1 ;;; gnus-bcklg.el --- backlog functions for Gnus
2 ;; Copyright (C) 1996,97,98 Free Software Foundation, Inc.
4 ;; Author: Lars Magne Ingebrigtsen <larsi@ifi.uio.no>
7 ;; This file is part of GNU Emacs.
9 ;; GNU Emacs is free software; you can redistribute it and/or modify
10 ;; it under the terms of the GNU General Public License as published by
11 ;; the Free Software Foundation; either version 2, or (at your option)
14 ;; GNU Emacs is distributed in the hope that it will be useful,
15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 ;; GNU General Public License for more details.
19 ;; You should have received a copy of the GNU General Public License
20 ;; along with GNU Emacs; see the file COPYING. If not, write to the
21 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
22 ;; Boston, MA 02111-1307, USA.
28 (eval-when-compile (require 'cl))
33 ;;; Buffering of read articles.
36 (defvar gnus-backlog-buffer " *Gnus Backlog*")
37 (defvar gnus-backlog-articles nil)
38 (defvar gnus-backlog-hashtb nil)
40 (defun gnus-backlog-buffer ()
41 "Return the backlog buffer."
42 (or (get-buffer gnus-backlog-buffer)
44 (set-buffer (get-buffer-create gnus-backlog-buffer))
45 (buffer-disable-undo (current-buffer))
46 (setq buffer-read-only t)
47 (gnus-add-current-to-buffer-list)
48 (get-buffer gnus-backlog-buffer))))
50 (defun gnus-backlog-setup ()
51 "Initialize backlog variables."
52 (unless gnus-backlog-hashtb
53 (setq gnus-backlog-hashtb (gnus-make-hashtable 1024))))
55 (gnus-add-shutdown 'gnus-backlog-shutdown 'gnus)
57 (defun gnus-backlog-shutdown ()
58 "Clear all backlog variables and buffers."
59 (when (get-buffer gnus-backlog-buffer)
60 (kill-buffer gnus-backlog-buffer))
61 (setq gnus-backlog-hashtb nil
62 gnus-backlog-articles nil))
64 (defun gnus-backlog-enter-article (group number buffer)
66 (let ((ident (intern (concat group ":" (int-to-string number))
69 (if (memq ident gnus-backlog-articles)
70 () ; It's already kept.
71 ;; Remove the oldest article, if necessary.
72 (and (numberp gnus-keep-backlog)
73 (>= (length gnus-backlog-articles) gnus-keep-backlog)
74 (gnus-backlog-remove-oldest-article))
75 (push ident gnus-backlog-articles)
76 ;; Insert the new article.
78 (set-buffer (gnus-backlog-buffer))
79 (let (buffer-read-only)
80 (goto-char (point-max))
84 (insert-buffer-substring buffer)
85 ;; Tag the beginning of the article with the ident.
86 (gnus-put-text-property b (1+ b) 'gnus-backlog ident))))))
88 (defun gnus-backlog-remove-oldest-article ()
90 (set-buffer (gnus-backlog-buffer))
91 (goto-char (point-min))
92 (if (zerop (buffer-size))
93 () ; The buffer is empty.
94 (let ((ident (get-text-property (point) 'gnus-backlog))
96 ;; Remove the ident from the list of articles.
98 (setq gnus-backlog-articles (delq ident gnus-backlog-articles)))
99 ;; Delete the article itself.
101 (point) (next-single-property-change
102 (1+ (point)) 'gnus-backlog nil (point-max)))))))
104 (defun gnus-backlog-remove-article (group number)
105 "Remove article NUMBER in GROUP from the backlog."
106 (when (numberp number)
108 (let ((ident (intern (concat group ":" (int-to-string number))
109 gnus-backlog-hashtb))
111 (when (memq ident gnus-backlog-articles)
112 ;; It was in the backlog.
114 (set-buffer (gnus-backlog-buffer))
115 (let (buffer-read-only)
116 (when (setq beg (text-property-any
117 (point-min) (point-max) 'gnus-backlog
119 ;; Find the end (i. e., the beginning of the next article).
121 (next-single-property-change
122 (1+ beg) 'gnus-backlog (current-buffer) (point-max)))
123 (delete-region beg end)
126 (setq gnus-backlog-articles (delq ident gnus-backlog-articles)))))))
128 (defun gnus-backlog-request-article (group number buffer)
129 (when (numberp number)
131 (let ((ident (intern (concat group ":" (int-to-string number))
132 gnus-backlog-hashtb))
134 (when (memq ident gnus-backlog-articles)
135 ;; It was in the backlog.
137 (set-buffer (gnus-backlog-buffer))
138 (if (not (setq beg (text-property-any
139 (point-min) (point-max) 'gnus-backlog
141 ;; It wasn't in the backlog after all.
143 (setq gnus-backlog-articles (delq ident gnus-backlog-articles)))
144 ;; Find the end (i. e., the beginning of the next article).
146 (next-single-property-change
147 (1+ beg) 'gnus-backlog (current-buffer) (point-max)))))
148 (let ((buffer-read-only nil))
150 (insert-buffer-substring gnus-backlog-buffer beg end)
153 (provide 'gnus-bcklg)
155 ;;; gnus-bcklg.el ends here