1//
2// detail/reactive_socket_recvfrom_op.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 ASIO_DETAIL_REACTIVE_SOCKET_RECVFROM_OP_HPP
12#define ASIO_DETAIL_REACTIVE_SOCKET_RECVFROM_OP_HPP
13
14
15#include "asio/detail/config.hpp"
16#include "asio/detail/addressof.hpp"
17#include "asio/detail/bind_handler.hpp"
18#include "asio/detail/buffer_sequence_adapter.hpp"
19#include "asio/detail/fenced_block.hpp"
20#include "asio/detail/reactor_op.hpp"
21#include "asio/detail/socket_ops.hpp"
22
23#include "asio/detail/push_options.hpp"
24
25namespace asio {
26namespace detail {
27
28template <typename MutableBufferSequence, typename Endpoint>
29class reactive_socket_recvfrom_op_base : public reactor_op
30{
31public:
32  reactive_socket_recvfrom_op_base(socket_type socket, int protocol_type,
33      const MutableBufferSequence& buffers, Endpoint& endpoint,
34      socket_base::message_flags flags, func_type complete_func)
35    : reactor_op(&reactive_socket_recvfrom_op_base::do_perform, complete_func),
36      socket_(socket),
37      protocol_type_(protocol_type),
38      buffers_(buffers),
39      sender_endpoint_(endpoint),
40      flags_(flags)
41  {
42  }
43
44  static bool do_perform(reactor_op* base)
45  {
46    reactive_socket_recvfrom_op_base* o(
47        static_cast<reactive_socket_recvfrom_op_base*>(base));
48
49    buffer_sequence_adapter<asio::mutable_buffer,
50        MutableBufferSequence> bufs(o->buffers_);
51
52    std::size_t addr_len = o->sender_endpoint_.capacity();
53    bool result = socket_ops::non_blocking_recvfrom(o->socket_,
54        bufs.buffers(), bufs.count(), o->flags_,
55        o->sender_endpoint_.data(), &addr_len,
56        o->ec_, o->bytes_transferred_);
57
58    if (result && !o->ec_)
59      o->sender_endpoint_.resize(addr_len);
60
61    return result;
62  }
63
64private:
65  socket_type socket_;
66  int protocol_type_;
67  MutableBufferSequence buffers_;
68  Endpoint& sender_endpoint_;
69  socket_base::message_flags flags_;
70};
71
72template <typename MutableBufferSequence, typename Endpoint, typename Handler>
73class reactive_socket_recvfrom_op :
74  public reactive_socket_recvfrom_op_base<MutableBufferSequence, Endpoint>
75{
76public:
77  ASIO_DEFINE_HANDLER_PTR(reactive_socket_recvfrom_op);
78
79  reactive_socket_recvfrom_op(socket_type socket, int protocol_type,
80      const MutableBufferSequence& buffers, Endpoint& endpoint,
81      socket_base::message_flags flags, Handler& handler)
82    : reactive_socket_recvfrom_op_base<MutableBufferSequence, Endpoint>(
83        socket, protocol_type, buffers, endpoint, flags,
84        &reactive_socket_recvfrom_op::do_complete),
85      handler_(ASIO_MOVE_CAST(Handler)(handler))
86  {
87  }
88
89  static void do_complete(io_service_impl* owner, operation* base,
90      const asio::error_code& /*ec*/,
91      std::size_t /*bytes_transferred*/)
92  {
93    // Take ownership of the handler object.
94    reactive_socket_recvfrom_op* o(
95        static_cast<reactive_socket_recvfrom_op*>(base));
96    ptr p = { asio::detail::addressof(o->handler_), o, o };
97
98    ASIO_HANDLER_COMPLETION((o));
99
100    // Make a copy of the handler so that the memory can be deallocated before
101    // the upcall is made. Even if we're not about to make an upcall, a
102    // sub-object of the handler may be the true owner of the memory associated
103    // with the handler. Consequently, a local copy of the handler is required
104    // to ensure that any owning sub-object remains valid until after we have
105    // deallocated the memory here.
106    detail::binder2<Handler, asio::error_code, std::size_t>
107      handler(o->handler_, o->ec_, o->bytes_transferred_);
108    p.h = asio::detail::addressof(handler.handler_);
109    p.reset();
110
111    // Make the upcall if required.
112    if (owner)
113    {
114      fenced_block b(fenced_block::half);
115      ASIO_HANDLER_INVOCATION_BEGIN((handler.arg1_, handler.arg2_));
116      asio_handler_invoke_helpers::invoke(handler, handler.handler_);
117      ASIO_HANDLER_INVOCATION_END;
118    }
119  }
120
121private:
122  Handler handler_;
123};
124
125} // namespace detail
126} // namespace asio
127
128#include "asio/detail/pop_options.hpp"
129
130#endif // ASIO_DETAIL_REACTIVE_SOCKET_RECVFROM_OP_HPP
131