libstdc++-v3/testsuite/30_threads/latch/3.cc

   1 // Copyright (C) 2020-2024 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-do run { target c++20 } }
  19 // { dg-require-gthreads "" }
  20 // { dg-additional-options "-pthread" { target pthread } }
  21 // { dg-add-options libatomic }
  22
  23 #include <latch>
  24 #include <atomic>
  25 #include <thread>
  26 #include <testsuite_hooks.h>
  27
  28 void
  29 test01()
  30 {
  31   std::latch l(3);
  32
  33   VERIFY( !l.try_wait() );
  34
  35   auto fn = [&]
  36   {
  37     l.count_down();
  38   };
  39
  40   std::thread t0(fn);
  41   std::thread t1(fn);
  42
  43   l.arrive_and_wait();
  44   t0.join();
  45   t1.join();
  46
  47   VERIFY( l.try_wait() );
  48 }
  49
  50 void
  51 test02()
  52 {
  53   std::latch l(3);
  54   std::thread t([&]
  55     {
  56       l.count_down();
  57     });
  58
  59   l.arrive_and_wait(2);
  60   t.join();
  61   VERIFY( l.try_wait() );
  62 }
  63
  64 int main()
  65 {
  66   test01();
  67   test02();
  68   return 0;
  69 }