Check if xkb extension is present

According to docs:

"You must call XkbQueryExtension or XkbOpenDisplay
before using any other Xkb library interfaces"

Task-number: QTBUG-97472
Pick-to: 6.2
Change-Id: I84c1bc49b077224a93d9f8d7a9ac29fe089de13e
Reviewed-by: Liang Qi <liang.qi@qt.io>
Reviewed-by: Peter Varga <pvarga@inf.u-szeged.hu>

1 files changed, 6 insertions, 0 deletions

diff --git a/src/core/ozone/ozone_platform_qt.cpp b/src/core/ozone/ozone_platform_qt.cpp
index 8dbacfb2f..33d7bd992 100644
--- a/src/core/ozone/ozone_platform_qt.cpp
+++ b/src/core/ozone/ozone_platform_qt.cpp
@@ -160,6 +160,12 @@ static std::string getCurrentKeyboardLayout()
     if (dpy == nullptr)
         return std::string();
 
+    int d;
+    if (!XkbQueryExtension(dpy, &d, &d, &d, &d, &d)) {
+        // no Xkb extension
+        return std::string();
+    }
+
     XkbStateRec state;
     if (XkbGetState(dpy, XkbUseCoreKbd, &state) != 0)
         return std::string();