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