| // 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; |
| namespace msm = boost::msm; |
| |
| // entry/exit/action/guard logging functors |
| #include "logging_functors.h" |
| |
| namespace // Concrete FSM implementation |
| { |
| // events |
| 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(next_song) |
| BOOST_MSM_EUML_EVENT(previous_song) |
| BOOST_MSM_EUML_EVENT(end_error) |
| BOOST_MSM_EUML_EVENT(error_found) |
| |
| // 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) |
| |
| |
| // Flags. Allow information about a property of the current state |
| BOOST_MSM_EUML_FLAG(PlayingPaused) |
| BOOST_MSM_EUML_FLAG(CDLoaded) |
| BOOST_MSM_EUML_FLAG(FirstSongPlaying) |
| |
| // Concrete FSM implementation |
| |
| // The list of FSM states |
| |
| BOOST_MSM_EUML_STATE(( Empty_Entry, |
| Empty_Exit, |
| attributes_ << no_attributes_, |
| configure_ << play // defer play |
| ), |
| Empty) |
| |
| BOOST_MSM_EUML_STATE(( Open_Entry, |
| Open_Exit, |
| attributes_ << no_attributes_, |
| configure_<< CDLoaded << play // defer play, flag state with CDLoaded |
| ), |
| Open) |
| |
| BOOST_MSM_EUML_STATE(( Stopped_Entry, |
| Stopped_Exit, |
| attributes_ << no_attributes_, |
| configure_<< CDLoaded // flag state with CDLoaded |
| ), |
| Stopped) |
| |
| // state not defining any entry or exit |
| BOOST_MSM_EUML_STATE(( no_action, |
| no_action, |
| attributes_ << no_attributes_, |
| configure_<< PlayingPaused << CDLoaded // flag state with CDLoaded and PlayingPaused |
| ), |
| Paused) |
| |
| BOOST_MSM_EUML_STATE(( AllOk_Entry,AllOk_Exit ),AllOk) |
| |
| // a terminate state |
| //BOOST_MSM_EUML_TERMINATE_STATE(( ErrorMode_Entry,ErrorMode_Exit ),ErrorMode) |
| // or as an interrupt state |
| BOOST_MSM_EUML_INTERRUPT_STATE(( end_error,ErrorMode_Entry,ErrorMode_Exit ),ErrorMode) |
| |
| // Playing is now a state machine itself. |
| // It has 3 substates |
| BOOST_MSM_EUML_STATE(( Song1_Entry, |
| Song1_Exit, |
| attributes_ << no_attributes_, |
| configure_<< FirstSongPlaying ),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 |
| no_action, // entry |
| no_action, // exit |
| attributes_ << no_attributes_, //attributes |
| configure_<< PlayingPaused << CDLoaded //flags |
| ),Playing_) |
| // choice of back-end |
| typedef msm::back::state_machine<Playing_> Playing_type; |
| Playing_type const Playing; |
| |
| // 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(( |
| Playing == Stopped + play / start_playback , |
| Playing == Paused + end_pause / resume_playback, |
| // +------------------------------------------------------------------------------+ |
| Empty == Open + open_close / close_drawer, |
| // +------------------------------------------------------------------------------+ |
| Open == Empty + open_close / open_drawer, |
| Open == Paused + open_close / stop_and_open, |
| Open == Stopped + open_close / open_drawer, |
| Open == Playing + open_close / stop_and_open, |
| // +------------------------------------------------------------------------------+ |
| Paused == Playing + pause / pause_playback, |
| // +------------------------------------------------------------------------------+ |
| Stopped == Playing + stop / stop_playback, |
| Stopped == Paused + stop / stop_playback, |
| Stopped == Empty + cd_detected [good_disk_format&& |
| (event_(cd_type)==Int_<DISK_CD>())] |
| / (store_cd_info,process_(play)), |
| Stopped == Stopped + stop, |
| ErrorMode == AllOk + error_found / report_error, |
| AllOk == ErrorMode+ end_error / report_end_error |
| // +------------------------------------------------------------------------------+ |
| ),transition_table) |
| |
| // create a state machine "on the fly" |
| BOOST_MSM_EUML_DECLARE_STATE_MACHINE(( transition_table, //STT |
| init_ << Empty<< AllOk, // 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", "Paused", "Open", "Empty", "Playing","AllOk","ErrorMode" }; |
| void pstate(player const& p) |
| { |
| // we have now several active states, which we show |
| for (unsigned int i=0;i<player::nr_regions::value;++i) |
| { |
| std::cout << " -> " << state_names[p.current_state()[i]] << 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(); |
| |
| // tests some flags |
| std::cout << "CDLoaded active:" << std::boolalpha |
| << p.is_flag_active<BOOST_MSM_EUML_FLAG_NAME(CDLoaded)>() << std::endl; //=> false (no CD yet) |
| // go to Open, call on_exit on Empty, then action, then on_entry on Open |
| p.process_event(open_close); pstate(p); |
| 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 |
| std::cout << "PlayingPaused active:" << std::boolalpha |
| << p.is_flag_active<BOOST_MSM_EUML_FLAG_NAME(PlayingPaused)>() << std::endl;//=> true |
| std::cout << "FirstSong active:" << std::boolalpha |
| << p.is_flag_active<BOOST_MSM_EUML_FLAG_NAME(FirstSongPlaying)>() << std::endl;//=> true |
| |
| // 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 |
| std::cout << "FirstSong active:" << std::boolalpha |
| << p.is_flag_active<BOOST_MSM_EUML_FLAG_NAME(FirstSongPlaying)>() << std::endl;//=> false |
| std::cout << "PlayingPaused active:" << std::boolalpha |
| << p.is_flag_active<BOOST_MSM_EUML_FLAG_NAME(PlayingPaused)>() << std::endl;//=> true |
| |
| // at this point, Play is active |
| p.process_event(pause); pstate(p); |
| std::cout << "PlayingPaused active:" << std::boolalpha |
| << p.is_flag_active<BOOST_MSM_EUML_FLAG_NAME(PlayingPaused)>() << std::endl;//=> true |
| |
| // go back to Playing |
| p.process_event(end_pause); pstate(p); |
| p.process_event(pause); pstate(p); |
| p.process_event(stop); pstate(p); |
| std::cout << "PlayingPaused active:" << std::boolalpha |
| << p.is_flag_active<BOOST_MSM_EUML_FLAG_NAME(PlayingPaused)>() << std::endl;//=> false |
| std::cout << "CDLoaded active:" << std::boolalpha |
| << p.is_flag_active<BOOST_MSM_EUML_FLAG_NAME(CDLoaded)>() << std::endl;//=> true |
| // by default, the flags are OR'ed but you can also use AND. Then the flag must be present in |
| // all of the active states |
| std::cout << "CDLoaded active with AND:" << std::boolalpha |
| << p.is_flag_active<BOOST_MSM_EUML_FLAG_NAME(CDLoaded),player::Flag_AND>() << std::endl;//=> false |
| |
| // event leading to the same state |
| // no action method called as none is defined in the transition table |
| p.process_event(stop); pstate(p); |
| |
| // event leading to a terminal/interrupt state |
| p.process_event(error_found); pstate(p); |
| // try generating more events |
| std::cout << "Trying to generate another event" << std::endl; // will not work, fsm is terminated or interrupted |
| p.process_event(play);pstate(p); |
| std::cout << "Trying to end the error" << std::endl; // will work only if ErrorMode is interrupt state |
| p.process_event(end_error);pstate(p); |
| std::cout << "Trying to generate another event" << std::endl; // will work only if ErrorMode is interrupt state |
| p.process_event(play);pstate(p); |
| |
| } |
| } |
| |
| int main() |
| { |
| test(); |
| return 0; |
| } |