Initial Commit

include/asio/detail/recycling_allocator.hpp

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+//
+// detail/recycling_allocator.hpp
+// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2025 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_RECYCLING_ALLOCATOR_HPP
+#define ASIO_DETAIL_RECYCLING_ALLOCATOR_HPP
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1200)
+# pragma once
+#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
+
+#include "asio/detail/config.hpp"
+#include "asio/detail/memory.hpp"
+#include "asio/detail/thread_context.hpp"
+#include "asio/detail/thread_info_base.hpp"
+
+#include "asio/detail/push_options.hpp"
+
+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)
+  {
+#if !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
+    void* p = thread_info_base::allocate(Purpose(),
+        thread_context::top_of_thread_call_stack(),
+        sizeof(T) * n, alignof(T));
+#else // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
+    void* p = asio::aligned_new(alignof(T), sizeof(T) * n);
+#endif // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
+    return static_cast<T*>(p);
+  }
+
+  void deallocate(T* p, std::size_t n)
+  {
+#if !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
+    thread_info_base::deallocate(Purpose(),
+        thread_context::top_of_thread_call_stack(), p, sizeof(T) * n);
+#else // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
+    (void)n;
+    asio::aligned_delete(p);
+#endif // !defined(ASIO_DISABLE_SMALL_BLOCK_RECYCLING)
+  }
+};
+
+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
+
+#include "asio/detail/pop_options.hpp"
+
+#endif // ASIO_DETAIL_RECYCLING_ALLOCATOR_HPP