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.
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 'timezone-parse-date "timezone")
61 (autoload 'timezone-make-arpa-date "timezone"))
65 (defun gnus-demon-add-handler (function time idle)
66 "Add the handler FUNCTION to be run at TIME and IDLE."
67 ;; First remove any old handlers that use this function.
68 (gnus-demon-remove-handler function)
69 ;; Then add the new one.
70 (push (list function time idle) gnus-demon-handlers)
73 (defun gnus-demon-remove-handler (function &optional no-init)
74 "Remove the handler FUNCTION from the list of handlers."
75 (setq gnus-demon-handlers
76 (delq (assq function gnus-demon-handlers)
78 (or no-init (gnus-demon-init)))
80 (defun gnus-demon-init ()
81 "Initialize the Gnus daemon."
84 (if (null gnus-demon-handlers)
87 (setq gnus-demon-timer
89 gnus-demon-timestep gnus-demon-timestep 'gnus-demon))
90 ;; Reset control variables.
91 (setq gnus-demon-handler-state
94 (list (car handler) (gnus-demon-time-to-step (nth 1 handler))
97 (setq gnus-demon-idle-time 0)
98 (setq gnus-demon-idle-has-been-called nil)
99 (setq gnus-use-demon t)))
101 (gnus-add-shutdown 'gnus-demon-cancel 'gnus)
103 (defun gnus-demon-cancel ()
104 "Cancel any Gnus daemons."
106 (and gnus-demon-timer
107 (nnheader-cancel-timer gnus-demon-timer))
108 (setq gnus-demon-timer nil
110 (nnheader-cancel-function-timers 'gnus-demon))
112 (defun gnus-demon-is-idle-p ()
113 "Whether Emacs is idle or not."
114 ;; We do this simply by comparing the 100 most recent keystrokes
115 ;; with the ones we had last time. If they are the same, one might
116 ;; guess that Emacs is indeed idle. This only makes sense if one
117 ;; calls this function seldom -- like once a minute, which is what
119 (let ((keys (recent-keys)))
120 (or (equal keys gnus-demon-last-keys)
122 (setq gnus-demon-last-keys keys)
125 (defun gnus-demon-time-to-step (time)
126 "Find out how many seconds to TIME, which is on the form \"17:43\"."
127 (if (not (stringp time))
129 (let* ((date (current-time-string))
130 (dv (timezone-parse-date date))
131 (tdate (timezone-make-arpa-date
132 (string-to-number (aref dv 0))
133 (string-to-number (aref dv 1))
134 (string-to-number (aref dv 2)) time
135 (or (aref dv 4) "UT")))
136 (nseconds (gnus-time-minus
137 (gnus-encode-date tdate) (gnus-encode-date date))))
139 (/ (if (< nseconds 0)
140 (+ nseconds (* 60 60 24))
141 nseconds) gnus-demon-timestep)))))
144 "The Gnus daemon that takes care of running all Gnus handlers."
145 ;; Increase or reset the time Emacs has been idle.
146 (if (gnus-demon-is-idle-p)
147 (incf gnus-demon-idle-time)
148 (setq gnus-demon-idle-time 0)
149 (setq gnus-demon-idle-has-been-called nil))
150 ;; Then we go through all the handler and call those that are
151 ;; sufficiently ripe.
152 (let ((handlers gnus-demon-handler-state)
155 (setq handler (pop handlers))
157 ((numberp (setq time (nth 1 handler)))
158 ;; These handlers use a regular timeout mechanism. We decrease
159 ;; the timer if it hasn't reached zero yet.
161 (setcar (nthcdr 1 handler) (decf time)))
162 (and (zerop time) ; If the timer now is zero...
163 (or (not (setq idle (nth 2 handler))) ; Don't care about idle.
164 (and (numberp idle) ; Numerical idle...
165 (< idle gnus-demon-idle-time)) ; Idle timed out.
166 gnus-demon-is-idle) ; Or just need to be idle.
167 ;; So we call the handler.
169 (funcall (car handler))
170 ;; And reset the timer.
171 (setcar (nthcdr 1 handler)
172 (gnus-demon-time-to-step
173 (nth 1 (assq (car handler) gnus-demon-handlers)))))))
174 ;; These are only supposed to be called when Emacs is idle.
175 ((null (setq idle (nth 2 handler)))
178 ((not (numberp idle))
179 ;; We want to call this handler each and every time that
181 (funcall (car handler)))
183 ;; We want to call this handler only if Emacs has been idle
184 ;; for a specified number of timesteps.
185 (and (not (memq (car handler) gnus-demon-idle-has-been-called))
186 (< idle gnus-demon-idle-time)
188 (funcall (car handler))
189 ;; Make sure the handler won't be called once more in
191 (push (car handler) gnus-demon-idle-has-been-called))))))))
193 (defun gnus-demon-add-nocem ()
194 "Add daemonic NoCeM handling to Gnus."
195 (gnus-demon-add-handler 'gnus-demon-scan-nocem 60 t))
197 (defun gnus-demon-scan-nocem ()
198 "Scan NoCeM groups for NoCeM messages."
199 (gnus-nocem-scan-groups))
201 (defun gnus-demon-add-disconnection ()
202 "Add daemonic server disconnection to Gnus."
203 (gnus-demon-add-handler 'gnus-demon-close-connections nil 30))
205 (defun gnus-demon-close-connections ()
206 (gnus-close-backends))
208 (defun gnus-demon-add-scanmail ()
209 "Add daemonic scanning of mail from the mail backends."
210 (gnus-demon-add-handler 'gnus-demon-scan-mail 120 60))
212 (defun gnus-demon-scan-mail ()
213 (let ((servers gnus-opened-servers)
215 (while (setq server (car (pop servers)))
216 (and (gnus-check-backend-function 'request-scan (car server))
217 (or (gnus-server-opened server)
218 (gnus-open-server server))
219 (gnus-request-scan nil server)))))
221 (provide 'gnus-demon)
223 ;;; gnus-demon.el ends here