lisp/gnus/nnagent.el

   1 ;;; nnagent.el --- offline backend for Gnus
   2
   3 ;; Copyright (C) 1997-2011 Free Software Foundation, Inc.
   4
   5 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
   6 ;; Keywords: news, mail
   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 (require 'nnheader)
  28 (require 'nnoo)
  29 (eval-when-compile (require 'cl))
  30 (require 'gnus-agent)
  31 (require 'nnml)
  32
  33 (nnoo-declare nnagent
  34   nnml)
  35
  36 \f
  37
  38 (defconst nnagent-version "nnagent 1.0")
  39
  40 (defvoo nnagent-directory nil
  41   "Internal variable."
  42   nnml-directory)
  43
  44 (defvoo nnagent-active-file nil
  45   "Internal variable."
  46   nnml-active-file)
  47
  48 (defvoo nnagent-newsgroups-file nil
  49   "Internal variable."
  50   nnml-newsgroups-file)
  51
  52 (defvoo nnagent-get-new-mail nil
  53   "Internal variable."
  54   nnml-get-new-mail)
  55
  56 ;;; Interface functions.
  57
  58 (nnoo-define-basics nnagent)
  59
  60 (defun nnagent-server (server)
  61   (and server (format "%s+%s" (car gnus-command-method) server)))
  62
  63 (deffoo nnagent-open-server (server &optional defs)
  64   (setq defs
  65         `((nnagent-directory ,(gnus-agent-directory))
  66           (nnagent-active-file ,(gnus-agent-lib-file "active"))
  67           (nnagent-newsgroups-file ,(gnus-agent-lib-file "newsgroups"))
  68           (nnagent-get-new-mail nil)))
  69   (nnoo-change-server 'nnagent
  70                       (nnagent-server server)
  71                       defs)
  72   (let ((dir (gnus-agent-directory))
  73         err)
  74     (cond
  75      ((not (condition-case arg
  76                (file-exists-p dir)
  77              (ftp-error (setq err (format "%s" arg)))))
  78       (nnagent-close-server)
  79       (nnheader-report
  80        'nnagent (or err
  81                     (format "No such file or directory: %s" dir))))
  82      ((not (file-directory-p (file-truename dir)))
  83       (nnagent-close-server)
  84       (nnheader-report 'nnagent "Not a directory: %s" dir))
  85      (t
  86       (nnheader-report 'nnagent "Opened server %s using directory %s"
  87                        server dir)
  88       t))))
  89
  90 (deffoo nnagent-retrieve-groups (groups &optional server)
  91   (save-excursion
  92     (cond
  93      ((file-exists-p (gnus-agent-lib-file "groups"))
  94       (nnmail-find-file (gnus-agent-lib-file "groups"))
  95       'groups)
  96      ((file-exists-p (gnus-agent-lib-file "active"))
  97       (nnmail-find-file (gnus-agent-lib-file "active"))
  98       'active)
  99      (t nil))))
 100
 101 (defun nnagent-request-type (group article)
 102   (unless (stringp article)
 103     (let ((gnus-agent nil))
 104       (if (not (gnus-check-backend-function
 105                 'request-type (car gnus-command-method)))
 106           'unknown
 107         (funcall (gnus-get-function gnus-command-method 'request-type)
 108                  (gnus-group-real-name group) article)))))
 109
 110 (deffoo nnagent-request-newgroups (date server)
 111   nil)
 112
 113 (deffoo nnagent-request-update-info (group info &optional server)
 114   nil)
 115
 116 (deffoo nnagent-request-post (&optional server)
 117   (gnus-agent-insert-meta-information 'news gnus-command-method)
 118   (gnus-request-accept-article "nndraft:queue" nil t t))
 119
 120 (deffoo nnagent-request-set-mark (group action server)
 121   (mm-with-unibyte-buffer
 122     (insert "(gnus-agent-synchronize-group-flags \""
 123             group
 124             "\" '")
 125     (gnus-pp action)
 126     (insert " \""
 127             (gnus-method-to-server gnus-command-method)
 128             "\"")
 129     (insert ")\n")
 130     (let ((coding-system-for-write nnheader-file-coding-system))
 131       (write-region (point-min) (point-max) (gnus-agent-lib-file "flags")
 132                     t 'silent)))
 133   ;; Also set the marks for the original back end that keeps marks in
 134   ;; the local system.
 135   (let ((gnus-agent nil))
 136     (when (and (memq (car gnus-command-method) '(nntp))
 137                (gnus-check-backend-function 'request-set-mark
 138                                             (car gnus-command-method)))
 139       (funcall (gnus-get-function gnus-command-method 'request-set-mark)
 140                group action server)))
 141   nil)
 142
 143 (deffoo nnagent-retrieve-headers (articles &optional group server fetch-old)
 144   (let ((file (gnus-agent-article-name ".overview" group))
 145         arts n first)
 146     (save-excursion
 147       (gnus-agent-load-alist group)
 148       (setq arts (gnus-sorted-difference
 149                   articles (mapcar 'car gnus-agent-article-alist)))
 150       ;; Assume that articles with smaller numbers than the first one
 151       ;; Agent knows are gone.
 152       (setq first (caar gnus-agent-article-alist))
 153       (when first
 154         (while (and arts (< (car arts) first))
 155           (pop arts)))
 156       (set-buffer nntp-server-buffer)
 157       (erase-buffer)
 158       (let ((file-name-coding-system nnmail-pathname-coding-system))
 159         (nnheader-insert-nov-file file (car articles)))
 160       (goto-char (point-min))
 161       (gnus-parse-without-error
 162         (while (and arts (not (eobp)))
 163           (setq n (read (current-buffer)))
 164           (when (> n (car arts))
 165             (beginning-of-line))
 166           (while (and arts (> n (car arts)))
 167             (insert (format
 168                      "%d\t[Undownloaded article %d]\tGnus Agent\t\t\t\n"
 169                      (car arts) (car arts)))
 170             (pop arts))
 171           (when (and arts (= n (car arts)))
 172             (pop arts))
 173           (forward-line 1)))
 174       (while arts
 175         (insert (format
 176                  "%d\t[Undownloaded article %d]\tGnus Agent\t\t\t\n"
 177                  (car arts) (car arts)))
 178         (pop arts))
 179       (if (and fetch-old
 180                (not (numberp fetch-old)))
 181           t                             ; Don't remove anything.
 182         (nnheader-nov-delete-outside-range
 183          (if fetch-old (max 1 (- (car articles) fetch-old))
 184            (car articles))
 185          (car (last articles)))
 186         t)
 187       'nov)))
 188
 189 (deffoo nnagent-request-expire-articles (articles group &optional server force)
 190   articles)
 191
 192 (deffoo nnagent-request-group (group &optional server dont-check info)
 193   (nnoo-parent-function 'nnagent 'nnml-request-group
 194                         (list group (nnagent-server server) dont-check info)))
 195
 196 (deffoo nnagent-close-group (group &optional server)
 197   (nnoo-parent-function 'nnagent 'nnml-close-group
 198                         (list group (nnagent-server server))))
 199
 200 (deffoo nnagent-request-accept-article (group &optional server last)
 201   (nnoo-parent-function 'nnagent 'nnml-request-accept-article
 202                         (list group (nnagent-server server) last)))
 203
 204 (deffoo nnagent-request-article (id &optional group server buffer)
 205   (nnoo-parent-function 'nnagent 'nnml-request-article
 206                         (list id group (nnagent-server server) buffer)))
 207
 208 (deffoo nnagent-request-create-group (group &optional server args)
 209   (nnoo-parent-function 'nnagent 'nnml-request-create-group
 210                         (list group (nnagent-server server) args)))
 211
 212 (deffoo nnagent-request-delete-group (group &optional force server)
 213   (nnoo-parent-function 'nnagent 'nnml-request-delete-group
 214                         (list group force (nnagent-server server))))
 215
 216 (deffoo nnagent-request-list (&optional server)
 217   (nnoo-parent-function 'nnagent 'nnml-request-list
 218                         (list (nnagent-server server))))
 219
 220 (deffoo nnagent-request-list-newsgroups (&optional server)
 221   (nnoo-parent-function 'nnagent 'nnml-request-list-newsgroups
 222                         (list (nnagent-server server))))
 223
 224 (deffoo nnagent-request-move-article
 225     (article group server accept-form &optional last move-is-internal)
 226   (nnoo-parent-function 'nnagent 'nnml-request-move-article
 227                         (list article group (nnagent-server server)
 228                               accept-form last move-is-internal)))
 229
 230 (deffoo nnagent-request-rename-group (group new-name &optional server)
 231   (nnoo-parent-function 'nnagent 'nnml-request-rename-group
 232                         (list group new-name (nnagent-server server))))
 233
 234 (deffoo nnagent-request-scan (&optional group server)
 235   (nnoo-parent-function 'nnagent 'nnml-request-scan
 236                         (list group (nnagent-server server))))
 237
 238 (deffoo nnagent-set-status (article name value &optional group server)
 239   (nnoo-parent-function 'nnagent 'nnml-set-status
 240                         (list article name value group (nnagent-server server))))
 241
 242 (deffoo nnagent-server-opened (&optional server)
 243   (nnoo-parent-function 'nnagent 'nnml-server-opened
 244                         (list (nnagent-server server))))
 245
 246 (deffoo nnagent-status-message (&optional server)
 247   (nnoo-parent-function 'nnagent 'nnml-status-message
 248                         (list (nnagent-server server))))
 249
 250 (deffoo nnagent-request-regenerate (server)
 251   (nnoo-parent-function 'nnagent 'nnml-request-regenerate
 252                         (list (nnagent-server server))))
 253
 254 (deffoo nnagent-retrieve-group-data-early (server infos)
 255   nil)
 256
 257 ;; Use nnml functions for just about everything.
 258 (nnoo-import nnagent
 259   (nnml))
 260
 261 \f
 262 ;;; Internal functions.
 263
 264 (provide 'nnagent)
 265
 266 ;;; nnagent.el ends here