1 /* dpms.c --- syncing the X Display Power Management values
2 * xscreensaver, Copyright (c) 2001-2011 Jamie Zawinski <jwz@jwz.org>
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that
7 * copyright notice and this permission notice appear in supporting
8 * documentation. No representations are made about the suitability of this
9 * software for any purpose. It is provided "as is" without express or
13 /* Display Power Management System (DPMS.)
15 On XFree86 systems, "man xset" reports:
17 -dpms The -dpms option disables DPMS (Energy Star) features.
18 +dpms The +dpms option enables DPMS (Energy Star) features.
21 The dpms option allows the DPMS (Energy Star)
22 parameters to be set. The option can take up to three
23 numerical values, or the `force' flag followed by a
24 DPMS state. The `force' flags forces the server to
25 immediately switch to the DPMS state specified. The
26 DPMS state can be one of `standby', `suspend', or
27 `off'. When numerical values are given, they set the
28 inactivity period before the three modes are activated.
29 The first value given is for the `standby' mode, the
30 second is for the `suspend' mode, and the third is for
31 the `off' mode. Setting these values implicitly
32 enables the DPMS features. A value of zero disables a
35 However, note that the implementation is more than a little bogus,
36 in that there is code in /usr/X11R6/lib/libXdpms.a to implement all
37 the usual server-extension-querying utilities -- but there are no
38 prototypes in any header file! Thus, the prototypes here. (The
39 stuff in X11/extensions/dpms.h and X11/extensions/dpmsstr.h define
40 the raw X protcol, they don't define the API to libXdpms.a.)
43 Library: ftp://ftp.x.org/pub/R6.4/xc/doc/specs/Xext/DPMSLib.ms
44 Protocol: ftp://ftp.x.org/pub/R6.4/xc/doc/specs/Xext/DPMS.ms
54 #ifdef HAVE_DPMS_EXTENSION /* almost the whole file */
56 # include <X11/Xproto.h>
57 # include <X11/extensions/dpms.h>
58 /*# include <X11/extensions/dpmsstr.h>*/
60 /* Why this crap is not in a header file somewhere, I have no idea. Losers!
62 extern Bool DPMSQueryExtension (Display *, int *event_ret, int *err_ret);
63 extern Status DPMSGetVersion (Display *, int *major_ret, int *minor_ret);
64 extern Bool DPMSCapable (Display *);
65 extern Status DPMSInfo (Display *, CARD16 *power_level, BOOL *state);
66 extern Status DPMSEnable (Display *dpy);
67 extern Status DPMSDisable (Display *dpy);
68 extern Status DPMSForceLevel (Display *, CARD16 level);
69 extern Status DPMSSetTimeouts (Display *, CARD16 standby, CARD16 suspend,
71 extern Bool DPMSGetTimeouts (Display *, CARD16 *standby,
72 CARD16 *suspend, CARD16 *off);
74 #endif /* HAVE_DPMS_EXTENSION */
77 /* This file doesn't need the Xt headers, so stub these types out... */
79 #define XtAppContext void*
80 #define XrmDatabase void*
81 #define XtIntervalId void*
82 #define XtPointer void*
85 #include "xscreensaver.h"
87 #ifdef HAVE_DPMS_EXTENSION
89 static Bool error_handler_hit_p = False;
92 ignore_all_errors_ehandler (Display *dpy, XErrorEvent *error)
94 error_handler_hit_p = True;
100 sync_server_dpms_settings (Display *dpy, Bool enabled_p, Bool dpms_quickoff_p,
101 int standby_secs, int suspend_secs, int off_secs,
104 int event = 0, error = 0;
105 BOOL o_enabled = False;
107 CARD16 o_standby = 0, o_suspend = 0, o_off = 0;
108 Bool bogus_p = False;
110 if (dpms_quickoff_p && !off_secs)
112 /* To do this, we might need to temporarily re-enable DPMS first. */
116 if (standby_secs == 0 && suspend_secs == 0 && off_secs == 0)
117 /* all zero implies "DPMS disabled" */
120 else if ((standby_secs != 0 && standby_secs < 10) ||
121 (suspend_secs != 0 && suspend_secs < 10) ||
122 (off_secs != 0 && off_secs < 10))
123 /* any negative, or any positive-and-less-than-10-seconds, is crazy. */
126 if (bogus_p) enabled_p = False;
128 /* X protocol sends these values in a CARD16, so truncate them to 16 bits.
129 This means that the maximum timeout is 18:12:15.
131 if (standby_secs > 0xFFFF) standby_secs = 0xFFFF;
132 if (suspend_secs > 0xFFFF) suspend_secs = 0xFFFF;
133 if (off_secs > 0xFFFF) off_secs = 0xFFFF;
135 if (! DPMSQueryExtension (dpy, &event, &error))
138 fprintf (stderr, "%s: XDPMS extension not supported.\n", blurb());
142 if (! DPMSCapable (dpy))
145 fprintf (stderr, "%s: DPMS not supported.\n", blurb());
149 if (! DPMSInfo (dpy, &o_power, &o_enabled))
152 fprintf (stderr, "%s: unable to get DPMS state.\n", blurb());
156 if (o_enabled != enabled_p)
158 if (! (enabled_p ? DPMSEnable (dpy) : DPMSDisable (dpy)))
161 fprintf (stderr, "%s: unable to set DPMS state.\n", blurb());
165 fprintf (stderr, "%s: turned DPMS %s.\n", blurb(),
166 enabled_p ? "on" : "off");
172 fprintf (stderr, "%s: not setting bogus DPMS timeouts: %d %d %d.\n",
173 blurb(), standby_secs, suspend_secs, off_secs);
177 if (!DPMSGetTimeouts (dpy, &o_standby, &o_suspend, &o_off))
180 fprintf (stderr, "%s: unable to get DPMS timeouts.\n", blurb());
184 if (o_standby != standby_secs ||
185 o_suspend != suspend_secs ||
188 if (!DPMSSetTimeouts (dpy, standby_secs, suspend_secs, off_secs))
191 fprintf (stderr, "%s: unable to set DPMS timeouts.\n", blurb());
195 fprintf (stderr, "%s: set DPMS timeouts: %d %d %d.\n", blurb(),
196 standby_secs, suspend_secs, off_secs);
201 monitor_powered_on_p (saver_info *si)
204 int event_number, error_number;
208 if (!DPMSQueryExtension(si->dpy, &event_number, &error_number))
209 /* Server doesn't know -- assume the monitor is on. */
212 else if (!DPMSCapable(si->dpy))
213 /* Server says the monitor doesn't do power management -- so it's on. */
218 DPMSInfo(si->dpy, &state, &onoff);
220 /* Server says DPMS is disabled -- so the monitor is on. */
224 case DPMSModeOn: result = True; break; /* really on */
225 case DPMSModeStandby: result = False; break; /* kinda off */
226 case DPMSModeSuspend: result = False; break; /* pretty off */
227 case DPMSModeOff: result = False; break; /* really off */
228 default: result = True; break; /* protocol error? */
236 monitor_power_on (saver_info *si, Bool on_p)
238 if ((!!on_p) != monitor_powered_on_p (si))
240 XErrorHandler old_handler;
241 int event_number, error_number;
242 if (!DPMSQueryExtension(si->dpy, &event_number, &error_number) ||
243 !DPMSCapable(si->dpy))
245 if (si->prefs.verbose_p)
247 "%s: unable to power %s monitor: no DPMS extension.\n",
248 blurb(), (on_p ? "on" : "off"));
252 /* The manual for DPMSForceLevel() says that it throws BadMatch if
253 "DPMS is disabled on the specified display."
255 The manual for DPMSCapable() says that it "returns True if the X
256 server is capable of DPMS."
258 Apparently they consider "capable of DPMS" and "DPMS is enabled"
259 to be different things, and so even if DPMSCapable() returns
260 True, DPMSForceLevel() *might* throw an X Error. Isn't that
261 just fucking special.
263 XSync (si->dpy, False);
264 error_handler_hit_p = False;
265 old_handler = XSetErrorHandler (ignore_all_errors_ehandler);
266 XSync (si->dpy, False);
267 DPMSForceLevel(si->dpy, (on_p ? DPMSModeOn : DPMSModeOff));
268 XSync (si->dpy, False);
269 /* Ignore error_handler_hit_p, just probe monitor instead */
271 if ((!!on_p) != monitor_powered_on_p (si)) /* double-check */
273 "%s: DPMSForceLevel(dpy, %s) did not change monitor power state.\n",
275 (on_p ? "DPMSModeOn" : "DPMSModeOff"));
279 #else /* !HAVE_DPMS_EXTENSION */
282 sync_server_dpms_settings (Display *dpy, Bool enabled_p,
283 int standby_secs, int suspend_secs, int off_secs,
287 fprintf (stderr, "%s: DPMS support not compiled in.\n", blurb());
291 monitor_powered_on_p (saver_info *si)
297 monitor_power_on (saver_info *si, Bool on_p)
302 #endif /* !HAVE_DPMS_EXTENSION */