Files
statechart/example/BitMachine/UniqueObjectAllocator.hpp
Andreas Huber 2944fac997 Various small changes and bug fixes
[SVN r18613]
2003-05-30 15:12:19 +00:00

65 lines
1.8 KiB
C++

#ifndef UNIQUE_OBJECT_ALLOCATOR_HPP_INCLUDED
#define UNIQUE_OBJECT_ALLOCATOR_HPP_INCLUDED
//////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2002-2003 Andreas Huber Doenni, Switzerland
// Permission to copy, use, modify, sell and distribute this software
// is granted provided this copyright notice appears in all copies.
// This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.
//////////////////////////////////////////////////////////////////////////////
#include <boost/type_traits/alignment_of.hpp>
#include <boost/type_traits/type_with_alignment.hpp>
#include <cstddef> // size_t
//////////////////////////////////////////////////////////////////////////////
template< class T >
class UniqueObjectAllocator
{
public:
//////////////////////////////////////////////////////////////////////////
static void * allocate( size_t size )
{
size;
BOOST_ASSERT( !constructed_ && ( size == sizeof( T ) ) );
constructed_ = true;
return &storage_.data[ 0 ];
}
static void deallocate( void * p, size_t size )
{
p;
size;
BOOST_ASSERT( constructed_ &&
( p == &storage_.data[ 0 ] ) && ( size == sizeof( T ) ) );
constructed_ = false;
}
private:
//////////////////////////////////////////////////////////////////////////
union storage
{
char data[ sizeof( T ) ];
typename boost::type_with_alignment<
boost::alignment_of< T >::value >::type aligner_;
};
static bool constructed_;
static storage storage_;
};
template< class T >
bool UniqueObjectAllocator< T >::constructed_ = false;
template< class T >
typename UniqueObjectAllocator< T >::storage
UniqueObjectAllocator< T >::storage_;
#endif