1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
|
// 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(region2_evt)
// 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
// state not defining any entry or exit
BOOST_MSM_EUML_STATE((),Paused)
BOOST_MSM_EUML_STATE(( Empty_Entry,Empty_Exit ),Empty)
BOOST_MSM_EUML_STATE(( Open_Entry,Open_Exit ),Open)
BOOST_MSM_EUML_STATE(( Stopped_Entry,Stopped_Exit ),Stopped)
// Playing is now a state machine itself.
// It has 5 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)
BOOST_MSM_EUML_STATE(( Region2State1_Entry,Region2State1_Exit ),Region2State1)
BOOST_MSM_EUML_STATE(( Region2State2_Entry,Region2State2_Exit ),Region2State2)
// 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,
Region2State2 == Region2State1 + region2_evt
// +------------------------------------------------------------------------------+
),playing_transition_table )
BOOST_MSM_EUML_DECLARE_STATE_MACHINE( (playing_transition_table, //STT
init_ << Song1 << Region2State1 // Init State
),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
// +------------------------------------------------------------------------------+
),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", "Paused", "Open", "Empty", "Playing" };
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();
// note that we write open_close and not open_close(), like usual. Both are possible with eUML, but
// you now have less to type.
// 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);
// 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
// at this point, Play is 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 none is defined in the transition table
p.process_event(stop); pstate(p);
}
}
int main()
{
test();
return 0;
}
|
