LSeat Class Reference

Group of input and output devices. More...

Inheritance diagram for LSeat:

Public Member Functions
	LSeat (const void *params)
	Constructor of the LSeat class. More...
	~LSeat ()
	Destructor of the LSeat class. More...
const std::vector< LOutput * > &	outputs () const noexcept
	Vector of available outputs. More...
const std::vector< LInputDevice * > &	inputDevices () const noexcept
	Vector of available input devices. More...
const char *	name () const noexcept
	The seat name. More...
LToplevelRole *	activeToplevel () const noexcept
	Active toplevel surface. More...
const std::vector< LToplevelResizeSession * > &	toplevelResizeSessions () const noexcept
	Active LToplevelRole resize sessions. More...
const std::vector< LToplevelMoveSession * > &	toplevelMoveSessions () const noexcept
	Active LToplevelRole move sessions. More...
LPointer *	pointer () const noexcept
	Access to pointer events. More...
LKeyboard *	keyboard () const noexcept
	Access to keyboard events. More...
LTouch *	touch () const noexcept
	Access to touch events. More...
LDND *	dnd () const noexcept
	Access to the drag & drop session manager. More...
LClipboard *	clipboard () const noexcept
	Access to the clipboard manager. More...
void	dismissPopups () noexcept
	Close all popups. More...
LPopupRole *	topmostPopup () const noexcept
	Retrieve the topmost popup role. More...
Public Member Functions inherited from LFactoryObject
Type	factoryObjectType () const noexcept
	Gets the base factory object type. More...
Public Member Functions inherited from LObject
	LObject (const LObject &) noexcept
	Copy constructor. More...
LObject &	operator= (const LObject &) noexcept
	Assignment operator (each object has its own individual LWeak reference count). More...
void	setUserData (UIntPtr data) const noexcept
	Store an unsigned integer value/pointer. More...
UIntPtr	userData () const noexcept
	Retrieves the stored unsigned integer value/pointer. More...

Session
void	setTTY (UInt32 tty) noexcept
	Switches session. More...
Int32	openDevice (const char *path, Int32 *fd) noexcept
	Open a device. More...
Int32	closeDevice (Int32 id) noexcept
	Closes a device. More...
libseat *	libseatHandle () const noexcept
	Libseat handle. More...
bool	enabled () const noexcept
	Check the session state. More...

Virtual Methods
virtual void	nativeInputEvent (void *event)
	Native input backend events. More...
virtual void	enabledChanged ()
	Notify a change in the enabled() property. More...
virtual void	outputPlugged (LOutput *output)
	New available output. More...
virtual void	outputUnplugged (LOutput *output)
	Disconnected output. More...
virtual void	inputDevicePlugged (LInputDevice *device)
	New available input device. More...
virtual void	inputDeviceUnplugged (LInputDevice *device)
	Disconnected input device. More...

Additional Inherited Members
Public Types inherited from LFactoryObject
enum class	Type : Int32
	Base factory object types. More...
Protected Member Functions inherited from LObject
	LObject () noexcept=default
	Constructor of the LObject class. More...
virtual	~LObject () noexcept
	Destructor of the LObject class. More...
void	notifyDestruction () noexcept
	Notifies the object destruction. More...

Detailed Description

Group of input and output devices.

The LSeat class represents a collection of input and output devices such as a mouse, keyboard, touch screen, and displays (outputs). These devices are used within a session. Typically, for security reasons, access to these devices is restricted to a single process per session, often a Wayland compositor or X11 server.

To enable the libinput and DRM backends to manage devices without requiring superuser privileges, the openDevice() method is used to obtain device file descriptors. This method internally employs libseat.

By setting the environment variable LOUVRE_ENABLE_LIBSEAT to 0, libseat can be disabled, causing the compositor to launch without multi-session support. Consequently, certain features such as switching to another TTY may become unavailable.

Note

Disabling libseat may be necessary in scenarios where the compositor needs to be started remotely via SSH.

Constructor & Destructor Documentation

LSeat()

LSeat

(

const void *

params

)

Constructor of the LSeat class.

Parameters

params

Internal parameters provided in LCompositor::createObjectRequest().

~LSeat()

~LSeat

(

)

Destructor of the LSeat class.

Invoked after LCompositor::onAnticipatedObjectDestruction().

Member Function Documentation

outputs()

const std::vector< LOutput * > & outputs ( ) const

noexcept

Vector of available outputs.

This method provides a vector of currently available outputs. The vector includes connected outputs that can be initialized as well as those that are already initialized.
To obtain only initialized outputs, refer to LCompositor::outputs().

inputDevices()

const std::vector< LInputDevice * > & inputDevices ( ) const

noexcept

Vector of available input devices.

See also

inputDevicePlugged() and inputDeviceUnplugged().

name()

const char * name ( ) const

noexcept

The seat name.

This method returns the name of the seat (E.g. "seat0").

activeToplevel()

LToplevelRole * activeToplevel ( ) const

noexcept

Active toplevel surface.

This method returns the current LToplevelRole being configured with the LToplevelRole::State::Activated flag.
Only one toplevel surface can be active at a time, Louvre automatically deactivates other toplevels when one is activated.

Returns

The currently active LToplevelRole instance or nullptr if no toplevel is active.

toplevelResizeSessions()

const std::vector< LToplevelResizeSession * > & toplevelResizeSessions ( ) const

noexcept

Active LToplevelRole resize sessions.

See also

LToplevelResizeSession and LToplevelRole::startResizeRequest()

toplevelMoveSessions()

const std::vector< LToplevelMoveSession * > & toplevelMoveSessions ( ) const

noexcept

Active LToplevelRole move sessions.

See also

LToplevelMoveSession and LToplevelRole::startMoveRequest()

pointer()

LPointer* pointer ( ) const

inlinenoexcept

Access to pointer events.

Access to the LPointer instance used to receive pointer events from the backend and redirect them to clients.

keyboard()

LKeyboard* keyboard ( ) const

inlinenoexcept

Access to keyboard events.

Access to the LKeyboard instance used to receive keyboard events from the backend and redirect them to clients.

touch()

LTouch* touch ( ) const

inlinenoexcept

Access to touch events.

Access to the LTouch instance used to receive touch events from the backend and redirect them to clients.

dnd()

LDND* dnd ( ) const

inlinenoexcept

Access to the drag & drop session manager.

clipboard()

LClipboard* clipboard ( ) const

inlinenoexcept

Access to the clipboard manager.

dismissPopups()

void dismissPopups ( )

noexcept

Close all popups.

This method closes all active LPopupRole surfaces in reverse order of creation.

See also

LPopupRole::dismiss()

topmostPopup()

LPopupRole * topmostPopup ( ) const

noexcept

Retrieve the topmost popup role.

This method returns a pointer to the topmost popup.

Returns

A pointer to the topmost LPopupRole or nullptr if there is no popup.

setTTY()

void setTTY ( UInt32  tty )

noexcept

Switches session.

This method allows you to switch to another session (TTY). Louvre also allows switching sessions using the shortcuts Ctrl + Alt + [F1, F2, ..., F10].

Parameters

tty	TTY number.

openDevice()

Int32 openDevice ( const char *  path, Int32 *  fd  )

noexcept

Open a device.

Opens a device returning its ID and storing its file descriptor in fd.
The DRM and Libinput backends use this method to open GPUs and input devices respectively.

Parameters

path	Location of the device (E.g. "/dev/dri/card0")
fd	Stores the file descriptor.

Returns

The ID of the device or -1 in case of an error.

closeDevice()

Int32 closeDevice ( Int32  id )

noexcept

Closes a device.

This method is used by the input and graphic backends to close devices.

Parameters

id	The id of the device returned by openDevice().

Returns

0 if the device is closed successfully and -1 in case of error.

libseatHandle()

libseat * libseatHandle ( ) const

noexcept

Libseat handle.

struct libseat handle.

Note

Returns nullptr if libseat is not being used.

enabled()

bool enabled ( ) const

noexcept

Check the session state.

The session is considered disabled if the user is engaged in another active session (TTY).

Returns

true if the seat is active, false otherwise.

nativeInputEvent()

virtual void nativeInputEvent ( void *  event )

virtual

Native input backend events.

Override this virtual method if you want to access all events generated by the input backend.

Parameters

event

Opaque handle to the native backend event. When using the Libinput backend it corresponds to a libinput_event struct

Default implementation

void LSeat::nativeInputEvent(void *event)
{
    L_UNUSED(event);
}

enabledChanged()

virtual void enabledChanged ( )

virtual

Notify a change in the enabled() property.

Override this virtual method if you want to be notified when the seat is enabled or disabled.
The seat is enabled when the user is in the session (TTY) in which the compositor is running, and disabled when switching to a different session.

See also

setTTY()

Default implementation

void LSeat::enabledChanged()
{
    if (!enabled())
        return;
 
    cursor()->setVisible(false);
    cursor()->setVisible(true);
    cursor()->move(1, 1);
    compositor()->repaintAllOutputs();
}

outputPlugged()

virtual void outputPlugged ( LOutput *  output )

virtual

New available output.

This event is invoked by the graphic backend when a new output is available, for example when connecting an external monitor through an HDMI port.
The default implementation initializes the new output and positions it at the end (right) of the already initialized outputs.

Default Implementation

void LSeat::outputPlugged(LOutput *output)
{
    output->setScale(output->dpi() >= 200 ? 2 : 1);
 
    if (compositor()->outputs().empty())
        output->setPos(0);
    else
        output->setPos(compositor()->outputs().back()->pos() + LPoint(compositor()->outputs().back()->size().w(), 0));
 
    compositor()->addOutput(output);
    compositor()->repaintAllOutputs();
}

outputUnplugged()

virtual void outputUnplugged ( LOutput *  output )

virtual

Disconnected output.

This event is invoked by the graphic backend when an output is no longer available, for example when an external monitor connected to an HDMI port is disconnected.

The default implementation removes the output from the compositor and re-arranges the ones already initialized.

Note

Louvre automatically employs LCompositor::removeOutput() after this event, so calling it directly is not mandatory.

Default Implementation

void LSeat::outputUnplugged(LOutput *output)
{
    compositor()->removeOutput(output);
 
    Int32 totalWidth { 0 };
 
    for (LOutput *o : compositor()->outputs())
    {
        o->setPos(LPoint(totalWidth, 0));
        totalWidth += o->size().w();
    }
 
    compositor()->repaintAllOutputs();
}

inputDevicePlugged()

virtual void inputDevicePlugged ( LInputDevice *  device )

virtual

New available input device.

Default Implementation

void LSeat::inputDevicePlugged(LInputDevice *device)
{
    L_UNUSED(device);
}

inputDeviceUnplugged()

virtual void inputDeviceUnplugged ( LInputDevice *  device )

virtual

Disconnected input device.

Default Implementation

void LSeat::inputDeviceUnplugged(LInputDevice *device)
{
    L_UNUSED(device);
}