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, c++11
11 // ALLOW_RETRIES: 2
12 
13 // dylib support for shared_mutex was added in macosx10.12
14 // XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11}}
15 
16 // <shared_mutex>
17 
18 // template <class Mutex> class shared_lock;
19 
20 // void lock();
21 
22 #include <shared_mutex>
23 #include <thread>
24 #include <vector>
25 #include <cstdlib>
26 #include <cassert>
27 
28 #include "make_test_thread.h"
29 #include "test_macros.h"
30 
31 std::shared_timed_mutex m;
32 
33 typedef std::chrono::system_clock Clock;
34 typedef Clock::time_point time_point;
35 typedef Clock::duration duration;
36 typedef std::chrono::milliseconds ms;
37 typedef std::chrono::nanoseconds ns;
38 
39 ms WaitTime = ms(250);
40 
41 // Thread sanitizer causes more overhead and will sometimes cause this test
42 // to fail. To prevent this we give Thread sanitizer more time to complete the
43 // test.
44 #if !defined(TEST_HAS_SANITIZERS)
45 ms Tolerance = ms(25);
46 #else
47 ms Tolerance = ms(25 * 5);
48 #endif
49 
50 
f()51 void f()
52 {
53     std::shared_lock<std::shared_timed_mutex> lk(m, std::defer_lock);
54     time_point t0 = Clock::now();
55     lk.lock();
56     time_point t1 = Clock::now();
57     assert(lk.owns_lock() == true);
58     ns d = t1 - t0 - WaitTime;
59     assert(d < Tolerance);  // within tolerance
60 #ifndef TEST_HAS_NO_EXCEPTIONS
61     try
62     {
63         lk.lock();
64         assert(false);
65     }
66     catch (std::system_error& e)
67     {
68         assert(e.code().value() == EDEADLK);
69     }
70 #endif
71     lk.unlock();
72     lk.release();
73 #ifndef TEST_HAS_NO_EXCEPTIONS
74     try
75     {
76         lk.lock();
77         assert(false);
78     }
79     catch (std::system_error& e)
80     {
81         assert(e.code().value() == EPERM);
82     }
83 #endif
84 }
85 
main(int,char **)86 int main(int, char**)
87 {
88     m.lock();
89     std::vector<std::thread> v;
90     for (int i = 0; i < 5; ++i)
91         v.push_back(support::make_test_thread(f));
92     std::this_thread::sleep_for(WaitTime);
93     m.unlock();
94     for (auto& t : v)
95         t.join();
96 
97   return 0;
98 }
99