diff options
| author | hathach <[email protected]> | 2020-03-10 14:49:01 +0700 |
|---|---|---|
| committer | hathach <[email protected]> | 2020-03-10 14:49:01 +0700 |
| commit | 39ce2e8361730e50fef7c968195d759de1800bcd (patch) | |
| tree | 8f6bacb03056b417b772f77ee9d2181477ef6655 /lib/FreeRTOS/Source/include/stream_buffer.h | |
| parent | 1561692e4aa0e66484c541ab4977393bd58dba86 (diff) | |
adding FreeRTOS as submodule
Diffstat (limited to 'lib/FreeRTOS/Source/include/stream_buffer.h')
| -rw-r--r-- | lib/FreeRTOS/Source/include/stream_buffer.h | 852 |
1 files changed, 0 insertions, 852 deletions
diff --git a/lib/FreeRTOS/Source/include/stream_buffer.h b/lib/FreeRTOS/Source/include/stream_buffer.h deleted file mode 100644 index 5418e05ba..000000000 --- a/lib/FreeRTOS/Source/include/stream_buffer.h +++ /dev/null @@ -1,852 +0,0 @@ -/* - * FreeRTOS Kernel V10.0.1 - * Copyright (C) 2017 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. - * - * http://www.FreeRTOS.org - * http://aws.amazon.com/freertos - * - * 1 tab == 4 spaces! - */ - -/* - * Stream buffers are used to send a continuous stream of data from one task or - * interrupt to another. Their implementation is light weight, making them - * particularly suited for interrupt to task and core to core communication - * scenarios. - * - * ***NOTE***: Uniquely among FreeRTOS objects, the stream buffer - * implementation (so also the message buffer implementation, as message buffers - * are built on top of stream buffers) assumes there is only one task or - * interrupt that will write to the buffer (the writer), and only one task or - * interrupt that will read from the buffer (the reader). It is safe for the - * writer and reader to be different tasks or interrupts, but, unlike other - * FreeRTOS objects, it is not safe to have multiple different writers or - * multiple different readers. If there are to be multiple different writers - * then the application writer must place each call to a writing API function - * (such as xStreamBufferSend()) inside a critical section and set the send - * block time to 0. Likewise, if there are to be multiple different readers - * then the application writer must place each call to a reading API function - * (such as xStreamBufferRead()) inside a critical section section and set the - * receive block time to 0. - * - */ - -#ifndef STREAM_BUFFER_H -#define STREAM_BUFFER_H - -#if defined( __cplusplus ) -extern "C" { -#endif - -/** - * Type by which stream buffers are referenced. For example, a call to - * xStreamBufferCreate() returns an StreamBufferHandle_t variable that can - * then be used as a parameter to xStreamBufferSend(), xStreamBufferReceive(), - * etc. - */ -typedef void * StreamBufferHandle_t; - - -/** - * message_buffer.h - * -<pre> -StreamBufferHandle_t xStreamBufferCreate( size_t xBufferSizeBytes, size_t xTriggerLevelBytes ); -</pre> - * - * Creates a new stream buffer using dynamically allocated memory. See - * xStreamBufferCreateStatic() for a version that uses statically allocated - * memory (memory that is allocated at compile time). - * - * configSUPPORT_DYNAMIC_ALLOCATION must be set to 1 or left undefined in - * FreeRTOSConfig.h for xStreamBufferCreate() to be available. - * - * @param xBufferSizeBytes The total number of bytes the stream buffer will be - * able to hold at any one time. - * - * @param xTriggerLevelBytes 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. - * - * @return If NULL is returned, then the stream buffer cannot be created - * because there is insufficient heap memory available for FreeRTOS to allocate - * the stream buffer data structures and storage area. A non-NULL value being - * returned indicates that the stream buffer has been created successfully - - * the returned value should be stored as the handle to the created stream - * buffer. - * - * Example use: -<pre> - -void vAFunction( void ) -{ -StreamBufferHandle_t xStreamBuffer; -const size_t xStreamBufferSizeBytes = 100, xTriggerLevel = 10; - - // Create a stream buffer that can hold 100 bytes. The memory used to hold - // both the stream buffer structure and the data in the stream buffer is - // allocated dynamically. - xStreamBuffer = xStreamBufferCreate( xStreamBufferSizeBytes, xTriggerLevel ); - - if( xStreamBuffer == NULL ) - { - // There was not enough heap memory space available to create the - // stream buffer. - } - else - { - // The stream buffer was created successfully and can now be used. - } -} -</pre> - * \defgroup xStreamBufferCreate xStreamBufferCreate - * \ingroup StreamBufferManagement - */ -#define xStreamBufferCreate( xBufferSizeBytes, xTriggerLevelBytes ) xStreamBufferGenericCreate( xBufferSizeBytes, xTriggerLevelBytes, pdFALSE ) - -/** - * stream_buffer.h - * -<pre> -StreamBufferHandle_t xStreamBufferCreateStatic( size_t xBufferSizeBytes, - size_t xTriggerLevelBytes, - uint8_t *pucStreamBufferStorageArea, - StaticStreamBuffer_t *pxStaticStreamBuffer ); -</pre> - * Creates a new stream buffer using statically allocated memory. See - * xStreamBufferCreate() for a version that uses dynamically allocated memory. - * - * configSUPPORT_STATIC_ALLOCATION must be set to 1 in FreeRTOSConfig.h for - * xStreamBufferCreateStatic() to be available. - * - * @param xBufferSizeBytes The size, in bytes, of the buffer pointed to by the - * pucStreamBufferStorageArea parameter. - * - * @param xTriggerLevelBytes 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. - * - * @param pucStreamBufferStorageArea Must point to a uint8_t array that is at - * least xBufferSizeBytes + 1 big. This is the array to which streams are - * copied when they are written to the stream buffer. - * - * @param pxStaticStreamBuffer Must point to a variable of type - * StaticStreamBuffer_t, which will be used to hold the stream buffer's data - * structure. - * - * @return If the stream buffer is created successfully then a handle to the - * created stream buffer is returned. If either pucStreamBufferStorageArea or - * pxStaticstreamBuffer are NULL then NULL is returned. - * - * Example use: -<pre> - -// Used to dimension the array used to hold the streams. The available space -// will actually be one less than this, so 999. -#define STORAGE_SIZE_BYTES 1000 - -// Defines the memory that will actually hold the streams within the stream -// buffer. -static uint8_t ucStorageBuffer[ STORAGE_SIZE_BYTES ]; - -// The variable used to hold the stream buffer structure. -StaticStreamBuffer_t xStreamBufferStruct; - -void MyFunction( void ) -{ -StreamBufferHandle_t xStreamBuffer; -const size_t xTriggerLevel = 1; - - xStreamBuffer = xStreamBufferCreateStatic( sizeof( ucBufferStorage ), - xTriggerLevel, - ucBufferStorage, - &xStreamBufferStruct ); - - // As neither the pucStreamBufferStorageArea or pxStaticStreamBuffer - // parameters were NULL, xStreamBuffer will not be NULL, and can be used to - // reference the created stream buffer in other stream buffer API calls. - - // Other code that uses the stream buffer can go here. -} - -</pre> - * \defgroup xStreamBufferCreateStatic xStreamBufferCreateStatic - * \ingroup StreamBufferManagement - */ -#define xStreamBufferCreateStatic( xBufferSizeBytes, xTriggerLevelBytes, pucStreamBufferStorageArea, pxStaticStreamBuffer ) xStreamBufferGenericCreateStatic( xBufferSizeBytes, xTriggerLevelBytes, pdFALSE, pucStreamBufferStorageArea, pxStaticStreamBuffer ) - -/** - * stream_buffer.h - * -<pre> -size_t xStreamBufferSend( StreamBufferHandle_t xStreamBuffer, - const void *pvTxData, - size_t xDataLengthBytes, - TickType_t xTicksToWait ); -<pre> - * - * Sends bytes to a stream buffer. The bytes are copied into the stream buffer. - * - * ***NOTE***: Uniquely among FreeRTOS objects, the stream buffer - * implementation (so also the message buffer implementation, as message buffers - * are built on top of stream buffers) assumes there is only one task or - * interrupt that will write to the buffer (the writer), and only one task or - * interrupt that will read from the buffer (the reader). It is safe for the - * writer and reader to be different tasks or interrupts, but, unlike other - * FreeRTOS objects, it is not safe to have multiple different writers or - * multiple different readers. If there are to be multiple different writers - * then the application writer must place each call to a writing API function - * (such as xStreamBufferSend()) inside a critical section and set the send - * block time to 0. Likewise, if there are to be multiple different readers - * then the application writer must place each call to a reading API function - * (such as xStreamBufferRead()) inside a critical section and set the receive - * block time to 0. - * - * Use xStreamBufferSend() to write to a stream buffer from a task. Use - * xStreamBufferSendFromISR() to write to a stream buffer from an interrupt - * service routine (ISR). - * - * @param xStreamBuffer The handle of the stream buffer to which a stream is - * being sent. - * - * @param pvTxData A pointer to the buffer that holds the bytes to be copied - * into the stream buffer. - * - * @param xDataLengthBytes The maximum number of bytes to copy from pvTxData - * into the stream buffer. - * - * @param xTicksToWait The maximum amount of time the task should remain in the - * Blocked state to wait for enough space to become available in the stream - * buffer, should the stream buffer contain too little space to hold the - * another xDataLengthBytes bytes. The block time is specified in tick periods, - * so the absolute time it represents is dependent on the tick frequency. The - * macro pdMS_TO_TICKS() can be used to convert a time specified in milliseconds - * into a time specified in ticks. Setting xTicksToWait to portMAX_DELAY will - * cause the task to wait indefinitely (without timing out), provided - * INCLUDE_vTaskSuspend is set to 1 in FreeRTOSConfig.h. If a task times out - * before it can write all xDataLengthBytes into the buffer it will still write - * as many bytes as possible. A task does not use any CPU time when it is in - * the blocked state. - * - * @return The number of bytes written to the stream buffer. If a task times - * out before it can write all xDataLengthBytes into the buffer it will still - * write as many bytes as possible. - * - * Example use: -<pre> -void vAFunction( StreamBufferHandle_t xStreamBuffer ) -{ -size_t xBytesSent; -uint8_t ucArrayToSend[] = { 0, 1, 2, 3 }; -char *pcStringToSend = "String to send"; -const TickType_t x100ms = pdMS_TO_TICKS( 100 ); - - // Send an array to the stream buffer, blocking for a maximum of 100ms to - // wait for enough space to be available in the stream buffer. - xBytesSent = xStreamBufferSend( xStreamBuffer, ( void * ) ucArrayToSend, sizeof( ucArrayToSend ), x100ms ); - - if( xBytesSent != sizeof( ucArrayToSend ) ) - { - // The call to xStreamBufferSend() times out before there was enough - // space in the buffer for the data to be written, but it did - // successfully write xBytesSent bytes. - } - - // Send the string to the stream buffer. Return immediately if there is not - // enough space in the buffer. - xBytesSent = xStreamBufferSend( xStreamBuffer, ( void * ) pcStringToSend, strlen( pcStringToSend ), 0 ); - - if( xBytesSent != strlen( pcStringToSend ) ) - { - // The entire string could not be added to the stream buffer because - // there was not enough free space in the buffer, but xBytesSent bytes - // were sent. Could try again to send the remaining bytes. - } -} -</pre> - * \defgroup xStreamBufferSend xStreamBufferSend - * \ingroup StreamBufferManagement - */ -size_t xStreamBufferSend( StreamBufferHandle_t xStreamBuffer, - const void *pvTxData, - size_t xDataLengthBytes, - TickType_t xTicksToWait ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -size_t xStreamBufferSendFromISR( StreamBufferHandle_t xStreamBuffer, - const void *pvTxData, - size_t xDataLengthBytes, - BaseType_t *pxHigherPriorityTaskWoken ); -<pre> - * - * Interrupt safe version of the API function that sends a stream of bytes to - * the stream buffer. - * - * ***NOTE***: Uniquely among FreeRTOS objects, the stream buffer - * implementation (so also the message buffer implementation, as message buffers - * are built on top of stream buffers) assumes there is only one task or - * interrupt that will write to the buffer (the writer), and only one task or - * interrupt that will read from the buffer (the reader). It is safe for the - * writer and reader to be different tasks or interrupts, but, unlike other - * FreeRTOS objects, it is not safe to have multiple different writers or - * multiple different readers. If there are to be multiple different writers - * then the application writer must place each call to a writing API function - * (such as xStreamBufferSend()) inside a critical section and set the send - * block time to 0. Likewise, if there are to be multiple different readers - * then the application writer must place each call to a reading API function - * (such as xStreamBufferRead()) inside a critical section and set the receive - * block time to 0. - * - * Use xStreamBufferSend() to write to a stream buffer from a task. Use - * xStreamBufferSendFromISR() to write to a stream buffer from an interrupt - * service routine (ISR). - * - * @param xStreamBuffer The handle of the stream buffer to which a stream is - * being sent. - * - * @param pvTxData A pointer to the data that is to be copied into the stream - * buffer. - * - * @param xDataLengthBytes The maximum number of bytes to copy from pvTxData - * into the stream buffer. - * - * @param pxHigherPriorityTaskWoken It is possible that a stream buffer will - * have a task blocked on it waiting for data. Calling - * xStreamBufferSendFromISR() can make data available, and so cause a task that - * was waiting for data to leave the Blocked state. If calling - * xStreamBufferSendFromISR() causes a task to leave the Blocked state, and the - * unblocked task has a priority higher than the currently executing task (the - * task that was interrupted), then, internally, xStreamBufferSendFromISR() - * will set *pxHigherPriorityTaskWoken to pdTRUE. If - * xStreamBufferSendFromISR() sets this value to pdTRUE, then normally a - * context switch should be performed before the interrupt is exited. This will - * ensure that the interrupt returns directly to the highest priority Ready - * state task. *pxHigherPriorityTaskWoken should be set to pdFALSE before it - * is passed into the function. See the example code below for an example. - * - * @return The number of bytes actually written to the stream buffer, which will - * be less than xDataLengthBytes if the stream buffer didn't have enough free - * space for all the bytes to be written. - * - * Example use: -<pre> -// A stream buffer that has already been created. -StreamBufferHandle_t xStreamBuffer; - -void vAnInterruptServiceRoutine( void ) -{ -size_t xBytesSent; -char *pcStringToSend = "String to send"; -BaseType_t xHigherPriorityTaskWoken = pdFALSE; // Initialised to pdFALSE. - - // Attempt to send the string to the stream buffer. - xBytesSent = xStreamBufferSendFromISR( xStreamBuffer, - ( void * ) pcStringToSend, - strlen( pcStringToSend ), - &xHigherPriorityTaskWoken ); - - if( xBytesSent != strlen( pcStringToSend ) ) - { - // There was not enough free space in the stream buffer for the entire - // string to be written, ut xBytesSent bytes were written. - } - - // If xHigherPriorityTaskWoken was set to pdTRUE inside - // xStreamBufferSendFromISR() then a task that has a priority above the - // priority of the currently executing task was unblocked and a context - // switch should be performed to ensure the ISR returns to the unblocked - // task. In most FreeRTOS ports this is done by simply passing - // xHigherPriorityTaskWoken into taskYIELD_FROM_ISR(), which will test the - // variables value, and perform the context switch if necessary. Check the - // documentation for the port in use for port specific instructions. - taskYIELD_FROM_ISR( xHigherPriorityTaskWoken ); -} -</pre> - * \defgroup xStreamBufferSendFromISR xStreamBufferSendFromISR - * \ingroup StreamBufferManagement - */ -size_t xStreamBufferSendFromISR( StreamBufferHandle_t xStreamBuffer, - const void *pvTxData, - size_t xDataLengthBytes, - BaseType_t * const pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -size_t xStreamBufferReceive( StreamBufferHandle_t xStreamBuffer, - void *pvRxData, - size_t xBufferLengthBytes, - TickType_t xTicksToWait ); -</pre> - * - * Receives bytes from a stream buffer. - * - * ***NOTE***: Uniquely among FreeRTOS objects, the stream buffer - * implementation (so also the message buffer implementation, as message buffers - * are built on top of stream buffers) assumes there is only one task or - * interrupt that will write to the buffer (the writer), and only one task or - * interrupt that will read from the buffer (the reader). It is safe for the - * writer and reader to be different tasks or interrupts, but, unlike other - * FreeRTOS objects, it is not safe to have multiple different writers or - * multiple different readers. If there are to be multiple different writers - * then the application writer must place each call to a writing API function - * (such as xStreamBufferSend()) inside a critical section and set the send - * block time to 0. Likewise, if there are to be multiple different readers - * then the application writer must place each call to a reading API function - * (such as xStreamBufferRead()) inside a critical section and set the receive - * block time to 0. - * - * Use xStreamBufferReceive() to read from a stream buffer from a task. Use - * xStreamBufferReceiveFromISR() to read from a stream buffer from an - * interrupt service routine (ISR). - * - * @param xStreamBuffer The handle of the stream buffer from which bytes are to - * be received. - * - * @param pvRxData A pointer to the buffer into which the received bytes will be - * copied. - * - * @param xBufferLengthBytes The length of the buffer pointed to by the - * pvRxData parameter. This sets the maximum number of bytes to receive in one - * call. xStreamBufferReceive will return as many bytes as possible up to a - * maximum set by xBufferLengthBytes. - * - * @param xTicksToWait The maximum amount of time the task should remain in the - * Blocked state to wait for data to become available if the stream buffer is - * empty. xStreamBufferReceive() will return immediately if xTicksToWait is - * zero. The block time is specified in tick periods, so the absolute time it - * represents is dependent on the tick frequency. The macro pdMS_TO_TICKS() can - * be used to convert a time specified in milliseconds into a time specified in - * ticks. Setting xTicksToWait to portMAX_DELAY will cause the task to wait - * indefinitely (without timing out), provided INCLUDE_vTaskSuspend is set to 1 - * in FreeRTOSConfig.h. A task does not use any CPU time when it is in the - * Blocked state. - * - * @return The number of bytes actually read from the stream buffer, which will - * be less than xBufferLengthBytes if the call to xStreamBufferReceive() timed - * out before xBufferLengthBytes were available. - * - * Example use: -<pre> -void vAFunction( StreamBuffer_t xStreamBuffer ) -{ -uint8_t ucRxData[ 20 ]; -size_t xReceivedBytes; -const TickType_t xBlockTime = pdMS_TO_TICKS( 20 ); - - // Receive up to another sizeof( ucRxData ) bytes from the stream buffer. - // Wait in the Blocked state (so not using any CPU processing time) for a - // maximum of 100ms for the full sizeof( ucRxData ) number of bytes to be - // available. - xReceivedBytes = xStreamBufferReceive( xStreamBuffer, - ( void * ) ucRxData, - sizeof( ucRxData ), - xBlockTime ); - - if( xReceivedBytes > 0 ) - { - // A ucRxData contains another xRecievedBytes bytes of data, which can - // be processed here.... - } -} -</pre> - * \defgroup xStreamBufferReceive xStreamBufferReceive - * \ingroup StreamBufferManagement - */ -size_t xStreamBufferReceive( StreamBufferHandle_t xStreamBuffer, - void *pvRxData, - size_t xBufferLengthBytes, - TickType_t xTicksToWait ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -size_t xStreamBufferReceiveFromISR( StreamBufferHandle_t xStreamBuffer, - void *pvRxData, - size_t xBufferLengthBytes, - BaseType_t *pxHigherPriorityTaskWoken ); -</pre> - * - * An interrupt safe version of the API function that receives bytes from a - * stream buffer. - * - * Use xStreamBufferReceive() to read bytes from a stream buffer from a task. - * Use xStreamBufferReceiveFromISR() to read bytes from a stream buffer from an - * interrupt service routine (ISR). - * - * @param xStreamBuffer The handle of the stream buffer from which a stream - * is being received. - * - * @param pvRxData A pointer to the buffer into which the received bytes are - * copied. - * - * @param xBufferLengthBytes The length of the buffer pointed to by the - * pvRxData parameter. This sets the maximum number of bytes to receive in one - * call. xStreamBufferReceive will return as many bytes as possible up to a - * maximum set by xBufferLengthBytes. - * - * @param pxHigherPriorityTaskWoken It is possible that a stream buffer will - * have a task blocked on it waiting for space to become available. Calling - * xStreamBufferReceiveFromISR() can make space available, and so cause a task - * that is waiting for space to leave the Blocked state. If calling - * xStreamBufferReceiveFromISR() causes a task to leave the Blocked state, and - * the unblocked task has a priority higher than the currently executing task - * (the task that was interrupted), then, internally, - * xStreamBufferReceiveFromISR() will set *pxHigherPriorityTaskWoken to pdTRUE. - * If xStreamBufferReceiveFromISR() sets this value to pdTRUE, then normally a - * context switch should be performed before the interrupt is exited. That will - * ensure the interrupt returns directly to the highest priority Ready state - * task. *pxHigherPriorityTaskWoken should be set to pdFALSE before it is - * passed into the function. See the code example below for an example. - * - * @return The number of bytes read from the stream buffer, if any. - * - * Example use: -<pre> -// A stream buffer that has already been created. -StreamBuffer_t xStreamBuffer; - -void vAnInterruptServiceRoutine( void ) -{ -uint8_t ucRxData[ 20 ]; -size_t xReceivedBytes; -BaseType_t xHigherPriorityTaskWoken = pdFALSE; // Initialised to pdFALSE. - - // Receive the next stream from the stream buffer. - xReceivedBytes = xStreamBufferReceiveFromISR( xStreamBuffer, - ( void * ) ucRxData, - sizeof( ucRxData ), - &xHigherPriorityTaskWoken ); - - if( xReceivedBytes > 0 ) - { - // ucRxData contains xReceivedBytes read from the stream buffer. - // Process the stream here.... - } - - // If xHigherPriorityTaskWoken was set to pdTRUE inside - // xStreamBufferReceiveFromISR() then a task that has a priority above the - // priority of the currently executing task was unblocked and a context - // switch should be performed to ensure the ISR returns to the unblocked - // task. In most FreeRTOS ports this is done by simply passing - // xHigherPriorityTaskWoken into taskYIELD_FROM_ISR(), which will test the - // variables value, and perform the context switch if necessary. Check the - // documentation for the port in use for port specific instructions. - taskYIELD_FROM_ISR( xHigherPriorityTaskWoken ); -} -</pre> - * \defgroup xStreamBufferReceiveFromISR xStreamBufferReceiveFromISR - * \ingroup StreamBufferManagement - */ -size_t xStreamBufferReceiveFromISR( StreamBufferHandle_t xStreamBuffer, - void *pvRxData, - size_t xBufferLengthBytes, - BaseType_t * const pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -void vStreamBufferDelete( StreamBufferHandle_t xStreamBuffer ); -</pre> - * - * Deletes a stream buffer that was previously created using a call to - * xStreamBufferCreate() or xStreamBufferCreateStatic(). If the stream - * buffer was created using dynamic memory (that is, by xStreamBufferCreate()), - * then the allocated memory is freed. - * - * A stream buffer handle must not be used after the stream buffer has been - * deleted. - * - * @param xStreamBuffer The handle of the stream buffer to be deleted. - * - * \defgroup vStreamBufferDelete vStreamBufferDelete - * \ingroup StreamBufferManagement - */ -void vStreamBufferDelete( StreamBufferHandle_t xStreamBuffer ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -BaseType_t xStreamBufferIsFull( StreamBufferHandle_t xStreamBuffer ); -</pre> - * - * Queries a stream buffer to see if it is full. A stream buffer is full if it - * does not have any free space, and therefore cannot accept any more data. - * - * @param xStreamBuffer The handle of the stream buffer being queried. - * - * @return If the stream buffer is full then pdTRUE is returned. Otherwise - * pdFALSE is returned. - * - * \defgroup xStreamBufferIsFull xStreamBufferIsFull - * \ingroup StreamBufferManagement - */ -BaseType_t xStreamBufferIsFull( StreamBufferHandle_t xStreamBuffer ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -BaseType_t xStreamBufferIsEmpty( StreamBufferHandle_t xStreamBuffer ); -</pre> - * - * Queries a stream buffer to see if it is empty. A stream buffer is empty if - * it does not contain any data. - * - * @param xStreamBuffer The handle of the stream buffer being queried. - * - * @return If the stream buffer is empty then pdTRUE is returned. Otherwise - * pdFALSE is returned. - * - * \defgroup xStreamBufferIsEmpty xStreamBufferIsEmpty - * \ingroup StreamBufferManagement - */ -BaseType_t xStreamBufferIsEmpty( StreamBufferHandle_t xStreamBuffer ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -BaseType_t xStreamBufferReset( StreamBufferHandle_t xStreamBuffer ); -</pre> - * - * Resets a stream buffer to its initial, empty, state. Any data that was in - * the stream buffer is discarded. A stream buffer can only be reset if there - * are no tasks blocked waiting to either send to or receive from the stream - * buffer. - * - * @param xStreamBuffer The handle of the stream buffer being reset. - * - * @return If the stream buffer is reset then pdPASS is returned. If there was - * a task blocked waiting to send to or read from the stream buffer then the - * stream buffer is not reset and pdFAIL is returned. - * - * \defgroup xStreamBufferReset xStreamBufferReset - * \ingroup StreamBufferManagement - */ -BaseType_t xStreamBufferReset( StreamBufferHandle_t xStreamBuffer ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -size_t xStreamBufferSpacesAvailable( StreamBufferHandle_t xStreamBuffer ); -</pre> - * - * Queries a stream buffer to see how much free space it contains, which is - * equal to the amount of data that can be sent to the stream buffer before it - * is full. - * - * @param xStreamBuffer The handle of the stream buffer being queried. - * - * @return The number of bytes that can be written to the stream buffer before - * the stream buffer would be full. - * - * \defgroup xStreamBufferSpacesAvailable xStreamBufferSpacesAvailable - * \ingroup StreamBufferManagement - */ -size_t xStreamBufferSpacesAvailable( StreamBufferHandle_t xStreamBuffer ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -size_t xStreamBufferBytesAvailable( StreamBufferHandle_t xStreamBuffer ); -</pre> - * - * Queries a stream buffer to see how much data it contains, which is equal to - * the number of bytes that can be read from the stream buffer before the stream - * buffer would be empty. - * - * @param xStreamBuffer The handle of the stream buffer being queried. - * - * @return The number of bytes that can be read from the stream buffer before - * the stream buffer would be empty. - * - * \defgroup xStreamBufferBytesAvailable xStreamBufferBytesAvailable - * \ingroup StreamBufferManagement - */ -size_t xStreamBufferBytesAvailable( StreamBufferHandle_t xStreamBuffer ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -BaseType_t xStreamBufferSetTriggerLevel( StreamBufferHandle_t xStreamBuffer, size_t xTriggerLevel ); -</pre> - * - * A stream buffer's trigger level is 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. - * - * A trigger level is set when the stream buffer is created, and can be modified - * using xStreamBufferSetTriggerLevel(). - * - * @param xStreamBuffer The handle of the stream buffer being updated. - * - * @param xTriggerLevel The new trigger level for the stream buffer. - * - * @return If xTriggerLevel was less than or equal to the stream buffer's length - * then the trigger level will be updated and pdTRUE is returned. Otherwise - * pdFALSE is returned. - * - * \defgroup xStreamBufferSetTriggerLevel xStreamBufferSetTriggerLevel - * \ingroup StreamBufferManagement - */ -BaseType_t xStreamBufferSetTriggerLevel( StreamBufferHandle_t xStreamBuffer, size_t xTriggerLevel ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -BaseType_t xStreamBufferSendCompletedFromISR( StreamBufferHandle_t xStreamBuffer, BaseType_t *pxHigherPriorityTaskWoken ); -</pre> - * - * For advanced users only. - * - * The sbSEND_COMPLETED() macro is called from within the FreeRTOS APIs when - * data is sent to a message buffer or stream buffer. If there was a task that - * was blocked on the message or stream buffer waiting for data to arrive then - * the sbSEND_COMPLETED() macro sends a notification to the task to remove it - * from the Blocked state. xStreamBufferSendCompletedFromISR() does the same - * thing. It is provided to enable application writers to implement their own - * version of sbSEND_COMPLETED(), and MUST NOT BE USED AT ANY OTHER TIME. - * - * See the example implemented in FreeRTOS/Demo/Minimal/MessageBufferAMP.c for - * additional information. - * - * @param xStreamBuffer The handle of the stream buffer to which data was - * written. - * - * @param pxHigherPriorityTaskWoken *pxHigherPriorityTaskWoken should be - * initialised to pdFALSE before it is passed into - * xStreamBufferSendCompletedFromISR(). If calling - * xStreamBufferSendCompletedFromISR() removes a task from the Blocked state, - * and the task has a priority above the priority of the currently running task, - * then *pxHigherPriorityTaskWoken will get set to pdTRUE indicating that a - * context switch should be performed before exiting the ISR. - * - * @return If a task was removed from the Blocked state then pdTRUE is returned. - * Otherwise pdFALSE is returned. - * - * \defgroup xStreamBufferSendCompletedFromISR xStreamBufferSendCompletedFromISR - * \ingroup StreamBufferManagement - */ -BaseType_t xStreamBufferSendCompletedFromISR( StreamBufferHandle_t xStreamBuffer, BaseType_t *pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION; - -/** - * stream_buffer.h - * -<pre> -BaseType_t xStreamBufferReceiveCompletedFromISR( StreamBufferHandle_t xStreamBuffer, BaseType_t *pxHigherPriorityTaskWoken ); -</pre> - * - * For advanced users only. - * - * The sbRECEIVE_COMPLETED() macro is called from within the FreeRTOS APIs when - * data is read out of a message buffer or stream buffer. If there was a task - * that was blocked on the message or stream buffer waiting for data to arrive - * then the sbRECEIVE_COMPLETED() macro sends a notification to the task to - * remove it from the Blocked state. xStreamBufferReceiveCompletedFromISR() - * does the same thing. It is provided to enable application writers to - * implement their own version of sbRECEIVE_COMPLETED(), and MUST NOT BE USED AT - * ANY OTHER TIME. - * - * See the example implemented in FreeRTOS/Demo/Minimal/MessageBufferAMP.c for - * additional information. - * - * @param xStreamBuffer The handle of the stream buffer from which data was - * read. - * - * @param pxHigherPriorityTaskWoken *pxHigherPriorityTaskWoken should be - * initialised to pdFALSE before it is passed into - * xStreamBufferReceiveCompletedFromISR(). If calling - * xStreamBufferReceiveCompletedFromISR() removes a task from the Blocked state, - * and the task has a priority above the priority of the currently running task, - * then *pxHigherPriorityTaskWoken will get set to pdTRUE indicating that a - * context switch should be performed before exiting the ISR. - * - * @return If a task was removed from the Blocked state then pdTRUE is returned. - * Otherwise pdFALSE is returned. - * - * \defgroup xStreamBufferReceiveCompletedFromISR xStreamBufferReceiveCompletedFromISR - * \ingroup StreamBufferManagement - */ -BaseType_t xStreamBufferReceiveCompletedFromISR( StreamBufferHandle_t xStreamBuffer, BaseType_t *pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION; - -/* Functions below here are not part of the public API. */ -StreamBufferHandle_t xStreamBufferGenericCreate( size_t xBufferSizeBytes, - size_t xTriggerLevelBytes, - BaseType_t xIsMessageBuffer ) PRIVILEGED_FUNCTION; - -StreamBufferHandle_t xStreamBufferGenericCreateStatic( size_t xBufferSizeBytes, - size_t xTriggerLevelBytes, - BaseType_t xIsMessageBuffer, - uint8_t * const pucStreamBufferStorageArea, - StaticStreamBuffer_t * const pxStaticStreamBuffer ) PRIVILEGED_FUNCTION; - -#if( configUSE_TRACE_FACILITY == 1 ) - void vStreamBufferSetStreamBufferNumber( StreamBufferHandle_t xStreamBuffer, UBaseType_t uxStreamBufferNumber ) PRIVILEGED_FUNCTION; - UBaseType_t uxStreamBufferGetStreamBufferNumber( StreamBufferHandle_t xStreamBuffer ) PRIVILEGED_FUNCTION; - uint8_t ucStreamBufferGetStreamBufferType( StreamBufferHandle_t xStreamBuffer ) PRIVILEGED_FUNCTION; -#endif - -#if defined( __cplusplus ) -} -#endif - -#endif /* !defined( STREAM_BUFFER_H ) */ |
