text: 
  //          Copyright Oliver Kowalke 2009.
  // Distributed under the Boost Software License, Version 1.0.
  //    (See accompanying file LICENSE_1_0.txt or copy at
  //          http://www.boost.org/LICENSE_1_0.txt)
  
  #ifndef BOOST_COROUTINES_DETAIL_PUSH_COROUTINE_OBJECT_H
  #define BOOST_COROUTINES_DETAIL_PUSH_COROUTINE_OBJECT_H
  
  #include <boost/assert.hpp>
  #include <boost/config.hpp>
  #include <boost/cstdint.hpp>
  #include <boost/exception_ptr.hpp>
  #include <boost/move/move.hpp>
  
  #include <boost/coroutine/detail/config.hpp>
  #include <boost/coroutine/detail/coroutine_context.hpp>
  #include <boost/coroutine/detail/flags.hpp>
  #include <boost/coroutine/detail/preallocated.hpp>
  #include <boost/coroutine/detail/push_coroutine_impl.hpp>
  #include <boost/coroutine/detail/trampoline_push.hpp>
  #include <boost/coroutine/exceptions.hpp>
  #include <boost/coroutine/flags.hpp>
  #include <boost/coroutine/stack_context.hpp>
  
  #ifdef BOOST_HAS_ABI_HEADERS
  #  include BOOST_ABI_PREFIX
  #endif
  
  #if defined(BOOST_MSVC)
  # pragma warning(push)
  # pragma warning(disable:4355)
  #endif
  
  namespace boost {
  namespace coroutines {
  namespace detail {
  
  struct push_coroutine_context
  {
      coroutine_context   caller;
      coroutine_context   callee;
  
      template< typename Coro >
      push_coroutine_context( preallocated const& palloc, Coro *) :
          caller(),
          callee( trampoline_push< Coro >, palloc)
      {}
  };
  
  struct push_coroutine_context_void
  {
      coroutine_context   caller;
      coroutine_context   callee;
  
      template< typename Coro >
      push_coroutine_context_void( preallocated const& palloc, Coro *) :
          caller(),
          callee( trampoline_push_void< Coro >, palloc)
      {}
  };
  
  template< typename PullCoro, typename R, typename Fn, typename StackAllocator >
  class push_coroutine_object : private push_coroutine_context,
                                public push_coroutine_impl< R >
  {
  private:
      typedef push_coroutine_context                                      ctx_t;
      typedef push_coroutine_impl< R >                                    base_t;
      typedef push_coroutine_object< PullCoro, R, Fn, StackAllocator >    obj_t;
  
      Fn                  fn_;
      stack_context       stack_ctx_;
      StackAllocator      stack_alloc_;
  
      static void deallocate_( obj_t * obj)
      {
          stack_context stack_ctx( obj->stack_ctx_);
          StackAllocator stack_alloc( obj->stack_alloc_);
          obj->unwind_stack();
          obj->~obj_t();
          stack_alloc.deallocate( stack_ctx);
      }
  
  public:
  #ifdef BOOST_NO_CXX11_RVALUE_REFERENCES
      push_coroutine_object( Fn fn, attributes const& attrs,
                             preallocated const& palloc,
                             StackAllocator const& stack_alloc) BOOST_NOEXCEPT :
          ctx_t( palloc, this),
          base_t( & this->caller,
                  & this->callee,
                  stack_unwind == attrs.do_unwind),
          fn_( fn),
          stack_ctx_( palloc.sctx),
          stack_alloc_( stack_alloc)
      {}
  #endif
  
      push_coroutine_object( BOOST_RV_REF( Fn) fn, attributes const& attrs,
                             preallocated const& palloc,
                             StackAllocator const& stack_alloc) BOOST_NOEXCEPT :
          ctx_t( palloc, this),
          base_t( & this->caller,
                  & this->callee,
                  stack_unwind == attrs.do_unwind),
  #ifdef BOOST_NO_CXX11_RVALUE_REFERENCES
          fn_( fn),
  #else
          fn_( boost::forward< Fn >( fn) ),
  #endif
          stack_ctx_( palloc.sctx),
          stack_alloc_( stack_alloc)
      {}
  
      void run( R * result)
      {
          BOOST_ASSERT( ! base_t::unwind_requested() );
  
          base_t::flags_ |= flag_started;
          base_t::flags_ |= flag_running;
  
          // create push_coroutine
          typename PullCoro::synth_type b( & this->callee, & this->caller, false, result);
          PullCoro pull_coro( synthesized_t::syntesized, b);
          try
          { fn_( pull_coro); }
          catch ( forced_unwind const&)
          {}
          catch (...)
          { base_t::except_ = current_exception(); }
  
          base_t::flags_ |= flag_complete;
          base_t::flags_ &= ~flag_running;
          typename base_t::param_type to;
          this->callee.jump(
              this->caller,
              & to);
          BOOST_ASSERT_MSG( false, "pull_coroutine is complete");
      }
  
      void destroy()
      { deallocate_( this); }
  };
  
  template< typename PullCoro, typename R, typename Fn, typename StackAllocator >
  class push_coroutine_object< PullCoro, R &, Fn, StackAllocator > : private push_coroutine_context,
                                                                     public push_coroutine_impl< R & >
  {
  private:
      typedef push_coroutine_context                                          ctx_t;
      typedef push_coroutine_impl< R & >                                      base_t;
      typedef push_coroutine_object< PullCoro, R &, Fn, StackAllocator >      obj_t;
  
      Fn                  fn_;
      stack_context       stack_ctx_;
      StackAllocator      stack_alloc_;
  
      static void deallocate_( obj_t * obj)
      {
          stack_context stack_ctx( obj->stack_ctx_);
          StackAllocator stack_alloc( obj->stack_alloc_);
          obj->unwind_stack();
          obj->~obj_t();
          stack_alloc.deallocate( stack_ctx);
      }
  
  public:
  #ifdef BOOST_NO_CXX11_RVALUE_REFERENCES
      push_coroutine_object( Fn fn, attributes const& attrs,
                             preallocated const& palloc,
                             StackAllocator const& stack_alloc) BOOST_NOEXCEPT :
          ctx_t( palloc, this),
          base_t( & this->caller,
                  & this->callee,
                  stack_unwind == attrs.do_unwind),
          fn_( fn),
          stack_ctx_( palloc.sctx),
          stack_alloc_( stack_alloc)
      {}
  #endif
  
      push_coroutine_object( BOOST_RV_REF( Fn) fn, attributes const& attrs,
                             preallocated const& palloc,
                             StackAllocator const& stack_alloc) BOOST_NOEXCEPT :
          ctx_t( palloc, this),
          base_t( & this->caller,
                  & this->callee,
                  stack_unwind == attrs.do_unwind),
  #ifdef BOOST_NO_CXX11_RVALUE_REFERENCES
          fn_( fn),
  #else
          fn_( boost::forward< Fn >( fn) ),
  #endif
          stack_ctx_( palloc.sctx),
          stack_alloc_( stack_alloc)
      {}
  
      void run( R * result)
      {
          BOOST_ASSERT( ! base_t::unwind_requested() );
  
          base_t::flags_ |= flag_started;
          base_t::flags_ |= flag_running;
  
          // create push_coroutine
          typename PullCoro::synth_type b( & this->callee, & this->caller, false, result);
          PullCoro push_coro( synthesized_t::syntesized, b);
          try
          { fn_( push_coro); }
          catch ( forced_unwind const&)
          {}
          catch (...)
          { base_t::except_ = current_exception(); }
  
          base_t::flags_ |= flag_complete;
          base_t::flags_ &= ~flag_running;
          typename base_t::param_type to;
          this->callee.jump(
              this->caller,
              & to);
          BOOST_ASSERT_MSG( false, "pull_coroutine is complete");
      }
  
      void destroy()
      { deallocate_( this); }
  };
  
  template< typename PullCoro, typename Fn, typename StackAllocator >
  class push_coroutine_object< PullCoro, void, Fn, StackAllocator > : private push_coroutine_context_void,
                                                                      public push_coroutine_impl< void >
  {
  private:
      typedef push_coroutine_context_void                                     ctx_t;
      typedef push_coroutine_impl< void >                                     base_t;
      typedef push_coroutine_object< PullCoro, void, Fn, StackAllocator >     obj_t;
  
      Fn                  fn_;
      stack_context       stack_ctx_;
      StackAllocator      stack_alloc_;
  
      static void deallocate_( obj_t * obj)
      {
          stack_context stack_ctx( obj->stack_ctx_);
          StackAllocator stack_alloc( obj->stack_alloc_);
          obj->unwind_stack();
          obj->~obj_t();
          stack_alloc.deallocate( stack_ctx);
      }
  
  public:
  #ifdef BOOST_NO_CXX11_RVALUE_REFERENCES
      push_coroutine_object( Fn fn, attributes const& attrs,
                             preallocated const& palloc,
                             StackAllocator const& stack_alloc) BOOST_NOEXCEPT :
          ctx_t( palloc, this),
          base_t( & this->caller,
                  & this->callee,
                  stack_unwind == attrs.do_unwind),
          fn_( fn),
          stack_ctx_( palloc.sctx),
          stack_alloc_( stack_alloc)
      {}
  #endif
  
      push_coroutine_object( BOOST_RV_REF( Fn) fn, attributes const& attrs,
                             preallocated const& palloc,
                             StackAllocator const& stack_alloc) BOOST_NOEXCEPT :
          ctx_t( palloc, this),
          base_t( & this->caller,
                  & this->callee,
                  stack_unwind == attrs.do_unwind),
  #ifdef BOOST_NO_CXX11_RVALUE_REFERENCES
          fn_( fn),
  #else
          fn_( boost::forward< Fn >( fn) ),
  #endif
          stack_ctx_( palloc.sctx),
          stack_alloc_( stack_alloc)
      {}
  
      void run()
      {
          BOOST_ASSERT( ! base_t::unwind_requested() );
  
          base_t::flags_ |= flag_started;
          base_t::flags_ |= flag_running;
  
          // create push_coroutine
          typename PullCoro::synth_type b( & this->callee, & this->caller, false);
          PullCoro push_coro( synthesized_t::syntesized, b);
          try
          { fn_( push_coro); }
          catch ( forced_unwind const&)
          {}
          catch (...)
          { base_t::except_ = current_exception(); }
  
          base_t::flags_ |= flag_complete;
          base_t::flags_ &= ~flag_running;
          typename base_t::param_type to;
          this->callee.jump(
              this->caller,
              & to);
          BOOST_ASSERT_MSG( false, "pull_coroutine is complete");
      }
  
      void destroy()
      { deallocate_( this); }
  };
  
  }}}
  
  #if defined(BOOST_MSVC)
  # pragma warning(pop)
  #endif
  
  #ifdef BOOST_HAS_ABI_HEADERS
  #  include BOOST_ABI_SUFFIX
  #endif
  
  #endif // BOOST_COROUTINES_DETAIL_PUSH_COROUTINE_OBJECT_H
  