include/boost/corosio/native/detail/reactor/reactor_descriptor_ops.hpp

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reactor_descriptor_ops.hpp

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boost::corosio::detail::descriptor_write_policy::write(int, iovec*, int) :37 4x 100.0% 66.7% 88.0% boost::corosio::detail::descriptor_write_policy::write_one(int, void const*, unsigned long) :50 18x 100.0% 66.7% 88.0%

Line	Branch	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_DETAIL_REACTOR_REACTOR_DESCRIPTOR_OPS_HPP
11			#define BOOST_COROSIO_NATIVE_DETAIL_REACTOR_REACTOR_DESCRIPTOR_OPS_HPP
12
13			#include <boost/corosio/detail/platform.hpp>
14
15			#if BOOST_COROSIO_POSIX
16
17			#include <cstddef>
18
19			#include <errno.h>
20			#include <sys/types.h>
21			#include <sys/uio.h>
22			#include <unistd.h>
23
24			namespace boost::corosio::detail {
25
26			/* Write policy shared by every reactor backend's descriptor ops.
27
28			Descriptors are not sockets: sendmsg() fails with ENOTSOCK on a pipe
29			or character device, so the write path is writev()/write() and
30			SIGPIPE suppression is structurally unavailable -- MSG_NOSIGNAL is a
31			send() flag and SO_NOSIGPIPE a socket option. A write to a pipe whose
32			read end has closed raises SIGPIPE, exactly as a plain write(2)
33			would; callers install SIG_IGN.
34			*/
35			struct descriptor_write_policy
36			{
37		4x	static ssize_t write(int fd, iovec* iovecs, int count) noexcept
38			{
39			ssize_t n;
40		4x	do
41			{
42	1/2 ✓ Branch 0 taken 4 times. ✗ Branch 1 not taken.	4x	n = ::writev(fd, iovecs, count);
43		8x	}
44	3/4 ✓ Branch 0 taken 2 times. ✓ Branch 1 taken 2 times. ✓ Branch 2 taken 2 times. ✗ Branch 3 not taken.	4x	while (n < 0 && errno == EINTR);
45		4x	return n;
46			}
47
48			// Single-buffer fast path: skips the kernel's iov_iter setup.
49			static ssize_t
50		18x	write_one(int fd, void const* data, std::size_t size) noexcept
51			{
52			ssize_t n;
53		18x	do
54			{
55	1/2 ✓ Branch 0 taken 18 times. ✗ Branch 1 not taken.	18x	n = ::write(fd, data, size);
56		36x	}
57	3/4 ✓ Branch 0 taken 8 times. ✓ Branch 1 taken 10 times. ✓ Branch 2 taken 8 times. ✗ Branch 3 not taken.	18x	while (n < 0 && errno == EINTR);
58		18x	return n;
59			}
60			};
61
62			} // namespace boost::corosio::detail
63
64			#endif // BOOST_COROSIO_POSIX
65
66			#endif // BOOST_COROSIO_NATIVE_DETAIL_REACTOR_REACTOR_DESCRIPTOR_OPS_HPP
67