checkpoint. adding screen saver support. only on X so far

and untested.  also some known problems:  not detecting an
xscreensaver started after us and not detecting built-in
screen saver activation (not sure if we can without using
ugly extensions).

server/CXWindowsPrimaryScreen.cpp

@@ -1,6 +1,7 @@
 #include "CXWindowsPrimaryScreen.h"
 #include "CServer.h"
 #include "CXWindowsClipboard.h"
+#include "CXWindowsScreenSaver.h"
 #include "CXWindowsUtil.h"
 #include "CThread.h"
 #include "CLog.h"
@@ -60,6 +61,14 @@ CXWindowsPrimaryScreen::run()
 			}
 			break;
 
+		case ClientMessage:
+			if (xevent.xclient.message_type == m_atomScreenSaver ||
+				xevent.xclient.format       == 32) {
+				// screen saver activation/deactivation event
+				m_server->onScreenSaver(xevent.xclient.data.l[0] != 0);
+			}
+			break;
+
 		case KeyPress:
 			{
 				log((CLOG_DEBUG1 "event: KeyPress code=%d, state=0x%04x", xevent.xkey.keycode, xevent.xkey.state));
@@ -267,6 +276,10 @@ CXWindowsPrimaryScreen::open(CServer* server)
 	{
 		CDisplayLock display(this);
 
+		// get notified of screen saver activation/deactivation
+		m_atomScreenSaver = XInternAtom(display, "SCREENSAVER", False);
+		getScreenSaver()->setNotify(m_window);
+
 		// update key state
 		updateModifierMap(display);
 
@@ -298,6 +311,10 @@ CXWindowsPrimaryScreen::close()
 {
 	assert(m_server != NULL);
 
+	// stop being notified of screen saver activation/deactivation
+	getScreenSaver()->setNotify(None);
+	m_atomScreenSaver = None;
+
 	// close the display
 	closeDisplay();