libstdc++-v3/testsuite/30_threads/condition_variable/members/2.cc

   1 // { dg-do run }
   2 // { dg-options "-pthread"  }
   3 // { dg-require-effective-target c++11 }
   4 // { dg-require-effective-target pthread }
   5 // { dg-require-gthreads "" }
   6
   7 // Copyright (C) 2008-2020 Free Software Foundation, Inc.
   8 //
   9 // This file is part of the GNU ISO C++ Library.  This library is free
  10 // software; you can redistribute it and/or modify it under the
  11 // terms of the GNU General Public License as published by the
  12 // Free Software Foundation; either version 3, or (at your option)
  13 // any later version.
  14
  15 // This library is distributed in the hope that it will be useful,
  16 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 // GNU General Public License for more details.
  19
  20 // You should have received a copy of the GNU General Public License along
  21 // with this library; see the file COPYING3.  If not see
  22 // <http://www.gnu.org/licenses/>.
  23
  24 #include <chrono>
  25 #include <condition_variable>
  26 #include <system_error>
  27 #include <testsuite_hooks.h>
  28 #include <slow_clock.h>
  29
  30 template <typename ClockType>
  31 void test01()
  32 {
  33   try
  34     {
  35       std::chrono::microseconds ms(500);
  36       std::condition_variable c1;
  37       std::mutex m;
  38       std::unique_lock<std::mutex> l(m);
  39
  40       auto then = ClockType::now();
  41       std::cv_status result = c1.wait_until(l, then + ms);
  42       VERIFY( result == std::cv_status::timeout );
  43       VERIFY( (ClockType::now() - then) >= ms );
  44       VERIFY( l.owns_lock() );
  45     }
  46   catch (const std::system_error& e)
  47     {
  48       VERIFY( false );
  49     }
  50   catch (...)
  51     {
  52       VERIFY( false );
  53     }
  54 }
  55
  56 void test01_alternate_clock()
  57 {
  58   try
  59     {
  60       std::condition_variable c1;
  61       std::mutex m;
  62       std::unique_lock<std::mutex> l(m);
  63       auto const expire = slow_clock::now() + std::chrono::seconds(1);
  64
  65       while (slow_clock::now() < expire)
  66        {
  67          auto const result = c1.wait_until(l, expire);
  68
  69          // If wait_until returns before the timeout has expired when
  70          // measured against the supplied clock, then wait_until must
  71          // return no_timeout.
  72          if (slow_clock::now() < expire)
  73            VERIFY(result == std::cv_status::no_timeout);
  74
  75          // If wait_until returns timeout then the timeout must have
  76          // expired.
  77          if (result == std::cv_status::timeout)
  78            VERIFY(slow_clock::now() >= expire);
  79        }
  80     }
  81   catch (const std::system_error& e)
  82     {
  83       VERIFY( false );
  84     }
  85   catch (...)
  86     {
  87       VERIFY( false );
  88     }
  89 }
  90
  91 /* User defined clock that ticks in two-thousandths of a second
  92    forty-two minutes ahead of steady_clock. */
  93 struct user_defined_clock
  94 {
  95   typedef std::chrono::steady_clock::rep rep;
  96   typedef std::ratio<1, 2000> period;
  97   typedef std::chrono::duration<rep, period> duration;
  98   typedef std::chrono::time_point<user_defined_clock> time_point;
  99
 100   static constexpr bool is_steady = true;
 101
 102   static time_point now() noexcept
 103   {
 104     using namespace std::chrono;
 105     const auto steady_since_epoch = steady_clock::now().time_since_epoch();
 106     const auto user_since_epoch = duration_cast<duration>(steady_since_epoch);
 107     return time_point(user_since_epoch + minutes(42));
 108   }
 109 };
 110
 111 /*
 112 It's not possible for this test to automatically ensure that the
 113 system_clock test cases result in a wait on CLOCK_REALTIME and steady_clock
 114 test cases result in a wait on CLOCK_MONOTONIC. It's recommended to run the
 115 test under strace(1) and check whether the expected futex calls are made by
 116 glibc. See https://gcc.gnu.org/ml/libstdc++/2019-09/msg00022.html for
 117 instructions.
 118 */
 119
 120 int main()
 121 {
 122   test01<std::chrono::steady_clock>();
 123   test01<std::chrono::system_clock>();
 124   test01<user_defined_clock>();
 125   test01_alternate_clock();
 126 }