A Finite-state machine. More...

#include <fsm.h>

Inheritance diagram for zth::Fsm< State_, Input_, FsmImpl_ >:

Public Types
typedef choose_type< FsmImpl_, Fsm >::type	FsmImpl

typedef State_	State

typedef Input_	Input

typedef FsmCompiler< FsmImpl >	Compiler

typedef FsmDescription< FsmImpl >	Description[]

Public Member Functions
	Fsm (Compiler const &compiler, char const *name="FSM")

	Fsm (Description description, char const *name="FSM")

virtual	~Fsm ()

State const &	state () const

Timestamp const &	t () const

TimeInterval	dt () const

State const &	next () const

void	reset ()

bool	entry () const

bool	exit () const

bool	lockstep () const
	Check if lockstep mode is enabled. More...

void	setLockstep (bool enable)
	Enable/disable lockstep mode. More...

bool	guardLock ()
	Check if a lock was requested while running in lockstep mode. More...

bool	guardStep ()
	Check if a step was requested while paused in lockstep mode. More...

void	step ()
	Allow the Fsm to proceed one step, if in lockstep mode. More...

void	input (Input i)

bool	clearInput (Input i)

void	clearInputs ()

void	setInputsCapacity (size_t capacity)

bool	hasInput (Input i) const

TimeInterval	eval (bool alwaysDoCallback=false)

void	run ()

void	trigger ()

Public Member Functions inherited from zth::UniqueID< Fsm< void, void, void > >
	UniqueID (UniqueID const &)=delete

	UniqueID (UniqueID &&u) noexcept

	UniqueID (string const &name)

	UniqueID (string &&name)

	UniqueID (char const *name=nullptr)

UniqueID &	operator= (UniqueID const &)=delete

UniqueID &	operator= (UniqueID &&u) noexcept

virtual	~UniqueID ()=default

void const *	normptr () const noexcept

uint64_t	id () const noexcept

string const &	name () const noexcept

void	setName (string const &name)

void	setName (char const *name)

void	setName (string &&name)

virtual char const *	id_str () const override

Protected Types
enum	EvalState { evalCompile , evalInit , evalReset , evalIdle , evalState , evalRecurse }

enum	Lockstep { lockstepNormal , lockstepLock , lockstepStep , lockstepSteppingNext , lockstepStepping }

typedef FsmDescription< FsmImpl > const *	StateAddr

Protected Member Functions
virtual void	callback ()=0
	This function is called when the FSM has to execute the code belonging by the current state. More...

Protected Member Functions inherited from zth::UniqueIDBase
virtual	~UniqueIDBase ()=default

Additional Inherited Members
Static Public Member Functions inherited from zth::UniqueID< Fsm< void, void, void > >
static uint64_t	getID () noexcept

Detailed Description

template<typename State_, typename Input_ = int, typename FsmImpl_ = void>
class zth::Fsm< State_, Input_, FsmImpl_ >

A Finite-state machine.

Template Parameters

State_	the type of a state, which can be anything, as long as it is default-constructable and assignable, and comparable with `std:less`.
Input_	the type of inputs, as used by Fsm::input(), which has the same type requirements as `State_`.
FsmImpl_	the actual subclass type of `Fsm`, which is used for the zth::FsmDescription. So, if you derive from Fsm, pass your class to `FsmImpl_`, such that every guard gets your actual `Fsm` type reference. When `void`, assume that there is no subclass, and just use the `Fsm` reference instead.

Definition at line 304 of file fsm.h.

Member Typedef Documentation

◆ Compiler

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

typedef FsmCompiler<FsmImpl> zth::Fsm< State_, Input_, FsmImpl_ >::Compiler

Definition at line 310 of file fsm.h.

◆ Description

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

typedef FsmDescription<FsmImpl> zth::Fsm< State_, Input_, FsmImpl_ >::Description[]

Definition at line 311 of file fsm.h.

◆ FsmImpl

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

typedef choose_type<FsmImpl_, Fsm>::type zth::Fsm< State_, Input_, FsmImpl_ >::FsmImpl

Definition at line 307 of file fsm.h.

◆ Input

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

typedef Input_ zth::Fsm< State_, Input_, FsmImpl_ >::Input

Definition at line 309 of file fsm.h.

◆ State

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

typedef State_ zth::Fsm< State_, Input_, FsmImpl_ >::State

Definition at line 308 of file fsm.h.

◆ StateAddr

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

typedef FsmDescription<FsmImpl> const* zth::Fsm< State_, Input_, FsmImpl_ >::StateAddr

protected

Definition at line 315 of file fsm.h.

Member Enumeration Documentation

◆ EvalState

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

enum zth::Fsm::EvalState

protected

Enumerator
evalCompile
evalInit
evalReset
evalIdle
evalState
evalRecurse

Definition at line 314 of file fsm.h.

◆ Lockstep

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

enum zth::Fsm::Lockstep

protected

Enumerator
lockstepNormal
lockstepLock
lockstepStep
lockstepSteppingNext
lockstepStepping

Definition at line 317 of file fsm.h.

Constructor & Destructor Documentation

◆ Fsm() [1/2]

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

zth::Fsm< State_, Input_, FsmImpl_ >::Fsm	(	Compiler const &	compiler,
		char const *	name = `"FSM"`
	)

inlineexplicit

Definition at line 326 of file fsm.h.

◆ Fsm() [2/2]

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

zth::Fsm< State_, Input_, FsmImpl_ >::Fsm	(	Description	description,
		char const *	name = `"FSM"`
	)

inlineexplicit

Definition at line 337 of file fsm.h.

◆ ~Fsm()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

virtual zth::Fsm< State_, Input_, FsmImpl_ >::~Fsm ( )

inlinevirtual

Definition at line 344 of file fsm.h.

Member Function Documentation

◆ callback()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

virtual void zth::Fsm< State_, Input_, FsmImpl_ >::callback ( )

protectedpure virtual

This function is called when the FSM has to execute the code belonging by the current state.

It is called upon entry and exit of a state, and arbitrary times during a state.

Implemented in zth::FsmCallback< State_, void, Input_, FsmImpl_ >, and zth::FsmCallback< State_, CallbackArg_, Input_, FsmImpl_ >.

◆ clearInput()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

bool zth::Fsm< State_, Input_, FsmImpl_ >::clearInput ( Input i )

inline

Definition at line 527 of file fsm.h.

◆ clearInputs()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

void zth::Fsm< State_, Input_, FsmImpl_ >::clearInputs ( )

inline

Definition at line 538 of file fsm.h.

◆ dt()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

TimeInterval zth::Fsm< State_, Input_, FsmImpl_ >::dt ( ) const

inline

Definition at line 365 of file fsm.h.

◆ entry()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

bool zth::Fsm< State_, Input_, FsmImpl_ >::entry ( ) const

inline

Definition at line 405 of file fsm.h.

◆ eval()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

TimeInterval zth::Fsm< State_, Input_, FsmImpl_ >::eval ( bool alwaysDoCallback = false )

inline

Definition at line 563 of file fsm.h.

◆ exit()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

bool zth::Fsm< State_, Input_, FsmImpl_ >::exit ( ) const

inline

Definition at line 410 of file fsm.h.

◆ guardLock()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

bool zth::Fsm< State_, Input_, FsmImpl_ >::guardLock ( )

inline

Check if a lock was requested while running in lockstep mode.

Returns: true if the Fsm is to be paused

See also: setLockstep()

Definition at line 477 of file fsm.h.

◆ guardStep()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

bool zth::Fsm< State_, Input_, FsmImpl_ >::guardStep ( )

inline

Check if a step was requested while paused in lockstep mode.

Returns: true if the Fsm may continue

See also: setLockstep()

Definition at line 493 of file fsm.h.

◆ hasInput()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

bool zth::Fsm< State_, Input_, FsmImpl_ >::hasInput ( Input i ) const

inline

Definition at line 555 of file fsm.h.

◆ input()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

void zth::Fsm< State_, Input_, FsmImpl_ >::input ( Input i )

inline

Definition at line 521 of file fsm.h.

◆ lockstep()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

bool zth::Fsm< State_, Input_, FsmImpl_ >::lockstep ( ) const

inline

Check if lockstep mode is enabled.

Definition at line 418 of file fsm.h.

◆ next()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

State const& zth::Fsm< State_, Input_, FsmImpl_ >::next ( ) const

inline

Definition at line 370 of file fsm.h.

◆ reset()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

void zth::Fsm< State_, Input_, FsmImpl_ >::reset ( )

inline

Definition at line 385 of file fsm.h.

◆ run()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

void zth::Fsm< State_, Input_, FsmImpl_ >::run ( )

inline

Definition at line 608 of file fsm.h.

◆ setInputsCapacity()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

void zth::Fsm< State_, Input_, FsmImpl_ >::setInputsCapacity ( size_t capacity )

inline

Definition at line 543 of file fsm.h.

◆ setLockstep()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

void zth::Fsm< State_, Input_, FsmImpl_ >::setLockstep ( bool enable )

inline

Enable/disable lockstep mode.

Assume the following FSM:

* +--> A ---+
* |         |
* +--- B <--+
*

Normally, the transitions have guards that determine if the Fsm is allowed to continue. In lockstep mode, one add special states where the Fsm can wait for an explicit input. For example, if such explicit input is required before continuing back to A:

* +--> A ---+
* |         |
* +--- B <--+
*     ^ \
*    /   \
*   +- C <+
*

In this Fsm, once B is reached, the Fsm may go to the stalled state C, wait for an explicit input, go back to B and proceed to A. To implement this, add a guard that checks guardLock() at entry of B. If it returns true, proceed to C. In C, add a guard that checks guardStep(). If it returns true, proceed back to B. Any guardLock() guards are ignored until state B is left. If the expected explicit input was received, call step().

Definition at line 456 of file fsm.h.

◆ state()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

State const& zth::Fsm< State_, Input_, FsmImpl_ >::state ( ) const

inline

Definition at line 346 of file fsm.h.

◆ step()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

void zth::Fsm< State_, Input_, FsmImpl_ >::step ( )

inline

Allow the Fsm to proceed one step, if in lockstep mode.

See also: setLockstep()

Definition at line 510 of file fsm.h.

◆ t()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

Timestamp const& zth::Fsm< State_, Input_, FsmImpl_ >::t ( ) const

inline

Definition at line 360 of file fsm.h.

◆ trigger()

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

void zth::Fsm< State_, Input_, FsmImpl_ >::trigger ( )

inline

Definition at line 632 of file fsm.h.

Member Data Documentation

◆ m_compiledDescription

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

FsmDescription<FsmImpl> const* zth::Fsm< State_, Input_, FsmImpl_ >::m_compiledDescription

Definition at line 711 of file fsm.h.

◆ m_compiler

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

Compiler const* zth::Fsm< State_, Input_, FsmImpl_ >::m_compiler

Definition at line 710 of file fsm.h.

◆ m_description

template<typename State_ , typename Input_ = int, typename FsmImpl_ = void>

FsmDescription<FsmImpl>* zth::Fsm< State_, Input_, FsmImpl_ >::m_description

Definition at line 709 of file fsm.h.

The documentation for this class was generated from the following file:

include/libzth/fsm.h

Public Types

Public Member Functions

Protected Types

Protected Member Functions

Additional Inherited Members

Detailed Description

template<typename State_, typename Input_ = int, typename FsmImpl_ = void> class zth::Fsm< State_, Input_, FsmImpl_ >

Member Typedef Documentation

◆ Compiler

◆ Description

◆ FsmImpl

◆ Input

◆ State

◆ StateAddr

Member Enumeration Documentation

◆ EvalState

◆ Lockstep

Constructor & Destructor Documentation

◆ Fsm() [1/2]

◆ Fsm() [2/2]

◆ ~Fsm()

Member Function Documentation

◆ callback()

◆ clearInput()

◆ clearInputs()

◆ dt()

◆ entry()

◆ eval()

◆ exit()

◆ guardLock()

◆ guardStep()

◆ hasInput()

◆ input()

◆ lockstep()

◆ next()

◆ reset()

◆ run()

◆ setInputsCapacity()

◆ setLockstep()

◆ state()

◆ step()

◆ t()

◆ trigger()

Member Data Documentation

◆ m_compiledDescription

◆ m_compiler

◆ m_description

template<typename State_, typename Input_ = int, typename FsmImpl_ = void>
class zth::Fsm< State_, Input_, FsmImpl_ >