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
21 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
29 (eval-when-compile (require 'cl))
31 (defvar gnus-demon-handlers nil
32 "Alist of daemonic handlers to be run at intervals.
33 Each handler is a list on the form
37 FUNCTION is the function to be called.
38 TIME is the number of `gnus-demon-timestep's between each call.
39 If nil, never call. If t, call each `gnus-demon-timestep'.
40 If IDLE is t, only call if Emacs has been idle for a while. If IDLE
41 is a number, only call when Emacs has been idle more than this number
42 of `gnus-demon-timestep's. If IDLE is nil, don't care about
43 idleness. If IDLE is a number and TIME is nil, then call once each
44 time Emacs has been idle for IDLE `gnus-demon-timestep's.")
46 (defvar gnus-demon-timestep 60
47 "*Number of seconds in each demon timestep.")
49 ;;; Internal variables.
51 (defvar gnus-demon-timer nil)
52 (defvar gnus-demon-idle-has-been-called nil)
53 (defvar gnus-demon-idle-time 0)
54 (defvar gnus-demon-handler-state nil)
55 (defvar gnus-demon-is-idle nil)
56 (defvar gnus-demon-last-keys nil)
59 (autoload 'cancel-timer "timer")
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 (defun gnus-demon-cancel ()
102 "Cancel any Gnus daemons."
104 (and gnus-demon-timer
105 (cancel-timer gnus-demon-timer))
106 (setq gnus-demon-timer nil
109 (defun gnus-demon-is-idle-p ()
110 "Whether Emacs is idle or not."
111 ;; We do this simply by comparing the 100 most recent keystrokes
112 ;; with the ones we had last time. If they are the same, one might
113 ;; guess that Emacs is indeed idle. This only makes sense if one
114 ;; calls this function seldom -- like once a minute, which is what
116 (let ((keys (recent-keys)))
117 (or (equal keys gnus-demon-last-keys)
119 (setq gnus-demon-last-keys keys)
122 (defun gnus-demon-time-to-step (time)
123 "Find out how many seconds to TIME, which is on the form \"17:43\"."
124 (if (not (stringp time))
126 (let* ((date (current-time-string))
127 (dv (timezone-parse-date date))
128 (tdate (timezone-make-arpa-date
129 (string-to-number (aref dv 0))
130 (string-to-number (aref dv 1))
131 (string-to-number (aref dv 2)) time
132 (or (aref dv 4) "UT")))
133 (nseconds (gnus-time-minus
134 (gnus-encode-date tdate) (gnus-encode-date date))))
136 (/ (if (< nseconds 0)
137 (+ nseconds (* 60 60 24))
138 nseconds) gnus-demon-timestep)))))
141 "The Gnus daemon that takes care of running all Gnus handlers."
142 ;; Increase or reset the time Emacs has been idle.
143 (if (gnus-demon-is-idle-p)
144 (incf gnus-demon-idle-time)
145 (setq gnus-demon-idle-time 0)
146 (setq gnus-demon-idle-has-been-called nil))
147 ;; Then we go through all the handler and call those that are
148 ;; sufficiently ripe.
149 (let ((handlers gnus-demon-handler-state)
152 (setq handler (pop handlers))
154 ((numberp (setq time (nth 1 handler)))
155 ;; These handlers use a regular timeout mechanism. We decrease
156 ;; the timer if it hasn't reached zero yet.
158 (setcar (nthcdr 1 handler) (decf time)))
159 (and (zerop time) ; If the timer now is zero...
160 (or (not (setq idle (nth 2 handler))) ; Don't care about idle.
161 (and (numberp idle) ; Numerical idle...
162 (< idle gnus-demon-idle-time)) ; Idle timed out.
163 gnus-demon-is-idle) ; Or just need to be idle.
164 ;; So we call the handler.
166 (funcall (car handler))
167 ;; And reset the timer.
168 (setcar (nthcdr 1 handler)
169 (gnus-demon-time-to-step
170 (nth 1 (assq (car handler) gnus-demon-handlers)))))))
171 ;; These are only supposed to be called when Emacs is idle.
172 ((null (setq idle (nth 2 handler)))
175 ((not (numberp idle))
176 ;; We want to call this handler each and every time that
178 (funcall (car handler)))
180 ;; We want to call this handler only if Emacs has been idle
181 ;; for a specified number of timesteps.
182 (and (not (memq (car handler) gnus-demon-idle-has-been-called))
183 (< idle gnus-demon-idle-time)
185 (funcall (car handler))
186 ;; Make sure the handler won't be called once more in
188 (push (car handler) gnus-demon-idle-has-been-called))))))))
190 (defun gnus-demon-add-nocem ()
191 "Add daemonic NoCeM handling to Gnus."
192 (gnus-demon-add-handler 'gnus-demon-scan-nocem 60 t))
194 (defun gnus-demon-scan-nocem ()
195 (gnus-nocem-scan-groups))
197 (defun gnus-demon-add-disconnection ()
198 "Add daemonic server disconnection to Gnus."
199 (gnus-demon-add-handler 'gnus-demon-close-connections nil 30))
201 (defun gnus-demon-close-connections ()
202 (gnus-close-backends))
204 (defun gnus-demon-add-scanmail ()
205 "Add daemonic scanning of mail from the mail backends."
206 (gnus-demon-add-handler 'gnus-demon-scan-mail 120 60))
208 (defun gnus-demon-scan-mail ()
209 (let ((servers gnus-opened-servers)
212 (setq server (car (pop servers)))
213 (and (gnus-check-backend-function 'request-scan (car server))
214 (gnus-request-scan nil server)))))
216 (provide 'gnus-demon)
218 ;;; gnus-demon.el ends here