+
+\f
+/* Display Power Management System (DPMS.)
+
+ On XFree86 systems, "man xset" reports:
+
+ -dpms The -dpms option disables DPMS (Energy Star) features.
+ +dpms The +dpms option enables DPMS (Energy Star) features.
+
+ dpms flags...
+ The dpms option allows the DPMS (Energy Star)
+ parameters to be set. The option can take up to three
+ numerical values, or the `force' flag followed by a
+ DPMS state. The `force' flags forces the server to
+ immediately switch to the DPMS state specified. The
+ DPMS state can be one of `standby', `suspend', or
+ `off'. When numerical values are given, they set the
+ inactivity period before the three modes are activated.
+ The first value given is for the `standby' mode, the
+ second is for the `suspend' mode, and the third is for
+ the `off' mode. Setting these values implicitly
+ enables the DPMS features. A value of zero disables a
+ particular mode.
+
+ However, note that the implementation is more than a little bogus,
+ in that there is code in /usr/X11R6/lib/libXdpms.a to implement all
+ the usual server-extension-querying utilities -- but there are no
+ prototypes in any header file! Thus, the prototypes here. (The
+ stuff in X11/extensions/dpms.h and X11/extensions/dpmsstr.h define
+ the raw X protcol, they don't define the API to libXdpms.a.)
+
+ Some documentation:
+ Library: ftp://ftp.x.org/pub/R6.4/xc/doc/specs/Xext/DPMSLib.ms
+ Protocol: ftp://ftp.x.org/pub/R6.4/xc/doc/specs/Xext/DPMS.ms
+ */
+
+#ifdef HAVE_DPMS_EXTENSION
+
+#include <X11/Xproto.h> /* for CARD16 */
+#include <X11/extensions/dpms.h>
+#include <X11/extensions/dpmsstr.h>
+
+extern Bool DPMSQueryExtension (Display *dpy, int *event_ret, int *error_ret);
+extern Bool DPMSCapable (Display *dpy);
+extern Status DPMSForceLevel (Display *dpy, CARD16 level);
+extern Status DPMSInfo (Display *dpy, CARD16 *power_level, BOOL *state);
+
+#if 0 /* others we don't use */
+extern Status DPMSGetVersion (Display *dpy, int *major_ret, int *minor_ret);
+extern Status DPMSSetTimeouts (Display *dpy,
+ CARD16 standby, CARD16 suspend, CARD16 off);
+extern Bool DPMSGetTimeouts (Display *dpy,
+ CARD16 *standby, CARD16 *suspend, CARD16 *off);
+extern Status DPMSEnable (Display *dpy);
+extern Status DPMSDisable (Display *dpy);
+#endif /* 0 */
+
+
+Bool
+monitor_powered_on_p (saver_info *si)
+{
+ Bool result;
+ int event_number, error_number;
+ BOOL onoff = False;
+ CARD16 state;
+
+ if (!DPMSQueryExtension(si->dpy, &event_number, &error_number))
+ /* Server doesn't know -- assume the monitor is on. */
+ result = True;
+
+ else if (!DPMSCapable(si->dpy))
+ /* Server says the monitor doesn't do power management -- so it's on. */
+ result = True;
+
+ else
+ {
+ DPMSInfo(si->dpy, &state, &onoff);
+ if (!onoff)
+ /* Server says DPMS is disabled -- so the monitor is on. */
+ result = True;
+ else
+ switch (state) {
+ case DPMSModeOn: result = True; break; /* really on */
+ case DPMSModeStandby: result = False; break; /* kinda off */
+ case DPMSModeSuspend: result = False; break; /* pretty off */
+ case DPMSModeOff: result = False; break; /* really off */
+ default: result = True; break; /* protocol error? */
+ }
+ }
+
+ return result;
+}
+
+void
+monitor_power_on (saver_info *si)
+{
+ if (!monitor_powered_on_p (si))
+ {
+ DPMSForceLevel(si->dpy, DPMSModeOn);
+ XSync(si->dpy, False);
+ if (!monitor_powered_on_p (si))
+ fprintf (stderr,
+ "%s: DPMSForceLevel(dpy, DPMSModeOn) did not power the monitor on?\n",
+ blurb());
+ }
+}
+
+#else /* !HAVE_DPMS_EXTENSION */
+
+Bool
+monitor_powered_on_p (saver_info *si)
+{
+ return True;
+}
+
+void
+monitor_power_on (saver_info *si)
+{
+ return;
+}
+
+#endif /* !HAVE_DPMS_EXTENSION */