1 #include <vector>
2 #include <iostream>
3 // back-end
4 #include <boost/msm/back/state_machine.hpp>
5 // header for support of circular_buffer
6 #include <boost/msm/back/queue_container_circular.hpp>
7 //front-end
8 #include <boost/msm/front/state_machine_def.hpp>
9 // functors
10 #include <boost/msm/front/functor_row.hpp>
11 #include <boost/msm/front/euml/common.hpp>
12 // for And_ operator
13 #include <boost/msm/front/euml/operator.hpp>
14
15 using namespace std;
16 namespace msm = boost::msm;
17 namespace mpl = boost::mpl;
18 using namespace msm::front;
19 // for And_ operator
20 using namespace msm::front::euml;
21
22 namespace // Concrete FSM implementation
23 {
24 // events
25 struct play {};
26 struct end_pause {};
27 struct stop {};
28 struct pause {};
29 struct open_close {};
30
31 // A "complicated" event type that carries some data.
32 enum DiskTypeEnum
33 {
34 DISK_CD=0,
35 DISK_DVD=1
36 };
37 struct cd_detected
38 {
cd_detected__anonc47571310111::cd_detected39 cd_detected(std::string name, DiskTypeEnum diskType)
40 : name(name),
41 disc_type(diskType)
42 {}
43
44 std::string name;
45 DiskTypeEnum disc_type;
46 };
47
48 // front-end: define the FSM structure
49 struct player_ : public msm::front::state_machine_def<player_>
50 {
51 // The list of FSM states
52 struct Empty : public msm::front::state<>
53 {
54 // every (optional) entry/exit methods get the event passed.
55 template <class Event,class FSM>
on_entry__anonc47571310111::player_::Empty56 void on_entry(Event const&,FSM& ) {std::cout << "entering: Empty" << std::endl;}
57 template <class Event,class FSM>
on_exit__anonc47571310111::player_::Empty58 void on_exit(Event const&,FSM& ) {std::cout << "leaving: Empty" << std::endl;}
59 };
60 struct Open : public msm::front::state<>
61 {
62 template <class Event,class FSM>
on_entry__anonc47571310111::player_::Open63 void on_entry(Event const& ,FSM&) {std::cout << "entering: Open" << std::endl;}
64 template <class Event,class FSM>
on_exit__anonc47571310111::player_::Open65 void on_exit(Event const&,FSM& ) {std::cout << "leaving: Open" << std::endl;}
66 };
67
68 struct Stopped : public msm::front::state<>
69 {
70 // when stopped, the CD is loaded
71 template <class Event,class FSM>
on_entry__anonc47571310111::player_::Stopped72 void on_entry(Event const& ,FSM&) {std::cout << "entering: Stopped" << std::endl;}
73 template <class Event,class FSM>
on_exit__anonc47571310111::player_::Stopped74 void on_exit(Event const&,FSM& ) {std::cout << "leaving: Stopped" << std::endl;}
75 };
76
77 struct Playing : public msm::front::state<>
78 {
79 template <class Event,class FSM>
on_entry__anonc47571310111::player_::Playing80 void on_entry(Event const&,FSM& ) {std::cout << "entering: Playing" << std::endl;}
81 template <class Event,class FSM>
on_exit__anonc47571310111::player_::Playing82 void on_exit(Event const&,FSM& ) {std::cout << "leaving: Playing" << std::endl;}
83 };
84
85 // state not defining any entry or exit
86 struct Paused : public msm::front::state<>
87 {
88 };
89
90 // the initial state of the player SM. Must be defined
91 typedef Empty initial_state;
92
93 // transition actions
94 // as the functors are generic on events, fsm and source/target state,
95 // you can reuse them in another machine if you wish
96 struct TestFct
97 {
98 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::TestFct99 void operator()(EVT const&, FSM&,SourceState& ,TargetState& )
100 {
101 cout << "transition with event:" << typeid(EVT).name() << endl;
102 }
103 };
104 struct start_playback
105 {
106 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::start_playback107 void operator()(EVT const& ,FSM& ,SourceState& ,TargetState& )
108 {
109 cout << "player::start_playback" << endl;
110 }
111 };
112 struct open_drawer
113 {
114 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::open_drawer115 void operator()(EVT const& ,FSM& ,SourceState& ,TargetState& )
116 {
117 cout << "player::open_drawer" << endl;
118 }
119 };
120 struct close_drawer
121 {
122 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::close_drawer123 void operator()(EVT const& ,FSM& ,SourceState& ,TargetState& )
124 {
125 cout << "player::close_drawer" << endl;
126 }
127 };
128 struct store_cd_info
129 {
130 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::store_cd_info131 void operator()(EVT const&,FSM& fsm ,SourceState& ,TargetState& )
132 {
133 cout << "player::store_cd_info" << endl;
134 fsm.process_event(play());
135 }
136 };
137 struct stop_playback
138 {
139 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::stop_playback140 void operator()(EVT const& ,FSM& ,SourceState& ,TargetState& )
141 {
142 cout << "player::stop_playback" << endl;
143 }
144 };
145 struct pause_playback
146 {
147 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::pause_playback148 void operator()(EVT const& ,FSM& ,SourceState& ,TargetState& )
149 {
150 cout << "player::pause_playback" << endl;
151 }
152 };
153 struct resume_playback
154 {
155 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::resume_playback156 void operator()(EVT const& ,FSM& ,SourceState& ,TargetState& )
157 {
158 cout << "player::resume_playback" << endl;
159 }
160 };
161 struct stop_and_open
162 {
163 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::stop_and_open164 void operator()(EVT const& ,FSM& ,SourceState& ,TargetState& )
165 {
166 cout << "player::stop_and_open" << endl;
167 }
168 };
169 struct stopped_again
170 {
171 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::stopped_again172 void operator()(EVT const& ,FSM& ,SourceState& ,TargetState& )
173 {
174 cout << "player::stopped_again" << endl;
175 }
176 };
177 // guard conditions
178 struct DummyGuard
179 {
180 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::DummyGuard181 bool operator()(EVT const& evt,FSM& fsm,SourceState& src,TargetState& tgt)
182 {
183 return true;
184 }
185 };
186 struct good_disk_format
187 {
188 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::good_disk_format189 bool operator()(EVT const& evt ,FSM&,SourceState& ,TargetState& )
190 {
191 // to test a guard condition, let's say we understand only CDs, not DVD
192 if (evt.disc_type != DISK_CD)
193 {
194 std::cout << "wrong disk, sorry" << std::endl;
195 return false;
196 }
197 return true;
198 }
199 };
200 struct always_true
201 {
202 template <class EVT,class FSM,class SourceState,class TargetState>
operator ()__anonc47571310111::player_::always_true203 bool operator()(EVT const& evt ,FSM&,SourceState& ,TargetState& )
204 {
205 return true;
206 }
207 };
208 // we want to define one row with the classic look.
auto_start__anonc47571310111::player_209 bool auto_start(cd_detected const& evt)
210 {
211 return false;
212 }
213
214 typedef player_ p; // makes transition table cleaner
215
216 // Transition table for player
217 struct transition_table : mpl::vector<
218 // Start Event Next Action Guard
219 // +---------+-------------+---------+---------------------------+----------------------+
220 Row < Stopped , play , Playing , ActionSequence_
221 <mpl::vector<
222 TestFct,start_playback> >
223 , DummyGuard >,
224 Row < Stopped , open_close , Open , open_drawer , none >,
225 Row < Stopped , stop , Stopped , none , none >,
226 // +---------+-------------+---------+---------------------------+----------------------+
227 Row < Open , open_close , Empty , close_drawer , none >,
228 // +---------+-------------+---------+---------------------------+----------------------+
229 Row < Empty , open_close , Open , open_drawer , none >,
230 Row < Empty , cd_detected , Stopped , store_cd_info , And_<good_disk_format,
231 always_true> >,
232 // we here also mix with some "classical row"
233 g_row < Empty , cd_detected , Playing , &p::auto_start >,
234 // +---------+-------------+---------+---------------------------+----------------------+
235 Row < Playing , stop , Stopped , stop_playback , none >,
236 Row < Playing , pause , Paused , pause_playback , none >,
237 Row < Playing , open_close , Open , stop_and_open , none >,
238 // +---------+-------------+---------+---------------------------+----------------------+
239 Row < Paused , end_pause , Playing , resume_playback , none >,
240 Row < Paused , stop , Stopped , stop_playback , none >,
241 Row < Paused , open_close , Open , stop_and_open , none >
242 // +---------+-------------+---------+---------------------------+----------------------+
243 > {};
244 // Replaces the default no-transition response.
245 template <class FSM,class Event>
no_transition__anonc47571310111::player_246 void no_transition(Event const& e, FSM&,int state)
247 {
248 std::cout << "no transition from state " << state
249 << " on event " << typeid(e).name() << std::endl;
250 }
251 };
252 // Pick a back-end
253 typedef msm::back::state_machine<player_, msm::back::queue_container_circular> player;
254
255 //
256 // Testing utilities.
257 //
258 static char const* const state_names[] = { "Stopped", "Open", "Empty", "Playing", "Paused" };
pstate(player const & p)259 void pstate(player const& p)
260 {
261 std::cout << " -> " << state_names[p.current_state()[0]] << std::endl;
262 }
263
test()264 void test()
265 {
266 player p;
267 // we get the message queue and limit it to capacity 1
268 // get_message_queue returns the queue container (in this case circular_buffer)
269 p.get_message_queue().set_capacity(1);
270 // needed to start the highest-level SM. This will call on_entry and mark the start of the SM
271 p.start();
272 // go to Open, call on_exit on Empty, then action, then on_entry on Open
273 p.process_event(open_close()); pstate(p);
274 p.process_event(open_close()); pstate(p);
275 // will be rejected, wrong disk type
276 p.process_event(
277 cd_detected("louie, louie",DISK_DVD)); pstate(p);
278 p.process_event(
279 cd_detected("louie, louie",DISK_CD)); pstate(p);
280 // no need to call play() as the previous event does it in its action method
281 //p.process_event(play());
282
283 // at this point, Play is active
284 p.process_event(pause()); pstate(p);
285 // go back to Playing
286 p.process_event(end_pause()); pstate(p);
287 p.process_event(pause()); pstate(p);
288 p.process_event(stop()); pstate(p);
289 // event leading to the same state
290 // no action method called as it is not present in the transition table
291 p.process_event(stop()); pstate(p);
292 }
293 }
294
main()295 int main()
296 {
297 test();
298 return 0;
299 }
300