shared_count.h
#ifndef BOOSTER_SMART_PTR_DETAIL_SHARED_COUNT_HPP_INCLUDED
#define BOOSTER_SMART_PTR_DETAIL_SHARED_COUNT_HPP_INCLUDED
//
// 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 <booster/config.h>
#include <booster/checked_delete.h>
#include <booster/bad_weak_ptr.h>
#include <booster/smart_ptr/sp_counted_base.h>
#include <booster/smart_ptr/sp_counted_impl.h>
#include <memory>
#include <functional> // std::less
#include <new> // std::bad_alloc
namespace booster
{
namespace detail
{
struct sp_nothrow_tag {};
class weak_count;
class shared_count
{
private:
sp_counted_base * pi_;
friend class weak_count;
public:
shared_count(): pi_(0) // nothrow
{
}
template<class Y> explicit shared_count( Y * p ): pi_( 0 )
{
try
{
pi_ = new sp_counted_impl_p<Y>( p );
}
catch(...)
{
booster::checked_delete( p );
throw;
}
}
template<class P, class D> shared_count( P p, D d ): pi_(0)
{
try
{
pi_ = new sp_counted_impl_pd<P, D>(p, d);
}
catch(...)
{
d(p); // delete p
throw;
}
}
template<class P, class D, class A> shared_count( P p, D d, A a ): pi_( 0 )
{
typedef sp_counted_impl_pda<P, D, A> impl_type;
typedef typename A::template rebind< impl_type >::other A2;
A2 a2( a );
try
{
pi_ = a2.allocate( 1, static_cast< impl_type* >( 0 ) );
new( static_cast< void* >( pi_ ) ) impl_type( p, d, a );
}
catch(...)
{
d( p );
if( pi_ != 0 )
{
a2.deallocate( static_cast< impl_type* >( pi_ ), 1 );
}
throw;
}
}
// 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() ) )
{
r.release();
}
~shared_count() // nothrow
{
if( pi_ != 0 ) pi_->release();
}
shared_count(shared_count const & r): pi_(r.pi_) // nothrow
{
if( pi_ != 0 ) pi_->add_ref_copy();
}
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;
}
};
class weak_count
{
private:
sp_counted_base * pi_;
friend class shared_count;
public:
weak_count(): pi_(0) // nothrow
{
}
weak_count(shared_count const & r): pi_(r.pi_) // nothrow
{
if(pi_ != 0) pi_->weak_add_ref();
}
weak_count(weak_count const & r): pi_(r.pi_) // nothrow
{
if(pi_ != 0) pi_->weak_add_ref();
}
~weak_count() // nothrow
{
if(pi_ != 0) pi_->weak_release();
}
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( pi_ == 0 || !pi_->add_ref_lock() )
{
throw booster::bad_weak_ptr();
}
}
inline shared_count::shared_count( weak_count const & r, sp_nothrow_tag ): pi_( r.pi_ )
{
if( pi_ != 0 && !pi_->add_ref_lock() )
{
pi_ = 0;
}
}
} // namespace detail
} // namespace boost
#ifdef __BORLANDC__
# pragma warn .8027 // Functions containing try are not expanded inline
#endif
#endif // #ifndef BOOST_SMART_PTR_DETAIL_SHARED_COUNT_HPP_INCLUDED
booster::detail::shared_count
Definition: shared_count.h:37
booster::detail::sp_counted_base
Definition: sp_counted_base.h:39
booster::detail::sp_counted_impl_pd
Definition: sp_counted_impl.h:77
booster::detail::weak_count
Definition: shared_count.h:179
booster::detail::sp_counted_impl_p
Definition: sp_counted_impl.h:32
booster::detail::sp_counted_impl_pda
Definition: sp_counted_impl.h:119
booster::detail::sp_nothrow_tag
Definition: shared_count.h:33
booster::bad_weak_ptr
Definition: bad_weak_ptr.h:36