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// <mutex>
10
11// template <class Mutex> class unique_lock;
12
13// bool try_lock();
14
15#include <cassert>
16#include <mutex>
17#include <system_error>
18
19#include "test_macros.h"
20#include "checking_mutex.h"
21
22int main(int, char**) {
23 checking_mutex mux;
24
25 std::unique_lock<checking_mutex> lock(mux, std::defer_lock_t());
26 assert(lock.try_lock());
27 assert(mux.current_state == checking_mutex::locked_via_try_lock);
28 assert(lock.owns_lock());
29
30#ifndef TEST_HAS_NO_EXCEPTIONS
31 try {
32 mux.last_try = checking_mutex::none;
33 TEST_IGNORE_NODISCARD lock.try_lock();
34 assert(false);
35 } catch (std::system_error& e) {
36 assert(mux.last_try == checking_mutex::none);
37 assert(e.code() == std::errc::resource_deadlock_would_occur);
38 }
39#endif
40
41 lock.unlock();
42 mux.reject = true;
43
44 assert(!lock.try_lock());
45 assert(mux.last_try == checking_mutex::locked_via_try_lock);
46
47 assert(!lock.owns_lock());
48 lock.release();
49
50#ifndef TEST_HAS_NO_EXCEPTIONS
51 try {
52 mux.last_try = checking_mutex::none;
53 (void)lock.try_lock();
54 assert(false);
55 } catch (std::system_error& e) {
56 assert(mux.last_try == checking_mutex::none);
57 assert(e.code() == std::errc::operation_not_permitted);
58 }
59#endif
60
61 return 0;
62}
63

source code of libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.locking/try_lock.pass.cpp