[ceph.git] / ceph / src / boost / libs / msm / doc / HTML / examples / CompositeTutorial.cpp

// 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 <iostream>
// back-end
#include <boost/msm/back/state_machine.hpp>
//front-end
#include <boost/msm/front/state_machine_def.hpp>

namespace msm = boost::msm;
namespace mpl = boost::mpl;

namespace  // Concrete FSM implementation
{
    // events
    struct play {};
    struct end_pause {};
    struct stop {};
    struct pause {};
    struct open_close {};
    struct NextSong {};
    struct PreviousSong {};

    // A "complicated" event type that carries some data.
    struct cd_detected
    {
        cd_detected(std::string name)
            : name(name)
        {}

        std::string name;
    };

    // front-end: define the FSM structure 
    struct player_ : public msm::front::state_machine_def<player_>
    {
        template <class Event,class FSM>
        void on_entry(Event const& ,FSM&) {std::cout << "entering: Player" << std::endl;}
        template <class Event,class FSM>
        void on_exit(Event const&,FSM& ) {std::cout << "leaving: Player" << std::endl;}

        // The list of FSM states
        struct Empty : public msm::front::state<> 
        {
            // 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 : public msm::front::state<> 
        { 
            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 : public msm::front::state<> 
        { 
            // when stopped, the CD is loaded
            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;}
        };

        // the player state machine contains a state which is himself a state machine
        // as you see, no need to declare it anywhere so Playing can be developed separately
        // by another team in another module. For simplicity I just declare it inside player
        struct Playing_ : public msm::front::state_machine_def<Playing_>
        {
            // when playing, the CD is loaded and we are in either pause or playing (duh)
            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;}

            // The list of FSM states
            struct Song1 : public msm::front::state<>
            {
                template <class Event,class FSM>
                void on_entry(Event const&,FSM& ) {std::cout << "starting: First song" << std::endl;}
                template <class Event,class FSM>
                void on_exit(Event const&,FSM& ) {std::cout << "finishing: First Song" << std::endl;}

            };
            struct Song2 : public msm::front::state<>
            { 
                template <class Event,class FSM>
                void on_entry(Event const&,FSM& ) {std::cout << "starting: Second song" << std::endl;}
                template <class Event,class FSM>
                void on_exit(Event const&,FSM& ) {std::cout << "finishing: Second Song" << std::endl;}
            };
            struct Song3 : public msm::front::state<>
            { 
                template <class Event,class FSM>
                void on_entry(Event const&,FSM& ) {std::cout << "starting: Third song" << std::endl;}
                template <class Event,class FSM>
                void on_exit(Event const&,FSM& ) {std::cout << "finishing: Third Song" << std::endl;}
            };
            // the initial state. Must be defined
            typedef Song1 initial_state;
            // transition actions
            void start_next_song(NextSong const&)       { std::cout << "Playing::start_next_song\n"; }
            void start_prev_song(PreviousSong const&)       { std::cout << "Playing::start_prev_song\n"; }
            // guard conditions

            typedef Playing_ pl; // makes transition table cleaner
            // Transition table for Playing
            struct transition_table : mpl::vector4<
                //      Start     Event         Next      Action               Guard
                //    +---------+-------------+---------+---------------------+----------------------+
                a_row < Song1   , NextSong    , Song2   , &pl::start_next_song                       >,
                a_row < Song2   , PreviousSong, Song1   , &pl::start_prev_song                       >,
                a_row < Song2   , NextSong    , Song3   , &pl::start_next_song                       >,
                a_row < Song3   , PreviousSong, Song2   , &pl::start_prev_song                       >
                //    +---------+-------------+---------+---------------------+----------------------+
            > {};
            // 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;
            }
        };
        // back-end
        typedef msm::back::state_machine<Playing_> Playing;


        // state not defining any entry or exit
        struct Paused : public msm::front::state<>
        {
        };

        // the initial state of the player SM. Must be defined
        typedef Empty initial_state;

        // transition actions
        void start_playback(play const&)       { std::cout << "player::start_playback\n"; }
        void open_drawer(open_close const&)    { std::cout << "player::open_drawer\n"; }
        void close_drawer(open_close const&)   { std::cout << "player::close_drawer\n"; }
        void store_cd_info(cd_detected const& cd) {std::cout << "player::store_cd_info\n";}
        void stop_playback(stop const&)        { std::cout << "player::stop_playback\n"; }
        void pause_playback(pause const&)      { std::cout << "player::pause_playback\n"; }
        void resume_playback(end_pause const&)      { std::cout << "player::resume_playback\n"; }
        void stop_and_open(open_close const&)  { std::cout << "player::stop_and_open\n"; }
        void stopped_again(stop const&){std::cout << "player::stopped_again\n";}
        // guard conditions

        typedef player_ p; // makes transition table cleaner

        // Transition table for player
        struct transition_table : mpl::vector<
            //      Start     Event         Next      Action               Guard
            //    +---------+-------------+---------+---------------------+----------------------+
            a_row < Stopped , play        , Playing , &p::start_playback                         >,
            a_row < Stopped , open_close  , Open    , &p::open_drawer                            >,
            a_row < Stopped , stop        , Stopped , &p::stopped_again                          >,
            //    +---------+-------------+---------+---------------------+----------------------+
            a_row < Open    , open_close  , Empty   , &p::close_drawer                         >,
            //    +---------+-------------+---------+---------------------+----------------------+
            a_row < Empty   , open_close  , Open    , &p::open_drawer                          >,
            a_row < Empty   , cd_detected , Stopped , &p::store_cd_info                        >,
            //    +---------+-------------+---------+---------------------+----------------------+
            a_row < Playing , stop        , Stopped , &p::stop_playback                        >,
            a_row < Playing , pause       , Paused  , &p::pause_playback                       >,
            a_row < Playing , open_close  , Open    , &p::stop_and_open                        >,
            //    +---------+-------------+---------+---------------------+----------------------+
            a_row < Paused  , end_pause   , Playing , &p::resume_playback                      >,
            a_row < Paused  , stop        , Stopped , &p::stop_playback                        >,
            a_row < Paused  , open_close  , Open    , &p::stop_and_open                        >
            //    +---------+-------------+---------+---------------------+----------------------+
        > {};

        // 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("louie, louie"));
        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(NextSong());pstate(p); //2nd song active
        p.process_event(NextSong());pstate(p);//3rd song active
        p.process_event(PreviousSong());pstate(p);//2nd song active

        p.process_event(pause()); pstate(p);
        // go back to Playing
        // as you see, it starts back from the original state
        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
        p.process_event(stop());  pstate(p);
        // stop the fsm (call on_exit's, including the submachines)
        p.process_event(play());
        std::cout << "stop fsm" << std::endl;
        p.stop();
        std::cout << "restart fsm" << std::endl;
        p.start();
    }
}

int main()
{
    test();
    return 0;
}
Commit	Line	Data
7c673cae FG	1	// Copyright 2010 Christophe Henry
	2	// henry UNDERSCORE christophe AT hotmail DOT com
	3	// This is an extended version of the state machine available in the boost::mpl library
	4	// Distributed under the same license as the original.
	5	// Copyright for the original version:
	6	// Copyright 2005 David Abrahams and Aleksey Gurtovoy. Distributed
	7	// under the Boost Software License, Version 1.0. (See accompanying
	8	// file LICENSE_1_0.txt or copy at
	9	// http://www.boost.org/LICENSE_1_0.txt)
	10
	11	#include <iostream>
	12	// back-end
	13	#include <boost/msm/back/state_machine.hpp>
	14	//front-end
	15	#include <boost/msm/front/state_machine_def.hpp>
	16
	17	namespace msm = boost::msm;
	18	namespace mpl = boost::mpl;
	19
	20	namespace // Concrete FSM implementation
	21	{
	22	// events
	23	struct play {};
	24	struct end_pause {};
	25	struct stop {};
	26	struct pause {};
	27	struct open_close {};
	28	struct NextSong {};
	29	struct PreviousSong {};
	30
	31	// A "complicated" event type that carries some data.
	32	struct cd_detected
	33	{
	34	cd_detected(std::string name)
	35	: name(name)
	36	{}
	37
	38	std::string name;
	39	};
	40
	41	// front-end: define the FSM structure
	42	struct player_ : public msm::front::state_machine_def<player_>
	43	{
	44	template <class Event,class FSM>
	45	void on_entry(Event const& ,FSM&) {std::cout << "entering: Player" << std::endl;}
	46	template <class Event,class FSM>
	47	void on_exit(Event const&,FSM& ) {std::cout << "leaving: Player" << std::endl;}
	48
	49	// The list of FSM states
	50	struct Empty : public msm::front::state<>
	51	{
	52	// every (optional) entry/exit methods get the event passed.
	53	template <class Event,class FSM>
	54	void on_entry(Event const&,FSM& ) {std::cout << "entering: Empty" << std::endl;}
	55	template <class Event,class FSM>
	56	void on_exit(Event const&,FSM& ) {std::cout << "leaving: Empty" << std::endl;}
	57	};
	58	struct Open : public msm::front::state<>
	59	{
	60	template <class Event,class FSM>
	61	void on_entry(Event const&,FSM& ) {std::cout << "entering: Open" << std::endl;}
	62	template <class Event,class FSM>
	63	void on_exit(Event const&,FSM& ) {std::cout << "leaving: Open" << std::endl;}
	64	};
65
66	struct Stopped : public msm::front::state<>
67	{
68	// when stopped, the CD is loaded
69	template <class Event,class FSM>
70	void on_entry(Event const&,FSM& ) {std::cout << "entering: Stopped" << std::endl;}
71	template <class Event,class FSM>
72	void on_exit(Event const&,FSM& ) {std::cout << "leaving: Stopped" << std::endl;}
73	};
74
75	// the player state machine contains a state which is himself a state machine
76	// as you see, no need to declare it anywhere so Playing can be developed separately
77	// by another team in another module. For simplicity I just declare it inside player
78	struct Playing_ : public msm::front::state_machine_def<Playing_>
79	{
80	// when playing, the CD is loaded and we are in either pause or playing (duh)
81	template <class Event,class FSM>
82	void on_entry(Event const&,FSM& ) {std::cout << "entering: Playing" << std::endl;}
83	template <class Event,class FSM>
84	void on_exit(Event const&,FSM& ) {std::cout << "leaving: Playing" << std::endl;}
85
86	// The list of FSM states
87	struct Song1 : public msm::front::state<>
88	{
89	template <class Event,class FSM>
90	void on_entry(Event const&,FSM& ) {std::cout << "starting: First song" << std::endl;}
91	template <class Event,class FSM>
92	void on_exit(Event const&,FSM& ) {std::cout << "finishing: First Song" << std::endl;}
93
94	};
95	struct Song2 : public msm::front::state<>
96	{
97	template <class Event,class FSM>
98	void on_entry(Event const&,FSM& ) {std::cout << "starting: Second song" << std::endl;}
99	template <class Event,class FSM>
100	void on_exit(Event const&,FSM& ) {std::cout << "finishing: Second Song" << std::endl;}
101	};
102	struct Song3 : public msm::front::state<>
103	{
104	template <class Event,class FSM>
105	void on_entry(Event const&,FSM& ) {std::cout << "starting: Third song" << std::endl;}
106	template <class Event,class FSM>
107	void on_exit(Event const&,FSM& ) {std::cout << "finishing: Third Song" << std::endl;}
108	};
109	// the initial state. Must be defined
110	typedef Song1 initial_state;
111	// transition actions
112	void start_next_song(NextSong const&) { std::cout << "Playing::start_next_song\n"; }
113	void start_prev_song(PreviousSong const&) { std::cout << "Playing::start_prev_song\n"; }
114	// guard conditions
115
116	typedef Playing_ pl; // makes transition table cleaner
117	// Transition table for Playing
118	struct transition_table : mpl::vector4<
119	// Start Event Next Action Guard
120	// +---------+-------------+---------+---------------------+----------------------+
121	a_row < Song1 , NextSong , Song2 , &pl::start_next_song >,
122	a_row < Song2 , PreviousSong, Song1 , &pl::start_prev_song >,
123	a_row < Song2 , NextSong , Song3 , &pl::start_next_song >,
124	a_row < Song3 , PreviousSong, Song2 , &pl::start_prev_song >
125	// +---------+-------------+---------+---------------------+----------------------+
126	> {};
127	// Replaces the default no-transition response.
128	template <class FSM,class Event>
129	void no_transition(Event const& e, FSM&,int state)
130	{
131	std::cout << "no transition from state " << state
132	<< " on event " << typeid(e).name() << std::endl;
133	}
134	};
135	// back-end
136	typedef msm::back::state_machine<Playing_> Playing;
137
138
139	// state not defining any entry or exit
140	struct Paused : public msm::front::state<>
141	{
142	};
143
144	// the initial state of the player SM. Must be defined
145	typedef Empty initial_state;
146
147	// transition actions
148	void start_playback(play const&) { std::cout << "player::start_playback\n"; }
149	void open_drawer(open_close const&) { std::cout << "player::open_drawer\n"; }
150	void close_drawer(open_close const&) { std::cout << "player::close_drawer\n"; }
151	void store_cd_info(cd_detected const& cd) {std::cout << "player::store_cd_info\n";}
152	void stop_playback(stop const&) { std::cout << "player::stop_playback\n"; }
153	void pause_playback(pause const&) { std::cout << "player::pause_playback\n"; }
154	void resume_playback(end_pause const&) { std::cout << "player::resume_playback\n"; }
155	void stop_and_open(open_close const&) { std::cout << "player::stop_and_open\n"; }
156	void stopped_again(stop const&){std::cout << "player::stopped_again\n";}
157	// guard conditions
158
159	typedef player_ p; // makes transition table cleaner
160
161	// Transition table for player
162	struct transition_table : mpl::vector<
163	// Start Event Next Action Guard
164	// +---------+-------------+---------+---------------------+----------------------+
165	a_row < Stopped , play , Playing , &p::start_playback >,
166	a_row < Stopped , open_close , Open , &p::open_drawer >,
167	a_row < Stopped , stop , Stopped , &p::stopped_again >,
168	// +---------+-------------+---------+---------------------+----------------------+
169	a_row < Open , open_close , Empty , &p::close_drawer >,
170	// +---------+-------------+---------+---------------------+----------------------+
171	a_row < Empty , open_close , Open , &p::open_drawer >,
172	a_row < Empty , cd_detected , Stopped , &p::store_cd_info >,
173	// +---------+-------------+---------+---------------------+----------------------+
174	a_row < Playing , stop , Stopped , &p::stop_playback >,
175	a_row < Playing , pause , Paused , &p::pause_playback >,
176	a_row < Playing , open_close , Open , &p::stop_and_open >,
177	// +---------+-------------+---------+---------------------+----------------------+
178	a_row < Paused , end_pause , Playing , &p::resume_playback >,
179	a_row < Paused , stop , Stopped , &p::stop_playback >,
180	a_row < Paused , open_close , Open , &p::stop_and_open >
181	// +---------+-------------+---------+---------------------+----------------------+
182	> {};
183
184	// Replaces the default no-transition response.
185	template <class FSM,class Event>
186	void no_transition(Event const& e, FSM&,int state)
187	{
188	std::cout << "no transition from state " << state
189	<< " on event " << typeid(e).name() << std::endl;
190	}
191
192	};
193	// Pick a back-end
194	typedef msm::back::state_machine<player_> player;
195
196	//
197	// Testing utilities.
198	//
199	static char const* const state_names[] = { "Stopped", "Open", "Empty", "Playing", "Paused" };
200
201	void pstate(player const& p)
202	{
203	std::cout << " -> " << state_names[p.current_state()[0]] << std::endl;
204	}
205
206	void test()
207	{
208	player p;
209	// needed to start the highest-level SM. This will call on_entry and mark the start of the SM
210	p.start();
211	// go to Open, call on_exit on Empty, then action, then on_entry on Open
212	p.process_event(open_close()); pstate(p);
213	p.process_event(open_close()); pstate(p);
214	p.process_event(cd_detected("louie, louie"));
215	p.process_event(play());
216
217	// at this point, Play is active
218	// make transition happen inside it. Player has no idea about this event but it's ok.
219	p.process_event(NextSong());pstate(p); //2nd song active
220	p.process_event(NextSong());pstate(p);//3rd song active
221	p.process_event(PreviousSong());pstate(p);//2nd song active
222
223	p.process_event(pause()); pstate(p);
224	// go back to Playing
225	// as you see, it starts back from the original state
226	p.process_event(end_pause()); pstate(p);
227	p.process_event(pause()); pstate(p);
228	p.process_event(stop()); pstate(p);
229	// event leading to the same state
230	p.process_event(stop()); pstate(p);
231	// stop the fsm (call on_exit's, including the submachines)
232	p.process_event(play());
233	std::cout << "stop fsm" << std::endl;
234	p.stop();
235	std::cout << "restart fsm" << std::endl;
236	p.start();
237	}
238	}
239
240	int main()
241	{
242	test();
243	return 0;
244	}