Add lisp/gnus/nnregistry.el.

lisp/gnus/nnregistry.el

@@ -0,0 +1,65 @@
+;;; nnregistry.el --- access to articles via Gnus' message-id registry
+;;; -*- coding: utf-8 -*-
+
+;; Copyright (C) 2010 Free Software Foundation, Inc.
+
+;; Authors: Ludovic Courtès <ludo@gnu.org>
+;; Keywords: news, mail
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; This file provides the `nnregistry' Gnus back-end.  It can be used
+;; in `gnus-refer-article-method' to quickly search for a message by
+;; id, regardless of the back-end that stores it.
+
+;;; Code:
+
+(require 'nnoo)
+(require 'gnus-registry)
+(require 'gnus-int)
+
+(nnoo-declare nnregistry)
+
+(deffoo nnregistry-server-opened (server)
+  (eq gnus-registry-install t))
+
+(deffoo nnregistry-close-server (server)
+  t)
+
+(deffoo nnregistry-status-message (server)
+  nil)
+
+(deffoo nnregistry-open-server (server &optional defs)
+  (eq gnus-registry-install t))
+
+(defvar nnregistry-within-nnregistry nil)
+
+(deffoo nnregistry-request-article (id &optional group server buffer)
+  (and (not nnregistry-within-nnregistry)
+       (let* ((nnregistry-within-nnregistry t)
+	      (group (gnus-registry-fetch-group id))
+	      (gnus-override-method nil))
+	 (message "nnregistry: requesting article `%s' in group `%s'"
+		  id group)
+	 (and group
+	      (gnus-check-group group)
+	      (gnus-request-article id group buffer)))))
+
+(provide 'nnregistry)
+
+;;; nnregistry.el ends here