Fix race condition bugs when reading and writing to message buffers (#264)
* Fix inaccuracies in prvWriteBytesToBuffer description
* Perform atomic message write in prvWriteMessageToBuffer
* Remove unnecessary length arg from prvReadMessageFromBuffer
* Perform atomic message read in prvReadBytesFromBuffer
* Apply SpacesAvailable() fix
Original author: RichardBarry
* Apply review feedback
* Edit some prv functions for simplicity and consistency
- prvWriteMessageToBuffer
- prvReadMessageFromBuffer
- prvWriteBytesToBuffer
- prvReadBytesFromBuffer
* Significant simplification of prvWriteMessageToBuffer
* fixup off-by-one comment indentation
Co-authored-by: alfred gedeon <28123637+alfred2g@users.noreply.github.com>
Co-authored-by: RichardBarry <3073890+RichardBarry@users.noreply.github.com>
diff --git a/stream_buffer.c b/stream_buffer.c
index 0c4f429..382dd08 100644
--- a/stream_buffer.c
+++ b/stream_buffer.c
@@ -1,1314 +1,1305 @@
-/*
- * FreeRTOS Kernel V10.4.3
- * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy of
- * this software and associated documentation files (the "Software"), to deal in
- * the Software without restriction, including without limitation the rights to
- * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
- * the Software, and to permit persons to whom the Software is furnished to do so,
- * subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
- * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
- * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
- * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- *
- * https://www.FreeRTOS.org
- * https://github.com/FreeRTOS
- *
- */
-
-/* Standard includes. */
-#include <stdint.h>
-#include <string.h>
-
-/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
- * all the API functions to use the MPU wrappers. That should only be done when
- * task.h is included from an application file. */
-#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
-
-/* FreeRTOS includes. */
-#include "FreeRTOS.h"
-#include "task.h"
-#include "stream_buffer.h"
-
-#if ( configUSE_TASK_NOTIFICATIONS != 1 )
- #error configUSE_TASK_NOTIFICATIONS must be set to 1 to build stream_buffer.c
-#endif
-
-/* Lint e961, e9021 and e750 are suppressed as a MISRA exception justified
- * because the MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined
- * for the header files above, but not in this file, in order to generate the
- * correct privileged Vs unprivileged linkage and placement. */
-#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e961 !e750 !e9021. */
-
-/* If the user has not provided application specific Rx notification macros,
- * or #defined the notification macros away, then provide default implementations
- * that uses task notifications. */
-/*lint -save -e9026 Function like macros allowed and needed here so they can be overridden. */
-#ifndef sbRECEIVE_COMPLETED
- #define sbRECEIVE_COMPLETED( pxStreamBuffer ) \
- vTaskSuspendAll(); \
- { \
- if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL ) \
- { \
- ( void ) xTaskNotify( ( pxStreamBuffer )->xTaskWaitingToSend, \
- ( uint32_t ) 0, \
- eNoAction ); \
- ( pxStreamBuffer )->xTaskWaitingToSend = NULL; \
- } \
- } \
- ( void ) xTaskResumeAll();
-#endif /* sbRECEIVE_COMPLETED */
-
-#ifndef sbRECEIVE_COMPLETED_FROM_ISR
- #define sbRECEIVE_COMPLETED_FROM_ISR( pxStreamBuffer, \
- pxHigherPriorityTaskWoken ) \
- { \
- UBaseType_t uxSavedInterruptStatus; \
- \
- uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR(); \
- { \
- if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL ) \
- { \
- ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToSend, \
- ( uint32_t ) 0, \
- eNoAction, \
- pxHigherPriorityTaskWoken ); \
- ( pxStreamBuffer )->xTaskWaitingToSend = NULL; \
- } \
- } \
- portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus ); \
- }
-#endif /* sbRECEIVE_COMPLETED_FROM_ISR */
-
-/* If the user has not provided an application specific Tx notification macro,
- * or #defined the notification macro away, them provide a default implementation
- * that uses task notifications. */
-#ifndef sbSEND_COMPLETED
- #define sbSEND_COMPLETED( pxStreamBuffer ) \
- vTaskSuspendAll(); \
- { \
- if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL ) \
- { \
- ( void ) xTaskNotify( ( pxStreamBuffer )->xTaskWaitingToReceive, \
- ( uint32_t ) 0, \
- eNoAction ); \
- ( pxStreamBuffer )->xTaskWaitingToReceive = NULL; \
- } \
- } \
- ( void ) xTaskResumeAll();
-#endif /* sbSEND_COMPLETED */
-
-#ifndef sbSEND_COMPLETE_FROM_ISR
- #define sbSEND_COMPLETE_FROM_ISR( pxStreamBuffer, pxHigherPriorityTaskWoken ) \
- { \
- UBaseType_t uxSavedInterruptStatus; \
- \
- uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR(); \
- { \
- if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL ) \
- { \
- ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToReceive, \
- ( uint32_t ) 0, \
- eNoAction, \
- pxHigherPriorityTaskWoken ); \
- ( pxStreamBuffer )->xTaskWaitingToReceive = NULL; \
- } \
- } \
- portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus ); \
- }
-#endif /* sbSEND_COMPLETE_FROM_ISR */
-/*lint -restore (9026) */
-
-/* The number of bytes used to hold the length of a message in the buffer. */
-#define sbBYTES_TO_STORE_MESSAGE_LENGTH ( sizeof( configMESSAGE_BUFFER_LENGTH_TYPE ) )
-
-/* Bits stored in the ucFlags field of the stream buffer. */
-#define sbFLAGS_IS_MESSAGE_BUFFER ( ( uint8_t ) 1 ) /* Set if the stream buffer was created as a message buffer, in which case it holds discrete messages rather than a stream. */
-#define sbFLAGS_IS_STATICALLY_ALLOCATED ( ( uint8_t ) 2 ) /* Set if the stream buffer was created using statically allocated memory. */
-
-/*-----------------------------------------------------------*/
-
-/* Structure that hold state information on the buffer. */
-typedef struct StreamBufferDef_t /*lint !e9058 Style convention uses tag. */
-{
- volatile size_t xTail; /* Index to the next item to read within the buffer. */
- volatile size_t xHead; /* Index to the next item to write within the buffer. */
- size_t xLength; /* The length of the buffer pointed to by pucBuffer. */
- size_t xTriggerLevelBytes; /* The number of bytes that must be in the stream buffer before a task that is waiting for data is unblocked. */
- volatile TaskHandle_t xTaskWaitingToReceive; /* Holds the handle of a task waiting for data, or NULL if no tasks are waiting. */
- volatile TaskHandle_t xTaskWaitingToSend; /* Holds the handle of a task waiting to send data to a message buffer that is full. */
- uint8_t * pucBuffer; /* Points to the buffer itself - that is - the RAM that stores the data passed through the buffer. */
- uint8_t ucFlags;
-
- #if ( configUSE_TRACE_FACILITY == 1 )
- UBaseType_t uxStreamBufferNumber; /* Used for tracing purposes. */
- #endif
-} StreamBuffer_t;
-
-/*
- * The number of bytes available to be read from the buffer.
- */
-static size_t prvBytesInBuffer( const StreamBuffer_t * const pxStreamBuffer ) PRIVILEGED_FUNCTION;
-
-/*
- * Add xCount bytes from pucData into the pxStreamBuffer message buffer.
- * Returns the number of bytes written, which will either equal xCount in the
- * success case, or 0 if there was not enough space in the buffer (in which case
- * no data is written into the buffer).
- */
-static size_t prvWriteBytesToBuffer( StreamBuffer_t * const pxStreamBuffer,
- const uint8_t * pucData,
- size_t xCount ) PRIVILEGED_FUNCTION;
-
-/*
- * If the stream buffer is being used as a message buffer, then reads an entire
- * message out of the buffer. If the stream buffer is being used as a stream
- * buffer then read as many bytes as possible from the buffer.
- * prvReadBytesFromBuffer() is called to actually extract the bytes from the
- * buffer's data storage area.
- */
-static size_t prvReadMessageFromBuffer( StreamBuffer_t * pxStreamBuffer,
- void * pvRxData,
- size_t xBufferLengthBytes,
- size_t xBytesAvailable,
- size_t xBytesToStoreMessageLength ) PRIVILEGED_FUNCTION;
-
-/*
- * If the stream buffer is being used as a message buffer, then writes an entire
- * message to the buffer. If the stream buffer is being used as a stream
- * buffer then write as many bytes as possible to the buffer.
- * prvWriteBytestoBuffer() is called to actually send the bytes to the buffer's
- * data storage area.
- */
-static size_t prvWriteMessageToBuffer( StreamBuffer_t * const pxStreamBuffer,
- const void * pvTxData,
- size_t xDataLengthBytes,
- size_t xSpace,
- size_t xRequiredSpace ) PRIVILEGED_FUNCTION;
-
-/*
- * Read xMaxCount bytes from the pxStreamBuffer message buffer and write them
- * to pucData.
- */
-static size_t prvReadBytesFromBuffer( StreamBuffer_t * pxStreamBuffer,
- uint8_t * pucData,
- size_t xMaxCount,
- size_t xBytesAvailable ) PRIVILEGED_FUNCTION;
-
-/*
- * Called by both pxStreamBufferCreate() and pxStreamBufferCreateStatic() to
- * initialise the members of the newly created stream buffer structure.
- */
-static void prvInitialiseNewStreamBuffer( StreamBuffer_t * const pxStreamBuffer,
- uint8_t * const pucBuffer,
- size_t xBufferSizeBytes,
- size_t xTriggerLevelBytes,
- uint8_t ucFlags ) PRIVILEGED_FUNCTION;
-
-/*-----------------------------------------------------------*/
-
-#if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
-
- StreamBufferHandle_t xStreamBufferGenericCreate( size_t xBufferSizeBytes,
- size_t xTriggerLevelBytes,
- BaseType_t xIsMessageBuffer )
- {
- uint8_t * pucAllocatedMemory;
- uint8_t ucFlags;
-
- /* In case the stream buffer is going to be used as a message buffer
- * (that is, it will hold discrete messages with a little meta data that
- * says how big the next message is) check the buffer will be large enough
- * to hold at least one message. */
- if( xIsMessageBuffer == pdTRUE )
- {
- /* Is a message buffer but not statically allocated. */
- ucFlags = sbFLAGS_IS_MESSAGE_BUFFER;
- configASSERT( xBufferSizeBytes > sbBYTES_TO_STORE_MESSAGE_LENGTH );
- }
- else
- {
- /* Not a message buffer and not statically allocated. */
- ucFlags = 0;
- configASSERT( xBufferSizeBytes > 0 );
- }
-
- configASSERT( xTriggerLevelBytes <= xBufferSizeBytes );
-
- /* A trigger level of 0 would cause a waiting task to unblock even when
- * the buffer was empty. */
- if( xTriggerLevelBytes == ( size_t ) 0 )
- {
- xTriggerLevelBytes = ( size_t ) 1;
- }
-
- /* A stream buffer requires a StreamBuffer_t structure and a buffer.
- * Both are allocated in a single call to pvPortMalloc(). The
- * StreamBuffer_t structure is placed at the start of the allocated memory
- * and the buffer follows immediately after. The requested size is
- * incremented so the free space is returned as the user would expect -
- * this is a quirk of the implementation that means otherwise the free
- * space would be reported as one byte smaller than would be logically
- * expected. */
- if( xBufferSizeBytes < ( xBufferSizeBytes + 1 + sizeof( StreamBuffer_t ) ) )
- {
- xBufferSizeBytes++;
- pucAllocatedMemory = ( uint8_t * ) pvPortMalloc( xBufferSizeBytes + sizeof( StreamBuffer_t ) ); /*lint !e9079 malloc() only returns void*. */
- }
- else
- {
- pucAllocatedMemory = NULL;
- }
-
- if( pucAllocatedMemory != NULL )
- {
- prvInitialiseNewStreamBuffer( ( StreamBuffer_t * ) pucAllocatedMemory, /* Structure at the start of the allocated memory. */ /*lint !e9087 Safe cast as allocated memory is aligned. */ /*lint !e826 Area is not too small and alignment is guaranteed provided malloc() behaves as expected and returns aligned buffer. */
- pucAllocatedMemory + sizeof( StreamBuffer_t ), /* Storage area follows. */ /*lint !e9016 Indexing past structure valid for uint8_t pointer, also storage area has no alignment requirement. */
- xBufferSizeBytes,
- xTriggerLevelBytes,
- ucFlags );
-
- traceSTREAM_BUFFER_CREATE( ( ( StreamBuffer_t * ) pucAllocatedMemory ), xIsMessageBuffer );
- }
- else
- {
- traceSTREAM_BUFFER_CREATE_FAILED( xIsMessageBuffer );
- }
-
- return ( StreamBufferHandle_t ) pucAllocatedMemory; /*lint !e9087 !e826 Safe cast as allocated memory is aligned. */
- }
-
-#endif /* configSUPPORT_DYNAMIC_ALLOCATION */
-/*-----------------------------------------------------------*/
-
-#if ( configSUPPORT_STATIC_ALLOCATION == 1 )
-
- StreamBufferHandle_t xStreamBufferGenericCreateStatic( size_t xBufferSizeBytes,
- size_t xTriggerLevelBytes,
- BaseType_t xIsMessageBuffer,
- uint8_t * const pucStreamBufferStorageArea,
- StaticStreamBuffer_t * const pxStaticStreamBuffer )
- {
- StreamBuffer_t * const pxStreamBuffer = ( StreamBuffer_t * ) pxStaticStreamBuffer; /*lint !e740 !e9087 Safe cast as StaticStreamBuffer_t is opaque Streambuffer_t. */
- StreamBufferHandle_t xReturn;
- uint8_t ucFlags;
-
- configASSERT( pucStreamBufferStorageArea );
- configASSERT( pxStaticStreamBuffer );
- configASSERT( xTriggerLevelBytes <= xBufferSizeBytes );
-
- /* A trigger level of 0 would cause a waiting task to unblock even when
- * the buffer was empty. */
- if( xTriggerLevelBytes == ( size_t ) 0 )
- {
- xTriggerLevelBytes = ( size_t ) 1;
- }
-
- if( xIsMessageBuffer != pdFALSE )
- {
- /* Statically allocated message buffer. */
- ucFlags = sbFLAGS_IS_MESSAGE_BUFFER | sbFLAGS_IS_STATICALLY_ALLOCATED;
- }
- else
- {
- /* Statically allocated stream buffer. */
- ucFlags = sbFLAGS_IS_STATICALLY_ALLOCATED;
- }
-
- /* In case the stream buffer is going to be used as a message buffer
- * (that is, it will hold discrete messages with a little meta data that
- * says how big the next message is) check the buffer will be large enough
- * to hold at least one message. */
- configASSERT( xBufferSizeBytes > sbBYTES_TO_STORE_MESSAGE_LENGTH );
-
- #if ( configASSERT_DEFINED == 1 )
- {
- /* Sanity check that the size of the structure used to declare a
- * variable of type StaticStreamBuffer_t equals the size of the real
- * message buffer structure. */
- volatile size_t xSize = sizeof( StaticStreamBuffer_t );
- configASSERT( xSize == sizeof( StreamBuffer_t ) );
- } /*lint !e529 xSize is referenced is configASSERT() is defined. */
- #endif /* configASSERT_DEFINED */
-
- if( ( pucStreamBufferStorageArea != NULL ) && ( pxStaticStreamBuffer != NULL ) )
- {
- prvInitialiseNewStreamBuffer( pxStreamBuffer,
- pucStreamBufferStorageArea,
- xBufferSizeBytes,
- xTriggerLevelBytes,
- ucFlags );
-
- /* Remember this was statically allocated in case it is ever deleted
- * again. */
- pxStreamBuffer->ucFlags |= sbFLAGS_IS_STATICALLY_ALLOCATED;
-
- traceSTREAM_BUFFER_CREATE( pxStreamBuffer, xIsMessageBuffer );
-
- xReturn = ( StreamBufferHandle_t ) pxStaticStreamBuffer; /*lint !e9087 Data hiding requires cast to opaque type. */
- }
- else
- {
- xReturn = NULL;
- traceSTREAM_BUFFER_CREATE_STATIC_FAILED( xReturn, xIsMessageBuffer );
- }
-
- return xReturn;
- }
-
-#endif /* ( configSUPPORT_STATIC_ALLOCATION == 1 ) */
-/*-----------------------------------------------------------*/
-
-void vStreamBufferDelete( StreamBufferHandle_t xStreamBuffer )
-{
- StreamBuffer_t * pxStreamBuffer = xStreamBuffer;
-
- configASSERT( pxStreamBuffer );
-
- traceSTREAM_BUFFER_DELETE( xStreamBuffer );
-
- if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_STATICALLY_ALLOCATED ) == ( uint8_t ) pdFALSE )
- {
- #if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
- {
- /* Both the structure and the buffer were allocated using a single call
- * to pvPortMalloc(), hence only one call to vPortFree() is required. */
- vPortFree( ( void * ) pxStreamBuffer ); /*lint !e9087 Standard free() semantics require void *, plus pxStreamBuffer was allocated by pvPortMalloc(). */
- }
- #else
- {
- /* Should not be possible to get here, ucFlags must be corrupt.
- * Force an assert. */
- configASSERT( xStreamBuffer == ( StreamBufferHandle_t ) ~0 );
- }
- #endif
- }
- else
- {
- /* The structure and buffer were not allocated dynamically and cannot be
- * freed - just scrub the structure so future use will assert. */
- ( void ) memset( pxStreamBuffer, 0x00, sizeof( StreamBuffer_t ) );
- }
-}
-/*-----------------------------------------------------------*/
-
-BaseType_t xStreamBufferReset( StreamBufferHandle_t xStreamBuffer )
-{
- StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- BaseType_t xReturn = pdFAIL;
-
- #if ( configUSE_TRACE_FACILITY == 1 )
- UBaseType_t uxStreamBufferNumber;
- #endif
-
- configASSERT( pxStreamBuffer );
-
- #if ( configUSE_TRACE_FACILITY == 1 )
- {
- /* Store the stream buffer number so it can be restored after the
- * reset. */
- uxStreamBufferNumber = pxStreamBuffer->uxStreamBufferNumber;
- }
- #endif
-
- /* Can only reset a message buffer if there are no tasks blocked on it. */
- taskENTER_CRITICAL();
- {
- if( pxStreamBuffer->xTaskWaitingToReceive == NULL )
- {
- if( pxStreamBuffer->xTaskWaitingToSend == NULL )
- {
- prvInitialiseNewStreamBuffer( pxStreamBuffer,
- pxStreamBuffer->pucBuffer,
- pxStreamBuffer->xLength,
- pxStreamBuffer->xTriggerLevelBytes,
- pxStreamBuffer->ucFlags );
- xReturn = pdPASS;
-
- #if ( configUSE_TRACE_FACILITY == 1 )
- {
- pxStreamBuffer->uxStreamBufferNumber = uxStreamBufferNumber;
- }
- #endif
-
- traceSTREAM_BUFFER_RESET( xStreamBuffer );
- }
- }
- }
- taskEXIT_CRITICAL();
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-BaseType_t xStreamBufferSetTriggerLevel( StreamBufferHandle_t xStreamBuffer,
- size_t xTriggerLevel )
-{
- StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- BaseType_t xReturn;
-
- configASSERT( pxStreamBuffer );
-
- /* It is not valid for the trigger level to be 0. */
- if( xTriggerLevel == ( size_t ) 0 )
- {
- xTriggerLevel = ( size_t ) 1;
- }
-
- /* The trigger level is the number of bytes that must be in the stream
- * buffer before a task that is waiting for data is unblocked. */
- if( xTriggerLevel < pxStreamBuffer->xLength )
- {
- pxStreamBuffer->xTriggerLevelBytes = xTriggerLevel;
- xReturn = pdPASS;
- }
- else
- {
- xReturn = pdFALSE;
- }
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-size_t xStreamBufferSpacesAvailable( StreamBufferHandle_t xStreamBuffer )
-{
- const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- size_t xSpace;
-
- configASSERT( pxStreamBuffer );
-
- xSpace = pxStreamBuffer->xLength + pxStreamBuffer->xTail;
- xSpace -= pxStreamBuffer->xHead;
- xSpace -= ( size_t ) 1;
-
- if( xSpace >= pxStreamBuffer->xLength )
- {
- xSpace -= pxStreamBuffer->xLength;
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- return xSpace;
-}
-/*-----------------------------------------------------------*/
-
-size_t xStreamBufferBytesAvailable( StreamBufferHandle_t xStreamBuffer )
-{
- const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- size_t xReturn;
-
- configASSERT( pxStreamBuffer );
-
- xReturn = prvBytesInBuffer( pxStreamBuffer );
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-size_t xStreamBufferSend( StreamBufferHandle_t xStreamBuffer,
- const void * pvTxData,
- size_t xDataLengthBytes,
- TickType_t xTicksToWait )
-{
- StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- size_t xReturn, xSpace = 0;
- size_t xRequiredSpace = xDataLengthBytes;
- TimeOut_t xTimeOut;
- size_t xMaxReportedSpace = 0;
-
- configASSERT( pvTxData );
- configASSERT( pxStreamBuffer );
-
- /* The maximum amount of space a stream buffer will ever report is its length
- * minus 1. */
- xMaxReportedSpace = pxStreamBuffer->xLength - ( size_t ) 1;
-
- /* This send function is used to write to both message buffers and stream
- * buffers. If this is a message buffer then the space needed must be
- * increased by the amount of bytes needed to store the length of the
- * message. */
- if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
- {
- xRequiredSpace += sbBYTES_TO_STORE_MESSAGE_LENGTH;
-
- /* Overflow? */
- configASSERT( xRequiredSpace > xDataLengthBytes );
-
- /* If this is a message buffer then it must be possible to write the
- * whole message. */
- if( xRequiredSpace > xMaxReportedSpace )
- {
- /* The message would not fit even if the entire buffer was empty,
- * so don't wait for space. */
- xTicksToWait = ( TickType_t ) 0;
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
- }
- else
- {
- /* If this is a stream buffer then it is acceptable to write only part
- * of the message to the buffer. Cap the length to the total length of
- * the buffer. */
- if( xRequiredSpace > xMaxReportedSpace )
- {
- xRequiredSpace = xMaxReportedSpace;
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
- }
-
- if( xTicksToWait != ( TickType_t ) 0 )
- {
- vTaskSetTimeOutState( &xTimeOut );
-
- do
- {
- /* Wait until the required number of bytes are free in the message
- * buffer. */
- taskENTER_CRITICAL();
- {
- xSpace = xStreamBufferSpacesAvailable( pxStreamBuffer );
-
- if( xSpace < xRequiredSpace )
- {
- /* Clear notification state as going to wait for space. */
- ( void ) xTaskNotifyStateClear( NULL );
-
- /* Should only be one writer. */
- configASSERT( pxStreamBuffer->xTaskWaitingToSend == NULL );
- pxStreamBuffer->xTaskWaitingToSend = xTaskGetCurrentTaskHandle();
- }
- else
- {
- taskEXIT_CRITICAL();
- break;
- }
- }
- taskEXIT_CRITICAL();
-
- traceBLOCKING_ON_STREAM_BUFFER_SEND( xStreamBuffer );
- ( void ) xTaskNotifyWait( ( uint32_t ) 0, ( uint32_t ) 0, NULL, xTicksToWait );
- pxStreamBuffer->xTaskWaitingToSend = NULL;
- } while( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE );
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- if( xSpace == ( size_t ) 0 )
- {
- xSpace = xStreamBufferSpacesAvailable( pxStreamBuffer );
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- xReturn = prvWriteMessageToBuffer( pxStreamBuffer, pvTxData, xDataLengthBytes, xSpace, xRequiredSpace );
-
- if( xReturn > ( size_t ) 0 )
- {
- traceSTREAM_BUFFER_SEND( xStreamBuffer, xReturn );
-
- /* Was a task waiting for the data? */
- if( prvBytesInBuffer( pxStreamBuffer ) >= pxStreamBuffer->xTriggerLevelBytes )
- {
- sbSEND_COMPLETED( pxStreamBuffer );
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- traceSTREAM_BUFFER_SEND_FAILED( xStreamBuffer );
- }
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-size_t xStreamBufferSendFromISR( StreamBufferHandle_t xStreamBuffer,
- const void * pvTxData,
- size_t xDataLengthBytes,
- BaseType_t * const pxHigherPriorityTaskWoken )
-{
- StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- size_t xReturn, xSpace;
- size_t xRequiredSpace = xDataLengthBytes;
-
- configASSERT( pvTxData );
- configASSERT( pxStreamBuffer );
-
- /* This send function is used to write to both message buffers and stream
- * buffers. If this is a message buffer then the space needed must be
- * increased by the amount of bytes needed to store the length of the
- * message. */
- if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
- {
- xRequiredSpace += sbBYTES_TO_STORE_MESSAGE_LENGTH;
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- xSpace = xStreamBufferSpacesAvailable( pxStreamBuffer );
- xReturn = prvWriteMessageToBuffer( pxStreamBuffer, pvTxData, xDataLengthBytes, xSpace, xRequiredSpace );
-
- if( xReturn > ( size_t ) 0 )
- {
- /* Was a task waiting for the data? */
- if( prvBytesInBuffer( pxStreamBuffer ) >= pxStreamBuffer->xTriggerLevelBytes )
- {
- sbSEND_COMPLETE_FROM_ISR( pxStreamBuffer, pxHigherPriorityTaskWoken );
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- traceSTREAM_BUFFER_SEND_FROM_ISR( xStreamBuffer, xReturn );
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-static size_t prvWriteMessageToBuffer( StreamBuffer_t * const pxStreamBuffer,
- const void * pvTxData,
- size_t xDataLengthBytes,
- size_t xSpace,
- size_t xRequiredSpace )
-{
- BaseType_t xShouldWrite;
- size_t xReturn;
-
- if( xSpace == ( size_t ) 0 )
- {
- /* Doesn't matter if this is a stream buffer or a message buffer, there
- * is no space to write. */
- xShouldWrite = pdFALSE;
- }
- else if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) == ( uint8_t ) 0 )
- {
- /* This is a stream buffer, as opposed to a message buffer, so writing a
- * stream of bytes rather than discrete messages. Write as many bytes as
- * possible. */
- xShouldWrite = pdTRUE;
- xDataLengthBytes = configMIN( xDataLengthBytes, xSpace );
- }
- else if( xSpace >= xRequiredSpace )
- {
- /* This is a message buffer, as opposed to a stream buffer, and there
- * is enough space to write both the message length and the message itself
- * into the buffer. Start by writing the length of the data, the data
- * itself will be written later in this function. */
- xShouldWrite = pdTRUE;
- ( void ) prvWriteBytesToBuffer( pxStreamBuffer, ( const uint8_t * ) &( xDataLengthBytes ), sbBYTES_TO_STORE_MESSAGE_LENGTH );
- }
- else
- {
- /* There is space available, but not enough space. */
- xShouldWrite = pdFALSE;
- }
-
- if( xShouldWrite != pdFALSE )
- {
- /* Writes the data itself. */
- xReturn = prvWriteBytesToBuffer( pxStreamBuffer, ( const uint8_t * ) pvTxData, xDataLengthBytes ); /*lint !e9079 Storage buffer is implemented as uint8_t for ease of sizing, alignment and access. */
- }
- else
- {
- xReturn = 0;
- }
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-size_t xStreamBufferReceive( StreamBufferHandle_t xStreamBuffer,
- void * pvRxData,
- size_t xBufferLengthBytes,
- TickType_t xTicksToWait )
-{
- StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- size_t xReceivedLength = 0, xBytesAvailable, xBytesToStoreMessageLength;
-
- configASSERT( pvRxData );
- configASSERT( pxStreamBuffer );
-
- /* This receive function is used by both message buffers, which store
- * discrete messages, and stream buffers, which store a continuous stream of
- * bytes. Discrete messages include an additional
- * sbBYTES_TO_STORE_MESSAGE_LENGTH bytes that hold the length of the
- * message. */
- if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
- {
- xBytesToStoreMessageLength = sbBYTES_TO_STORE_MESSAGE_LENGTH;
- }
- else
- {
- xBytesToStoreMessageLength = 0;
- }
-
- if( xTicksToWait != ( TickType_t ) 0 )
- {
- /* Checking if there is data and clearing the notification state must be
- * performed atomically. */
- taskENTER_CRITICAL();
- {
- xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
-
- /* If this function was invoked by a message buffer read then
- * xBytesToStoreMessageLength holds the number of bytes used to hold
- * the length of the next discrete message. If this function was
- * invoked by a stream buffer read then xBytesToStoreMessageLength will
- * be 0. */
- if( xBytesAvailable <= xBytesToStoreMessageLength )
- {
- /* Clear notification state as going to wait for data. */
- ( void ) xTaskNotifyStateClear( NULL );
-
- /* Should only be one reader. */
- configASSERT( pxStreamBuffer->xTaskWaitingToReceive == NULL );
- pxStreamBuffer->xTaskWaitingToReceive = xTaskGetCurrentTaskHandle();
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
- }
- taskEXIT_CRITICAL();
-
- if( xBytesAvailable <= xBytesToStoreMessageLength )
- {
- /* Wait for data to be available. */
- traceBLOCKING_ON_STREAM_BUFFER_RECEIVE( xStreamBuffer );
- ( void ) xTaskNotifyWait( ( uint32_t ) 0, ( uint32_t ) 0, NULL, xTicksToWait );
- pxStreamBuffer->xTaskWaitingToReceive = NULL;
-
- /* Recheck the data available after blocking. */
- xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
- }
- else
- {
- xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
- }
-
- /* Whether receiving a discrete message (where xBytesToStoreMessageLength
- * holds the number of bytes used to store the message length) or a stream of
- * bytes (where xBytesToStoreMessageLength is zero), the number of bytes
- * available must be greater than xBytesToStoreMessageLength to be able to
- * read bytes from the buffer. */
- if( xBytesAvailable > xBytesToStoreMessageLength )
- {
- xReceivedLength = prvReadMessageFromBuffer( pxStreamBuffer, pvRxData, xBufferLengthBytes, xBytesAvailable, xBytesToStoreMessageLength );
-
- /* Was a task waiting for space in the buffer? */
- if( xReceivedLength != ( size_t ) 0 )
- {
- traceSTREAM_BUFFER_RECEIVE( xStreamBuffer, xReceivedLength );
- sbRECEIVE_COMPLETED( pxStreamBuffer );
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
- }
- else
- {
- traceSTREAM_BUFFER_RECEIVE_FAILED( xStreamBuffer );
- mtCOVERAGE_TEST_MARKER();
- }
-
- return xReceivedLength;
-}
-/*-----------------------------------------------------------*/
-
-size_t xStreamBufferNextMessageLengthBytes( StreamBufferHandle_t xStreamBuffer )
-{
- StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- size_t xReturn, xBytesAvailable, xOriginalTail;
- configMESSAGE_BUFFER_LENGTH_TYPE xTempReturn;
-
- configASSERT( pxStreamBuffer );
-
- /* Ensure the stream buffer is being used as a message buffer. */
- if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
- {
- xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
-
- if( xBytesAvailable > sbBYTES_TO_STORE_MESSAGE_LENGTH )
- {
- /* The number of bytes available is greater than the number of bytes
- * required to hold the length of the next message, so another message
- * is available. Return its length without removing the length bytes
- * from the buffer. A copy of the tail is stored so the buffer can be
- * returned to its prior state as the message is not actually being
- * removed from the buffer. */
- xOriginalTail = pxStreamBuffer->xTail;
- ( void ) prvReadBytesFromBuffer( pxStreamBuffer, ( uint8_t * ) &xTempReturn, sbBYTES_TO_STORE_MESSAGE_LENGTH, xBytesAvailable );
- xReturn = ( size_t ) xTempReturn;
- pxStreamBuffer->xTail = xOriginalTail;
- }
- else
- {
- /* The minimum amount of bytes in a message buffer is
- * ( sbBYTES_TO_STORE_MESSAGE_LENGTH + 1 ), so if xBytesAvailable is
- * less than sbBYTES_TO_STORE_MESSAGE_LENGTH the only other valid
- * value is 0. */
- configASSERT( xBytesAvailable == 0 );
- xReturn = 0;
- }
- }
- else
- {
- xReturn = 0;
- }
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-size_t xStreamBufferReceiveFromISR( StreamBufferHandle_t xStreamBuffer,
- void * pvRxData,
- size_t xBufferLengthBytes,
- BaseType_t * const pxHigherPriorityTaskWoken )
-{
- StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- size_t xReceivedLength = 0, xBytesAvailable, xBytesToStoreMessageLength;
-
- configASSERT( pvRxData );
- configASSERT( pxStreamBuffer );
-
- /* This receive function is used by both message buffers, which store
- * discrete messages, and stream buffers, which store a continuous stream of
- * bytes. Discrete messages include an additional
- * sbBYTES_TO_STORE_MESSAGE_LENGTH bytes that hold the length of the
- * message. */
- if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
- {
- xBytesToStoreMessageLength = sbBYTES_TO_STORE_MESSAGE_LENGTH;
- }
- else
- {
- xBytesToStoreMessageLength = 0;
- }
-
- xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
-
- /* Whether receiving a discrete message (where xBytesToStoreMessageLength
- * holds the number of bytes used to store the message length) or a stream of
- * bytes (where xBytesToStoreMessageLength is zero), the number of bytes
- * available must be greater than xBytesToStoreMessageLength to be able to
- * read bytes from the buffer. */
- if( xBytesAvailable > xBytesToStoreMessageLength )
- {
- xReceivedLength = prvReadMessageFromBuffer( pxStreamBuffer, pvRxData, xBufferLengthBytes, xBytesAvailable, xBytesToStoreMessageLength );
-
- /* Was a task waiting for space in the buffer? */
- if( xReceivedLength != ( size_t ) 0 )
- {
- sbRECEIVE_COMPLETED_FROM_ISR( pxStreamBuffer, pxHigherPriorityTaskWoken );
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- traceSTREAM_BUFFER_RECEIVE_FROM_ISR( xStreamBuffer, xReceivedLength );
-
- return xReceivedLength;
-}
-/*-----------------------------------------------------------*/
-
-static size_t prvReadMessageFromBuffer( StreamBuffer_t * pxStreamBuffer,
- void * pvRxData,
- size_t xBufferLengthBytes,
- size_t xBytesAvailable,
- size_t xBytesToStoreMessageLength )
-{
- size_t xOriginalTail, xReceivedLength, xNextMessageLength;
- configMESSAGE_BUFFER_LENGTH_TYPE xTempNextMessageLength;
-
- if( xBytesToStoreMessageLength != ( size_t ) 0 )
- {
- /* A discrete message is being received. First receive the length
- * of the message. A copy of the tail is stored so the buffer can be
- * returned to its prior state if the length of the message is too
- * large for the provided buffer. */
- xOriginalTail = pxStreamBuffer->xTail;
- ( void ) prvReadBytesFromBuffer( pxStreamBuffer, ( uint8_t * ) &xTempNextMessageLength, xBytesToStoreMessageLength, xBytesAvailable );
- xNextMessageLength = ( size_t ) xTempNextMessageLength;
-
- /* Reduce the number of bytes available by the number of bytes just
- * read out. */
- xBytesAvailable -= xBytesToStoreMessageLength;
-
- /* Check there is enough space in the buffer provided by the
- * user. */
- if( xNextMessageLength > xBufferLengthBytes )
- {
- /* The user has provided insufficient space to read the message
- * so return the buffer to its previous state (so the length of
- * the message is in the buffer again). */
- pxStreamBuffer->xTail = xOriginalTail;
- xNextMessageLength = 0;
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
- }
- else
- {
- /* A stream of bytes is being received (as opposed to a discrete
- * message), so read as many bytes as possible. */
- xNextMessageLength = xBufferLengthBytes;
- }
-
- /* Read the actual data. */
- xReceivedLength = prvReadBytesFromBuffer( pxStreamBuffer, ( uint8_t * ) pvRxData, xNextMessageLength, xBytesAvailable ); /*lint !e9079 Data storage area is implemented as uint8_t array for ease of sizing, indexing and alignment. */
-
- return xReceivedLength;
-}
-/*-----------------------------------------------------------*/
-
-BaseType_t xStreamBufferIsEmpty( StreamBufferHandle_t xStreamBuffer )
-{
- const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- BaseType_t xReturn;
- size_t xTail;
-
- configASSERT( pxStreamBuffer );
-
- /* True if no bytes are available. */
- xTail = pxStreamBuffer->xTail;
-
- if( pxStreamBuffer->xHead == xTail )
- {
- xReturn = pdTRUE;
- }
- else
- {
- xReturn = pdFALSE;
- }
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-BaseType_t xStreamBufferIsFull( StreamBufferHandle_t xStreamBuffer )
-{
- BaseType_t xReturn;
- size_t xBytesToStoreMessageLength;
- const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
-
- configASSERT( pxStreamBuffer );
-
- /* This generic version of the receive function is used by both message
- * buffers, which store discrete messages, and stream buffers, which store a
- * continuous stream of bytes. Discrete messages include an additional
- * sbBYTES_TO_STORE_MESSAGE_LENGTH bytes that hold the length of the message. */
- if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
- {
- xBytesToStoreMessageLength = sbBYTES_TO_STORE_MESSAGE_LENGTH;
- }
- else
- {
- xBytesToStoreMessageLength = 0;
- }
-
- /* True if the available space equals zero. */
- if( xStreamBufferSpacesAvailable( xStreamBuffer ) <= xBytesToStoreMessageLength )
- {
- xReturn = pdTRUE;
- }
- else
- {
- xReturn = pdFALSE;
- }
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-BaseType_t xStreamBufferSendCompletedFromISR( StreamBufferHandle_t xStreamBuffer,
- BaseType_t * pxHigherPriorityTaskWoken )
-{
- StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- BaseType_t xReturn;
- UBaseType_t uxSavedInterruptStatus;
-
- configASSERT( pxStreamBuffer );
-
- uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR();
- {
- if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL )
- {
- ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToReceive,
- ( uint32_t ) 0,
- eNoAction,
- pxHigherPriorityTaskWoken );
- ( pxStreamBuffer )->xTaskWaitingToReceive = NULL;
- xReturn = pdTRUE;
- }
- else
- {
- xReturn = pdFALSE;
- }
- }
- portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-BaseType_t xStreamBufferReceiveCompletedFromISR( StreamBufferHandle_t xStreamBuffer,
- BaseType_t * pxHigherPriorityTaskWoken )
-{
- StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
- BaseType_t xReturn;
- UBaseType_t uxSavedInterruptStatus;
-
- configASSERT( pxStreamBuffer );
-
- uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR();
- {
- if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL )
- {
- ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToSend,
- ( uint32_t ) 0,
- eNoAction,
- pxHigherPriorityTaskWoken );
- ( pxStreamBuffer )->xTaskWaitingToSend = NULL;
- xReturn = pdTRUE;
- }
- else
- {
- xReturn = pdFALSE;
- }
- }
- portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
-
- return xReturn;
-}
-/*-----------------------------------------------------------*/
-
-static size_t prvWriteBytesToBuffer( StreamBuffer_t * const pxStreamBuffer,
- const uint8_t * pucData,
- size_t xCount )
-{
- size_t xNextHead, xFirstLength;
-
- configASSERT( xCount > ( size_t ) 0 );
-
- xNextHead = pxStreamBuffer->xHead;
-
- /* Calculate the number of bytes that can be added in the first write -
- * which may be less than the total number of bytes that need to be added if
- * the buffer will wrap back to the beginning. */
- xFirstLength = configMIN( pxStreamBuffer->xLength - xNextHead, xCount );
-
- /* Write as many bytes as can be written in the first write. */
- configASSERT( ( xNextHead + xFirstLength ) <= pxStreamBuffer->xLength );
- ( void ) memcpy( ( void * ) ( &( pxStreamBuffer->pucBuffer[ xNextHead ] ) ), ( const void * ) pucData, xFirstLength ); /*lint !e9087 memcpy() requires void *. */
-
- /* If the number of bytes written was less than the number that could be
- * written in the first write... */
- if( xCount > xFirstLength )
- {
- /* ...then write the remaining bytes to the start of the buffer. */
- configASSERT( ( xCount - xFirstLength ) <= pxStreamBuffer->xLength );
- ( void ) memcpy( ( void * ) pxStreamBuffer->pucBuffer, ( const void * ) &( pucData[ xFirstLength ] ), xCount - xFirstLength ); /*lint !e9087 memcpy() requires void *. */
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- xNextHead += xCount;
-
- if( xNextHead >= pxStreamBuffer->xLength )
- {
- xNextHead -= pxStreamBuffer->xLength;
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- pxStreamBuffer->xHead = xNextHead;
-
- return xCount;
-}
-/*-----------------------------------------------------------*/
-
-static size_t prvReadBytesFromBuffer( StreamBuffer_t * pxStreamBuffer,
- uint8_t * pucData,
- size_t xMaxCount,
- size_t xBytesAvailable )
-{
- size_t xCount, xFirstLength, xNextTail;
-
- /* Use the minimum of the wanted bytes and the available bytes. */
- xCount = configMIN( xBytesAvailable, xMaxCount );
-
- if( xCount > ( size_t ) 0 )
- {
- xNextTail = pxStreamBuffer->xTail;
-
- /* Calculate the number of bytes that can be read - which may be
- * less than the number wanted if the data wraps around to the start of
- * the buffer. */
- xFirstLength = configMIN( pxStreamBuffer->xLength - xNextTail, xCount );
-
- /* Obtain the number of bytes it is possible to obtain in the first
- * read. Asserts check bounds of read and write. */
- configASSERT( xFirstLength <= xMaxCount );
- configASSERT( ( xNextTail + xFirstLength ) <= pxStreamBuffer->xLength );
- ( void ) memcpy( ( void * ) pucData, ( const void * ) &( pxStreamBuffer->pucBuffer[ xNextTail ] ), xFirstLength ); /*lint !e9087 memcpy() requires void *. */
-
- /* If the total number of wanted bytes is greater than the number
- * that could be read in the first read... */
- if( xCount > xFirstLength )
- {
- /*...then read the remaining bytes from the start of the buffer. */
- configASSERT( xCount <= xMaxCount );
- ( void ) memcpy( ( void * ) &( pucData[ xFirstLength ] ), ( void * ) ( pxStreamBuffer->pucBuffer ), xCount - xFirstLength ); /*lint !e9087 memcpy() requires void *. */
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- /* Move the tail pointer to effectively remove the data read from
- * the buffer. */
- xNextTail += xCount;
-
- if( xNextTail >= pxStreamBuffer->xLength )
- {
- xNextTail -= pxStreamBuffer->xLength;
- }
-
- pxStreamBuffer->xTail = xNextTail;
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- return xCount;
-}
-/*-----------------------------------------------------------*/
-
-static size_t prvBytesInBuffer( const StreamBuffer_t * const pxStreamBuffer )
-{
-/* Returns the distance between xTail and xHead. */
- size_t xCount;
-
- xCount = pxStreamBuffer->xLength + pxStreamBuffer->xHead;
- xCount -= pxStreamBuffer->xTail;
-
- if( xCount >= pxStreamBuffer->xLength )
- {
- xCount -= pxStreamBuffer->xLength;
- }
- else
- {
- mtCOVERAGE_TEST_MARKER();
- }
-
- return xCount;
-}
-/*-----------------------------------------------------------*/
-
-static void prvInitialiseNewStreamBuffer( StreamBuffer_t * const pxStreamBuffer,
- uint8_t * const pucBuffer,
- size_t xBufferSizeBytes,
- size_t xTriggerLevelBytes,
- uint8_t ucFlags )
-{
- /* Assert here is deliberately writing to the entire buffer to ensure it can
- * be written to without generating exceptions, and is setting the buffer to a
- * known value to assist in development/debugging. */
- #if ( configASSERT_DEFINED == 1 )
- {
- /* The value written just has to be identifiable when looking at the
- * memory. Don't use 0xA5 as that is the stack fill value and could
- * result in confusion as to what is actually being observed. */
- const BaseType_t xWriteValue = 0x55;
- configASSERT( memset( pucBuffer, ( int ) xWriteValue, xBufferSizeBytes ) == pucBuffer );
- } /*lint !e529 !e438 xWriteValue is only used if configASSERT() is defined. */
- #endif
-
- ( void ) memset( ( void * ) pxStreamBuffer, 0x00, sizeof( StreamBuffer_t ) ); /*lint !e9087 memset() requires void *. */
- pxStreamBuffer->pucBuffer = pucBuffer;
- pxStreamBuffer->xLength = xBufferSizeBytes;
- pxStreamBuffer->xTriggerLevelBytes = xTriggerLevelBytes;
- pxStreamBuffer->ucFlags = ucFlags;
-}
-
-#if ( configUSE_TRACE_FACILITY == 1 )
-
- UBaseType_t uxStreamBufferGetStreamBufferNumber( StreamBufferHandle_t xStreamBuffer )
- {
- return xStreamBuffer->uxStreamBufferNumber;
- }
-
-#endif /* configUSE_TRACE_FACILITY */
-/*-----------------------------------------------------------*/
-
-#if ( configUSE_TRACE_FACILITY == 1 )
-
- void vStreamBufferSetStreamBufferNumber( StreamBufferHandle_t xStreamBuffer,
- UBaseType_t uxStreamBufferNumber )
- {
- xStreamBuffer->uxStreamBufferNumber = uxStreamBufferNumber;
- }
-
-#endif /* configUSE_TRACE_FACILITY */
-/*-----------------------------------------------------------*/
-
-#if ( configUSE_TRACE_FACILITY == 1 )
-
- uint8_t ucStreamBufferGetStreamBufferType( StreamBufferHandle_t xStreamBuffer )
- {
- return( xStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER );
- }
-
-#endif /* configUSE_TRACE_FACILITY */
-/*-----------------------------------------------------------*/
+/*
+ * FreeRTOS Kernel V10.4.3
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * https://www.FreeRTOS.org
+ * https://github.com/FreeRTOS
+ *
+ */
+
+/* Standard includes. */
+#include <stdint.h>
+#include <string.h>
+
+/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
+ * all the API functions to use the MPU wrappers. That should only be done when
+ * task.h is included from an application file. */
+#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
+
+/* FreeRTOS includes. */
+#include "FreeRTOS.h"
+#include "task.h"
+#include "stream_buffer.h"
+
+#if ( configUSE_TASK_NOTIFICATIONS != 1 )
+ #error configUSE_TASK_NOTIFICATIONS must be set to 1 to build stream_buffer.c
+#endif
+
+/* Lint e961, e9021 and e750 are suppressed as a MISRA exception justified
+ * because the MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined
+ * for the header files above, but not in this file, in order to generate the
+ * correct privileged Vs unprivileged linkage and placement. */
+#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e961 !e750 !e9021. */
+
+/* If the user has not provided application specific Rx notification macros,
+ * or #defined the notification macros away, then provide default implementations
+ * that uses task notifications. */
+/*lint -save -e9026 Function like macros allowed and needed here so they can be overridden. */
+#ifndef sbRECEIVE_COMPLETED
+ #define sbRECEIVE_COMPLETED( pxStreamBuffer ) \
+ vTaskSuspendAll(); \
+ { \
+ if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL ) \
+ { \
+ ( void ) xTaskNotify( ( pxStreamBuffer )->xTaskWaitingToSend, \
+ ( uint32_t ) 0, \
+ eNoAction ); \
+ ( pxStreamBuffer )->xTaskWaitingToSend = NULL; \
+ } \
+ } \
+ ( void ) xTaskResumeAll();
+#endif /* sbRECEIVE_COMPLETED */
+
+#ifndef sbRECEIVE_COMPLETED_FROM_ISR
+ #define sbRECEIVE_COMPLETED_FROM_ISR( pxStreamBuffer, \
+ pxHigherPriorityTaskWoken ) \
+ { \
+ UBaseType_t uxSavedInterruptStatus; \
+ \
+ uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR(); \
+ { \
+ if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL ) \
+ { \
+ ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToSend, \
+ ( uint32_t ) 0, \
+ eNoAction, \
+ pxHigherPriorityTaskWoken ); \
+ ( pxStreamBuffer )->xTaskWaitingToSend = NULL; \
+ } \
+ } \
+ portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus ); \
+ }
+#endif /* sbRECEIVE_COMPLETED_FROM_ISR */
+
+/* If the user has not provided an application specific Tx notification macro,
+ * or #defined the notification macro away, them provide a default implementation
+ * that uses task notifications. */
+#ifndef sbSEND_COMPLETED
+ #define sbSEND_COMPLETED( pxStreamBuffer ) \
+ vTaskSuspendAll(); \
+ { \
+ if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL ) \
+ { \
+ ( void ) xTaskNotify( ( pxStreamBuffer )->xTaskWaitingToReceive, \
+ ( uint32_t ) 0, \
+ eNoAction ); \
+ ( pxStreamBuffer )->xTaskWaitingToReceive = NULL; \
+ } \
+ } \
+ ( void ) xTaskResumeAll();
+#endif /* sbSEND_COMPLETED */
+
+#ifndef sbSEND_COMPLETE_FROM_ISR
+ #define sbSEND_COMPLETE_FROM_ISR( pxStreamBuffer, pxHigherPriorityTaskWoken ) \
+ { \
+ UBaseType_t uxSavedInterruptStatus; \
+ \
+ uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR(); \
+ { \
+ if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL ) \
+ { \
+ ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToReceive, \
+ ( uint32_t ) 0, \
+ eNoAction, \
+ pxHigherPriorityTaskWoken ); \
+ ( pxStreamBuffer )->xTaskWaitingToReceive = NULL; \
+ } \
+ } \
+ portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus ); \
+ }
+#endif /* sbSEND_COMPLETE_FROM_ISR */
+/*lint -restore (9026) */
+
+/* The number of bytes used to hold the length of a message in the buffer. */
+#define sbBYTES_TO_STORE_MESSAGE_LENGTH ( sizeof( configMESSAGE_BUFFER_LENGTH_TYPE ) )
+
+/* Bits stored in the ucFlags field of the stream buffer. */
+#define sbFLAGS_IS_MESSAGE_BUFFER ( ( uint8_t ) 1 ) /* Set if the stream buffer was created as a message buffer, in which case it holds discrete messages rather than a stream. */
+#define sbFLAGS_IS_STATICALLY_ALLOCATED ( ( uint8_t ) 2 ) /* Set if the stream buffer was created using statically allocated memory. */
+
+/*-----------------------------------------------------------*/
+
+/* Structure that hold state information on the buffer. */
+typedef struct StreamBufferDef_t /*lint !e9058 Style convention uses tag. */
+{
+ volatile size_t xTail; /* Index to the next item to read within the buffer. */
+ volatile size_t xHead; /* Index to the next item to write within the buffer. */
+ size_t xLength; /* The length of the buffer pointed to by pucBuffer. */
+ size_t xTriggerLevelBytes; /* The number of bytes that must be in the stream buffer before a task that is waiting for data is unblocked. */
+ volatile TaskHandle_t xTaskWaitingToReceive; /* Holds the handle of a task waiting for data, or NULL if no tasks are waiting. */
+ volatile TaskHandle_t xTaskWaitingToSend; /* Holds the handle of a task waiting to send data to a message buffer that is full. */
+ uint8_t * pucBuffer; /* Points to the buffer itself - that is - the RAM that stores the data passed through the buffer. */
+ uint8_t ucFlags;
+
+ #if ( configUSE_TRACE_FACILITY == 1 )
+ UBaseType_t uxStreamBufferNumber; /* Used for tracing purposes. */
+ #endif
+} StreamBuffer_t;
+
+/*
+ * The number of bytes available to be read from the buffer.
+ */
+static size_t prvBytesInBuffer( const StreamBuffer_t * const pxStreamBuffer ) PRIVILEGED_FUNCTION;
+
+/*
+ * Add xCount bytes from pucData into the pxStreamBuffer's data storage area.
+ * This function does not update the buffer's xHead pointer, so multiple writes
+ * may be chained together "atomically". This is useful for Message Buffers where
+ * the length and data bytes are written in two separate chunks, and we don't want
+ * the reader to see the buffer as having grown until after all data is copied over.
+ * This function takes a custom xHead value to indicate where to write to (necessary
+ * for chaining) and returns the the resulting xHead position.
+ * To mark the write as complete, manually set the buffer's xHead field with the
+ * returned xHead from this function.
+ */
+static size_t prvWriteBytesToBuffer( StreamBuffer_t * const pxStreamBuffer,
+ const uint8_t * pucData,
+ size_t xCount,
+ size_t xHead ) PRIVILEGED_FUNCTION;
+
+/*
+ * If the stream buffer is being used as a message buffer, then reads an entire
+ * message out of the buffer. If the stream buffer is being used as a stream
+ * buffer then read as many bytes as possible from the buffer.
+ * prvReadBytesFromBuffer() is called to actually extract the bytes from the
+ * buffer's data storage area.
+ */
+static size_t prvReadMessageFromBuffer( StreamBuffer_t * pxStreamBuffer,
+ void * pvRxData,
+ size_t xBufferLengthBytes,
+ size_t xBytesAvailable ) PRIVILEGED_FUNCTION;
+
+/*
+ * If the stream buffer is being used as a message buffer, then writes an entire
+ * message to the buffer. If the stream buffer is being used as a stream
+ * buffer then write as many bytes as possible to the buffer.
+ * prvWriteBytestoBuffer() is called to actually send the bytes to the buffer's
+ * data storage area.
+ */
+static size_t prvWriteMessageToBuffer( StreamBuffer_t * const pxStreamBuffer,
+ const void * pvTxData,
+ size_t xDataLengthBytes,
+ size_t xSpace,
+ size_t xRequiredSpace ) PRIVILEGED_FUNCTION;
+
+/*
+ * Copies xCount bytes from the pxStreamBuffer's data storage area to pucData.
+ * This function does not update the buffer's xTail pointer, so multiple reads
+ * may be chained together "atomically". This is useful for Message Buffers where
+ * the length and data bytes are read in two separate chunks, and we don't want
+ * the writer to see the buffer as having more free space until after all data is
+ * copied over, especially if we have to abort the read due to insufficient receiving space.
+ * This function takes a custom xTail value to indicate where to read from (necessary
+ * for chaining) and returns the the resulting xTail position.
+ * To mark the read as complete, manually set the buffer's xTail field with the
+ * returned xTail from this function.
+ */
+static size_t prvReadBytesFromBuffer( StreamBuffer_t * pxStreamBuffer,
+ uint8_t * pucData,
+ size_t xCount,
+ size_t xTail ) PRIVILEGED_FUNCTION;
+
+/*
+ * Called by both pxStreamBufferCreate() and pxStreamBufferCreateStatic() to
+ * initialise the members of the newly created stream buffer structure.
+ */
+static void prvInitialiseNewStreamBuffer( StreamBuffer_t * const pxStreamBuffer,
+ uint8_t * const pucBuffer,
+ size_t xBufferSizeBytes,
+ size_t xTriggerLevelBytes,
+ uint8_t ucFlags ) PRIVILEGED_FUNCTION;
+
+/*-----------------------------------------------------------*/
+
+#if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
+
+ StreamBufferHandle_t xStreamBufferGenericCreate( size_t xBufferSizeBytes,
+ size_t xTriggerLevelBytes,
+ BaseType_t xIsMessageBuffer )
+ {
+ uint8_t * pucAllocatedMemory;
+ uint8_t ucFlags;
+
+ /* In case the stream buffer is going to be used as a message buffer
+ * (that is, it will hold discrete messages with a little meta data that
+ * says how big the next message is) check the buffer will be large enough
+ * to hold at least one message. */
+ if( xIsMessageBuffer == pdTRUE )
+ {
+ /* Is a message buffer but not statically allocated. */
+ ucFlags = sbFLAGS_IS_MESSAGE_BUFFER;
+ configASSERT( xBufferSizeBytes > sbBYTES_TO_STORE_MESSAGE_LENGTH );
+ }
+ else
+ {
+ /* Not a message buffer and not statically allocated. */
+ ucFlags = 0;
+ configASSERT( xBufferSizeBytes > 0 );
+ }
+
+ configASSERT( xTriggerLevelBytes <= xBufferSizeBytes );
+
+ /* A trigger level of 0 would cause a waiting task to unblock even when
+ * the buffer was empty. */
+ if( xTriggerLevelBytes == ( size_t ) 0 )
+ {
+ xTriggerLevelBytes = ( size_t ) 1;
+ }
+
+ /* A stream buffer requires a StreamBuffer_t structure and a buffer.
+ * Both are allocated in a single call to pvPortMalloc(). The
+ * StreamBuffer_t structure is placed at the start of the allocated memory
+ * and the buffer follows immediately after. The requested size is
+ * incremented so the free space is returned as the user would expect -
+ * this is a quirk of the implementation that means otherwise the free
+ * space would be reported as one byte smaller than would be logically
+ * expected. */
+ if( xBufferSizeBytes < ( xBufferSizeBytes + 1 + sizeof( StreamBuffer_t ) ) )
+ {
+ xBufferSizeBytes++;
+ pucAllocatedMemory = ( uint8_t * ) pvPortMalloc( xBufferSizeBytes + sizeof( StreamBuffer_t ) ); /*lint !e9079 malloc() only returns void*. */
+ }
+ else
+ {
+ pucAllocatedMemory = NULL;
+ }
+
+ if( pucAllocatedMemory != NULL )
+ {
+ prvInitialiseNewStreamBuffer( ( StreamBuffer_t * ) pucAllocatedMemory, /* Structure at the start of the allocated memory. */ /*lint !e9087 Safe cast as allocated memory is aligned. */ /*lint !e826 Area is not too small and alignment is guaranteed provided malloc() behaves as expected and returns aligned buffer. */
+ pucAllocatedMemory + sizeof( StreamBuffer_t ), /* Storage area follows. */ /*lint !e9016 Indexing past structure valid for uint8_t pointer, also storage area has no alignment requirement. */
+ xBufferSizeBytes,
+ xTriggerLevelBytes,
+ ucFlags );
+
+ traceSTREAM_BUFFER_CREATE( ( ( StreamBuffer_t * ) pucAllocatedMemory ), xIsMessageBuffer );
+ }
+ else
+ {
+ traceSTREAM_BUFFER_CREATE_FAILED( xIsMessageBuffer );
+ }
+
+ return ( StreamBufferHandle_t ) pucAllocatedMemory; /*lint !e9087 !e826 Safe cast as allocated memory is aligned. */
+ }
+
+#endif /* configSUPPORT_DYNAMIC_ALLOCATION */
+/*-----------------------------------------------------------*/
+
+#if ( configSUPPORT_STATIC_ALLOCATION == 1 )
+
+ StreamBufferHandle_t xStreamBufferGenericCreateStatic( size_t xBufferSizeBytes,
+ size_t xTriggerLevelBytes,
+ BaseType_t xIsMessageBuffer,
+ uint8_t * const pucStreamBufferStorageArea,
+ StaticStreamBuffer_t * const pxStaticStreamBuffer )
+ {
+ StreamBuffer_t * const pxStreamBuffer = ( StreamBuffer_t * ) pxStaticStreamBuffer; /*lint !e740 !e9087 Safe cast as StaticStreamBuffer_t is opaque Streambuffer_t. */
+ StreamBufferHandle_t xReturn;
+ uint8_t ucFlags;
+
+ configASSERT( pucStreamBufferStorageArea );
+ configASSERT( pxStaticStreamBuffer );
+ configASSERT( xTriggerLevelBytes <= xBufferSizeBytes );
+
+ /* A trigger level of 0 would cause a waiting task to unblock even when
+ * the buffer was empty. */
+ if( xTriggerLevelBytes == ( size_t ) 0 )
+ {
+ xTriggerLevelBytes = ( size_t ) 1;
+ }
+
+ if( xIsMessageBuffer != pdFALSE )
+ {
+ /* Statically allocated message buffer. */
+ ucFlags = sbFLAGS_IS_MESSAGE_BUFFER | sbFLAGS_IS_STATICALLY_ALLOCATED;
+ }
+ else
+ {
+ /* Statically allocated stream buffer. */
+ ucFlags = sbFLAGS_IS_STATICALLY_ALLOCATED;
+ }
+
+ /* In case the stream buffer is going to be used as a message buffer
+ * (that is, it will hold discrete messages with a little meta data that
+ * says how big the next message is) check the buffer will be large enough
+ * to hold at least one message. */
+ configASSERT( xBufferSizeBytes > sbBYTES_TO_STORE_MESSAGE_LENGTH );
+
+ #if ( configASSERT_DEFINED == 1 )
+ {
+ /* Sanity check that the size of the structure used to declare a
+ * variable of type StaticStreamBuffer_t equals the size of the real
+ * message buffer structure. */
+ volatile size_t xSize = sizeof( StaticStreamBuffer_t );
+ configASSERT( xSize == sizeof( StreamBuffer_t ) );
+ } /*lint !e529 xSize is referenced is configASSERT() is defined. */
+ #endif /* configASSERT_DEFINED */
+
+ if( ( pucStreamBufferStorageArea != NULL ) && ( pxStaticStreamBuffer != NULL ) )
+ {
+ prvInitialiseNewStreamBuffer( pxStreamBuffer,
+ pucStreamBufferStorageArea,
+ xBufferSizeBytes,
+ xTriggerLevelBytes,
+ ucFlags );
+
+ /* Remember this was statically allocated in case it is ever deleted
+ * again. */
+ pxStreamBuffer->ucFlags |= sbFLAGS_IS_STATICALLY_ALLOCATED;
+
+ traceSTREAM_BUFFER_CREATE( pxStreamBuffer, xIsMessageBuffer );
+
+ xReturn = ( StreamBufferHandle_t ) pxStaticStreamBuffer; /*lint !e9087 Data hiding requires cast to opaque type. */
+ }
+ else
+ {
+ xReturn = NULL;
+ traceSTREAM_BUFFER_CREATE_STATIC_FAILED( xReturn, xIsMessageBuffer );
+ }
+
+ return xReturn;
+ }
+
+#endif /* ( configSUPPORT_STATIC_ALLOCATION == 1 ) */
+/*-----------------------------------------------------------*/
+
+void vStreamBufferDelete( StreamBufferHandle_t xStreamBuffer )
+{
+ StreamBuffer_t * pxStreamBuffer = xStreamBuffer;
+
+ configASSERT( pxStreamBuffer );
+
+ traceSTREAM_BUFFER_DELETE( xStreamBuffer );
+
+ if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_STATICALLY_ALLOCATED ) == ( uint8_t ) pdFALSE )
+ {
+ #if ( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
+ {
+ /* Both the structure and the buffer were allocated using a single call
+ * to pvPortMalloc(), hence only one call to vPortFree() is required. */
+ vPortFree( ( void * ) pxStreamBuffer ); /*lint !e9087 Standard free() semantics require void *, plus pxStreamBuffer was allocated by pvPortMalloc(). */
+ }
+ #else
+ {
+ /* Should not be possible to get here, ucFlags must be corrupt.
+ * Force an assert. */
+ configASSERT( xStreamBuffer == ( StreamBufferHandle_t ) ~0 );
+ }
+ #endif
+ }
+ else
+ {
+ /* The structure and buffer were not allocated dynamically and cannot be
+ * freed - just scrub the structure so future use will assert. */
+ ( void ) memset( pxStreamBuffer, 0x00, sizeof( StreamBuffer_t ) );
+ }
+}
+/*-----------------------------------------------------------*/
+
+BaseType_t xStreamBufferReset( StreamBufferHandle_t xStreamBuffer )
+{
+ StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ BaseType_t xReturn = pdFAIL;
+
+ #if ( configUSE_TRACE_FACILITY == 1 )
+ UBaseType_t uxStreamBufferNumber;
+ #endif
+
+ configASSERT( pxStreamBuffer );
+
+ #if ( configUSE_TRACE_FACILITY == 1 )
+ {
+ /* Store the stream buffer number so it can be restored after the
+ * reset. */
+ uxStreamBufferNumber = pxStreamBuffer->uxStreamBufferNumber;
+ }
+ #endif
+
+ /* Can only reset a message buffer if there are no tasks blocked on it. */
+ taskENTER_CRITICAL();
+ {
+ if( pxStreamBuffer->xTaskWaitingToReceive == NULL )
+ {
+ if( pxStreamBuffer->xTaskWaitingToSend == NULL )
+ {
+ prvInitialiseNewStreamBuffer( pxStreamBuffer,
+ pxStreamBuffer->pucBuffer,
+ pxStreamBuffer->xLength,
+ pxStreamBuffer->xTriggerLevelBytes,
+ pxStreamBuffer->ucFlags );
+ xReturn = pdPASS;
+
+ #if ( configUSE_TRACE_FACILITY == 1 )
+ {
+ pxStreamBuffer->uxStreamBufferNumber = uxStreamBufferNumber;
+ }
+ #endif
+
+ traceSTREAM_BUFFER_RESET( xStreamBuffer );
+ }
+ }
+ }
+ taskEXIT_CRITICAL();
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+BaseType_t xStreamBufferSetTriggerLevel( StreamBufferHandle_t xStreamBuffer,
+ size_t xTriggerLevel )
+{
+ StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ BaseType_t xReturn;
+
+ configASSERT( pxStreamBuffer );
+
+ /* It is not valid for the trigger level to be 0. */
+ if( xTriggerLevel == ( size_t ) 0 )
+ {
+ xTriggerLevel = ( size_t ) 1;
+ }
+
+ /* The trigger level is the number of bytes that must be in the stream
+ * buffer before a task that is waiting for data is unblocked. */
+ if( xTriggerLevel < pxStreamBuffer->xLength )
+ {
+ pxStreamBuffer->xTriggerLevelBytes = xTriggerLevel;
+ xReturn = pdPASS;
+ }
+ else
+ {
+ xReturn = pdFALSE;
+ }
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+size_t xStreamBufferSpacesAvailable( StreamBufferHandle_t xStreamBuffer )
+{
+ const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ size_t xSpace;
+ volatile size_t xOriginalTail;
+
+ configASSERT( pxStreamBuffer );
+
+ /* The code below reads xTail and then xHead. This is safe if the stream
+ buffer is updated once between the two reads - but not if the stream buffer
+ is updated more than once between the two reads - hence the loop. */
+ do
+ {
+ xOriginalTail = pxStreamBuffer->xTail;
+ xSpace = pxStreamBuffer->xLength + pxStreamBuffer->xTail;
+ xSpace -= pxStreamBuffer->xHead;
+ } while( xOriginalTail != pxStreamBuffer->xTail );
+ xSpace -= ( size_t ) 1;
+
+ if( xSpace >= pxStreamBuffer->xLength )
+ {
+ xSpace -= pxStreamBuffer->xLength;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ return xSpace;
+}
+/*-----------------------------------------------------------*/
+
+size_t xStreamBufferBytesAvailable( StreamBufferHandle_t xStreamBuffer )
+{
+ const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ size_t xReturn;
+
+ configASSERT( pxStreamBuffer );
+
+ xReturn = prvBytesInBuffer( pxStreamBuffer );
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+size_t xStreamBufferSend( StreamBufferHandle_t xStreamBuffer,
+ const void * pvTxData,
+ size_t xDataLengthBytes,
+ TickType_t xTicksToWait )
+{
+ StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ size_t xReturn, xSpace = 0;
+ size_t xRequiredSpace = xDataLengthBytes;
+ TimeOut_t xTimeOut;
+ size_t xMaxReportedSpace = 0;
+
+ configASSERT( pvTxData );
+ configASSERT( pxStreamBuffer );
+
+ /* The maximum amount of space a stream buffer will ever report is its length
+ * minus 1. */
+ xMaxReportedSpace = pxStreamBuffer->xLength - ( size_t ) 1;
+
+ /* This send function is used to write to both message buffers and stream
+ * buffers. If this is a message buffer then the space needed must be
+ * increased by the amount of bytes needed to store the length of the
+ * message. */
+ if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
+ {
+ xRequiredSpace += sbBYTES_TO_STORE_MESSAGE_LENGTH;
+
+ /* Overflow? */
+ configASSERT( xRequiredSpace > xDataLengthBytes );
+
+ /* If this is a message buffer then it must be possible to write the
+ * whole message. */
+ if( xRequiredSpace > xMaxReportedSpace )
+ {
+ /* The message would not fit even if the entire buffer was empty,
+ * so don't wait for space. */
+ xTicksToWait = ( TickType_t ) 0;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ /* If this is a stream buffer then it is acceptable to write only part
+ * of the message to the buffer. Cap the length to the total length of
+ * the buffer. */
+ if( xRequiredSpace > xMaxReportedSpace )
+ {
+ xRequiredSpace = xMaxReportedSpace;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+
+ if( xTicksToWait != ( TickType_t ) 0 )
+ {
+ vTaskSetTimeOutState( &xTimeOut );
+
+ do
+ {
+ /* Wait until the required number of bytes are free in the message
+ * buffer. */
+ taskENTER_CRITICAL();
+ {
+ xSpace = xStreamBufferSpacesAvailable( pxStreamBuffer );
+
+ if( xSpace < xRequiredSpace )
+ {
+ /* Clear notification state as going to wait for space. */
+ ( void ) xTaskNotifyStateClear( NULL );
+
+ /* Should only be one writer. */
+ configASSERT( pxStreamBuffer->xTaskWaitingToSend == NULL );
+ pxStreamBuffer->xTaskWaitingToSend = xTaskGetCurrentTaskHandle();
+ }
+ else
+ {
+ taskEXIT_CRITICAL();
+ break;
+ }
+ }
+ taskEXIT_CRITICAL();
+
+ traceBLOCKING_ON_STREAM_BUFFER_SEND( xStreamBuffer );
+ ( void ) xTaskNotifyWait( ( uint32_t ) 0, ( uint32_t ) 0, NULL, xTicksToWait );
+ pxStreamBuffer->xTaskWaitingToSend = NULL;
+ } while( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE );
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ if( xSpace == ( size_t ) 0 )
+ {
+ xSpace = xStreamBufferSpacesAvailable( pxStreamBuffer );
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ xReturn = prvWriteMessageToBuffer( pxStreamBuffer, pvTxData, xDataLengthBytes, xSpace, xRequiredSpace );
+
+ if( xReturn > ( size_t ) 0 )
+ {
+ traceSTREAM_BUFFER_SEND( xStreamBuffer, xReturn );
+
+ /* Was a task waiting for the data? */
+ if( prvBytesInBuffer( pxStreamBuffer ) >= pxStreamBuffer->xTriggerLevelBytes )
+ {
+ sbSEND_COMPLETED( pxStreamBuffer );
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ traceSTREAM_BUFFER_SEND_FAILED( xStreamBuffer );
+ }
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+size_t xStreamBufferSendFromISR( StreamBufferHandle_t xStreamBuffer,
+ const void * pvTxData,
+ size_t xDataLengthBytes,
+ BaseType_t * const pxHigherPriorityTaskWoken )
+{
+ StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ size_t xReturn, xSpace;
+ size_t xRequiredSpace = xDataLengthBytes;
+
+ configASSERT( pvTxData );
+ configASSERT( pxStreamBuffer );
+
+ /* This send function is used to write to both message buffers and stream
+ * buffers. If this is a message buffer then the space needed must be
+ * increased by the amount of bytes needed to store the length of the
+ * message. */
+ if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
+ {
+ xRequiredSpace += sbBYTES_TO_STORE_MESSAGE_LENGTH;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ xSpace = xStreamBufferSpacesAvailable( pxStreamBuffer );
+ xReturn = prvWriteMessageToBuffer( pxStreamBuffer, pvTxData, xDataLengthBytes, xSpace, xRequiredSpace );
+
+ if( xReturn > ( size_t ) 0 )
+ {
+ /* Was a task waiting for the data? */
+ if( prvBytesInBuffer( pxStreamBuffer ) >= pxStreamBuffer->xTriggerLevelBytes )
+ {
+ sbSEND_COMPLETE_FROM_ISR( pxStreamBuffer, pxHigherPriorityTaskWoken );
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ traceSTREAM_BUFFER_SEND_FROM_ISR( xStreamBuffer, xReturn );
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+static size_t prvWriteMessageToBuffer( StreamBuffer_t * const pxStreamBuffer,
+ const void * pvTxData,
+ size_t xDataLengthBytes,
+ size_t xSpace,
+ size_t xRequiredSpace )
+{
+ size_t xNextHead = pxStreamBuffer->xHead;
+
+ if( xDataLengthBytes != xRequiredSpace )
+ {
+ /* This is a message buffer, as opposed to a stream buffer. */
+
+ if( xSpace >= xRequiredSpace )
+ {
+ /* There is enough space to write both the message length and the message
+ * itself into the buffer. Start by writing the length of the data, the data
+ * itself will be written later in this function. */
+ xNextHead = prvWriteBytesToBuffer( pxStreamBuffer, ( const uint8_t * ) &( xDataLengthBytes ), sbBYTES_TO_STORE_MESSAGE_LENGTH, xNextHead);
+ }
+ else
+ {
+ /* Not enough space, so do not write data to the buffer. */
+ xDataLengthBytes = 0;
+ }
+ }
+ else
+ {
+ /* This is a stream buffer, as opposed to a message buffer, so writing a
+ * stream of bytes rather than discrete messages. Plan to write as many
+ * bytes as possible. */
+ xDataLengthBytes = configMIN( xDataLengthBytes, xSpace );
+ }
+
+ if( xDataLengthBytes != ( size_t ) 0 )
+ {
+ /* Write the data to the buffer. */
+ pxStreamBuffer->xHead = prvWriteBytesToBuffer( pxStreamBuffer, ( const uint8_t * ) pvTxData, xDataLengthBytes, xNextHead ); /*lint !e9079 Storage buffer is implemented as uint8_t for ease of sizing, alignment and access. */
+ }
+
+ return xDataLengthBytes;
+}
+/*-----------------------------------------------------------*/
+
+size_t xStreamBufferReceive( StreamBufferHandle_t xStreamBuffer,
+ void * pvRxData,
+ size_t xBufferLengthBytes,
+ TickType_t xTicksToWait )
+{
+ StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ size_t xReceivedLength = 0, xBytesAvailable, xBytesToStoreMessageLength;
+
+ configASSERT( pvRxData );
+ configASSERT( pxStreamBuffer );
+
+ /* This receive function is used by both message buffers, which store
+ * discrete messages, and stream buffers, which store a continuous stream of
+ * bytes. Discrete messages include an additional
+ * sbBYTES_TO_STORE_MESSAGE_LENGTH bytes that hold the length of the
+ * message. */
+ if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
+ {
+ xBytesToStoreMessageLength = sbBYTES_TO_STORE_MESSAGE_LENGTH;
+ }
+ else
+ {
+ xBytesToStoreMessageLength = 0;
+ }
+
+ if( xTicksToWait != ( TickType_t ) 0 )
+ {
+ /* Checking if there is data and clearing the notification state must be
+ * performed atomically. */
+ taskENTER_CRITICAL();
+ {
+ xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
+
+ /* If this function was invoked by a message buffer read then
+ * xBytesToStoreMessageLength holds the number of bytes used to hold
+ * the length of the next discrete message. If this function was
+ * invoked by a stream buffer read then xBytesToStoreMessageLength will
+ * be 0. */
+ if( xBytesAvailable <= xBytesToStoreMessageLength )
+ {
+ /* Clear notification state as going to wait for data. */
+ ( void ) xTaskNotifyStateClear( NULL );
+
+ /* Should only be one reader. */
+ configASSERT( pxStreamBuffer->xTaskWaitingToReceive == NULL );
+ pxStreamBuffer->xTaskWaitingToReceive = xTaskGetCurrentTaskHandle();
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ taskEXIT_CRITICAL();
+
+ if( xBytesAvailable <= xBytesToStoreMessageLength )
+ {
+ /* Wait for data to be available. */
+ traceBLOCKING_ON_STREAM_BUFFER_RECEIVE( xStreamBuffer );
+ ( void ) xTaskNotifyWait( ( uint32_t ) 0, ( uint32_t ) 0, NULL, xTicksToWait );
+ pxStreamBuffer->xTaskWaitingToReceive = NULL;
+
+ /* Recheck the data available after blocking. */
+ xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
+ }
+
+ /* Whether receiving a discrete message (where xBytesToStoreMessageLength
+ * holds the number of bytes used to store the message length) or a stream of
+ * bytes (where xBytesToStoreMessageLength is zero), the number of bytes
+ * available must be greater than xBytesToStoreMessageLength to be able to
+ * read bytes from the buffer. */
+ if( xBytesAvailable > xBytesToStoreMessageLength )
+ {
+ xReceivedLength = prvReadMessageFromBuffer( pxStreamBuffer, pvRxData, xBufferLengthBytes, xBytesAvailable );
+
+ /* Was a task waiting for space in the buffer? */
+ if( xReceivedLength != ( size_t ) 0 )
+ {
+ traceSTREAM_BUFFER_RECEIVE( xStreamBuffer, xReceivedLength );
+ sbRECEIVE_COMPLETED( pxStreamBuffer );
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ traceSTREAM_BUFFER_RECEIVE_FAILED( xStreamBuffer );
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ return xReceivedLength;
+}
+/*-----------------------------------------------------------*/
+
+size_t xStreamBufferNextMessageLengthBytes( StreamBufferHandle_t xStreamBuffer )
+{
+ StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ size_t xReturn, xBytesAvailable;
+ configMESSAGE_BUFFER_LENGTH_TYPE xTempReturn;
+
+ configASSERT( pxStreamBuffer );
+
+ /* Ensure the stream buffer is being used as a message buffer. */
+ if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
+ {
+ xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
+
+ if( xBytesAvailable > sbBYTES_TO_STORE_MESSAGE_LENGTH )
+ {
+ /* The number of bytes available is greater than the number of bytes
+ * required to hold the length of the next message, so another message
+ * is available. */
+ ( void ) prvReadBytesFromBuffer( pxStreamBuffer, ( uint8_t * ) &xTempReturn, sbBYTES_TO_STORE_MESSAGE_LENGTH, pxStreamBuffer->xTail);
+ xReturn = ( size_t ) xTempReturn;
+ }
+ else
+ {
+ /* The minimum amount of bytes in a message buffer is
+ * ( sbBYTES_TO_STORE_MESSAGE_LENGTH + 1 ), so if xBytesAvailable is
+ * less than sbBYTES_TO_STORE_MESSAGE_LENGTH the only other valid
+ * value is 0. */
+ configASSERT( xBytesAvailable == 0 );
+ xReturn = 0;
+ }
+ }
+ else
+ {
+ xReturn = 0;
+ }
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+size_t xStreamBufferReceiveFromISR( StreamBufferHandle_t xStreamBuffer,
+ void * pvRxData,
+ size_t xBufferLengthBytes,
+ BaseType_t * const pxHigherPriorityTaskWoken )
+{
+ StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ size_t xReceivedLength = 0, xBytesAvailable, xBytesToStoreMessageLength;
+
+ configASSERT( pvRxData );
+ configASSERT( pxStreamBuffer );
+
+ /* This receive function is used by both message buffers, which store
+ * discrete messages, and stream buffers, which store a continuous stream of
+ * bytes. Discrete messages include an additional
+ * sbBYTES_TO_STORE_MESSAGE_LENGTH bytes that hold the length of the
+ * message. */
+ if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
+ {
+ xBytesToStoreMessageLength = sbBYTES_TO_STORE_MESSAGE_LENGTH;
+ }
+ else
+ {
+ xBytesToStoreMessageLength = 0;
+ }
+
+ xBytesAvailable = prvBytesInBuffer( pxStreamBuffer );
+
+ /* Whether receiving a discrete message (where xBytesToStoreMessageLength
+ * holds the number of bytes used to store the message length) or a stream of
+ * bytes (where xBytesToStoreMessageLength is zero), the number of bytes
+ * available must be greater than xBytesToStoreMessageLength to be able to
+ * read bytes from the buffer. */
+ if( xBytesAvailable > xBytesToStoreMessageLength )
+ {
+ xReceivedLength = prvReadMessageFromBuffer( pxStreamBuffer, pvRxData, xBufferLengthBytes, xBytesAvailable);
+
+ /* Was a task waiting for space in the buffer? */
+ if( xReceivedLength != ( size_t ) 0 )
+ {
+ sbRECEIVE_COMPLETED_FROM_ISR( pxStreamBuffer, pxHigherPriorityTaskWoken );
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ traceSTREAM_BUFFER_RECEIVE_FROM_ISR( xStreamBuffer, xReceivedLength );
+
+ return xReceivedLength;
+}
+/*-----------------------------------------------------------*/
+
+static size_t prvReadMessageFromBuffer( StreamBuffer_t * pxStreamBuffer,
+ void * pvRxData,
+ size_t xBufferLengthBytes,
+ size_t xBytesAvailable )
+{
+ size_t xCount, xNextMessageLength;
+ configMESSAGE_BUFFER_LENGTH_TYPE xTempNextMessageLength;
+ size_t xNextTail = pxStreamBuffer->xTail;
+
+ if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
+ {
+ /* A discrete message is being received. First receive the length
+ * of the message. */
+ xNextTail = prvReadBytesFromBuffer( pxStreamBuffer, ( uint8_t * ) &xTempNextMessageLength, sbBYTES_TO_STORE_MESSAGE_LENGTH, xNextTail );
+ xNextMessageLength = ( size_t ) xTempNextMessageLength;
+
+ /* Reduce the number of bytes available by the number of bytes just
+ * read out. */
+ xBytesAvailable -= sbBYTES_TO_STORE_MESSAGE_LENGTH;
+
+ /* Check there is enough space in the buffer provided by the
+ * user. */
+ if( xNextMessageLength > xBufferLengthBytes )
+ {
+ /* The user has provided insufficient space to read the message. */
+ xNextMessageLength = 0;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+ }
+ else
+ {
+ /* A stream of bytes is being received (as opposed to a discrete
+ * message), so read as many bytes as possible. */
+ xNextMessageLength = xBufferLengthBytes;
+ }
+
+ /* Use the minimum of the wanted bytes and the available bytes. */
+ xCount = configMIN( xNextMessageLength, xBytesAvailable );
+
+ if( xCount != ( size_t ) 0 )
+ {
+ /* Read the actual data and update the tail to mark the data as officially consumed. */
+ pxStreamBuffer->xTail = prvReadBytesFromBuffer( pxStreamBuffer, ( uint8_t * ) pvRxData, xCount, xNextTail); /*lint !e9079 Data storage area is implemented as uint8_t array for ease of sizing, indexing and alignment. */
+ }
+
+ return xCount;
+}
+/*-----------------------------------------------------------*/
+
+BaseType_t xStreamBufferIsEmpty( StreamBufferHandle_t xStreamBuffer )
+{
+ const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ BaseType_t xReturn;
+ size_t xTail;
+
+ configASSERT( pxStreamBuffer );
+
+ /* True if no bytes are available. */
+ xTail = pxStreamBuffer->xTail;
+
+ if( pxStreamBuffer->xHead == xTail )
+ {
+ xReturn = pdTRUE;
+ }
+ else
+ {
+ xReturn = pdFALSE;
+ }
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+BaseType_t xStreamBufferIsFull( StreamBufferHandle_t xStreamBuffer )
+{
+ BaseType_t xReturn;
+ size_t xBytesToStoreMessageLength;
+ const StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+
+ configASSERT( pxStreamBuffer );
+
+ /* This generic version of the receive function is used by both message
+ * buffers, which store discrete messages, and stream buffers, which store a
+ * continuous stream of bytes. Discrete messages include an additional
+ * sbBYTES_TO_STORE_MESSAGE_LENGTH bytes that hold the length of the message. */
+ if( ( pxStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER ) != ( uint8_t ) 0 )
+ {
+ xBytesToStoreMessageLength = sbBYTES_TO_STORE_MESSAGE_LENGTH;
+ }
+ else
+ {
+ xBytesToStoreMessageLength = 0;
+ }
+
+ /* True if the available space equals zero. */
+ if( xStreamBufferSpacesAvailable( xStreamBuffer ) <= xBytesToStoreMessageLength )
+ {
+ xReturn = pdTRUE;
+ }
+ else
+ {
+ xReturn = pdFALSE;
+ }
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+BaseType_t xStreamBufferSendCompletedFromISR( StreamBufferHandle_t xStreamBuffer,
+ BaseType_t * pxHigherPriorityTaskWoken )
+{
+ StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ BaseType_t xReturn;
+ UBaseType_t uxSavedInterruptStatus;
+
+ configASSERT( pxStreamBuffer );
+
+ uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR();
+ {
+ if( ( pxStreamBuffer )->xTaskWaitingToReceive != NULL )
+ {
+ ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToReceive,
+ ( uint32_t ) 0,
+ eNoAction,
+ pxHigherPriorityTaskWoken );
+ ( pxStreamBuffer )->xTaskWaitingToReceive = NULL;
+ xReturn = pdTRUE;
+ }
+ else
+ {
+ xReturn = pdFALSE;
+ }
+ }
+ portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+BaseType_t xStreamBufferReceiveCompletedFromISR( StreamBufferHandle_t xStreamBuffer,
+ BaseType_t * pxHigherPriorityTaskWoken )
+{
+ StreamBuffer_t * const pxStreamBuffer = xStreamBuffer;
+ BaseType_t xReturn;
+ UBaseType_t uxSavedInterruptStatus;
+
+ configASSERT( pxStreamBuffer );
+
+ uxSavedInterruptStatus = ( UBaseType_t ) portSET_INTERRUPT_MASK_FROM_ISR();
+ {
+ if( ( pxStreamBuffer )->xTaskWaitingToSend != NULL )
+ {
+ ( void ) xTaskNotifyFromISR( ( pxStreamBuffer )->xTaskWaitingToSend,
+ ( uint32_t ) 0,
+ eNoAction,
+ pxHigherPriorityTaskWoken );
+ ( pxStreamBuffer )->xTaskWaitingToSend = NULL;
+ xReturn = pdTRUE;
+ }
+ else
+ {
+ xReturn = pdFALSE;
+ }
+ }
+ portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
+
+ return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+static size_t prvWriteBytesToBuffer( StreamBuffer_t * const pxStreamBuffer,
+ const uint8_t * pucData,
+ size_t xCount,
+ size_t xHead )
+{
+ size_t xFirstLength;
+
+ configASSERT( xCount > ( size_t ) 0 );
+
+ /* Calculate the number of bytes that can be added in the first write -
+ * which may be less than the total number of bytes that need to be added if
+ * the buffer will wrap back to the beginning. */
+ xFirstLength = configMIN( pxStreamBuffer->xLength - xHead, xCount );
+
+ /* Write as many bytes as can be written in the first write. */
+ configASSERT( ( xHead + xFirstLength ) <= pxStreamBuffer->xLength );
+ ( void ) memcpy( ( void * ) ( &( pxStreamBuffer->pucBuffer[ xHead ] ) ), ( const void * ) pucData, xFirstLength ); /*lint !e9087 memcpy() requires void *. */
+
+ /* If the number of bytes written was less than the number that could be
+ * written in the first write... */
+ if( xCount > xFirstLength )
+ {
+ /* ...then write the remaining bytes to the start of the buffer. */
+ configASSERT( ( xCount - xFirstLength ) <= pxStreamBuffer->xLength );
+ ( void ) memcpy( ( void * ) pxStreamBuffer->pucBuffer, ( const void * ) &( pucData[ xFirstLength ] ), xCount - xFirstLength ); /*lint !e9087 memcpy() requires void *. */
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ xHead += xCount;
+
+ if( xHead >= pxStreamBuffer->xLength )
+ {
+ xHead -= pxStreamBuffer->xLength;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ return xHead;
+}
+/*-----------------------------------------------------------*/
+
+static size_t prvReadBytesFromBuffer( StreamBuffer_t * pxStreamBuffer,
+ uint8_t * pucData,
+ size_t xCount,
+ size_t xTail )
+{
+ size_t xFirstLength;
+
+ configASSERT( xCount != ( size_t ) 0 );
+
+ /* Calculate the number of bytes that can be read - which may be
+ * less than the number wanted if the data wraps around to the start of
+ * the buffer. */
+ xFirstLength = configMIN( pxStreamBuffer->xLength - xTail, xCount );
+
+ /* Obtain the number of bytes it is possible to obtain in the first
+ * read. Asserts check bounds of read and write. */
+ configASSERT( xFirstLength <= xCount );
+ configASSERT( ( xTail + xFirstLength ) <= pxStreamBuffer->xLength );
+ ( void ) memcpy( ( void * ) pucData, ( const void * ) &( pxStreamBuffer->pucBuffer[ xTail ] ), xFirstLength ); /*lint !e9087 memcpy() requires void *. */
+
+ /* If the total number of wanted bytes is greater than the number
+ * that could be read in the first read... */
+ if( xCount > xFirstLength )
+ {
+ /* ...then read the remaining bytes from the start of the buffer. */
+ configASSERT( xCount <= xCount );
+ ( void ) memcpy( ( void * ) &( pucData[ xFirstLength ] ), ( void * ) ( pxStreamBuffer->pucBuffer ), xCount - xFirstLength ); /*lint !e9087 memcpy() requires void *. */
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ /* Move the tail pointer to effectively remove the data read from the buffer. */
+ xTail += xCount;
+
+ if( xTail >= pxStreamBuffer->xLength )
+ {
+ xTail -= pxStreamBuffer->xLength;
+ }
+
+ return xTail;
+}
+/*-----------------------------------------------------------*/
+
+static size_t prvBytesInBuffer( const StreamBuffer_t * const pxStreamBuffer )
+{
+/* Returns the distance between xTail and xHead. */
+ size_t xCount;
+
+ xCount = pxStreamBuffer->xLength + pxStreamBuffer->xHead;
+ xCount -= pxStreamBuffer->xTail;
+
+ if( xCount >= pxStreamBuffer->xLength )
+ {
+ xCount -= pxStreamBuffer->xLength;
+ }
+ else
+ {
+ mtCOVERAGE_TEST_MARKER();
+ }
+
+ return xCount;
+}
+/*-----------------------------------------------------------*/
+
+static void prvInitialiseNewStreamBuffer( StreamBuffer_t * const pxStreamBuffer,
+ uint8_t * const pucBuffer,
+ size_t xBufferSizeBytes,
+ size_t xTriggerLevelBytes,
+ uint8_t ucFlags )
+{
+ /* Assert here is deliberately writing to the entire buffer to ensure it can
+ * be written to without generating exceptions, and is setting the buffer to a
+ * known value to assist in development/debugging. */
+ #if ( configASSERT_DEFINED == 1 )
+ {
+ /* The value written just has to be identifiable when looking at the
+ * memory. Don't use 0xA5 as that is the stack fill value and could
+ * result in confusion as to what is actually being observed. */
+ const BaseType_t xWriteValue = 0x55;
+ configASSERT( memset( pucBuffer, ( int ) xWriteValue, xBufferSizeBytes ) == pucBuffer );
+ } /*lint !e529 !e438 xWriteValue is only used if configASSERT() is defined. */
+ #endif
+
+ ( void ) memset( ( void * ) pxStreamBuffer, 0x00, sizeof( StreamBuffer_t ) ); /*lint !e9087 memset() requires void *. */
+ pxStreamBuffer->pucBuffer = pucBuffer;
+ pxStreamBuffer->xLength = xBufferSizeBytes;
+ pxStreamBuffer->xTriggerLevelBytes = xTriggerLevelBytes;
+ pxStreamBuffer->ucFlags = ucFlags;
+}
+
+#if ( configUSE_TRACE_FACILITY == 1 )
+
+ UBaseType_t uxStreamBufferGetStreamBufferNumber( StreamBufferHandle_t xStreamBuffer )
+ {
+ return xStreamBuffer->uxStreamBufferNumber;
+ }
+
+#endif /* configUSE_TRACE_FACILITY */
+/*-----------------------------------------------------------*/
+
+#if ( configUSE_TRACE_FACILITY == 1 )
+
+ void vStreamBufferSetStreamBufferNumber( StreamBufferHandle_t xStreamBuffer,
+ UBaseType_t uxStreamBufferNumber )
+ {
+ xStreamBuffer->uxStreamBufferNumber = uxStreamBufferNumber;
+ }
+
+#endif /* configUSE_TRACE_FACILITY */
+/*-----------------------------------------------------------*/
+
+#if ( configUSE_TRACE_FACILITY == 1 )
+
+ uint8_t ucStreamBufferGetStreamBufferType( StreamBufferHandle_t xStreamBuffer )
+ {
+ return( xStreamBuffer->ucFlags & sbFLAGS_IS_MESSAGE_BUFFER );
+ }
+
+#endif /* configUSE_TRACE_FACILITY */
+/*-----------------------------------------------------------*/
