From 675d3548153223c6658fc4a84f252736846a0874 Mon Sep 17 00:00:00 2001
From: Paul Olav Tvete <paul.tvete@digia.com>
Date: Wed, 27 Aug 2014 15:40:42 +0200
Subject: [PATCH] Avoid deadlock when suspending device

Don't wait for the GUI thread when it's already waiting for us.

An application that uses the virtual keyboard may get an inputmethod
query just when it is being suspended. If the GUI thread is already
blocking on a semaphore at that point, waiting for the android thread,
we really do not want to wait for the GUI thread...

Task-number: QTBUG-40955
Change-Id: Iea2cf0dd058a41a897d596c4bcf16f0508adb20b
Reviewed-by: Christian Stromme <christian.stromme@digia.com>
---
 src/plugins/platforms/android/qandroidinputcontext.cpp | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/plugins/platforms/android/qandroidinputcontext.cpp b/src/plugins/platforms/android/qandroidinputcontext.cpp
index 5d47d2fda4..90eff615a2 100644
--- a/src/plugins/platforms/android/qandroidinputcontext.cpp
+++ b/src/plugins/platforms/android/qandroidinputcontext.cpp
@@ -45,6 +45,7 @@
 #include "qandroidinputcontext.h"
 #include "androidjnimain.h"
 #include "androidjniinput.h"
+#include "qandroideventdispatcher.h"
 #include <QDebug>
 #include <qevent.h>
 #include <qguiapplication.h>
@@ -995,8 +996,10 @@ Q_INVOKABLE QVariant QAndroidInputContext::queryFocusObjectUnsafe(Qt::InputMetho
 
 QVariant QAndroidInputContext::queryFocusObjectThreadSafe(Qt::InputMethodQuery query, QVariant argument)
 {
-    bool inMainThread = qGuiApp->thread() == QThread::currentThread();
+    const bool inMainThread = qGuiApp->thread() == QThread::currentThread();
     QVariant retval;
+    if (QAndroidEventDispatcherStopper::stopped() && !inMainThread)
+        return retval;
 
     QMetaObject::invokeMethod(this, "queryFocusObjectUnsafe",
                               inMainThread ? Qt::DirectConnection : Qt::BlockingQueuedConnection,
@@ -1010,12 +1013,15 @@ QVariant QAndroidInputContext::queryFocusObjectThreadSafe(Qt::InputMethodQuery q
 QSharedPointer<QInputMethodQueryEvent> QAndroidInputContext::focusObjectInputMethodQuery(Qt::InputMethodQueries queries)
 {
 #warning TODO make qGuiApp->focusObject() thread safe !!!
+    const bool inMainThread = qGuiApp->thread() == QThread::currentThread();
+    if (QAndroidEventDispatcherStopper::stopped() && !inMainThread)
+        return QSharedPointer<QInputMethodQueryEvent>();
     QObject *focusObject = qGuiApp->focusObject();
     if (!focusObject)
         return QSharedPointer<QInputMethodQueryEvent>();
 
     QSharedPointer<QInputMethodQueryEvent> ret = QSharedPointer<QInputMethodQueryEvent>(new QInputMethodQueryEvent(queries));
-    if (qGuiApp->thread()==QThread::currentThread()) {
+    if (inMainThread) {
         QCoreApplication::sendEvent(focusObject, ret.data());
     } else {
         QMetaObject::invokeMethod(this,