include/boost/corosio/native/native_posix_descriptor.hpp

100.0% Lines (22 / 22) 100.0% Functions (14 / 14)

[ ] prev/next file

native_posix_descriptor.hpp

f(x) Functions (14)

Function Calls Lines Blocks

Line	Hits	Source Code
1		//
2		// Copyright (c) 2026 Michael Vandeberg
3		//
4		// Distributed under the Boost Software License, Version 1.0. (See accompanying
5		// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6		//
7		// Official repository: https://github.com/cppalliance/corosio
8		//
9
10		#ifndef BOOST_COROSIO_NATIVE_NATIVE_POSIX_DESCRIPTOR_HPP
11		#define BOOST_COROSIO_NATIVE_NATIVE_POSIX_DESCRIPTOR_HPP
12
13		#include <boost/corosio/detail/op_base.hpp>
14		#include <boost/corosio/posix_descriptor.hpp>
15		#include <boost/corosio/backend.hpp>
16
17		#if BOOST_COROSIO_POSIX \|\| defined(BOOST_COROSIO_MRDOCS)
18
19		#ifndef BOOST_COROSIO_MRDOCS
20		#if BOOST_COROSIO_HAS_EPOLL
21		#include <boost/corosio/native/detail/epoll/epoll_types.hpp>
22		#endif
23
24		#if BOOST_COROSIO_HAS_SELECT
25		#include <boost/corosio/native/detail/select/select_types.hpp>
26		#endif
27
28		#if BOOST_COROSIO_HAS_KQUEUE
29		#include <boost/corosio/native/detail/kqueue/kqueue_types.hpp>
30		#endif
31
32		#if BOOST_COROSIO_HAS_URING
33		// uring_types.hpp does not declare the descriptor: it was added
34		// after that header, in its own pair of files.
35		#include <boost/corosio/native/detail/uring/uring_descriptor_service.hpp>
36		#endif
37		#endif // !BOOST_COROSIO_MRDOCS
38
39		namespace boost::corosio {
40
41		/** Drives an already-open POSIX descriptor, calling the backend directly.
42
43		This class template inherits from @ref posix_descriptor and
44		shadows the async operations (`read_some`, `write_some`, `wait`)
45		with versions that call the backend implementation directly.
46		This lets the compiler inline through the entire call chain.
47
48		Non-async operations (`assign`, `release`, `close`, `cancel`)
49		remain unchanged and dispatch through the compiled library.
50
51		A `native_posix_descriptor` IS-A `posix_descriptor` and can be
52		passed to any function expecting `posix_descriptor&` or
53		`io_stream&`, in which case virtual dispatch is used
54		transparently.
55
56		@tparam Backend A backend tag value (e.g., `epoll`) whose type
57		provides the concrete implementation types.
58
59		@par Thread Safety
60		Same as @ref posix_descriptor.
61
62		@par Example
63		@par !example assign_and_wait
64
65		@see posix_descriptor, epoll_t, kqueue_t
66		*/
67		template<auto Backend>
68		class native_posix_descriptor : public posix_descriptor
69		{
70		using backend_type = decltype(Backend);
71		using impl_type = typename backend_type::descriptor_type;
72		using service_type = typename backend_type::descriptor_service_type;
73
74	6x	impl_type& get_impl() noexcept
75		{
76	6x	return static_cast<impl_type>(h_.get());
77		}
78
79		template<class MutableBufferSequence>
80		struct native_read_awaitable
81		: detail::bytes_op_base<native_read_awaitable<MutableBufferSequence>>
82		{
83		native_posix_descriptor& self_;
84		MutableBufferSequence buffers_;
85
86	6x	native_read_awaitable(
87		native_posix_descriptor& self,
88		MutableBufferSequence buffers) noexcept
89	6x	: self_(self)
90	6x	, buffers_(std::move(buffers))
91		{
92	6x	}
93
94		std::coroutine_handle<>
95	4x	dispatch(std::coroutine_handle<> h, capy::executor_ref ex) const
96		{
97	12x	return self_.get_impl().read_some(
98	12x	h, ex, buffers_, this->token_, &this->ec_, &this->bytes_);
99		}
100		};
101
102		template<class ConstBufferSequence>
103		struct native_write_awaitable
104		: detail::bytes_op_base<native_write_awaitable<ConstBufferSequence>>
105		{
106		native_posix_descriptor& self_;
107		ConstBufferSequence buffers_;
108
109		native_write_awaitable(
110		native_posix_descriptor& self, ConstBufferSequence buffers) noexcept
111		: self_(self)
112		, buffers_(std::move(buffers))
113		{
114		}
115
116		std::coroutine_handle<>
117		dispatch(std::coroutine_handle<> h, capy::executor_ref ex) const
118		{
119		return self_.get_impl().write_some(
120		h, ex, buffers_, this->token_, &this->ec_, &this->bytes_);
121		}
122		};
123
124		struct native_wait_awaitable : detail::void_op_base<native_wait_awaitable>
125		{
126		native_posix_descriptor& self_;
127		wait_type w_;
128
129	4x	native_wait_awaitable(
130		native_posix_descriptor& self, wait_type w) noexcept
131	4x	: self_(self)
132	4x	, w_(w)
133		{
134	4x	}
135
136		std::coroutine_handle<>
137	2x	dispatch(std::coroutine_handle<> h, capy::executor_ref ex) const
138		{
139	2x	return self_.get_impl().wait(h, ex, w_, this->token_, &this->ec_);
140		}
141		};
142
143		public:
144		/** Construct a native descriptor from an execution context.
145
146		@param ctx The execution context that owns this object.
147		*/
148	12x	explicit native_posix_descriptor(capy::execution_context& ctx)
149	12x	: io_object(handle(ctx, ctx.use_service<service_type>()))
150		{
151	12x	}
152
153		/** Construct a native descriptor from an executor.
154
155		@param ex The executor whose context owns this object.
156		*/
157		template<class Ex>
158		requires(!std::same_as<
159		std::remove_cvref_t<Ex>,
160		native_posix_descriptor>) &&
161		capy::Executor<Ex>
162		explicit native_posix_descriptor(Ex const& ex)
163		: native_posix_descriptor(ex.context())
164		{
165		}
166
167		/// Move construct.
168		native_posix_descriptor(native_posix_descriptor&&) noexcept = default;
169
170		/// Move assign.
171		native_posix_descriptor&
172		operator=(native_posix_descriptor&&) noexcept = default;
173
174		/// Copy construction is disabled; the handle is uniquely owned.
175		native_posix_descriptor(native_posix_descriptor const&) = delete;
176		/// Copy assignment is disabled; the handle is uniquely owned.
177		native_posix_descriptor&
178		operator=(native_posix_descriptor const&) = delete;
179
180		/** Asynchronously read data from the descriptor.
181
182		Calls the backend implementation directly, bypassing virtual
183		dispatch. Otherwise identical to @ref io_stream::read_some.
184
185		@param buffers The buffer sequence to read into.
186
187		@return An awaitable yielding `(error_code, std::size_t)`.
188		*/
189		template<capy::MutableBufferSequence MB>
190	6x	[[nodiscard]] auto read_some(MB const& buffers)
191		{
192	6x	return native_read_awaitable<MB>(*this, buffers);
193		}
194
195		/** Asynchronously write data to the descriptor.
196
197		Calls the backend implementation directly, bypassing virtual
198		dispatch. Otherwise identical to @ref io_stream::write_some.
199
200		@param buffers The buffer sequence to write from.
201
202		@return An awaitable yielding `(error_code, std::size_t)`.
203		*/
204		template<capy::ConstBufferSequence CB>
205		[[nodiscard]] auto write_some(CB const& buffers)
206		{
207		return native_write_awaitable<CB>(*this, buffers);
208		}
209
210		/** Wait for readiness without transferring bytes.
211
212		Calls the backend implementation directly, bypassing virtual
213		dispatch. Otherwise identical to @ref posix_descriptor::wait.
214
215		@param w The direction to wait on.
216
217		@return An awaitable yielding `io_result<>`.
218		*/
219	4x	[[nodiscard]] auto wait(wait_type w)
220		{
221	4x	return native_wait_awaitable(*this, w);
222		}
223		};
224
225		} // namespace boost::corosio
226
227		#endif // BOOST_COROSIO_POSIX \|\| BOOST_COROSIO_MRDOCS
228
229		#endif // BOOST_COROSIO_NATIVE_NATIVE_POSIX_DESCRIPTOR_HPP
230