QMetaType: Now we can register typedefs.

Task-number: QTBUG-6833
Task-number: QTBUG-937
Reviewed-by: Brad
Reviewed-by: Kent Hansen

2 files changed, 93 insertions, 4 deletions

diff --git a/src/corelib/kernel/qmetatype.cpp b/src/corelib/kernel/qmetatype.cpp
index 779b69b..be506b4 100644
--- a/src/corelib/kernel/qmetatype.cpp
+++ b/src/corelib/kernel/qmetatype.cpp
@@ -352,6 +352,7 @@ public:
     QMetaType::SaveOperator saveOp;
     QMetaType::LoadOperator loadOp;
 #endif
+    int alias;
 };
 
 Q_DECLARE_TYPEINFO(QCustomTypeInfo, Q_MOVABLE_TYPE);
@@ -436,8 +437,11 @@ static int qMetaTypeCustomType_unlocked(const char *typeName, int length)
         return 0;
 
     for (int v = 0; v < ct->count(); ++v) {
-        if ((length == ct->at(v).typeName.size())
-            && !strcmp(typeName, ct->at(v).typeName.constData())) {
+        const QCustomTypeInfo &customInfo = ct->at(v);
+        if ((length == customInfo.typeName.size())
+            && !strcmp(typeName, customInfo.typeName.constData())) {
+            if (customInfo.alias >= 0)
+                return customInfo.alias;
             return v + QMetaType::User;
         }
     }
@@ -475,6 +479,7 @@ int QMetaType::registerType(const char *typeName, Destructor destructor,
             inf.typeName = normalizedTypeName;
             inf.constr = constructor;
             inf.destr = destructor;
+            inf.alias = -1;
             idx = ct->size() + User;
             ct->append(inf);
         }
@@ -482,6 +487,51 @@ int QMetaType::registerType(const char *typeName, Destructor destructor,
     return idx;
 }
 
+/*! \internal
+    \since 4.7
+
+    Registers a user type for marshalling, as an alias of another type (typedef)
+*/
+int QMetaType::registerTypedef(const char* typeName, int aliasId)
+{
+    QVector<QCustomTypeInfo> *ct = customTypes();
+    if (!ct || !typeName)
+        return -1;
+
+#ifdef QT_NO_QOBJECT
+    NS(QByteArray) normalizedTypeName = typeName;
+#else
+    NS(QByteArray) normalizedTypeName = QMetaObject::normalizedType(typeName);
+#endif
+
+    int idx = qMetaTypeStaticType(normalizedTypeName.constData(),
+                                  normalizedTypeName.size());
+
+    if (idx) {
+        Q_ASSERT(idx == aliasId);
+        return idx;
+    }
+
+    QWriteLocker locker(customTypesLock());
+    idx = qMetaTypeCustomType_unlocked(normalizedTypeName.constData(),
+                                           normalizedTypeName.size());
+
+    if (idx) {
+        Q_ASSERT(idx == aliasId);
+        return idx;
+    }
+
+    if (!idx) {
+        QCustomTypeInfo inf;
+        inf.typeName = normalizedTypeName;
+        inf.alias = aliasId;
+        inf.constr = 0;
+        inf.destr = 0;
+        ct->append(inf);
+    }
+    return aliasId;
+}
+
 /*!
     \since 4.4
 
@@ -507,6 +557,7 @@ void QMetaType::unregisterType(const char *typeName)
             inf.typeName.clear();
             inf.constr = 0;
             inf.destr = 0;
+            inf.alias = -1;
         }
     }
 }
@@ -1349,6 +1400,11 @@ void QMetaType::destroy(int type, void *data)
 
     \snippet doc/src/snippets/code/src_corelib_kernel_qmetatype.cpp 4
 
+    This function is usefull to register typedefs so they can be used
+    by QMetaProperty, or in QueuedConnections
+
+    \snippet doc/src/snippets/code/src_corelib_kernel_qmetatype.cpp 9
+
     \sa qRegisterMetaTypeStreamOperators(), QMetaType::isRegistered(),
         Q_DECLARE_METATYPE()
 */
diff --git a/src/corelib/kernel/qmetatype.h b/src/corelib/kernel/qmetatype.h
index 33126e8..2ed4a1f 100644
--- a/src/corelib/kernel/qmetatype.h
+++ b/src/corelib/kernel/qmetatype.h
@@ -113,6 +113,7 @@ public:
 #endif
     static int registerType(const char *typeName, Destructor destructor,
                             Constructor constructor);
+    static int registerTypedef(const char *typeName, int aliasId);
     static int type(const char *typeName);
     static const char *typeName(int type);
     static bool isRegistered(int type);
@@ -154,13 +155,31 @@ void qMetaTypeLoadHelper(QDataStream &stream, T *t)
 }
 #endif // QT_NO_DATASTREAM
 
+template <typename T> struct QMetaTypeId2;
+
+namespace QtPrivate {
+    template <typename T, bool Defined = QMetaTypeId2<T>::Defined>
+    struct QMetaTypeIdHelper {
+        static inline int qt_metatype_id()
+        { return QMetaTypeId2<T>::qt_metatype_id(); }
+    };
+    template <typename T> struct QMetaTypeIdHelper<T, false> {
+        static inline int qt_metatype_id()
+        { return -1; }
+    };
+}
+
 template <typename T>
 int qRegisterMetaType(const char *typeName
 #ifndef qdoc
-    , T * /* dummy */ = 0
+    , typename QMetaTypeId2<T>::CustomType * dummy = 0
 #endif
 )
 {
+    const int typedefOf = dummy ? -1 : QtPrivate::QMetaTypeIdHelper<T>::qt_metatype_id();
+    if (typedefOf != -1)
+        return QMetaType::registerTypedef(typeName, typedefOf);
+
     typedef void*(*ConstructPtr)(const T*);
     ConstructPtr cptr = qMetaTypeConstructHelper<T>;
     typedef void(*DeletePtr)(T*);
@@ -170,6 +189,17 @@ int qRegisterMetaType(const char *typeName
                                    reinterpret_cast<QMetaType::Constructor>(cptr));
 }
 
+template <typename T>
+int qRegisterMetaType(const char *typeName
+#ifndef qdoc
+    , typename QMetaTypeId2<T>::BuiltinType * /* dummy */ = 0
+#endif
+)
+{
+    return QMetaType::registerTypedef(typeName, QMetaTypeId2<T>::MetaType);
+}
+
+
 #ifndef QT_NO_DATASTREAM
 template <typename T>
 void qRegisterMetaTypeStreamOperators(const char *typeName
@@ -198,6 +228,7 @@ struct QMetaTypeId
 template <typename T>
 struct QMetaTypeId2
 {
+    typedef T CustomType;
     enum { Defined = QMetaTypeId<T>::Defined };
     static inline int qt_metatype_id() { return QMetaTypeId<T>::qt_metatype_id(); }
 };
@@ -254,7 +285,8 @@ inline int qRegisterMetaTypeStreamOperators()
             {                                                           \
                 static QBasicAtomicInt metatype_id = Q_BASIC_ATOMIC_INITIALIZER(0); \
                 if (!metatype_id)                                       \
-                    metatype_id = qRegisterMetaType< TYPE >(#TYPE);     \
+                    metatype_id = qRegisterMetaType< TYPE >(#TYPE,      \
+                               reinterpret_cast< TYPE *>(quintptr(-1))); \
                 return metatype_id;                                     \
             }                                                           \
     };                                                                  \
@@ -264,6 +296,7 @@ inline int qRegisterMetaTypeStreamOperators()
     QT_BEGIN_NAMESPACE \
     template<> struct QMetaTypeId2<TYPE> \
     { \
+        typedef TYPE BuiltinType; \
         enum { Defined = 1, MetaType = QMetaType::NAME }; \
         static inline int qt_metatype_id() { return QMetaType::NAME; } \
     }; \