Pass argc, argv to the platform plugins.

Allow for parsing of X11-specific arguments like -display,
-geometry. Introduce overload of
QPlatformIntegration::create() with argc and argv
and provide default implementation that calls the old version
(for platforms that do not have argc, argv). Provide default
implementation for the old version returning 0 so that platforms
using the new API compile.
Prototypically implement -display in XCB.

Task-number: QTBUG-29396
Change-Id: I6a0e9271fad6e2d10f11b80393025ae3a3e36623
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>

9 files changed, 62 insertions, 17 deletions

diff --git a/src/gui/kernel/qguiapplication.cpp b/src/gui/kernel/qguiapplication.cpp
index 118b481fa3..a8a4ad1937 100644
--- a/src/gui/kernel/qguiapplication.cpp
+++ b/src/gui/kernel/qguiapplication.cpp
@@ -773,14 +773,14 @@ QString QGuiApplication::platformName()
            *QGuiApplicationPrivate::platform_name : QString();
 }
 
-static void init_platform(const QString &pluginArgument, const QString &platformPluginPath)
+static void init_platform(const QString &pluginArgument, const QString &platformPluginPath, int &argc, char **argv)
 {
     // Split into platform name and arguments
     QStringList arguments = pluginArgument.split(QLatin1Char(':'));
     const QString name = arguments.takeFirst().toLower();
 
    // Create the platform integration.
-    QGuiApplicationPrivate::platform_integration = QPlatformIntegrationFactory::create(name, arguments, platformPluginPath);
+    QGuiApplicationPrivate::platform_integration = QPlatformIntegrationFactory::create(name, arguments, argc, argv, platformPluginPath);
     if (QGuiApplicationPrivate::platform_integration) {
         QGuiApplicationPrivate::platform_name = new QString(name);
     } else {
@@ -908,7 +908,7 @@ void QGuiApplicationPrivate::createPlatformIntegration()
         argc = j;
     }
 
-    init_platform(QLatin1String(platformName), platformPluginPath);
+    init_platform(QLatin1String(platformName), platformPluginPath, argc, argv);
 
 }
 
diff --git a/src/gui/kernel/qplatformintegrationfactory.cpp b/src/gui/kernel/qplatformintegrationfactory.cpp
index 21f53d17de..365edd2010 100644
--- a/src/gui/kernel/qplatformintegrationfactory.cpp
+++ b/src/gui/kernel/qplatformintegrationfactory.cpp
@@ -55,18 +55,30 @@ Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, loader,
     (QPlatformIntegrationFactoryInterface_iid, QLatin1String("/platforms"), Qt::CaseInsensitive))
 Q_GLOBAL_STATIC_WITH_ARGS(QFactoryLoader, directLoader,
                           (QPlatformIntegrationFactoryInterface_iid, QLatin1String(""), Qt::CaseInsensitive))
-#endif
 
-QPlatformIntegration *QPlatformIntegrationFactory::create(const QString &platform, const QStringList &paramList, const QString &platformPluginPath)
+static inline QPlatformIntegration *loadIntegration(QFactoryLoader *loader, const QString &key, const QStringList &parameters, int &argc, char ** argv)
+{
+    const int index = loader->indexOf(key);
+    if (index != -1) {
+        if (QPlatformIntegrationPlugin *factory = qobject_cast<QPlatformIntegrationPlugin *>(loader->instance(index)))
+            if (QPlatformIntegration *result = factory->create(key, parameters, argc, argv))
+                return result;
+    }
+    return 0;
+}
+
+#endif // !QT_NO_LIBRARY
+
+QPlatformIntegration *QPlatformIntegrationFactory::create(const QString &platform, const QStringList &paramList, int &argc, char **argv, const QString &platformPluginPath)
 {
 #ifndef QT_NO_LIBRARY
     // Try loading the plugin from platformPluginPath first:
     if (!platformPluginPath.isEmpty()) {
         QCoreApplication::addLibraryPath(platformPluginPath);
-        if (QPlatformIntegration *ret = qLoadPlugin1<QPlatformIntegration, QPlatformIntegrationPlugin>(directLoader(), platform, paramList))
+        if (QPlatformIntegration *ret = loadIntegration(directLoader(), platform, paramList, argc, argv))
             return ret;
     }
-    if (QPlatformIntegration *ret = qLoadPlugin1<QPlatformIntegration, QPlatformIntegrationPlugin>(loader(), platform, paramList))
+    if (QPlatformIntegration *ret = loadIntegration(loader(), platform, paramList, argc, argv))
         return ret;
 #endif
     return 0;
diff --git a/src/gui/kernel/qplatformintegrationfactory_p.h b/src/gui/kernel/qplatformintegrationfactory_p.h
index fb3ba55316..bc8ce11609 100644
--- a/src/gui/kernel/qplatformintegrationfactory_p.h
+++ b/src/gui/kernel/qplatformintegrationfactory_p.h
@@ -64,7 +64,7 @@ class Q_GUI_EXPORT QPlatformIntegrationFactory
 {
 public:
     static QStringList keys(const QString &platformPluginPath = QString());
-    static QPlatformIntegration *create(const QString &name, const QStringList &args, const QString &platformPluginPath = QString());
+    static QPlatformIntegration *create(const QString &name, const QStringList &args, int &argc, char **argv, const QString &platformPluginPath = QString());
 };
 
 QT_END_NAMESPACE
diff --git a/src/gui/kernel/qplatformintegrationplugin.cpp b/src/gui/kernel/qplatformintegrationplugin.cpp
index 0f7f365d2a..2a9a047141 100644
--- a/src/gui/kernel/qplatformintegrationplugin.cpp
+++ b/src/gui/kernel/qplatformintegrationplugin.cpp
@@ -52,4 +52,18 @@ QPlatformIntegrationPlugin::~QPlatformIntegrationPlugin()
 {
 }
 
+QPlatformIntegration *QPlatformIntegrationPlugin::create(const QString &key, const QStringList &paramList)
+{
+    Q_UNUSED(key)
+    Q_UNUSED(paramList);
+    return 0;
+}
+
+QPlatformIntegration *QPlatformIntegrationPlugin::create(const QString &key, const QStringList &paramList, int &argc, char **argv)
+{
+    Q_UNUSED(argc)
+    Q_UNUSED(argv)
+    return create(key, paramList); // Fallback for platform plugins that do not implement the argc/argv version.
+}
+
 QT_END_NAMESPACE
diff --git a/src/gui/kernel/qplatformintegrationplugin.h b/src/gui/kernel/qplatformintegrationplugin.h
index 434366f0b0..674622f84a 100644
--- a/src/gui/kernel/qplatformintegrationplugin.h
+++ b/src/gui/kernel/qplatformintegrationplugin.h
@@ -68,7 +68,8 @@ public:
     explicit QPlatformIntegrationPlugin(QObject *parent = 0);
     ~QPlatformIntegrationPlugin();
 
-    virtual QPlatformIntegration *create(const QString &key, const QStringList &paramList) = 0;
+    virtual QPlatformIntegration *create(const QString &key, const QStringList &paramList);
+    virtual QPlatformIntegration *create(const QString &key, const QStringList &paramList, int &argc, char **argv);
 };
 
 QT_END_NAMESPACE
diff --git a/src/plugins/platforms/windows/main.cpp b/src/plugins/platforms/windows/main.cpp
index e5c3269a6c..16cac9d547 100644
--- a/src/plugins/platforms/windows/main.cpp
+++ b/src/plugins/platforms/windows/main.cpp
@@ -107,10 +107,10 @@ class QWindowsIntegrationPlugin : public QPlatformIntegrationPlugin
     Q_OBJECT
     Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.1" FILE "windows.json")
 public:
-    QPlatformIntegration *create(const QString&, const QStringList&);
+    QPlatformIntegration *create(const QString&, const QStringList&, int &, char **);
 };
 
-QPlatformIntegration *QWindowsIntegrationPlugin::create(const QString& system, const QStringList& paramList)
+QPlatformIntegration *QWindowsIntegrationPlugin::create(const QString& system, const QStringList& paramList, int &, char **)
 {
     if (system.compare(system, QStringLiteral("windows"), Qt::CaseInsensitive) == 0)
         return new QWindowsIntegration(paramList);
diff --git a/src/plugins/platforms/xcb/main.cpp b/src/plugins/platforms/xcb/main.cpp
index be5a0e3501..09e60f8d4c 100644
--- a/src/plugins/platforms/xcb/main.cpp
+++ b/src/plugins/platforms/xcb/main.cpp
@@ -49,13 +49,13 @@ class QXcbIntegrationPlugin : public QPlatformIntegrationPlugin
    Q_OBJECT
    Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.1" FILE "xcb.json")
 public:
-    QPlatformIntegration *create(const QString&, const QStringList&);
+    QPlatformIntegration *create(const QString&, const QStringList&, int &, char **);
 };
 
-QPlatformIntegration* QXcbIntegrationPlugin::create(const QString& system, const QStringList& parameters)
+QPlatformIntegration* QXcbIntegrationPlugin::create(const QString& system, const QStringList& parameters, int &argc, char **argv)
 {
     if (system.toLower() == "xcb")
-        return new QXcbIntegration(parameters);
+        return new QXcbIntegration(parameters, argc, argv);
 
     return 0;
 }
diff --git a/src/plugins/platforms/xcb/qxcbintegration.cpp b/src/plugins/platforms/xcb/qxcbintegration.cpp
index 0ff18d9c92..1c170d44e6 100644
--- a/src/plugins/platforms/xcb/qxcbintegration.cpp
+++ b/src/plugins/platforms/xcb/qxcbintegration.cpp
@@ -119,7 +119,7 @@ static bool runningUnderDebugger()
 }
 #endif
 
-QXcbIntegration::QXcbIntegration(const QStringList &parameters)
+QXcbIntegration::QXcbIntegration(const QStringList &parameters, int &argc, char **argv)
     : m_eventDispatcher(createUnixEventDispatcher())
     ,  m_services(new QGenericUnixServices)
 {
@@ -138,7 +138,25 @@ QXcbIntegration::QXcbIntegration(const QStringList &parameters)
     if (canNotGrabEnv)
         canGrab = false;
 
-    m_connections << new QXcbConnection(m_nativeInterface.data(), canGrab);
+    // Parse arguments
+    const char *displayName = 0;
+    if (argc) {
+        int j = 1;
+        for (int i = 1; i < argc; i++) {
+            char *arg = argv[i];
+            if (arg) {
+                if (!strcmp(arg, "-display") && i < argc - 1) {
+                    displayName = argv[++i];
+                    arg = 0;
+                }
+            }
+            if (arg)
+                argv[j++] = arg;
+        }
+        argc = j;
+    } // argc
+
+    m_connections << new QXcbConnection(m_nativeInterface.data(), canGrab, displayName);
 
     for (int i = 0; i < parameters.size() - 1; i += 2) {
 #ifdef Q_XCB_DEBUG
diff --git a/src/plugins/platforms/xcb/qxcbintegration.h b/src/plugins/platforms/xcb/qxcbintegration.h
index 7042628203..cc39fb1462 100644
--- a/src/plugins/platforms/xcb/qxcbintegration.h
+++ b/src/plugins/platforms/xcb/qxcbintegration.h
@@ -55,7 +55,7 @@ class QXcbScreen;
 class QXcbIntegration : public QPlatformIntegration
 {
 public:
-    QXcbIntegration(const QStringList &parameters);
+    QXcbIntegration(const QStringList &parameters, int &argc, char **argv);
     ~QXcbIntegration();
 
     QPlatformWindow *createPlatformWindow(QWindow *window) const;