Do not include qloggingcategory.h in public headers

Reduce overhead for including qguiapplication.h by splitting
up qnativeinterface.h into a public and a private part.

[ChangeLog][Potentially Source-Incompatible Changes] The
qguiapplication.h header no longer implicitly includes
qloggingcategory.h. If your code depends on the transitive
include, explicitly include <QLoggingCategory> where needed.

Pick-to: 6.2
Task-number: QTBUG-97601
Change-Id: Ic02327a1c3092e21730160af5c59a9d58dc1239c
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

3 files changed, 102 insertions, 35 deletions

diff --git a/src/corelib/global/qglobal.cpp b/src/corelib/global/qglobal.cpp
index d455f887ed..c8f97c7148 100644
--- a/src/corelib/global/qglobal.cpp
+++ b/src/corelib/global/qglobal.cpp
@@ -52,6 +52,7 @@
 #endif // Q_OS_WIN || Q_OS_CYGWIN
 #include <private/qlocale_tools_p.h>
 #include "qnativeinterface.h"
+#include "qnativeinterface_p.h"
 
 #include <qmutex.h>
 #include <QtCore/private/qlocking_p.h>
@@ -4923,8 +4924,8 @@ bool QInternal::activateCallbacks(Callback cb, void **parameters)
     declares __CFMutableString and CFMutableStringRef.
 */
 
-namespace QNativeInterface::Private {
-    Q_LOGGING_CATEGORY(lcNativeInterface, "qt.nativeinterface")
+namespace QtPrivate {
+Q_LOGGING_CATEGORY(lcNativeInterface, "qt.nativeinterface")
 }
 
 QT_END_NAMESPACE
diff --git a/src/corelib/global/qnativeinterface.h b/src/corelib/global/qnativeinterface.h
index 56805d5a6e..bc25600efc 100644
--- a/src/corelib/global/qnativeinterface.h
+++ b/src/corelib/global/qnativeinterface.h
@@ -41,7 +41,6 @@
 #define QNATIVEINTERFACE_H
 
 #include <QtCore/qglobal.h>
-#include <QtCore/qloggingcategory.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -159,9 +158,6 @@ namespace QNativeInterface::Private {
     // of incompatible interface types read better.
     template <typename I>
     struct NativeInterface : TypeInfo<I> {};
-
-    Q_CORE_EXPORT Q_DECLARE_LOGGING_CATEGORY(lcNativeInterface)
-
 } // QNativeInterface::Private
 
 // Declares an accessor for the native interface
@@ -183,35 +179,6 @@ namespace QNativeInterface::Private {
     public:
 #endif
 
-// Provides a definition for the interface destructor
-#define QT_DEFINE_NATIVE_INTERFACE_2(Namespace, InterfaceClass) \
-    QT_PREPEND_NAMESPACE(Namespace)::InterfaceClass::~InterfaceClass() = default
-
-#define QT_DEFINE_NATIVE_INTERFACE(...) QT_OVERLOADED_MACRO(QT_DEFINE_NATIVE_INTERFACE, QNativeInterface, __VA_ARGS__)
-#define QT_DEFINE_PRIVATE_NATIVE_INTERFACE(...) QT_OVERLOADED_MACRO(QT_DEFINE_NATIVE_INTERFACE, QNativeInterface::Private, __VA_ARGS__)
-
-#define QT_NATIVE_INTERFACE_RETURN_IF(NativeInterface, baseType) \
-    { \
-        using QNativeInterface::Private::lcNativeInterface; \
-        using QNativeInterface::Private::TypeInfo; \
-        qCDebug(lcNativeInterface, "Comparing requested interface name %s with available %s", \
-                name, TypeInfo<NativeInterface>::name()); \
-        if (qstrcmp(name, TypeInfo<NativeInterface>::name()) == 0) { \
-            qCDebug(lcNativeInterface, "Match for interface %s. Comparing revisions (requested %d / available %d)", \
-                name, revision, TypeInfo<NativeInterface>::revision()); \
-            if (revision == TypeInfo<NativeInterface>::revision()) { \
-                qCDebug(lcNativeInterface) << "Full match. Returning dynamic cast of" << baseType; \
-                return dynamic_cast<NativeInterface*>(baseType); \
-            } else { \
-                qCWarning(lcNativeInterface, "Native interface revision mismatch (requested %d / available %d) for interface %s", \
-                    revision, TypeInfo<NativeInterface>::revision(), name); \
-                return nullptr; \
-            } \
-        } else { \
-            qCDebug(lcNativeInterface, "No match for requested interface name %s", name); \
-        } \
-    }
-
 QT_END_NAMESPACE
 
 #endif // QNATIVEINTERFACE_H
diff --git a/src/corelib/global/qnativeinterface_p.h b/src/corelib/global/qnativeinterface_p.h
new file mode 100644
index 0000000000..65332eeecb
--- /dev/null
+++ b/src/corelib/global/qnativeinterface_p.h
@@ -0,0 +1,99 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 QNATIVEINTERFACE_P_H
+#define QNATIVEINTERFACE_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/qglobal.h>
+#include <QtCore/qloggingcategory.h>
+
+QT_BEGIN_NAMESPACE
+
+namespace QtPrivate {
+Q_CORE_EXPORT Q_DECLARE_LOGGING_CATEGORY(lcNativeInterface)
+}
+
+// Provides a definition for the interface destructor
+#define QT_DEFINE_NATIVE_INTERFACE_2(Namespace, InterfaceClass)                                    \
+    QT_PREPEND_NAMESPACE(Namespace)::InterfaceClass::~InterfaceClass() = default
+
+#define QT_DEFINE_NATIVE_INTERFACE(...)                                                            \
+    QT_OVERLOADED_MACRO(QT_DEFINE_NATIVE_INTERFACE, QNativeInterface, __VA_ARGS__)
+#define QT_DEFINE_PRIVATE_NATIVE_INTERFACE(...)                                                    \
+    QT_OVERLOADED_MACRO(QT_DEFINE_NATIVE_INTERFACE, QNativeInterface::Private, __VA_ARGS__)
+
+#define QT_NATIVE_INTERFACE_RETURN_IF(NativeInterface, baseType)                                   \
+    {                                                                                              \
+        using QtPrivate::lcNativeInterface;                                                        \
+        using QNativeInterface::Private::TypeInfo;                                                 \
+        qCDebug(lcNativeInterface, "Comparing requested interface name %s with available %s",      \
+                name, TypeInfo<NativeInterface>::name());                                          \
+        if (qstrcmp(name, TypeInfo<NativeInterface>::name()) == 0) {                               \
+            qCDebug(lcNativeInterface,                                                             \
+                    "Match for interface %s. Comparing revisions (requested %d / available %d)",   \
+                    name, revision, TypeInfo<NativeInterface>::revision());                        \
+            if (revision == TypeInfo<NativeInterface>::revision()) {                               \
+                qCDebug(lcNativeInterface) << "Full match. Returning dynamic cast of" << baseType; \
+                return dynamic_cast<NativeInterface *>(baseType);                                  \
+            } else {                                                                               \
+                qCWarning(lcNativeInterface,                                                       \
+                          "Native interface revision mismatch (requested %d / available %d) for "  \
+                          "interface %s",                                                          \
+                          revision, TypeInfo<NativeInterface>::revision(), name);                  \
+                return nullptr;                                                                    \
+            }                                                                                      \
+        } else {                                                                                   \
+            qCDebug(lcNativeInterface, "No match for requested interface name %s", name);          \
+        }                                                                                          \
+    }
+
+QT_END_NAMESPACE
+
+#endif // QNATIVEINTERFACE_P_H