133 lines
2.8 KiB
Plaintext
133 lines
2.8 KiB
Plaintext
|
#ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_SPIN_HPP_INCLUDED
|
||
|
|
#define BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_SPIN_HPP_INCLUDED
|
||
|
|
|
||
|
|
// MS compatible compilers support #pragma once
|
||
|
|
|
||
|
|
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
|
||
|
|
# pragma once
|
||
|
|
#endif
|
||
|
|
|
||
|
|
//
|
||
|
|
// detail/sp_counted_base_spin.hpp - spinlock pool atomic emulation
|
||
|
|
//
|
||
|
|
// Copyright (c) 2001, 2002, 2003 Peter Dimov and Multi Media Ltd.
|
||
|
|
// Copyright 2004-2008 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)
|
||
|
|
//
|
||
|
|
|
||
|
|
#include <boost/detail/sp_typeinfo.hpp>
|
||
|
|
#include <boost/smart_ptr/detail/spinlock_pool.hpp>
|
||
|
|
|
||
|
|
namespace boost
|
||
|
|
{
|
||
|
|
|
||
|
|
namespace detail
|
||
|
|
{
|
||
|
|
|
||
|
|
inline int atomic_exchange_and_add( int * pw, int dv )
|
||
|
|
{
|
||
|
|
spinlock_pool<1>::scoped_lock lock( pw );
|
||
|
|
|
||
|
|
int r = *pw;
|
||
|
|
*pw += dv;
|
||
|
|
return r;
|
||
|
|
}
|
||
|
|
|
||
|
|
inline void atomic_increment( int * pw )
|
||
|
|
{
|
||
|
|
spinlock_pool<1>::scoped_lock lock( pw );
|
||
|
|
++*pw;
|
||
|
|
}
|
||
|
|
|
||
|
|
inline int atomic_conditional_increment( int * pw )
|
||
|
|
{
|
||
|
|
spinlock_pool<1>::scoped_lock lock( pw );
|
||
|
|
|
||
|
|
int rv = *pw;
|
||
|
|
if( rv != 0 ) ++*pw;
|
||
|
|
return rv;
|
||
|
|
}
|
||
|
|
|
||
|
|
class sp_counted_base
|
||
|
|
{
|
||
|
|
private:
|
||
|
|
|
||
|
|
sp_counted_base( sp_counted_base const & );
|
||
|
|
sp_counted_base & operator= ( sp_counted_base const & );
|
||
|
|
|
||
|
|
int use_count_; // #shared
|
||
|
|
int weak_count_; // #weak + (#shared != 0)
|
||
|
|
|
||
|
|
public:
|
||
|
|
|
||
|
|
sp_counted_base(): use_count_( 1 ), weak_count_( 1 )
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
virtual ~sp_counted_base() // nothrow
|
||
|
|
{
|
||
|
|
}
|
||
|
|
|
||
|
|
// dispose() is called when use_count_ drops to zero, to release
|
||
|
|
// the resources managed by *this.
|
||
|
|
|
||
|
|
virtual void dispose() = 0; // nothrow
|
||
|
|
|
||
|
|
// destroy() is called when weak_count_ drops to zero.
|
||
|
|
|
||
|
|
virtual void destroy() // nothrow
|
||
|
|
{
|
||
|
|
delete this;
|
||
|
|
}
|
||
|
|
|
||
|
|
virtual void * get_deleter( sp_typeinfo const & ti ) = 0;
|
||
|
|
virtual void * get_untyped_deleter() = 0;
|
||
|
|
|
||
|
|
void add_ref_copy()
|
||
|
|
{
|
||
|
|
atomic_increment( &use_count_ );
|
||
|
|
}
|
||
|
|
|
||
|
|
bool add_ref_lock() // true on success
|
||
|
|
{
|
||
|
|
return atomic_conditional_increment( &use_count_ ) != 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
void release() // nothrow
|
||
|
|
{
|
||
|
|
if( atomic_exchange_and_add( &use_count_, -1 ) == 1 )
|
||
|
|
{
|
||
|
|
dispose();
|
||
|
|
weak_release();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void weak_add_ref() // nothrow
|
||
|
|
{
|
||
|
|
atomic_increment( &weak_count_ );
|
||
|
|
}
|
||
|
|
|
||
|
|
void weak_release() // nothrow
|
||
|
|
{
|
||
|
|
if( atomic_exchange_and_add( &weak_count_, -1 ) == 1 )
|
||
|
|
{
|
||
|
|
destroy();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
long use_count() const // nothrow
|
||
|
|
{
|
||
|
|
spinlock_pool<1>::scoped_lock lock( &use_count_ );
|
||
|
|
return use_count_;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
} // namespace detail
|
||
|
|
|
||
|
|
} // namespace boost
|
||
|
|
|
||
|
|
#endif // #ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_SPIN_HPP_INCLUDED
|