libcxx/test/std/thread/thread.mutex/thread.lock/thread.lock.unique/thread.lock.unique.obs/owns_lock.pass.cpp

   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 owns_lock() const;
  14
  15 #include <cassert>
  16 #include <mutex>
  17
  18 #include "checking_mutex.h"
  19 #include "test_macros.h"
  20
  21 #if TEST_STD_VER >= 11
  22 static_assert(noexcept(std::declval<std::unique_lock<checking_mutex>&>().owns_lock()), "");
  23 #endif
  24
  25 int main(int, char**) {
  26   {
  27     checking_mutex mux;
  28     const std::unique_lock<checking_mutex> lock0; // Make sure `owns_lock()` is `const`
  29     assert(!lock0.owns_lock());
  30     std::unique_lock<checking_mutex> lock1(mux);
  31     assert(lock1.owns_lock());
  32     lock1.unlock();
  33     assert(!lock1.owns_lock());
  34   }
  35
  36   return 0;
  37 }