1 /* timers.c --- detecting when the user is idle, and other timer-related tasks.
2 * xscreensaver, Copyright (c) 1991-1997, 1998
3 * Jamie Zawinski <jwz@jwz.org>
5 * Permission to use, copy, modify, distribute, and sell this software and its
6 * documentation for any purpose is hereby granted without fee, provided that
7 * the above copyright notice appear in all copies and that both that
8 * copyright notice and this permission notice appear in supporting
9 * documentation. No representations are made about the suitability of this
10 * software for any purpose. It is provided "as is" without express or
18 /* #define DEBUG_TIMERS */
22 #include <X11/Intrinsic.h>
26 # include <X11/Xmu/Error.h>
28 # include <Xmu/Error.h>
30 # else /* !HAVE_XMU */
32 #endif /* !HAVE_XMU */
34 #ifdef HAVE_XIDLE_EXTENSION
35 #include <X11/extensions/xidle.h>
36 #endif /* HAVE_XIDLE_EXTENSION */
38 #ifdef HAVE_MIT_SAVER_EXTENSION
39 #include <X11/extensions/scrnsaver.h>
40 #endif /* HAVE_MIT_SAVER_EXTENSION */
42 #ifdef HAVE_SGI_SAVER_EXTENSION
43 #include <X11/extensions/XScreenSaver.h>
44 #endif /* HAVE_SGI_SAVER_EXTENSION */
46 #ifdef HAVE_XHPDISABLERESET
47 # include <X11/XHPlib.h>
48 extern Bool hp_locked_p; /* from windows.c */
49 #endif /* HAVE_XHPDISABLERESET */
51 #include "xscreensaver.h"
53 #ifdef HAVE_PROC_INTERRUPTS
54 static Bool proc_interrupts_activity_p (saver_info *si);
55 #endif /* HAVE_PROC_INTERRUPTS */
59 idle_timer (XtPointer closure, XtIntervalId *id)
61 saver_info *si = (saver_info *) closure;
63 /* What an amazingly shitty design. Not only does Xt execute timeout
64 events from XtAppNextEvent() instead of from XtDispatchEvent(), but
65 there is no way to tell Xt to block until there is an X event OR a
66 timeout happens. Once your timeout proc is called, XtAppNextEvent()
67 still won't return until a "real" X event comes in.
69 So this function pushes a stupid, gratuitous, unnecessary event back
70 on the event queue to force XtAppNextEvent to return Right Fucking Now.
71 When the code in sleep_until_idle() sees an event of type XAnyEvent,
72 which the server never generates, it knows that a timeout has occurred.
75 fake_event.type = 0; /* XAnyEvent type, ignored. */
76 fake_event.xany.display = si->dpy;
77 fake_event.xany.window = 0;
78 XPutBackEvent (si->dpy, &fake_event);
83 schedule_wakeup_event (saver_info *si, Time when, Bool verbose_p)
85 /* Wake up periodically to ask the server if we are idle. */
86 si->timer_id = XtAppAddTimeOut (si->app, when, idle_timer,
91 fprintf (stderr, "%s: starting idle_timer (%ld, %ld)\n",
92 blurb(), when, si->timer_id);
93 #endif /* DEBUG_TIMERS */
98 notice_events (saver_info *si, Window window, Bool top_p)
100 saver_preferences *p = &si->prefs;
101 XWindowAttributes attrs;
102 unsigned long events;
103 Window root, parent, *kids;
106 if (XtWindowToWidget (si->dpy, window))
107 /* If it's one of ours, don't mess up its event mask. */
110 if (!XQueryTree (si->dpy, window, &root, &parent, &kids, &nkids))
115 XGetWindowAttributes (si->dpy, window, &attrs);
116 events = ((attrs.all_event_masks | attrs.do_not_propagate_mask)
119 /* Select for SubstructureNotify on all windows.
120 Select for KeyPress on all windows that already have it selected.
121 Do we need to select for ButtonRelease? I don't think so.
123 XSelectInput (si->dpy, window, SubstructureNotifyMask | events);
125 if (top_p && p->verbose_p && (events & KeyPressMask))
127 /* Only mention one window per tree (hack hack). */
128 fprintf (stderr, "%s: selected KeyPress on 0x%lX\n", blurb(),
129 (unsigned long) window);
136 notice_events (si, kids [--nkids], top_p);
137 XFree ((char *) kids);
143 BadWindow_ehandler (Display *dpy, XErrorEvent *error)
145 /* When we notice a window being created, we spawn a timer that waits
146 30 seconds or so, and then selects events on that window. This error
147 handler is used so that we can cope with the fact that the window
148 may have been destroyed <30 seconds after it was created.
150 if (error->error_code == BadWindow ||
151 error->error_code == BadMatch ||
152 error->error_code == BadDrawable)
155 return saver_ehandler (dpy, error);
159 struct notice_events_timer_arg {
165 notice_events_timer (XtPointer closure, XtIntervalId *id)
167 struct notice_events_timer_arg *arg =
168 (struct notice_events_timer_arg *) closure;
170 XErrorHandler old_handler = XSetErrorHandler (BadWindow_ehandler);
172 saver_info *si = arg->si;
173 Window window = arg->w;
176 notice_events (si, window, True);
177 XSync (si->dpy, False);
178 XSetErrorHandler (old_handler);
182 start_notice_events_timer (saver_info *si, Window w, Bool verbose_p)
184 saver_preferences *p = &si->prefs;
185 struct notice_events_timer_arg *arg =
186 (struct notice_events_timer_arg *) malloc(sizeof(*arg));
189 XtAppAddTimeOut (si->app, p->notice_events_timeout, notice_events_timer,
193 fprintf (stderr, "%s: starting notice_events_timer for 0x%X (%lu)\n",
194 blurb(), (unsigned int) w, p->notice_events_timeout);
198 /* When the screensaver is active, this timer will periodically change
202 cycle_timer (XtPointer closure, XtIntervalId *id)
204 saver_info *si = (saver_info *) closure;
205 saver_preferences *p = &si->prefs;
206 Time how_long = p->cycle;
210 fprintf (stderr, "%s: dialog box up; delaying hack change.\n",
212 how_long = 30000; /* 30 secs */
216 maybe_reload_init_file (si);
218 fprintf (stderr, "%s: changing graphics hacks.\n", blurb());
219 kill_screenhack (si);
220 spawn_screenhack (si, False);
222 si->cycle_id = XtAppAddTimeOut (si->app, how_long, cycle_timer,
227 fprintf (stderr, "%s: starting cycle_timer (%ld, %ld)\n",
228 blurb(), how_long, si->cycle_id);
229 #endif /* DEBUG_TIMERS */
234 activate_lock_timer (XtPointer closure, XtIntervalId *id)
236 saver_info *si = (saver_info *) closure;
237 saver_preferences *p = &si->prefs;
240 fprintf (stderr, "%s: timed out; activating lock\n", blurb());
243 #ifdef HAVE_XHPDISABLERESET
246 XHPDisableReset (si->dpy); /* turn off C-Sh-Reset */
253 /* Call this when user activity (or "simulated" activity) has been noticed.
256 reset_timers (saver_info *si)
258 saver_preferences *p = &si->prefs;
259 if (si->using_mit_saver_extension || si->using_sgi_saver_extension)
266 fprintf (stderr, "%s: killing idle_timer (%ld, %ld)\n",
267 blurb(), p->timeout, si->timer_id);
268 #endif /* DEBUG_TIMERS */
269 XtRemoveTimeOut (si->timer_id);
272 schedule_wakeup_event (si, p->timeout, p->verbose_p); /* sets si->timer_id */
274 if (si->cycle_id) abort (); /* no cycle timer when inactive */
276 si->last_activity_time = time ((time_t *) 0);
280 /* When we aren't using a server extension, this timer is used to periodically
281 wake up and poll the mouse position, which is possibly more reliable than
282 selecting motion events on every window.
285 check_pointer_timer (XtPointer closure, XtIntervalId *id)
288 saver_info *si = (saver_info *) closure;
289 saver_preferences *p = &si->prefs;
290 Bool active_p = False;
292 if (!si->using_proc_interrupts &&
293 (si->using_xidle_extension ||
294 si->using_mit_saver_extension ||
295 si->using_sgi_saver_extension))
296 /* If an extension is in use, we should not be polling the mouse.
297 Unless we're also checking /proc/interrupts, in which case, we should.
301 si->check_pointer_timer_id =
302 XtAppAddTimeOut (si->app, p->pointer_timeout, check_pointer_timer,
305 for (i = 0; i < si->nscreens; i++)
307 saver_screen_info *ssi = &si->screens[i];
309 int root_x, root_y, x, y;
312 XQueryPointer (si->dpy, ssi->screensaver_window, &root, &child,
313 &root_x, &root_y, &x, &y, &mask);
315 if (root_x == ssi->poll_mouse_last_root_x &&
316 root_y == ssi->poll_mouse_last_root_y &&
317 child == ssi->poll_mouse_last_child &&
318 mask == ssi->poll_mouse_last_mask)
325 if (root_x == ssi->poll_mouse_last_root_x &&
326 root_y == ssi->poll_mouse_last_root_y &&
327 child == ssi->poll_mouse_last_child)
328 fprintf (stderr, "%s: modifiers changed at %s on screen %d.\n",
329 blurb(), timestring(), i);
331 fprintf (stderr, "%s: pointer moved at %s on screen %d.\n",
332 blurb(), timestring(), i);
333 #endif /* DEBUG_TIMERS */
335 si->last_activity_screen = ssi;
336 ssi->poll_mouse_last_root_x = root_x;
337 ssi->poll_mouse_last_root_y = root_y;
338 ssi->poll_mouse_last_child = child;
339 ssi->poll_mouse_last_mask = mask;
342 #ifdef HAVE_PROC_INTERRUPTS
344 si->using_proc_interrupts &&
345 proc_interrupts_activity_p (si))
349 fprintf (stderr, "%s: /proc/interrupts activity at %s.\n",
350 blurb(), timestring());
351 # endif /* DEBUG_TIMERS */
354 #endif /* HAVE_PROC_INTERRUPTS */
362 dispatch_event (saver_info *si, XEvent *event)
364 /* If this is for the splash dialog, pass it along.
365 Note that the password dialog is handled with its own event loop,
366 so events for that window will never come through here.
368 if (si->splash_dialog && event->xany.window == si->splash_dialog)
369 handle_splash_event (si, event);
371 XtDispatchEvent (event);
375 /* methods of detecting idleness:
377 explicitly informed by SGI SCREEN_SAVER server event;
378 explicitly informed by MIT-SCREEN-SAVER server event;
379 poll server idle time with XIDLE extension;
380 select events on all windows, and note absence of recent events;
381 note that /proc/interrupts has not changed in a while;
382 activated by clientmessage.
384 methods of detecting non-idleness:
386 read events on the xscreensaver window;
387 explicitly informed by SGI SCREEN_SAVER server event;
388 explicitly informed by MIT-SCREEN-SAVER server event;
389 select events on all windows, and note events on any of them;
390 note that /proc/interrupts has changed;
391 deactivated by clientmessage.
393 I trust that explains why this function is a big hairy mess.
396 sleep_until_idle (saver_info *si, Bool until_idle_p)
398 saver_preferences *p = &si->prefs;
401 /* We need to select events on all windows if we're not using any extensions.
402 Otherwise, we don't need to. */
403 Bool scanning_all_windows = !(si->using_xidle_extension ||
404 si->using_mit_saver_extension ||
405 si->using_sgi_saver_extension);
407 /* We need to periodically wake up and check for idleness if we're not using
408 any extensions, or if we're using the XIDLE extension. The other two
409 extensions explicitly deliver events when we go idle/non-idle, so we
410 don't need to poll. */
411 Bool polling_for_idleness = !(si->using_mit_saver_extension ||
412 si->using_sgi_saver_extension);
414 /* Whether we need to periodically wake up and check to see if the mouse has
415 moved. We only need to do this when not using any extensions. The reason
416 this isn't the same as `polling_for_idleness' is that the "idleness" poll
417 can happen (for example) 5 minutes from now, whereas the mouse-position
418 poll should happen with low periodicity. We don't need to poll the mouse
419 position with the XIDLE extension, but we do need to periodically wake up
420 and query the server with that extension. For our purposes, polling
421 /proc/interrupts is just like polling the mouse position. It has to
422 happen on the same kind of schedule. */
423 Bool polling_mouse_position = (si->using_proc_interrupts ||
424 !(si->using_xidle_extension ||
425 si->using_mit_saver_extension ||
426 si->using_sgi_saver_extension));
430 if (polling_for_idleness)
431 /* This causes a no-op event to be delivered to us in a while, so that
432 we come back around through the event loop again. Use of this timer
433 is economical: for example, if the screensaver should come on in 5
434 minutes, and the user has been idle for 2 minutes, then this
435 timeout will go off no sooner than 3 minutes from now. */
436 schedule_wakeup_event (si, p->timeout, p->verbose_p);
438 if (polling_mouse_position)
439 /* Check to see if the mouse has moved, and set up a repeating timer
440 to do so periodically (typically, every 5 seconds.) */
441 check_pointer_timer ((XtPointer) si, 0);
446 XtAppNextEvent (si->app, &event);
448 switch (event.xany.type) {
449 case 0: /* our synthetic "timeout" event has been signalled */
453 #ifdef HAVE_XIDLE_EXTENSION
454 if (si->using_xidle_extension)
456 /* The XIDLE extension uses the synthetic event to prod us into
457 re-asking the server how long the user has been idle. */
458 if (! XGetIdleTime (si->dpy, &idle))
460 fprintf (stderr, "%s: XGetIdleTime() failed.\n", blurb());
461 saver_exit (si, 1, 0);
465 #endif /* HAVE_XIDLE_EXTENSION */
466 #ifdef HAVE_MIT_SAVER_EXTENSION
467 if (si->using_mit_saver_extension)
469 /* We don't need to do anything in this case - the synthetic
470 event isn't necessary, as we get sent specific events
471 to wake us up. In fact, this event generally shouldn't
472 be being delivered when the MIT extension is in use. */
476 #endif /* HAVE_MIT_SAVER_EXTENSION */
477 #ifdef HAVE_SGI_SAVER_EXTENSION
478 if (si->using_sgi_saver_extension)
480 /* We don't need to do anything in this case - the synthetic
481 event isn't necessary, as we get sent specific events
482 to wake us up. In fact, this event generally shouldn't
483 be being delivered when the SGI extension is in use. */
487 #endif /* HAVE_SGI_SAVER_EXTENSION */
489 /* Otherwise, no server extension is in use. The synthetic
490 event was to tell us to wake up and see if the user is now
491 idle. Compute the amount of idle time by comparing the
492 `last_activity_time' to the wall clock. The l_a_t was set
493 by calling `reset_timers()', which is called only in only
494 two situations: when polling the mouse position has revealed
495 the the mouse has moved (user activity) or when we have read
496 an event (again, user activity.)
498 idle = 1000 * (si->last_activity_time - time ((time_t *) 0));
501 if (idle >= p->timeout)
503 /* Look, we've been idle long enough. We're done. */
508 /* The event went off, but it turns out that the user has not
509 yet been idle for long enough. So re-signal the event.
511 if (polling_for_idleness)
512 schedule_wakeup_event (si, p->timeout - idle, p->verbose_p);
518 if (handle_clientmessage (si, &event, until_idle_p))
523 /* A window has been created on the screen somewhere. If we're
524 supposed to scan all windows for events, prepare this window. */
525 if (scanning_all_windows)
527 Window w = event.xcreatewindow.window;
529 start_notice_events_timer (si, w, p->verbose_p);
530 #else /* !DEBUG_TIMERS */
531 start_notice_events_timer (si, w, False);
532 #endif /* !DEBUG_TIMERS */
545 if (event.xany.type == MotionNotify)
546 fprintf (stderr,"%s: MotionNotify at %s\n",blurb(),timestring());
547 else if (event.xany.type == KeyPress)
548 fprintf (stderr, "%s: KeyPress seen on 0x%X at %s\n", blurb(),
549 (unsigned int) event.xkey.window, timestring ());
550 else if (event.xany.type == ButtonPress)
551 fprintf (stderr, "%s: ButtonPress seen on 0x%X at %s\n", blurb(),
552 (unsigned int) event.xbutton.window, timestring ());
554 #endif /* DEBUG_TIMERS */
556 /* If any widgets want to handle this event, let them. */
557 dispatch_event (si, &event);
559 /* We got a user event.
560 If we're waiting for the user to become active, this is it.
561 If we're waiting until the user becomes idle, reset the timers
562 (since now we have longer to wait.)
567 (event.xany.type == MotionNotify ||
568 event.xany.type == KeyRelease))
569 /* When we're demoing a single hack, mouse motion doesn't
570 cause deactivation. Only clicks and keypresses do. */
573 /* If we're not demoing, then any activity causes deactivation.
584 #ifdef HAVE_MIT_SAVER_EXTENSION
585 if (event.type == si->mit_saver_ext_event_number)
587 /* This event's number is that of the MIT-SCREEN-SAVER server
588 extension. This extension has one event number, and the event
589 itself contains sub-codes that say what kind of event it was
590 (an "idle" or "not-idle" event.)
592 XScreenSaverNotifyEvent *sevent =
593 (XScreenSaverNotifyEvent *) &event;
594 if (sevent->state == ScreenSaverOn)
598 fprintf (stderr, "%s: MIT ScreenSaverOn event received.\n",
601 /* Get the "real" server window(s) out of the way as soon
603 for (i = 0; i < si->nscreens; i++)
605 saver_screen_info *ssi = &si->screens[i];
606 if (ssi->server_mit_saver_window &&
607 window_exists_p (si->dpy,
608 ssi->server_mit_saver_window))
609 XUnmapWindow (si->dpy, ssi->server_mit_saver_window);
612 if (sevent->kind != ScreenSaverExternal)
615 "%s: ScreenSaverOn event wasn't of type External!\n",
622 else if (sevent->state == ScreenSaverOff)
625 fprintf (stderr, "%s: MIT ScreenSaverOff event received.\n",
632 "%s: unknown MIT-SCREEN-SAVER event %d received!\n",
633 blurb(), sevent->state);
637 #endif /* HAVE_MIT_SAVER_EXTENSION */
640 #ifdef HAVE_SGI_SAVER_EXTENSION
641 if (event.type == (si->sgi_saver_ext_event_number + ScreenSaverStart))
643 /* The SGI SCREEN_SAVER server extension has two event numbers,
644 and this event matches the "idle" event. */
646 fprintf (stderr, "%s: SGI ScreenSaverStart event received.\n",
652 else if (event.type == (si->sgi_saver_ext_event_number +
655 /* The SGI SCREEN_SAVER server extension has two event numbers,
656 and this event matches the "idle" event. */
658 fprintf (stderr, "%s: SGI ScreenSaverEnd event received.\n",
664 #endif /* HAVE_SGI_SAVER_EXTENSION */
666 /* Just some random event. Let the Widgets handle it, if desired. */
667 dispatch_event (si, &event);
673 /* If there's a user event on the queue, swallow it.
674 If we're using a server extension, and the user becomes active, we
675 get the extension event before the user event -- so the keypress or
676 motion or whatever is still on the queue. This makes "unfade" not
677 work, because it sees that event, and bugs out. (This problem
678 doesn't exhibit itself without an extension, because in that case,
679 there's only one event generated by user activity, not two.)
681 XCheckMaskEvent (si->dpy, (KeyPressMask|ButtonPressMask|PointerMotionMask),
685 if (si->check_pointer_timer_id)
687 XtRemoveTimeOut (si->check_pointer_timer_id);
688 si->check_pointer_timer_id = 0;
692 XtRemoveTimeOut (si->timer_id);
696 if (until_idle_p && si->cycle_id) /* no cycle timer when inactive */
704 /* Some crap for dealing with /proc/interrupts.
706 On Linux systems, it's possible to see the hardware interrupt count
707 associated with the keyboard. We can therefore use that as another method
708 of detecting idleness.
710 Why is it a good idea to do this? Because it lets us detect keyboard
711 activity that is not associated with X events. For example, if the user
712 has switched to another virtual console, it's good for xscreensaver to not
713 be running graphics hacks on the (non-visible) X display. The common
714 complaint that checking /proc/interrupts addresses is that the user is
715 playing Quake on a non-X console, and the GL hacks are perceptibly slowing
718 This is tricky for a number of reasons.
720 * First, we must be sure to only do this when running on an X server that
721 is on the local machine (because otherwise, we'd be reacting to the
722 wrong keyboard.) The way we do this is by noting that the $DISPLAY is
723 pointing to display 0 on the local machine. It *could* be that display
724 1 is also on the local machine (e.g., two X servers, each on a different
725 virtual-terminal) but it's also possible that screen 1 is an X terminal,
726 using this machine as the host. So we can't take that chance.
728 * Second, one can only access these interrupt numbers in a completely
729 and utterly brain-damaged way. You would think that one would use an
730 ioctl for this. But no. The ONLY way to get this information is to
731 open the pseudo-file /proc/interrupts AS A FILE, and read the numbers
732 out of it TEXTUALLY. Because this is Unix, and all the world's a file,
733 and the only real data type is the short-line sequence of ASCII bytes.
735 Now it's all well and good that the /proc/interrupts pseudo-file
736 exists; that's a clever idea, and a useful API for things that are
737 already textually oriented, like shell scripts, and users doing
738 interactive debugging sessions. But to make a *C PROGRAM* open a file
739 and parse the textual representation of integers out of it is just
742 * Third, you can't just hold the file open, and fseek() back to the
743 beginning to get updated data! If you do that, the data never changes.
744 And I don't want to call open() every five seconds, because I don't want
745 to risk going to disk for any inodes. It turns out that if you dup()
746 it early, then each copy gets fresh data, so we can get around that in
747 this way (but for how many releases, one might wonder?)
749 * Fourth, the format of the output of the /proc/interrupts file is
750 undocumented, and has changed several times already! In Linux 2.0.33,
751 even on a multiprocessor machine, it looks like this:
756 but on later kernels with MP machines, it looks like this:
759 0: 1671450 1672618 IO-APIC-edge timer
760 1: 13037 13495 IO-APIC-edge keyboard
762 Joy! So how are we expected to parse that? Well, this code doesn't
763 parse it: it saves the last line with the string "keyboard" in it, and
764 does a string-comparison to note when it has changed.
766 Thanks to Nat Friedman <nat@nat.org> for figuring out all of this crap.
768 Note that this only checks for lines with "keyboard" in them. Perhaps we
769 should also be checking for lines with "PS/2 Mouse" in them. But that
770 would obviously fail to work for regular serial mice, and obviously just
771 using COM1 would be bad news (turn off the screensaver because the modem
776 #ifdef HAVE_PROC_INTERRUPTS
778 #define PROC_INTERRUPTS "/proc/interrupts"
781 query_proc_interrupts_available (saver_info *si, const char **why)
783 /* We can use /proc/interrupts if $DISPLAY points to :0, and if the
784 "/proc/interrupts" file exists and is readable.
789 if (!display_is_on_console_p (si))
791 if (why) *why = "not on primary console";
795 f = fopen (PROC_INTERRUPTS, "r");
805 proc_interrupts_activity_p (saver_info *si)
810 static char last_line[255] = { 0, };
811 char new_line[sizeof(last_line)];
815 /* First time -- open the file. */
816 f0 = fopen (PROC_INTERRUPTS, "r");
820 sprintf(buf, "%s: error opening %s", blurb(), PROC_INTERRUPTS);
826 if (f0 == (FILE *) -1) /* means we got an error initializing. */
829 fd = dup (fileno (f0));
833 sprintf(buf, "%s: could not dup() the %s fd", blurb(), PROC_INTERRUPTS);
838 f1 = fdopen (fd, "r");
842 sprintf(buf, "%s: could not fdopen() the %s fd", blurb(),
848 /* Actually, I'm unclear on why this fseek() is necessary, given the timing
849 of the dup() above, but it is. */
850 if (fseek (f1, 0, SEEK_SET) != 0)
853 sprintf(buf, "%s: error rewinding %s", blurb(), PROC_INTERRUPTS);
858 /* Now read through the pseudo-file until we find the "keyboard" line. */
860 while (fgets (new_line, sizeof(new_line)-1, f1))
861 if (strstr (new_line, "keyboard"))
863 Bool diff = (*last_line &&
864 !!strcmp (new_line, last_line));
865 strcpy (last_line, new_line); /* save this line for next time */
870 /* If we got here, we didn't find a "keyboard" line in the file at all. */
871 fprintf (stderr, "%s: no keyboard data in %s?\n", blurb(), PROC_INTERRUPTS);
877 if (f0 && f0 != (FILE *) -1)
884 #endif /* HAVE_PROC_INTERRUPTS */
887 /* This timer goes off every few minutes, whether the user is idle or not,
888 to try and clean up anything that has gone wrong.
890 It calls disable_builtin_screensaver() so that if xset has been used,
891 or some other program (like xlock) has messed with the XSetScreenSaver()
892 settings, they will be set back to sensible values (if a server extension
893 is in use, messing with xlock can cause xscreensaver to never get a wakeup
894 event, and could cause monitor power-saving to occur, and all manner of
897 If the screen is currently blanked, it raises the window, in case some
898 other window has been mapped on top of it.
900 If the screen is currently blanked, and there is no hack running, it
901 clears the window, in case there is an error message printed on it (we
902 don't want the error message to burn in.)
906 watchdog_timer (XtPointer closure, XtIntervalId *id)
908 saver_info *si = (saver_info *) closure;
910 disable_builtin_screensaver (si, False);
912 if (si->screen_blanked_p)
914 Bool running_p = screenhack_running_p(si);
917 if (si->prefs.verbose_p)
918 fprintf (stderr, "%s: watchdog timer raising %sscreen.\n",
919 blurb(), (running_p ? "" : "and clearing "));
920 #endif /* DEBUG_TIMERS */
922 raise_window (si, True, True, running_p);
924 if (!monitor_powered_on_p (si))
926 if (si->prefs.verbose_p)
928 "%s: server reports that monitor has powered down; "
929 "killing running hacks.\n", blurb());
930 kill_screenhack (si);
937 reset_watchdog_timer (saver_info *si, Bool on_p)
939 saver_preferences *p = &si->prefs;
943 XtRemoveTimeOut (si->watchdog_id);
947 if (on_p && p->watchdog_timeout)
949 si->watchdog_id = XtAppAddTimeOut (si->app, p->watchdog_timeout,
950 watchdog_timer, (XtPointer) si);
954 fprintf (stderr, "%s: restarting watchdog_timer (%ld, %ld)\n",
955 blurb(), p->watchdog_timeout, si->watchdog_id);
956 #endif /* DEBUG_TIMERS */