libpyside: Fix reinterpret_casts related to DynamicQMetaObject

Previously, DynamicQMetaObject instances were retrieved
by direct reinterpret_cast from the SBK user data.
This is not entirely correct since the DynamicQMetaObject
is merely the first member of the struct TypeUserData.

Fix this by moving the struct TypeUserData to a private header
and correcting the casts.

Task-number: PYSIDE-784
Change-Id: I69ea68bd474c4a38a5f5c5bc3db8bc3bb086e012
Reviewed-by: Christian Tismer <tismer@stackless.com>

4 files changed, 73 insertions, 14 deletions

diff --git a/sources/pyside2/libpyside/pyside.cpp b/sources/pyside2/libpyside/pyside.cpp
index 367a1adc2..fbfad4185 100644
--- a/sources/pyside2/libpyside/pyside.cpp
+++ b/sources/pyside2/libpyside/pyside.cpp
@@ -38,6 +38,7 @@
 ****************************************************************************/
 
 #include "pyside.h"
+#include "pyside_p.h"
 #include "signalmanager.h"
 #include "pysideclassinfo_p.h"
 #include "pysideproperty_p.h"
@@ -188,13 +189,6 @@ void destroyQCoreApplication()
     MakeSingletonQAppWrapper(NULL);
 }
 
-struct TypeUserData {
-    explicit TypeUserData(PyTypeObject* type,  const QMetaObject* metaobject, std::size_t size) :
-        mo(type, metaobject), cppObjSize(size) {}
-    DynamicQMetaObject mo;
-    std::size_t cppObjSize;
-};
-
 std::size_t getSizeOfQObject(SbkObjectType* type)
 {
     using namespace Shiboken::ObjectType;
@@ -231,15 +225,16 @@ void initQObjectSubType(SbkObjectType *type, PyObject *args, PyObject * /* kwds
 
     PyObject* bases = PyTuple_GET_ITEM(args, 1);
     int numBases = PyTuple_GET_SIZE(bases);
-    QMetaObject* baseMo = 0;
+    DynamicQMetaObject *baseMo = nullptr;
     SbkObjectType* qobjBase = 0;
 
     for (int i = 0; i < numBases; ++i) {
         PyTypeObject* base = reinterpret_cast<PyTypeObject*>(PyTuple_GET_ITEM(bases, i));
         if (PyType_IsSubtype(base, qObjType)) {
-            baseMo = reinterpret_cast<QMetaObject*>(Shiboken::ObjectType::getTypeUserData(reinterpret_cast<SbkObjectType*>(base)));
+            void *typeUserData = Shiboken::ObjectType::getTypeUserData(reinterpret_cast<SbkObjectType*>(base));
+            baseMo = &(reinterpret_cast<TypeUserData *>(typeUserData)->mo);
             qobjBase = reinterpret_cast<SbkObjectType*>(base);
-            reinterpret_cast<DynamicQMetaObject*>(baseMo)->update();
+            baseMo->update();
             break;
         }
     }
diff --git a/sources/pyside2/libpyside/pyside_p.h b/sources/pyside2/libpyside/pyside_p.h
new file mode 100644
index 000000000..e3039ed0b
--- /dev/null
+++ b/sources/pyside2/libpyside/pyside_p.h
@@ -0,0 +1,60 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt for Python.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef PYSIDE_P_H
+#define PYSIDE_P_H
+
+#include <dynamicqmetaobject.h>
+
+namespace PySide
+{
+
+// Struct associated with QObject's via Shiboken::Object::getTypeUserData()
+struct TypeUserData
+{
+    explicit TypeUserData(PyTypeObject* type,  const QMetaObject* metaobject, std::size_t size) :
+        mo(type, metaobject), cppObjSize(size) {}
+
+    DynamicQMetaObject mo;
+    std::size_t cppObjSize;
+};
+
+} //namespace PySide
+
+#endif // PYSIDE_P_H
diff --git a/sources/pyside2/libpyside/pysideclassinfo.cpp b/sources/pyside2/libpyside/pysideclassinfo.cpp
index 645c03011..64b882673 100644
--- a/sources/pyside2/libpyside/pysideclassinfo.cpp
+++ b/sources/pyside2/libpyside/pysideclassinfo.cpp
@@ -39,6 +39,7 @@
 
 #include <sbkpython.h>
 #include "pysideclassinfo.h"
+#include "pyside_p.h"
 #include "pysideclassinfo_p.h"
 #include "dynamicqmetaobject.h"
 
@@ -107,9 +108,9 @@ PyObject *classCall(PyObject *self, PyObject *args, PyObject * /* kw */)
     }
 
     if (Shiboken::ObjectType::checkType(reinterpret_cast<PyTypeObject*>(klass))) {
-        PySide::DynamicQMetaObject* mo = reinterpret_cast<PySide::DynamicQMetaObject*>(Shiboken::ObjectType::getTypeUserData(reinterpret_cast<SbkObjectType*>(klass)));
-        if (mo) {
-            mo->addInfo(PySide::ClassInfo::getMap(data));
+        if (void *userData = Shiboken::ObjectType::getTypeUserData(reinterpret_cast<SbkObjectType*>(klass))) {
+            PySide::DynamicQMetaObject &mo = reinterpret_cast<PySide::TypeUserData *>(userData)->mo;
+            mo.addInfo(PySide::ClassInfo::getMap(data));
             pData->m_alreadyWrapped = true;
             validClass = true;
         }
diff --git a/sources/pyside2/libpyside/signalmanager.cpp b/sources/pyside2/libpyside/signalmanager.cpp
index 4119c8171..19779be5b 100644
--- a/sources/pyside2/libpyside/signalmanager.cpp
+++ b/sources/pyside2/libpyside/signalmanager.cpp
@@ -43,6 +43,7 @@
 #include "pysideproperty.h"
 #include "pysideproperty_p.h"
 #include "pyside.h"
+#include "pyside_p.h"
 #include "dynamicqmetaobject.h"
 #include "pysidemetafunction_p.h"
 
@@ -643,7 +644,9 @@ const QMetaObject* SignalManager::retrieveMetaObject(PyObject *self)
         mo = reinterpret_cast<DynamicQMetaObject*>(PyCObject_AsVoidPtr(pyMo));
 #endif
     } else {
-        mo = reinterpret_cast<DynamicQMetaObject*>(Shiboken::Object::getTypeUserData(reinterpret_cast<SbkObject*>(self)));
+        void *userData = Shiboken::Object::getTypeUserData(reinterpret_cast<SbkObject*>(self));
+        Q_ASSERT(userData);
+        mo = &(reinterpret_cast<TypeUserData *>(userData)->mo);
     }
 
     mo->update();