/*
* Copyright (C) 2013 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
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* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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#ifndef ResourceOwner_h
#define ResourceOwner_h
#include "core/fetch/ResourcePtr.h"
namespace WebCore {
template<class R, class C = typename R::ClientType>
class ResourceOwner : public C {
public:
typedef R ResourceType;
virtual ~ResourceOwner();
ResourceType* resource() const { return m_resource.get(); }
protected:
ResourceOwner();
ResourceOwner(const ResourceOwner& other) { setResource(other.resource()); }
explicit ResourceOwner(const ResourcePtr<ResourceType>&);
void setResource(const ResourcePtr<ResourceType>&);
void clearResource();
ResourceOwner& operator=(const ResourceOwner& other);
private:
ResourcePtr<ResourceType> m_resource;
};
template<class R, class C>
inline ResourceOwner<R, C>::ResourceOwner()
{
}
template<class R, class C>
inline ResourceOwner<R, C>::~ResourceOwner()
{
clearResource();
}
template<class R, class C>
inline ResourceOwner<R, C>::ResourceOwner(const ResourcePtr<R>& resource)
: m_resource(resource)
{
if (m_resource)
m_resource->addClient(this);
}
template<class R, class C>
inline void ResourceOwner<R, C>::setResource(const ResourcePtr<R>& newResource)
{
if (newResource == m_resource)
return;
// Some ResourceClient implementations reenter this so
// we need to prevent double removal.
if (ResourcePtr<ResourceType> oldResource = m_resource) {
m_resource.clear();
oldResource->removeClient(this);
}
if (newResource) {
m_resource = newResource;
m_resource->addClient(this);
}
}
template<class R, class C>
inline void ResourceOwner<R, C>::clearResource()
{
setResource(0);
}
template<class R, class C>
inline ResourceOwner<R, C>& ResourceOwner<R, C>::operator=(const ResourceOwner<R, C>& other)
{
if (this == &other)
return *this;
setResource(other.resource());
return *this;
}
} // namespace WebCore
#endif