shared_count.hpp

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#ifndef BOOST_SMART_PTR_DETAIL_SHARED_COUNT_HPP_INCLUDED
#define BOOST_SMART_PTR_DETAIL_SHARED_COUNT_HPP_INCLUDED
 
// MS compatible compilers support #pragma once
 
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif
 
//
//  detail/shared_count.hpp
//
//  Copyright (c) 2001, 2002, 2003 Peter Dimov and Multi Media Ltd.
//  Copyright 2004-2005 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)
//
 
#ifdef __BORLANDC__
# pragma warn -8027     // Functions containing try are not expanded inline
#endif
 
#include <boost/config.hpp>
#include <boost/checked_delete.hpp>
#include <boost/throw_exception.hpp>
#include <boost/smart_ptr/bad_weak_ptr.hpp>
#include <boost/smart_ptr/detail/sp_counted_base.hpp>
#include <boost/smart_ptr/detail/sp_counted_impl.hpp>
#include <boost/smart_ptr/detail/sp_disable_deprecated.hpp>
#include <boost/detail/workaround.hpp>
// 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 <functional>       // std::less
 
#ifdef BOOST_NO_EXCEPTIONS
# include <new>              // std::bad_alloc
#endif
 
#include <boost/core/addressof.hpp>
 
#if defined( BOOST_SP_DISABLE_DEPRECATED )
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
#endif
 
namespace boost
{
 
namespace movelib
{
 
    template< class T, class D > class unique_ptr;
 
} // namespace movelib
 
namespace detail
{
 
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
 
int const shared_count_id = 0x2C35F101;
int const   weak_count_id = 0x298C38A4;
 
#endif
 
struct sp_nothrow_tag {};
 
template< class D > struct sp_inplace_tag
{
};
 
template< class T > class sp_reference_wrapper
{ 
public:
 
    explicit sp_reference_wrapper( T & t): t_( boost::addressof( t ) )
    {
    }
 
    template< class Y > void operator()( Y * p ) const
    {
        (*t_)( p );
    }
 
private:
 
    T * t_;
};
 
template< class D > struct sp_convert_reference
{
    typedef D type;
};
 
template< class D > struct sp_convert_reference< D& >
{
    typedef sp_reference_wrapper< D > type;
};
 
class weak_count;
 
class shared_count
{
private:
 
    sp_counted_base * pi_;
 
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
    int id_;
#endif
 
    friend class weak_count;
 
public:
 
    shared_count(): pi_(0) // nothrow
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
    }
 
    template<class Y> explicit shared_count( Y * p ): pi_( 0 )
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
#ifndef BOOST_NO_EXCEPTIONS
 
        try
        {
            pi_ = new sp_counted_impl_p<Y>( p );
        }
        catch(...)
        {
            boost::checked_delete( p );
            throw;
        }
 
#else
 
        pi_ = new sp_counted_impl_p<Y>( p );
 
        if( pi_ == 0 )
        {
            boost::checked_delete( p );
            boost::throw_exception( std::bad_alloc() );
        }
 
#endif
    }
 
#if defined( BOOST_MSVC ) && BOOST_WORKAROUND( BOOST_MSVC, <= 1200 )
    template<class Y, class D> shared_count( Y * p, D d ): pi_(0)
#else
    template<class P, class D> shared_count( P p, D d ): pi_(0)
#endif
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
#if defined( BOOST_MSVC ) && BOOST_WORKAROUND( BOOST_MSVC, <= 1200 )
        typedef Y* P;
#endif
#ifndef BOOST_NO_EXCEPTIONS
 
        try
        {
            pi_ = new sp_counted_impl_pd<P, D>(p, d);
        }
        catch(...)
        {
            d(p); // delete p
            throw;
        }
 
#else
 
        pi_ = new sp_counted_impl_pd<P, D>(p, d);
 
        if(pi_ == 0)
        {
            d(p); // delete p
            boost::throw_exception(std::bad_alloc());
        }
 
#endif
    }
 
#if !defined( BOOST_NO_FUNCTION_TEMPLATE_ORDERING )
 
    template< class P, class D > shared_count( P p, sp_inplace_tag<D> ): pi_( 0 )
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
#ifndef BOOST_NO_EXCEPTIONS
 
        try
        {
            pi_ = new sp_counted_impl_pd< P, D >( p );
        }
        catch( ... )
        {
            D::operator_fn( p ); // delete p
            throw;
        }
 
#else
 
        pi_ = new sp_counted_impl_pd< P, D >( p );
 
        if( pi_ == 0 )
        {
            D::operator_fn( p ); // delete p
            boost::throw_exception( std::bad_alloc() );
        }
 
#endif // #ifndef BOOST_NO_EXCEPTIONS
    }
 
#endif // !defined( BOOST_NO_FUNCTION_TEMPLATE_ORDERING )
 
    template<class P, class D, class A> shared_count( P p, D d, A a ): pi_( 0 )
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
        typedef sp_counted_impl_pda<P, D, A> impl_type;
 
#if !defined( BOOST_NO_CXX11_ALLOCATOR )
 
        typedef typename std::allocator_traits<A>::template rebind_alloc< impl_type > A2;
 
#else
 
        typedef typename A::template rebind< impl_type >::other A2;
 
#endif
 
        A2 a2( a );
 
#ifndef BOOST_NO_EXCEPTIONS
 
        try
        {
#if !defined( BOOST_NO_CXX11_ALLOCATOR )
 
            impl_type * pi = std::allocator_traits<A2>::allocate( a2, 1 );
            pi_ = pi;
            std::allocator_traits<A2>::construct( a2, pi, p, d, a );
 
#else
 
            pi_ = a2.allocate( 1, static_cast< impl_type* >( 0 ) );
            ::new( static_cast< void* >( pi_ ) ) impl_type( p, d, a );
 
#endif
        }
        catch(...)
        {
            d( p );
 
            if( pi_ != 0 )
            {
                a2.deallocate( static_cast< impl_type* >( pi_ ), 1 );
            }
 
            throw;
        }
 
#else
 
#if !defined( BOOST_NO_CXX11_ALLOCATOR )
 
        impl_type * pi = std::allocator_traits<A2>::allocate( a2, 1 );
        pi_ = pi;
 
#else
 
        pi_ = a2.allocate( 1, static_cast< impl_type* >( 0 ) );
 
#endif
 
        if( pi_ != 0 )
        {
#if !defined( BOOST_NO_CXX11_ALLOCATOR )
 
            std::allocator_traits<A2>::construct( a2, pi, p, d, a );
 
#else
 
            ::new( static_cast< void* >( pi_ ) ) impl_type( p, d, a );
 
#endif
        }
        else
        {
            d( p );
            boost::throw_exception( std::bad_alloc() );
        }
 
#endif
    }
 
#if !defined( BOOST_NO_FUNCTION_TEMPLATE_ORDERING )
 
    template< class P, class D, class A > shared_count( P p, sp_inplace_tag< D >, A a ): pi_( 0 )
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
        typedef sp_counted_impl_pda< P, D, A > impl_type;
 
#if !defined( BOOST_NO_CXX11_ALLOCATOR )
 
        typedef typename std::allocator_traits<A>::template rebind_alloc< impl_type > A2;
 
#else
 
        typedef typename A::template rebind< impl_type >::other A2;
 
#endif
 
        A2 a2( a );
 
#ifndef BOOST_NO_EXCEPTIONS
 
        try
        {
#if !defined( BOOST_NO_CXX11_ALLOCATOR )
 
            impl_type * pi = std::allocator_traits<A2>::allocate( a2, 1 );
            pi_ = pi;
            std::allocator_traits<A2>::construct( a2, pi, p, a );
 
#else
 
            pi_ = a2.allocate( 1, static_cast< impl_type* >( 0 ) );
            ::new( static_cast< void* >( pi_ ) ) impl_type( p, a );
 
#endif
        }
        catch(...)
        {
            D::operator_fn( p );
 
            if( pi_ != 0 )
            {
                a2.deallocate( static_cast< impl_type* >( pi_ ), 1 );
            }
 
            throw;
        }
 
#else
 
#if !defined( BOOST_NO_CXX11_ALLOCATOR )
 
        impl_type * pi = std::allocator_traits<A2>::allocate( a2, 1 );
        pi_ = pi;
 
#else
 
        pi_ = a2.allocate( 1, static_cast< impl_type* >( 0 ) );
 
#endif
 
        if( pi_ != 0 )
        {
#if !defined( BOOST_NO_CXX11_ALLOCATOR )
 
            std::allocator_traits<A2>::construct( a2, pi, p, a );
 
#else
 
            ::new( static_cast< void* >( pi_ ) ) impl_type( p, a );
 
#endif
        }
        else
        {
            D::operator_fn( p );
            boost::throw_exception( std::bad_alloc() );
        }
 
#endif // #ifndef BOOST_NO_EXCEPTIONS
    }
 
#endif // !defined( BOOST_NO_FUNCTION_TEMPLATE_ORDERING )
 
#ifndef BOOST_NO_AUTO_PTR
 
    // auto_ptr<Y> is special cased to provide the strong guarantee
 
    template<class Y>
    explicit shared_count( std::auto_ptr<Y> & r ): pi_( new sp_counted_impl_p<Y>( r.get() ) )
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
#ifdef BOOST_NO_EXCEPTIONS
 
        if( pi_ == 0 )
        {
            boost::throw_exception(std::bad_alloc());
        }
 
#endif
 
        r.release();
    }
 
#endif 
 
#if !defined( BOOST_NO_CXX11_SMART_PTR )
 
    template<class Y, class D>
    explicit shared_count( std::unique_ptr<Y, D> & r ): pi_( 0 )
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
        typedef typename sp_convert_reference<D>::type D2;
 
        D2 d2( r.get_deleter() );
        pi_ = new sp_counted_impl_pd< typename std::unique_ptr<Y, D>::pointer, D2 >( r.get(), d2 );
 
#ifdef BOOST_NO_EXCEPTIONS
 
        if( pi_ == 0 )
        {
            boost::throw_exception( std::bad_alloc() );
        }
 
#endif
 
        r.release();
    }
 
#endif
 
    template<class Y, class D>
    explicit shared_count( boost::movelib::unique_ptr<Y, D> & r ): pi_( 0 )
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
        typedef typename sp_convert_reference<D>::type D2;
 
        D2 d2( r.get_deleter() );
        pi_ = new sp_counted_impl_pd< typename boost::movelib::unique_ptr<Y, D>::pointer, D2 >( r.get(), d2 );
 
#ifdef BOOST_NO_EXCEPTIONS
 
        if( pi_ == 0 )
        {
            boost::throw_exception( std::bad_alloc() );
        }
 
#endif
 
        r.release();
    }
 
    ~shared_count() // nothrow
    {
        if( pi_ != 0 ) pi_->release();
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        id_ = 0;
#endif
    }
 
    shared_count(shared_count const & r): pi_(r.pi_) // nothrow
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
        if( pi_ != 0 ) pi_->add_ref_copy();
    }
 
#if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
 
    shared_count(shared_count && r): pi_(r.pi_) // nothrow
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
    {
        r.pi_ = 0;
    }
 
#endif
 
    explicit shared_count(weak_count const & r); // throws bad_weak_ptr when r.use_count() == 0
    shared_count( weak_count const & r, sp_nothrow_tag ); // constructs an empty *this when r.use_count() == 0
 
    shared_count & operator= (shared_count const & r) // nothrow
    {
        sp_counted_base * tmp = r.pi_;
 
        if( tmp != pi_ )
        {
            if( tmp != 0 ) tmp->add_ref_copy();
            if( pi_ != 0 ) pi_->release();
            pi_ = tmp;
        }
 
        return *this;
    }
 
    void swap(shared_count & r) // nothrow
    {
        sp_counted_base * tmp = r.pi_;
        r.pi_ = pi_;
        pi_ = tmp;
    }
 
    long use_count() const // nothrow
    {
        return pi_ != 0? pi_->use_count(): 0;
    }
 
    bool unique() const // nothrow
    {
        return use_count() == 1;
    }
 
    bool empty() const // nothrow
    {
        return pi_ == 0;
    }
 
    friend inline bool operator==(shared_count const & a, shared_count const & b)
    {
        return a.pi_ == b.pi_;
    }
 
    friend inline bool operator<(shared_count const & a, shared_count const & b)
    {
        return std::less<sp_counted_base *>()( a.pi_, b.pi_ );
    }
 
    void * get_deleter( sp_typeinfo const & ti ) const
    {
        return pi_? pi_->get_deleter( ti ): 0;
    }
 
    void * get_untyped_deleter() const
    {
        return pi_? pi_->get_untyped_deleter(): 0;
    }
};
 
 
class weak_count
{
private:
 
    sp_counted_base * pi_;
 
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
    int id_;
#endif
 
    friend class shared_count;
 
public:
 
    weak_count(): pi_(0) // nothrow
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(weak_count_id)
#endif
    {
    }
 
    weak_count(shared_count const & r): pi_(r.pi_) // nothrow
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(weak_count_id)
#endif
    {
        if(pi_ != 0) pi_->weak_add_ref();
    }
 
    weak_count(weak_count const & r): pi_(r.pi_) // nothrow
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(weak_count_id)
#endif
    {
        if(pi_ != 0) pi_->weak_add_ref();
    }
 
// Move support
 
#if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
 
    weak_count(weak_count && r): pi_(r.pi_) // nothrow
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(weak_count_id)
#endif
    {
        r.pi_ = 0;
    }
 
#endif
 
    ~weak_count() // nothrow
    {
        if(pi_ != 0) pi_->weak_release();
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        id_ = 0;
#endif
    }
 
    weak_count & operator= (shared_count const & r) // nothrow
    {
        sp_counted_base * tmp = r.pi_;
 
        if( tmp != pi_ )
        {
            if(tmp != 0) tmp->weak_add_ref();
            if(pi_ != 0) pi_->weak_release();
            pi_ = tmp;
        }
 
        return *this;
    }
 
    weak_count & operator= (weak_count const & r) // nothrow
    {
        sp_counted_base * tmp = r.pi_;
 
        if( tmp != pi_ )
        {
            if(tmp != 0) tmp->weak_add_ref();
            if(pi_ != 0) pi_->weak_release();
            pi_ = tmp;
        }
 
        return *this;
    }
 
    void swap(weak_count & r) // nothrow
    {
        sp_counted_base * tmp = r.pi_;
        r.pi_ = pi_;
        pi_ = tmp;
    }
 
    long use_count() const // nothrow
    {
        return pi_ != 0? pi_->use_count(): 0;
    }
 
    bool empty() const // nothrow
    {
        return pi_ == 0;
    }
 
    friend inline bool operator==(weak_count const & a, weak_count const & b)
    {
        return a.pi_ == b.pi_;
    }
 
    friend inline bool operator<(weak_count const & a, weak_count const & b)
    {
        return std::less<sp_counted_base *>()(a.pi_, b.pi_);
    }
};
 
inline shared_count::shared_count( weak_count const & r ): pi_( r.pi_ )
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
{
    if( pi_ == 0 || !pi_->add_ref_lock() )
    {
        boost::throw_exception( boost::bad_weak_ptr() );
    }
}
 
inline shared_count::shared_count( weak_count const & r, sp_nothrow_tag ): pi_( r.pi_ )
#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS)
        , id_(shared_count_id)
#endif
{
    if( pi_ != 0 && !pi_->add_ref_lock() )
    {
        pi_ = 0;
    }
}
 
} // namespace detail
 
} // namespace boost
 
#if defined( BOOST_SP_DISABLE_DEPRECATED )
#pragma GCC diagnostic pop
#endif
 
#ifdef __BORLANDC__
# pragma warn .8027     // Functions containing try are not expanded inline
#endif
 
#endif  // #ifndef BOOST_SMART_PTR_DETAIL_SHARED_COUNT_HPP_INCLUDED