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

   1 // Copyright (C) 2012-2013 Vicente Botet
   2 //
   3 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #include <boost/config.hpp>
   7 #if ! defined  BOOST_NO_CXX11_DECLTYPE
   8 #define BOOST_RESULT_OF_USE_DECLTYPE
   9 #endif
  10
  11 #define BOOST_THREAD_VERSION 4
  12 //#define BOOST_THREAD_USES_LOG
  13 #define BOOST_THREAD_USES_LOG_THREAD_ID
  14
  15 #include <boost/thread/detail/log.hpp>
  16 #include <boost/thread/future.hpp>
  17 #include <boost/assert.hpp>
  18 #include <string>
  19 #include <iostream>
  20
  21 #if defined BOOST_THREAD_PROVIDES_FUTURE_UNWRAP
  22
  23 #ifdef BOOST_MSVC
  24 #pragma warning(disable: 4127) // conditional expression is constant
  25 #endif
  26
  27 int p1()
  28 {
  29   BOOST_THREAD_LOG << "P1" << BOOST_THREAD_END_LOG;
  30   return 123;
  31 }
  32
  33 boost::future<int> p2()
  34 {
  35   BOOST_THREAD_LOG << "<P2" << BOOST_THREAD_END_LOG;
  36   boost::future<int> f1 = boost::async(boost::launch::async, &p1);
  37   BOOST_THREAD_LOG << "P2>" << BOOST_THREAD_END_LOG;
  38   return boost::move(f1);
  39 }
  40
  41 int main()
  42 {
  43   const int number_of_tests = 100;
  44   BOOST_THREAD_LOG << "<MAIN" << BOOST_THREAD_END_LOG;
  45   for (int i=0; i< number_of_tests; i++)
  46   try
  47   {
  48
  49 #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
  50     {
  51       boost::future<int> inner_future = boost::async(boost::launch::async, &p2).unwrap();
  52       inner_future.wait();
  53       int ii = inner_future.get();
  54       BOOST_THREAD_LOG << "ii= "<< ii << "" << BOOST_THREAD_END_LOG;
  55     }
  56 #endif
  57     {
  58       boost::future<boost::future<int> > outer_future = boost::async(boost::launch::async, &p2);
  59       boost::future<int> inner_future = outer_future.unwrap();
  60       inner_future.wait();
  61       int ii = inner_future.get();
  62       BOOST_THREAD_LOG << "ii= "<< ii << "" << BOOST_THREAD_END_LOG;
  63     }
  64     {
  65       boost::future<boost::future<int> > outer_future = boost::async(boost::launch::async, &p2);
  66       boost::future<int> inner_future = outer_future.unwrap();
  67       int ii = inner_future.get();
  68       BOOST_THREAD_LOG << "ii= "<< ii << "" << BOOST_THREAD_END_LOG;
  69     }
  70   }
  71   catch (std::exception& ex)
  72   {
  73     std::cout << "ERRORRRRR "<<ex.what() << "" << std::endl;
  74     BOOST_THREAD_LOG << "ERRORRRRR "<<ex.what() << "" << BOOST_THREAD_END_LOG;
  75     return 1;
  76   }
  77   catch (...)
  78   {
  79     std::cout << " ERRORRRRR exception thrown" << std::endl;
  80     BOOST_THREAD_LOG << " ERRORRRRR exception thrown" << BOOST_THREAD_END_LOG;
  81     return 2;
  82   }
  83   BOOST_THREAD_LOG << "MAIN>" << BOOST_THREAD_END_LOG;
  84   return 0;
  85 }
  86 #else
  87
  88 int main()
  89 {
  90   return 0;
  91 }
  92 #endif