Async source abstraction emitting data events in caller provided byte buffers. More...

#include <AsyncStreams.h>

Inheritance diagram for SC::AsyncReadableStream:

Classes
struct	Request

Public Member Functions
Result	init (AsyncBuffersPool &buffersPool)
	Emitted when the underlying resource has been closed.

Result	start ()
	Starts the readable stream, that will emit eventData.

void	pause ()
	Pauses the readable stream (that can be later resumed)

void	resumeReading ()
	Resumes the readable stream paused by AsyncReadableStream::pause.

void	destroy ()
	Forcefully destroys the readable stream before calling end event releasing all resources.

bool	isEnded () const
	Returns true if the stream is ended (AsyncReadableStream::end has been called)

AsyncBuffersPool &	getBuffersPool ()
	Obtains the AsyncBuffersPool to request more buffers.

constexpr void	setReadQueue (Span< Request > requests)
	Sets the read queue for this readable stream.

size_t	getReadQueueSize () const
	Returns the size of read queue.

bool	push (AsyncBufferView::ID bufferID, size_t newSize)
	Use push from inside AsyncReadableStream::asyncRead function to queue received data.

void	pushEnd ()
	Use pushEnd from inside AsyncReadableStream::asyncRead to signal production end.

void	reactivate (bool doReactivate)
	Use reactivate(true) from inside AsyncReadableStream::asyncRead function to ask the state machine to invoke asyncRead again.

void	emitError (Result error)
	Signals an async error received.

bool	getBufferOrPause (size_t minumumSizeInBytes, AsyncBufferView::ID &bufferID, Span< char > &data)
	Returns an unused buffer from pool or pauses the stream if none is available.

Public Attributes
Function< Result()>	asyncRead
	Function that every stream must define to implement its custom read operation.

Event< MaxListeners, Result >	eventError

Event< MaxListeners, AsyncBufferView::ID >	eventData
	Emitted when an error occurs.

Event< MaxListeners >	eventEnd
	Emitted when a new buffer has been read.

Event< MaxListeners >	eventClose
	Emitted when there is no more data.

Static Public Attributes
static constexpr int	MaxListeners = 8

Detailed Description

Async source abstraction emitting data events in caller provided byte buffers.

After AsyncReadableStream::start it will start emitting AsyncReadableStream::eventData with buffers. User must provide a custom async red implementation in AsyncReadableStream::asyncRead. The stream must be paused when the AsyncBuffersPool is full (use AsyncReadableStream::getBufferOrPause). Once the stream is ended, it will emit AsyncReadableStream::eventEnd and it cannot be used further. AsyncReadableStream::eventError will be emitted when an error occurs in any phase.

Member Function Documentation

◆ destroy()

void SC::AsyncReadableStream::destroy ( )

Forcefully destroys the readable stream before calling end event releasing all resources.

Note: It's safe to call destroy in any state and also when already destroyed (it's idempotent)

◆ emitError()

void SC::AsyncReadableStream::emitError ( Result error )

Signals an async error received.

◆ getBufferOrPause()

bool SC::AsyncReadableStream::getBufferOrPause	(	size_t	minumumSizeInBytes,
		AsyncBufferView::ID &	bufferID,
		Span< char > &	data )

nodiscard

Returns an unused buffer from pool or pauses the stream if none is available.

◆ getBuffersPool()

AsyncBuffersPool & SC::AsyncReadableStream::getBuffersPool ( )

Obtains the AsyncBuffersPool to request more buffers.

◆ getReadQueueSize()

size_t SC::AsyncReadableStream::getReadQueueSize ( ) const

inlinenodiscard

Returns the size of read queue.

◆ init()

Result SC::AsyncReadableStream::init ( AsyncBuffersPool & buffersPool )

Emitted when the underlying resource has been closed.

Inits the readable stream with an AsyncBuffersPool instance that will provide memory for it

Parameters

buffersPool An instance of AsyncBuffersPool providing read buffers

Note: Remember to call AsyncReadableStream::setReadQueue before calling init

◆ isEnded()

bool SC::AsyncReadableStream::isEnded ( ) const

inlinenodiscard

Returns true if the stream is ended (AsyncReadableStream::end has been called)

◆ pause()

void SC::AsyncReadableStream::pause ( )

Pauses the readable stream (that can be later resumed)

◆ push()

bool SC::AsyncReadableStream::push	(	AsyncBufferView::ID	bufferID,
		size_t	newSize )

nodiscard

Use push from inside AsyncReadableStream::asyncRead function to queue received data.

Returns: true if the caller can continue pushing

◆ pushEnd()

void SC::AsyncReadableStream::pushEnd ( )

Use pushEnd from inside AsyncReadableStream::asyncRead to signal production end.

◆ reactivate()

void SC::AsyncReadableStream::reactivate ( bool doReactivate )

Use reactivate(true) from inside AsyncReadableStream::asyncRead function to ask the state machine to invoke asyncRead again.

◆ resumeReading()

void SC::AsyncReadableStream::resumeReading ( )

Resumes the readable stream paused by AsyncReadableStream::pause.

◆ setReadQueue()

void SC::AsyncReadableStream::setReadQueue ( Span< Request > requests )

inlineconstexpr

Sets the read queue for this readable stream.

◆ start()

Result SC::AsyncReadableStream::start ( )

Starts the readable stream, that will emit eventData.

Member Data Documentation

◆ asyncRead

Function<Result()> SC::AsyncReadableStream::asyncRead

Function that every stream must define to implement its custom read operation.

◆ eventClose

Event<MaxListeners> SC::AsyncReadableStream::eventClose

Emitted when there is no more data.

◆ eventData

Event<MaxListeners, AsyncBufferView::ID> SC::AsyncReadableStream::eventData

Emitted when an error occurs.

◆ eventEnd

Event<MaxListeners> SC::AsyncReadableStream::eventEnd

Emitted when a new buffer has been read.

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

AsyncStreams.h

Classes

Public Member Functions

Public Attributes

Static Public Attributes