#ifndef BOOST_SHARED_PTR_HPP_INCLUDED

#define BOOST_SHARED_PTR_HPP_INCLUDED

//

//  shared_ptr.hpp

//

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

//  Copyright (c) 2001-2006 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/detail/shared_ptr_nmt.hpp>

#else

#include <memory>               // for std::auto_ptr

#include <boost/assert.hpp>

#include <boost/checked_delete.hpp>

#include <boost/throw_exception.hpp>

#include <boost/detail/shared_count.hpp>

#include <boost/detail/workaround.hpp>

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

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

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

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

#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 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 T, class Y> void sp_enable_shared_from_this( shared_count const & pn, boost::enable_shared_from_this<T> const * pe, Y const * px )

{

    if(pe != 0) pe->_internal_weak_this._internal_assign(const_cast<Y*>(px), pn);

}

#ifdef sgi

// Turn off: the last argument of the varargs function "sp_enable_shared_from_this" is unnamed

# pragma set woff 3506

#endif

inline void sp_enable_shared_from_this( shared_count const & /*pn*/, ... )

{

}

#ifdef sgi

# pragma reset woff 3506

#endif

#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( pn, 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( pn, 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( pn, p, p );

    }

//  generated copy constructor, assignment, destructor are fine...

//  except that Borland C++ has a bug, and g++ with -Wsynth warns

#if defined(__BORLANDC__) || defined(__GNUC__)

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

    {

        px = r.px;

        pn = r.pn; // shared_count::op= doesn't throw

        return *this;

    }

#endif

    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(shared_ptr<Y> const & r): px(r.px), 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( pn, 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( pn, tmp, tmp );

    }

#endif // BOOST_NO_SFINAE, BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION

#endif // BOOST_NO_AUTO_PTR

#if !defined(BOOST_MSVC) || (BOOST_MSVC >= 1300)

    template<class Y>

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

    {

        px = r.px;

        pn = r.pn; // shared_count::op= doesn't throw

        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

    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 );

    }

    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"

#if defined(__SUNPRO_CC) && BOOST_WORKAROUND(__SUNPRO_CC, <= 0x580)

    operator bool () const

    {

        return px != 0;

    }

#elif defined( _MANAGED )

    static void unspecified_bool( this_type*** )

    {

    }

    typedef void (*unspecified_bool_type)( this_type*** );

    operator unspecified_bool_type() const // never throws

    {

        return px == 0? 0: unspecified_bool;

    }

#elif \

    ( defined(__MWERKS__) && BOOST_WORKAROUND(__MWERKS__, < 0x3200) ) || \

    ( defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 304) )

    typedef T * (this_type::*unspecified_bool_type)() const;

    operator unspecified_bool_type() const // never throws

    {

        return px == 0? 0: &this_type::get;

    }

#else 

    typedef T * this_type::*unspecified_bool_type;

    operator unspecified_bool_type() const // never throws

    {

        return px == 0? 0: &this_type::px;

    }

#endif

    // operator! is redundant, but some compilers need it

    bool operator! () const // never throws

    {

        return px == 0;

    }

    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(std::type_info const & ti) const

    {

        return pn.get_deleter(ti);

    }

// 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)

{

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

}

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

{

    BOOST_ASSERT(dynamic_cast<T *>(r.get()) == r.get());

    return shared_static_cast<T>(r);

}

// get_pointer() enables boost::mem_fn to recognize shared_ptr

template<class T> inline T * get_pointer(shared_ptr<T> const & p)

{

    return p.get();

}

// operator<<

#if defined(__GNUC__) &&  (__GNUC__ < 3)

template<class Y> std::ostream & operator<< (std::ostream & os, shared_ptr<Y> const & p)

{

    os << p.get();

    return os;

}

#else

// in STLport's no-iostreams mode no iostream symbols can be used

#ifndef _STLP_NO_IOSTREAMS

# if defined(BOOST_MSVC) && BOOST_WORKAROUND(BOOST_MSVC, < 1300 && __SGI_STL_PORT)

// MSVC6 has problems finding std::basic_ostream through the using declaration in namespace _STL

using std::basic_ostream;

template<class E, class T, class Y> basic_ostream<E, T> & operator<< (basic_ostream<E, T> & os, shared_ptr<Y> const & p)

# else

template<class E, class T, class Y> std::basic_ostream<E, T> & operator<< (std::basic_ostream<E, T> & os, shared_ptr<Y> const & p)

# endif 

{

    os << p.get();

    return os;

}

#endif // _STLP_NO_IOSTREAMS

#endif // __GNUC__ < 3

// get_deleter (experimental)

#if ( defined(__GNUC__) && BOOST_WORKAROUND(__GNUC__, < 3) ) || \