2 // detail/object_pool.hpp
3 // ~~~~~~~~~~~~~~~~~~~~~~
5 // Copyright (c) 2003-2016 Christopher M. Kohlhoff (chris at kohlhoff dot com)
7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
11 #ifndef BOOST_ASIO_DETAIL_OBJECT_POOL_HPP
12 #define BOOST_ASIO_DETAIL_OBJECT_POOL_HPP
14 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
16 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
18 #include <boost/asio/detail/noncopyable.hpp>
20 #include <boost/asio/detail/push_options.hpp>
26 template <typename Object>
29 class object_pool_access
32 template <typename Object>
33 static Object* create()
38 template <typename Object>
39 static void destroy(Object* o)
44 template <typename Object>
45 static Object*& next(Object* o)
50 template <typename Object>
51 static Object*& prev(Object* o)
57 template <typename Object>
69 // Destructor destroys all objects.
72 destroy_list(live_list_);
73 destroy_list(free_list_);
76 // Get the object at the start of the live list.
82 // Allocate a new object.
85 Object* o = free_list_;
87 free_list_ = object_pool_access::next(free_list_);
89 o = object_pool_access::create<Object>();
91 object_pool_access::next(o) = live_list_;
92 object_pool_access::prev(o) = 0;
94 object_pool_access::prev(live_list_) = o;
100 // Free an object. Moves it to the free list. No destructors are run.
104 live_list_ = object_pool_access::next(o);
106 if (object_pool_access::prev(o))
108 object_pool_access::next(object_pool_access::prev(o))
109 = object_pool_access::next(o);
112 if (object_pool_access::next(o))
114 object_pool_access::prev(object_pool_access::next(o))
115 = object_pool_access::prev(o);
118 object_pool_access::next(o) = free_list_;
119 object_pool_access::prev(o) = 0;
124 // Helper function to destroy all elements in a list.
125 void destroy_list(Object* list)
130 list = object_pool_access::next(o);
131 object_pool_access::destroy(o);
135 // The list of live objects.
142 } // namespace detail
146 #include <boost/asio/detail/pop_options.hpp>
148 #endif // BOOST_ASIO_DETAIL_OBJECT_POOL_HPP