1 // 2 // detail/reactive_socket_recvfrom_op.hpp 3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 4 // 5 // Copyright (c) 2003-2019 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_DETAIL_REACTIVE_SOCKET_RECVFROM_OP_HPP 12 #define BOOST_ASIO_DETAIL_REACTIVE_SOCKET_RECVFROM_OP_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 <boost/asio/detail/bind_handler.hpp> 20 #include <boost/asio/detail/buffer_sequence_adapter.hpp> 21 #include <boost/asio/detail/fenced_block.hpp> 22 #include <boost/asio/detail/memory.hpp> 23 #include <boost/asio/detail/reactor_op.hpp> 24 #include <boost/asio/detail/socket_ops.hpp> 25 26 #include <boost/asio/detail/push_options.hpp> 27 28 namespace boost { 29 namespace asio { 30 namespace detail { 31 32 template <typename MutableBufferSequence, typename Endpoint> 33 class reactive_socket_recvfrom_op_base : public reactor_op 34 { 35 public: reactive_socket_recvfrom_op_base(socket_type socket,int protocol_type,const MutableBufferSequence & buffers,Endpoint & endpoint,socket_base::message_flags flags,func_type complete_func)36 reactive_socket_recvfrom_op_base(socket_type socket, int protocol_type, 37 const MutableBufferSequence& buffers, Endpoint& endpoint, 38 socket_base::message_flags flags, func_type complete_func) 39 : reactor_op(&reactive_socket_recvfrom_op_base::do_perform, complete_func), 40 socket_(socket), 41 protocol_type_(protocol_type), 42 buffers_(buffers), 43 sender_endpoint_(endpoint), 44 flags_(flags) 45 { 46 } 47 do_perform(reactor_op * base)48 static status do_perform(reactor_op* base) 49 { 50 reactive_socket_recvfrom_op_base* o( 51 static_cast<reactive_socket_recvfrom_op_base*>(base)); 52 53 buffer_sequence_adapter<boost::asio::mutable_buffer, 54 MutableBufferSequence> bufs(o->buffers_); 55 56 std::size_t addr_len = o->sender_endpoint_.capacity(); 57 status result = socket_ops::non_blocking_recvfrom(o->socket_, 58 bufs.buffers(), bufs.count(), o->flags_, 59 o->sender_endpoint_.data(), &addr_len, 60 o->ec_, o->bytes_transferred_) ? done : not_done; 61 62 if (result && !o->ec_) 63 o->sender_endpoint_.resize(addr_len); 64 65 BOOST_ASIO_HANDLER_REACTOR_OPERATION((*o, "non_blocking_recvfrom", 66 o->ec_, o->bytes_transferred_)); 67 68 return result; 69 } 70 71 private: 72 socket_type socket_; 73 int protocol_type_; 74 MutableBufferSequence buffers_; 75 Endpoint& sender_endpoint_; 76 socket_base::message_flags flags_; 77 }; 78 79 template <typename MutableBufferSequence, typename Endpoint, 80 typename Handler, typename IoExecutor> 81 class reactive_socket_recvfrom_op : 82 public reactive_socket_recvfrom_op_base<MutableBufferSequence, Endpoint> 83 { 84 public: 85 BOOST_ASIO_DEFINE_HANDLER_PTR(reactive_socket_recvfrom_op); 86 reactive_socket_recvfrom_op(socket_type socket,int protocol_type,const MutableBufferSequence & buffers,Endpoint & endpoint,socket_base::message_flags flags,Handler & handler,const IoExecutor & io_ex)87 reactive_socket_recvfrom_op(socket_type socket, int protocol_type, 88 const MutableBufferSequence& buffers, Endpoint& endpoint, 89 socket_base::message_flags flags, Handler& handler, 90 const IoExecutor& io_ex) 91 : reactive_socket_recvfrom_op_base<MutableBufferSequence, Endpoint>( 92 socket, protocol_type, buffers, endpoint, flags, 93 &reactive_socket_recvfrom_op::do_complete), 94 handler_(BOOST_ASIO_MOVE_CAST(Handler)(handler)), 95 io_executor_(io_ex) 96 { 97 handler_work<Handler, IoExecutor>::start(handler_, io_executor_); 98 } 99 do_complete(void * owner,operation * base,const boost::system::error_code &,std::size_t)100 static void do_complete(void* owner, operation* base, 101 const boost::system::error_code& /*ec*/, 102 std::size_t /*bytes_transferred*/) 103 { 104 // Take ownership of the handler object. 105 reactive_socket_recvfrom_op* o( 106 static_cast<reactive_socket_recvfrom_op*>(base)); 107 ptr p = { boost::asio::detail::addressof(o->handler_), o, o }; 108 handler_work<Handler, IoExecutor> w(o->handler_, o->io_executor_); 109 110 BOOST_ASIO_HANDLER_COMPLETION((*o)); 111 112 // Make a copy of the handler so that the memory can be deallocated before 113 // the upcall is made. Even if we're not about to make an upcall, a 114 // sub-object of the handler may be the true owner of the memory associated 115 // with the handler. Consequently, a local copy of the handler is required 116 // to ensure that any owning sub-object remains valid until after we have 117 // deallocated the memory here. 118 detail::binder2<Handler, boost::system::error_code, std::size_t> 119 handler(o->handler_, o->ec_, o->bytes_transferred_); 120 p.h = boost::asio::detail::addressof(handler.handler_); 121 p.reset(); 122 123 // Make the upcall if required. 124 if (owner) 125 { 126 fenced_block b(fenced_block::half); 127 BOOST_ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_)); 128 w.complete(handler, handler.handler_); 129 BOOST_ASIO_HANDLER_INVOCATION_END; 130 } 131 } 132 133 private: 134 Handler handler_; 135 IoExecutor io_executor_; 136 }; 137 138 } // namespace detail 139 } // namespace asio 140 } // namespace boost 141 142 #include <boost/asio/detail/pop_options.hpp> 143 144 #endif // BOOST_ASIO_DETAIL_REACTIVE_SOCKET_RECVFROM_OP_HPP 145