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authorhathach <[email protected]>2020-03-10 14:49:01 +0700
committerhathach <[email protected]>2020-03-10 14:49:01 +0700
commit39ce2e8361730e50fef7c968195d759de1800bcd (patch)
tree8f6bacb03056b417b772f77ee9d2181477ef6655 /lib/FreeRTOS/Source/include/stream_buffer.h
parent1561692e4aa0e66484c541ab4977393bd58dba86 (diff)
adding FreeRTOS as submodule
Diffstat (limited to 'lib/FreeRTOS/Source/include/stream_buffer.h')
-rw-r--r--lib/FreeRTOS/Source/include/stream_buffer.h852
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diff --git a/lib/FreeRTOS/Source/include/stream_buffer.h b/lib/FreeRTOS/Source/include/stream_buffer.h
deleted file mode 100644
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--- 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 ) */