ceph/src/boost/libs/context/example/jump_mov.cpp

   1
   2 //          Copyright Oliver Kowalke 2016.
   3 // Distributed under the Boost Software License, Version 1.0.
   4 //    (See accompanying file LICENSE_1_0.txt or copy at
   5 //          http://www.boost.org/LICENSE_1_0.txt)
   6
   7 #include <cstdlib>
   8 #include <iostream>
   9
  10 #include <boost/context/continuation.hpp>
  11
  12 namespace ctx = boost::context;
  13
  14 class moveable {
  15 public:
  16     int     value;
  17
  18     moveable() :
  19         value( -1) {
  20         }
  21
  22     moveable( int v) :
  23         value( v) {
  24         }
  25
  26     moveable( moveable && other) {
  27         std::swap( value, other.value);
  28         }
  29
  30     moveable & operator=( moveable && other) {
  31         if ( this == & other) return * this;
  32         value = other.value;
  33         other.value = -1;
  34         return * this;
  35     }
  36
  37     moveable( moveable const& other) = delete;
  38     moveable & operator=( moveable const& other) = delete;
  39 };
  40
  41 int main() {
  42     ctx::continuation c;
  43     moveable data{ 1 };
  44     c = ctx::callcc( std::allocator_arg, ctx::fixedsize_stack{},
  45                      [&data](ctx::continuation && c){
  46                         std::cout << "entered first time: " << data.value << std::endl;
  47                         data = std::move( moveable{ 3 });
  48                         c = c.resume();
  49                         std::cout << "entered second time: " << data.value << std::endl;
  50                         data = std::move( moveable{});
  51                         return std::move( c);
  52                      });
  53     std::cout << "returned first time: " << data.value << std::endl;
  54     data.value = 5;
  55     c = c.resume();
  56     std::cout << "returned second time: " << data.value << std::endl;
  57     std::cout << "main: done" << std::endl;
  58     return EXIT_SUCCESS;
  59 }