1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
|
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// UNSUPPORTED: no-threads
// UNSUPPORTED: libcpp-has-no-experimental-stop_token
// UNSUPPORTED: c++03, c++11, c++14, c++17
// XFAIL: availability-synchronization_library-missing
// template<class C>
// explicit stop_callback(const stop_token& st, C&& cb)
// noexcept(is_nothrow_constructible_v<Callback, C>);
#include <atomic>
#include <cassert>
#include <chrono>
#include <stop_token>
#include <type_traits>
#include <utility>
#include <vector>
#include "make_test_thread.h"
#include "test_macros.h"
struct Cb {
void operator()() const;
};
// Constraints: Callback and C satisfy constructible_from<Callback, C>.
static_assert(std::is_constructible_v<std::stop_callback<void (*)()>, const std::stop_token&, void (*)()>);
static_assert(!std::is_constructible_v<std::stop_callback<void (*)()>, const std::stop_token&, void (*)(int)>);
static_assert(std::is_constructible_v<std::stop_callback<Cb>, const std::stop_token&, Cb&>);
static_assert(std::is_constructible_v<std::stop_callback<Cb&>, const std::stop_token&, Cb&>);
static_assert(!std::is_constructible_v<std::stop_callback<Cb>, const std::stop_token&, int>);
// explicit
template <class T>
void conversion_test(T);
template <class T, class... Args>
concept ImplicitlyConstructible = requires(Args&&... args) { conversion_test<T>({std::forward<Args>(args)...}); };
static_assert(ImplicitlyConstructible<int, int>);
static_assert(!ImplicitlyConstructible<std::stop_callback<Cb>, const std::stop_token&, Cb>);
// noexcept
template <bool NoExceptCtor>
struct CbNoExcept {
CbNoExcept(int) noexcept(NoExceptCtor);
void operator()() const;
};
static_assert(std::is_nothrow_constructible_v<std::stop_callback<CbNoExcept<true>>, const std::stop_token&, int>);
static_assert(!std::is_nothrow_constructible_v<std::stop_callback<CbNoExcept<false>>, const std::stop_token&, int>);
int main(int, char**) {
// was requested
{
std::stop_source ss;
const std::stop_token st = ss.get_token();
ss.request_stop();
bool called = false;
std::stop_callback sc(st, [&] { called = true; });
assert(called);
}
// was not requested
{
std::stop_source ss;
const std::stop_token st = ss.get_token();
bool called = false;
std::stop_callback sc(st, [&] { called = true; });
assert(!called);
ss.request_stop();
assert(called);
}
// token has no state
{
std::stop_token st;
bool called = false;
std::stop_callback sc(st, [&] { called = true; });
assert(!called);
}
// should not be called multiple times
{
std::stop_source ss;
const std::stop_token st = ss.get_token();
int calledTimes = 0;
std::stop_callback sc(st, [&] { ++calledTimes; });
std::vector<std::thread> threads;
for (auto i = 0; i < 10; ++i) {
threads.emplace_back(support::make_test_thread([&] { ss.request_stop(); }));
}
for (auto& thread : threads) {
thread.join();
}
assert(calledTimes == 1);
}
// adding more callbacks during invoking other callbacks
{
std::stop_source ss;
const std::stop_token st = ss.get_token();
std::atomic<bool> startedFlag = false;
std::atomic<bool> finishFlag = false;
std::stop_callback sc(st, [&] {
startedFlag = true;
startedFlag.notify_all();
finishFlag.wait(false);
});
auto thread = support::make_test_thread([&] { ss.request_stop(); });
startedFlag.wait(false);
// first callback is still running, adding another one;
bool secondCallbackCalled = false;
std::stop_callback sc2(st, [&] { secondCallbackCalled = true; });
finishFlag = true;
finishFlag.notify_all();
thread.join();
assert(secondCallbackCalled);
}
// adding callbacks on different threads
{
std::stop_source ss;
const std::stop_token st = ss.get_token();
std::vector<std::thread> threads;
std::atomic<int> callbackCalledTimes = 0;
std::atomic<bool> done = false;
for (auto i = 0; i < 10; ++i) {
threads.emplace_back(support::make_test_thread([&] {
std::stop_callback sc{st, [&] { callbackCalledTimes.fetch_add(1, std::memory_order_relaxed); }};
done.wait(false);
}));
}
using namespace std::chrono_literals;
std::this_thread::sleep_for(1ms);
ss.request_stop();
done = true;
done.notify_all();
for (auto& thread : threads) {
thread.join();
}
assert(callbackCalledTimes.load(std::memory_order_relaxed) == 10);
}
// correct overload
{
struct CBWithTracking {
bool& lvalueCalled;
bool& lvalueConstCalled;
bool& rvalueCalled;
bool& rvalueConstCalled;
void operator()() & { lvalueCalled = true; }
void operator()() const& { lvalueConstCalled = true; }
void operator()() && { rvalueCalled = true; }
void operator()() const&& { rvalueConstCalled = true; }
};
// RValue
{
bool lvalueCalled = false;
bool lvalueConstCalled = false;
bool rvalueCalled = false;
bool rvalueConstCalled = false;
std::stop_source ss;
const std::stop_token st = ss.get_token();
ss.request_stop();
std::stop_callback<CBWithTracking> sc(
st, CBWithTracking{lvalueCalled, lvalueConstCalled, rvalueCalled, rvalueConstCalled});
assert(rvalueCalled);
}
// RValue
{
bool lvalueCalled = false;
bool lvalueConstCalled = false;
bool rvalueCalled = false;
bool rvalueConstCalled = false;
std::stop_source ss;
const std::stop_token st = ss.get_token();
ss.request_stop();
std::stop_callback<const CBWithTracking> sc(
st, CBWithTracking{lvalueCalled, lvalueConstCalled, rvalueCalled, rvalueConstCalled});
assert(rvalueConstCalled);
}
// LValue
{
bool lvalueCalled = false;
bool lvalueConstCalled = false;
bool rvalueCalled = false;
bool rvalueConstCalled = false;
std::stop_source ss;
const std::stop_token st = ss.get_token();
ss.request_stop();
CBWithTracking cb{lvalueCalled, lvalueConstCalled, rvalueCalled, rvalueConstCalled};
std::stop_callback<CBWithTracking&> sc(st, cb);
assert(lvalueCalled);
}
// const LValue
{
bool lvalueCalled = false;
bool lvalueConstCalled = false;
bool rvalueCalled = false;
bool rvalueConstCalled = false;
std::stop_source ss;
const std::stop_token st = ss.get_token();
ss.request_stop();
CBWithTracking cb{lvalueCalled, lvalueConstCalled, rvalueCalled, rvalueConstCalled};
std::stop_callback<const CBWithTracking&> sc(st, cb);
assert(lvalueConstCalled);
}
}
return 0;
}
|
