ext-boost/boost/asio/detail/recycling_allocator.hpp
2019-08-24 15:39:04 +02:00

109 lines
2.4 KiB
C++

//
// detail/recycling_allocator.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2019 Christopher M. Kohlhoff (chris at kohlhoff dot com)
//
// 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)
//
#ifndef BOOST_ASIO_DETAIL_RECYCLING_ALLOCATOR_HPP
#define BOOST_ASIO_DETAIL_RECYCLING_ALLOCATOR_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include <boost/asio/detail/config.hpp>
#include <boost/asio/detail/memory.hpp>
#include <boost/asio/detail/thread_context.hpp>
#include <boost/asio/detail/thread_info_base.hpp>
#include <boost/asio/detail/push_options.hpp>
namespace boost {
namespace asio {
namespace detail {
template <typename T, typename Purpose = thread_info_base::default_tag>
class recycling_allocator
{
public:
typedef T value_type;
template <typename U>
struct rebind
{
typedef recycling_allocator<U, Purpose> other;
};
recycling_allocator()
{
}
template <typename U>
recycling_allocator(const recycling_allocator<U, Purpose>&)
{
}
T* allocate(std::size_t n)
{
typedef thread_context::thread_call_stack call_stack;
void* p = thread_info_base::allocate(Purpose(),
call_stack::top(), sizeof(T) * n);
return static_cast<T*>(p);
}
void deallocate(T* p, std::size_t n)
{
typedef thread_context::thread_call_stack call_stack;
thread_info_base::deallocate(Purpose(),
call_stack::top(), p, sizeof(T) * n);
}
};
template <typename Purpose>
class recycling_allocator<void, Purpose>
{
public:
typedef void value_type;
template <typename U>
struct rebind
{
typedef recycling_allocator<U, Purpose> other;
};
recycling_allocator()
{
}
template <typename U>
recycling_allocator(const recycling_allocator<U, Purpose>&)
{
}
};
template <typename Allocator, typename Purpose>
struct get_recycling_allocator
{
typedef Allocator type;
static type get(const Allocator& a) { return a; }
};
template <typename T, typename Purpose>
struct get_recycling_allocator<std::allocator<T>, Purpose>
{
typedef recycling_allocator<T, Purpose> type;
static type get(const std::allocator<T>&) { return type(); }
};
} // namespace detail
} // namespace asio
} // namespace boost
#include <boost/asio/detail/pop_options.hpp>
#endif // BOOST_ASIO_DETAIL_RECYCLING_ALLOCATOR_HPP