CTK/Libs/PluginFramework/ctkServiceRegistrationPrivate.h

/*=============================================================================

  Library: CTK

  Copyright (c) 2010 German Cancer Research Center,
    Division of Medical and Biological Informatics

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

=============================================================================*/


#ifndef CTKSERVICEREGISTRATIONPRIVATE_H
#define CTKSERVICEREGISTRATIONPRIVATE_H

#include <QHash>
#include <QMutex>

#include "ctkServiceReference.h"

namespace ctk {

  class PluginPrivate;
  class ServiceRegistration;

  class ServiceRegistrationPrivate
  {

  protected:

    ServiceRegistration* const q_ptr;

    /**
     * Service or ServiceFactory object.
     */
    QObject* service;

  public:

    Q_DECLARE_PUBLIC(ServiceRegistration);


    /**
     * Plugin registering this service.
     */
    PluginPrivate* plugin;

    /**
     * Reference object to this service registration.
     */
    ServiceReference* reference;

    /**
     * Service properties.
     */
    ServiceProperties properties;

    /**
     * Plugins dependent on this service. Integer is used as
     * reference counter, counting number of unbalanced getService().
     */
    QHash<Plugin*,int> dependents;

    /**
     * Object instances that factory has produced.
     */
    QHash<Plugin*, QObject*> serviceInstances;

    /**
     * Is service available. I.e., if <code>true</code> then holders
     * of a ServiceReference for the service are allowed to get it.
     */
    volatile bool available;

    /**
     * Avoid recursive unregistrations. I.e., if <code>true</code> then
     * unregistration of this service has started but is not yet
     * finished.
     */
    volatile bool unregistering;

    /**
     * Lock object for synchronous event delivery.
     */
    QMutex eventLock;

    QMutex propsLock;

    ServiceRegistrationPrivate(ServiceRegistration* sr, PluginPrivate* plugin, QObject* service,
                               const ServiceProperties& props);

    virtual ~ServiceRegistrationPrivate();

    /**
     * Check if a plugin uses this service
     *
     * @param p Plugin to check
     * @return true if plugin uses this service
     */
    bool isUsedByPlugin(Plugin* p);

    virtual QObject* getService();

  };

}

#endif // CTKSERVICEREGISTRATIONPRIVATE_H