6 files changed, 62 insertions, 7 deletions

diff --git a/src/plugins/platforms/xcb/qxcbconnection.cpp b/src/plugins/platforms/xcb/qxcbconnection.cpp
index 40e35acd5e..c4dd58667d 100644
--- a/src/plugins/platforms/xcb/qxcbconnection.cpp
+++ b/src/plugins/platforms/xcb/qxcbconnection.cpp
@@ -1232,6 +1232,7 @@ static const char * xcb_atomnames = {
     // ICCCM window state
     "WM_STATE\0"
     "WM_CHANGE_STATE\0"
+    "WM_CLASS\0"
 
     // Session management
     "WM_CLIENT_LEADER\0"
diff --git a/src/plugins/platforms/xcb/qxcbconnection.h b/src/plugins/platforms/xcb/qxcbconnection.h
index 1662e862f1..8f568c6c25 100644
--- a/src/plugins/platforms/xcb/qxcbconnection.h
+++ b/src/plugins/platforms/xcb/qxcbconnection.h
@@ -102,6 +102,7 @@ namespace QXcbAtom {
         // ICCCM window state
         WM_STATE,
         WM_CHANGE_STATE,
+        WM_CLASS,
 
         // Session management
         WM_CLIENT_LEADER,
diff --git a/src/plugins/platforms/xcb/qxcbintegration.cpp b/src/plugins/platforms/xcb/qxcbintegration.cpp
index 1c170d44e6..46077e2c3f 100644
--- a/src/plugins/platforms/xcb/qxcbintegration.cpp
+++ b/src/plugins/platforms/xcb/qxcbintegration.cpp
@@ -389,4 +389,48 @@ QVariant QXcbIntegration::styleHint(QPlatformIntegration::StyleHint hint) const
     return QPlatformIntegration::styleHint(hint);
 }
 
+static QString argv0BaseName()
+{
+    QString result;
+    const QStringList arguments = QCoreApplication::arguments();
+    if (!arguments.isEmpty() && !arguments.front().isEmpty()) {
+        result = arguments.front();
+        const int lastSlashPos = result.lastIndexOf(QLatin1Char('/'));
+        if (lastSlashPos != -1)
+            result.remove(0, lastSlashPos + 1);
+    }
+    return result;
+}
+
+static const char resourceNameVar[] = "RESOURCE_NAME";
+
+QByteArray QXcbIntegration::wmClass() const
+{
+    if (m_wmClass.isEmpty()) {
+        // Instance name according to ICCCM 4.1.2.5
+        QString name;
+        if (name.isEmpty() && qEnvironmentVariableIsSet(resourceNameVar))
+            name = QString::fromLocal8Bit(qgetenv(resourceNameVar));
+        if (name.isEmpty())
+            name = argv0BaseName();
+
+        // Note: QCoreApplication::applicationName() cannot be called from the QGuiApplication constructor,
+        // hence this delayed initialization.
+        QString className = QCoreApplication::applicationName();
+        if (className.isEmpty()) {
+            className = argv0BaseName();
+            if (!className.isEmpty() && className.at(0).isLower())
+                className[0] = className.at(0).toUpper();
+        }
+
+        if (!name.isEmpty() && !className.isEmpty()) {
+            m_wmClass = name.toLocal8Bit();
+            m_wmClass.append('\0');
+            m_wmClass.append(className.toLocal8Bit());
+            m_wmClass.append('\0');
+        }
+    }
+    return m_wmClass;
+}
+
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/xcb/qxcbintegration.h b/src/plugins/platforms/xcb/qxcbintegration.h
index cc39fb1462..b884b3b7f2 100644
--- a/src/plugins/platforms/xcb/qxcbintegration.h
+++ b/src/plugins/platforms/xcb/qxcbintegration.h
@@ -99,6 +99,8 @@ public:
 
     QXcbConnection *defaultConnection() const { return m_connections.first(); }
 
+    QByteArray wmClass() const;
+
 private:
     QList<QXcbConnection *> m_connections;
 
@@ -115,6 +117,8 @@ private:
     QScopedPointer<QPlatformServices> m_services;
 
     friend class QXcbConnection; // access QPlatformIntegration::screenAdded()
+
+    mutable QByteArray m_wmClass;
 };
 
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/xcb/qxcbnativeinterface.cpp b/src/plugins/platforms/xcb/qxcbnativeinterface.cpp
index 7d832a1c08..9e9fd2914f 100644
--- a/src/plugins/platforms/xcb/qxcbnativeinterface.cpp
+++ b/src/plugins/platforms/xcb/qxcbnativeinterface.cpp
@@ -95,12 +95,9 @@ QXcbNativeInterface::QXcbNativeInterface() :
 
 void QXcbNativeInterface::beep() // For QApplication::beep()
 {
-#ifdef XCB_USE_XLIB
-    ::Display *display = (::Display *)nativeResourceForScreen(QByteArrayLiteral("display"), QGuiApplication::primaryScreen());
-    XBell(display, 0);
-#else
-    fputc(7, stdout);
-#endif
+    QPlatformScreen *screen = QGuiApplication::primaryScreen()->handle();
+    xcb_connection_t *connection = static_cast<QXcbScreen *>(screen)->xcb_connection();
+    xcb_bell(connection, 0);
 }
 
 void *QXcbNativeInterface::nativeResourceForIntegration(const QByteArray &resourceString)
diff --git a/src/plugins/platforms/xcb/qxcbwindow.cpp b/src/plugins/platforms/xcb/qxcbwindow.cpp
index 3a19788316..0325338a13 100644
--- a/src/plugins/platforms/xcb/qxcbwindow.cpp
+++ b/src/plugins/platforms/xcb/qxcbwindow.cpp
@@ -379,6 +379,13 @@ void QXcbWindow::create()
     m_syncValue.hi = 0;
     m_syncValue.lo = 0;
 
+    const QByteArray wmClass = static_cast<QXcbIntegration *>(QGuiApplicationPrivate::platformIntegration())->wmClass();
+    if (!wmClass.isEmpty()) {
+        Q_XCB_CALL(xcb_change_property(xcb_connection(), XCB_PROP_MODE_REPLACE,
+                                       m_window, atom(QXcbAtom::WM_CLASS),
+                                       XCB_ATOM_STRING, 8, wmClass.size(), wmClass.constData()));
+    }
+
     if (m_usingSyncProtocol) {
         m_syncCounter = xcb_generate_id(xcb_connection());
         Q_XCB_CALL(xcb_sync_create_counter(xcb_connection(), m_syncCounter, m_syncValue));
@@ -1636,7 +1643,8 @@ void QXcbWindow::handleButtonPressEvent(const xcb_button_press_event_t *event)
 {
     if (window() != QGuiApplication::focusWindow()) {
         QWindow *w = static_cast<QWindowPrivate *>(QObjectPrivate::get(window()))->eventReceiver();
-        w->requestActivate();
+        if (!(w->flags() & Qt::WindowDoesNotAcceptFocus))
+            w->requestActivate();
     }
 
     updateNetWmUserTime(event->time);