check-backend-function
 481               'request-type (car gnus-command-method)))
 482         'unknown
 483       (funcall (gnus-get-function gnus-command-method 'request-type)
 484                (gnus-group-real-name group) article))))
 485
 486 (defun gnus-request-update-group-status (group status)
 487   "Change the status of a group.
 488 Valid statuses include `subscribe' and `unsubscribe'."
 489   (let ((gnus-command-method (gnus-find-method-for-group group)))
 490     (if (not (gnus-check-backend-function
 491               'request-update-group-status (car gnus-command-method)))
 492         nil
 493       (funcall
 494        (gnus-get-function gnus-command-method 'request-update-group-status)
 495        (gnus-group-real-name group) status
 496        (nth 1 gnus-command-method)))))
 497
 498 (defun gnus-request-set-mark (group action)
 499   "Set marks on articles in the back end."
 500   (let ((gnus-command-method (gnus-find-method-for-group group)))
 501     (if (not (gnus-check-backend-function
 502               'request-set-mark (car gnus-command-method)))
 503         action
 504       (funcall (gnus-get-function gnus-command-method 'request-set-mark)
 505                (gnus-group-real-name group) action
 506                (nth 1 gnus-command-method))
 507       (gnus-run-hook-with-args gnus-after-set-mark-hook group action))))
 508
 509 (defun gnus-request-update-mark (group article mark)
 510   "Allow the back end to change the mark the user tries to put on an article."
 511   (let ((gnus-command-method (gnus-find-method-for-group group)))
 512     (if (not (gnus-check-backend-function
 513               'request-update-mark (car gnus-command-method)))
 514         mark
 515       (gnus-run-hook-with-args gnus-before-update-mark-hook group article mark)
 516       (funcall (gnus-get-function gnus-command-method 'request-update-mark)
 517                (gnus-group-real-name group) article mark))))
 518
 519 (defun gnus-request-article (article group &optional buffer)
 520   "Request the ARTICLE in GROUP.
 521 ARTICLE can either be an article number or an article Message-ID.
 522 If BUFFER, insert the article in that group."
 523   (let ((gnus-command-method (gnus-find-method-for-group group)))
 524     (funcall (gnus-get-function gnus-command-method 'request-article)
 525              article (gnus-group-real-name group)
 526              (nth 1 gnus-command-method) buffer)))
 527
 528 (defun gnus-request-thread (header group)
 529   "Request the headers in the thread containing the article specified by HEADER."
 530   (let ((gnus-command-method (gnus-find-method-for-group group)))
 531     (funcall (gnus-get-function gnus-command-method 'request-thread)
 532              header
 533              (gnus-group-real-name group))))
 534
 535 (defun gnus-select-group-with-message-id (group message-id)
 536   "Activate and select GROUP with the given MESSAGE-ID selected.
 537 Returns the article number of the message.
 538
 539 If GROUP is not already selected, the message will be the only one in
 540 the group's summary.
 541 "
 542   ;; TODO: is there a way to know at this point whether the group will
 543   ;; be newly-selected?  If so we could clean up the logic at the end
 544   ;;
 545   ;; save the new group's display parameter, if any, so we
 546   ;; can replace it temporarily with zero.
 547   (let ((saved-display
 548          (gnus-group-get-parameter group 'display :allow-list)))
 549
 550     ;; Tell gnus we really don't want any articles
 551     (gnus-group-set-parameter group 'display 0)
 552
 553     (unwind-protect
 554         (gnus-summary-read-group-1
 555          group (not :show-all) :no-article (not :kill-buffer)
 556          ;; The combination of no-display and this dummy list of
 557          ;; articles to select somehow makes it possible to open a
 558          ;; group with no articles in it.  Black magic.
 559          :no-display '(-1); select-articles
 560          )
 561       ;; Restore the new group's display parameter
 562       (gnus-group-set-parameter group 'display saved-display)))
 563
 564   ;; The summary buffer was suppressed by :no-display above.
 565   ;; Create it now and insert the message
 566   (let ((group-is-new (gnus-summary-setup-buffer group)))
 567     (condition-case err
 568         (let ((article-number
 569                (gnus-summary-insert-subject message-id)))
 570           (unless article-number
 571             (signal 'error "message-id not in group"))
 572           (gnus-summary-select-article nil nil nil article-number)
 573           article-number)
 574       ;; Clean up the new summary and propagate the error
 575       (error (when group-is-new (gnus-summary-exit))
 576              (apply 'signal err)))))
 577
 578 (defun gnus-simplify-group-name (group)
 579   "Return the simplest representation of the name of GROUP.
 580 This is the string that Gnus uses to identify the group."
 581   (gnus-group-prefixed-name
 582    (gnus-group-real-name group)
 583    (gnus-group-method group)))
 584
 585 (defun gnus-warp-to-article ()
 586   "Look up the current article in the group where it originated.
 587 This command only makes sense for groups shows articles gathered
 588 from other groups -- for instance, search results and the like."
 589   (interactive)
 590   (let ((gnus-command-method
 591          (gnus-find-method-for-group gnus-newsgroup-name)))
 592     (or
 593      (when (gnus-check-backend-function
 594             'warp-to-article (car gnus-command-method))
 595        (funcall (gnus-get-function gnus-command-method 'warp-to-article)))
 596      (and (bound-and-true-p gnus-registry-enabled)
 597           (gnus-try-warping-via-registry)))))
 598
 599 (defun gnus-request-head (article group)
 600   "Request the head of ARTICLE in GROUP."
 601   (let* ((gnus-command-method (gnus-find-method-for-group group))
 602          (head (gnus-get-function gnus-command-method 'request-head t))
 603          res clean-up)
 604     (cond
 605      ;; Check the cache.
 606      ((and gnus-use-cache
 607            (numberp article)
 608            (gnus-cache-request-article article group))
 609       (setq res (cons group article)
 610             clean-up t))
 611      ;; Check the agent cache.
 612      ((gnus-agent-request-article article group)
 613       (setq res (cons group article)
 614             clean-up t))
 615      ;; Use `head' function.
 616      ((fboundp head)
 617       (setq res (funcall head article
 618                          (and (not gnus-override-method) (gnus-group-real-name group))
 619                          (nth 1 gnus-command-method))))
 620      ;; Use `article' function.
 621      (t
 622       (setq res (gnus-request-article article group)
 623             clean-up t)))
 624     (when clean-up
 625       (with-current-buffer nntp-server-buffer
 626         (goto-char (point-min))
 627         (when (search-forward "\n\n" nil t)
 628           (delete-region (1- (point)) (point-max)))
 629         (nnheader-fold-continuation-lines)))
 630     res))
 631
 632 (defun gnus-request-body (article group)
 633   "Request the body of ARTICLE in GROUP."
 634   (let* ((gnus-command-method (gnus-find-method-for-group group))
 635          (head (gnus-get-function gnus-command-method 'request-body t))
 636          res clean-up)
 637     (cond
 638      ;; Check the cache.
 639      ((and gnus-use-cache
 640            (numberp article)
 641            (gnus-cache-request-article article group))
 642       (setq res (cons group article)
 643             clean-up t))
 644      ;; Check the agent cache.
 645      ((gnus-agent-request-article article group)
 646       (setq res (cons group article)
 647             clean-up t))
 648      ;; Use `head' function.
 649      ((fboundp head)
 650       (setq res (funcall head article (gnus-group-real-name group)
 651                          (nth 1 gnus-command-method))))
 652      ;; Use `article' function.
 653      (t
 654       (setq res (gnus-request-article article group)
 655             clean-up t)))
 656     (when clean-up
 657       (with-current-buffer nntp-server-buffer
 658         (goto-char (point-min))
 659         (when (search-forward "\n\n" nil t)
 660           (delete-region (point-min) (1- (point))))))
 661     res))
 662
 663 (defun gnus-request-post (gnus-command-method)
 664   "Post the current buffer using GNUS-COMMAND-METHOD."
 665   (when (stringp gnus-command-method)
 666     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 667   (funcall (gnus-get-function gnus-command-method 'request-post)
 668            (nth 1 gnus-command-method)))
 669
 670 (defun gnus-request-expunge-group (group gnus-command-method)
 671   "Expunge GROUP, which is removing articles that have been marked as deleted."
 672   (when (stringp gnus-command-method)
 673     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 674   (funcall (gnus-get-function gnus-command-method 'request-expunge-group)
 675            (gnus-group-real-name group)
 676            (nth 1 gnus-command-method)))
 677
 678 (defun gnus-request-scan (group gnus-command-method)
 679   "Request a SCAN being performed in GROUP from GNUS-COMMAND-METHOD.
 680 If GROUP is nil, all groups on GNUS-COMMAND-METHOD are scanned."
 681   (let ((gnus-command-method
 682          (if group (gnus-find-method-for-group group) gnus-command-method))
 683         (gnus-inhibit-demon t)
 684         (mail-source-plugged gnus-plugged))
 685     (when (or gnus-plugged
 686               (not (gnus-agent-method-p gnus-command-method)))
 687       (setq gnus-internal-registry-spool-current-method gnus-command-method)
 688       (funcall (gnus-get-function gnus-command-method 'request-scan)
 689                (and group (gnus-group-real-name group))
 690                (nth 1 gnus-command-method)))))
 691
 692 (defun gnus-request-update-info (info gnus-command-method)
 693   (when (gnus-check-backend-function
 694          'request-update-info (car gnus-command-method))
 695     (when (stringp gnus-command-method)
 696       (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 697     (funcall (gnus-get-function gnus-command-method 'request-update-info)
 698              (gnus-group-real-name (gnus-info-group info)) info
 699              (nth 1 gnus-command-method))))
 700
 701 (defsubst gnus-request-marks (info gnus-command-method)
 702   "Request that GNUS-COMMAND-METHOD update INFO."
 703   (when (stringp gnus-command-method)
 704     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 705   (when (gnus-check-backend-function
 706          'request-marks (car gnus-command-method))
 707     (let ((group (gnus-info-group info)))
 708       (and (funcall (gnus-get-function gnus-command-method 'request-marks)
 709                     (gnus-group-real-name group)
 710                     info (nth 1 gnus-command-method))
 711            ;; If the minimum article number is greater than 1, then all
 712            ;; smaller article numbers are known not to exist; we'll
 713            ;; artificially add those to the 'read range.
 714            (let* ((active (gnus-active group))
 715                   (min (car active)))
 716              (when (> min 1)
 717                (let* ((range (if (= min 2) 1 (cons 1 (1- min))))
 718                       (read (gnus-info-read info))
 719                       (new-read (gnus-range-add read (list range))))
 720                  (gnus-info-set-read info new-read)))
 721              info)))))
 722
 723 (defun gnus-request-expire-articles (articles group &optional force)
 724   (let* ((gnus-command-method (gnus-find-method-for-group group))
 725          ;; Filter out any negative article numbers; they can't be
 726          ;; expired here.
 727          (articles
 728           (delq nil (mapcar (lambda (n) (and (>= n 0) n)) articles)))
 729          (gnus-inhibit-demon t)
 730          (not-deleted
 731           (funcall
 732            (gnus-get-function gnus-command-method 'request-expire-articles)
 733            articles (gnus-group-real-name group) (nth 1 gnus-command-method)
 734            force)))
 735     (when (and gnus-agent
 736                (gnus-agent-method-p gnus-command-method))
 737       (let ((expired-articles (gnus-sorted-difference articles not-deleted)))
 738         (when expired-articles
 739           (gnus-agent-expire expired-articles group 'force))))
 740     not-deleted))
 741
 742 (defun gnus-request-move-article (article group server accept-function
 743                                           &optional last move-is-internal)
 744   (let* ((gnus-command-method (gnus-find-method-for-group group))
 745          (result (funcall (gnus-get-function gnus-command-method
 746                                              'request-move-article)
 747                           article (gnus-group-real-name group)
 748                           (nth 1 gnus-command-method) accept-function
 749                           last move-is-internal)))
 750     (when (and result gnus-agent
 751                (gnus-agent-method-p gnus-command-method))
 752       (gnus-agent-unfetch-articles group (list article)))
 753     result))
 754
 755 (defun gnus-request-accept-article (group &optional gnus-command-method last
 756                                           no-encode)
 757   ;; Make sure there's a newline at the end of the article.
 758   (when (stringp gnus-command-method)
 759     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 760   (when (and (not gnus-command-method)
 761              (stringp group))
 762     (setq gnus-command-method (or (gnus-find-method-for-group group)
 763                                   (gnus-group-name-to-method group))))
 764   (goto-char (point-max))
 765   (unless (bolp)
 766     (insert "\n"))
 767   (unless no-encode
 768     (let ((message-options message-options))
 769       (message-options-set-recipient)
 770       (save-restriction
 771         (message-narrow-to-head)
 772         (let ((mail-parse-charset message-default-charset))
 773           (mail-encode-encoded-word-buffer)))
 774       (message-encode-message-body)))
 775   (let ((gnus-command-method (or gnus-command-method
 776                                  (gnus-find-method-for-group group)))
 777         (result
 778          (funcall
 779           (gnus-get-function gnus-command-method 'request-accept-article)
 780           (if (stringp group) (gnus-group-real-name group) group)
 781           (cadr gnus-command-method)
 782           last)))
 783     (when (and gnus-agent
 784                (gnus-agent-method-p gnus-command-method)
 785                (cdr result))
 786       (gnus-agent-regenerate-group group (list (cdr result))))
 787     result))
 788
 789 (defun gnus-request-replace-article (article group buffer &optional no-encode)
 790   (unless no-encode
 791     (let ((message-options message-options))
 792       (message-options-set-recipient)
 793       (save-restriction
 794         (message-narrow-to-head)
 795         (let ((mail-parse-charset message-default-charset))
 796           (mail-encode-encoded-word-buffer)))
 797       (message-encode-message-body)))
 798   (let* ((func (car (gnus-group-name-to-method group)))
 799          (result (funcall (intern (format "%s-request-replace-article" func))
 800                           article (gnus-group-real-name group) buffer)))
 801     (when (and gnus-agent (gnus-agent-method-p gnus-command-method))
 802       (gnus-agent-regenerate-group group (list article)))
 803     result))
 804
 805 (defun gnus-request-restore-buffer (article group)
 806   "Request a new buffer restored to the state of ARTICLE."
 807   (let ((gnus-command-method (gnus-find-method-for-group group)))
 808     (funcall (gnus-get-function gnus-command-method 'request-restore-buffer)
 809              article (gnus-group-real-name group)
 810              (nth 1 gnus-command-method))))
 811
 812 (defun gnus-request-create-group (group &optional gnus-command-method args)
 813   (when (stringp gnus-command-method)
 814     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 815   (let ((gnus-command-method
 816          (or gnus-command-method (gnus-find-method-for-group group))))
 817     (funcall (gnus-get-function gnus-command-method 'request-create-group)
 818              (gnus-group-real-name group) (nth 1 gnus-command-method) args)))
 819
 820 (defun gnus-request-delete-group (group &optional force)
 821   (let* ((gnus-command-method (gnus-find-method-for-group group))
 822          (result
 823           (funcall (gnus-get-function gnus-command-method 'request-delete-group)
 824                    (gnus-group-real-name group) force (nth 1 gnus-command-method))))
 825     (when result
 826       (gnus-cache-delete-group group)
 827       (gnus-agent-delete-group group))
 828     result))
 829
 830 (defun gnus-request-rename-group (group new-name)
 831   (let* ((gnus-command-method (gnus-find-method-for-group group))
 832          (result
 833           (funcall (gnus-get-function gnus-command-method 'request-rename-group)
 834                    (gnus-group-real-name group)
 835                    (gnus-group-real-name new-name) (nth 1 gnus-command-method))))
 836     (when result
 837       (gnus-cache-rename-group group new-name)
 838       (gnus-agent-rename-group group new-name))
 839     result))
 840
 841 (defun gnus-close-backends ()
 842   ;; Send a close request to all backends that support such a request.
 843   (let ((methods gnus-valid-select-methods)
 844         (gnus-inhibit-demon t)
 845         func gnus-command-method)
 846     (while (setq gnus-command-method (pop methods))
 847       (when (fboundp (setq func (intern
 848                                  (concat (car gnus-command-method)
 849                                          "-request-close"))))
 850         (funcall func)))))
 851
 852 (defun gnus-asynchronous-p (gnus-command-method)
 853   (let ((func (gnus-get-function gnus-command-method 'asynchronous-p t)))
 854     (when (fboundp func)
 855       (funcall func))))
 856
 857 (defun gnus-remove-denial (gnus-command-method)
 858   (when (stringp gnus-command-method)
 859     (setq gnus-command-method (gnus-server-to-method gnus-command-method)))
 860   (let* ((elem (assoc gnus-command-method gnus-opened-servers))
 861          (status (cadr elem)))
 862     ;; If this hasn't been opened before, we add it to the list.
 863     (when (eq status 'denied)
 864       ;; Set the status of this server.
 865       (setcar (cdr elem) 'closed))))
 866
 867 (provide 'gnus-int)
 868
 869 ;;; gnus-int.el ends here