| // Copyright 2010 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) |
| |
| #include <vector> |
| #include <iostream> |
| |
| #include <boost/msm/back/state_machine.hpp> |
| #include <boost/msm/front/euml/euml.hpp> |
| |
| using namespace std; |
| using namespace boost::msm::front::euml; |
| using namespace boost::msm::front; |
| namespace msm = boost::msm; |
| |
| // entry/exit/action/guard logging functors |
| #include "logging_functors.h" |
| |
| namespace // Concrete FSM implementation |
| { |
| // events |
| // note that unlike the SimpleTutorial, events must derive from euml_event. |
| BOOST_MSM_EUML_EVENT(play) |
| BOOST_MSM_EUML_EVENT(end_pause) |
| BOOST_MSM_EUML_EVENT(stop) |
| BOOST_MSM_EUML_EVENT(pause) |
| BOOST_MSM_EUML_EVENT(open_close) |
| BOOST_MSM_EUML_EVENT(internal_event) |
| BOOST_MSM_EUML_EVENT(next_song) |
| BOOST_MSM_EUML_EVENT(previous_song) |
| |
| // A "complicated" event type that carries some data. |
| BOOST_MSM_EUML_DECLARE_ATTRIBUTE(std::string,cd_name) |
| BOOST_MSM_EUML_DECLARE_ATTRIBUTE(DiskTypeEnum,cd_type) |
| BOOST_MSM_EUML_ATTRIBUTES((attributes_ << cd_name << cd_type ), cd_detected_attributes) |
| BOOST_MSM_EUML_EVENT_WITH_ATTRIBUTES(cd_detected,cd_detected_attributes) |
| |
| // Concrete FSM implementation |
| |
| // The list of FSM states |
| BOOST_MSM_EUML_STATE(( Empty_Entry,Empty_Exit ),Empty) |
| |
| // we just declare a state type but do not create any instance as we want to inherit from this type |
| BOOST_MSM_EUML_DECLARE_STATE((Open_Entry,Open_Exit),Open_def) |
| // derive to be able to add an internal transition table |
| struct Open_impl : public Open_def |
| { |
| BOOST_MSM_EUML_DECLARE_INTERNAL_TRANSITION_TABLE(( |
| open_close [internal_guard1] / internal_action1 , |
| open_close [internal_guard2] / internal_action2 , |
| internal_event / internal_action |
| )) |
| }; |
| // declare an instance for the stt as we are manually declaring a state |
| Open_impl const Open; |
| BOOST_MSM_EUML_STATE(( Stopped_Entry,Stopped_Exit ),Stopped) |
| |
| // Playing is a state machine itself. |
| // It has 3 substates |
| BOOST_MSM_EUML_STATE(( Song1_Entry,Song1_Exit ),Song1) |
| BOOST_MSM_EUML_STATE(( Song2_Entry,Song2_Exit ),Song2) |
| BOOST_MSM_EUML_STATE(( Song3_Entry,Song3_Exit ),Song3) |
| |
| // Playing has a transition table |
| BOOST_MSM_EUML_TRANSITION_TABLE(( |
| // +------------------------------------------------------------------------------+ |
| Song2 == Song1 + next_song / start_next_song, |
| Song1 == Song2 + previous_song / start_prev_song, |
| Song3 == Song2 + next_song / start_next_song, |
| Song2 == Song3 + previous_song / start_prev_song |
| // +------------------------------------------------------------------------------+ |
| ),playing_transition_table ) |
| |
| BOOST_MSM_EUML_DECLARE_STATE_MACHINE( (playing_transition_table, //STT |
| init_ << Song1 // Init State |
| ),Playing_def) |
| |
| // some action for the internal transition |
| BOOST_MSM_EUML_ACTION(playing_internal_action) |
| { |
| template <class FSM,class EVT,class SourceState,class TargetState> |
| void operator()(EVT const&, FSM& ,SourceState& ,TargetState& ) |
| { |
| cout << "Playing::internal action" << endl; |
| } |
| }; |
| // derive to be able to add an internal transition table |
| struct Playing_ : public Playing_def |
| { |
| BOOST_MSM_EUML_DECLARE_INTERNAL_TRANSITION_TABLE(( |
| internal_event / playing_internal_action |
| )) |
| }; |
| // choice of back-end |
| typedef msm::back::state_machine<Playing_> Playing_type; |
| Playing_type const Playing; |
| |
| |
| // state not needing any entry or exit |
| BOOST_MSM_EUML_STATE((),Paused) |
| |
| // guard conditions |
| BOOST_MSM_EUML_ACTION(good_disk_format) |
| { |
| template <class FSM,class EVT,class SourceState,class TargetState> |
| bool operator()(EVT const& evt,FSM&,SourceState& ,TargetState& ) |
| { |
| // to test a guard condition, let's say we understand only CDs, not DVD |
| if (evt.get_attribute(cd_type)!=DISK_CD) |
| { |
| std::cout << "wrong disk, sorry" << std::endl; |
| // just for logging, does not block any transition |
| return true; |
| } |
| std::cout << "good disk" << std::endl; |
| return true; |
| } |
| }; |
| // replaces the old transition table |
| BOOST_MSM_EUML_TRANSITION_TABLE(( |
| Stopped + play / start_playback == Playing , |
| Stopped + open_close / open_drawer == Open , |
| Stopped + stop == Stopped , |
| // +------------------------------------------------------------------------------+ |
| Open + open_close / close_drawer == Empty , |
| // +------------------------------------------------------------------------------+ |
| Empty + open_close / open_drawer == Open , |
| Empty + cd_detected |
| [good_disk_format&&(event_(cd_type)==Int_<DISK_CD>())] |
| / (store_cd_info,process_(play)) |
| == Stopped , |
| // +------------------------------------------------------------------------------+ |
| Playing + stop / stop_playback == Stopped , |
| Playing + pause / pause_playback == Paused , |
| Playing + open_close / stop_and_open == Open , |
| // +------------------------------------------------------------------------------+ |
| Paused + end_pause / resume_playback == Playing , |
| Paused + stop / stop_playback == Stopped , |
| Paused + open_close / stop_and_open == Open |
| // +------------------------------------------------------------------------------+ |
| ),transition_table) |
| |
| |
| |
| // create a state machine "on the fly" |
| BOOST_MSM_EUML_DECLARE_STATE_MACHINE(( transition_table, //STT |
| init_ << Empty, // Init State |
| no_action, // Entry |
| no_action, // Exit |
| attributes_ << no_attributes_, // Attributes |
| configure_ << no_configure_, // configuration |
| Log_No_Transition // no_transition handler |
| ), |
| player_) //fsm name |
| |
| // choice of back-end |
| typedef msm::back::state_machine<player_> player; |
| |
| // |
| // Testing utilities. |
| // |
| static char const* const state_names[] = { "Stopped", "Open", "Empty", "Playing", "Paused" }; |
| void pstate(player const& p) |
| { |
| std::cout << " -> " << state_names[p.current_state()[0]] << std::endl; |
| } |
| |
| void test() |
| { |
| player p; |
| // needed to start the highest-level SM. This will call on_entry and mark the start of the SM |
| p.start(); |
| // go to Open, call on_exit on Empty, then action, then on_entry on Open |
| p.process_event(open_close); pstate(p); |
| std::cout << "sending internal event (not rejected)" << std::endl; |
| p.process_event(internal_event); |
| std::cout << "sending open_close event. Conflict with internal transitions (rejecting event)" << std::endl; |
| p.process_event(open_close); pstate(p); |
| // will be rejected, wrong disk type |
| p.process_event( |
| cd_detected("louie, louie",DISK_DVD)); pstate(p); |
| p.process_event( |
| cd_detected("louie, louie",DISK_CD)); pstate(p); |
| // no need to call play as the previous event does it in its action method |
| //p.process_event(play); |
| // at this point, Play is active |
| // make transition happen inside it. Player has no idea about this event but it's ok. |
| p.process_event(next_song);pstate(p); //2nd song active |
| p.process_event(next_song);pstate(p);//3rd song active |
| p.process_event(previous_song);pstate(p);//2nd song active |
| // event handled internally in Playing, without region checking |
| std::cout << "sending internal event (not rejected)" << std::endl; |
| p.process_event(internal_event); |
| |
| p.process_event(pause); pstate(p); |
| // go back to Playing |
| p.process_event(end_pause); pstate(p); |
| p.process_event(pause); pstate(p); |
| p.process_event(stop); pstate(p); |
| // event leading to the same state |
| // no action method called as none is defined in the transition table |
| p.process_event(stop); pstate(p); |
| // test call to no_transition |
| p.process_event(pause); pstate(p); |
| } |
| } |
| |
| int main() |
| { |
| test(); |
| return 0; |
| } |