libstdc++-v3/testsuite/29_atomics/atomic_ref/wait_notify.cc

   1 // { dg-options "-std=gnu++2a -pthread" }
   2 // { dg-do run { target c++2a } }
   3 // { dg-require-effective-target pthread }
   4 // { dg-require-gthreads "" }
   5
   6 // Copyright (C) 2020 Free Software Foundation, Inc.
   7 //
   8 // This file is part of the GNU ISO C++ Library.  This library is free
   9 // software; you can redistribute it and/or modify it under the
  10 // terms of the GNU General Public License as published by the
  11 // Free Software Foundation; either version 3, or (at your option)
  12 // any later version.
  13
  14 // This library is distributed in the hope that it will be useful,
  15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 // GNU General Public License for more details.
  18
  19 // You should have received a copy of the GNU General Public License along
  20 // with this library; see the file COPYING3.  If not see
  21 // <http://www.gnu.org/licenses/>.
  22
  23 #include <atomic>
  24 #include <thread>
  25 #include <mutex>
  26 #include <condition_variable>
  27 #include <chrono>
  28 #include <type_traits>
  29
  30 #include <testsuite_hooks.h>
  31
  32 template<typename Tp>
  33 Tp check_wait_notify(Tp val1, Tp val2)
  34 {
  35   using namespace std::literals::chrono_literals;
  36
  37   std::mutex m;
  38   std::condition_variable cv;
  39
  40   Tp aa = val1;
  41   std::atomic_ref<Tp> a(aa);
  42   std::thread t([&]
  43                 {
  44                   cv.notify_one();
  45                   a.wait(val1);
  46                   if (a.load() != val2)
  47                     a = val1;
  48                 });
  49   std::unique_lock<std::mutex> l(m);
  50   cv.wait(l);
  51   std::this_thread::sleep_for(100ms);
  52   a.store(val2);
  53   a.notify_one();
  54   t.join();
  55   return a.load();
  56 }
  57
  58 template<typename Tp,
  59          bool = std::is_integral_v<Tp>
  60          || std::is_floating_point_v<Tp>>
  61 struct check;
  62
  63 template<typename Tp>
  64 struct check<Tp, true>
  65 {
  66   check()
  67   {
  68     Tp a = 0;
  69     Tp b = 42;
  70     VERIFY(check_wait_notify(a, b) == b);
  71   }
  72 };
  73
  74 template<typename Tp>
  75 struct check<Tp, false>
  76 {
  77   check(Tp b)
  78   {
  79     Tp a;
  80     VERIFY(check_wait_notify(a, b) == b);
  81   }
  82 };
  83
  84 int
  85 main ()
  86 {
  87   check<long>();
  88   check<double>();
  89   return 0;
  90 }