include/boost/corosio/native/detail/iocp/win_overlapped_op.hpp

91.8% Lines (45/49) 88.9% List of functions (8/9) 90.0% Branches (9/10)

[ ] prev/next file n p prev/next uncovered line

win_overlapped_op.hpp

f(x) Functions (9)

Function Calls Lines Branches Blocks

Line	Branch	Hits	Source Code
1			//
2			// Copyright (c) 2025 Vinnie Falco ([email protected])
3			// Copyright (c) 2026 Steve Gerbino
4			// Copyright (c) 2026 Michael Vandeberg
5			//
6			// Distributed under the Boost Software License, Version 1.0. (See accompanying
7			// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
8			//
9			// Official repository: https://github.com/cppalliance/corosio
10			//
11
12			#ifndef BOOST_COROSIO_NATIVE_DETAIL_IOCP_WIN_OVERLAPPED_OP_HPP
13			#define BOOST_COROSIO_NATIVE_DETAIL_IOCP_WIN_OVERLAPPED_OP_HPP
14
15			#include <boost/corosio/detail/platform.hpp>
16
17			#if BOOST_COROSIO_HAS_IOCP
18
19			#include <boost/corosio/detail/config.hpp>
20			#include <boost/capy/error.hpp>
21			#include <system_error>
22
23			#include <boost/corosio/native/detail/make_err.hpp>
24			#include <boost/corosio/detail/dispatch_coro.hpp>
25			#include <boost/corosio/native/detail/coro_op.hpp>
26			#include <boost/corosio/native/detail/coro_op_complete.hpp>
27
28			#include <atomic>
29			#include <coroutine>
30			#include <cstddef>
31
32			#include <boost/corosio/native/detail/iocp/win_windows.hpp>
33
34			namespace boost::corosio::detail {
35
36			/** Base class for IOCP overlapped operations.
37
38			Derives from both OVERLAPPED (for Windows IOCP) and scheduler_op
39			(for queueing). Uses function pointer dispatch inherited from
40			scheduler_op - no virtual functions.
41
42			The OVERLAPPED structure is at the start so we can static_cast
43			between OVERLAPPED* and overlapped_op*.
44			*/
45			struct overlapped_op
46			: OVERLAPPED
47			, coro_op
48			{
49			/** Function pointer type for cancellation hook. */
50			using cancel_func_type = void ()(overlapped_op) noexcept;
51
52			long ready_ = 0;
53			DWORD dwError = 0;
54			DWORD bytes_transferred = 0;
55			cancel_func_type cancel_func_ = nullptr;
56
57		20855x	explicit overlapped_op(func_type func) noexcept : coro_op(func)
58			{
59		20855x	reset_overlapped();
60		20855x	}
61
62		611892x	void reset_overlapped() noexcept
63			{
64		611892x	Internal = 0;
65		611892x	InternalHigh = 0;
66		611892x	Offset = 0;
67		611892x	OffsetHigh = 0;
68		611892x	hEvent = nullptr;
69		611892x	}
70
71		591037x	void reset() noexcept
72			{
73		591037x	reset_overlapped();
74		591037x	ready_ = 0;
75		591037x	dwError = 0;
76		591037x	bytes_transferred = 0;
77		591037x	empty_buffer = false;
78		591037x	is_read = false;
79		591037x	cancelled.store(false, std::memory_order_relaxed);
80		591037x	}
81
82			// coro_op::request_cancel() (set the cancelled flag) is inherited
83			// and used directly by close()/cancel() paths. The stop_token path
84			// additionally drives the kernel via on_cancel() below.
85
86		942x	void do_cancel() noexcept
87			{
88	2/2 ✓ Branch 2 → 3 taken 940 times. ✓ Branch 2 → 4 taken 2 times.	942x	if (cancel_func_)
89		940x	cancel_func_(this);
90		942x	}
91
92			/** IOCP cancellation hook (stop_token path): set the flag, then issue
93			the registered CancelIoEx / wait-reactor deregister via cancel_func_. */
94		942x	void on_cancel() noexcept override
95			{
96		942x	request_cancel();
97		942x	do_cancel();
98		942x	}
99
100		591003x	void store_result(DWORD bytes, DWORD err) noexcept
101			{
102		591003x	bytes_transferred = bytes;
103		591003x	dwError = err;
104		591003x	}
105
106			/** Write results to output parameters and resume coroutine. */
107		589461x	void invoke_handler()
108			{
109		589461x	stop_cb.reset();
110
111		1176881x	decode_io_result(
112			ec_out,
113		589461x	cancelled.load(std::memory_order_acquire),
114		2041x	dwError != 0 ? make_err(dwError) : std::error_code{},
115		589461x	is_read, static_cast<std::size_t>(bytes_transferred),
116	2/2 ✓ Branch 3 → 4 taken 2041 times. ✓ Branch 3 → 5 taken 587420 times.	589461x	empty_buffer);
117
118	2/2 ✓ Branch 8 → 9 taken 588041 times. ✓ Branch 8 → 10 taken 1420 times.	589461x	if (bytes_out)
119		588041x	*bytes_out = static_cast<std::size_t>(bytes_transferred);
120
121		589461x	cont_op.cont.h = h;
122	2/2 ✓ Branch 10 → 11 taken 589461 times. ✓ Branch 11 → 12 taken 589461 times.	589461x	dispatch_coro(ex, cont_op.cont).resume();
123		589461x	}
124
125			/** Disarm cancellation and abandon the coroutine handle. */
126		✗	void cleanup_only()
127			{
128		✗	stop_cb.reset();
129		✗	h = {};
130		✗	}
131			};
132
133			/** Cast OVERLAPPED* to overlapped_op*.
134
135			Safe because overlapped_op has OVERLAPPED as first base class.
136			*/
137			inline overlapped_op*
138		591007x	overlapped_to_op(LPOVERLAPPED ov) noexcept
139			{
140	1/2 ✓ Branch 2 → 3 taken 591007 times. ✗ Branch 2 → 4 not taken.	591007x	return static_cast<overlapped_op*>(ov);
141			}
142
143			} // namespace boost::corosio::detail
144
145			#endif // BOOST_COROSIO_HAS_IOCP
146
147			#endif // BOOST_COROSIO_NATIVE_DETAIL_IOCP_WIN_OVERLAPPED_OP_HPP
148