QCA::Console Class Reference

#include <QtCrypto>

Inheritance diagram for QCA::Console:

Public Types
enum	ChannelMode { Read , ReadWrite }
enum	TerminalMode { Default , Interactive }
enum	Type { Tty , Stdio }

Public Member Functions
	Console (Type type, ChannelMode cmode, TerminalMode tmode, QObject *parent=nullptr)
QByteArray	bytesLeftToRead ()
QByteArray	bytesLeftToWrite ()
ChannelMode	channelMode () const
void	release ()
TerminalMode	terminalMode () const
Type	type () const
Public Member Functions inherited from QObject
	QObject (QObject *parent)
QBindable< QString >	bindableObjectName ()
bool	blockSignals (bool block)
const QObjectList &	children () const const
QMetaObject::Connection	connect (const QObject *sender, const char *signal, const char *method, Qt::ConnectionType type) const const
void	deleteLater ()
void	destroyed (QObject *obj)
bool	disconnect (const char *signal, const QObject *receiver, const char *method) const const
bool	disconnect (const QObject *receiver, const char *method) const const
void	dumpObjectInfo () const const
void	dumpObjectTree () const const
QList< QByteArray >	dynamicPropertyNames () const const
virtual bool	event (QEvent *e)
virtual bool	eventFilter (QObject *watched, QEvent *event)
T	findChild (const QString &name, Qt::FindChildOptions options) const const
QList< T >	findChildren (const QRegularExpression &re, Qt::FindChildOptions options) const const
QList< T >	findChildren (const QString &name, Qt::FindChildOptions options) const const
QList< T >	findChildren (Qt::FindChildOptions options) const const
bool	inherits (const char *className) const const
void	installEventFilter (QObject *filterObj)
bool	isQuickItemType () const const
bool	isWidgetType () const const
bool	isWindowType () const const
void	killTimer (int id)
virtual const QMetaObject *	metaObject () const const
void	moveToThread (QThread *targetThread)
QString	objectName () const const
void	objectNameChanged (const QString &objectName)
QObject *	parent () const const
QVariant	property (const char *name) const const
	Q_CLASSINFO (Name, Value)
	Q_EMIT Q_EMIT
	Q_ENUM (...)
	Q_ENUM_NS (...)
	Q_ENUMS (...)
	Q_FLAG (...)
	Q_FLAG_NS (...)
	Q_FLAGS (...)
	Q_GADGET Q_GADGET
	Q_GADGET_EXPORT (EXPORT_MACRO)
	Q_INTERFACES (...)
	Q_INVOKABLE Q_INVOKABLE
	Q_MOC_INCLUDE Q_MOC_INCLUDE
	Q_NAMESPACE Q_NAMESPACE
	Q_NAMESPACE_EXPORT (EXPORT_MACRO)
	Q_OBJECT Q_OBJECT
	Q_PROPERTY (...)
	Q_REVISION Q_REVISION
	Q_SET_OBJECT_NAME (Object)
	Q_SIGNAL Q_SIGNAL
	Q_SIGNALS Q_SIGNALS
	Q_SLOT Q_SLOT
	Q_SLOTS Q_SLOTS
T	qobject_cast (const QObject *object)
T	qobject_cast (QObject *object)
	QT_NO_NARROWING_CONVERSIONS_IN_CONNECT QT_NO_NARROWING_CONVERSIONS_IN_CONNECT
void	removeEventFilter (QObject *obj)
void	setObjectName (const QString &name)
void	setObjectName (QAnyStringView name)
void	setParent (QObject *parent)
bool	setProperty (const char *name, const QVariant &value)
bool	setProperty (const char *name, QVariant &&value)
bool	signalsBlocked () const const
int	startTimer (int interval, Qt::TimerType timerType)
int	startTimer (std::chrono::milliseconds interval, Qt::TimerType timerType)
QThread *	thread () const const

Static Public Member Functions
static bool	isStdinRedirected ()
static bool	isStdoutRedirected ()
static Console *	stdioInstance ()
static Console *	ttyInstance ()
Static Public Member Functions inherited from QObject
QMetaObject::Connection	connect (const QObject *sender, const char *signal, const QObject *receiver, const char *method, Qt::ConnectionType type)
QMetaObject::Connection	connect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method, Qt::ConnectionType type)
QMetaObject::Connection	connect (const QObject *sender, PointerToMemberFunction signal, const QObject *context, Functor functor, Qt::ConnectionType type)
QMetaObject::Connection	connect (const QObject *sender, PointerToMemberFunction signal, const QObject *receiver, PointerToMemberFunction method, Qt::ConnectionType type)
QMetaObject::Connection	connect (const QObject *sender, PointerToMemberFunction signal, Functor functor)
bool	disconnect (const QMetaObject::Connection &connection)
bool	disconnect (const QObject *sender, const char *signal, const QObject *receiver, const char *method)
bool	disconnect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method)
bool	disconnect (const QObject *sender, PointerToMemberFunction signal, const QObject *receiver, PointerToMemberFunction method)
QString	tr (const char *sourceText, const char *disambiguation, int n)

Additional Inherited Members
Properties inherited from QObject
	objectName
Public Attributes inherited from QObject
typedef	QObjectList
Protected Member Functions inherited from QObject
virtual void	childEvent (QChildEvent *event)
virtual void	connectNotify (const QMetaMethod &signal)
virtual void	customEvent (QEvent *event)
virtual void	disconnectNotify (const QMetaMethod &signal)
bool	isSignalConnected (const QMetaMethod &signal) const const
int	receivers (const char *signal) const const
QObject *	sender () const const
int	senderSignalIndex () const const
virtual void	timerEvent (QTimerEvent *event)

Detailed Description

QCA Console system

QCA provides an API for asynchronous, event-based access to the console and stdin/stdout, as these facilities are otherwise not portable. The primary use of this system within QCA is for passphrase prompting in command-line applications, using the tty console type.

How it works: Create a Console object for the type of console desired, and then use ConsoleReference to act on the console. Only one ConsoleReference may operate on a Console at a time.

A Console object takes over either the physical console (Console::Tty type) or stdin/stdout (Console::Stdio type). Only one of each type may be created at a time.

Whenever code is written that needs a tty or stdio object, the code should first call one of the static methods (ttyInstance() or stdioInstance()) to see if a console object for the desired type exists already. If the object exists, use it. If it does not exist, the rule is that the relevant code should create the object, use the object, and then destroy the object when the operation is completed.

By following the above rule, you can write code that utilizes a console without the application having to create some master console object for you. Of course, if the application has created a console then it will be used.

The reason why there is a master console object is that it is not guaranteed that all I/O will survive creation and destruction of a console object. If you are using the Stdio Type, then you probably want a long-lived console object. It is possible to capture unprocessed I/O by calling bytesLeftToRead or bytesLeftToWrite. However, it is not expected that general console-needing code will call these functions when utilizing a temporary console. Thus, an application developer would need to create his own console object, invoke the console-needing code, and then do his own extraction of the unprocessed I/O if necessary. Another reason to extract unprocessed I/O is if you need to switch from Console back to standard functions (e.g. fgets() ).

Definition at line 560 of file qca_support.h.

Member Enumeration Documentation

ChannelMode

enum QCA::Console::ChannelMode

The type of I/O to use with the console object.

Enumerator
Read	Read only (equivalent to stdin)
ReadWrite	Read/write (equivalent to stdin and stdout)

Definition at line 575 of file qca_support.h.

TerminalMode

enum QCA::Console::TerminalMode

The nature of the console operation.

Enumerator
Default	use default terminal settings
Interactive	char-by-char input, no echo

Definition at line 584 of file qca_support.h.

Type

enum QCA::Console::Type

The type of console object.

Enumerator
Tty	physical console
Stdio	stdin/stdout

Definition at line 567 of file qca_support.h.

Constructor & Destructor Documentation

Console()

QCA::Console::Console	(	Type	type,
		ChannelMode	cmode,
		TerminalMode	tmode,
		QObject *	parent = nullptr )

Standard constructor.

Note that library code should not create a new Console object without checking whether there is already a Console object of the required Type. See the main documentation for Console for the rationale for this.

Parameters

type	the Type of Console object to create
cmode	the ChannelMode (I/O type) to use
tmode	the TerminalMode to use
parent	the parent object for this object

See also

ttyInstance() and stdioInstance for static methods that allow you to test whether there is already a Console object of the required Type, and if there is, obtain a reference to that object.

Member Function Documentation

bytesLeftToRead()

QByteArray QCA::Console::bytesLeftToRead

(

)

Obtain remaining data from the Console, awaiting a read operation.

bytesLeftToWrite()

QByteArray QCA::Console::bytesLeftToWrite

(

)

Obtain remaining data from the Console, awaiting a write operation.

channelMode()

ChannelMode QCA::Console::channelMode

(

)

const

The ChannelMode of this Console object.

isStdinRedirected()

static bool QCA::Console::isStdinRedirected ( )

static

Test whether standard input is redirected.

See also

type() and channelMode()

isStdoutRedirected()

static bool QCA::Console::isStdoutRedirected ( )

static

Test whether standard output is redirected.

See also

type() and channelMode()

release()

void QCA::Console::release

(

)

Release the Console.

This allows access to buffers containing any remaining data

stdioInstance()

static Console * QCA::Console::stdioInstance ( )

static

The current stdio-type console object.

Returns

null if there is no current Console of this type, otherwise the Console to use

terminalMode()

TerminalMode QCA::Console::terminalMode

(

)

const

The TerminalMode of this Console object.

ttyInstance()

static Console * QCA::Console::ttyInstance ( )

static

The current terminal-type console object.

Returns

null if there is no current Console of this type, otherwise the Console to use

type()

Type QCA::Console::type

(

)

const

The Type of this Console object.

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

• qca_support.h