1 ;;; gnus-demon.el --- daemonic Gnus behaviour
2 ;; Copyright (C) 1995,96 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.
33 (if (string-match "XEmacs" (emacs-version))
37 (defvar gnus-demon-handlers nil
38 "Alist of daemonic handlers to be run at intervals.
39 Each handler is a list on the form
43 FUNCTION is the function to be called.
44 TIME is the number of `gnus-demon-timestep's between each call.
45 If nil, never call. If t, call each `gnus-demon-timestep'.
46 If IDLE is t, only call if Emacs has been idle for a while. If IDLE
47 is a number, only call when Emacs has been idle more than this number
48 of `gnus-demon-timestep's. If IDLE is nil, don't care about
49 idleness. If IDLE is a number and TIME is nil, then call once each
50 time Emacs has been idle for IDLE `gnus-demon-timestep's.")
52 (defvar gnus-demon-timestep 60
53 "*Number of seconds in each demon timestep.")
55 ;;; Internal variables.
57 (defvar gnus-demon-timer nil)
58 (defvar gnus-demon-idle-has-been-called nil)
59 (defvar gnus-demon-idle-time 0)
60 (defvar gnus-demon-handler-state nil)
61 (defvar gnus-demon-is-idle nil)
62 (defvar gnus-demon-last-keys nil)
65 (autoload 'timezone-parse-date "timezone")
66 (autoload 'timezone-make-arpa-date "timezone"))
70 (defun gnus-demon-add-handler (function time idle)
71 "Add the handler FUNCTION to be run at TIME and IDLE."
72 ;; First remove any old handlers that use this function.
73 (gnus-demon-remove-handler function)
74 ;; Then add the new one.
75 (push (list function time idle) gnus-demon-handlers)
78 (defun gnus-demon-remove-handler (function &optional no-init)
79 "Remove the handler FUNCTION from the list of handlers."
80 (setq gnus-demon-handlers
81 (delq (assq function gnus-demon-handlers)
83 (or no-init (gnus-demon-init)))
85 (defun gnus-demon-init ()
86 "Initialize the Gnus daemon."
89 (if (null gnus-demon-handlers)
92 (setq gnus-demon-timer
94 gnus-demon-timestep gnus-demon-timestep 'gnus-demon))
95 ;; Reset control variables.
96 (setq gnus-demon-handler-state
99 (list (car handler) (gnus-demon-time-to-step (nth 1 handler))
101 gnus-demon-handlers))
102 (setq gnus-demon-idle-time 0)
103 (setq gnus-demon-idle-has-been-called nil)
104 (setq gnus-use-demon t)))
106 (gnus-add-shutdown 'gnus-demon-cancel 'gnus)
108 (defun gnus-demon-cancel ()
109 "Cancel any Gnus daemons."
111 (and gnus-demon-timer
112 (nnheader-cancel-timer gnus-demon-timer))
113 (setq gnus-demon-timer nil
115 (nnheader-cancel-function-timers 'gnus-demon))
117 (defun gnus-demon-is-idle-p ()
118 "Whether Emacs is idle or not."
119 ;; We do this simply by comparing the 100 most recent keystrokes
120 ;; with the ones we had last time. If they are the same, one might
121 ;; guess that Emacs is indeed idle. This only makes sense if one
122 ;; calls this function seldom -- like once a minute, which is what
124 (let ((keys (recent-keys)))
125 (or (equal keys gnus-demon-last-keys)
127 (setq gnus-demon-last-keys keys)
130 (defun gnus-demon-time-to-step (time)
131 "Find out how many seconds to TIME, which is on the form \"17:43\"."
132 (if (not (stringp time))
134 (let* ((date (current-time-string))
135 (dv (timezone-parse-date date))
136 (tdate (timezone-make-arpa-date
137 (string-to-number (aref dv 0))
138 (string-to-number (aref dv 1))
139 (string-to-number (aref dv 2)) time
140 (or (aref dv 4) "UT")))
141 (nseconds (gnus-time-minus
142 (gnus-encode-date tdate) (gnus-encode-date date))))
144 (/ (if (< nseconds 0)
145 (+ nseconds (* 60 60 24))
146 nseconds) gnus-demon-timestep)))))
149 "The Gnus daemon that takes care of running all Gnus handlers."
150 ;; Increase or reset the time Emacs has been idle.
151 (if (gnus-demon-is-idle-p)
152 (incf gnus-demon-idle-time)
153 (setq gnus-demon-idle-time 0)
154 (setq gnus-demon-idle-has-been-called nil))
155 ;; Then we go through all the handler and call those that are
156 ;; sufficiently ripe.
157 (let ((handlers gnus-demon-handler-state)
160 (setq handler (pop handlers))
162 ((numberp (setq time (nth 1 handler)))
163 ;; These handlers use a regular timeout mechanism. We decrease
164 ;; the timer if it hasn't reached zero yet.
166 (setcar (nthcdr 1 handler) (decf time)))
167 (and (zerop time) ; If the timer now is zero...
168 (or (not (setq idle (nth 2 handler))) ; Don't care about idle.
169 (and (numberp idle) ; Numerical idle...
170 (< idle gnus-demon-idle-time)) ; Idle timed out.
171 gnus-demon-is-idle) ; Or just need to be idle.
172 ;; So we call the handler.
174 (funcall (car handler))
175 ;; And reset the timer.
176 (setcar (nthcdr 1 handler)
177 (gnus-demon-time-to-step
178 (nth 1 (assq (car handler) gnus-demon-handlers)))))))
179 ;; These are only supposed to be called when Emacs is idle.
180 ((null (setq idle (nth 2 handler)))
183 ((not (numberp idle))
184 ;; We want to call this handler each and every time that
186 (funcall (car handler)))
188 ;; We want to call this handler only if Emacs has been idle
189 ;; for a specified number of timesteps.
190 (and (not (memq (car handler) gnus-demon-idle-has-been-called))
191 (< idle gnus-demon-idle-time)
193 (funcall (car handler))
194 ;; Make sure the handler won't be called once more in
196 (push (car handler) gnus-demon-idle-has-been-called))))))))
198 (defun gnus-demon-add-nocem ()
199 "Add daemonic NoCeM handling to Gnus."
200 (gnus-demon-add-handler 'gnus-demon-scan-nocem 60 t))
202 (defun gnus-demon-scan-nocem ()
203 "Scan NoCeM groups for NoCeM messages."
204 (gnus-nocem-scan-groups))
206 (defun gnus-demon-add-disconnection ()
207 "Add daemonic server disconnection to Gnus."
208 (gnus-demon-add-handler 'gnus-demon-close-connections nil 30))
210 (defun gnus-demon-close-connections ()
211 (gnus-close-backends))
213 (defun gnus-demon-add-scanmail ()
214 "Add daemonic scanning of mail from the mail backends."
215 (gnus-demon-add-handler 'gnus-demon-scan-mail 120 60))
217 (defun gnus-demon-scan-mail ()
218 (let ((servers gnus-opened-servers)
220 (while (setq server (car (pop servers)))
221 (and (gnus-check-backend-function 'request-scan (car server))
222 (or (gnus-server-opened server)
223 (gnus-open-server server))
224 (gnus-request-scan nil server)))))
226 (defun gnus-demon-add-rescan ()
227 "Add daemonic scanning of new articles from all backends."
228 (gnus-demon-add-handler 'gnus-demon-scan-news 120 60))
230 (defun gnus-demon-scan-news ()
233 (set-buffer gnus-group-buffer)
234 (gnus-group-get-new-news))))
236 (provide 'gnus-demon)
238 ;;; gnus-demon.el ends here