Base class for custom state machine. More...

Inheritance diagram for PIStateMachine< Type >:

Classes
struct	Rule
	Rule of transition between states of machine More...

struct	State
	State of machine More...

Public Types
typedef PIPair< PIString, int >	Condition
	Condition is a pair (string, number)

Public Member Functions
	PIStateMachine (void *_parent=0)
	Constructs an empty state machine.

void	addState (Type value, const PIString &name="", Handler handler=0)
	Add state of machine.

int	statesCount () const
	States count.

void	clearStates ()
	Remove all states.

void	addRule (Type from, Type to, const PIString &condition, Handler handler=0, bool autoTransition=false, bool resetAllConditions=false)
	Add rule of transition.

void	addRule (Type from, Type to, Handler handler, bool autoTransition=false, bool resetAllConditions=false)
	Add rule of transition.

void	addRule (Type from, Type to, const PIStringList &conditions=PIStringList(), Handler handler=0, bool autoTransition=false, bool resetAllConditions=false)
	Add rule of transition.

void	addRule (const Rule &rule)
	Add rule of transition.

int	rulesCount () const
	Rules count.

void	clearRules ()
	Remove all rules.

void	setInitialState (Type value)
	Setup initial state. reset() will set machine state to "value".

bool	switchToState (Type to)
	Try to switch machine state to state "to". More...

void	reset ()
	Reset machine state to initial and clear all conditions.

const State &	currentState () const
	Returns current state of machine.

void	resetConditions ()
	Reset all performed conditions.

void	resetCondition (const PIString &name)
	Reset performed condition with name "name".

void	performCondition (const PIString &name, int times=1)
	Perform condition with name "name" "times" times.

void	performConditions (const PIStringList &names)
	Perform every condition with name from "names" one time.

const PIVector< Condition > &	currentConditions () const
	Returns all current performed conditions.

Public Member Functions inherited from PIObject
	PIObject (const PIString &name=PIString())
	Contructs PIObject with name "name".

PIString	name () const
	Returns object name.

virtual const char *	className () const
	Returns object class name.

bool	debug () const
	Return if debug of this object is active.

void	setName (const PIString &name)
	Set object name.

void	setDebug (bool debug)
	Set object debug active.

const PIMap< PIString, PIVariant > &	properties () const
	Returns properties of the object.

int	propertiesCount () const
	Returns properties count of the object.

PIVariant	property (const PIString &name) const
	Returns property with name "name".

void	setProperty (const PIString &name, const PIVariant &value)
	Set property with name "name" to "value". If there is no such property in object it will be added.

bool	isPropertyExists (const PIString &name) const
	Returns if property with name "name" exists.

Protected Member Functions
virtual void	execution (const State &state)
	Reimplement this function to process current state of machine.

virtual void	transition (const State &from, const State &to)
	Reimplement this function to process switching current state of machine.

Protected Member Functions inherited from PIObject
PIObject *	emitter () const
	Returns PIObject* which has raised an event. This value is correct only in definition of some event handler.

virtual void	propertyChanged (const PIString &name)
	Virtual function executes after property with name "name" has been changed.

Handlers
void	tick ()
	Main function of machine. Execute execution() and check if need to switch state.

void	tick (void *data, int delim)
	Main function of machine. Execute execution() and check if need to switch state.

Additional Inherited Members
Static Public Member Functions inherited from PIObject
static void	piDisconnect (PIObject *src, const PIString &sig)
	Disconnect object "src" from all connections with event name "sig".

static void	piDisconnect (PIObject *src)
	Disconnect object "src" from all connections, i.e. all connections where object "src" is emitter.

static PIObject *	findByName (const PIString &name)
	Returns PIObject* with name "name" or 0, if there is no object found.

Related Functions inherited from PIObject
#define	piCoutObj
	Macro used for conditional (piDebug and PIObject::debug()) output to PICout for subclasses of PIObject.

#define	PIOBJECT(name)
	you should use this macro after class declaration to use EVENT and EVENT_HANDLER and correct piCoutObj output

#define	EVENT_HANDLER0(ret, name) ret name()
	declare event handler "event" with name "name" and return type "ret", ret name()

#define	EVENT_HANDLER1(ret, name, type0, var0) ret name(type0 var0)
	declare event handler "event" with name "name" and return type "ret", ret name(type0 var0)

#define	EVENT_HANDLER2(ret, name, type0, var0, type1, var1) ret name(type0 var0, type1 var1)
	declare event handler "event" with name "name" and return type "ret", ret name(type0 var0, type1 var1)

#define	EVENT_HANDLER3(ret, name, type0, var0, type1, var1, type2, var2) ret name(type0 var0, type1 var1, type2 var2)
	declare event handler "event" with name "name" and return type "ret", ret name(type0 var0, type1 var1, type2 var2)

#define	EVENT_HANDLER4(ret, name, type0, var0, type1, var1, type2, var2, type3, var3) ret name(type0 var0, type1 var1, type2 var2, type3 var3)
	declare event handler "event" with name "name" and return type "ret", ret name(type0 var0, type1 var1, type2 var2, type3 var3)

#define	EVENT_HANDLER EVENT_HANDLER0
	EVENT_HANDLER is synonym of EVENT_HANDLER0.

#define	EVENT_VHANDLER0(ret, name) virtual ret name()
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name()

#define	EVENT_VHANDLER1(ret, name, type0, var0) virtual ret name(type0 var0)
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name(type0 var0)

#define	EVENT_VHANDLER2(ret, name, type0, var0, type1, var1) virtual ret name(type0 var0, type1 var1)
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name(type0 var0, type1 var1)

#define	EVENT_VHANDLER3(ret, name, type0, var0, type1, var1, type2, var2) virtual ret name(type0 var0, type1 var1, type2 var2)
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name(type0 var0, type1 var1, type2 var2)

#define	EVENT_VHANDLER4(ret, name, type0, var0, type1, var1, type2, var2, type3, var3) virtual ret name(type0 var0, type1 var1, type2 var2, type3 var3)
	declare virtual event handler "event" with name "name" and return type "ret", virtual ret name(type0 var0, type1 var1, type2 var2, type3 var3)

#define	EVENT_VHANDLER EVENT_VHANDLER0
	EVENT_VHANDLER is synonym of EVENT_VHANDLER0.

#define	EVENT0(name) void name();
	declare event "event" with name "name", void name();

#define	EVENT1(name, type0, var0) void name(type0 var0);
	declare event "event" with name "name", void name(type0 var0);

#define	EVENT2(name, type0, var0, type1, var1) void name(type0 var0, type1 var1);
	declare event "event" with name "name", void name(type0 var0, type1 var1);

#define	EVENT3(name, type0, var0, type1, var1, type2, var2) void name(type0 var0, type1 var1, type2 var2);
	declare event "event" with name "name", void name(type0 var0, type1 var1, type2 var2);

#define	EVENT4(name, type0, var0, type1, var1, type2, var2, type3, var3) void name(type0 var0, type1 var1, type2 var2, type3 var3);
	declare event "event" with name "name", void name(type0 var0, type1 var1, type2 var2, type3 var3);

#define	EVENT EVENT0
	EVENT is synonym of EVENT0.

#define	CONNECT0(ret, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists

#define	CONNECT1(ret, type0, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists

#define	CONNECT2(ret, type0, type1, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists

#define	CONNECT3(ret, type0, type1, type2, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists

#define	CONNECT4(ret, type0, type1, type2, type3, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" with check of event and handler exists

#define	CONNECT CONNECT0
	CONNECT is synonym of CONNECT0.

#define	WEAK_CONNECT0(ret, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists

#define	WEAK_CONNECT1(ret, type0, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists

#define	WEAK_CONNECT2(ret, type0, type1, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists

#define	WEAK_CONNECT3(ret, type0, type1, type2, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists

#define	WEAK_CONNECT4(ret, type0, type1, type2, type3, src, event, dest, handler)
	connect event "event" from object "src" to event handler "handler" with return type "ret" from object "dest" without check of event exists

#define	WEAK_CONNECT WEAK_CONNECT0
	WEAK_CONNECT is synonym of WEAK_CONNECT0.

#define	DISCONNECT0(ret, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT1(ret, type0, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT2(ret, type0, type1, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT3(ret, type0, type1, type2, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT4(ret, type0, type1, type2, type3, src, event, dest, handler)
	piDisconnect event "event" from object "src" from event handler "handler" with return type "ret" from object "dest"

#define	DISCONNECT DISCONNECT0
	DISCONNECT is synonym of DISCONNECT0.

#define	HANDLER(handler)
	Returns pointer to events handler "handler".

Detailed Description

template<typename Type = int>
class PIStateMachine< Type >

Base class for custom state machine.

Synopsis

This class provide functionality of state machine. You should inherit from this class, implement execution() and transition() functions, set rules and periodically call tick() function to proper work of machine.

Prepare for work

State machine operates with "state", "rule" and "condition".

"State" is some class (by default int), associated name and optional "handler" - pointer to function executed on every tick();
"Rule" define rule of transition from one machine state to other. It is also has optional "handler";
"Condition" is a part of rule and define possibility of transition.

First of all you should define states of your machine by function addState(). Then you should define transition rules for machine by function addRule(). Finally you can set initial state by function setInitialState() and provide periodically execution of function tick().

Principle of work

At any time the state machine is in some state. You can ask machine to enter in new state by function switchToState(). If all conditions done machine switch it state immediately, else machine remember request and will be try switch to the new state every tick. Successfull state switching execute function transition(), every tick execute function execution() with current state. On successfull transition if rule "handler" is not null it execute. Every tick() if current state "handler" is not null it execute.

Conditions

Each rule has transition condition. Condition is array of pairs (string, number). It means that every condition by name "string" should be performed as least "number" times. Empty condition always permits transition.

State machine have current performed conditions. You can read this conditions by function currentConditions() and perform new conditions by functions performCondition() and performConditions(). Currend conditions can de erased by function resetConditions().

Example

This is simple example demonstrates all features:

#include "pip.h"
enum Mode {Start, Manual, Auto, Finish, End};
class Machine: public PIStateMachine<Mode> {
    PIOBJECT(Machine)
public:
    Machine() {
        addState(Start, "start", HANDLER(startFunc));
        addState(Manual, "manual", HANDLER(manualFunc));
        addState(Auto, "auto", HANDLER(autoFunc));
        addState(Finish, "finish", HANDLER(finishFunc));
        addState(End, "end", HANDLER(endFunc));
        
        addRule(Start, Manual, "init_ok", HANDLER(beginManualFunc));
        addRule(Start, Auto, "init_ok", HANDLER(beginAutoFunc));
        addRule(Manual, Auto, HANDLER(manualToAutoFunc));
        addRule(Auto, Manual, HANDLER(autoToManualFunc));
        addRule(Manual, Finish);
        addRule(Auto, Finish);
        Rule r(Finish, End);
        r.addCondition("finish_0_ok");
        r.addCondition("finish_1_ok", 2);
        addRule(r);
        
        setInitialState(Start);
        
        CONNECT2(void, void*, int, &timer, timeout, this, tick);
        timer.start(500);
    }
    virtual void execution(const State & state) {
        piCout << "performed conditions:" << currentConditions();
    }
    virtual void transition(const State & from, const State & to) {
        piCout << "switch from" << from.name << "to" << to.name << "state";
    }
    
    EVENT_HANDLER(void, startFunc) {piCout << "start function";}
    EVENT_HANDLER(void, manualFunc) {piCout << "manual function";}
    EVENT_HANDLER(void, autoFunc) {piCout << "auto function";}
    EVENT_HANDLER(void, finishFunc) {piCout << "finish function";}
    EVENT_HANDLER(void, endFunc) {piCout << "end function";}
    EVENT_HANDLER(void, beginManualFunc) {piCout << "begin manual function";}
    EVENT_HANDLER(void, beginAutoFunc) {piCout << "begin auto function";}
    EVENT_HANDLER(void, autoToManualFunc) {piCout << "switch from auto to manual function";}
    EVENT_HANDLER(void, manualToAutoFunc) {piCout << "switch from manual to auto function";}
    
    PITimer timer;
};
Machine machine;
void key_event(char key, void*) {
    switch (key) {
    case 's': machine.switchToState(Start); break;
    case 'm': machine.switchToState(Manual); break;
    case 'a': machine.switchToState(Auto); break;
    case 'f': machine.switchToState(Finish); break;
    case 'e': machine.switchToState(End); break;
    case '1': machine.performCondition("init_ok"); break;
    case '2': machine.performCondition("finish_0_ok"); break;
    case '3': machine.performCondition("finish_1_ok"); break;
    case 'r': machine.resetConditions(); break;
    case 'R': machine.reset(); break;
    }
}
int main(int argc, char * argv[]) {
    PIKbdListener kbd(key_event);
    kbd.enableExitCapture();
    WAIT_FOR_EXIT
};

Member Function Documentation

template<typename Type = int>

bool PIStateMachine< Type >::switchToState ( Type to )

inline

Try to switch machine state to state "to".

If there is rule of transition exists and this rule conditions is performed then machine switched to new state immediately. Otherwise machine will be try to enter to new state every tick().

Returns: true if state switched immediately, otherwise false

Classes

Public Types

Public Member Functions

Protected Member Functions

Handlers

Additional Inherited Members