Implement generating of a module cpp export header

Add an option that automatically generates an export header for a Qt
module. The header contains only Q_DECL_EXPORT/Q_DECL_IMPORT related
content, so it's not a full replacement of 'global' header files.

Task-number: QTBUG-90492
Change-Id: I250d1201b11d4096b7e78e61cbf4565945fe6517
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

1 files changed, 55 insertions, 0 deletions

diff --git a/cmake/modulecppexports.h.in b/cmake/modulecppexports.h.in
new file mode 100644
index 0000000000..fb5c0d918c
--- /dev/null
+++ b/cmake/modulecppexports.h.in
@@ -0,0 +1,55 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the @module@ 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 QT@module_define_infix@EXPORTS_H
+#define QT@module_define_infix@EXPORTS_H
+
+#include <QtCore/qglobal.h>
+
+#if defined(QT_SHARED) || !defined(QT_STATIC)
+#  if defined(QT_BUILD_@module_define_infix@_LIB)
+#    define Q_@module_define_infix@_EXPORT Q_DECL_EXPORT
+#  else
+#    define Q_@module_define_infix@_EXPORT Q_DECL_IMPORT
+#  endif
+#else
+#  define Q_@module_define_infix@_EXPORT
+#endif
+
+#endif // QT@module_define_infix@EXPORTS_H