drd/tests/condvar.cpp

   1 /* See also https://bugs.kde.org/show_bug.cgi?id=445504 */
   2
   3 #include <condition_variable>
   4 #include <future>
   5 #include <iostream>
   6 #include <mutex>
   7 #include <thread>
   8 #include <vector>
   9
  10 using lock_guard = std::lock_guard<std::mutex>;
  11 using unique_lock = std::unique_lock<std::mutex>;
  12
  13 struct state {
  14   std::mutex m;
  15   std::vector<int> v;
  16   std::condition_variable cv;
  17
  18   state() {
  19     // Call pthread_cond_init() explicitly to let DRD know about 'cv'.
  20     pthread_cond_init(cv.native_handle(), NULL);
  21   }
  22 };
  23
  24 void other_thread(state *sp) {
  25   state &s = *sp;
  26   std::cerr << "Other thread: waiting for notify\n";
  27   unique_lock l{s.m};
  28   while (true) {
  29     if (s.cv.wait_for(l, std::chrono::seconds(3)) !=
  30         std::cv_status::timeout) {
  31       std::cerr << "Other thread: notified\n";
  32       break;
  33     }
  34   }
  35   return;
  36 }
  37
  38
  39 int main() {
  40   state s;
  41   auto future = std::async(std::launch::async, other_thread, &s);
  42
  43   if (future.wait_for(std::chrono::seconds(1)) != std::future_status::timeout) {
  44     std::cerr << "Main: other thread returned too early!\n";
  45     return 2;
  46   }
  47
  48   {
  49     std::lock_guard<std::mutex> g{s.m};
  50     s.v.push_back(1);
  51     s.v.push_back(2);
  52     s.cv.notify_all();
  53   }
  54   return 0;
  55 }