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- //
- // detail/thread_info_base.hpp
- // ~~~~~~~~~~~~~~~~~~~~~~~~~~~
- //
- // Copyright (c) 2003-2015 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 ASIO_DETAIL_THREAD_INFO_BASE_HPP
- #define ASIO_DETAIL_THREAD_INFO_BASE_HPP
-
- #if defined(_MSC_VER) && (_MSC_VER >= 1200)
- # pragma once
- #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
-
- #include <climits>
- #include <cstddef>
- #include "asio/detail/noncopyable.hpp"
-
- #include "asio/detail/push_options.hpp"
-
- namespace asio {
- namespace detail {
-
- class thread_info_base
- : private noncopyable
- {
- public:
- thread_info_base()
- : reusable_memory_(0)
- {
- }
-
- ~thread_info_base()
- {
- if (reusable_memory_)
- ::operator delete(reusable_memory_);
- }
-
- static void* allocate(thread_info_base* this_thread, std::size_t size)
- {
- if (this_thread && this_thread->reusable_memory_)
- {
- void* const pointer = this_thread->reusable_memory_;
- this_thread->reusable_memory_ = 0;
-
- unsigned char* const mem = static_cast<unsigned char*>(pointer);
- if (static_cast<std::size_t>(mem[0]) >= size)
- {
- mem[size] = mem[0];
- return pointer;
- }
-
- ::operator delete(pointer);
- }
-
- void* const pointer = ::operator new(size + 1);
- unsigned char* const mem = static_cast<unsigned char*>(pointer);
- mem[size] = (size <= UCHAR_MAX) ? static_cast<unsigned char>(size) : 0;
- return pointer;
- }
-
- static void deallocate(thread_info_base* this_thread,
- void* pointer, std::size_t size)
- {
- if (size <= UCHAR_MAX)
- {
- if (this_thread && this_thread->reusable_memory_ == 0)
- {
- unsigned char* const mem = static_cast<unsigned char*>(pointer);
- mem[0] = mem[size];
- this_thread->reusable_memory_ = pointer;
- return;
- }
- }
-
- ::operator delete(pointer);
- }
-
- private:
- void* reusable_memory_;
- };
-
- } // namespace detail
- } // namespace asio
-
- #include "asio/detail/pop_options.hpp"
-
- #endif // ASIO_DETAIL_THREAD_INFO_BASE_HPP
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