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#include "qmlcleanup_p.h"
#include <private/qmlengine_p.h>

/*!
\internal
\class QmlCleanup
\brief The QmlCleanup provides a callback when a QmlEngine is deleted. 

Any object that needs cleanup to occur before the QmlEngine's QScriptEngine is
destroyed should inherit from QmlCleanup.  The clear() virtual method will be
called by QmlEngine just before it deletes the QScriptEngine.
*/

/*!
\internal

Create a QmlCleanup for \a engine
*/
QmlCleanup::QmlCleanup(QmlEngine *engine)
: prev(0), next(0)
{
    Q_ASSERT(engine);
    QmlEnginePrivate *p = QmlEnginePrivate::get(engine);

    if (p->cleanup) next = p->cleanup;
    p->cleanup = this;
    prev = &p->cleanup;
    if (next) next->prev = &next;
}

/*!
\internal
*/
QmlCleanup::~QmlCleanup()
{
    if (prev) *prev = next;
    if (next) next->prev = prev;
    prev = 0; 
    next = 0;
}