1 // 2 // handler_alloc_hook.hpp 3 // ~~~~~~~~~~~~~~~~~~~~~~ 4 // 5 // Copyright (c) 2003-2015 Christopher M. Kohlhoff (chris at kohlhoff dot com) 6 // 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) 9 // 10 11 #ifndef BOOST_ASIO_HANDLER_ALLOC_HOOK_HPP 12 #define BOOST_ASIO_HANDLER_ALLOC_HOOK_HPP 13 14 #if defined(_MSC_VER) && (_MSC_VER >= 1200) 15 # pragma once 16 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) 17 18 #include <boost/asio/detail/config.hpp> 19 #include <cstddef> 20 21 #include <boost/asio/detail/push_options.hpp> 22 23 namespace boost { 24 namespace asio { 25 26 /// Default allocation function for handlers. 27 /** 28 * Asynchronous operations may need to allocate temporary objects. Since 29 * asynchronous operations have a handler function object, these temporary 30 * objects can be said to be associated with the handler. 31 * 32 * Implement asio_handler_allocate and asio_handler_deallocate for your own 33 * handlers to provide custom allocation for these temporary objects. 34 * 35 * The default implementation of these allocation hooks uses <tt>::operator 36 * new</tt> and <tt>::operator delete</tt>. 37 * 38 * @note All temporary objects associated with a handler will be deallocated 39 * before the upcall to the handler is performed. This allows the same memory to 40 * be reused for a subsequent asynchronous operation initiated by the handler. 41 * 42 * @par Example 43 * @code 44 * class my_handler; 45 * 46 * void* asio_handler_allocate(std::size_t size, my_handler* context) 47 * { 48 * return ::operator new(size); 49 * } 50 * 51 * void asio_handler_deallocate(void* pointer, std::size_t size, 52 * my_handler* context) 53 * { 54 * ::operator delete(pointer); 55 * } 56 * @endcode 57 */ 58 BOOST_ASIO_DECL void* asio_handler_allocate( 59 std::size_t size, ...); 60 61 /// Default deallocation function for handlers. 62 /** 63 * Implement asio_handler_allocate and asio_handler_deallocate for your own 64 * handlers to provide custom allocation for the associated temporary objects. 65 * 66 * The default implementation of these allocation hooks uses <tt>::operator 67 * new</tt> and <tt>::operator delete</tt>. 68 * 69 * @sa asio_handler_allocate. 70 */ 71 BOOST_ASIO_DECL void asio_handler_deallocate( 72 void* pointer, std::size_t size, ...); 73 74 } // namespace asio 75 } // namespace boost 76 77 #include <boost/asio/detail/pop_options.hpp> 78 79 #if defined(BOOST_ASIO_HEADER_ONLY) 80 # include <boost/asio/impl/handler_alloc_hook.ipp> 81 #endif // defined(BOOST_ASIO_HEADER_ONLY) 82 83 #endif // BOOST_ASIO_HANDLER_ALLOC_HOOK_HPP 84