premiere-libtorrent/include/libtorrent/intrusive_ptr_base.hpp

/*

Copyright (c) 2007-2014, Arvid Norberg
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      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.

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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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*/

#ifndef TORRENT_INTRUSIVE_PTR_BASE
#define TORRENT_INTRUSIVE_PTR_BASE

#include <boost/detail/atomic_count.hpp>
#include <boost/checked_delete.hpp>
#include <boost/intrusive_ptr.hpp>
#include "libtorrent/config.hpp"
#include "libtorrent/assert.hpp"

namespace libtorrent
{
	template<class T>
	struct intrusive_ptr_base
	{
		intrusive_ptr_base(intrusive_ptr_base<T> const&)
			: m_refs(0) {}

		friend void intrusive_ptr_add_ref(intrusive_ptr_base<T> const* s)
		{
			TORRENT_ASSERT(s != 0);
			TORRENT_ASSERT(s->m_refs >= 0);
			++s->m_refs;
		}

		friend void intrusive_ptr_release(intrusive_ptr_base<T> const* s)
		{
			TORRENT_ASSERT(s != 0);
			TORRENT_ASSERT(s->m_refs > 0);
			if (--s->m_refs == 0)
				boost::checked_delete(static_cast<T const*>(s));
		}

		boost::intrusive_ptr<T> self()
		{ return boost::intrusive_ptr<T>((T*)this); }

		boost::intrusive_ptr<const T> self() const
		{ return boost::intrusive_ptr<const T>((T const*)this); }

		int refcount() const { return m_refs; }

		intrusive_ptr_base(): m_refs(0) {}

	private:

		// reference counter for intrusive_ptr
		mutable boost::detail::atomic_count m_refs;
	};

}

#endif