1 ;;; gnus-bcklg.el --- backlog functions for Gnus
2 ;; Copyright (C) 1996,97,98,99 Free Software Foundation, Inc.
4 ;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
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 (gnus-get-buffer-create gnus-backlog-buffer))
46 (setq buffer-read-only t)
47 (get-buffer gnus-backlog-buffer))))
49 (defun gnus-backlog-setup ()
50 "Initialize backlog variables."
51 (unless gnus-backlog-hashtb
52 (setq gnus-backlog-hashtb (gnus-make-hashtable 1024))))
54 (gnus-add-shutdown 'gnus-backlog-shutdown 'gnus)
56 (defun gnus-backlog-shutdown ()
57 "Clear all backlog variables and buffers."
58 (when (get-buffer gnus-backlog-buffer)
59 (kill-buffer gnus-backlog-buffer))
60 (setq gnus-backlog-hashtb nil
61 gnus-backlog-articles nil))
63 (defun gnus-backlog-enter-article (group number buffer)
65 (let ((ident (intern (concat group ":" (int-to-string number))
68 (if (memq ident gnus-backlog-articles)
69 () ; It's already kept.
70 ;; Remove the oldest article, if necessary.
71 (and (numberp gnus-keep-backlog)
72 (>= (length gnus-backlog-articles) gnus-keep-backlog)
73 (gnus-backlog-remove-oldest-article))
74 (push ident gnus-backlog-articles)
75 ;; Insert the new article.
77 (set-buffer (gnus-backlog-buffer))
78 (let (buffer-read-only)
79 (goto-char (point-max))
83 (insert-buffer-substring buffer)
84 ;; Tag the beginning of the article with the ident.
85 (gnus-put-text-property b (1+ b) 'gnus-backlog ident))))))
87 (defun gnus-backlog-remove-oldest-article ()
89 (set-buffer (gnus-backlog-buffer))
90 (goto-char (point-min))
91 (if (zerop (buffer-size))
92 () ; The buffer is empty.
93 (let ((ident (get-text-property (point) 'gnus-backlog))
95 ;; Remove the ident from the list of articles.
97 (setq gnus-backlog-articles (delq ident gnus-backlog-articles)))
98 ;; Delete the article itself.
100 (point) (next-single-property-change
101 (1+ (point)) 'gnus-backlog nil (point-max)))))))
103 (defun gnus-backlog-remove-article (group number)
104 "Remove article NUMBER in GROUP from the backlog."
105 (when (numberp number)
107 (let ((ident (intern (concat group ":" (int-to-string number))
108 gnus-backlog-hashtb))
110 (when (memq ident gnus-backlog-articles)
111 ;; It was in the backlog.
113 (set-buffer (gnus-backlog-buffer))
114 (let (buffer-read-only)
115 (when (setq beg (text-property-any
116 (point-min) (point-max) 'gnus-backlog
118 ;; Find the end (i. e., the beginning of the next article).
120 (next-single-property-change
121 (1+ beg) 'gnus-backlog (current-buffer) (point-max)))
122 (delete-region beg end)
125 (setq gnus-backlog-articles (delq ident gnus-backlog-articles)))))))
127 (defun gnus-backlog-request-article (group number buffer)
128 (when (numberp number)
130 (let ((ident (intern (concat group ":" (int-to-string number))
131 gnus-backlog-hashtb))
133 (when (memq ident gnus-backlog-articles)
134 ;; It was in the backlog.
136 (set-buffer (gnus-backlog-buffer))
137 (if (not (setq beg (text-property-any
138 (point-min) (point-max) 'gnus-backlog
140 ;; It wasn't in the backlog after all.
142 (setq gnus-backlog-articles (delq ident gnus-backlog-articles)))
143 ;; Find the end (i. e., the beginning of the next article).
145 (next-single-property-change
146 (1+ beg) 'gnus-backlog (current-buffer) (point-max)))))
147 (let ((buffer-read-only nil))
149 (insert-buffer-substring gnus-backlog-buffer beg end)
152 (provide 'gnus-bcklg)
154 ;;; gnus-bcklg.el ends here