KDE4: add Qt4 glib ExcludeSocket runtime check

Add a runtime check and configure warning to disable KDE4 native
file pickers, if the Qt4 glib dispatcher doesn't honor the
QEventLoop::ExcludeSocketNotifiers flag.

This way polling the QClipboard using the event loop won't
crash LibreOffice with recursive paint events,

See https://bugreports.qt-project.org/browse/QTBUG-37380

(cherry picked from commit cc8d566d74a2e0b969b92d9cf22cc95a3bf31a98)

Change-Id: I48795deef82eaf6f95a4e518baea66c52f0b7400
Reviewed-on: https://gerrit.libreoffice.org/8708
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

9 files changed, 212 insertions, 22 deletions

diff --git a/configure.ac b/configure.ac
index 50f116224fda..f36cbaf747e2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -11126,7 +11126,7 @@ if test "$test_kde4" = "yes" -a "$ENABLE_KDE4" = "TRUE"; then
     fi
 
     qt_test_include="Qt/qobject.h"
-    qt_test_library="libQtCore.so"
+    qt_test_library="libQtNetwork.so"
     kde_test_include="kwindowsystem.h"
     kde_test_library="libsolid.so"
 
@@ -11213,8 +11213,9 @@ the root of your Qt installation by exporting QT4DIR before running "configure".
         AC_MSG_ERROR([KDE4 libraries not found.  Please specify the root of your KDE4 installation by exporting KDE4DIR before running "configure".])
     fi
 
-    KDE4_CFLAGS="`pkg-config --cflags QtCore` `pkg-config --cflags QtGui` -I$kde_incdir -DQT_CLEAN_NAMESPACE -DQT_THREAD_SUPPORT"
-    KDE4_LIBS="-L$kde_libdir -L$qt_lib_dir -lkio -lkfile -lkdeui -lkdecore -lQtCore -lQtGui"
+    PKG_CHECK_MODULES([QT4],[QtNetwork QtGui])
+    KDE4_CFLAGS="-I$kde_incdir $QT4_CFLAGS -DQT_CLEAN_NAMESPACE -DQT_THREAD_SUPPORT"
+    KDE4_LIBS="-L$kde_libdir -lkio -lkfile -lkdeui -lkdecore -L$qt_lib_dir $QT4_LIBS"
     KDE4_CFLAGS=$(printf '%s' "$KDE4_CFLAGS" | sed -e "s/-I/${ISYSTEM?}/g")
 
     AC_LANG_PUSH([C++])
@@ -11236,11 +11237,47 @@ int main(int argc, char **argv) {
     # Sets also KDE_GLIB_CFLAGS/KDE_GLIB_LIBS if successful.
     PKG_CHECK_MODULES(KDE_GLIB,[glib-2.0 >= 2.4],
         [
-        KDE_HAVE_GLIB=1
-        AC_DEFINE(KDE_HAVE_GLIB,1)
-        KDE_GLIB_CFLAGS=$(printf '%s' "$KDE_GLIB_CFLAGS" | sed -e "s/-I/${ISYSTEM?}/g")
+            KDE_HAVE_GLIB=1
+            AC_DEFINE(KDE_HAVE_GLIB,1)
+            KDE_GLIB_CFLAGS=$(printf '%s' "$KDE_GLIB_CFLAGS" | sed -e "s/-I/${ISYSTEM?}/g")
+
+            AC_LANG_PUSH([C++])
+            save_CXXFLAGS=$CXXFLAGS
+            CXXFLAGS="$CXXFLAGS $KDE4_CFLAGS"
+            save_LIBS=$LIBS
+            LIBS="$LIBS $KDE4_LIBS"
+            AC_MSG_CHECKING([whether Qt has fixed ExcludeSocketNotifiers])
+
+            # Prepare meta object data
+            TSTBASE="tst_exclude_socket_notifiers"
+            TSTMOC="${SRC_ROOT}/vcl/unx/kde4/${TSTBASE}"
+            ln -fs "${TSTMOC}.hxx"
+            $MOC4 "${TSTBASE}.hxx" -o "${TSTBASE}.moc"
+
+            AC_RUN_IFELSE([AC_LANG_SOURCE([[
+#include "tst_exclude_socket_notifiers.moc"
+
+int main(int argc, char *argv[])
+{
+    QCoreApplication app(argc, argv);
+    exit(tst_processEventsExcludeSocket());
+    return 0;
+}
+            ]])],[
+                AC_MSG_RESULT([yes])
+            ],[
+                AC_MSG_RESULT([no])
+                AC_MSG_WARN([native KDE4 file pickers will be disabled at runtime - fix your Qt4 library!])
+            ])
+
+            # Remove meta object data
+            rm -f "${TSTBASE}."*
+
+            LIBS=$save_LIBS
+            CXXFLAGS=$save_CXXFLAGS
+            AC_LANG_POP([C++])
         ],
-        AC_MSG_WARN([[No Glib found, KDE4 support will not integrate with Qt's Glib event loop support]]))
+        AC_MSG_WARN([[No Glib found, KDE4 support will not use native file pickers!]]))
 fi
 AC_SUBST(KDE4_CFLAGS)
 AC_SUBST(KDE4_LIBS)
diff --git a/vcl/CustomTarget_kde4_moc.mk b/vcl/CustomTarget_kde4_moc.mk
index 0846b0b7f261..9e417548da4b 100644
--- a/vcl/CustomTarget_kde4_moc.mk
+++ b/vcl/CustomTarget_kde4_moc.mk
@@ -11,7 +11,8 @@ $(eval $(call gb_CustomTarget_CustomTarget,vcl/unx/kde4))
 
 $(call gb_CustomTarget_get_target,vcl/unx/kde4) : \
 	$(call gb_CustomTarget_get_workdir,vcl/unx/kde4)/KDEXLib.moc \
-	$(call gb_CustomTarget_get_workdir,vcl/unx/kde4)/KDE4FilePicker.moc
+	$(call gb_CustomTarget_get_workdir,vcl/unx/kde4)/KDE4FilePicker.moc \
+	$(call gb_CustomTarget_get_workdir,vcl/unx/kde4)/tst_exclude_socket_notifiers.moc
 
 $(call gb_CustomTarget_get_workdir,vcl/unx/kde4)/%.moc : \
 		$(SRCDIR)/vcl/unx/kde4/%.hxx \
diff --git a/vcl/Library_vclplug_kde4.mk b/vcl/Library_vclplug_kde4.mk
index c72fe004d727..18ffa02dc183 100644
--- a/vcl/Library_vclplug_kde4.mk
+++ b/vcl/Library_vclplug_kde4.mk
@@ -76,7 +76,7 @@ endif
 
 $(eval $(call gb_Library_add_exception_objects,vclplug_kde4,\
     vcl/unx/kde4/KDEData \
-	vcl/unx/kde4/KDE4FilePicker \
+    vcl/unx/kde4/KDE4FilePicker \
     vcl/unx/kde4/KDESalDisplay \
     vcl/unx/kde4/KDESalFrame \
     vcl/unx/kde4/KDESalGraphics \
diff --git a/vcl/unx/kde4/KDE4FilePicker.cxx b/vcl/unx/kde4/KDE4FilePicker.cxx
index b3fde26b90a2..1cb146002236 100644
--- a/vcl/unx/kde4/KDE4FilePicker.cxx
+++ b/vcl/unx/kde4/KDE4FilePicker.cxx
@@ -261,8 +261,12 @@ sal_Int16 SAL_CALL KDE4FilePicker::execute()
     _dialog->filterWidget()->setEditable(false);
 
     // We're entering a nested loop.
-    // Release the yield mutex to prevent deadlocks.
-    int result = _dialog->exec();
+    int result;
+    {
+        // Release the yield mutex to prevent deadlocks.
+        SalYieldMutexReleaser aReleaser;
+        result = _dialog->exec();
+    }
 
     // HACK: KFileDialog uses KConfig("kdeglobals") for saving some settings
     // (such as the auto-extension flag), but that doesn't update KGlobal::config()
diff --git a/vcl/unx/kde4/KDEData.cxx b/vcl/unx/kde4/KDEData.cxx
index ccbbd9998320..0e87c6209cf6 100644
--- a/vcl/unx/kde4/KDEData.cxx
+++ b/vcl/unx/kde4/KDEData.cxx
@@ -27,6 +27,7 @@
 #include "KDEData.hxx"
 
 #include "KDEXLib.hxx"
+#include "KDESalDisplay.hxx"
 
 
 KDEData::~KDEData()
@@ -37,6 +38,7 @@ void KDEData::Init()
 {
     pXLib_ = new KDEXLib();
     pXLib_->Init();
+    SetDisplay( SalKDEDisplay::self() );
 }
 
 void KDEData::initNWF()
diff --git a/vcl/unx/kde4/KDESalInstance.cxx b/vcl/unx/kde4/KDESalInstance.cxx
index 9670172e216e..023d79051741 100644
--- a/vcl/unx/kde4/KDESalInstance.cxx
+++ b/vcl/unx/kde4/KDESalInstance.cxx
@@ -32,10 +32,14 @@ SalFrame* KDESalInstance::CreateFrame( SalFrame *pParent, sal_uLong nState )
 }
 
 uno::Reference< ui::dialogs::XFilePicker2 > KDESalInstance::createFilePicker(
-        const uno::Reference< uno::XComponentContext >& xMSF )
+    const uno::Reference< uno::XComponentContext >& xMSF )
 {
-    return uno::Reference< ui::dialogs::XFilePicker2 >(
-        static_cast<KDEXLib*>( mpXLib )->createFilePicker(xMSF) );
+    KDEXLib* kdeXLib = static_cast<KDEXLib*>( mpXLib );
+    if (kdeXLib->haveQt4SocketExcludeFix())
+        return uno::Reference< ui::dialogs::XFilePicker2 >(
+            kdeXLib->createFilePicker(xMSF) );
+    else
+        return X11SalInstance::createFilePicker( xMSF );
 }
 
 int KDESalInstance::getFrameWidth()
diff --git a/vcl/unx/kde4/KDEXLib.cxx b/vcl/unx/kde4/KDEXLib.cxx
index 5c4cd10f01e3..820d39aa661e 100644
--- a/vcl/unx/kde4/KDEXLib.cxx
+++ b/vcl/unx/kde4/KDEXLib.cxx
@@ -19,7 +19,6 @@
 
 #include "VCLKDEApplication.hxx"
 
-#include "KDE4FilePicker.hxx"
 #include "KDESalInstance.hxx"
 
 #include <kapplication.h>
@@ -45,15 +44,17 @@
 
 #include <config_kde4.h>
 
+#if KDE_HAVE_GLIB
+#include "KDE4FilePicker.hxx"
+#include "tst_exclude_socket_notifiers.moc"
+#endif
+
 KDEXLib::KDEXLib() :
     SalXLib(),  m_bStartupDone(false), m_pApplication(0),
     m_pFreeCmdLineArgs(0), m_pAppCmdLineArgs(0), m_nFakeCmdLineArgs( 0 ),
-    m_frameWidth( -1 ), m_isGlibEventLoopType(false)
+    m_frameWidth( -1 ), m_isGlibEventLoopType(false),
+    m_haveQt4SocketExcludeFix(false)
 {
-#if KDE_HAVE_GLIB
-    m_isGlibEventLoopType = QAbstractEventDispatcher::instance()->inherits( "QEventDispatcherGlib" );
-#endif
-
     // the timers created here means they belong to the main thread.
     // As the timeoutTimer runs the LO event queue, which may block on a dialog,
     // the timer has to use a Qt::QueuedConnection, otherwise the nested event
@@ -168,6 +169,14 @@ void KDEXLib::Init()
     m_pApplication = new VCLKDEApplication();
     kapp->disableSessionManagement();
     KApplication::setQuitOnLastWindowClosed(false);
+
+#if KDE_HAVE_GLIB
+    m_isGlibEventLoopType = QAbstractEventDispatcher::instance()->inherits( "QEventDispatcherGlib" );
+    if (m_isGlibEventLoopType && (0 == tst_processEventsExcludeSocket()))
+        // See http://bugreports.qt.nokia.com/browse/QTBUG-37380
+        m_haveQt4SocketExcludeFix = true;
+#endif
+
     setupEventLoop();
 
     Display* pDisp = QX11Info::display();
@@ -188,9 +197,8 @@ void KDEXLib::Init()
 #include <glib.h>
 
 static GPollFunc old_gpoll = NULL;
-static gint gpoll_wrapper( GPollFD*, guint, gint );
 
-gint gpoll_wrapper( GPollFD* ufds, guint nfds, gint timeout )
+static gint gpoll_wrapper( GPollFD* ufds, guint nfds, gint timeout )
 {
     SalYieldMutexReleaser release; // release YieldMutex (and re-acquire at block end)
     return old_gpoll( ufds, nfds, timeout );
@@ -215,6 +223,8 @@ void KDEXLib::setupEventLoop()
     {
         old_gpoll = g_main_context_get_poll_func( NULL );
         g_main_context_set_poll_func( NULL, gpoll_wrapper );
+        if( m_haveQt4SocketExcludeFix )
+            m_pApplication->clipboard()->setProperty( "useEventLoopWhenWaiting", true );
         return;
     }
 #endif
@@ -367,11 +377,15 @@ using namespace com::sun::star;
 uno::Reference< ui::dialogs::XFilePicker2 > KDEXLib::createFilePicker(
         const uno::Reference< uno::XComponentContext >& xMSF )
 {
+#if KDE_HAVE_GLIB
     if( qApp->thread() != QThread::currentThread()) {
         SalYieldMutexReleaser aReleaser;
         return Q_EMIT createFilePickerSignal( xMSF );
     }
     return uno::Reference< ui::dialogs::XFilePicker2 >( new KDE4FilePicker( xMSF ) );
+#else
+    return NULL;
+#endif
 }
 
 #define Region QtXRegion
diff --git a/vcl/unx/kde4/KDEXLib.hxx b/vcl/unx/kde4/KDEXLib.hxx
index f26948d48e14..a88258c5985e 100644
--- a/vcl/unx/kde4/KDEXLib.hxx
+++ b/vcl/unx/kde4/KDEXLib.hxx
@@ -53,6 +53,7 @@ class KDEXLib : public QObject, public SalXLib
         QTimer userEventTimer;
         int m_frameWidth;
         bool m_isGlibEventLoopType;
+        bool m_haveQt4SocketExcludeFix;
 
     private:
         void setupEventLoop();
@@ -87,6 +88,7 @@ class KDEXLib : public QObject, public SalXLib
         virtual void PostUserEvent();
 
         void doStartup();
+        bool haveQt4SocketExcludeFix() { return m_haveQt4SocketExcludeFix; }
 
     public Q_SLOTS:
         com::sun::star::uno::Reference< com::sun::star::ui::dialogs::XFilePicker2 >
diff --git a/vcl/unx/kde4/tst_exclude_socket_notifiers.hxx b/vcl/unx/kde4/tst_exclude_socket_notifiers.hxx
new file mode 100644
index 000000000000..0c874fd7147d
--- /dev/null
+++ b/vcl/unx/kde4/tst_exclude_socket_notifiers.hxx
@@ -0,0 +1,126 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ *
+ * This code is based on the SocketEventsTester from the Qt4 test suite.
+ */
+
+#pragma once
+
+#include <qcoreapplication.h>
+#include <qeventloop.h>
+#include <qthread.h>
+#include <qtimer.h>
+#include <QtNetwork/qtcpserver.h>
+#include <QtNetwork/qtcpsocket.h>
+
+class SocketEventsTester: public QObject
+{
+    Q_OBJECT
+public:
+    SocketEventsTester()
+    {
+        socket = 0;
+        server = 0;
+        dataSent = false;
+        testResult = false;
+        dataArrived = false;
+    }
+    ~SocketEventsTester()
+    {
+        delete socket;
+        delete server;
+    }
+    bool init()
+    {
+        bool ret = false;
+        server = new QTcpServer();
+        socket = new QTcpSocket();
+        connect(server, SIGNAL(newConnection()), this, SLOT(sendHello()));
+        connect(socket, SIGNAL(readyRead()), this, SLOT(sendAck()), Qt::DirectConnection);
+        if((ret = server->listen(QHostAddress::LocalHost, 0))) {
+            socket->connectToHost(server->serverAddress(), server->serverPort());
+            socket->waitForConnected();
+        }
+        return ret;
+    }
+
+    QTcpSocket *socket;
+    QTcpServer *server;
+    bool dataSent;
+    bool testResult;
+    bool dataArrived;
+public slots:
+    void sendAck()
+    {
+        dataArrived = true;
+    }
+    void sendHello()
+    {
+        char data[10] ="HELLO";
+        qint64 size = sizeof(data);
+
+        QTcpSocket *serverSocket = server->nextPendingConnection();
+        serverSocket->write(data, size);
+        dataSent = serverSocket->waitForBytesWritten(-1);
+        QEventLoop loop;
+        //allow the TCP/IP stack time to loopback the data, so our socket is ready to read
+        QTimer::singleShot(200, &loop, SLOT(quit()));
+        loop.exec(QEventLoop::ExcludeSocketNotifiers);
+        testResult = dataArrived;
+        //check the deferred event is processed
+        QTimer::singleShot(200, &loop, SLOT(quit()));
+        loop.exec();
+        serverSocket->close();
+        QThread::currentThread()->exit(0);
+    }
+};
+
+class SocketTestThread : public QThread
+{
+    Q_OBJECT
+public:
+    SocketTestThread():QThread(0),testResult(false){};
+    void run()
+    {
+        SocketEventsTester *tester = new SocketEventsTester();
+        if (tester->init())
+            exec();
+        dataSent = tester->dataSent;
+        testResult = tester->testResult;
+        dataArrived = tester->dataArrived;
+        delete tester;
+    }
+    bool dataSent;
+    bool testResult;
+    bool dataArrived;
+};
+
+#define QVERIFY(a) \
+    if (!a) return 1;
+
+static int tst_processEventsExcludeSocket()
+{
+    SocketTestThread thread;
+    thread.start();
+    QVERIFY(thread.wait());
+    QVERIFY(thread.dataSent);
+    QVERIFY(!thread.testResult);
+    QVERIFY(thread.dataArrived);
+    return 0;
+}
+