By moving the base fields to a QObjectBase_, QObject can be a type which also has a 'base' field. This allows writing a generic QOBJECT() macro that will work with any QObject type, including QObject itself. The container_of() macro ensures that the object to cast has a QObjectBase_ base field, giving some type safety guarantees. QObject must have no members but QObjectBase_ base, or else QOBJECT() breaks. QObjectBase_ is not a typedef and uses a trailing underscore to make it obvious it is not for normal use and to avoid potential abuse. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <20180419150145.24795-3-marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
		
			
				
	
	
		
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/*
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 * QBool Module
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 *
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 * Copyright IBM, Corp. 2009
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 *
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 * Authors:
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 *  Anthony Liguori   <aliguori@us.ibm.com>
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 *
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 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
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 * See the COPYING.LIB file in the top-level directory.
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 *
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 */
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#ifndef QBOOL_H
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#define QBOOL_H
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#include "qapi/qmp/qobject.h"
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struct QBool {
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    struct QObjectBase_ base;
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    bool value;
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};
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QBool *qbool_from_bool(bool value);
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bool qbool_get_bool(const QBool *qb);
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bool qbool_is_equal(const QObject *x, const QObject *y);
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void qbool_destroy_obj(QObject *obj);
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#endif /* QBOOL_H */
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