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/*
* FreeRTOS Kernel V10.3.1
* 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.
*
* http://www.FreeRTOS.org
* http://aws.amazon.com/freertos
*
* 1 tab == 4 spaces!
*/
#ifndef QUEUE_H
#define QUEUE_H
#ifndef INC_FREERTOS_H
#error "include FreeRTOS.h" must appear in source files before "include queue.h"
#endif
#ifdef __cplusplus
extern "C" {
#endif
#include "task.h"
struct QueueDefinition; /* Using old naming convention so as not to break kernel aware debuggers. */
typedef struct QueueDefinition * QueueHandle_t;
typedef struct QueueDefinition * QueueSetHandle_t;
typedef struct QueueDefinition * QueueSetMemberHandle_t;
/* For internal use only. */
#define queueSEND_TO_BACK ( ( BaseType_t ) 0 )
#define queueSEND_TO_FRONT ( ( BaseType_t ) 1 )
#define queueOVERWRITE ( ( BaseType_t ) 2 )
/* For internal use only. These definitions *must* match those in queue.c. */
#define queueQUEUE_TYPE_BASE ( ( uint8_t ) 0U )
#define queueQUEUE_TYPE_SET ( ( uint8_t ) 0U )
#define queueQUEUE_TYPE_MUTEX ( ( uint8_t ) 1U )
#define queueQUEUE_TYPE_COUNTING_SEMAPHORE ( ( uint8_t ) 2U )
#define queueQUEUE_TYPE_BINARY_SEMAPHORE ( ( uint8_t ) 3U )
#define queueQUEUE_TYPE_RECURSIVE_MUTEX ( ( uint8_t ) 4U )
#if( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
#define xQueueCreate( uxQueueLength, uxItemSize ) xQueueGenericCreate( ( uxQueueLength ), ( uxItemSize ), ( queueQUEUE_TYPE_BASE ) )
#endif
#if( configSUPPORT_STATIC_ALLOCATION == 1 )
#define xQueueCreateStatic( uxQueueLength, uxItemSize, pucQueueStorage, pxQueueBuffer ) xQueueGenericCreateStatic( ( uxQueueLength ), ( uxItemSize ), ( pucQueueStorage ), ( pxQueueBuffer ), ( queueQUEUE_TYPE_BASE ) )
#endif /* configSUPPORT_STATIC_ALLOCATION */
#define xQueueSendToFront( xQueue, pvItemToQueue, xTicksToWait ) xQueueGenericSend( ( xQueue ), ( pvItemToQueue ), ( xTicksToWait ), queueSEND_TO_FRONT )
#define xQueueSendToBack( xQueue, pvItemToQueue, xTicksToWait ) xQueueGenericSend( ( xQueue ), ( pvItemToQueue ), ( xTicksToWait ), queueSEND_TO_BACK )
#define xQueueSend( xQueue, pvItemToQueue, xTicksToWait ) xQueueGenericSend( ( xQueue ), ( pvItemToQueue ), ( xTicksToWait ), queueSEND_TO_BACK )
#define xQueueOverwrite( xQueue, pvItemToQueue ) xQueueGenericSend( ( xQueue ), ( pvItemToQueue ), 0, queueOVERWRITE )
BaseType_t xQueueGenericSend( QueueHandle_t xQueue, const void * const pvItemToQueue, TickType_t xTicksToWait, const BaseType_t xCopyPosition ) PRIVILEGED_FUNCTION;
BaseType_t xQueuePeek( QueueHandle_t xQueue, void * const pvBuffer, TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
BaseType_t xQueuePeekFromISR( QueueHandle_t xQueue, void * const pvBuffer ) PRIVILEGED_FUNCTION;
BaseType_t xQueueReceive( QueueHandle_t xQueue, void * const pvBuffer, TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
UBaseType_t uxQueueMessagesWaiting( const QueueHandle_t xQueue ) PRIVILEGED_FUNCTION;
UBaseType_t uxQueueSpacesAvailable( const QueueHandle_t xQueue ) PRIVILEGED_FUNCTION;
void vQueueDelete( QueueHandle_t xQueue ) PRIVILEGED_FUNCTION;
#define xQueueSendToFrontFromISR( xQueue, pvItemToQueue, pxHigherPriorityTaskWoken ) xQueueGenericSendFromISR( ( xQueue ), ( pvItemToQueue ), ( pxHigherPriorityTaskWoken ), queueSEND_TO_FRONT )
#define xQueueSendToBackFromISR( xQueue, pvItemToQueue, pxHigherPriorityTaskWoken ) xQueueGenericSendFromISR( ( xQueue ), ( pvItemToQueue ), ( pxHigherPriorityTaskWoken ), queueSEND_TO_BACK )
#define xQueueOverwriteFromISR( xQueue, pvItemToQueue, pxHigherPriorityTaskWoken ) xQueueGenericSendFromISR( ( xQueue ), ( pvItemToQueue ), ( pxHigherPriorityTaskWoken ), queueOVERWRITE )
#define xQueueSendFromISR( xQueue, pvItemToQueue, pxHigherPriorityTaskWoken ) xQueueGenericSendFromISR( ( xQueue ), ( pvItemToQueue ), ( pxHigherPriorityTaskWoken ), queueSEND_TO_BACK )
BaseType_t xQueueGenericSendFromISR( QueueHandle_t xQueue, const void * const pvItemToQueue, BaseType_t * const pxHigherPriorityTaskWoken, const BaseType_t xCopyPosition ) PRIVILEGED_FUNCTION;
BaseType_t xQueueGiveFromISR( QueueHandle_t xQueue, BaseType_t * const pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION;
BaseType_t xQueueReceiveFromISR( QueueHandle_t xQueue, void * const pvBuffer, BaseType_t * const pxHigherPriorityTaskWoken ) PRIVILEGED_FUNCTION;
/*
* Utilities to query queues that are safe to use from an ISR. These utilities
* should be used only from witin an ISR, or within a critical section.
*/
BaseType_t xQueueIsQueueEmptyFromISR( const QueueHandle_t xQueue ) PRIVILEGED_FUNCTION;
BaseType_t xQueueIsQueueFullFromISR( const QueueHandle_t xQueue ) PRIVILEGED_FUNCTION;
UBaseType_t uxQueueMessagesWaitingFromISR( const QueueHandle_t xQueue ) PRIVILEGED_FUNCTION;
/*
* The functions defined above are for passing data to and from tasks. The
* functions below are the equivalents for passing data to and from
* co-routines.
*
* These functions are called from the co-routine macro implementation and
* should not be called directly from application code. Instead use the macro
* wrappers defined within croutine.h.
*/
BaseType_t xQueueCRSendFromISR( QueueHandle_t xQueue, const void *pvItemToQueue, BaseType_t xCoRoutinePreviouslyWoken );
BaseType_t xQueueCRReceiveFromISR( QueueHandle_t xQueue, void *pvBuffer, BaseType_t *pxTaskWoken );
BaseType_t xQueueCRSend( QueueHandle_t xQueue, const void *pvItemToQueue, TickType_t xTicksToWait );
BaseType_t xQueueCRReceive( QueueHandle_t xQueue, void *pvBuffer, TickType_t xTicksToWait );
/*
* For internal use only. Use xSemaphoreCreateMutex(),
* xSemaphoreCreateCounting() or xSemaphoreGetMutexHolder() instead of calling
* these functions directly.
*/
QueueHandle_t xQueueCreateMutex( const uint8_t ucQueueType ) PRIVILEGED_FUNCTION;
QueueHandle_t xQueueCreateMutexStatic( const uint8_t ucQueueType, StaticQueue_t *pxStaticQueue ) PRIVILEGED_FUNCTION;
QueueHandle_t xQueueCreateCountingSemaphore( const UBaseType_t uxMaxCount, const UBaseType_t uxInitialCount ) PRIVILEGED_FUNCTION;
QueueHandle_t xQueueCreateCountingSemaphoreStatic( const UBaseType_t uxMaxCount, const UBaseType_t uxInitialCount, StaticQueue_t *pxStaticQueue ) PRIVILEGED_FUNCTION;
BaseType_t xQueueSemaphoreTake( QueueHandle_t xQueue, TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
TaskHandle_t xQueueGetMutexHolder( QueueHandle_t xSemaphore ) PRIVILEGED_FUNCTION;
TaskHandle_t xQueueGetMutexHolderFromISR( QueueHandle_t xSemaphore ) PRIVILEGED_FUNCTION;
/*
* For internal use only. Use xSemaphoreTakeMutexRecursive() or
* xSemaphoreGiveMutexRecursive() instead of calling these functions directly.
*/
BaseType_t xQueueTakeMutexRecursive( QueueHandle_t xMutex, TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
BaseType_t xQueueGiveMutexRecursive( QueueHandle_t xMutex ) PRIVILEGED_FUNCTION;
/*
* Reset a queue back to its original empty state. The return value is now
* obsolete and is always set to pdPASS.
*/
#define xQueueReset( xQueue ) xQueueGenericReset( xQueue, pdFALSE )
/*
* The registry is provided as a means for kernel aware debuggers to
* locate queues, semaphores and mutexes. Call vQueueAddToRegistry() add
* a queue, semaphore or mutex handle to the registry if you want the handle
* to be available to a kernel aware debugger. If you are not using a kernel
* aware debugger then this function can be ignored.
*
* configQUEUE_REGISTRY_SIZE defines the maximum number of handles the
* registry can hold. configQUEUE_REGISTRY_SIZE must be greater than 0
* within FreeRTOSConfig.h for the registry to be available. Its value
* does not effect the number of queues, semaphores and mutexes that can be
* created - just the number that the registry can hold.
*
* @param xQueue The handle of the queue being added to the registry. This
* is the handle returned by a call to xQueueCreate(). Semaphore and mutex
* handles can also be passed in here.
*
* @param pcName The name to be associated with the handle. This is the
* name that the kernel aware debugger will display. The queue registry only
* stores a pointer to the string - so the string must be persistent (global or
* preferably in ROM/Flash), not on the stack.
*/
#if( configQUEUE_REGISTRY_SIZE > 0 )
void vQueueAddToRegistry( QueueHandle_t xQueue, const char *pcQueueName ) PRIVILEGED_FUNCTION; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
#endif
/*
* The registry is provided as a means for kernel aware debuggers to
* locate queues, semaphores and mutexes. Call vQueueAddToRegistry() add
* a queue, semaphore or mutex handle to the registry if you want the handle
* to be available to a kernel aware debugger, and vQueueUnregisterQueue() to
* remove the queue, semaphore or mutex from the register. If you are not using
* a kernel aware debugger then this function can be ignored.
*
* @param xQueue The handle of the queue being removed from the registry.
*/
#if( configQUEUE_REGISTRY_SIZE > 0 )
void vQueueUnregisterQueue( QueueHandle_t xQueue ) PRIVILEGED_FUNCTION;
#endif
/*
* The queue registry is provided as a means for kernel aware debuggers to
* locate queues, semaphores and mutexes. Call pcQueueGetName() to look
* up and return the name of a queue in the queue registry from the queue's
* handle.
*
* @param xQueue The handle of the queue the name of which will be returned.
* @return If the queue is in the registry then a pointer to the name of the
* queue is returned. If the queue is not in the registry then NULL is
* returned.
*/
#if( configQUEUE_REGISTRY_SIZE > 0 )
const char *pcQueueGetName( QueueHandle_t xQueue ) PRIVILEGED_FUNCTION; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
#endif
/*
* Generic version of the function used to creaet a queue using dynamic memory
* allocation. This is called by other functions and macros that create other
* RTOS objects that use the queue structure as their base.
*/
#if( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
QueueHandle_t xQueueGenericCreate( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, const uint8_t ucQueueType ) PRIVILEGED_FUNCTION;
#endif
/*
* Generic version of the function used to creaet a queue using dynamic memory
* allocation. This is called by other functions and macros that create other
* RTOS objects that use the queue structure as their base.
*/
#if( configSUPPORT_STATIC_ALLOCATION == 1 )
QueueHandle_t xQueueGenericCreateStatic( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, uint8_t *pucQueueStorage, StaticQueue_t *pxStaticQueue, const uint8_t ucQueueType ) PRIVILEGED_FUNCTION;
#endif
/*
* Queue sets provide a mechanism to allow a task to block (pend) on a read
* operation from multiple queues or semaphores simultaneously.
*
* See FreeRTOS/Source/Demo/Common/Minimal/QueueSet.c for an example using this
* function.
*
* A queue set must be explicitly created using a call to xQueueCreateSet()
* before it can be used. Once created, standard FreeRTOS queues and semaphores
* can be added to the set using calls to xQueueAddToSet().
* xQueueSelectFromSet() is then used to determine which, if any, of the queues
* or semaphores contained in the set is in a state where a queue read or
* semaphore take operation would be successful.
*
* Note 1: See the documentation on http://wwwFreeRTOS.org/RTOS-queue-sets.html
* for reasons why queue sets are very rarely needed in practice as there are
* simpler methods of blocking on multiple objects.
*
* Note 2: Blocking on a queue set that contains a mutex will not cause the
* mutex holder to inherit the priority of the blocked task.
*
* Note 3: An additional 4 bytes of RAM is required for each space in a every
* queue added to a queue set. Therefore counting semaphores that have a high
* maximum count value should not be added to a queue set.
*
* Note 4: A receive (in the case of a queue) or take (in the case of a
* semaphore) operation must not be performed on a member of a queue set unless
* a call to xQueueSelectFromSet() has first returned a handle to that set member.
*
* @param uxEventQueueLength Queue sets store events that occur on
* the queues and semaphores contained in the set. uxEventQueueLength specifies
* the maximum number of events that can be queued at once. To be absolutely
* certain that events are not lost uxEventQueueLength should be set to the
* total sum of the length of the queues added to the set, where binary
* semaphores and mutexes have a length of 1, and counting semaphores have a
* length set by their maximum count value. Examples:
* + If a queue set is to hold a queue of length 5, another queue of length 12,
* and a binary semaphore, then uxEventQueueLength should be set to
* (5 + 12 + 1), or 18.
* + If a queue set is to hold three binary semaphores then uxEventQueueLength
* should be set to (1 + 1 + 1 ), or 3.
* + If a queue set is to hold a counting semaphore that has a maximum count of
* 5, and a counting semaphore that has a maximum count of 3, then
* uxEventQueueLength should be set to (5 + 3), or 8.
*
* @return If the queue set is created successfully then a handle to the created
* queue set is returned. Otherwise NULL is returned.
*/
QueueSetHandle_t xQueueCreateSet( const UBaseType_t uxEventQueueLength ) PRIVILEGED_FUNCTION;
/*
* Adds a queue or semaphore to a queue set that was previously created by a
* call to xQueueCreateSet().
*
* See FreeRTOS/Source/Demo/Common/Minimal/QueueSet.c for an example using this
* function.
*
* Note 1: A receive (in the case of a queue) or take (in the case of a
* semaphore) operation must not be performed on a member of a queue set unless
* a call to xQueueSelectFromSet() has first returned a handle to that set member.
*
* @param xQueueOrSemaphore The handle of the queue or semaphore being added to
* the queue set (cast to an QueueSetMemberHandle_t type).
*
* @param xQueueSet The handle of the queue set to which the queue or semaphore
* is being added.
*
* @return If the queue or semaphore was successfully added to the queue set
* then pdPASS is returned. If the queue could not be successfully added to the
* queue set because it is already a member of a different queue set then pdFAIL
* is returned.
*/
BaseType_t xQueueAddToSet( QueueSetMemberHandle_t xQueueOrSemaphore, QueueSetHandle_t xQueueSet ) PRIVILEGED_FUNCTION;
/*
* Removes a queue or semaphore from a queue set. A queue or semaphore can only
* be removed from a set if the queue or semaphore is empty.
*
* See FreeRTOS/Source/Demo/Common/Minimal/QueueSet.c for an example using this
* function.
*
* @param xQueueOrSemaphore The handle of the queue or semaphore being removed
* from the queue set (cast to an QueueSetMemberHandle_t type).
*
* @param xQueueSet The handle of the queue set in which the queue or semaphore
* is included.
*
* @return If the queue or semaphore was successfully removed from the queue set
* then pdPASS is returned. If the queue was not in the queue set, or the
* queue (or semaphore) was not empty, then pdFAIL is returned.
*/
BaseType_t xQueueRemoveFromSet( QueueSetMemberHandle_t xQueueOrSemaphore, QueueSetHandle_t xQueueSet ) PRIVILEGED_FUNCTION;
/*
* xQueueSelectFromSet() selects from the members of a queue set a queue or
* semaphore that either contains data (in the case of a queue) or is available
* to take (in the case of a semaphore). xQueueSelectFromSet() effectively
* allows a task to block (pend) on a read operation on all the queues and
* semaphores in a queue set simultaneously.
*
* See FreeRTOS/Source/Demo/Common/Minimal/QueueSet.c for an example using this
* function.
*
* Note 1: See the documentation on http://wwwFreeRTOS.org/RTOS-queue-sets.html
* for reasons why queue sets are very rarely needed in practice as there are
* simpler methods of blocking on multiple objects.
*
* Note 2: Blocking on a queue set that contains a mutex will not cause the
* mutex holder to inherit the priority of the blocked task.
*
* Note 3: A receive (in the case of a queue) or take (in the case of a
* semaphore) operation must not be performed on a member of a queue set unless
* a call to xQueueSelectFromSet() has first returned a handle to that set member.
*
* @param xQueueSet The queue set on which the task will (potentially) block.
*
* @param xTicksToWait The maximum time, in ticks, that the calling task will
* remain in the Blocked state (with other tasks executing) to wait for a member
* of the queue set to be ready for a successful queue read or semaphore take
* operation.
*
* @return xQueueSelectFromSet() will return the handle of a queue (cast to
* a QueueSetMemberHandle_t type) contained in the queue set that contains data,
* or the handle of a semaphore (cast to a QueueSetMemberHandle_t type) contained
* in the queue set that is available, or NULL if no such queue or semaphore
* exists before before the specified block time expires.
*/
QueueSetMemberHandle_t xQueueSelectFromSet( QueueSetHandle_t xQueueSet, const TickType_t xTicksToWait ) PRIVILEGED_FUNCTION;
/*
* A version of xQueueSelectFromSet() that can be used from an ISR.
*/
QueueSetMemberHandle_t xQueueSelectFromSetFromISR( QueueSetHandle_t xQueueSet ) PRIVILEGED_FUNCTION;
/* Not public API functions. */
void vQueueWaitForMessageRestricted( QueueHandle_t xQueue, TickType_t xTicksToWait, const BaseType_t xWaitIndefinitely ) PRIVILEGED_FUNCTION;
BaseType_t xQueueGenericReset( QueueHandle_t xQueue, BaseType_t xNewQueue ) PRIVILEGED_FUNCTION;
void vQueueSetQueueNumber( QueueHandle_t xQueue, UBaseType_t uxQueueNumber ) PRIVILEGED_FUNCTION;
UBaseType_t uxQueueGetQueueNumber( QueueHandle_t xQueue ) PRIVILEGED_FUNCTION;
uint8_t ucQueueGetQueueType( QueueHandle_t xQueue ) PRIVILEGED_FUNCTION;
#ifdef __cplusplus
}
#endif
#endif /* QUEUE_H */