state_machine.hpp

support vector clustering for vc++

#ifndef BOOST_STATECHART_STATE_MACHINE_HPP_INCLUDED
#define BOOST_STATECHART_STATE_MACHINE_HPP_INCLUDED
//////////////////////////////////////////////////////////////////////////////
// Copyright 2002-2006 Andreas Huber Doenni
// Distributed under the Boost Software License, Version 1.0. (See accompany-
// ing file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//////////////////////////////////////////////////////////////////////////////



#include <boost/statechart/event.hpp>
#include <boost/statechart/null_exception_translator.hpp>
#include <boost/statechart/result.hpp>

#include <boost/statechart/detail/rtti_policy.hpp>
#include <boost/statechart/detail/state_base.hpp>
#include <boost/statechart/detail/leaf_state.hpp>
#include <boost/statechart/detail/node_state.hpp>
#include <boost/statechart/detail/constructor.hpp>
#include <boost/statechart/detail/avoid_unused_warning.hpp>

#include <boost/mpl/list.hpp>
#include <boost/mpl/clear.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/at.hpp>
#include <boost/mpl/integral_c.hpp>
#include <boost/mpl/minus.hpp>
#include <boost/mpl/equal_to.hpp>

#include <boost/intrusive_ptr.hpp>
#include <boost/type_traits/is_pointer.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/noncopyable.hpp>
#include <boost/assert.hpp>
#include <boost/static_assert.hpp>
#include <boost/cast.hpp> // boost::polymorphic_downcast
// BOOST_NO_EXCEPTIONS, BOOST_MSVC, BOOST_MSVC_STD_ITERATOR
#include <boost/config.hpp>

#include <boost/detail/allocator_utilities.hpp>

#ifdef BOOST_MSVC
#  pragma warning( push )
#  pragma warning( disable: 4702 ) // unreachable code (in release mode only)
#endif

#include <map>

#ifdef BOOST_MSVC
#  pragma warning( pop )
#endif

#include <memory>   // std::allocator
#include <typeinfo> // std::bad_cast
#include <functional> // std::less
#include <iterator>



#ifdef BOOST_MSVC
// We permanently turn off the following level 4 warnings because users will
// have to do so themselves anyway if we turn them back on
#  pragma warning( disable: 4511 ) // copy constructor could not be generated
#  pragma warning( disable: 4512 ) // assignment op could not be generated
#endif



namespace boost
{
namespace statechart
{
namespace detail
{



//////////////////////////////////////////////////////////////////////////////
template< class StateBaseType, class EventBaseType, class IdType >
class send_function
{
  public:
    //////////////////////////////////////////////////////////////////////////
    send_function(
      StateBaseType & toState,
      const EventBaseType & evt,
      IdType eventType
    ) :
      toState_( toState ), evt_( evt ), eventType_( eventType )
    {
    }

    result operator()()
    {
      return detail::result_utility::make_result(
        toState_.react_impl( evt_, eventType_ ) );
    }

  private:
    //////////////////////////////////////////////////////////////////////////
    StateBaseType & toState_;
    const EventBaseType & evt_;
    IdType eventType_;
};


//////////////////////////////////////////////////////////////////////////////
struct state_cast_impl_pointer_target
{
  public:
    //////////////////////////////////////////////////////////////////////////
    template< class StateBaseType >
    static const StateBaseType * deref_if_necessary(
      const StateBaseType * pState )
    {
      return pState;
    }

    template< class Target, class IdType >
    static IdType type_id()
    {
      Target p = 0;
      return type_id_impl< IdType >( p );
    }

    static bool found( const void * pFound )
    {
      return pFound != 0;
    }

    template< class Target >
    static Target not_found()
    {
      return 0;
    }

  private:
    //////////////////////////////////////////////////////////////////////////
    template< class IdType, class Type >
    static IdType type_id_impl( const Type * )
    {
      return Type::static_type();
    }
};

struct state_cast_impl_reference_target
{
  template< class StateBaseType >
  static const StateBaseType & deref_if_necessary(
    const StateBaseType * pState )
  {
    return *pState;
  }

  template< class Target, class IdType >
  static IdType type_id()
  {
    return remove_reference< Target >::type::static_type();
  }

  template< class Dummy >
  static bool found( const Dummy & )
  {
    return true;
  }

  template< class Target >
  static Target not_found()
  {
    throw std::bad_cast();
  }
};

template< class Target >
struct state_cast_impl : public mpl::if_<
  is_pointer< Target >,
  state_cast_impl_pointer_target,
  state_cast_impl_reference_target
>::type {};


//////////////////////////////////////////////////////////////////////////////
template< class RttiPolicy >
class history_key
{
  public:
    //////////////////////////////////////////////////////////////////////////
    template< class HistorizedState >
    static history_key make_history_key()
    {
      return history_key(
        HistorizedState::context_type::static_type(),
        HistorizedState::orthogonal_position::value );
    }

    typename RttiPolicy::id_type history_context_type() const
    {
      return historyContextType_;
    }

    friend bool operator<(
      const history_key & left, const history_key & right )
    {
      return
        std::less< typename RttiPolicy::id_type >()( 
          left.historyContextType_, right.historyContextType_ ) ||
        ( ( left.historyContextType_ == right.historyContextType_ ) &&
          ( left.historizedOrthogonalRegion_ <
            right.historizedOrthogonalRegion_ ) );
    }

  private:
    //////////////////////////////////////////////////////////////////////////
    history_key(
      typename RttiPolicy::id_type historyContextType, 
      orthogonal_position_type historizedOrthogonalRegion
    ) :
      historyContextType_( historyContextType ),
      historizedOrthogonalRegion_( historizedOrthogonalRegion )
    {
    }

    const typename RttiPolicy::id_type historyContextType_;
    const orthogonal_position_type historizedOrthogonalRegion_;
};



} // namespace detail



//////////////////////////////////////////////////////////////////////////////
template< class MostDerived,
          class InitialState, 
          class Allocator = std::allocator< void >,
          class ExceptionTranslator = null_exception_translator >
class state_machine : noncopyable
{
  public:
    //////////////////////////////////////////////////////////////////////////
    typedef Allocator allocator_type;
    typedef detail::rtti_policy rtti_policy_type;
    typedef event_base event_base_type;
    typedef intrusive_ptr< const event_base_type > event_base_ptr_type;

    void initiate()
    {
      terminate();

      {
        terminator guard( *this );
        detail::result_utility::get_result( translator_(
          initial_construct_function( *this ),
          exception_event_handler( *this ) ) );
        guard.dismiss();
      }

      process_queued_events();
    }

    void terminate()
    {
      terminator guard( *this );
      detail::result_utility::get_result( translator_(
        terminate_function( *this ),
        exception_event_handler( *this ) ) );
      guard.dismiss();
    }

    bool terminated() const
    {
      return pOutermostState_ == 0;
    }

    void process_event( const event_base_type & evt )
    {
      send_event( evt );
      process_queued_events();
    }

    template< class Target >
    Target state_cast() const
    {
      typedef detail::state_cast_impl< Target > impl;

      for ( typename state_list_type::const_iterator pCurrentLeafState =
              currentStates_.begin();
            pCurrentLeafState != currentStatesEnd_;
            ++pCurrentLeafState )
      {
        const state_base_type * pCurrentState(
          get_pointer( *pCurrentLeafState ) );

        while ( pCurrentState != 0 )
        {
          // The unnecessary try/catch overhead for pointer targets is
          // typically small compared to the cycles dynamic_cast needs
          #ifndef BOOST_NO_EXCEPTIONS
          try
          #endif
          {
            Target result = dynamic_cast< Target >(
              impl::deref_if_necessary( pCurrentState ) );

            if ( impl::found( result ) )
            {
              return result;
            }
          }
          #ifndef BOOST_NO_EXCEPTIONS
          // Intentionally swallow std::bad_cast exceptions. We'll throw one
          // ourselves when we fail to find a state that can be cast to Target
          catch ( const std::bad_cast & ) {}
          #endif

          pCurrentState = pCurrentState->outer_state_ptr();
        }
      }

      return impl::template not_found< Target >();
    }

    template< class Target >
    Target state_downcast() const
    {
      typedef detail::state_cast_impl< Target > impl;

      typename rtti_policy_type::id_type targetType =
        impl::template type_id< Target, rtti_policy_type::id_type >();

      for ( typename state_list_type::const_iterator pCurrentLeafState =
              currentStates_.begin();
            pCurrentLeafState != currentStatesEnd_;
            ++pCurrentLeafState )
      {
        const state_base_type * pCurrentState(
          get_pointer( *pCurrentLeafState ) );

        while ( pCurrentState != 0 )
        {
          if ( pCurrentState->dynamic_type() == targetType )
          {
            return static_cast< Target >(
              impl::deref_if_necessary( pCurrentState ) );
          }

          pCurrentState = pCurrentState->outer_state_ptr();
        }
      }

      return impl::template not_found< Target >();