From 820af0ce4ad1cf15e42500488d19ab029776db12 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Gr=C3=A4=C3=9Flin?= <mgraesslin@kde.org>
Date: Sat, 21 Feb 2015 09:44:43 +0100
Subject: [PATCH] Guard X11 usage in InputRedirectionCursor

In kwin_wayland the InputRedirectionCursor is created before the X11
connection is established. Because of that possible usage needs to
be guarded. This is only in cursorTracking so far. The parent class
exposes whether the cursor is tracked and the doStartCursorTracking
gets invoked again when the x11Connection becomes available.
---
 cursor.cpp | 13 +++++++++++++
 cursor.h   |  6 ++++++
 2 files changed, 19 insertions(+)

diff --git a/cursor.cpp b/cursor.cpp
index 8fe4c767c3..031de0b3fe 100644
--- a/cursor.cpp
+++ b/cursor.cpp
@@ -430,6 +430,13 @@ InputRedirectionCursor::InputRedirectionCursor(QObject *parent)
 #ifndef KCMRULES
     connect(input(), &InputRedirection::keyboardModifiersChanged,
             this, &InputRedirectionCursor::slotModifiersChanged);
+    connect(kwinApp(), &Application::x11ConnectionChanged, this,
+        [this] {
+            if (isCursorTracking()) {
+                doStartCursorTracking();
+            }
+        }, Qt::QueuedConnection
+    );
 #endif
 }
 
@@ -464,12 +471,18 @@ void InputRedirectionCursor::slotPointerButtonChanged()
 
 void InputRedirectionCursor::doStartCursorTracking()
 {
+    if (!kwinApp()->x11Connection()) {
+        return;
+    }
     xcb_xfixes_select_cursor_input(connection(), rootWindow(), XCB_XFIXES_CURSOR_NOTIFY_MASK_DISPLAY_CURSOR);
     // TODO: also track the Wayland cursor
 }
 
 void InputRedirectionCursor::doStopCursorTracking()
 {
+    if (!kwinApp()->x11Connection()) {
+        return;
+    }
     xcb_xfixes_select_cursor_input(connection(), rootWindow(), 0);
     // TODO: also track the Wayland cursor
 }
diff --git a/cursor.h b/cursor.h
index 5e2342fb2a..df224e4c2e 100644
--- a/cursor.h
+++ b/cursor.h
@@ -186,6 +186,7 @@ protected:
      * to overwrite to disable platform specific code for the tracking.
      */
     virtual void doStopCursorTracking();
+    bool isCursorTracking() const;
     /**
      * Provides the actual internal cursor position to inheriting classes. If an inheriting class needs
      * access to the cursor position this method should be used instead of the static @link pos, as
@@ -295,6 +296,11 @@ inline int Cursor::themeSize() const
     return m_themeSize;
 }
 
+inline bool Cursor::isCursorTracking() const
+{
+    return m_cursorTrackingCounter > 0;
+}
+
 }
 
 #endif // KWIN_CURSOR_H