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#include <iostream>
// back-end
#include <boost/msm/back/state_machine.hpp>
//front-end
#include <boost/msm/front/state_machine_def.hpp>
#include <boost/msm/front/euml/euml.hpp>
namespace msm = boost::msm;
namespace mpl = boost::mpl;
using namespace std;
// entry/exit/action/guard logging functors
#include "logging_functors.h"
namespace
{
// events
struct play_impl : msm::front::euml::euml_event<play_impl> {};
struct end_pause_impl : msm::front::euml::euml_event<end_pause_impl>{};
struct stop_impl : msm::front::euml::euml_event<stop_impl>{};
struct pause_impl : msm::front::euml::euml_event<pause_impl>{};
struct open_close_impl : msm::front::euml::euml_event<open_close_impl>{};
struct cd_detected_impl : msm::front::euml::euml_event<cd_detected_impl>{};
struct next_song_impl : msm::front::euml::euml_event<next_song_impl>{};
struct previous_song_impl : msm::front::euml::euml_event<previous_song_impl>{};
// define some dummy instances for use in the transition table
// it is also possible to default-construct them instead:
// struct play {};
// inside the table: play()
play_impl play;
end_pause_impl end_pause;
stop_impl stop;
pause_impl pause;
open_close_impl open_close;
cd_detected_impl cd_detected;
next_song_impl next_song;
previous_song_impl previous_song;
// The list of FSM states
// they have to be declared outside of the front-end only to make VC happy :(
// note: gcc would have no problem
struct Empty_impl : public msm::front::state<> , public msm::front::euml::euml_state<Empty_impl>
{
// every (optional) entry/exit methods get the event passed.
template <class Event,class FSM>
void on_entry(Event const&,FSM& ) {std::cout << "entering: Empty" << std::endl;}
template <class Event,class FSM>
void on_exit(Event const&,FSM& ) {std::cout << "leaving: Empty" << std::endl;}
};
struct Open_impl : public msm::front::state<> , public msm::front::euml::euml_state<Open_impl>
{
template <class Event,class FSM>
void on_entry(Event const& ,FSM&) {std::cout << "entering: Open" << std::endl;}
template <class Event,class FSM>
void on_exit(Event const&,FSM& ) {std::cout << "leaving: Open" << std::endl;}
};
struct Stopped_impl : public msm::front::state<> , public msm::front::euml::euml_state<Stopped_impl>
{
template <class Event,class FSM>
void on_entry(Event const& ,FSM&) {std::cout << "entering: Stopped" << std::endl;}
template <class Event,class FSM>
void on_exit(Event const&,FSM& ) {std::cout << "leaving: Stopped" << std::endl;}
};
// Playing Submachine front-end
struct Playing_ : public msm::front::state_machine_def<Playing_>
{
template <class Event,class FSM>
void on_entry(Event const& ,FSM&) {std::cout << "entering: Playing" << std::endl;}
template <class Event,class FSM>
void on_exit(Event const&,FSM& ) {std::cout << "leaving: Playing" << std::endl;}
struct Song1_ : public msm::front::state<> , public msm::front::euml::euml_state<Song1_>
{
template <class Event,class FSM>
void on_entry(Event const& ,FSM&) {std::cout << "entering: Song1" << std::endl;}
template <class Event,class FSM>
void on_exit(Event const&,FSM& ) {std::cout << "leaving: Song1" << std::endl;}
};
struct Song2_ : public msm::front::state<> , public msm::front::euml::euml_state<Song2_>
{
template <class Event,class FSM>
void on_entry(Event const& ,FSM&) {std::cout << "entering: Song2" << std::endl;}
template <class Event,class FSM>
void on_exit(Event const&,FSM& ) {std::cout << "leaving: Song2" << std::endl;}
};
struct Song3_ : public msm::front::state<> , public msm::front::euml::euml_state<Song3_>
{
template <class Event,class FSM>
void on_entry(Event const& ,FSM&) {std::cout << "entering: Song3" << std::endl;}
template <class Event,class FSM>
void on_exit(Event const&,FSM& ) {std::cout << "leaving: Song3" << std::endl;}
};
// to make the transition table more readable
// VC seems to need them static
static Song1_ Song1;
static Song2_ Song2;
static Song3_ Song3;
typedef Song1_ initial_state;
// Playing has a transition table
BOOST_MSM_EUML_DECLARE_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
// +------------------------------------------------------------------------------+
),transition_table )
};
// Playing Submachine back-end
typedef boost::msm::back::state_machine<Playing_> Playing_impl;
// state not defining any entry or exit
struct Paused_impl : public msm::front::state<> , public msm::front::euml::euml_state<Paused_impl>
{
};
//to make the transition table more readable
Empty_impl const Empty;
Open_impl const Open;
Stopped_impl const Stopped;
Playing_impl const Playing;
Paused_impl const Paused;
// front-end: define the FSM structure
struct player_ : public msm::front::state_machine_def<player_>
{
// the initial state of the player SM. Must be defined
typedef Empty_impl initial_state;
// Transition table for player
// replaces the old transition table
BOOST_MSM_EUML_DECLARE_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 /(store_cd_info,
msm::front::euml::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)
// Replaces the default no-transition response.
template <class FSM,class Event>
void no_transition(Event const& e, FSM&,int state)
{
std::cout << "no transition from state " << state
<< " on event " << typeid(e).name() << std::endl;
}
};
// Pick a 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);
p.process_event(open_close); pstate(p);
p.process_event(cd_detected); pstate(p);
// 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
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 it is not present in the transition table
p.process_event(stop); pstate(p);
}
}
int main()
{
test();
return 0;
}
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