ceph/src/boost/libs/fiber/examples/barrier.cpp

   1 #include <cstdlib>
   2 #include <functional>
   3 #include <iostream>
   4 #include <stdexcept>
   5
   6 #include <boost/assert.hpp>
   7
   8 #include <boost/fiber/all.hpp>
   9
  10 int value1 = 0;
  11 int value2 = 0;
  12
  13 inline
  14 void fn1( boost::fibers::barrier & b)
  15 {
  16     boost::fibers::fiber::id id = boost::this_fiber::get_id();
  17         std::cout << "fiber " << id << ": fn1 entered" << std::endl;
  18
  19         ++value1;
  20         std::cout << "fiber " << id << ": incremented value1: " << value1 << std::endl;
  21         boost::this_fiber::yield();
  22
  23         std::cout << "fiber " << id << ": waits for barrier" << std::endl;
  24         b.wait();
  25         std::cout << "fiber " << id << ": passed barrier" << std::endl;
  26
  27         ++value1;
  28         std::cout << "fiber " << id << ": incremented value1: " << value1 << std::endl;
  29         boost::this_fiber::yield();
  30
  31         ++value1;
  32         std::cout << "fiber " << id << ": incremented value1: " << value1 << std::endl;
  33         boost::this_fiber::yield();
  34
  35         ++value1;
  36         std::cout << "fiber " << id << ": incremented value1: " << value1 << std::endl;
  37         boost::this_fiber::yield();
  38
  39         std::cout << "fiber " << id << ": fn1 returns" << std::endl;
  40 }
  41
  42 inline
  43 void fn2( boost::fibers::barrier & b)
  44 {
  45     boost::fibers::fiber::id id = boost::this_fiber::get_id();
  46         std::cout << "fiber " << id << ": fn2 entered" << std::endl;
  47
  48         ++value2;
  49         std::cout << "fiber " << id << ": incremented value2: " << value2 << std::endl;
  50         boost::this_fiber::yield();
  51
  52         ++value2;
  53         std::cout << "fiber " << id << ": incremented value2: " << value2 << std::endl;
  54         boost::this_fiber::yield();
  55
  56         ++value2;
  57         std::cout << "fiber " << id << ": incremented value2: " << value2 << std::endl;
  58         boost::this_fiber::yield();
  59
  60         std::cout << "fiber " << id << ": waits for barrier" << std::endl;
  61         b.wait();
  62         std::cout << "fiber " << id << ": passed barrier" << std::endl;
  63
  64         ++value2;
  65         std::cout << "fiber " << id << ": incremented value2: " << value2 << std::endl;
  66         boost::this_fiber::yield();
  67
  68         std::cout << "fiber " << id << ": fn2 returns" << std::endl;
  69 }
  70
  71 int main()
  72 {
  73         try
  74         {
  75                 boost::fibers::barrier fb( 2);
  76
  77                 boost::fibers::fiber f1( & fn1, std::ref( fb) );
  78                 boost::fibers::fiber f2( & fn2, std::ref( fb) );
  79
  80         f1.join();
  81         f2.join();
  82
  83                 std::cout << "done." << std::endl;
  84
  85                 return EXIT_SUCCESS;
  86         }
  87         catch ( std::exception const& e)
  88         { std::cerr << "exception: " << e.what() << std::endl; }
  89         catch (...)
  90         { std::cerr << "unhandled exception" << std::endl; }
  91         return EXIT_FAILURE;
  92 }