1 //
2 // detail/reactive_socket_service_base.hpp
3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4 //
5 // Copyright (c) 2003-2021 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_SERVICE_BASE_HPP
12 #define BOOST_ASIO_DETAIL_REACTIVE_SOCKET_SERVICE_BASE_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 
20 #if !defined(BOOST_ASIO_HAS_IOCP) \
21   && !defined(BOOST_ASIO_WINDOWS_RUNTIME)
22 
23 #include <boost/asio/buffer.hpp>
24 #include <boost/asio/error.hpp>
25 #include <boost/asio/execution_context.hpp>
26 #include <boost/asio/socket_base.hpp>
27 #include <boost/asio/detail/buffer_sequence_adapter.hpp>
28 #include <boost/asio/detail/memory.hpp>
29 #include <boost/asio/detail/reactive_null_buffers_op.hpp>
30 #include <boost/asio/detail/reactive_socket_recv_op.hpp>
31 #include <boost/asio/detail/reactive_socket_recvmsg_op.hpp>
32 #include <boost/asio/detail/reactive_socket_send_op.hpp>
33 #include <boost/asio/detail/reactive_wait_op.hpp>
34 #include <boost/asio/detail/reactor.hpp>
35 #include <boost/asio/detail/reactor_op.hpp>
36 #include <boost/asio/detail/socket_holder.hpp>
37 #include <boost/asio/detail/socket_ops.hpp>
38 #include <boost/asio/detail/socket_types.hpp>
39 
40 #include <boost/asio/detail/push_options.hpp>
41 
42 namespace boost {
43 namespace asio {
44 namespace detail {
45 
46 class reactive_socket_service_base
47 {
48 public:
49   // The native type of a socket.
50   typedef socket_type native_handle_type;
51 
52   // The implementation type of the socket.
53   struct base_implementation_type
54   {
55     // The native socket representation.
56     socket_type socket_;
57 
58     // The current state of the socket.
59     socket_ops::state_type state_;
60 
61     // Per-descriptor data used by the reactor.
62     reactor::per_descriptor_data reactor_data_;
63   };
64 
65   // Constructor.
66   BOOST_ASIO_DECL reactive_socket_service_base(execution_context& context);
67 
68   // Destroy all user-defined handler objects owned by the service.
69   BOOST_ASIO_DECL void base_shutdown();
70 
71   // Construct a new socket implementation.
72   BOOST_ASIO_DECL void construct(base_implementation_type& impl);
73 
74   // Move-construct a new socket implementation.
75   BOOST_ASIO_DECL void base_move_construct(base_implementation_type& impl,
76       base_implementation_type& other_impl) BOOST_ASIO_NOEXCEPT;
77 
78   // Move-assign from another socket implementation.
79   BOOST_ASIO_DECL void base_move_assign(base_implementation_type& impl,
80       reactive_socket_service_base& other_service,
81       base_implementation_type& other_impl);
82 
83   // Destroy a socket implementation.
84   BOOST_ASIO_DECL void destroy(base_implementation_type& impl);
85 
86   // Determine whether the socket is open.
is_open(const base_implementation_type & impl) const87   bool is_open(const base_implementation_type& impl) const
88   {
89     return impl.socket_ != invalid_socket;
90   }
91 
92   // Destroy a socket implementation.
93   BOOST_ASIO_DECL boost::system::error_code close(
94       base_implementation_type& impl, boost::system::error_code& ec);
95 
96   // Release ownership of the socket.
97   BOOST_ASIO_DECL socket_type release(
98       base_implementation_type& impl, boost::system::error_code& ec);
99 
100   // Get the native socket representation.
native_handle(base_implementation_type & impl)101   native_handle_type native_handle(base_implementation_type& impl)
102   {
103     return impl.socket_;
104   }
105 
106   // Cancel all operations associated with the socket.
107   BOOST_ASIO_DECL boost::system::error_code cancel(
108       base_implementation_type& impl, boost::system::error_code& ec);
109 
110   // Determine whether the socket is at the out-of-band data mark.
at_mark(const base_implementation_type & impl,boost::system::error_code & ec) const111   bool at_mark(const base_implementation_type& impl,
112       boost::system::error_code& ec) const
113   {
114     return socket_ops::sockatmark(impl.socket_, ec);
115   }
116 
117   // Determine the number of bytes available for reading.
available(const base_implementation_type & impl,boost::system::error_code & ec) const118   std::size_t available(const base_implementation_type& impl,
119       boost::system::error_code& ec) const
120   {
121     return socket_ops::available(impl.socket_, ec);
122   }
123 
124   // Place the socket into the state where it will listen for new connections.
listen(base_implementation_type & impl,int backlog,boost::system::error_code & ec)125   boost::system::error_code listen(base_implementation_type& impl,
126       int backlog, boost::system::error_code& ec)
127   {
128     socket_ops::listen(impl.socket_, backlog, ec);
129     return ec;
130   }
131 
132   // Perform an IO control command on the socket.
133   template <typename IO_Control_Command>
io_control(base_implementation_type & impl,IO_Control_Command & command,boost::system::error_code & ec)134   boost::system::error_code io_control(base_implementation_type& impl,
135       IO_Control_Command& command, boost::system::error_code& ec)
136   {
137     socket_ops::ioctl(impl.socket_, impl.state_, command.name(),
138         static_cast<ioctl_arg_type*>(command.data()), ec);
139     return ec;
140   }
141 
142   // Gets the non-blocking mode of the socket.
non_blocking(const base_implementation_type & impl) const143   bool non_blocking(const base_implementation_type& impl) const
144   {
145     return (impl.state_ & socket_ops::user_set_non_blocking) != 0;
146   }
147 
148   // Sets the non-blocking mode of the socket.
non_blocking(base_implementation_type & impl,bool mode,boost::system::error_code & ec)149   boost::system::error_code non_blocking(base_implementation_type& impl,
150       bool mode, boost::system::error_code& ec)
151   {
152     socket_ops::set_user_non_blocking(impl.socket_, impl.state_, mode, ec);
153     return ec;
154   }
155 
156   // Gets the non-blocking mode of the native socket implementation.
native_non_blocking(const base_implementation_type & impl) const157   bool native_non_blocking(const base_implementation_type& impl) const
158   {
159     return (impl.state_ & socket_ops::internal_non_blocking) != 0;
160   }
161 
162   // Sets the non-blocking mode of the native socket implementation.
native_non_blocking(base_implementation_type & impl,bool mode,boost::system::error_code & ec)163   boost::system::error_code native_non_blocking(base_implementation_type& impl,
164       bool mode, boost::system::error_code& ec)
165   {
166     socket_ops::set_internal_non_blocking(impl.socket_, impl.state_, mode, ec);
167     return ec;
168   }
169 
170   // Wait for the socket to become ready to read, ready to write, or to have
171   // pending error conditions.
wait(base_implementation_type & impl,socket_base::wait_type w,boost::system::error_code & ec)172   boost::system::error_code wait(base_implementation_type& impl,
173       socket_base::wait_type w, boost::system::error_code& ec)
174   {
175     switch (w)
176     {
177     case socket_base::wait_read:
178       socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
179       break;
180     case socket_base::wait_write:
181       socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
182       break;
183     case socket_base::wait_error:
184       socket_ops::poll_error(impl.socket_, impl.state_, -1, ec);
185       break;
186     default:
187       ec = boost::asio::error::invalid_argument;
188       break;
189     }
190 
191     return ec;
192   }
193 
194   // Asynchronously wait for the socket to become ready to read, ready to
195   // write, or to have pending error conditions.
196   template <typename Handler, typename IoExecutor>
async_wait(base_implementation_type & impl,socket_base::wait_type w,Handler & handler,const IoExecutor & io_ex)197   void async_wait(base_implementation_type& impl,
198       socket_base::wait_type w, Handler& handler, const IoExecutor& io_ex)
199   {
200     bool is_continuation =
201       boost_asio_handler_cont_helpers::is_continuation(handler);
202 
203     // Allocate and construct an operation to wrap the handler.
204     typedef reactive_wait_op<Handler, IoExecutor> op;
205     typename op::ptr p = { boost::asio::detail::addressof(handler),
206       op::ptr::allocate(handler), 0 };
207     p.p = new (p.v) op(success_ec_, handler, io_ex);
208 
209     BOOST_ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
210           &impl, impl.socket_, "async_wait"));
211 
212     int op_type;
213     switch (w)
214     {
215       case socket_base::wait_read:
216         op_type = reactor::read_op;
217         break;
218       case socket_base::wait_write:
219         op_type = reactor::write_op;
220         break;
221       case socket_base::wait_error:
222         op_type = reactor::except_op;
223         break;
224       default:
225         p.p->ec_ = boost::asio::error::invalid_argument;
226         reactor_.post_immediate_completion(p.p, is_continuation);
227         p.v = p.p = 0;
228         return;
229     }
230 
231     start_op(impl, op_type, p.p, is_continuation, false, false);
232     p.v = p.p = 0;
233   }
234 
235   // Send the given data to the peer.
236   template <typename ConstBufferSequence>
send(base_implementation_type & impl,const ConstBufferSequence & buffers,socket_base::message_flags flags,boost::system::error_code & ec)237   size_t send(base_implementation_type& impl,
238       const ConstBufferSequence& buffers,
239       socket_base::message_flags flags, boost::system::error_code& ec)
240   {
241     typedef buffer_sequence_adapter<boost::asio::const_buffer,
242         ConstBufferSequence> bufs_type;
243 
244     if (bufs_type::is_single_buffer)
245     {
246       return socket_ops::sync_send1(impl.socket_,
247           impl.state_, bufs_type::first(buffers).data(),
248           bufs_type::first(buffers).size(), flags, ec);
249     }
250     else
251     {
252       bufs_type bufs(buffers);
253       return socket_ops::sync_send(impl.socket_, impl.state_,
254           bufs.buffers(), bufs.count(), flags, bufs.all_empty(), ec);
255     }
256   }
257 
258   // Wait until data can be sent without blocking.
send(base_implementation_type & impl,const null_buffers &,socket_base::message_flags,boost::system::error_code & ec)259   size_t send(base_implementation_type& impl, const null_buffers&,
260       socket_base::message_flags, boost::system::error_code& ec)
261   {
262     // Wait for socket to become ready.
263     socket_ops::poll_write(impl.socket_, impl.state_, -1, ec);
264 
265     return 0;
266   }
267 
268   // Start an asynchronous send. The data being sent must be valid for the
269   // lifetime of the asynchronous operation.
270   template <typename ConstBufferSequence, typename Handler, typename IoExecutor>
async_send(base_implementation_type & impl,const ConstBufferSequence & buffers,socket_base::message_flags flags,Handler & handler,const IoExecutor & io_ex)271   void async_send(base_implementation_type& impl,
272       const ConstBufferSequence& buffers, socket_base::message_flags flags,
273       Handler& handler, const IoExecutor& io_ex)
274   {
275     bool is_continuation =
276       boost_asio_handler_cont_helpers::is_continuation(handler);
277 
278     // Allocate and construct an operation to wrap the handler.
279     typedef reactive_socket_send_op<
280         ConstBufferSequence, Handler, IoExecutor> op;
281     typename op::ptr p = { boost::asio::detail::addressof(handler),
282       op::ptr::allocate(handler), 0 };
283     p.p = new (p.v) op(success_ec_, impl.socket_,
284         impl.state_, buffers, flags, handler, io_ex);
285 
286     BOOST_ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
287           &impl, impl.socket_, "async_send"));
288 
289     start_op(impl, reactor::write_op, p.p, is_continuation, true,
290         ((impl.state_ & socket_ops::stream_oriented)
291           && buffer_sequence_adapter<boost::asio::const_buffer,
292             ConstBufferSequence>::all_empty(buffers)));
293     p.v = p.p = 0;
294   }
295 
296   // Start an asynchronous wait until data can be sent without blocking.
297   template <typename Handler, typename IoExecutor>
async_send(base_implementation_type & impl,const null_buffers &,socket_base::message_flags,Handler & handler,const IoExecutor & io_ex)298   void async_send(base_implementation_type& impl, const null_buffers&,
299       socket_base::message_flags, Handler& handler, const IoExecutor& io_ex)
300   {
301     bool is_continuation =
302       boost_asio_handler_cont_helpers::is_continuation(handler);
303 
304     // Allocate and construct an operation to wrap the handler.
305     typedef reactive_null_buffers_op<Handler, IoExecutor> op;
306     typename op::ptr p = { boost::asio::detail::addressof(handler),
307       op::ptr::allocate(handler), 0 };
308     p.p = new (p.v) op(success_ec_, handler, io_ex);
309 
310     BOOST_ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
311           &impl, impl.socket_, "async_send(null_buffers)"));
312 
313     start_op(impl, reactor::write_op, p.p, is_continuation, false, false);
314     p.v = p.p = 0;
315   }
316 
317   // Receive some data from the peer. Returns the number of bytes received.
318   template <typename MutableBufferSequence>
receive(base_implementation_type & impl,const MutableBufferSequence & buffers,socket_base::message_flags flags,boost::system::error_code & ec)319   size_t receive(base_implementation_type& impl,
320       const MutableBufferSequence& buffers,
321       socket_base::message_flags flags, boost::system::error_code& ec)
322   {
323     typedef buffer_sequence_adapter<boost::asio::mutable_buffer,
324         MutableBufferSequence> bufs_type;
325 
326     if (bufs_type::is_single_buffer)
327     {
328       return socket_ops::sync_recv1(impl.socket_,
329           impl.state_, bufs_type::first(buffers).data(),
330           bufs_type::first(buffers).size(), flags, ec);
331     }
332     else
333     {
334       bufs_type bufs(buffers);
335       return socket_ops::sync_recv(impl.socket_, impl.state_,
336           bufs.buffers(), bufs.count(), flags, bufs.all_empty(), ec);
337     }
338   }
339 
340   // Wait until data can be received without blocking.
receive(base_implementation_type & impl,const null_buffers &,socket_base::message_flags,boost::system::error_code & ec)341   size_t receive(base_implementation_type& impl, const null_buffers&,
342       socket_base::message_flags, boost::system::error_code& ec)
343   {
344     // Wait for socket to become ready.
345     socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
346 
347     return 0;
348   }
349 
350   // Start an asynchronous receive. The buffer for the data being received
351   // must be valid for the lifetime of the asynchronous operation.
352   template <typename MutableBufferSequence,
353       typename Handler, typename IoExecutor>
async_receive(base_implementation_type & impl,const MutableBufferSequence & buffers,socket_base::message_flags flags,Handler & handler,const IoExecutor & io_ex)354   void async_receive(base_implementation_type& impl,
355       const MutableBufferSequence& buffers, socket_base::message_flags flags,
356       Handler& handler, const IoExecutor& io_ex)
357   {
358     bool is_continuation =
359       boost_asio_handler_cont_helpers::is_continuation(handler);
360 
361     // Allocate and construct an operation to wrap the handler.
362     typedef reactive_socket_recv_op<
363         MutableBufferSequence, Handler, IoExecutor> op;
364     typename op::ptr p = { boost::asio::detail::addressof(handler),
365       op::ptr::allocate(handler), 0 };
366     p.p = new (p.v) op(success_ec_, impl.socket_,
367         impl.state_, buffers, flags, handler, io_ex);
368 
369     BOOST_ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
370           &impl, impl.socket_, "async_receive"));
371 
372     start_op(impl,
373         (flags & socket_base::message_out_of_band)
374           ? reactor::except_op : reactor::read_op,
375         p.p, is_continuation,
376         (flags & socket_base::message_out_of_band) == 0,
377         ((impl.state_ & socket_ops::stream_oriented)
378           && buffer_sequence_adapter<boost::asio::mutable_buffer,
379             MutableBufferSequence>::all_empty(buffers)));
380     p.v = p.p = 0;
381   }
382 
383   // Wait until data can be received without blocking.
384   template <typename Handler, typename IoExecutor>
async_receive(base_implementation_type & impl,const null_buffers &,socket_base::message_flags flags,Handler & handler,const IoExecutor & io_ex)385   void async_receive(base_implementation_type& impl,
386       const null_buffers&, socket_base::message_flags flags,
387       Handler& handler, const IoExecutor& io_ex)
388   {
389     bool is_continuation =
390       boost_asio_handler_cont_helpers::is_continuation(handler);
391 
392     // Allocate and construct an operation to wrap the handler.
393     typedef reactive_null_buffers_op<Handler, IoExecutor> op;
394     typename op::ptr p = { boost::asio::detail::addressof(handler),
395       op::ptr::allocate(handler), 0 };
396     p.p = new (p.v) op(success_ec_, handler, io_ex);
397 
398     BOOST_ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
399           &impl, impl.socket_, "async_receive(null_buffers)"));
400 
401     start_op(impl,
402         (flags & socket_base::message_out_of_band)
403           ? reactor::except_op : reactor::read_op,
404         p.p, is_continuation, false, false);
405     p.v = p.p = 0;
406   }
407 
408   // Receive some data with associated flags. Returns the number of bytes
409   // received.
410   template <typename MutableBufferSequence>
receive_with_flags(base_implementation_type & impl,const MutableBufferSequence & buffers,socket_base::message_flags in_flags,socket_base::message_flags & out_flags,boost::system::error_code & ec)411   size_t receive_with_flags(base_implementation_type& impl,
412       const MutableBufferSequence& buffers,
413       socket_base::message_flags in_flags,
414       socket_base::message_flags& out_flags, boost::system::error_code& ec)
415   {
416     buffer_sequence_adapter<boost::asio::mutable_buffer,
417         MutableBufferSequence> bufs(buffers);
418 
419     return socket_ops::sync_recvmsg(impl.socket_, impl.state_,
420         bufs.buffers(), bufs.count(), in_flags, out_flags, ec);
421   }
422 
423   // Wait until data can be received without blocking.
receive_with_flags(base_implementation_type & impl,const null_buffers &,socket_base::message_flags,socket_base::message_flags & out_flags,boost::system::error_code & ec)424   size_t receive_with_flags(base_implementation_type& impl,
425       const null_buffers&, socket_base::message_flags,
426       socket_base::message_flags& out_flags, boost::system::error_code& ec)
427   {
428     // Wait for socket to become ready.
429     socket_ops::poll_read(impl.socket_, impl.state_, -1, ec);
430 
431     // Clear out_flags, since we cannot give it any other sensible value when
432     // performing a null_buffers operation.
433     out_flags = 0;
434 
435     return 0;
436   }
437 
438   // Start an asynchronous receive. The buffer for the data being received
439   // must be valid for the lifetime of the asynchronous operation.
440   template <typename MutableBufferSequence,
441       typename Handler, typename IoExecutor>
async_receive_with_flags(base_implementation_type & impl,const MutableBufferSequence & buffers,socket_base::message_flags in_flags,socket_base::message_flags & out_flags,Handler & handler,const IoExecutor & io_ex)442   void async_receive_with_flags(base_implementation_type& impl,
443       const MutableBufferSequence& buffers, socket_base::message_flags in_flags,
444       socket_base::message_flags& out_flags, Handler& handler,
445       const IoExecutor& io_ex)
446   {
447     bool is_continuation =
448       boost_asio_handler_cont_helpers::is_continuation(handler);
449 
450     // Allocate and construct an operation to wrap the handler.
451     typedef reactive_socket_recvmsg_op<
452         MutableBufferSequence, Handler, IoExecutor> op;
453     typename op::ptr p = { boost::asio::detail::addressof(handler),
454       op::ptr::allocate(handler), 0 };
455     p.p = new (p.v) op(success_ec_, impl.socket_,
456         buffers, in_flags, out_flags, handler, io_ex);
457 
458     BOOST_ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
459           &impl, impl.socket_, "async_receive_with_flags"));
460 
461     start_op(impl,
462         (in_flags & socket_base::message_out_of_band)
463           ? reactor::except_op : reactor::read_op,
464         p.p, is_continuation,
465         (in_flags & socket_base::message_out_of_band) == 0, false);
466     p.v = p.p = 0;
467   }
468 
469   // Wait until data can be received without blocking.
470   template <typename Handler, typename IoExecutor>
async_receive_with_flags(base_implementation_type & impl,const null_buffers &,socket_base::message_flags in_flags,socket_base::message_flags & out_flags,Handler & handler,const IoExecutor & io_ex)471   void async_receive_with_flags(base_implementation_type& impl,
472       const null_buffers&, socket_base::message_flags in_flags,
473       socket_base::message_flags& out_flags, Handler& handler,
474       const IoExecutor& io_ex)
475   {
476     bool is_continuation =
477       boost_asio_handler_cont_helpers::is_continuation(handler);
478 
479     // Allocate and construct an operation to wrap the handler.
480     typedef reactive_null_buffers_op<Handler, IoExecutor> op;
481     typename op::ptr p = { boost::asio::detail::addressof(handler),
482       op::ptr::allocate(handler), 0 };
483     p.p = new (p.v) op(success_ec_, handler, io_ex);
484 
485     BOOST_ASIO_HANDLER_CREATION((reactor_.context(), *p.p, "socket",
486           &impl, impl.socket_, "async_receive_with_flags(null_buffers)"));
487 
488     // Clear out_flags, since we cannot give it any other sensible value when
489     // performing a null_buffers operation.
490     out_flags = 0;
491 
492     start_op(impl,
493         (in_flags & socket_base::message_out_of_band)
494           ? reactor::except_op : reactor::read_op,
495         p.p, is_continuation, false, false);
496     p.v = p.p = 0;
497   }
498 
499 protected:
500   // Open a new socket implementation.
501   BOOST_ASIO_DECL boost::system::error_code do_open(
502       base_implementation_type& impl, int af,
503       int type, int protocol, boost::system::error_code& ec);
504 
505   // Assign a native socket to a socket implementation.
506   BOOST_ASIO_DECL boost::system::error_code do_assign(
507       base_implementation_type& impl, int type,
508       const native_handle_type& native_socket, boost::system::error_code& ec);
509 
510   // Start the asynchronous read or write operation.
511   BOOST_ASIO_DECL void start_op(base_implementation_type& impl, int op_type,
512       reactor_op* op, bool is_continuation, bool is_non_blocking, bool noop);
513 
514   // Start the asynchronous accept operation.
515   BOOST_ASIO_DECL void start_accept_op(base_implementation_type& impl,
516       reactor_op* op, bool is_continuation, bool peer_is_open);
517 
518   // Start the asynchronous connect operation.
519   BOOST_ASIO_DECL void start_connect_op(base_implementation_type& impl,
520       reactor_op* op, bool is_continuation,
521       const socket_addr_type* addr, size_t addrlen);
522 
523   // The selector that performs event demultiplexing for the service.
524   reactor& reactor_;
525 
526   // Cached success value to avoid accessing category singleton.
527   const boost::system::error_code success_ec_;
528 };
529 
530 } // namespace detail
531 } // namespace asio
532 } // namespace boost
533 
534 #include <boost/asio/detail/pop_options.hpp>
535 
536 #if defined(BOOST_ASIO_HEADER_ONLY)
537 # include <boost/asio/detail/impl/reactive_socket_service_base.ipp>
538 #endif // defined(BOOST_ASIO_HEADER_ONLY)
539 
540 #endif // !defined(BOOST_ASIO_HAS_IOCP)
541        //   && !defined(BOOST_ASIO_WINDOWS_RUNTIME)
542 
543 #endif // BOOST_ASIO_DETAIL_REACTIVE_SOCKET_SERVICE_BASE_HPP
544