Handles getting input from a specific input device using libevdev. More...

#include <EvdevInput.hpp>

Inheritance diagram for duds::os::linux::EvdevInput:

Collaboration diagram for duds::os::linux::EvdevInput:

Public Member Functions
	EvdevInput ()
	Constructs an EvdevInput object without opening a device file. More...

	EvdevInput (const std::string &path)
	Creates a EvdevInput object that will read input from the given device file. More...

	EvdevInput (EvdevInput &&old)
	Move constructor. More...

	~EvdevInput ()
	Destructor. More...

const input_absinfo *	absInfo (unsigned int absEc) const
	Provides information about a specified absolute axis. More...

boost::signals2::connection	connect (const InputHandlersSptr &ihs)
	Connect the given InputHandlers to the end of the input event signal. More...

boost::signals2::connection	connect (const InputSignal::slot_type &slot, boost::signals2::connect_position at=boost::signals2::at_back)
	Make a connection to the input event signal. More...

boost::signals2::connection	connect (const InputSignal::group_type &group, const InputSignal::slot_type &slot, boost::signals2::connect_position at=boost::signals2::at_back)
	Make a connection to the input event signal. More...

boost::signals2::connection	connectExtended (const InputSignal::extended_slot_type &slot, boost::signals2::connect_position at=boost::signals2::at_back)
	Make a connection to the input event signal. More...

boost::signals2::connection	connectExtended (const InputSignal::group_type &group, const InputSignal::extended_slot_type &slot, boost::signals2::connect_position at=boost::signals2::at_back)
	Make a connection to the input event signal. More...

void	disconnect (const InputSignal::group_type &group)
	Disconnect a group from the input event signal. More...

template<typename Slot >
void	disconnect (const Slot &slotFunc)
	Disconnect a slot from the input event signal. More...

void	disconnectAll ()
	Disconnects all slots from the input event signal. More...

bool	eventsAvailable () const
	Returns true if there are events awaiting processing on this device. More...

bool	grab ()
	Attempts to gain exclusive access to the input device. More...

bool	hasEvent (EventTypeCode etc) const
	Returns true if the input device can produce events of the given type and code. More...

bool	hasEventCode (unsigned int et, unsigned int ec) const
	Returns true if the input device can produce events of the given type and code. More...

bool	hasEventType (unsigned int et) const
	Returns true if the input device can produce events of the given type. More...

bool	hasMultitouchSlots () const
	True if the input device has at least one multitouch slot. More...

InputHandlersSptr	makeConnectedHandlers ()
	Makes a new InputHandlers object, connects it to the input event signal for this device, and retruns the object. More...

std::string	name () const
	Reports the name of the device using libevdev_get_name(). More...

int	numMultitouchSlots () const
	Returns the number of slots supported by a multitouch input device. More...

void	open (const std::string &path)
	Opens the given input device file. More...

EvdevInput &	operator= (EvdevInput &&old) noexcept
	Move assignment. More...

void	respond (Poller *, int)
	Same as calling respondToNextEvent(); used with Poller. More...

void	respondToNextEvent ()
	Responds to the next input event on the device. More...

void	usePoller (Poller &p)
	Registers this object with the given Poller so that Poller::wait() will invoke respondToNextEvent(). More...

int	value (EventTypeCode etc) const
	Returns the current input value for the given event. More...

int	value (unsigned int et, unsigned int ec) const
	Returns the current input value for the given event. More...

Static Public Member Functions
static std::shared_ptr< EvdevInput >	make (const std::string &path)
	Creates a EvdevInput object managed by a std::shared_ptr. More...

Private Attributes
InputSignal	defReceiver
	Handles all input events. More...

libevdev *	dev = nullptr
	The object provided by libevdev that is needed to work with the input device. More...

int	fd
	The file descriptor to the input device file. More...

Detailed Description

Handles getting input from a specific input device using libevdev.

A single InputSignal processes all input events from the device. If InputSignals for specific events are needed, use InputHandlers. These objects can be connected with custom code, or with connect(const InputHandlersSptr &). An InputHandlers object may be used with multiple EvdevInput objects.

This class is not thread-safe, but this should not be an issue.

If used with Poller, this object must be managed by a std::shared_ptr.

Author: Jeff Jackowski

Examples:: evdevin.cpp.

Definition at line 29 of file EvdevInput.hpp.

Constructor & Destructor Documentation

◆ EvdevInput() [1/3]

duds::os::linux::EvdevInput::EvdevInput ( )

Constructs an EvdevInput object without opening a device file.

Before input events can be handled, open() must be called.

Definition at line 22 of file EvdevInput.cpp.

◆ EvdevInput() [2/3]

duds::os::linux::EvdevInput::EvdevInput ( const std::string & path )

Creates a EvdevInput object that will read input from the given device file.

Parameters

path	The device file. This is normally some variation of "/dev/input/event[0-9]+". Read-only access will be requested.

Exceptions

EvdevFileOpenError	The device file could not be opened.
EvdevInitError	The attempt to initialize libevdev failed. An error code will be added to the exception in a boost::errinfo_errno attribute.

Definition at line 24 of file EvdevInput.cpp.

◆ EvdevInput() [3/3]

duds::os::linux::EvdevInput::EvdevInput ( EvdevInput && old )

Move constructor.

Postcondition: The InputSignal, used to handle input events, within old will no longer be usable until after it is move-assigned.

Definition at line 50 of file EvdevInput.cpp.

◆ ~EvdevInput()

duds::os::linux::EvdevInput::~EvdevInput ( )

Destructor.

Definition at line 58 of file EvdevInput.cpp.

Referenced by make().

Member Function Documentation

◆ absInfo()

const input_absinfo * duds::os::linux::EvdevInput::absInfo ( unsigned int absEc ) const

Provides information about a specified absolute axis.

Parameters

absEc The event code for the axis to query. It must be for an event of type EV_ABS.

Returns: A non-null pointer to the data.

Exceptions

EvdevUnsupportedEvent The requested event lacks the information; either isn't an axis, or the axis is not provided by the input device.

Definition at line 137 of file EvdevInput.cpp.

Referenced by value().

◆ connect() [1/3]

boost::signals2::connection duds::os::linux::EvdevInput::connect ( const InputHandlersSptr & ihs )

Connect the given InputHandlers to the end of the input event signal.

Postcondition: When the last reference to the InputHandlers object is lost, it will be automaticlly removed from the event signal.

Parameters

ihs	The InputHandlers object that should process events from this input device.

Definition at line 147 of file EvdevInput.cpp.

Referenced by makeConnectedHandlers(), and value().

◆ connect() [2/3]

boost::signals2::connection duds::os::linux::EvdevInput::connect	(	const InputSignal::slot_type &	slot,
		boost::signals2::connect_position	at = `boost::signals2::at_back`
	)

inline

Make a connection to the input event signal.

See the Boost reference documentation for more details, or the tutorial for an overview of the whole boost::singals2 system.

Definition at line 230 of file EvdevInput.hpp.

◆ connect() [3/3]

boost::signals2::connection duds::os::linux::EvdevInput::connect	(	const InputSignal::group_type &	group,
		const InputSignal::slot_type &	slot,
		boost::signals2::connect_position	at = `boost::signals2::at_back`
	)

inline

Make a connection to the input event signal.

See the Boost reference documentation for more details, or the tutorial for an overview of the whole boost::singals2 system.

Definition at line 242 of file EvdevInput.hpp.

◆ connectExtended() [1/2]

boost::signals2::connection duds::os::linux::EvdevInput::connectExtended	(	const InputSignal::extended_slot_type &	slot,
		boost::signals2::connect_position	at = `boost::signals2::at_back`
	)

inline

Make a connection to the input event signal.

See the Boost reference documentation for more details, or the tutorial for an overview of the whole boost::singals2 system.

Definition at line 255 of file EvdevInput.hpp.

◆ connectExtended() [2/2]

boost::signals2::connection duds::os::linux::EvdevInput::connectExtended	(	const InputSignal::group_type &	group,
		const InputSignal::extended_slot_type &	slot,
		boost::signals2::connect_position	at = `boost::signals2::at_back`
	)

inline

Make a connection to the input event signal.

See the Boost reference documentation for more details, or the tutorial for an overview of the whole boost::singals2 system.

Definition at line 267 of file EvdevInput.hpp.

◆ disconnect() [1/2]

void duds::os::linux::EvdevInput::disconnect ( const InputSignal::group_type & group )

inline

Disconnect a group from the input event signal.

See the Boost reference documentation for more details, or the tutorial for an overview of the whole boost::singals2 system.

Definition at line 280 of file EvdevInput.hpp.

◆ disconnect() [2/2]

template<typename Slot >

void duds::os::linux::EvdevInput::disconnect ( const Slot & slotFunc )

inline

Disconnect a slot from the input event signal.

See the Boost reference documentation for more details, or the tutorial for an overview of the whole boost::singals2 system.

Definition at line 292 of file EvdevInput.hpp.

◆ disconnectAll()

void duds::os::linux::EvdevInput::disconnectAll ( )

inline

Disconnects all slots from the input event signal.

Definition at line 298 of file EvdevInput.hpp.

◆ eventsAvailable()

bool duds::os::linux::EvdevInput::eventsAvailable ( ) const

Returns true if there are events awaiting processing on this device.

When true, respondToNextEvent() will not block.

Examples:: evdevin.cpp.

Definition at line 106 of file EvdevInput.cpp.

Referenced by value().

◆ grab()

bool duds::os::linux::EvdevInput::grab ( )

Attempts to gain exclusive access to the input device.

Returns: True if exclusive access was granted.

Definition at line 80 of file EvdevInput.cpp.

Referenced by make().

◆ hasEvent()

bool duds::os::linux::EvdevInput::hasEvent ( EventTypeCode etc ) const

Returns true if the input device can produce events of the given type and code.

Parameters

etc	The event type and code to check.

Examples:: evdevin.cpp.

Definition at line 88 of file EvdevInput.cpp.

Referenced by hasEventCode(), and make().

◆ hasEventCode()

bool duds::os::linux::EvdevInput::hasEventCode	(	unsigned int	et,
		unsigned int	ec
	)		const

inline

Returns true if the input device can produce events of the given type and code.

Parameters

et	The event type to check.
ec	The event code to check.

Definition at line 134 of file EvdevInput.hpp.

◆ hasEventType()

bool duds::os::linux::EvdevInput::hasEventType ( unsigned int et ) const

Returns true if the input device can produce events of the given type.

Parameters

et	The event type to check.

Definition at line 84 of file EvdevInput.cpp.

Referenced by make().

◆ hasMultitouchSlots()

bool duds::os::linux::EvdevInput::hasMultitouchSlots ( ) const

inline

True if the input device has at least one multitouch slot.

Definition at line 148 of file EvdevInput.hpp.

◆ make()

static std::shared_ptr<EvdevInput> duds::os::linux::EvdevInput::make ( const std::string & path )

inlinestatic

Creates a EvdevInput object managed by a std::shared_ptr.

Parameters

path	The device file. This is normally some variation of "/dev/input/event[0-9]+". Read-only access will be requested.

Exceptions

EvdevFileOpenError	The device file could not be opened.
EvdevInitError	The attempt to initialize libevdev failed. An error code will be added to the exception in a boost::errinfo_errno attribute.

Definition at line 81 of file EvdevInput.hpp.

◆ makeConnectedHandlers()

InputHandlersSptr duds::os::linux::EvdevInput::makeConnectedHandlers ( )

Makes a new InputHandlers object, connects it to the input event signal for this device, and retruns the object.

Postcondition: When the last reference to the InputHandlers object is lost, it will be automaticlly removed from the event signal.

Examples:: evdevin.cpp.

Definition at line 156 of file EvdevInput.cpp.

Referenced by value().

◆ name()

std::string duds::os::linux::EvdevInput::name ( ) const

Reports the name of the device using libevdev_get_name().

Definition at line 76 of file EvdevInput.cpp.

Referenced by make().

◆ numMultitouchSlots()

int duds::os::linux::EvdevInput::numMultitouchSlots ( ) const

Returns the number of slots supported by a multitouch input device.

Some such devices support 0 slots. If a device has no slot support, the value will be -1.

Note: To check for no slots without checking for the difference between 0 slots and slots not supported, check for less than 1.

Definition at line 92 of file EvdevInput.cpp.

Referenced by hasEventCode(), and hasMultitouchSlots().

◆ open()

void duds::os::linux::EvdevInput::open ( const std::string & path )

Opens the given input device file.

Precondition: An input device file has not yet been opened by this object.

Parameters

path	The device file. This is normally some variation of "/dev/input/event[0-9]+". Read-only access will be requested.

Exceptions

EvdevFileOpenError	The device file could not be opened.
EvdevFileAlreadyOpenError	A device file is already open.
EvdevInitError	The attempt to initialize libevdev failed. An error code will be added to the exception in a boost::errinfo_errno attribute.

Examples:: evdevin.cpp.

Definition at line 28 of file EvdevInput.cpp.

Referenced by EvdevInput(), and make().

◆ operator=()

EvdevInput & duds::os::linux::EvdevInput::operator= ( EvdevInput && old )

noexcept

Move assignment.

Postcondition: The InputSignal, used to handle input events, within old will no longer be usable until after it is move-assigned.

Definition at line 67 of file EvdevInput.cpp.

Referenced by make().

◆ respond()

void duds::os::linux::EvdevInput::respond	(	Poller *	,
		int
	)

virtual

Same as calling respondToNextEvent(); used with Poller.

Implements duds::os::linux::PollResponder.

Definition at line 129 of file EvdevInput.cpp.

Referenced by value().

◆ respondToNextEvent()

void duds::os::linux::EvdevInput::respondToNextEvent ( )

Responds to the next input event on the device.

If there is currently no queued event, this function will block until an event is available. If there are one or more queued events, all queued events will be handled without blocking for more events.

The event processing is in a loop. The next event is read and then provided to the appropriate InputSignal for handling. The InputSignal is invoked directly; it runs on this thread, and no other events are read until the signal has completed. The loop will continue while no error has occured, and there are queued events. The queued event check will include events that have been queued during the time this function is running.

Examples:: evdevin.cpp.

Definition at line 110 of file EvdevInput.cpp.

Referenced by respond(), and value().

◆ usePoller()

void duds::os::linux::EvdevInput::usePoller ( Poller & p )

Registers this object with the given Poller so that Poller::wait() will invoke respondToNextEvent().

Precondition: This object is managed by a std::shared_ptr.

Parameters

p	The Poller object.

Definition at line 133 of file EvdevInput.cpp.

Referenced by value().

◆ value() [1/2]

int duds::os::linux::EvdevInput::value ( EventTypeCode etc ) const

Returns the current input value for the given event.

Parameters

etc	The event type and code to check.

Exceptions

EvdevUnsupportedEvent The event is not supplied by the input device.

Definition at line 96 of file EvdevInput.cpp.

Referenced by hasMultitouchSlots(), and value().

◆ value() [2/2]

int duds::os::linux::EvdevInput::value	(	unsigned int	et,
		unsigned int	ec
	)		const

inline

Returns the current input value for the given event.

Parameters

et	The event type to check.
ec	The event code to check.

Exceptions

EvdevUnsupportedEvent The event is not supplied by the input device.

Definition at line 165 of file EvdevInput.hpp.

Member Data Documentation

◆ defReceiver

InputSignal duds::os::linux::EvdevInput::defReceiver

private

Handles all input events.

Definition at line 37 of file EvdevInput.hpp.

Referenced by connect(), operator=(), and respondToNextEvent().

◆ dev

libevdev* duds::os::linux::EvdevInput::dev = nullptr

private

The object provided by libevdev that is needed to work with the input device.

Definition at line 42 of file EvdevInput.hpp.

Referenced by absInfo(), eventsAvailable(), grab(), hasEvent(), hasEventType(), name(), numMultitouchSlots(), open(), operator=(), respondToNextEvent(), value(), and ~EvdevInput().

◆ fd

int duds::os::linux::EvdevInput::fd

private

The file descriptor to the input device file.

Definition at line 46 of file EvdevInput.hpp.

Referenced by open(), operator=(), usePoller(), and ~EvdevInput().

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

Public Member Functions

Static Public Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ EvdevInput() [1/3]

◆ EvdevInput() [2/3]

◆ EvdevInput() [3/3]

◆ ~EvdevInput()

Member Function Documentation

◆ absInfo()

◆ connect() [1/3]

◆ connect() [2/3]

◆ connect() [3/3]

◆ connectExtended() [1/2]

◆ connectExtended() [2/2]

◆ disconnect() [1/2]

◆ disconnect() [2/2]

◆ disconnectAll()

◆ eventsAvailable()

◆ grab()

◆ hasEvent()

◆ hasEventCode()

◆ hasEventType()

◆ hasMultitouchSlots()

◆ make()

◆ makeConnectedHandlers()

◆ name()

◆ numMultitouchSlots()

◆ open()

◆ operator=()

◆ respond()

◆ respondToNextEvent()

◆ usePoller()

◆ value() [1/2]

◆ value() [2/2]

Member Data Documentation

◆ defReceiver

◆ dev

◆ fd