Chris@16: // Copyright 2008 Christophe Henry
Chris@16: // henry UNDERSCORE christophe AT hotmail DOT com
Chris@16: // This is an extended version of the state machine available in the boost::mpl library
Chris@16: // Distributed under the same license as the original.
Chris@16: // Copyright for the original version:
Chris@16: // Copyright 2005 David Abrahams and Aleksey Gurtovoy. Distributed
Chris@16: // under the Boost Software License, Version 1.0. (See accompanying
Chris@16: // file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: #ifndef BOOST_MSM_BACK_FAVOR_COMPILE_TIME_H
Chris@16: #define BOOST_MSM_BACK_FAVOR_COMPILE_TIME_H
Chris@16: 
Chris@16: #include <utility>
Chris@16: #include <deque>
Chris@16: 
Chris@16: #include <boost/mpl/filter_view.hpp>
Chris@16: #include <boost/mpl/for_each.hpp>
Chris@16: #include <boost/mpl/bool.hpp>
Chris@16: #include <boost/any.hpp>
Chris@16: 
Chris@16: #include <boost/msm/common.hpp>
Chris@16: #include <boost/msm/back/metafunctions.hpp>
Chris@16: #include <boost/msm/back/common_types.hpp>
Chris@16: #include <boost/msm/back/dispatch_table.hpp>
Chris@16: 
Chris@16: namespace boost { namespace msm { namespace back 
Chris@16: {
Chris@16: 
Chris@16: template <class Fsm>
Chris@16: struct process_any_event_helper
Chris@16: {
Chris@16:     process_any_event_helper(msm::back::HandledEnum& res_,Fsm* self_,::boost::any any_event_):
Chris@16:     res(res_),self(self_),any_event(any_event_),finished(false){}
Chris@16:     template <class Event>
Chris@16:     void operator()(boost::msm::wrap<Event> const&)
Chris@16:     {
Chris@16:         if ( ! finished && ::boost::any_cast<Event>(&any_event)!=0)
Chris@16:         {
Chris@16:             finished = true;
Chris@16:             res = self->process_event_internal(::boost::any_cast<Event>(any_event),false);
Chris@16:  
Chris@16:         }
Chris@16:     }
Chris@16: private:
Chris@16:     msm::back::HandledEnum&     res;
Chris@16:     Fsm*                        self;
Chris@16:     ::boost::any                any_event;
Chris@16:     bool                        finished;
Chris@16: };
Chris@16: 
Chris@16: #define BOOST_MSM_BACK_GENERATE_PROCESS_EVENT(fsmname)                                              \
Chris@16:     namespace boost { namespace msm { namespace back{                                               \
Chris@16:     template<>                                                                                      \
Chris@16:     ::boost::msm::back::HandledEnum fsmname::process_any_event( ::boost::any const& any_event)      \
Chris@16:     {                                                                                               \
Chris@16:         typedef ::boost::msm::back::recursive_get_transition_table<fsmname>::type stt;              \
Chris@16:         typedef ::boost::msm::back::generate_event_set<stt>::type stt_events;                       \
Chris@16:         typedef ::boost::msm::back::recursive_get_internal_transition_table<fsmname, ::boost::mpl::true_ >::type istt;    \
Chris@16:         typedef ::boost::msm::back::generate_event_set<create_real_stt<fsmname,istt>::type >::type istt_events;  \
Chris@16:         typedef ::boost::msm::back::set_insert_range<stt_events,istt_events>::type all_events;      \
Chris@16:         ::boost::msm::back::HandledEnum res= ::boost::msm::back::HANDLED_FALSE;                     \
Chris@16:         ::boost::mpl::for_each<all_events, ::boost::msm::wrap< ::boost::mpl::placeholders::_1> >    \
Chris@16:         (::boost::msm::back::process_any_event_helper<fsmname>(res,this,any_event));                \
Chris@16:         return res;                                                                                 \
Chris@16:     }                                                                                               \
Chris@16:     }}}
Chris@16: 
Chris@16: struct favor_compile_time 
Chris@16: {
Chris@16:     typedef int compile_policy;
Chris@16:     typedef ::boost::mpl::false_ add_forwarding_rows;
Chris@16: };
Chris@16: 
Chris@16: // Generates a singleton runtime lookup table that maps current state
Chris@16: // to a function that makes the SM take its transition on the given
Chris@16: // Event type.
Chris@16: template <class Fsm,class Stt, class Event>
Chris@16: struct dispatch_table < Fsm, Stt, Event, ::boost::msm::back::favor_compile_time>
Chris@16: {
Chris@16:  private:
Chris@16:     // This is a table of these function pointers.
Chris@16:     typedef HandledEnum (*cell)(Fsm&, int,int,Event const&);
Chris@16:     typedef bool (*guard)(Fsm&, Event const&);
Chris@16: 
Chris@16:     // Compute the maximum state value in the sm so we know how big
Chris@16:     // to make the table
Chris@16:     typedef typename generate_state_set<Stt>::type state_list;
Chris@16:     BOOST_STATIC_CONSTANT(int, max_state = ( ::boost::mpl::size<state_list>::value));
Chris@16: 
Chris@16:     struct chain_row 
Chris@16:     {
Chris@16:         HandledEnum operator()(Fsm& fsm, int region,int state,Event const& evt) const
Chris@16:         {
Chris@16:             HandledEnum res = HANDLED_FALSE;
Chris@16:             typename std::deque<cell>::const_iterator it = one_state.begin();
Chris@16:             while (it != one_state.end() && (res != HANDLED_TRUE && res != HANDLED_DEFERRED ))
Chris@16:             {
Chris@16:                 HandledEnum handled = (*it)(fsm,region,state,evt);
Chris@16:                 // reject is considered as erasing an error (HANDLED_FALSE)
Chris@16:                 if ((HANDLED_FALSE==handled) && (HANDLED_GUARD_REJECT==res) )
Chris@16:                     res = HANDLED_GUARD_REJECT;
Chris@16:                 else
Chris@16:                     res = handled;
Chris@16:                 ++it;
Chris@16:             }
Chris@16:             return res;
Chris@16:         }
Chris@16:         std::deque<cell> one_state;
Chris@16:     };
Chris@16:     template <class TransitionState>
Chris@16:     static HandledEnum call_submachine(Fsm& fsm, int , int , Event const& evt)
Chris@16:     {
Chris@16:         return (fsm.template get_state<TransitionState&>()).process_any_event( ::boost::any(evt));
Chris@16:     }
Chris@16:     // A function object for use with mpl::for_each that stuffs
Chris@16:     // transitions into cells.
Chris@16:     struct init_cell
Chris@16:     {
Chris@16:         init_cell(dispatch_table* self_)
Chris@16:           : self(self_)
Chris@16:         {}
Chris@16:         // version for transition event not base of our event
Chris@16:         template <class Transition>
Chris@16:         typename ::boost::disable_if<
Chris@16:             typename ::boost::is_same<typename Transition::current_state_type,Fsm>::type
Chris@16:         ,void>::type
Chris@16:         init_event_base_case(Transition const&, ::boost::mpl::true_ const &) const
Chris@16:         {
Chris@16:             typedef typename create_stt<Fsm>::type stt; 
Chris@16:             BOOST_STATIC_CONSTANT(int, state_id = 
Chris@16:                 (get_state_id<stt,typename Transition::current_state_type>::value));
Chris@16:             self->entries[state_id+1].one_state.push_front(reinterpret_cast<cell>(&Transition::execute));
Chris@16:         }
Chris@16:         template <class Transition>
Chris@16:         typename ::boost::enable_if<
Chris@16:             typename ::boost::is_same<typename Transition::current_state_type,Fsm>::type
Chris@16:         ,void>::type
Chris@16:         init_event_base_case(Transition const&, ::boost::mpl::true_ const &) const
Chris@16:         {
Chris@16:             self->entries[0].one_state.push_front(reinterpret_cast<cell>(&Transition::execute));
Chris@16:         }
Chris@16: 
Chris@16:         // version for transition event base of our event
Chris@16:         template <class Transition>
Chris@16:         typename ::boost::disable_if<
Chris@16:             typename ::boost::is_same<typename Transition::current_state_type,Fsm>::type
Chris@16:         ,void>::type
Chris@16:         init_event_base_case(Transition const&, ::boost::mpl::false_ const &) const
Chris@16:         {
Chris@16:             typedef typename create_stt<Fsm>::type stt; 
Chris@16:             BOOST_STATIC_CONSTANT(int, state_id = 
Chris@16:                 (get_state_id<stt,typename Transition::current_state_type>::value));
Chris@16:             self->entries[state_id+1].one_state.push_front(&Transition::execute);
Chris@16:         }
Chris@16:         template <class Transition>
Chris@16:         typename ::boost::enable_if<
Chris@16:             typename ::boost::is_same<typename Transition::current_state_type,Fsm>::type
Chris@16:         ,void>::type
Chris@16:         init_event_base_case(Transition const&, ::boost::mpl::false_ const &) const
Chris@16:         {
Chris@16:             self->entries[0].one_state.push_front(&Transition::execute);
Chris@16:         }
Chris@16:         // Cell initializer function object, used with mpl::for_each
Chris@16:         template <class Transition>
Chris@16:         typename ::boost::enable_if<typename has_not_real_row_tag<Transition>::type,void >::type
Chris@16:             operator()(Transition const&,boost::msm::back::dummy<0> = 0) const
Chris@16:         {
Chris@16:             // version for not real rows. No problem because irrelevant for process_event
Chris@16:         }
Chris@16:         template <class Transition>
Chris@16:         typename ::boost::disable_if<typename has_not_real_row_tag<Transition>::type,void >::type
Chris@16:         operator()(Transition const& tr,boost::msm::back::dummy<1> = 0) const
Chris@16:         {
Chris@16:             //only if the transition event is a base of our event is the reinterpret_case safe
Chris@16:             init_event_base_case(tr,
Chris@16:                 ::boost::mpl::bool_< 
Chris@16:                     ::boost::is_base_of<typename Transition::transition_event,Event>::type::value>() );
Chris@16:         }
Chris@16:     
Chris@16:         dispatch_table* self;
Chris@16:     };
Chris@16: 
Chris@16:     // Cell default-initializer function object, used with mpl::for_each
Chris@16:     // initializes with call_no_transition, defer_transition or default_eventless_transition
Chris@16:     // variant for non-anonymous transitions
Chris@16:     template <class EventType,class Enable=void>
Chris@16:     struct default_init_cell
Chris@16:     {
Chris@16:         default_init_cell(dispatch_table* self_,chain_row* tofill_entries_)
Chris@16:             : self(self_),tofill_entries(tofill_entries_)
Chris@16:         {}
Chris@16:         template <bool deferred,bool composite, int some_dummy=0>
Chris@16:         struct helper
Chris@16:         {};
Chris@16:         template <int some_dummy> struct helper<true,false,some_dummy> 
Chris@16:         {
Chris@16:             template <class State>
Chris@16:             static void execute(boost::msm::wrap<State> const&,chain_row* tofill)
Chris@16:             {
Chris@16:                 typedef typename create_stt<Fsm>::type stt; 
Chris@16:                 BOOST_STATIC_CONSTANT(int, state_id = (get_state_id<stt,State>::value));
Chris@16:                 cell call_no_transition = &Fsm::defer_transition;
Chris@16:                 tofill[state_id+1].one_state.push_back(call_no_transition);
Chris@16:             }
Chris@16:         };
Chris@16:         template <int some_dummy> struct helper<true,true,some_dummy> 
Chris@16:         {
Chris@16:             template <class State>
Chris@16:             static void execute(boost::msm::wrap<State> const&,chain_row* tofill)
Chris@16:             {
Chris@16:                 typedef typename create_stt<Fsm>::type stt; 
Chris@16:                 BOOST_STATIC_CONSTANT(int, state_id = (get_state_id<stt,State>::value));
Chris@16:                 cell call_no_transition = &Fsm::defer_transition;
Chris@16:                 tofill[state_id+1].one_state.push_back(call_no_transition);
Chris@16:             }
Chris@16:         };
Chris@16:         template <int some_dummy> struct helper<false,true,some_dummy> 
Chris@16:         {
Chris@16:             template <class State>
Chris@16:             static
Chris@16:             typename ::boost::enable_if<
Chris@16:                 typename ::boost::is_same<State,Fsm>::type
Chris@16:             ,void>::type
Chris@16:             execute(boost::msm::wrap<State> const&,chain_row* tofill,boost::msm::back::dummy<0> = 0)
Chris@16:             {
Chris@16:                 // for internal tables
Chris@16:                 cell call_no_transition_internal = &Fsm::call_no_transition;
Chris@16:                 tofill[0].one_state.push_front(call_no_transition_internal);
Chris@16:             }
Chris@16:             template <class State>
Chris@16:             static
Chris@16:             typename ::boost::disable_if<
Chris@16:                 typename ::boost::is_same<State,Fsm>::type
Chris@16:             ,void>::type
Chris@16:             execute(boost::msm::wrap<State> const&,chain_row* tofill,boost::msm::back::dummy<1> = 0)
Chris@16:             {
Chris@16:                 typedef typename create_stt<Fsm>::type stt; 
Chris@16:                 BOOST_STATIC_CONSTANT(int, state_id = (get_state_id<stt,State>::value));
Chris@16:                 cell call_no_transition = &call_submachine< State >;
Chris@16:                 tofill[state_id+1].one_state.push_front(call_no_transition);
Chris@16:             }
Chris@16:         };
Chris@16:         template <int some_dummy> struct helper<false,false,some_dummy> 
Chris@16:         {
Chris@16:             template <class State>
Chris@16:             static void execute(boost::msm::wrap<State> const&,chain_row* tofill)
Chris@16:             {
Chris@16:                 typedef typename create_stt<Fsm>::type stt; 
Chris@16:                 BOOST_STATIC_CONSTANT(int, state_id = (get_state_id<stt,State>::value));
Chris@16:                 cell call_no_transition = &Fsm::call_no_transition;
Chris@16:                 tofill[state_id+1].one_state.push_back(call_no_transition);
Chris@16:             }
Chris@16:         };
Chris@16:         template <class State>
Chris@16:         void operator()(boost::msm::wrap<State> const& s)
Chris@16:         {
Chris@16:             helper<has_state_delayed_event<State,Event>::type::value,
Chris@16:                    is_composite_state<State>::type::value>::execute(s,tofill_entries);
Chris@16:         }
Chris@16:         dispatch_table* self;
Chris@16:         chain_row* tofill_entries;
Chris@16:     };
Chris@16: 
Chris@16:     // variant for anonymous transitions
Chris@16:     template <class EventType>
Chris@16:     struct default_init_cell<EventType,
Chris@16:                              typename ::boost::enable_if<
Chris@16:                                 typename is_completion_event<EventType>::type>::type>
Chris@16:     {
Chris@16:         default_init_cell(dispatch_table* self_,chain_row* tofill_entries_)
Chris@16:             : self(self_),tofill_entries(tofill_entries_)
Chris@16:         {}
Chris@16: 
Chris@16:         // this event is a compound one (not a real one, just one for use in event-less transitions)
Chris@16:         // Note this event cannot be used as deferred!
Chris@16:         template <class State>
Chris@16:         void operator()(boost::msm::wrap<State> const&)
Chris@16:         {
Chris@16:             typedef typename create_stt<Fsm>::type stt; 
Chris@16:             BOOST_STATIC_CONSTANT(int, state_id = (get_state_id<stt,State>::value));
Chris@16:             cell call_no_transition = &Fsm::default_eventless_transition;
Chris@16:             tofill_entries[state_id+1].one_state.push_back(call_no_transition);
Chris@16:         }
Chris@16: 
Chris@16:         dispatch_table* self;
Chris@16:         chain_row* tofill_entries;
Chris@16:     };
Chris@16: 
Chris@16:  public:
Chris@16:     // initialize the dispatch table for a given Event and Fsm
Chris@16:     dispatch_table()
Chris@16:     {
Chris@16:         // Initialize cells for no transition
Chris@16:         ::boost::mpl::for_each<
Chris@16:             ::boost::mpl::filter_view<
Chris@16:                     Stt, ::boost::is_base_of<transition_event< ::boost::mpl::placeholders::_>, Event> > >
Chris@16:         (init_cell(this));
Chris@16: 
Chris@16:         ::boost::mpl::for_each<
Chris@16:             typename generate_state_set<Stt>::type, 
Chris@16:             boost::msm::wrap< ::boost::mpl::placeholders::_1> >
Chris@16:          (default_init_cell<Event>(this,entries));
Chris@16: 
Chris@16:     }
Chris@16: 
Chris@16:     // The singleton instance.
Chris@16:     static const dispatch_table instance;
Chris@16: 
Chris@16:  public: // data members
Chris@16:      chain_row entries[max_state+1];
Chris@16: };
Chris@16: 
Chris@16: template <class Fsm,class Stt, class Event>
Chris@16: const boost::msm::back::dispatch_table<Fsm,Stt, Event,favor_compile_time>
Chris@16: dispatch_table<Fsm,Stt, Event,favor_compile_time>::instance;
Chris@16: 
Chris@16: }}} // boost::msm::back
Chris@16: 
Chris@16: #endif //BOOST_MSM_BACK_FAVOR_COMPILE_TIME_H