Index/include / boost / capy / io_result.hpp

include/boost/capy/io_result.hpp

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io_result.hpp
f(x) Functions (27)
Function Calls Lines Blocks
boost::capy::io_result<>::io_result() :56 680x 100.0% 100.0% boost::capy::io_result<int, double, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, bool>::io_result() :56 1x 100.0% 100.0% boost::capy::io_result<int>::io_result() :56 3x 100.0% 100.0% boost::capy::io_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >::io_result() :56 1x 100.0% 100.0% boost::capy::io_result<unsigned long>::io_result() :56 74x 100.0% 100.0% boost::capy::io_result<>::io_result(std::error_code) :59 341x 100.0% 100.0% boost::capy::io_result<boost::capy::(anonymous namespace)::throwing_move_payload>::io_result(std::error_code, boost::capy::(anonymous namespace)::throwing_move_payload) :59 1x 100.0% 100.0% boost::capy::io_result<boost::capy::async_mutex::lock_guard>::io_result(std::error_code, boost::capy::async_mutex::lock_guard) :59 4x 100.0% 100.0% boost::capy::io_result<int, double, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >::io_result(std::error_code, int, double, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >) :59 1x 100.0% 100.0% boost::capy::io_result<int, double, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, bool>::io_result(std::error_code, int, double, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, bool) :59 1x 100.0% 100.0% boost::capy::io_result<int, double>::io_result(std::error_code, int, double) :59 4x 100.0% 100.0% boost::capy::io_result<int, int, int>::io_result(std::error_code, int, int, int) :59 3x 100.0% 100.0% boost::capy::io_result<int>::io_result(std::error_code, int) :59 6x 100.0% 100.0% boost::capy::io_result<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >::io_result(std::error_code, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >) :59 8x 100.0% 100.0% boost::capy::io_result<std::span<boost::capy::const_buffer, 18446744073709551615ul> >::io_result(std::error_code, std::span<boost::capy::const_buffer, 18446744073709551615ul>) :59 551x 100.0% 100.0% boost::capy::io_result<std::tuple<>, std::tuple<> >::io_result(std::error_code, std::tuple<>, std::tuple<>) :59 19x 100.0% 100.0% boost::capy::io_result<std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > >::io_result(std::error_code, std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >) :59 1x 100.0% 100.0% boost::capy::io_result<std::vector<unsigned long, std::allocator<unsigned long> > >::io_result(std::error_code, std::vector<unsigned long, std::allocator<unsigned long> >) :59 9x 100.0% 100.0% boost::capy::io_result<std::vector<unsigned long, std::allocator<unsigned long> >, unsigned long>::io_result(std::error_code, std::vector<unsigned long, std::allocator<unsigned long> >, unsigned long) :59 1x 100.0% 100.0% boost::capy::io_result<unsigned long, int>::io_result(std::error_code, unsigned long, int) :59 1x 100.0% 100.0% boost::capy::io_result<unsigned long, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >::io_result(std::error_code, unsigned long, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >) :59 1x 100.0% 100.0% boost::capy::io_result<unsigned long, std::tuple<> >::io_result(std::error_code, unsigned long, std::tuple<>) :59 1x 100.0% 100.0% boost::capy::io_result<unsigned long, std::tuple<unsigned long, int> >::io_result(std::error_code, unsigned long, std::tuple<unsigned long, int>) :59 1x 100.0% 100.0% boost::capy::io_result<unsigned long, unsigned long, unsigned long>::io_result(std::error_code, unsigned long, unsigned long, unsigned long) :59 2x 100.0% 100.0% boost::capy::io_result<unsigned long, unsigned long>::io_result(std::error_code, unsigned long, unsigned long) :59 7x 100.0% 100.0% boost::capy::io_result<unsigned long>::io_result(std::error_code, unsigned long) :59 4981x 100.0% 100.0% decltype(auto) boost::capy::io_result<>::get<0ul>() && :83 72x 100.0% 100.0%
Line TLA Hits Source Code
1 //
2 // Copyright (c) 2025 Vinnie Falco (vinnie.falco@gmail.com)
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/capy
8 //
9
10 #ifndef BOOST_CAPY_IO_RESULT_HPP
11 #define BOOST_CAPY_IO_RESULT_HPP
12
13 #include <boost/capy/detail/config.hpp>
14 #include <system_error>
15
16 #include <cstddef>
17 #include <tuple>
18 #include <type_traits>
19 #include <utility>
20
21 namespace boost {
22 namespace capy {
23
24 /** Result type for asynchronous I/O operations.
25
26 This template provides a unified result type for async operations,
27 always containing a `std::error_code` plus optional additional
28 values. It supports structured bindings via the tuple protocol.
29
30 @par Example
31 @code
32 auto [ec, n] = co_await s.read_some(buf);
33 if (ec) { ... }
34 @endcode
35
36 @note Whether the payload is meaningful when `ec` is set is
37 defined by the operation that produced the result. Many I/O
38 operations report a meaningful partial result alongside `ec`
39 (for example, the number of bytes transferred before the
40 condition, as with EOF); others leave it unspecified.
41
42 @tparam Ts Ordered payload types following the leading
43 `std::error_code`.
44 */
45 template<class... Ts>
46 struct [[nodiscard]] io_result
47 {
48 /// The error code from the operation.
49 std::error_code ec;
50
51 /// The payload values. Their meaning when `ec` is set is defined
52 /// by the producing operation (see the class note).
53 std::tuple<Ts...> values;
54
55 /// Construct a default io_result.
56 759x io_result() = default;
57
58 /// Construct from an error code and payload values.
59 5944x io_result(std::error_code ec_, Ts... ts)
60 5944x : ec(ec_)
61 5603x , values(std::move(ts)...)
62 {
63 5944x }
64
65 /// @cond
66 template<std::size_t I>
67 decltype(auto) get() & noexcept
68 {
69 static_assert(I < 1 + sizeof...(Ts), "index out of range");
70 if constexpr (I == 0) return (ec);
71 else return std::get<I - 1>(values);
72 }
73
74 template<std::size_t I>
75 decltype(auto) get() const& noexcept
76 {
77 static_assert(I < 1 + sizeof...(Ts), "index out of range");
78 if constexpr (I == 0) return (ec);
79 else return std::get<I - 1>(values);
80 }
81
82 template<std::size_t I>
83 11622x decltype(auto) get() && noexcept
84 {
85 static_assert(I < 1 + sizeof...(Ts), "index out of range");
86 6267x if constexpr (I == 0) return std::move(ec);
87 5355x else return std::get<I - 1>(std::move(values));
88 }
89 /// @endcond
90 };
91
92 /// @cond
93 template<std::size_t I, class... Ts>
94 decltype(auto) get(io_result<Ts...>& r) noexcept
95 {
96 return r.template get<I>();
97 }
98
99 template<std::size_t I, class... Ts>
100 decltype(auto) get(io_result<Ts...> const& r) noexcept
101 {
102 return r.template get<I>();
103 }
104
105 template<std::size_t I, class... Ts>
106 decltype(auto) get(io_result<Ts...>&& r) noexcept
107 {
108 return std::move(r).template get<I>();
109 }
110 /// @endcond
111
112 } // namespace capy
113 } // namespace boost
114
115 // Tuple protocol for structured bindings
116 namespace std {
117
118 template<class... Ts>
119 struct tuple_size<boost::capy::io_result<Ts...>>
120 : std::integral_constant<std::size_t, 1 + sizeof...(Ts)> {};
121
122 template<class... Ts>
123 struct tuple_element<0, boost::capy::io_result<Ts...>>
124 {
125 using type = std::error_code;
126 };
127
128 template<std::size_t I, class... Ts>
129 struct tuple_element<I, boost::capy::io_result<Ts...>>
130 {
131 using type = std::tuple_element_t<I - 1, std::tuple<Ts...>>;
132 };
133
134 } // namespace std
135
136 #endif // BOOST_CAPY_IO_RESULT_HPP
137