[server] Prevent screen standby while clients are connected

2 files changed, 100 insertions, 0 deletions

diff --git a/src/server/util/platform/screensaver.h b/src/server/util/platform/screensaver.h
new file mode 100644
index 0000000..d62f9e1
--- /dev/null
+++ b/src/server/util/platform/screensaver.h
@@ -0,0 +1,26 @@
+#ifndef SCREENSAVER_H_
+#define SCREENSAVER_H_
+
+namespace ScreenSaver {
+
+	/**
+	 * Whether we want to allow the screen saver
+	 * to activate or the screen to enter standby.
+	 * Note: If the screen is already in standby,
+	 * this will not power it on again, or disable
+	 * the screen saver, so to be safe, you might
+	 * want to call forceOn() too.
+	 * @param allow true to allow ss/standby
+	 */
+	void allowSaverAndStandby(bool allow);
+
+	/**
+	 * Disable the screen saver (only if password
+	 * locking is disabled!), power screen on if
+	 * it's in standby.
+	 */
+	void forceUnlockAndScreenOn();
+
+}
+
+#endif /* SCREENSAVER_H_ */
diff --git a/src/server/util/platform/screensaver_X11.cpp b/src/server/util/platform/screensaver_X11.cpp
new file mode 100644
index 0000000..efffba9
--- /dev/null
+++ b/src/server/util/platform/screensaver_X11.cpp
@@ -0,0 +1,74 @@
+#include "screensaver.h"
+
+#include <QX11Info>
+#include <QStringList>
+#include <QProcess>
+#include <X11/Xlib.h>
+
+#ifdef X11_Xscreensaver_FOUND
+#	include <X11/extensions/scrnsaver.h>
+#endif
+#ifdef X11_dpms_FOUND
+#include <X11/extensions/dpms.h>
+#endif
+
+namespace {
+
+	Display *display = NULL;
+	bool extensionSupported = false;
+	bool dpmsSupported = false;
+
+	bool init()
+	{
+		if (display != NULL) {
+			return true;
+		}
+		display = QX11Info::display();
+		if (display == NULL) {
+			return false;
+		}
+#ifdef X11_Xscreensaver_FOUND
+		int dummy;
+		extensionSupported = (XScreenSaverQueryExtension(display, &dummy, &dummy) == True);
+#endif
+#ifdef X11_dpms_FOUND
+		dpmsSupported = (DPMSCapable(display) == True);
+#endif
+		return true;
+	}
+
+}
+
+namespace ScreenSaver {
+
+	void allowSaverAndStandby(bool allow)
+	{
+		if (!init())
+			return;
+#ifdef X11_Xscreensaver_FOUND
+		if (extensionSupported) {
+			XScreenSaverSuspend(display, allow ? False : True);
+			return;
+		}
+#endif
+		// TODO: Maybe try some fallback, call xset, or trigger some event periodically
+	}
+
+	void forceUnlockAndScreenOn()
+	{
+		if (!init())
+			return;
+		QProcess process;
+		process.start("xscreensaver-command", QStringList() << "-deactivate");
+		process.waitForFinished(100);
+#ifdef X11_dpms_FOUND
+		CARD16 power_level;
+		BOOL state;
+		if (DPMSInfo(display, &power_level, &state) && state) {
+			DPMSForceLevel(display, DPMSModeOn);
+			return;
+		}
+#endif
+	}
+
+}