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.
30 (eval-when-compile (require 'cl))
32 (defvar gnus-demon-handlers nil
33 "Alist of daemonic handlers to be run at intervals.
34 Each handler is a list on the form
38 FUNCTION is the function to be called.
39 TIME is the number of `gnus-demon-timestep's between each call.
40 If nil, never call. If t, call each `gnus-demon-timestep'.
41 If IDLE is t, only call if Emacs has been idle for a while. If IDLE
42 is a number, only call when Emacs has been idle more than this number
43 of `gnus-demon-timestep's. If IDLE is nil, don't care about
44 idleness. If IDLE is a number and TIME is nil, then call once each
45 time Emacs has been idle for IDLE `gnus-demon-timestep's.")
47 (defvar gnus-demon-timestep 60
48 "*Number of seconds in each demon timestep.")
50 ;;; Internal variables.
52 (defvar gnus-demon-timer nil)
53 (defvar gnus-demon-idle-has-been-called nil)
54 (defvar gnus-demon-idle-time 0)
55 (defvar gnus-demon-handler-state nil)
56 (defvar gnus-demon-is-idle nil)
57 (defvar gnus-demon-last-keys nil)
60 (autoload 'cancel-timer "timer")
61 (autoload 'timezone-parse-date "timezone")
62 (autoload 'timezone-make-arpa-date "timezone"))
66 (defun gnus-demon-add-handler (function time idle)
67 "Add the handler FUNCTION to be run at TIME and IDLE."
68 ;; First remove any old handlers that use this function.
69 (gnus-demon-remove-handler function)
70 ;; Then add the new one.
71 (push (list function time idle) gnus-demon-handlers)
74 (defun gnus-demon-remove-handler (function &optional no-init)
75 "Remove the handler FUNCTION from the list of handlers."
76 (setq gnus-demon-handlers
77 (delq (assq function gnus-demon-handlers)
79 (or no-init (gnus-demon-init)))
81 (defun gnus-demon-init ()
82 "Initialize the Gnus daemon."
85 (if (null gnus-demon-handlers)
88 (setq gnus-demon-timer
90 gnus-demon-timestep gnus-demon-timestep 'gnus-demon))
91 ;; Reset control variables.
92 (setq gnus-demon-handler-state
95 (list (car handler) (gnus-demon-time-to-step (nth 1 handler))
98 (setq gnus-demon-idle-time 0)
99 (setq gnus-demon-idle-has-been-called nil)
100 (setq gnus-use-demon t)))
102 (defun gnus-demon-cancel ()
103 "Cancel any Gnus daemons."
105 (and gnus-demon-timer
106 (cancel-timer gnus-demon-timer))
107 (setq gnus-demon-timer nil
110 (defun gnus-demon-is-idle-p ()
111 "Whether Emacs is idle or not."
112 ;; We do this simply by comparing the 100 most recent keystrokes
113 ;; with the ones we had last time. If they are the same, one might
114 ;; guess that Emacs is indeed idle. This only makes sense if one
115 ;; calls this function seldom -- like once a minute, which is what
117 (let ((keys (recent-keys)))
118 (or (equal keys gnus-demon-last-keys)
120 (setq gnus-demon-last-keys keys)
123 (defun gnus-demon-time-to-step (time)
124 "Find out how many seconds to TIME, which is on the form \"17:43\"."
125 (if (not (stringp time))
127 (let* ((date (current-time-string))
128 (dv (timezone-parse-date date))
129 (tdate (timezone-make-arpa-date
130 (string-to-number (aref dv 0))
131 (string-to-number (aref dv 1))
132 (string-to-number (aref dv 2)) time
133 (or (aref dv 4) "UT")))
134 (nseconds (gnus-time-minus
135 (gnus-encode-date tdate) (gnus-encode-date date))))
137 (/ (if (< nseconds 0)
138 (+ nseconds (* 60 60 24))
139 nseconds) gnus-demon-timestep)))))
142 "The Gnus daemon that takes care of running all Gnus handlers."
143 ;; Increase or reset the time Emacs has been idle.
144 (if (gnus-demon-is-idle-p)
145 (incf gnus-demon-idle-time)
146 (setq gnus-demon-idle-time 0)
147 (setq gnus-demon-idle-has-been-called nil))
148 ;; Then we go through all the handler and call those that are
149 ;; sufficiently ripe.
150 (let ((handlers gnus-demon-handler-state)
153 (setq handler (pop handlers))
155 ((numberp (setq time (nth 1 handler)))
156 ;; These handlers use a regular timeout mechanism. We decrease
157 ;; the timer if it hasn't reached zero yet.
159 (setcar (nthcdr 1 handler) (decf time)))
160 (and (zerop time) ; If the timer now is zero...
161 (or (not (setq idle (nth 2 handler))) ; Don't care about idle.
162 (and (numberp idle) ; Numerical idle...
163 (< idle gnus-demon-idle-time)) ; Idle timed out.
164 gnus-demon-is-idle) ; Or just need to be idle.
165 ;; So we call the handler.
167 (funcall (car handler))
168 ;; And reset the timer.
169 (setcar (nthcdr 1 handler)
170 (gnus-demon-time-to-step
171 (nth 1 (assq (car handler) gnus-demon-handlers)))))))
172 ;; These are only supposed to be called when Emacs is idle.
173 ((null (setq idle (nth 2 handler)))
176 ((not (numberp idle))
177 ;; We want to call this handler each and every time that
179 (funcall (car handler)))
181 ;; We want to call this handler only if Emacs has been idle
182 ;; for a specified number of timesteps.
183 (and (not (memq (car handler) gnus-demon-idle-has-been-called))
184 (< idle gnus-demon-idle-time)
186 (funcall (car handler))
187 ;; Make sure the handler won't be called once more in
189 (push (car handler) gnus-demon-idle-has-been-called))))))))
191 (defun gnus-demon-add-nocem ()
192 "Add daemonic NoCeM handling to Gnus."
193 (gnus-demon-add-handler 'gnus-demon-scan-nocem 60 t))
195 (defun gnus-demon-scan-nocem ()
196 "Scan NoCeM groups for NoCeM messages."
197 (gnus-nocem-scan-groups))
199 (defun gnus-demon-add-disconnection ()
200 "Add daemonic server disconnection to Gnus."
201 (gnus-demon-add-handler 'gnus-demon-close-connections nil 30))
203 (defun gnus-demon-close-connections ()
204 (gnus-close-backends))
206 (defun gnus-demon-add-scanmail ()
207 "Add daemonic scanning of mail from the mail backends."
208 (gnus-demon-add-handler 'gnus-demon-scan-mail 120 60))
210 (defun gnus-demon-scan-mail ()
211 (let ((servers gnus-opened-servers)
214 (setq server (car (pop servers)))
215 (and (gnus-check-backend-function 'request-scan (car server))
216 (gnus-request-scan nil server)))))
218 (provide 'gnus-demon)
220 ;;; gnus-demon.el ends here