Handles keystrokes. More...

#include <device/keyboard.h>

Inheritance diagram for Keyboard:

Collaboration diagram for Keyboard:

Public Member Functions
	Keyboard ()
	Constructor.

void	plugin ()
	Initialization of the keyboard.

bool	prologue () override
	Prologue of keyboard interrupts.

void	epilogue () override
	Epilogue of keyboard interrupts.

Public Member Functions inherited from Gate
	Gate ()
	Constructor.

virtual	~Gate ()
	Destructor.

bool	is_queued () const
	Status about the epilogue.

void	set_queued (bool val)
	Set epilogue status.

Private Member Functions
	Keyboard (const Keyboard &)=delete

Keyboard &	operator= (const Keyboard &)=delete

Private Attributes
BBuffer< Key, 16 >	prologue_keys
	Buffer for pressed keys in prologue.

Additional Inherited Members
Protected Member Functions inherited from Queue< T, ContainerType >::Node
	Node ()

Detailed Description

Handles keystrokes.

This class ensures correct initialization of the keyboard and, above all, its interrupt handling.

Constructor & Destructor Documentation

◆ Keyboard() [1/2]

Keyboard::Keyboard ( const Keyboard & )

privatedelete

◆ Keyboard() [2/2]

Keyboard::Keyboard ( )

inline

Constructor.

Member Function Documentation

◆ operator=()

Keyboard & Keyboard::operator= ( const Keyboard & )

privatedelete

◆ plugin()

void Keyboard::plugin ( )

Initialization of the keyboard.

Initialization of the keyboard and activation of the specific interrupt handling: The object will register itself at the Plugbox and configure the IOAPIC to receive the corresponding interrupts.

Note: The keyboard interrupts should be configured as level triggered. According to the standard we would have to check the corresponding entry in ACPI::MADS::Interrupt_Source_Override and use these values. Most likely this would suggest an edge-triggered mode – which would work as well. However, using a level-triggered mode is more forgiving because it resends the interrupt request even if an interrupt was lost (e.g. the required handling, retrieving the buffer entry, was not performed).

◆ prologue()

bool Keyboard::prologue ( )

overridevirtual

Prologue of keyboard interrupts.

This method directly handles interrupts caused by the keyboard. Since multiple interrupts are triggered on a keystroke (press & release) it produces not always a printable ASCII character – therefore only valid keys are handled in the Keyboard::epilogue.

Since the buffer is limited, it also ensures that a valid key is not overwritten by a subsequent prologue before it was handled in the Keyboard::epilogue.

Note: If a keystroke would exceed the buffer, the new key is dropped – previous keystrokes have a higher priority in the buffer.

Returns: true if a new Key was stored in the buffer and has to be processed in the Keyboard::epilogue.

Todo:: Implement Method. A buffer with a size of 1 (that is just a variable) is sufficient

Optional:: Increase the buffer size using BBuffer

Implements Gate.

◆ epilogue()

void Keyboard::epilogue ( )

overridevirtual

Epilogue of keyboard interrupts.

The character of the keystroke is read out and printed on the screen using the TextStream.

Todo:: Implement Method

Reimplemented from Gate.

Member Data Documentation

◆ prologue_keys

BBuffer<Key, 16> Keyboard::prologue_keys

private

Buffer for pressed keys in prologue.

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

device/keyboard.h
device/keyboard.cc

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members