1 | //===----------------------------------------------------------------------===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | // |
9 | // UNSUPPORTED: no-threads |
10 | // UNSUPPORTED: c++03 |
11 | |
12 | // <future> |
13 | |
14 | // class shared_future<R> |
15 | |
16 | // template <class Clock, class Duration> |
17 | // future_status |
18 | // wait_until(const chrono::time_point<Clock, Duration>& abs_time) const; |
19 | |
20 | #include <atomic> |
21 | #include <cassert> |
22 | #include <chrono> |
23 | #include <future> |
24 | |
25 | #include "make_test_thread.h" |
26 | #include "test_macros.h" |
27 | |
28 | enum class WorkerThreadState { Uninitialized, AllowedToRun, Exiting }; |
29 | typedef std::chrono::milliseconds ms; |
30 | |
31 | std::atomic<WorkerThreadState> thread_state(WorkerThreadState::Uninitialized); |
32 | |
33 | void set_worker_thread_state(WorkerThreadState state) |
34 | { |
35 | thread_state.store(i: state, m: std::memory_order_relaxed); |
36 | } |
37 | |
38 | void wait_for_worker_thread_state(WorkerThreadState state) |
39 | { |
40 | while (thread_state.load(m: std::memory_order_relaxed) != state) |
41 | std::this_thread::yield(); |
42 | } |
43 | |
44 | void func1(std::promise<int> p) |
45 | { |
46 | wait_for_worker_thread_state(state: WorkerThreadState::AllowedToRun); |
47 | p.set_value(3); |
48 | set_worker_thread_state(WorkerThreadState::Exiting); |
49 | } |
50 | |
51 | int j = 0; |
52 | |
53 | void func3(std::promise<int&> p) |
54 | { |
55 | wait_for_worker_thread_state(state: WorkerThreadState::AllowedToRun); |
56 | j = 5; |
57 | p.set_value(j); |
58 | set_worker_thread_state(WorkerThreadState::Exiting); |
59 | } |
60 | |
61 | void func5(std::promise<void> p) |
62 | { |
63 | wait_for_worker_thread_state(state: WorkerThreadState::AllowedToRun); |
64 | p.set_value(); |
65 | set_worker_thread_state(WorkerThreadState::Exiting); |
66 | } |
67 | |
68 | int main(int, char**) |
69 | { |
70 | typedef std::chrono::high_resolution_clock Clock; |
71 | |
72 | { |
73 | typedef int T; |
74 | std::promise<T> p; |
75 | std::shared_future<T> f = p.get_future(); |
76 | support::make_test_thread(func1, std::move(p)).detach(); |
77 | assert(f.valid()); |
78 | assert(f.wait_until(Clock::now() + ms(10)) == std::future_status::timeout); |
79 | assert(f.valid()); |
80 | |
81 | // allow the worker thread to produce the result and wait until the worker is done |
82 | set_worker_thread_state(WorkerThreadState::AllowedToRun); |
83 | wait_for_worker_thread_state(state: WorkerThreadState::Exiting); |
84 | |
85 | assert(f.wait_until(Clock::now() + ms(10)) == std::future_status::ready); |
86 | assert(f.valid()); |
87 | f.wait(); |
88 | assert(f.valid()); |
89 | } |
90 | { |
91 | typedef int& T; |
92 | std::promise<T> p; |
93 | std::shared_future<T> f = p.get_future(); |
94 | support::make_test_thread(func3, std::move(p)).detach(); |
95 | assert(f.valid()); |
96 | assert(f.wait_until(Clock::now() + ms(10)) == std::future_status::timeout); |
97 | assert(f.valid()); |
98 | |
99 | // allow the worker thread to produce the result and wait until the worker is done |
100 | set_worker_thread_state(WorkerThreadState::AllowedToRun); |
101 | wait_for_worker_thread_state(state: WorkerThreadState::Exiting); |
102 | |
103 | assert(f.wait_until(Clock::now() + ms(10)) == std::future_status::ready); |
104 | assert(f.valid()); |
105 | f.wait(); |
106 | assert(f.valid()); |
107 | } |
108 | { |
109 | typedef void T; |
110 | std::promise<T> p; |
111 | std::shared_future<T> f = p.get_future(); |
112 | support::make_test_thread(func5, std::move(p)).detach(); |
113 | assert(f.valid()); |
114 | assert(f.wait_until(Clock::now() + ms(10)) == std::future_status::timeout); |
115 | assert(f.valid()); |
116 | |
117 | // allow the worker thread to produce the result and wait until the worker is done |
118 | set_worker_thread_state(WorkerThreadState::AllowedToRun); |
119 | wait_for_worker_thread_state(state: WorkerThreadState::Exiting); |
120 | |
121 | assert(f.wait_until(Clock::now() + ms(10)) == std::future_status::ready); |
122 | assert(f.valid()); |
123 | f.wait(); |
124 | assert(f.valid()); |
125 | } |
126 | |
127 | return 0; |
128 | } |
129 | |