libstdc++-v3/testsuite/30_threads/semaphore/try_acquire.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-additional-options "-pthread" { target pthread } }
  20 // { dg-require-gthreads "" }
  21 // { dg-add-options libatomic }
  22
  23 #include <semaphore>
  24 #include <limits>
  25 #include <cstddef>
  26 #include <testsuite_hooks.h>
  27
  28 void test01()
  29 {
  30   std::counting_semaphore<10> s(3);
  31
  32   s.acquire();
  33   VERIFY( s.try_acquire() );
  34   VERIFY( s.try_acquire() );
  35   VERIFY( !s.try_acquire() );
  36   s.release();
  37   VERIFY( s.try_acquire() );
  38 }
  39
  40 void test02()
  41 {
  42   std::binary_semaphore s(1);
  43
  44   s.acquire();
  45   VERIFY( !s.try_acquire() );
  46   s.release();
  47   VERIFY( s.try_acquire() );
  48 }
  49
  50
  51 int main()
  52 {
  53   test01();
  54   test02();
  55 }