drd/tests/shared_timed_mutex.cpp

   1 #include <thread>
   2 #include <iostream>
   3 #include <chrono>
   4 #include <shared_mutex>
   5 #include <mutex>
   6 #include <cassert>
   7 #include <condition_variable>
   8
   9 std::shared_timed_mutex test_mutex;
  10 std::mutex cv_mutex;
  11 std::condition_variable cv;
  12 int global;
  13 bool reads_done = false;
  14
  15 void f()
  16 {
  17     auto now=std::chrono::steady_clock::now();
  18     auto then = now + std::chrono::seconds(3);
  19     int i;
  20     for (i = 0; i < 3 && std::chrono::steady_clock::now() < then; ++i)
  21     {
  22        if (test_mutex.try_lock_until(then))
  23        {
  24           --global;
  25           test_mutex.unlock();
  26           break;
  27        }
  28     }
  29
  30     if (i == 3)
  31     {
  32         std::cerr << "Lock failed\n";
  33     }
  34 }
  35
  36 void g()
  37 {
  38     auto now=std::chrono::steady_clock::now();
  39     auto then = now + std::chrono::seconds(2);
  40     int i;
  41     for (i = 0; i < 3 && std::chrono::steady_clock::now() < then; ++i)
  42     {
  43         if (test_mutex.try_lock_shared_until(then))
  44         {
  45             test_mutex.unlock_shared();
  46             break;
  47         }
  48     }
  49     if (i == 3)
  50     {
  51         std::cerr << "Lock shared failed\n";
  52     }
  53     std::unique_lock<std::mutex> lock(cv_mutex);
  54     reads_done = true;
  55     cv.notify_all();
  56 }
  57
  58 int main()
  59 {
  60     global = 1;
  61     test_mutex.lock_shared();
  62     std::thread t1(f);
  63     std::thread t2(g);
  64     {
  65        std::unique_lock<std::mutex> lock(cv_mutex);
  66        while (!reads_done)
  67        {
  68           cv.wait(lock);
  69        }
  70     }
  71     test_mutex.unlock_shared();
  72     t1.join();
  73     t2.join();
  74     assert(global == 0);
  75 }
  76