IODevice backed by an in-memory Buffer. More...

#include <bufferiodevice.h>

Inheritance diagram for BufferIODevice:

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Collaboration diagram for BufferIODevice:

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Public Member Functions
	BufferIODevice (Buffer buffer, ObjectBase parent=nullptr)
	Constructs a BufferIODevice with an external Buffer.

	BufferIODevice (ObjectBase *parent=nullptr)
	Constructs a BufferIODevice with no buffer.

	~BufferIODevice () override
	Destructor.

void	setBuffer (Buffer *buffer)
	Sets the underlying Buffer.

Buffer *	buffer () const
	Returns the underlying Buffer, or nullptr.

Error	open (OpenMode mode) override
	Opens the device with the specified mode.

Error	close () override
	Closes the device.

bool	isOpen () const override
	Returns true if the device is open.

int64_t	read (void *data, int64_t maxSize) override
	Reads up to maxSize bytes into data.

int64_t	write (const void *data, int64_t maxSize) override
	Writes up to maxSize bytes from data.

int64_t	bytesAvailable () const override
	Returns the number of bytes available for reading.

bool	isSequential () const override
	Returns true if the device is sequential (non-seekable).

Error	seek (int64_t pos) override
	Seeks to the given byte offset from the beginning.

int64_t	pos () const override
	Returns the current read/write position.

Result< int64_t >	size () const override
	Returns the total size of the device in bytes.

bool	atEnd () const override
	Returns true if the current position is at the end.

Public Member Functions inherited from IODevice
	IODevice (ObjectBase *parent=nullptr)
	Constructs an IODevice.

virtual	~IODevice ()
	Destructor.

virtual void	flush ()
	Flushes any buffered output data to the underlying device.

virtual bool	waitForReadyRead (unsigned int timeoutMs=0)
	Waits until data is available for reading or timeout.

virtual bool	waitForBytesWritten (unsigned int timeoutMs=0)
	Waits until all pending data has been written or timeout.

OpenMode	openMode () const
	Returns the current open mode.

bool	isReadable () const
	Returns true if the device is readable.

bool	isWritable () const
	Returns true if the device is writable.

Error	error () const
	Returns the current error state.

void	clearError ()
	Clears the error state to Ok.

	PROMEKI_SIGNAL (readyRead)
	Emitted when data is available for reading.

	PROMEKI_SIGNAL (bytesWritten, int64_t)
	Emitted when bytes have been written.

	PROMEKI_SIGNAL (errorOccurred, Error)
	Emitted when an error occurs.

	PROMEKI_SIGNAL (aboutToClose)
	Emitted just before the device is closed.

Public Member Functions inherited from ObjectBase
	ObjectBase (ObjectBase *p=nullptr)
	Default ObjectBase constructor.

virtual	~ObjectBase ()
	Destructor. Emits aboutToDestroy, detaches from parent, and destroys children.

ObjectBase *	parent () const
	Returns the parent object, if one. nullptr if none.

void	setParent (ObjectBase *p)
	Sets the parent of this object. If the object already has a parent, it will be removed as a child from the old parent and added as a child to the new one.

const ObjectBaseList &	childList () const
	Returns a list of children of this object.

template<typename... Args>
int	registerSlot (Slot< Args... > *slot)
	Registers a slot with this object and assigns it an ID.

EventLoop *	eventLoop () const
	Returns the EventLoop this object is affiliated with.

void	moveToThread (EventLoop *loop)
	Changes the EventLoop affinity of this object.

int	startTimer (unsigned int intervalMs, bool singleShot=false)
	Starts a timer on this object's EventLoop.

void	stopTimer (int timerId)
	Stops a timer previously started with startTimer().

template<typename... Args>
PROMEKI_NAMESPACE_BEGIN void	connect (Signal< Args... > signal, Slot< Args... > slot)

Additional Inherited Members
Public Types inherited from IODevice
enum	OpenMode { NotOpen = 0x00 , ReadOnly = 0x01 , WriteOnly = 0x02 , ReadWrite = ReadOnly \| WriteOnly , Append = 0x04 \| WriteOnly }
	Mode flags controlling how a device is opened. More...

Public Types inherited from ObjectBase
using	SlotVariantFunc = std::function< void(const VariantList &)>
	Function type for invoking a slot with a list of Variants.

Static Public Member Functions inherited from ObjectBase
static const MetaInfo &	metaInfo ()
	Returns the MetaInfo for the ObjectBase class.

template<typename... Args>
static void	connect (Signal< Args... > signal, Slot< Args... > slot)
	connects a signal and slot together. This function assumes both the signal and slot exist in a ObjectBase or derived object

Public Attributes inherited from ObjectBase
Signal< ObjectBase * >	aboutToDestroySignal = Signal< ObjectBase * >(this, aboutToDestroySignalName)

Static Public Attributes inherited from ObjectBase
static constexpr const char *	aboutToDestroySignalName = PROMEKI_STRINGIFY( aboutToDestroy ) "(" PROMEKI_STRINGIFY_ARGS( ObjectBase * ) ")"

static SignalMeta	aboutToDestroySignalMeta = SignalMeta(metaInfo(), aboutToDestroySignalName)

Protected Member Functions inherited from IODevice
void	setOpenMode (OpenMode mode)
	Sets the open mode.

void	setError (const Error &err)
	Sets the error state and emits errorOccurred.

Protected Member Functions inherited from ObjectBase
ObjectBase *	signalSender ()
	Returns the ObjectBase that emitted the signal currently being handled.

virtual void	event (Event *e)
	Called by EventLoop to deliver events to this object.

virtual void	timerEvent (TimerEvent *e)
	Called when a timer fires for this object.

Detailed Description

IODevice backed by an in-memory Buffer.

BufferIODevice provides seekable, random-access I/O over a promeki Buffer. It is useful wherever an IODevice interface is expected but the data lives in memory — for example, unit-testing code that operates on IODevice, or wiring a DataStream to a memory buffer.

Ownership: BufferIODevice does not own the Buffer; the caller must ensure the Buffer outlives the device. If no external Buffer is provided, the device uses an internal default-constructed Buffer (invalid/empty) and all operations will fail until a valid Buffer is set.

Write growth: When opened for writing, writes past the current logical size() succeed as long as space remains in availSize(). The device advances size() to track the high-water mark. Writes that would exceed availSize() return an error.

Constructor & Destructor Documentation

◆ BufferIODevice() [1/2]

BufferIODevice::BufferIODevice	(	Buffer *	buffer,
		ObjectBase *	parent = `nullptr`
	)

explicit

Constructs a BufferIODevice with an external Buffer.

Parameters

buffer	Pointer to the Buffer to use. Must remain valid for the lifetime of this device.
parent	The parent object, or nullptr.

◆ BufferIODevice() [2/2]

BufferIODevice::BufferIODevice ( ObjectBase * parent = nullptr )

explicit

Constructs a BufferIODevice with no buffer.

A buffer must be set via setBuffer() before the device can be opened.

Parameters

parent The parent object, or nullptr.

Member Function Documentation

◆ atEnd()

bool BufferIODevice::atEnd ( ) const

overridevirtual

Returns true if the current position is at the end.

The default implementation returns true if pos() >= size().

Returns: true if at end of device.

Reimplemented from IODevice.

◆ buffer()

Buffer * BufferIODevice::buffer ( ) const

inline

Returns the underlying Buffer, or nullptr.

Returns: The buffer pointer.

◆ bytesAvailable()

int64_t BufferIODevice::bytesAvailable ( ) const

overridevirtual

Returns the number of bytes available for reading.

The default implementation returns 0.

Returns: The number of bytes available.

Reimplemented from IODevice.

◆ close()

Error BufferIODevice::close ( )

overridevirtual

Closes the device.

Returns: Error::Ok on success, or an error on failure.

Implements IODevice.

◆ isOpen()

bool BufferIODevice::isOpen ( ) const

overridevirtual

Returns true if the device is open.

Returns: true if the device is currently open.

Implements IODevice.

◆ isSequential()

bool BufferIODevice::isSequential ( ) const

overridevirtual

Returns true if the device is sequential (non-seekable).

Sequential devices (pipes, sockets) cannot be seeked. The default implementation returns false.

Returns: true if the device is sequential.

Reimplemented from IODevice.

◆ open()

Error BufferIODevice::open ( OpenMode mode )

overridevirtual

Opens the device with the specified mode.

Parameters

mode	The open mode (ReadOnly, WriteOnly, ReadWrite, or Append).

Returns: Error::Ok on success, or an error on failure.

Implements IODevice.

◆ pos()

int64_t BufferIODevice::pos ( ) const

overridevirtual

Returns the current read/write position.

The default implementation returns 0.

Returns: The current position in bytes.

Reimplemented from IODevice.

◆ read()

int64_t BufferIODevice::read	(	void *	data,
		int64_t	maxSize
	)

overridevirtual

Reads up to maxSize bytes into data.

Parameters

data	Pointer to the buffer to read into.
maxSize	Maximum number of bytes to read.

Returns: The number of bytes read, or -1 on error.

Implements IODevice.

◆ seek()

Error BufferIODevice::seek ( int64_t pos )

overridevirtual

Seeks to the given byte offset from the beginning.

Parameters

pos	The byte offset to seek to.

Returns: Error::Ok on success, or an error on failure.

Reimplemented from IODevice.

◆ setBuffer()

void BufferIODevice::setBuffer ( Buffer * buffer )

Sets the underlying Buffer.

The device must not be open when calling this.

Parameters

buffer Pointer to the Buffer to use.

◆ size()

Result< int64_t > BufferIODevice::size ( ) const

overridevirtual

Returns the total size of the device in bytes.

The default implementation returns 0.

Returns: A Result containing the device size, or an error.

Reimplemented from IODevice.

◆ write()

int64_t BufferIODevice::write	(	const void *	data,
		int64_t	maxSize
	)

overridevirtual

Writes up to maxSize bytes from data.

Parameters

data	Pointer to the data to write.
maxSize	Number of bytes to write.

Returns: The number of bytes written, or -1 on error.

Implements IODevice.

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

include/promeki/core/bufferiodevice.h

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ BufferIODevice() [1/2]

◆ BufferIODevice() [2/2]

Member Function Documentation

◆ atEnd()

◆ buffer()

◆ bytesAvailable()

◆ close()

◆ isOpen()

◆ isSequential()

◆ open()

◆ pos()

◆ read()

◆ seek()

◆ setBuffer()

◆ size()

◆ write()