FreeRTOS::StaticStreamBuffer< N > Class Template Reference

Class that encapsulates the functionality of a FreeRTOS stream buffer. More...

#include <FreeRTOS/StreamBuffer.hpp>

Inheritance diagram for FreeRTOS::StaticStreamBuffer< N >:

Collaboration diagram for FreeRTOS::StaticStreamBuffer< N >:

Public Member Functions
	StaticStreamBuffer (const size_t triggerLevel=0)
	Construct a new StaticStreamBuffer object by calling StreamBufferHandle_t xStreamBufferCreateStatic( size_t xBufferSizeBytes, size_t xTriggerLevelBytes, uint8_t *pucStreamBufferStorageArea, StaticStreamBuffer_t *pxStaticStreamBuffer )
	StaticStreamBuffer (const StaticStreamBuffer &)=delete
StaticStreamBuffer &	operator= (const StaticStreamBuffer &)=delete
	StaticStreamBuffer (StaticStreamBuffer &&) noexcept=default
StaticStreamBuffer &	operator= (StaticStreamBuffer &&) noexcept=default
Public Member Functions inherited from FreeRTOS::StreamBufferBase
	StreamBufferBase (const StreamBufferBase &)=delete
StreamBufferBase &	operator= (const StreamBufferBase &)=delete
bool	isValid () const
	Function that checks if the underlying stream buffer handle is not NULL. This should be used to ensure a stream buffer has been created correctly.
size_t	send (const void *data, const size_t length, const TickType_t ticksToWait=portMAX_DELAY) const
	Function that calls size_t xStreamBufferSend( StreamBufferHandle_t xStreamBuffer, const void *pvTxData, size_t xDataLengthBytes, TickType_t xTicksToWait )
size_t	sendFromISR (bool &higherPriorityTaskWoken, const void *data, const size_t length) const
	Function that calls size_t xStreamBufferSendFromISR( StreamBufferHandle_t xStreamBuffer, const void *pvTxData, size_t xDataLengthBytes, BaseType_t *pxHigherPriorityTaskWoken )
size_t	sendFromISR (const void *data, const size_t length) const
	Function that calls size_t xStreamBufferSendFromISR( StreamBufferHandle_t xStreamBuffer, const void *pvTxData, size_t xDataLengthBytes, BaseType_t *pxHigherPriorityTaskWoken )
size_t	receive (void *buffer, const size_t bufferLength, const TickType_t ticksToWait=portMAX_DELAY) const
	Function that calls size_t xStreamBufferReceive( StreamBufferHandle_t xStreamBuffer, void *pvRxData, size_t xBufferLengthBytes, TickType_t xTicksToWait )
size_t	receiveFromISR (bool &higherPriorityTaskWoken, void *buffer, const size_t bufferLength) const
	Function that calls size_t xStreamBufferReceiveFromISR( StreamBufferHandle_t xStreamBuffer, void *pvRxData, size_t xBufferLengthBytes, BaseType_t *pxHigherPriorityTaskWoken )
size_t	receiveFromISR (void *buffer, const size_t bufferLength) const
	Function that calls size_t xStreamBufferReceiveFromISR( StreamBufferHandle_t xStreamBuffer, void *pvRxData, size_t xBufferLengthBytes, BaseType_t *pxHigherPriorityTaskWoken )
size_t	bytesAvailable () const
	Function that calls size_t xStreamBufferBytesAvailable( StreamBufferHandle_t xStreamBuffer )
size_t	spacesAvailable () const
	Function that calls size_t xStreamBufferSpacesAvailable( StreamBufferHandle_t xStreamBuffer )
bool	setTriggerLevel (const size_t triggerLevel=0) const
	Function that calls BaseType_t xStreamBufferSetTriggerLevel( StreamBufferHandle_t xStreamBuffer, size_t xTriggerLevel )
bool	reset () const
	Function that calls BaseType_t xStreamBufferReset( StreamBufferHandle_t xStreamBuffer )
bool	isEmpty () const
	Function that calls BaseType_t xStreamBufferIsEmpty( StreamBufferHandle_t xStreamBuffer )
bool	isFull () const
	Function that calls BaseType_t xStreamBufferIsFull( StreamBufferHandle_t xStreamBuffer )

Private Attributes
StaticStreamBuffer_t	staticStreamBuffer
uint8_t	storage [N]

Additional Inherited Members
Static Public Member Functions inherited from FreeRTOS::StreamBufferBase
static void *	operator new (size_t)=delete
static void *	operator new[] (size_t)=delete
static void *	operator new (size_t, void *ptr)
static void *	operator new[] (size_t, void *ptr)

Detailed Description

template<size_t N>
class FreeRTOS::StaticStreamBuffer< N >

Class that encapsulates the functionality of a FreeRTOS stream buffer.

If a stream buffer is created using this class then the RAM is provided by the application writer as part of the object instance and allows the RAM to be statically allocated at compile time.

Template Parameters

N	The size, in bytes, of the storage buffer for the stream buffer.

Constructor & Destructor Documentation

StaticStreamBuffer()

template<size_t N>

FreeRTOS::StaticStreamBuffer< N >::StaticStreamBuffer ( const size_t  triggerLevel = 0 )

inlineexplicit

Construct a new StaticStreamBuffer object by calling StreamBufferHandle_t xStreamBufferCreateStatic( size_t xBufferSizeBytes, size_t xTriggerLevelBytes, uint8_t *pucStreamBufferStorageArea, StaticStreamBuffer_t *pxStaticStreamBuffer )

StreamBuffer.hpp

See also

https://www.freertos.org/xStreamBufferCreateStatic.html

Parameters

triggerLevel

The number of bytes that must be in the stream buffer before a task that is blocked on the stream buffer to wait for data is moved out of the blocked state. For example, if a task is blocked on a read of an empty stream buffer that has a trigger level of 1 then the task will be unblocked when a single byte is written to the buffer or the task's block time expires. As another example, if a task is blocked on a read of an empty stream buffer that has a trigger level of 10 then the task will not be unblocked until the stream buffer contains at least 10 bytes or the task's block time expires. If a reading task's block time expires before the trigger level is reached then the task will still receive however many bytes are actually available. Setting a trigger level of 0 will result in a trigger level of 1 being used. It is not valid to specify a trigger level that is greater than the buffer size.

Example Usage

#include <FreeRTOS/StreamBuffer.hpp>
#include <FreeRTOS/Task.hpp>
 
class MyTask : public FreeRTOS::Task {
 public:
  void taskFunction() final;
};
 
void MyTask::taskFunction() {
  // Variable to hold the stream buffer and it's underlying storage.
  static FreeRTOS::StaticStreamBuffer<1000> streamBuffer;
 
  // Other code that uses the message buffer can go here.
}

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

• /home/runner/work/FreeRTOS-Cpp/FreeRTOS-Cpp/FreeRTOS-Cpp/include/FreeRTOS/StreamBuffer.hpp