RollbackState Class Reference

#include <RollbackState.h>

Inheritance diagram for RollbackState:

Collaboration diagram for RollbackState:

Public Types
using	ForwardAction = std::function< bool()>
	Forward action - returns true on success.
using	RollbackAction = std::function< void()>
	Rollback action - executed on forward failure.
Public Types inherited from QGCAbstractState
using	EntryCallback = std::function< void()>
using	ExitCallback = std::function< void()>
using	EventHandler = std::function< bool(QEvent *)>

Signals
void	forwardSucceeded ()
	Emitted when forward action succeeds.
void	forwardFailed ()
	Emitted when forward action fails (before rollback)
void	rollingBack ()
	Emitted when rollback starts.
void	rollbackComplete ()
	Emitted when rollback completes.
Signals inherited from QGCAbstractState
void	advance ()
void	error ()

Public Member Functions
	RollbackState (const QString &stateName, QState *parent, ForwardAction forwardAction, RollbackAction rollbackAction)
bool	wasRolledBack () const
	Check if rollback was executed.
bool	rollbackSucceeded () const
	Check if rollback succeeded (only valid if wasRolledBack() is true)
Public Member Functions inherited from QGCState
	QGCState (const QString &stateName, QState *parentState)
template<typename PointerToMemberFunction >
QSignalTransition *	addThisTransition (PointerToMemberFunction signal, QAbstractState *target)
	Simpler version of QState::addTransition which assumes the sender is this.
void	setLocalErrorState (QAbstractState *errorState)
QAbstractState *	localErrorState () const
	Get the per-state error state (nullptr if using global)
void	setProperty (QObject *object, const char *name, const QVariant &value)
void	setEnabled (QObject *object, bool enabled)
	Convenience overload for setting enabled state on widgets/controls.
void	setVisible (QObject *object, bool visible)
	Convenience overload for setting visible state on widgets/controls.
Public Member Functions inherited from QGCAbstractState
	QGCAbstractState (const QString &stateName, QState *parent)
QGCStateMachine *	machine () const
Vehicle *	vehicle () const
QString	stateName () const
class StateContext *	context () const
void	setOnEntry (EntryCallback callback)
	Set a callback to be invoked when the state is entered.
void	setOnExit (ExitCallback callback)
	Set a callback to be invoked when the state is exited.
void	setCallbacks (EntryCallback onEntry, ExitCallback onExit=nullptr)
	Set both entry and exit callbacks.
void	setEventHandler (EventHandler handler)
	Set a custom event handler for this state.

Protected Member Functions
void	onEnter () override
	Override to perform actions on state entry.
Protected Member Functions inherited from QGCAbstractState
virtual void	onLeave ()
	Override to perform actions on state exit.
void	onEntry (QEvent *event) override
void	onExit (QEvent *event) override
bool	event (QEvent *event) override

Detailed Description

A state that executes an action with automatic rollback on failure.

If the forward action fails, the rollback action is executed before emitting the error() signal. This provides transaction-like semantics.

Example usage:

auto* state = new RollbackState("UpdateFirmware", &machine,
    []() { return flashFirmware(); },      // Forward action
    []() { restorePreviousFirmware(); }    // Rollback action (void)
);
 
state->addTransition(state, &RollbackState::advance, successState);
state->addTransition(state, &RollbackState::error, errorState);

Definition at line 22 of file RollbackState.h.

Member Typedef Documentation

ForwardAction

using RollbackState::ForwardAction = std::function<bool()>

Forward action - returns true on success.

Definition at line 29 of file RollbackState.h.

RollbackAction

using RollbackState::RollbackAction = std::function<void()>

Rollback action - executed on forward failure.

Definition at line 32 of file RollbackState.h.

Constructor & Destructor Documentation

RollbackState()

RollbackState::RollbackState	(	const QString &	stateName,
		QState *	parent,
		ForwardAction	forwardAction,
		RollbackAction	rollbackAction
	)

Parameters

stateName	Name for logging
parent	Parent state
forwardAction	Action to execute (returns true on success)
rollbackAction	Action to execute on failure (cleanup/restore)

Definition at line 4 of file RollbackState.cc.

Member Function Documentation

forwardFailed

void RollbackState::forwardFailed ( )

signal

Emitted when forward action fails (before rollback)

Referenced by onEnter().

forwardSucceeded

void RollbackState::forwardSucceeded ( )

signal

Emitted when forward action succeeds.

Referenced by onEnter().

onEnter()

void RollbackState::onEnter ( )

overrideprotectedvirtual

Override to perform actions on state entry.

Reimplemented from QGCAbstractState.

Definition at line 12 of file RollbackState.cc.

References QGCAbstractState::advance(), QGCAbstractState::error(), forwardFailed(), forwardSucceeded(), rollbackComplete(), rollingBack(), and QGCAbstractState::stateName().

rollbackComplete

void RollbackState::rollbackComplete ( )

signal

Emitted when rollback completes.

Referenced by onEnter().

rollbackSucceeded()

bool RollbackState::rollbackSucceeded ( ) const

inline

Check if rollback succeeded (only valid if wasRolledBack() is true)

Definition at line 45 of file RollbackState.h.

rollingBack

void RollbackState::rollingBack ( )

signal

Emitted when rollback starts.

Referenced by onEnter().

wasRolledBack()

bool RollbackState::wasRolledBack ( ) const

inline

Check if rollback was executed.

Definition at line 42 of file RollbackState.h.

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

• src/Utilities/StateMachine/States/RollbackState.h
• src/Utilities/StateMachine/States/RollbackState.cc