ceph/src/boost/libs/thread/example/with_lock_guard.cpp

   1 // (C) Copyright 2013 Ruslan Baratov
   2 // Copyright (C) 2014 Vicente Botet
   3 //
   4 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   5 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6
   7 //  See www.boost.org/libs/thread for documentation.
   8
   9 #define BOOST_THREAD_VERSION 4
  10
  11 #include <iostream> // std::cout
  12 #include <boost/thread/scoped_thread.hpp>
  13 #include <boost/thread/with_lock_guard.hpp>
  14
  15 boost::mutex m; // protection for 'x' and 'std::cout'
  16 int x;
  17
  18 #if defined(BOOST_NO_CXX11_LAMBDAS)  || (defined BOOST_MSVC && _MSC_VER < 1700)
  19 void print_x() {
  20   ++x;
  21   std::cout << "x = " << x << std::endl;
  22 }
  23
  24 void job() {
  25   for (int i = 0; i < 10; ++i) {
  26     boost::with_lock_guard(m, print_x);
  27     boost::this_thread::sleep_for(boost::chrono::milliseconds(100));
  28   }
  29 }
  30 #else
  31 void job() {
  32   for (int i = 0; i < 10; ++i) {
  33     boost::with_lock_guard(
  34         m,
  35         []() {
  36           ++x;
  37           std::cout << "x = " << x << std::endl;
  38         }
  39     );
  40     boost::this_thread::sleep_for(boost::chrono::milliseconds(100));
  41   }
  42 }
  43 #endif
  44
  45 int main() {
  46 #if defined(BOOST_NO_CXX11_LAMBDAS)  || (defined BOOST_MSVC && _MSC_VER < 1700)
  47   std::cout << "(no lambdas)" << std::endl;
  48 #endif
  49   boost::scoped_thread<> thread_1((boost::thread(job)));
  50   boost::scoped_thread<> thread_2((boost::thread(job)));
  51   boost::scoped_thread<> thread_3((boost::thread(job)));
  52   return 0;
  53 }