Implemented type discovery feature.

The problem:

- There are two class, A and B, B inherits from A.
- You are inside a virtual method reimplemented in python with just one parameter of type A*.
- But the object referenced by a variable of type A* is an instance of B and it was created by C++,
  not Python!
- Shiboken needs to create a PyObject of type B, not A! This does not makes sense for C++, but does
  for Python, because python variables does not store type information, just values.

To achieve this we use RTTI to get the real type name of a variable, then we create the PyObject using
the TypeResolver infrastructure initially developed to help with signal slot problems. In other words,
the TypeResolver class has been moved from libpyside to libshiboken.

1 files changed, 113 insertions, 0 deletions

diff --git a/libshiboken/typeresolver.h b/libshiboken/typeresolver.h
new file mode 100644
index 000000000..4e7efb81b
--- /dev/null
+++ b/libshiboken/typeresolver.h
@@ -0,0 +1,113 @@
+/*
+ * This file is part of the Shiboken Python Bindings Generator project.
+ *
+ * Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+ *
+ * Contact: PySide team <contact@pyside.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * version 2.1 as published by the Free Software Foundation. Please
+ * review the following information to ensure the GNU Lesser General
+ * Public License version 2.1 requirements will be met:
+ * http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+ *
+ * As a special exception to the GNU Lesser General Public License
+ * version 2.1, the object code form of a "work that uses the Library"
+ * may incorporate material from a header file that is part of the
+ * Library.  You may distribute such object code under terms of your
+ * choice, provided that the incorporated material (i) does not exceed
+ * more than 5% of the total size of the Library; and (ii) is limited to
+ * numerical parameters, data structure layouts, accessors, macros,
+ * inline functions and templates.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#ifndef TYPERESOLVER_H
+#define TYPERESOLVER_H
+
+#include "shibokenmacros.h"
+#include "conversions.h"
+
+namespace Shiboken
+{
+
+class SbkBaseWrapperType;
+
+/* To C++ convertion functions. */
+template <typename T>
+inline void* pythonToValueType(PyObject* pyobj)
+{
+    return Shiboken::CppObjectCopier<T>::copy(Shiboken::Converter<T>::toCpp(pyobj));
+}
+
+template <typename T>
+inline void* pythonToObjectType(PyObject* pyobj)
+{
+    return Shiboken::Converter<T*>::toCpp(pyobj);
+}
+
+template <typename T>
+inline void objectDeleter(void* data)
+{
+    delete reinterpret_cast<T*>(data);
+}
+
+template <typename T>
+inline PyObject* objectTypeToPython(void* cptr)
+{
+    return Shiboken::Converter<T*>::toPython(*reinterpret_cast<T**>(cptr));
+}
+
+class LIBSHIBOKEN_API TypeResolver
+{
+public:
+    typedef PyObject* (*CppToPythonFunc)(void*);
+    typedef void* (*PythonToCppFunc)(PyObject*);
+    typedef void (*DeleteObjectFunc)(void*);
+    typedef PyTypeObject* (*GetPyTypeFunc)();
+
+    ~TypeResolver();
+
+    template<typename T>
+    static TypeResolver* createValueTypeResolver(const char* typeName)
+    {
+        return new TypeResolver(typeName, &Shiboken::Converter<T>::toPython, &pythonToValueType<T>, &SbkType<T>, &objectDeleter<T>);
+    }
+
+    template<typename T>
+    static TypeResolver* createObjectTypeResolver(const char* typeName)
+    {
+        return new TypeResolver(typeName, &objectTypeToPython<T>, &pythonToObjectType<T>, &SbkType<T>);
+    }
+
+    static TypeResolver* get(const char* typeName);
+
+    const char* typeName() const;
+    PyObject* toPython(void* cppObj);
+    void* toCpp(PyObject* pyObj);
+    void deleteObject(void* object);
+    PyTypeObject* pythonType();
+
+private:
+    struct TypeResolverPrivate;
+    TypeResolverPrivate* m_d;
+
+    // disable object copy
+    TypeResolver(const TypeResolver&);
+    TypeResolver& operator=(const TypeResolver&);
+
+    TypeResolver(const char* typeName, CppToPythonFunc cppToPy, PythonToCppFunc pyToCpp, GetPyTypeFunc getPyType, DeleteObjectFunc deleter = 0);
+};
+}
+
+#endif