Implement generating of private cpp exports

Add the generating of private cpp exports for Qt modules.

Add the GENERATE_PRIVATE_CPP_EXPORTS option to qt_internal_add_module
that is the manual switch for private exports generator. Existing
modules in qtbase doesn't follow any strict convention of using
private cpp export. So there is no clue how to detect if generating of
the private exports is required or not for the module.

Use autogenerated private cpp exports in QtNetwork module.

CPP_EXPORT_HEADER_NAME argument of the qt_internal_add_module function
is replaced by the CPP_EXPORT_HEADER_BASE_NAME and has a different
meaning. The provided name is used as a base name for the private and
non-private headers that contains cpp exports. Header files suffixes
are constant: .h and _p.h for the non-private and private header files
accordingly.

Pick-to: 6.2
Task-number: QTBUG-90492
Change-Id: Icf11304e00379fb8521a865965c19b974e01e62f
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

1 files changed, 58 insertions, 0 deletions

diff --git a/cmake/modulecppexports_p.h.in b/cmake/modulecppexports_p.h.in
new file mode 100644
index 0000000000..5912bbba70
--- /dev/null
+++ b/cmake/modulecppexports_p.h.in
@@ -0,0 +1,58 @@
+/****************************************************************************
+**
+** 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 @header_base_name_upper@_P_H
+#define @header_base_name_upper@_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 <@module_include_name@/@header_base_name@.h>
+
+#define Q_@module_define_infix@_PRIVATE_EXPORT Q_@module_define_infix@_EXPORT
+
+#endif // @header_base_name_upper@_P_H