From 3a2ece17c3ddcfba584cfdf90482a260d7e9c3ee Mon Sep 17 00:00:00 2001
From: Tomasz Olszak <olszak.tomasz@gmail.com>
Date: Tue, 14 Jan 2014 21:29:08 +0100
Subject: [PATCH] Don't flushWindowSystemEvents in QWaylandWindow ctor.

tests/auto/gui/kernel/qbackingstore test crashed because the
flush in QWaylandWindow::setWindowState invoked backing store
expose event handling which in turn tried to use related
(not yet created) QWaylandWindow.

Change-Id: Ic9f29cc3433e6e671deb756aebe26530ebc72042
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>
---
 .../platforms/wayland/qwaylandwindow.cpp      | 58 ++++++++++---------
 .../platforms/wayland/qwaylandwindow_p.h      |  2 +
 2 files changed, 34 insertions(+), 26 deletions(-)

diff --git a/src/plugins/platforms/wayland/qwaylandwindow.cpp b/src/plugins/platforms/wayland/qwaylandwindow.cpp
index 810239a7b7a..3c7b2eac165 100644
--- a/src/plugins/platforms/wayland/qwaylandwindow.cpp
+++ b/src/plugins/platforms/wayland/qwaylandwindow.cpp
@@ -119,7 +119,7 @@ QWaylandWindow::QWaylandWindow(QWindow *window)
 
     setWindowFlags(window->flags());
     setGeometry(window->geometry());
-    setWindowState(window->windowState());
+    setWindowStateInternal(window->windowState());
 }
 
 QWaylandWindow::~QWaylandWindow()
@@ -409,31 +409,8 @@ void QWaylandWindow::handleContentOrientationChange(Qt::ScreenOrientation orient
 
 void QWaylandWindow::setWindowState(Qt::WindowState state)
 {
-    if (mState == state) {
-        return;
-    }
-
-    // As of february 2013 QWindow::setWindowState sets the new state value after
-    // QPlatformWindow::setWindowState returns, so we cannot rely on QWindow::windowState
-    // here. We use then this mState variable.
-    mState = state;
-    createDecoration();
-    switch (state) {
-        case Qt::WindowFullScreen:
-            mShellSurface->setFullscreen();
-            break;
-        case Qt::WindowMaximized:
-            mShellSurface->setMaximized();
-            break;
-        case Qt::WindowMinimized:
-            mShellSurface->setMinimized();
-            break;
-        default:
-            mShellSurface->setNormal();
-    }
-
-    QWindowSystemInterface::handleWindowStateChanged(window(), mState);
-    QWindowSystemInterface::flushWindowSystemEvents(); // Required for oldState to work on WindowStateChanged
+    if (setWindowStateInternal(state))
+        QWindowSystemInterface::flushWindowSystemEvents(); // Required for oldState to work on WindowStateChanged
 }
 
 void QWaylandWindow::setWindowFlags(Qt::WindowFlags flags)
@@ -605,4 +582,33 @@ bool QWaylandWindow::setMouseGrabEnabled(bool grab)
     return true;
 }
 
+bool QWaylandWindow::setWindowStateInternal(Qt::WindowState state)
+{
+    if (mState == state) {
+        return false;
+    }
+
+    // As of february 2013 QWindow::setWindowState sets the new state value after
+    // QPlatformWindow::setWindowState returns, so we cannot rely on QWindow::windowState
+    // here. We use then this mState variable.
+    mState = state;
+    createDecoration();
+    switch (state) {
+        case Qt::WindowFullScreen:
+            mShellSurface->setFullscreen();
+            break;
+        case Qt::WindowMaximized:
+            mShellSurface->setMaximized();
+            break;
+        case Qt::WindowMinimized:
+            mShellSurface->setMinimized();
+            break;
+        default:
+            mShellSurface->setNormal();
+    }
+
+    QWindowSystemInterface::handleWindowStateChanged(window(), mState);
+    return true;
+}
+
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/wayland/qwaylandwindow_p.h b/src/plugins/platforms/wayland/qwaylandwindow_p.h
index 6078dab7f6e..e99e31bdf63 100644
--- a/src/plugins/platforms/wayland/qwaylandwindow_p.h
+++ b/src/plugins/platforms/wayland/qwaylandwindow_p.h
@@ -204,6 +204,8 @@ protected:
     Qt::WindowState mState;
 
 private:
+    bool setWindowStateInternal(Qt::WindowState flags);
+
     void handleMouseEventWithDecoration(QWaylandInputDevice *inputDevice,
                                         ulong timestamp,
                                         const QPointF & local,