Turn Scripting into a proper singleton

There is only one instance hold by Workspace which means it should follow
the common approach with ::self and ::create.

REVIEW: 109850

scripting/scripting.cpp

@@ -574,6 +574,15 @@ void KWin::DeclarativeScript::run()
     setRunning(true);
 }
 
+KWin::Scripting *KWin::Scripting::s_self = NULL;
+
+KWin::Scripting *KWin::Scripting::create(QObject *parent)
+{
+    Q_ASSERT(!s_self);
+    s_self = new Scripting(parent);
+    return s_self;
+}
+
 KWin::Scripting::Scripting(QObject *parent)
     : QObject(parent)
     , m_scriptsLock(new QMutex(QMutex::Recursive))
@@ -735,6 +744,7 @@ KWin::Scripting::~Scripting()
 {
     QDBusConnection::sessionBus().unregisterObject("/Scripting");
     QDBusConnection::sessionBus().unregisterService("org.kde.kwin.Scripting");
+    s_self = NULL;
 }
 
 QList< QAction * > KWin::Scripting::actionsForUserActionMenu(KWin::Client *c, QMenu *parent)

scripting/scripting.h

@@ -287,6 +287,7 @@ class Scripting : public QObject
     Q_OBJECT
     Q_CLASSINFO("D-Bus Interface", "org.kde.kwin.Scripting")
 private:
+    explicit Scripting(QObject *parent);
     QStringList scriptList;
     QList<KWin::AbstractScript*> scripts;
     /**
@@ -298,7 +299,6 @@ private:
     void runScripts();
 
 public:
-    explicit Scripting(QObject *parent = NULL);
     ~Scripting();
     Q_SCRIPTABLE Q_INVOKABLE int loadScript(const QString &filePath, const QString &pluginName = QString());
     Q_SCRIPTABLE Q_INVOKABLE int loadDeclarativeScript(const QString &filePath, const QString &pluginName = QString());
@@ -314,6 +314,9 @@ public:
      **/
     QList<QAction*> actionsForUserActionMenu(Client *c, QMenu *parent);
 
+    static Scripting *self();
+    static Scripting *create(QObject *parent);
+
 public Q_SLOTS:
     void scriptDestroyed(QObject *object);
     Q_SCRIPTABLE void start();
@@ -323,7 +326,14 @@ private Q_SLOTS:
 
 private:
     LoadScriptList queryScriptsToLoad();
+    static Scripting *s_self;
 };
 
+inline
+Scripting *Scripting::self()
+{
+    return s_self;
+}
+
 }
 #endif

useractions.cpp

@@ -453,7 +453,7 @@ void UserActionsMenu::menuAboutToShow()
     m_scriptsMenu = NULL;
     // ask scripts whether they want to add entries for the given Client
     m_scriptsMenu = new QMenu(m_menu);
-    QList<QAction*> scriptActions = ws->scripting()->actionsForUserActionMenu(m_client.data(), m_scriptsMenu);
+    QList<QAction*> scriptActions = Scripting::self()->actionsForUserActionMenu(m_client.data(), m_scriptsMenu);
     if (!scriptActions.isEmpty()) {
         m_scriptsMenu->setFont(KGlobalSettings::menuFont());
         m_scriptsMenu->addActions(scriptActions);

workspace.cpp

@@ -136,7 +136,6 @@ Workspace::Workspace(bool restore)
     , set_active_client_recursion(0)
     , block_stacking_updates(0)
     , forced_global_mouse_grab(false)
-    , m_scripting(NULL)
 {
     // If KWin was already running it saved its configuration after loosing the selection -> Reread
     QFuture<void> reparseConfigFuture = QtConcurrent::run(options, &Options::reparseConfiguration);
@@ -492,7 +491,7 @@ void Workspace::init()
 
 
 #ifdef KWIN_BUILD_SCRIPTING
-    m_scripting = new Scripting(this);
+    Scripting::create(this);
 #endif
 
     // SELI TODO: This won't work with unreasonable focus policies,

workspace.h

@@ -69,7 +69,6 @@ class Outline;
 class RootInfo;
 class PluginMgr;
 class Rules;
-class Scripting;
 class UserActionsMenu;
 class WindowRules;
 class Compositor;
@@ -243,12 +242,6 @@ public:
         return client_keys;
     }
 
-#ifdef KWIN_BUILD_SCRIPTING
-    Scripting *scripting() {
-        return m_scripting;
-    }
-#endif
-
     /**
      * Returns the list of clients sorted in stacking order, with topmost client
      * at the last position
@@ -652,8 +645,6 @@ private:
     bool forced_global_mouse_grab;
     friend class StackingUpdatesBlocker;
 
-    Scripting *m_scripting;
-
     QScopedPointer<KillWindow> m_windowKiller;
 
 private: