[server] Only block screen saver from running when first client connects

The screen saver lock is recursive, so if we call it for every client
that connects, but only unlock once when the last client disconnects, the
screen saver will be blocked forever.
Fixes #3083

1 files changed, 5 insertions, 1 deletions

diff --git a/src/server/mainwindow/mainwindow.cpp b/src/server/mainwindow/mainwindow.cpp
index a984173..2eab581 100644
--- a/src/server/mainwindow/mainwindow.cpp
+++ b/src/server/mainwindow/mainwindow.cpp
@@ -210,12 +210,16 @@ void MainWindow::clientCountChanged()
 	_examModeLabel->setFixedHeight(e ? 400 : 0);
 
 	if (_lastClientCount != clientCount) {
+		// Client count actually changed
 		if (clientCount == 0) {
+			// Last client must have disconnected, enable screen saver again
 			ScreenSaver::allowSaverAndStandby(true);
-		} else {
+		} else if (_lastClientCount == 0) {
+			// We didn't have a client before, but now we do, disable screen saver
 			ScreenSaver::forceUnlockAndScreenOn();
 			ScreenSaver::allowSaverAndStandby(false);
 		}
+		// Remember client count
 		_lastClientCount = clientCount;
 	}
 }