#ifndef BOOST_SMART_PTR_SHARED_PTR_HPP_INCLUDED

#define BOOST_SMART_PTR_SHARED_PTR_HPP_INCLUDED

//

//  shared_ptr.hpp

//

//  (C) Copyright Greg Colvin and Beman Dawes 1998, 1999.

//  Copyright (c) 2001-2008 Peter Dimov

//

//  Distributed under the Boost Software License, Version 1.0. (See

//  accompanying file LICENSE_1_0.txt or copy at

//  http://www.boost.org/LICENSE_1_0.txt)

//

//  See http://www.boost.org/libs/smart_ptr/shared_ptr.htm for documentation.

//

#include <boost/config.hpp>   // for broken compiler workarounds

#if defined(BOOST_NO_MEMBER_TEMPLATES) && !defined(BOOST_MSVC6_MEMBER_TEMPLATES)

#include <boost/smart_ptr/detail/shared_ptr_nmt.hpp>

#else

// In order to avoid circular dependencies with Boost.TR1

// we make sure that our include of <memory> doesn't try to

// pull in the TR1 headers: that's why we use this header 

// rather than including <memory> directly:

#include <boost/config/no_tr1/memory.hpp>  // std::auto_ptr

#include <boost/assert.hpp>

#include <boost/checked_delete.hpp>

#include <boost/throw_exception.hpp>

#include <boost/smart_ptr/detail/shared_count.hpp>

#include <boost/detail/workaround.hpp>

#include <boost/smart_ptr/detail/sp_convertible.hpp>

#if !defined(BOOST_SP_NO_ATOMIC_ACCESS)

#include <boost/smart_ptr/detail/spinlock_pool.hpp>

#include <boost/memory_order.hpp>

#endif

#include <algorithm>            // for std::swap

#include <functional>           // for std::less

#include <typeinfo>             // for std::bad_cast

#if !defined(BOOST_NO_IOSTREAM)

#if !defined(BOOST_NO_IOSFWD)

#include <iosfwd>               // for std::basic_ostream

#else

#include <ostream>

#endif

#endif

#ifdef BOOST_MSVC  // moved here to work around VC++ compiler crash

# pragma warning(push)

# pragma warning(disable:4284) // odd return type for operator->

#endif

namespace boost

{

template<class T> class shared_ptr;

template<class T> class weak_ptr;

template<class T> class enable_shared_from_this;

namespace detail

{

struct static_cast_tag {};

struct const_cast_tag {};

struct dynamic_cast_tag {};

struct polymorphic_cast_tag {};

template<class T> struct shared_ptr_traits

{

    typedef T & reference;

};

template<> struct shared_ptr_traits<void>

{

    typedef void reference;

};

#if !defined(BOOST_NO_CV_VOID_SPECIALIZATIONS)

template<> struct shared_ptr_traits<void const>

{

    typedef void reference;

};

template<> struct shared_ptr_traits<void volatile>

{

    typedef void reference;

};

template<> struct shared_ptr_traits<void const volatile>

{

    typedef void reference;

};

#endif

// enable_shared_from_this support

template< class X, class Y, class T > inline void sp_enable_shared_from_this( boost::shared_ptr<X> const * ppx, Y const * py, boost::enable_shared_from_this< T > const * pe )

{

    if( pe != 0 )

    {

        pe->_internal_accept_owner( ppx, const_cast< Y* >( py ) );

    }

}

#ifdef _MANAGED

// Avoid C4793, ... causes native code generation

struct sp_any_pointer

{

    template<class T> sp_any_pointer( T* ) {}

};

inline void sp_enable_shared_from_this( sp_any_pointer, sp_any_pointer, sp_any_pointer )

{

}

#else // _MANAGED

inline void sp_enable_shared_from_this( ... )

{

}

#endif // _MANAGED

#if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION ) && !defined( BOOST_NO_AUTO_PTR )

// rvalue auto_ptr support based on a technique by Dave Abrahams

template< class T, class R > struct sp_enable_if_auto_ptr

{

};

template< class T, class R > struct sp_enable_if_auto_ptr< std::auto_ptr< T >, R >

{

    typedef R type;

}; 

#endif

} // namespace detail

//

//  shared_ptr

//

//  An enhanced relative of scoped_ptr with reference counted copy semantics.

//  The object pointed to is deleted when the last shared_ptr pointing to it

//  is destroyed or reset.

//

template<class T> class shared_ptr

{

private:

    // Borland 5.5.1 specific workaround

    typedef shared_ptr<T> this_type;

public:

    typedef T element_type;

    typedef T value_type;

    typedef T * pointer;

    typedef typename boost::detail::shared_ptr_traits<T>::reference reference;

    shared_ptr(): px(0), pn() // never throws in 1.30+

    {

    }

    template<class Y>

    explicit shared_ptr( Y * p ): px( p ), pn( p ) // Y must be complete

    {

        boost::detail::sp_enable_shared_from_this( this, p, p );

    }

    //

    // Requirements: D's copy constructor must not throw

    //

    // shared_ptr will release p by calling d(p)

    //

    template<class Y, class D> shared_ptr(Y * p, D d): px(p), pn(p, d)

    {

        boost::detail::sp_enable_shared_from_this( this, p, p );

    }

    // As above, but with allocator. A's copy constructor shall not throw.

    template<class Y, class D, class A> shared_ptr( Y * p, D d, A a ): px( p ), pn( p, d, a )

    {

        boost::detail::sp_enable_shared_from_this( this, p, p );

    }

//  generated copy constructor, destructor are fine

    template<class Y>

    explicit shared_ptr(weak_ptr<Y> const & r): pn(r.pn) // may throw

    {

        // it is now safe to copy r.px, as pn(r.pn) did not throw

        px = r.px;

    }

    template<class Y>

    shared_ptr( weak_ptr<Y> const & r, boost::detail::sp_nothrow_tag ): px( 0 ), pn( r.pn, boost::detail::sp_nothrow_tag() ) // never throws

    {

        if( !pn.empty() )

        {

            px = r.px;

        }

    }

    template<class Y>

#if !defined( BOOST_SP_NO_SP_CONVERTIBLE )

    shared_ptr( shared_ptr<Y> const & r, typename detail::sp_enable_if_convertible<Y,T>::type = detail::sp_empty() )

#else

    shared_ptr( shared_ptr<Y> const & r )

#endif

    : px( r.px ), pn( r.pn ) // never throws

    {

    }

    // aliasing

    template< class Y >

    shared_ptr( shared_ptr<Y> const & r, T * p ): px( p ), pn( r.pn ) // never throws

    {

    }

    template<class Y>

    shared_ptr(shared_ptr<Y> const & r, boost::detail::static_cast_tag): px(static_cast<element_type *>(r.px)), pn(r.pn)

    {

    }

    template<class Y>

    shared_ptr(shared_ptr<Y> const & r, boost::detail::const_cast_tag): px(const_cast<element_type *>(r.px)), pn(r.pn)

    {

    }

    template<class Y>

    shared_ptr(shared_ptr<Y> const & r, boost::detail::dynamic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(r.pn)

    {

        if(px == 0) // need to allocate new counter -- the cast failed

        {

            pn = boost::detail::shared_count();

        }

    }

    template<class Y>

    shared_ptr(shared_ptr<Y> const & r, boost::detail::polymorphic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(r.pn)

    {

        if(px == 0)

        {

            boost::throw_exception(std::bad_cast());

        }

    }

#ifndef BOOST_NO_AUTO_PTR

    template<class Y>

    explicit shared_ptr(std::auto_ptr<Y> & r): px(r.get()), pn()

    {

        Y * tmp = r.get();

        pn = boost::detail::shared_count(r);

        boost::detail::sp_enable_shared_from_this( this, tmp, tmp );

    }

#if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )

    template<class Ap>

    explicit shared_ptr( Ap r, typename boost::detail::sp_enable_if_auto_ptr<Ap, int>::type = 0 ): px( r.get() ), pn()

    {

        typename Ap::element_type * tmp = r.get();

        pn = boost::detail::shared_count( r );

        boost::detail::sp_enable_shared_from_this( this, tmp, tmp );

    }

#endif // BOOST_NO_SFINAE, BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION

#endif // BOOST_NO_AUTO_PTR

    // assignment

    shared_ptr & operator=( shared_ptr const & r ) // never throws

    {

        this_type(r).swap(*this);

        return *this;

    }

#if !defined(BOOST_MSVC) || (BOOST_MSVC >= 1400)

    template<class Y>

    shared_ptr & operator=(shared_ptr<Y> const & r) // never throws

    {

        this_type(r).swap(*this);

        return *this;

    }

#endif

#ifndef BOOST_NO_AUTO_PTR

    template<class Y>

    shared_ptr & operator=( std::auto_ptr<Y> & r )

    {

        this_type(r).swap(*this);

        return *this;

    }

#if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )

    template<class Ap>

    typename boost::detail::sp_enable_if_auto_ptr< Ap, shared_ptr & >::type operator=( Ap r )

    {

        this_type( r ).swap( *this );

        return *this;

    }

#endif // BOOST_NO_SFINAE, BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION

#endif // BOOST_NO_AUTO_PTR

// Move support

#if defined( BOOST_HAS_RVALUE_REFS )

    shared_ptr( shared_ptr && r ): px( r.px ), pn() // never throws

    {

        pn.swap( r.pn );

        r.px = 0;

    }

    template<class Y>

#if !defined( BOOST_SP_NO_SP_CONVERTIBLE )

    shared_ptr( shared_ptr<Y> && r, typename detail::sp_enable_if_convertible<Y,T>::type = detail::sp_empty() )

#else

    shared_ptr( shared_ptr<Y> && r )

#endif

    : px( r.px ), pn() // never throws

    {

        pn.swap( r.pn );

        r.px = 0;

    }

    shared_ptr & operator=( shared_ptr && r ) // never throws

    {

        this_type( static_cast< shared_ptr && >( r ) ).swap( *this );

        return *this;

    }

    template<class Y>

    shared_ptr & operator=( shared_ptr<Y> && r ) // never throws

    {

        this_type( static_cast< shared_ptr<Y> && >( r ) ).swap( *this );

        return *this;

    }

#endif

    void reset() // never throws in 1.30+

    {

        this_type().swap(*this);

    }

    template<class Y> void reset(Y * p) // Y must be complete

    {

        BOOST_ASSERT(p == 0 || p != px); // catch self-reset errors

        this_type(p).swap(*this);

    }

    template<class Y, class D> void reset( Y * p, D d )

    {

        this_type( p, d ).swap( *this );

    }

    template<class Y, class D, class A> void reset( Y * p, D d, A a )

    {

        this_type( p, d, a ).swap( *this );

    }

    template<class Y> void reset( shared_ptr<Y> const & r, T * p )

    {

        this_type( r, p ).swap( *this );

    }

    reference operator* () const // never throws

    {

        BOOST_ASSERT(px != 0);

        return *px;

    }

    T * operator-> () const // never throws

    {

        BOOST_ASSERT(px != 0);

        return px;

    }

    T * get() const // never throws

    {

        return px;

    }

// implicit conversion to "bool"

#include <boost/smart_ptr/detail/operator_bool.hpp>

    bool unique() const // never throws

    {

        return pn.unique();

    }

    long use_count() const // never throws

    {

        return pn.use_count();

    }

    void swap(shared_ptr<T> & other) // never throws

    {

        std::swap(px, other.px);

        pn.swap(other.pn);

    }

    template<class Y> bool _internal_less(shared_ptr<Y> const & rhs) const

    {

        return pn < rhs.pn;

    }

    void * _internal_get_deleter( detail::sp_typeinfo const & ti ) const

    {

        return pn.get_deleter( ti );

    }

    bool _internal_equiv( shared_ptr const & r ) const

    {

        return px == r.px && pn == r.pn;

    }

// Tasteless as this may seem, making all members public allows member templates

// to work in the absence of member template friends. (Matthew Langston)

#ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS

private:

    template<class Y> friend class shared_ptr;

    template<class Y> friend class weak_ptr;

#endif

    T * px;                     // contained pointer

    boost::detail::shared_count pn;    // reference counter

};  // shared_ptr

template<class T, class U> inline bool operator==(shared_ptr<T> const & a, shared_ptr<U> const & b)

{

    return a.get() == b.get();

}

template<class T, class U> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<U> const & b)

{

    return a.get() != b.get();

}

#if __GNUC__ == 2 && __GNUC_MINOR__ <= 96

// Resolve the ambiguity between our op!= and the one in rel_ops

template<class T> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<T> const & b)

{

    return a.get() != b.get();

}

#endif

template<class T, class U> inline bool operator<(shared_ptr<T> const & a, shared_ptr<U> const & b)

{

    return a._internal_less(b);

}

template<class T> inline void swap(shared_ptr<T> & a, shared_ptr<T> & b)

{

    a.swap(b);

}

template<class T, class U> shared_ptr<T> static_pointer_cast(shared_ptr<U> const & r)

{

    return shared_ptr<T>(r, boost::detail::static_cast_tag());

}

template<class T, class U> shared_ptr<T> const_pointer_cast(shared_ptr<U> const & r)

{

    return shared_ptr<T>(r, boost::detail::const_cast_tag());

}

template<class T, class U> shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const & r)

{

    return shared_ptr<T>(r, boost::detail::dynamic_cast_tag());

}

// shared_*_cast names are deprecated. Use *_pointer_cast instead.

template<class T, class U> shared_ptr<T> shared_static_cast(shared_ptr<U> const & r)

{

    return shared_ptr<T>(r, boost::detail::static_cast_tag());

}

template<class T, class U> shared_ptr<T> shared_dynamic_cast(shared_ptr<U> const & r)

{

    return shared_ptr<T>(r, boost::detail::dynamic_cast_tag());

}

template<class T, class U> shared_ptr<T> shared_polymorphic_cast(shared_ptr<U> const & r)

{