ceph/src/boost/libs/thread/test/sync/mutual_exclusion/null_mutex/try_lock_pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is dual licensed under the MIT and the University of Illinois Open
   6 // Source Licenses. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 // Copyright (C) 2011 Vicente J. Botet Escriba
  11 //
  12 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
  13 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  14
  15 // <boost/thread/null_mutex.hpp>
  16
  17 // class null_mutex;
  18
  19 // bool try_lock();
  20
  21 #include <boost/thread/null_mutex.hpp>
  22 #include <boost/thread/thread.hpp>
  23 #include <boost/detail/lightweight_test.hpp>
  24
  25
  26
  27 boost::null_mutex m;
  28
  29 #if defined BOOST_THREAD_USES_CHRONO
  30 typedef boost::chrono::system_clock Clock;
  31 typedef Clock::time_point time_point;
  32 typedef Clock::duration duration;
  33 typedef boost::chrono::milliseconds ms;
  34 typedef boost::chrono::nanoseconds ns;
  35 #else
  36 #endif
  37
  38 void f()
  39 {
  40 #if defined BOOST_THREAD_USES_CHRONO
  41   time_point t0 = Clock::now();
  42   BOOST_TEST(m.try_lock());
  43   time_point t1 = Clock::now();
  44   BOOST_TEST(m.try_lock());
  45   m.unlock();
  46   m.unlock();
  47   ns d = t1 - t0;
  48   // This test is spurious as it depends on the time the thread system switches the threads
  49   BOOST_TEST(d < ns(50000000)); // within 50ms
  50 #else
  51   BOOST_TEST(m.try_lock());
  52   BOOST_TEST(m.try_lock());
  53   m.unlock();
  54   m.unlock();
  55 #endif
  56 }
  57
  58 int main()
  59 {
  60   m.lock();
  61   boost::thread t(f);
  62   m.unlock();
  63   t.join();
  64
  65   return boost::report_errors();
  66 }
  67
  68