esp-idf/components/freertos/queue.c

/*
    FreeRTOS V8.2.0 - Copyright (C) 2015 Real Time Engineers Ltd.
    All rights reserved

    VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

    This file is part of the FreeRTOS distribution.

    FreeRTOS is free software; you can redistribute it and/or modify it under
    the terms of the GNU General Public License (version 2) as published by the
    Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception.

	***************************************************************************
    >>!   NOTE: The modification to the GPL is included to allow you to     !<<
    >>!   distribute a combined work that includes FreeRTOS without being   !<<
    >>!   obliged to provide the source code for proprietary components     !<<
    >>!   outside of the FreeRTOS kernel.                                   !<<
	***************************************************************************

    FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
    FOR A PARTICULAR PURPOSE.  Full license text is available on the following
    link: http://www.freertos.org/a00114.html

    ***************************************************************************
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*/



/*
 ToDo: The multicore implementation of this uses taskENTER_CRITICAL etc to make sure the 
 queue structures aren't accessed by another processor or core. It would be useful to have
 IRQs be able to schedule stuff while doing task-related stuff, meaning we have to convert
 the taskENTER_CRITICAL stuff to a lock + a scheduler suspend instead.
*/

#include <stdlib.h>
#include <string.h>

#include "rom/ets_sys.h"

/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
all the API functions to use the MPU wrappers.  That should only be done when
task.h is included from an application file. */
#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE

#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

#if ( configUSE_CO_ROUTINES == 1 )
	#include "croutine.h"
#endif

/* Lint e961 and e750 are suppressed as a MISRA exception justified because the
MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined for the
header files above, but not in this file, in order to generate the correct
privileged Vs unprivileged linkage and placement. */
#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*lint !e961 !e750. */

/* When the Queue_t structure is used to represent a base queue its pcHead and
pcTail members are used as pointers into the queue storage area.  When the
Queue_t structure is used to represent a mutex pcHead and pcTail pointers are
not necessary, and the pcHead pointer is set to NULL to indicate that the
pcTail pointer actually points to the mutex holder (if any).  Map alternative
names to the pcHead and pcTail structure members to ensure the readability of
the code is maintained despite this dual use of two structure members.  An
alternative implementation would be to use a union, but use of a union is
against the coding standard (although an exception to the standard has been
permitted where the dual use also significantly changes the type of the
structure member). */
#define pxMutexHolder					pcTail
#define uxQueueType						pcHead
#define queueQUEUE_IS_MUTEX				NULL

/* Semaphores do not actually store or copy data, so have an item size of
zero. */
#define queueSEMAPHORE_QUEUE_ITEM_LENGTH ( ( UBaseType_t ) 0 )
#define queueMUTEX_GIVE_BLOCK_TIME		 ( ( TickType_t ) 0U )

#if( configUSE_PREEMPTION == 0 )
	/* If the cooperative scheduler is being used then a yield should not be
	performed just because a higher priority task has been woken. */
	#define queueYIELD_IF_USING_PREEMPTION_MUX()
	#define queueYIELD_IF_USING_PREEMPTION()
#else
	#define queueYIELD_IF_USING_PREEMPTION() portYIELD_WITHIN_API()
	#define queueYIELD_IF_USING_PREEMPTION_MUX(mux) { \
					taskEXIT_CRITICAL(mux); \
					portYIELD_WITHIN_API(); \
					taskENTER_CRITICAL(mux); \
					} while(0)
#endif

/*
 * Definition of the queue used by the scheduler.
 * Items are queued by copy, not reference.  See the following link for the
 * rationale: http://www.freertos.org/Embedded-RTOS-Queues.html
 */
typedef struct QueueDefinition
{
	int8_t *pcHead;					/*< Points to the beginning of the queue storage area. */
	int8_t *pcTail;					/*< Points to the byte at the end of the queue storage area.  Once more byte is allocated than necessary to store the queue items, this is used as a marker. */
	int8_t *pcWriteTo;				/*< Points to the free next place in the storage area. */

	union							/* Use of a union is an exception to the coding standard to ensure two mutually exclusive structure members don't appear simultaneously (wasting RAM). */
	{
		int8_t *pcReadFrom;			/*< Points to the last place that a queued item was read from when the structure is used as a queue. */
		UBaseType_t uxRecursiveCallCount;/*< Maintains a count of the number of times a recursive mutex has been recursively 'taken' when the structure is used as a mutex. */
	} u;

	List_t xTasksWaitingToSend;		/*< List of tasks that are blocked waiting to post onto this queue.  Stored in priority order. */
	List_t xTasksWaitingToReceive;	/*< List of tasks that are blocked waiting to read from this queue.  Stored in priority order. */

	volatile UBaseType_t uxMessagesWaiting;/*< The number of items currently in the queue. */
	UBaseType_t uxLength;			/*< The length of the queue defined as the number of items it will hold, not the number of bytes. */
	UBaseType_t uxItemSize;			/*< The size of each items that the queue will hold. */

	#if( ( configSUPPORT_STATIC_ALLOCATION == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
		uint8_t ucStaticallyAllocated;	/*< Set to pdTRUE if the memory used by the queue was statically allocated to ensure no attempt is made to free the memory. */
	#endif

	#if ( configUSE_QUEUE_SETS == 1 )
		struct QueueDefinition *pxQueueSetContainer;
	#endif

    #if ( configUSE_TRACE_FACILITY == 1 )
		UBaseType_t uxQueueNumber;
		uint8_t ucQueueType;
	#endif

	portMUX_TYPE mux;

} xQUEUE;

/* The old xQUEUE name is maintained above then typedefed to the new Queue_t
name below to enable the use of older kernel aware debuggers. */
typedef xQUEUE Queue_t;

#if __GNUC_PREREQ(4, 6)
_Static_assert(sizeof(StaticQueue_t) == sizeof(Queue_t), "StaticQueue_t != Queue_t");
#endif


/*-----------------------------------------------------------*/

/*
 * The queue registry is just a means for kernel aware debuggers to locate
 * queue structures.  It has no other purpose so is an optional component.
 */
#if ( configQUEUE_REGISTRY_SIZE > 0 )

	/* The type stored within the queue registry array.  This allows a name
	to be assigned to each queue making kernel aware debugging a little
	more user friendly. */
	typedef struct QUEUE_REGISTRY_ITEM
	{
		const char *pcQueueName; /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
		QueueHandle_t xHandle;
	} xQueueRegistryItem;

	/* The old xQueueRegistryItem name is maintained above then typedefed to the
	new xQueueRegistryItem name below to enable the use of older kernel aware
	debuggers. */
	typedef xQueueRegistryItem QueueRegistryItem_t;

	/* The queue registry is simply an array of QueueRegistryItem_t structures.
	The pcQueueName member of a structure being NULL is indicative of the
	array position being vacant. */
	QueueRegistryItem_t xQueueRegistry[ configQUEUE_REGISTRY_SIZE ];

#endif /* configQUEUE_REGISTRY_SIZE */


/*
 * Uses a critical section to determine if there is any data in a queue.
 *
 * @return pdTRUE if the queue contains no items, otherwise pdFALSE.
 */
static BaseType_t prvIsQueueEmpty( Queue_t *pxQueue ) PRIVILEGED_FUNCTION;

/*
 * Uses a critical section to determine if there is any space in a queue.
 *
 * @return pdTRUE if there is no space, otherwise pdFALSE;
 */
static BaseType_t prvIsQueueFull( Queue_t *pxQueue ) PRIVILEGED_FUNCTION;

/*
 * Copies an item into the queue, either at the front of the queue or the
 * back of the queue.
 */
static BaseType_t prvCopyDataToQueue( Queue_t * const pxQueue, const void *pvItemToQueue, const BaseType_t xPosition ) PRIVILEGED_FUNCTION;

/*
 * Copies an item out of a queue.
 */
static void prvCopyDataFromQueue( Queue_t * const pxQueue, void * const pvBuffer ) PRIVILEGED_FUNCTION;

#if ( configUSE_QUEUE_SETS == 1 )
	/*
	 * Checks to see if a queue is a member of a queue set, and if so, notifies
	 * the queue set that the queue contains data.
	 */
	static BaseType_t prvNotifyQueueSetContainer( const Queue_t * const pxQueue, const BaseType_t xCopyPosition ) PRIVILEGED_FUNCTION;
#endif

/*
 * Called after a Queue_t structure has been allocated either statically or
 * dynamically to fill in the structure's members.
 */
static void prvInitialiseNewQueue( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, uint8_t *pucQueueStorage, const uint8_t ucQueueType, Queue_t *pxNewQueue ) PRIVILEGED_FUNCTION;

/*
 * Mutexes are a special type of queue.  When a mutex is created, first the
 * queue is created, then prvInitialiseMutex() is called to configure the queue
 * as a mutex.
 */
#if( configUSE_MUTEXES == 1 )
	static void prvInitialiseMutex( Queue_t *pxNewQueue ) PRIVILEGED_FUNCTION;
#endif

BaseType_t xQueueGenericReset( QueueHandle_t xQueue, BaseType_t xNewQueue )
{
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( pxQueue );

	if ( xNewQueue == pdTRUE ) 
	{
		vPortCPUInitializeMutex(&pxQueue->mux);
	}
	taskENTER_CRITICAL(&pxQueue->mux);
	{
		pxQueue->pcTail = pxQueue->pcHead + ( pxQueue->uxLength * pxQueue->uxItemSize );
		pxQueue->uxMessagesWaiting = ( UBaseType_t ) 0U;
		pxQueue->pcWriteTo = pxQueue->pcHead;
		pxQueue->u.pcReadFrom = pxQueue->pcHead + ( ( pxQueue->uxLength - ( UBaseType_t ) 1U ) * pxQueue->uxItemSize );

		if( xNewQueue == pdFALSE )
		{
			/* If there are tasks blocked waiting to read from the queue, then
			the tasks will remain blocked as after this function exits the queue
			will still be empty.  If there are tasks blocked waiting to write to
			the queue, then one should be unblocked as after this function exits
			it will be possible to write to it. */
			if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
			{
				if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )
				{
					queueYIELD_IF_USING_PREEMPTION_MUX(&pxQueue->mux);
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}
		}
		else
		{
			/* Ensure the event queues start in the correct state. */
			vListInitialise( &( pxQueue->xTasksWaitingToSend ) );
			vListInitialise( &( pxQueue->xTasksWaitingToReceive ) );
		}
	}
	taskEXIT_CRITICAL(&pxQueue->mux);

	/* A value is returned for calling semantic consistency with previous
	versions. */
	return pdPASS;
}
/*-----------------------------------------------------------*/

#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 )
	{
	Queue_t *pxNewQueue;

		configASSERT( uxQueueLength > ( UBaseType_t ) 0 );

		/* The StaticQueue_t structure and the queue storage area must be
		supplied. */
		configASSERT( pxStaticQueue != NULL );

		/* A queue storage area should be provided if the item size is not 0, and
		should not be provided if the item size is 0. */
		configASSERT( !( ( pucQueueStorage != NULL ) && ( uxItemSize == 0 ) ) );
		configASSERT( !( ( pucQueueStorage == NULL ) && ( uxItemSize != 0 ) ) );

		#if( configASSERT_DEFINED == 1 )
		{
			/* Sanity check that the size of the structure used to declare a
			variable of type StaticQueue_t or StaticSemaphore_t equals the size of
			the real queue and semaphore structures. */
			volatile size_t xSize = sizeof( StaticQueue_t );
			configASSERT( xSize == sizeof( Queue_t ) );
		}
		#endif /* configASSERT_DEFINED */

		/* The address of a statically allocated queue was passed in, use it.
		The address of a statically allocated storage area was also passed in
		but is already set. */
		pxNewQueue = ( Queue_t * ) pxStaticQueue; /*lint !e740 Unusual cast is ok as the structures are designed to have the same alignment, and the size is checked by an assert. */

		if( pxNewQueue != NULL )
		{
			#if( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
			{
				/* Queues can be allocated wither statically or dynamically, so
				note this queue was allocated statically in case the queue is
				later deleted. */
				pxNewQueue->ucStaticallyAllocated = pdTRUE;
			}
			#endif /* configSUPPORT_DYNAMIC_ALLOCATION */

			prvInitialiseNewQueue( uxQueueLength, uxItemSize, pucQueueStorage, ucQueueType, pxNewQueue );
		}

		return pxNewQueue;
	}

#endif /* configSUPPORT_STATIC_ALLOCATION */
/*-----------------------------------------------------------*/

#if( configSUPPORT_DYNAMIC_ALLOCATION == 1 )

	QueueHandle_t xQueueGenericCreate( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, const uint8_t ucQueueType )
	{
	Queue_t *pxNewQueue;
	size_t xQueueSizeInBytes;
	uint8_t *pucQueueStorage;

		configASSERT( uxQueueLength > ( UBaseType_t ) 0 );

		if( uxItemSize == ( UBaseType_t ) 0 )
		{
			/* There is not going to be a queue storage area. */
			xQueueSizeInBytes = ( size_t ) 0;
		}
		else
		{
			/* Allocate enough space to hold the maximum number of items that
			can be in the queue at any time. */
			xQueueSizeInBytes = ( size_t ) ( uxQueueLength * uxItemSize ); /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
		}

		pxNewQueue = ( Queue_t * ) pvPortMalloc( sizeof( Queue_t ) + xQueueSizeInBytes );

		if( pxNewQueue != NULL )
		{
			/* Jump past the queue structure to find the location of the queue
			storage area. */
			pucQueueStorage = ( ( uint8_t * ) pxNewQueue ) + sizeof( Queue_t );

			#if( configSUPPORT_STATIC_ALLOCATION == 1 )
			{
				/* Queues can be created either statically or dynamically, so
				note this task was created dynamically in case it is later
				deleted. */
				pxNewQueue->ucStaticallyAllocated = pdFALSE;
			}
			#endif /* configSUPPORT_STATIC_ALLOCATION */

			prvInitialiseNewQueue( uxQueueLength, uxItemSize, pucQueueStorage, ucQueueType, pxNewQueue );
		}

		return pxNewQueue;
	}

#endif /* configSUPPORT_STATIC_ALLOCATION */
/*-----------------------------------------------------------*/

static void prvInitialiseNewQueue( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, uint8_t *pucQueueStorage, const uint8_t ucQueueType, Queue_t *pxNewQueue )
{
	/* Remove compiler warnings about unused parameters should
	configUSE_TRACE_FACILITY not be set to 1. */
	( void ) ucQueueType;

	if( uxItemSize == ( UBaseType_t ) 0 )
	{
		/* No RAM was allocated for the queue storage area, but PC head cannot
		be set to NULL because NULL is used as a key to say the queue is used as
		a mutex.  Therefore just set pcHead to point to the queue as a benign
		value that is known to be within the memory map. */
		pxNewQueue->pcHead = ( int8_t * ) pxNewQueue;
	}
	else
	{
		/* Set the head to the start of the queue storage area. */
		pxNewQueue->pcHead = ( int8_t * ) pucQueueStorage;
	}

	/* Initialise the queue members as described where the queue type is
	defined. */
	pxNewQueue->uxLength = uxQueueLength;
	pxNewQueue->uxItemSize = uxItemSize;
	( void ) xQueueGenericReset( pxNewQueue, pdTRUE );

	#if ( configUSE_TRACE_FACILITY == 1 )
	{
		pxNewQueue->ucQueueType = ucQueueType;
	}
	#endif /* configUSE_TRACE_FACILITY */

	#if( configUSE_QUEUE_SETS == 1 )
	{
		pxNewQueue->pxQueueSetContainer = NULL;
	}
	#endif /* configUSE_QUEUE_SETS */

	traceQUEUE_CREATE( pxNewQueue );
}
/*-----------------------------------------------------------*/

#if( configUSE_MUTEXES == 1 )

	static void prvInitialiseMutex( Queue_t *pxNewQueue )
	{
		if( pxNewQueue != NULL )
		{
			/* The queue create function will set all the queue structure members
			correctly for a generic queue, but this function is creating a
			mutex.  Overwrite those members that need to be set differently -
			in particular the information required for priority inheritance. */
			pxNewQueue->pxMutexHolder = NULL;
			pxNewQueue->uxQueueType = queueQUEUE_IS_MUTEX;

			/* In case this is a recursive mutex. */
			pxNewQueue->u.uxRecursiveCallCount = 0;

            vPortCPUInitializeMutex(&pxNewQueue->mux);

			traceCREATE_MUTEX( pxNewQueue );

			/* Start with the semaphore in the expected state. */
			( void ) xQueueGenericSend( pxNewQueue, NULL, ( TickType_t ) 0U, queueSEND_TO_BACK );
		}
		else
		{
			traceCREATE_MUTEX_FAILED();
		}
	}

#endif /* configUSE_MUTEXES */
/*-----------------------------------------------------------*/

#if( ( configUSE_MUTEXES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )

	QueueHandle_t xQueueCreateMutex( const uint8_t ucQueueType )
	{
	Queue_t *pxNewQueue;
	const UBaseType_t uxMutexLength = ( UBaseType_t ) 1, uxMutexSize = ( UBaseType_t ) 0;

		pxNewQueue = ( Queue_t * ) xQueueGenericCreate( uxMutexLength, uxMutexSize, ucQueueType );
		prvInitialiseMutex( pxNewQueue );

		return pxNewQueue;
	}

#endif /* configUSE_MUTEXES */
/*-----------------------------------------------------------*/

#if( ( configUSE_MUTEXES == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )

	QueueHandle_t xQueueCreateMutexStatic( const uint8_t ucQueueType, StaticQueue_t *pxStaticQueue )
	{
	Queue_t *pxNewQueue;
	const UBaseType_t uxMutexLength = ( UBaseType_t ) 1, uxMutexSize = ( UBaseType_t ) 0;

		/* Prevent compiler warnings about unused parameters if
		configUSE_TRACE_FACILITY does not equal 1. */
		( void ) ucQueueType;

		pxNewQueue = ( Queue_t * ) xQueueGenericCreateStatic( uxMutexLength, uxMutexSize, NULL, pxStaticQueue, ucQueueType );
		prvInitialiseMutex( pxNewQueue );

		return pxNewQueue;
	}

#endif /* configUSE_MUTEXES */
/*-----------------------------------------------------------*/

#if ( ( configUSE_MUTEXES == 1 ) && ( INCLUDE_xSemaphoreGetMutexHolder == 1 ) )

	void* xQueueGetMutexHolder( QueueHandle_t xSemaphore )
	{
		Queue_t * const pxQueue = ( Queue_t * ) xSemaphore;
		void *pxReturn;

		/* This function is called by xSemaphoreGetMutexHolder(), and should not
		be called directly.  Note:  This is a good way of determining if the
		calling task is the mutex holder, but not a good way of determining the
		identity of the mutex holder, as the holder may change between the
		following critical section exiting and the function returning. */
		taskENTER_CRITICAL(&pxQueue->mux);
		{
			if( ( ( Queue_t * ) xSemaphore )->uxQueueType == queueQUEUE_IS_MUTEX )
			{
				pxReturn = ( void * ) ( ( Queue_t * ) xSemaphore )->pxMutexHolder;
			}
			else
			{
				pxReturn = NULL;
			}
		}
		taskEXIT_CRITICAL(&pxQueue->mux);

		return pxReturn;
	} /*lint !e818 xSemaphore cannot be a pointer to const because it is a typedef. */

#endif
/*-----------------------------------------------------------*/

#if ( configUSE_RECURSIVE_MUTEXES == 1 )

	BaseType_t xQueueGiveMutexRecursive( QueueHandle_t xMutex )
	{
	BaseType_t xReturn;
	Queue_t * const pxMutex = ( Queue_t * ) xMutex;

		configASSERT( pxMutex );

		/* If this is the task that holds the mutex then pxMutexHolder will not
		change outside of this task.  If this task does not hold the mutex then
		pxMutexHolder can never coincidentally equal the tasks handle, and as
		this is the only condition we are interested in it does not matter if
		pxMutexHolder is accessed simultaneously by another task.  Therefore no
		mutual exclusion is required to test the pxMutexHolder variable. */
		if( pxMutex->pxMutexHolder == ( void * ) xTaskGetCurrentTaskHandle() ) /*lint !e961 Not a redundant cast as TaskHandle_t is a typedef. */
		{
			traceGIVE_MUTEX_RECURSIVE( pxMutex );

			/* uxRecursiveCallCount cannot be zero if pxMutexHolder is equal to
			the task handle, therefore no underflow check is required.  Also,
			uxRecursiveCallCount is only modified by the mutex holder, and as
			there can only be one, no mutual exclusion is required to modify the
			uxRecursiveCallCount member. */
			( pxMutex->u.uxRecursiveCallCount )--;

			/* Have we unwound the call count? */
			if( pxMutex->u.uxRecursiveCallCount == ( UBaseType_t ) 0 )
			{
				/* Return the mutex.  This will automatically unblock any other
				task that might be waiting to access the mutex. */
				( void ) xQueueGenericSend( pxMutex, NULL, queueMUTEX_GIVE_BLOCK_TIME, queueSEND_TO_BACK );
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}

			xReturn = pdPASS;
		}
		else
		{
			/* The mutex cannot be given because the calling task is not the
			holder. */
			xReturn = pdFAIL;

			traceGIVE_MUTEX_RECURSIVE_FAILED( pxMutex );
		}

		return xReturn;
	}

#endif /* configUSE_RECURSIVE_MUTEXES */
/*-----------------------------------------------------------*/

#if ( configUSE_RECURSIVE_MUTEXES == 1 )

	BaseType_t xQueueTakeMutexRecursive( QueueHandle_t xMutex, TickType_t xTicksToWait )
	{
	BaseType_t xReturn;
	Queue_t * const pxMutex = ( Queue_t * ) xMutex;

		configASSERT( pxMutex );

		/* Comments regarding mutual exclusion as per those within
		xQueueGiveMutexRecursive(). */

		traceTAKE_MUTEX_RECURSIVE( pxMutex );

		if( pxMutex->pxMutexHolder == ( void * ) xTaskGetCurrentTaskHandle() ) /*lint !e961 Cast is not redundant as TaskHandle_t is a typedef. */
		{
			( pxMutex->u.uxRecursiveCallCount )++;
			xReturn = pdPASS;
		}
		else
		{
			xReturn = xQueueGenericReceive( pxMutex, NULL, xTicksToWait, pdFALSE );

			/* pdPASS will only be returned if the mutex was successfully
			obtained.  The calling task may have entered the Blocked state
			before reaching here. */
			if( xReturn == pdPASS )
			{
				( pxMutex->u.uxRecursiveCallCount )++;
			}
			else
			{
				traceTAKE_MUTEX_RECURSIVE_FAILED( pxMutex );
			}
		}

		return xReturn;
	}

#endif /* configUSE_RECURSIVE_MUTEXES */
/*-----------------------------------------------------------*/

#if( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )

	QueueHandle_t xQueueCreateCountingSemaphoreStatic( const UBaseType_t uxMaxCount, const UBaseType_t uxInitialCount, StaticQueue_t *pxStaticQueue )
	{
	QueueHandle_t xHandle;

		configASSERT( uxMaxCount != 0 );
		configASSERT( uxInitialCount <= uxMaxCount );

		xHandle = xQueueGenericCreateStatic( uxMaxCount, queueSEMAPHORE_QUEUE_ITEM_LENGTH, NULL, pxStaticQueue, queueQUEUE_TYPE_COUNTING_SEMAPHORE );

		if( xHandle != NULL )
		{
			( ( Queue_t * ) xHandle )->uxMessagesWaiting = uxInitialCount;

			traceCREATE_COUNTING_SEMAPHORE();
		}
		else
		{
			traceCREATE_COUNTING_SEMAPHORE_FAILED();
		}

		return xHandle;
	}

#endif /* ( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) ) */
/*-----------------------------------------------------------*/

#if( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )

	QueueHandle_t xQueueCreateCountingSemaphore( const UBaseType_t uxMaxCount, const UBaseType_t uxInitialCount )
	{
	QueueHandle_t xHandle;

		configASSERT( uxMaxCount != 0 );
		configASSERT( uxInitialCount <= uxMaxCount );

		xHandle = xQueueGenericCreate( uxMaxCount, queueSEMAPHORE_QUEUE_ITEM_LENGTH, queueQUEUE_TYPE_COUNTING_SEMAPHORE );

		if( xHandle != NULL )
		{
			( ( Queue_t * ) xHandle )->uxMessagesWaiting = uxInitialCount;

			traceCREATE_COUNTING_SEMAPHORE();
		}
		else
		{
			traceCREATE_COUNTING_SEMAPHORE_FAILED();
		}

		configASSERT( xHandle );
		return xHandle;
	}

#endif /* ( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) ) */
/*-----------------------------------------------------------*/

BaseType_t xQueueGenericSend( QueueHandle_t xQueue, const void * const pvItemToQueue, TickType_t xTicksToWait, const BaseType_t xCopyPosition )
{
BaseType_t xEntryTimeSet = pdFALSE, xYieldRequired;
TimeOut_t xTimeOut;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( pxQueue );
	configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
	configASSERT( !( ( xCopyPosition == queueOVERWRITE ) && ( pxQueue->uxLength != 1 ) ) );
	#if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) || ( configUSE_TIMERS == 1 ) )
	{
		configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
	}
	#endif


	/* This function relaxes the coding standard somewhat to allow return
	statements within the function itself.  This is done in the interest
	of execution time efficiency. */
	for( ;; )
	{
		taskENTER_CRITICAL(&pxQueue->mux);
		{
			/* Is there room on the queue now?  The running task must be
			the highest priority task wanting to access the queue.  If
			the head item in the queue is to be overwritten then it does
			not matter if the queue is full. */
			if( ( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) || ( xCopyPosition == queueOVERWRITE ) )
			{
				traceQUEUE_SEND( pxQueue );
				xYieldRequired = prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );

				#if ( configUSE_QUEUE_SETS == 1 )
				{
					if( pxQueue->pxQueueSetContainer != NULL )
					{
						if( prvNotifyQueueSetContainer( pxQueue, xCopyPosition ) == pdTRUE )
						{
							/* The queue is a member of a queue set, and posting
							to the queue set caused a higher priority task to
							unblock. A context switch is required. */
							queueYIELD_IF_USING_PREEMPTION_MUX(&pxQueue->mux);
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						/* If there was a task waiting for data to arrive on the
						queue then unblock it now. */
						if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
						{
							if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )
							{
								/* The unblocked task has a priority higher than
								our own so yield immediately.  Yes it is ok to
								do this from within the critical section - the
								kernel takes care of that. */
								queueYIELD_IF_USING_PREEMPTION_MUX(&pxQueue->mux);
							}
							else
							{
								mtCOVERAGE_TEST_MARKER();
							}
						}
						else if( xYieldRequired != pdFALSE )
						{
							/* This path is a special case that will only get
							executed if the task was holding multiple mutexes
							and the mutexes were given back in an order that is
							different to that in which they were taken. */
							queueYIELD_IF_USING_PREEMPTION_MUX(&pxQueue->mux);
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
				}
				#else /* configUSE_QUEUE_SETS */
				{
					/* If there was a task waiting for data to arrive on the
					queue then unblock it now. */
					if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
					{
						if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )
						{
							/* The unblocked task has a priority higher than
							our own so yield immediately.  Yes it is ok to do
							this from within the critical section - the kernel
							takes care of that. */
							queueYIELD_IF_USING_PREEMPTION_MUX(&pxQueue->mux);
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else if( xYieldRequired != pdFALSE )
					{
						/* This path is a special case that will only get
						executed if the task was holding multiple mutexes and
						the mutexes were given back in an order that is
						different to that in which they were taken. */
						queueYIELD_IF_USING_PREEMPTION_MUX(&pxQueue->mux);
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				#endif /* configUSE_QUEUE_SETS */

				taskEXIT_CRITICAL(&pxQueue->mux);
				return pdPASS;
			}
			else
			{
				if( xTicksToWait == ( TickType_t ) 0 )
				{
					/* The queue was full and no block time is specified (or
					the block time has expired) so leave now. */
					taskEXIT_CRITICAL(&pxQueue->mux);

					/* Return to the original privilege level before exiting
					the function. */
					traceQUEUE_SEND_FAILED( pxQueue );
					return errQUEUE_FULL;
				}
				else if( xEntryTimeSet == pdFALSE )
				{
					/* The queue was full and a block time was specified so
					configure the timeout structure. */
					vTaskSetTimeOutState( &xTimeOut );
					xEntryTimeSet = pdTRUE;
				}
				else
				{
					/* Entry time was already set. */
					mtCOVERAGE_TEST_MARKER();
				}
			}
		}
		taskEXIT_CRITICAL(&pxQueue->mux);

		/* Interrupts and other tasks can send to and receive from the queue
		now the critical section has been exited. */

		taskENTER_CRITICAL(&pxQueue->mux);

		/* Update the timeout state to see if it has expired yet. */
		if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
		{
			if( prvIsQueueFull( pxQueue ) != pdFALSE )
			{
				traceBLOCKING_ON_QUEUE_SEND( pxQueue );
				vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );


				/* Resuming the scheduler will move tasks from the pending
				ready list into the ready list - so it is feasible that this
				task is already in a ready list before it yields - in which
				case the yield will not cause a context switch unless there
				is also a higher priority task in the pending ready list. */
				taskEXIT_CRITICAL(&pxQueue->mux);
				portYIELD_WITHIN_API();
			}
			else
			{
				/* Try again. */
				taskEXIT_CRITICAL(&pxQueue->mux);
			}
		}
		else
		{
			/* The timeout has expired. */
			taskEXIT_CRITICAL(&pxQueue->mux);

			/* Return to the original privilege level before exiting the
			function. */
			traceQUEUE_SEND_FAILED( pxQueue );
			return errQUEUE_FULL;
		}
	}
}
/*-----------------------------------------------------------*/

#if ( configUSE_ALTERNATIVE_API == 1 )

	BaseType_t xQueueAltGenericSend( QueueHandle_t xQueue, const void * const pvItemToQueue, TickType_t xTicksToWait, BaseType_t xCopyPosition )
	{
	BaseType_t xEntryTimeSet = pdFALSE;
	TimeOut_t xTimeOut;
	Queue_t * const pxQueue = ( Queue_t * ) xQueue;

		configASSERT( pxQueue );
		configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );

		for( ;; )
		{
			taskENTER_CRITICAL(&pxQueue->mux);
			{
				/* Is there room on the queue now?  To be running we must be
				the highest priority task wanting to access the queue. */
				if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
				{
					traceQUEUE_SEND( pxQueue );
					prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );

					/* If there was a task waiting for data to arrive on the
					queue then unblock it now. */
					if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
					{
						if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) == pdTRUE )
						{
							/* The unblocked task has a priority higher than
							our own so yield immediately. */
							taskEXIT_CRITICAL(&pxQueue->mux);
							portYIELD_WITHIN_API();
							taskENTER_CRITICAL(&pxQueue->mux);
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}

					taskEXIT_CRITICAL(&pxQueue->mux);
					return pdPASS;
				}
				else
				{
					if( xTicksToWait == ( TickType_t ) 0 )
					{
						taskEXIT_CRITICAL(&pxQueue->mux);
						return errQUEUE_FULL;
					}
					else if( xEntryTimeSet == pdFALSE )
					{
						vTaskSetTimeOutState( &xTimeOut );
						xEntryTimeSet = pdTRUE;
					}
				}
			}
			taskEXIT_CRITICAL(&pxQueue->mux);

			taskENTER_CRITICAL(&pxQueue->mux);
			{
				if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
				{
					if( prvIsQueueFull( pxQueue ) != pdFALSE )
					{
						traceBLOCKING_ON_QUEUE_SEND( pxQueue );
						vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );
						taskEXIT_CRITICAL(&pxQueue->mux);
						portYIELD_WITHIN_API();
						taskENTER_CRITICAL(&pxQueue->mux);
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					taskEXIT_CRITICAL(&pxQueue->mux);
					traceQUEUE_SEND_FAILED( pxQueue );
					return errQUEUE_FULL;
				}
			}
			taskEXIT_CRITICAL(&pxQueue->mux);
		}
	}

#endif /* configUSE_ALTERNATIVE_API */
/*-----------------------------------------------------------*/

#if ( configUSE_ALTERNATIVE_API == 1 )

	BaseType_t xQueueAltGenericReceive( QueueHandle_t xQueue, void * const pvBuffer, TickType_t xTicksToWait, BaseType_t xJustPeeking )
	{
	BaseType_t xEntryTimeSet = pdFALSE;
	TimeOut_t xTimeOut;
	int8_t *pcOriginalReadPosition;
	Queue_t * const pxQueue = ( Queue_t * ) xQueue;

		configASSERT( pxQueue );
		configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
		UNTESTED_FUNCTION();
		for( ;; )
		{
			taskENTER_CRITICAL();
			{
				if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
				{
					/* Remember our read position in case we are just peeking. */
					pcOriginalReadPosition = pxQueue->u.pcReadFrom;

					prvCopyDataFromQueue( pxQueue, pvBuffer );

					if( xJustPeeking == pdFALSE )
					{
						traceQUEUE_RECEIVE( pxQueue );

						/* Data is actually being removed (not just peeked). */
						--( pxQueue->uxMessagesWaiting );

						#if ( configUSE_MUTEXES == 1 )
						{
							if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
							{
								/* Record the information required to implement
								priority inheritance should it become necessary. */
								pxQueue->pxMutexHolder = ( int8_t * ) xTaskGetCurrentTaskHandle();
							}
							else
							{
								mtCOVERAGE_TEST_MARKER();
							}
						}
						#endif

						if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
						{
							if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )
							{
								portYIELD_WITHIN_API();
							}
							else
							{
								mtCOVERAGE_TEST_MARKER();
							}
						}
					}
					else
					{
						traceQUEUE_PEEK( pxQueue );

						/* The data is not being removed, so reset our read
						pointer. */
						pxQueue->u.pcReadFrom = pcOriginalReadPosition;

						/* The data is being left in the queue, so see if there are
						any other tasks waiting for the data. */
						if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
						{
							/* Tasks that are removed from the event list will get added to
							the pending ready list as the scheduler is still suspended. */
							if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
							{
								/* The task waiting has a higher priority than this task. */
								portYIELD_WITHIN_API();
							}
							else
							{
								mtCOVERAGE_TEST_MARKER();
							}
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}

					taskEXIT_CRITICAL();
					return pdPASS;
				}
				else
				{
					if( xTicksToWait == ( TickType_t ) 0 )
					{
						taskEXIT_CRITICAL();
						traceQUEUE_RECEIVE_FAILED( pxQueue );
						return errQUEUE_EMPTY;
					}
					else if( xEntryTimeSet == pdFALSE )
					{
						vTaskSetTimeOutState( &xTimeOut );
						xEntryTimeSet = pdTRUE;
					}
				}
			}
			taskEXIT_CRITICAL();

			taskENTER_CRITICAL();
			{
				if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
				{
					if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
					{
						traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );

						#if ( configUSE_MUTEXES == 1 )
						{
							if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
							{
								taskENTER_CRITICAL();
								{
									vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder );
								}
								taskEXIT_CRITICAL();
							}
							else
							{
								mtCOVERAGE_TEST_MARKER();
							}
						}
						#endif

						vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
						portYIELD_WITHIN_API();
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					taskEXIT_CRITICAL();
					traceQUEUE_RECEIVE_FAILED( pxQueue );
					return errQUEUE_EMPTY;
				}
			}
			taskEXIT_CRITICAL();
		}
	}


#endif /* configUSE_ALTERNATIVE_API */
/*-----------------------------------------------------------*/

BaseType_t xQueueGenericSendFromISR( QueueHandle_t xQueue, const void * const pvItemToQueue, BaseType_t * const pxHigherPriorityTaskWoken, const BaseType_t xCopyPosition )
{
BaseType_t xReturn;
UBaseType_t uxSavedInterruptStatus;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( pxQueue );
	configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
	configASSERT( !( ( xCopyPosition == queueOVERWRITE ) && ( pxQueue->uxLength != 1 ) ) );

	/* RTOS ports that support interrupt nesting have the concept of a maximum
	system call (or maximum API call) interrupt priority.  Interrupts that are
	above the maximum system call priority are kept permanently enabled, even
	when the RTOS kernel is in a critical section, but cannot make any calls to
	FreeRTOS API functions.  If configASSERT() is defined in FreeRTOSConfig.h
	then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
	failure if a FreeRTOS API function is called from an interrupt that has been
	assigned a priority above the configured maximum system call priority.
	Only FreeRTOS functions that end in FromISR can be called from interrupts
	that have been assigned a priority at or (logically) below the maximum
	system call	interrupt priority.  FreeRTOS maintains a separate interrupt
	safe API to ensure interrupt entry is as fast and as simple as possible.
	More information (albeit Cortex-M specific) is provided on the following
	link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
	portASSERT_IF_INTERRUPT_PRIORITY_INVALID();

	/* Similar to xQueueGenericSend, except without blocking if there is no room
	in the queue.  Also don't directly wake a task that was blocked on a queue
	read, instead return a flag to say whether a context switch is required or
	not (i.e. has a task with a higher priority than us been woken by this
	post). */
	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
	{
		taskENTER_CRITICAL_ISR(&pxQueue->mux);
		if( ( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) || ( xCopyPosition == queueOVERWRITE ) )
		{
			traceQUEUE_SEND_FROM_ISR( pxQueue );
	
			/* A task can only have an inherited priority if it is a mutex
			holder - and if there is a mutex holder then the mutex cannot be
			given from an ISR.  Therefore, unlike the xQueueGenericGive()
			function, there is no need to determine the need for priority
			disinheritance here or to clear the mutex holder TCB member. */
			( void ) prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );

			#if ( configUSE_QUEUE_SETS == 1 )
			{
				if( pxQueue->pxQueueSetContainer != NULL )
				{
					if( prvNotifyQueueSetContainer( pxQueue, xCopyPosition ) == pdTRUE )
					{
						/* The queue is a member of a queue set, and posting
						to the queue set caused a higher priority task to
						unblock.  A context switch is required. */
						if( pxHigherPriorityTaskWoken != NULL )
						{
							*pxHigherPriorityTaskWoken = pdTRUE;
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
					{
						if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
						{
							/* The task waiting has a higher priority so
							record that a context switch is required. */
							if( pxHigherPriorityTaskWoken != NULL )
							{
								*pxHigherPriorityTaskWoken = pdTRUE;
							}
							else
							{
								mtCOVERAGE_TEST_MARKER();
							}
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
			}
			#else /* configUSE_QUEUE_SETS */
			{
				if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
				{
					if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
					{
						/* The task waiting has a higher priority so record that a
						context	switch is required. */
						if( pxHigherPriorityTaskWoken != NULL )
						{
							*pxHigherPriorityTaskWoken = pdTRUE;
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
			#endif /* configUSE_QUEUE_SETS */
			xReturn = pdPASS;
		}
		else
		{
			traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );
			xReturn = errQUEUE_FULL;
		}
		taskEXIT_CRITICAL_ISR(&pxQueue->mux);
	}
	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );

	return xReturn;
}
/*-----------------------------------------------------------*/

BaseType_t xQueueGiveFromISR( QueueHandle_t xQueue, BaseType_t * const pxHigherPriorityTaskWoken )
{
BaseType_t xReturn;
UBaseType_t uxSavedInterruptStatus;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( pxQueue );

	/* xQueueGenericSendFromISR() should be used in the item size is not 0. */
	configASSERT( pxQueue->uxItemSize == 0 );

	/* RTOS ports that support interrupt nesting have the concept of a maximum
	system call (or maximum API call) interrupt priority.  Interrupts that are
	above the maximum system call priority are kept permanently enabled, even
	when the RTOS kernel is in a critical section, but cannot make any calls to
	FreeRTOS API functions.  If configASSERT() is defined in FreeRTOSConfig.h
	then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
	failure if a FreeRTOS API function is called from an interrupt that has been
	assigned a priority above the configured maximum system call priority.
	Only FreeRTOS functions that end in FromISR can be called from interrupts
	that have been assigned a priority at or (logically) below the maximum
	system call	interrupt priority.  FreeRTOS maintains a separate interrupt
	safe API to ensure interrupt entry is as fast and as simple as possible.
	More information (albeit Cortex-M specific) is provided on the following
	link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
	portASSERT_IF_INTERRUPT_PRIORITY_INVALID();

	/* Similar to xQueueGenericSendFromISR() but used with semaphores where the
	item size is 0.  Don't directly wake a task that was blocked on a queue
	read, instead return a flag to say whether a context switch is required or
	not (i.e. has a task with a higher priority than us been woken by this
	post). */
	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
	{
		taskENTER_CRITICAL_ISR(&pxQueue->mux);
		/* When the queue is used to implement a semaphore no data is ever
		moved through the queue but it is still valid to see if the queue 'has
		space'. */
		if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
		{
			traceQUEUE_SEND_FROM_ISR( pxQueue );

			/* A task can only have an inherited priority if it is a mutex
			holder - and if there is a mutex holder then the mutex cannot be
			given from an ISR.  Therefore, unlike the xQueueGenericGive()
			function, there is no need to determine the need for priority
			disinheritance here or to clear the mutex holder TCB member. */

			++( pxQueue->uxMessagesWaiting );

			#if ( configUSE_QUEUE_SETS == 1 )
			{
				if( pxQueue->pxQueueSetContainer != NULL )
				{
					if( prvNotifyQueueSetContainer( pxQueue, queueSEND_TO_BACK ) == pdTRUE )
					{
						/* The semaphore is a member of a queue set, and
						posting	to the queue set caused a higher priority
						task to	unblock.  A context switch is required. */
						if( pxHigherPriorityTaskWoken != NULL )
						{
							*pxHigherPriorityTaskWoken = pdTRUE;
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
					{
						if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
						{
							/* The task waiting has a higher priority so
							record that a context switch is required. */
							if( pxHigherPriorityTaskWoken != NULL )
							{
								*pxHigherPriorityTaskWoken = pdTRUE;
							}
							else
							{
								mtCOVERAGE_TEST_MARKER();
							}
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
			}
			#else /* configUSE_QUEUE_SETS */
			{
				if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
				{
					if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
					{
						/* The task waiting has a higher priority so record that a
						context	switch is required. */
						if( pxHigherPriorityTaskWoken != NULL )
						{
							*pxHigherPriorityTaskWoken = pdTRUE;
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
			#endif /* configUSE_QUEUE_SETS */

			xReturn = pdPASS;
		}
		else
		{
			traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );
			xReturn = errQUEUE_FULL;
		}
		taskEXIT_CRITICAL_ISR(&pxQueue->mux);
	}
	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );

	return xReturn;
}
/*-----------------------------------------------------------*/

BaseType_t xQueueGenericReceive( QueueHandle_t xQueue, void * const pvBuffer, TickType_t xTicksToWait, const BaseType_t xJustPeeking )
{
BaseType_t xEntryTimeSet = pdFALSE;
TimeOut_t xTimeOut;
int8_t *pcOriginalReadPosition;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( pxQueue );
	configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
	#if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) || ( configUSE_TIMERS == 1 ) )
	{
		configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
	}
	#endif

	/* This function relaxes the coding standard somewhat to allow return
	statements within the function itself.  This is done in the interest
	of execution time efficiency. */

	for( ;; )
	{
		taskENTER_CRITICAL(&pxQueue->mux);
		{
			/* Is there data in the queue now?  To be running the calling task
			must be	the highest priority task wanting to access the queue. */
			if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
			{
				/* Remember the read position in case the queue is only being
				peeked. */
				pcOriginalReadPosition = pxQueue->u.pcReadFrom;

				prvCopyDataFromQueue( pxQueue, pvBuffer );

				if( xJustPeeking == pdFALSE )
				{
					traceQUEUE_RECEIVE( pxQueue );

					/* Actually removing data, not just peeking. */
					--( pxQueue->uxMessagesWaiting );

					#if ( configUSE_MUTEXES == 1 )
					{
						if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
						{
							/* Record the information required to implement
							priority inheritance should it become necessary. */
							pxQueue->pxMutexHolder = ( int8_t * ) pvTaskIncrementMutexHeldCount(); /*lint !e961 Cast is not redundant as TaskHandle_t is a typedef. */
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					#endif /* configUSE_MUTEXES */

					if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
					{
						if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) == pdTRUE )
						{
							queueYIELD_IF_USING_PREEMPTION_MUX(&pxQueue->mux);
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					traceQUEUE_PEEK( pxQueue );

					/* The data is not being removed, so reset the read
					pointer. */
					pxQueue->u.pcReadFrom = pcOriginalReadPosition;

					/* The data is being left in the queue, so see if there are
					any other tasks waiting for the data. */
					if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
					{
						/* Tasks that are removed from the event list will get added to
						the pending ready list as the scheduler is still suspended. */
						if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
						{
							/* The task waiting has a higher priority than this task. */
							queueYIELD_IF_USING_PREEMPTION_MUX(&pxQueue->mux);
						}
						else
						{
							mtCOVERAGE_TEST_MARKER();
						}
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}

				taskEXIT_CRITICAL(&pxQueue->mux);
				return pdPASS;
			}
			else
			{
				if( xTicksToWait == ( TickType_t ) 0 )
				{
					/* The queue was empty and no block time is specified (or
					the block time has expired) so leave now. */
					traceQUEUE_RECEIVE_FAILED( pxQueue );
					taskEXIT_CRITICAL(&pxQueue->mux);
					return errQUEUE_EMPTY;
				}
				else if( xEntryTimeSet == pdFALSE )
				{
					/* The queue was empty and a block time was specified so
					configure the timeout structure. */
					vTaskSetTimeOutState( &xTimeOut );
					xEntryTimeSet = pdTRUE;
				}
				else
				{
					/* Entry time was already set. */
					mtCOVERAGE_TEST_MARKER();
				}
			}
		}
		taskEXIT_CRITICAL(&pxQueue->mux);

		/* Interrupts and other tasks can send to and receive from the queue
		now the critical section has been exited. */

		taskENTER_CRITICAL(&pxQueue->mux);

		/* Update the timeout state to see if it has expired yet. */
		if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
		{
			if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
			{
				traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );

				#if ( configUSE_MUTEXES == 1 )
				{
					if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
					{
						vTaskPriorityInherit( ( void * ) pxQueue->pxMutexHolder );
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				#endif

				vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
				taskEXIT_CRITICAL(&pxQueue->mux);
				portYIELD_WITHIN_API();
			}
			else
			{
				/* Try again. */
				taskEXIT_CRITICAL(&pxQueue->mux);
			}
		}
		else
		{
			taskEXIT_CRITICAL(&pxQueue->mux);
			traceQUEUE_RECEIVE_FAILED( pxQueue );
			return errQUEUE_EMPTY;
		}
	}
}
/*-----------------------------------------------------------*/

BaseType_t xQueueReceiveFromISR( QueueHandle_t xQueue, void * const pvBuffer, BaseType_t * const pxHigherPriorityTaskWoken )
{
BaseType_t xReturn;
UBaseType_t uxSavedInterruptStatus;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( pxQueue );
	configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );

	/* RTOS ports that support interrupt nesting have the concept of a maximum
	system call (or maximum API call) interrupt priority.  Interrupts that are
	above the maximum system call priority are kept permanently enabled, even
	when the RTOS kernel is in a critical section, but cannot make any calls to
	FreeRTOS API functions.  If configASSERT() is defined in FreeRTOSConfig.h
	then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
	failure if a FreeRTOS API function is called from an interrupt that has been
	assigned a priority above the configured maximum system call priority.
	Only FreeRTOS functions that end in FromISR can be called from interrupts
	that have been assigned a priority at or (logically) below the maximum
	system call	interrupt priority.  FreeRTOS maintains a separate interrupt
	safe API to ensure interrupt entry is as fast and as simple as possible.
	More information (albeit Cortex-M specific) is provided on the following
	link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
	portASSERT_IF_INTERRUPT_PRIORITY_INVALID();

	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
	{
		taskENTER_CRITICAL_ISR(&pxQueue->mux);
		/* Cannot block in an ISR, so check there is data available. */
		if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
		{
			traceQUEUE_RECEIVE_FROM_ISR( pxQueue );

			prvCopyDataFromQueue( pxQueue, pvBuffer );
			--( pxQueue->uxMessagesWaiting );

			if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
			{
				if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
				{
					/* The task waiting has a higher priority than us so
					force a context switch. */
					if( pxHigherPriorityTaskWoken != NULL )
					{
						*pxHigherPriorityTaskWoken = pdTRUE;
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}

			xReturn = pdPASS;
		}
		else
		{
			xReturn = pdFAIL;
			traceQUEUE_RECEIVE_FROM_ISR_FAILED( pxQueue );
		}
		taskEXIT_CRITICAL_ISR(&pxQueue->mux);
	}
	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );

	return xReturn;
}
/*-----------------------------------------------------------*/

BaseType_t xQueuePeekFromISR( QueueHandle_t xQueue,  void * const pvBuffer )
{
BaseType_t xReturn;
UBaseType_t uxSavedInterruptStatus;
int8_t *pcOriginalReadPosition;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( pxQueue );
	configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
	configASSERT( pxQueue->uxItemSize != 0 ); /* Can't peek a semaphore. */

	/* RTOS ports that support interrupt nesting have the concept of a maximum
	system call (or maximum API call) interrupt priority.  Interrupts that are
	above the maximum system call priority are kept permanently enabled, even
	when the RTOS kernel is in a critical section, but cannot make any calls to
	FreeRTOS API functions.  If configASSERT() is defined in FreeRTOSConfig.h
	then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
	failure if a FreeRTOS API function is called from an interrupt that has been
	assigned a priority above the configured maximum system call priority.
	Only FreeRTOS functions that end in FromISR can be called from interrupts
	that have been assigned a priority at or (logically) below the maximum
	system call	interrupt priority.  FreeRTOS maintains a separate interrupt
	safe API to ensure interrupt entry is as fast and as simple as possible.
	More information (albeit Cortex-M specific) is provided on the following
	link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
	portASSERT_IF_INTERRUPT_PRIORITY_INVALID();

	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
	taskENTER_CRITICAL_ISR(&pxQueue->mux);
	{
		/* Cannot block in an ISR, so check there is data available. */
		if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
		{
			traceQUEUE_PEEK_FROM_ISR( pxQueue );

			/* Remember the read position so it can be reset as nothing is
			actually being removed from the queue. */
			pcOriginalReadPosition = pxQueue->u.pcReadFrom;
			prvCopyDataFromQueue( pxQueue, pvBuffer );
			pxQueue->u.pcReadFrom = pcOriginalReadPosition;

			xReturn = pdPASS;
		}
		else
		{
			xReturn = pdFAIL;
			traceQUEUE_PEEK_FROM_ISR_FAILED( pxQueue );
		}
	}
	taskEXIT_CRITICAL_ISR(&pxQueue->mux);
	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );

	return xReturn;
}
/*-----------------------------------------------------------*/

UBaseType_t uxQueueMessagesWaiting( const QueueHandle_t xQueue )
{
UBaseType_t uxReturn;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( xQueue );

	taskENTER_CRITICAL(&pxQueue->mux);
	{
		uxReturn = ( ( Queue_t * ) xQueue )->uxMessagesWaiting;
	}
	taskEXIT_CRITICAL(&pxQueue->mux);

	return uxReturn;
} /*lint !e818 Pointer cannot be declared const as xQueue is a typedef not pointer. */
/*-----------------------------------------------------------*/

UBaseType_t uxQueueSpacesAvailable( const QueueHandle_t xQueue )
{
UBaseType_t uxReturn;
Queue_t *pxQueue;

	pxQueue = ( Queue_t * ) xQueue;
	configASSERT( pxQueue );

	taskENTER_CRITICAL(&pxQueue->mux);
	{
		uxReturn = pxQueue->uxLength - pxQueue->uxMessagesWaiting;
	}
	taskEXIT_CRITICAL(&pxQueue->mux);

	return uxReturn;
} /*lint !e818 Pointer cannot be declared const as xQueue is a typedef not pointer. */
/*-----------------------------------------------------------*/

UBaseType_t uxQueueMessagesWaitingFromISR( const QueueHandle_t xQueue )
{
UBaseType_t uxReturn;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( xQueue );

	taskENTER_CRITICAL_ISR(&pxQueue->mux);
	uxReturn = ( ( Queue_t * ) xQueue )->uxMessagesWaiting;
	taskEXIT_CRITICAL_ISR(&pxQueue->mux);

	return uxReturn;
} /*lint !e818 Pointer cannot be declared const as xQueue is a typedef not pointer. */
/*-----------------------------------------------------------*/

void vQueueDelete( QueueHandle_t xQueue )
{
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( pxQueue );

	traceQUEUE_DELETE( pxQueue );
	#if ( configQUEUE_REGISTRY_SIZE > 0 )
	{
		vQueueUnregisterQueue( pxQueue );
	}
	#endif

	#if( ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 0 ) )
	{
		/* The queue can only have been allocated dynamically - free it
		again. */
		vPortFree( pxQueue );
	}
	#elif( ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
	{
		/* The queue could have been allocated statically or dynamically, so
		check before attempting to free the memory. */
		if( pxQueue->ucStaticallyAllocated == ( uint8_t ) pdFALSE )
		{
			vPortFree( pxQueue );
		}
		else
		{
			mtCOVERAGE_TEST_MARKER();
		}
	}
	#else
	{
		/* The queue must have been statically allocated, so is not going to be
		deleted.  Avoid compiler warnings about the unused parameter. */
		( void ) pxQueue;
	}
	#endif /* configSUPPORT_DYNAMIC_ALLOCATION */
}
/*-----------------------------------------------------------*/

#if ( configUSE_TRACE_FACILITY == 1 )

	UBaseType_t uxQueueGetQueueNumber( QueueHandle_t xQueue )
	{
		return ( ( Queue_t * ) xQueue )->uxQueueNumber;
	}

#endif /* configUSE_TRACE_FACILITY */
/*-----------------------------------------------------------*/

#if ( configUSE_TRACE_FACILITY == 1 )

	void vQueueSetQueueNumber( QueueHandle_t xQueue, UBaseType_t uxQueueNumber )
	{
		( ( Queue_t * ) xQueue )->uxQueueNumber = uxQueueNumber;
	}

#endif /* configUSE_TRACE_FACILITY */
/*-----------------------------------------------------------*/

#if ( configUSE_TRACE_FACILITY == 1 )

	uint8_t ucQueueGetQueueType( QueueHandle_t xQueue )
	{
		return ( ( Queue_t * ) xQueue )->ucQueueType;
	}

#endif /* configUSE_TRACE_FACILITY */
/*-----------------------------------------------------------*/

//This routine assumes the queue has already been locked.
static BaseType_t prvCopyDataToQueue( Queue_t * const pxQueue, const void *pvItemToQueue, const BaseType_t xPosition )
{
BaseType_t xReturn = pdFALSE;

	if( pxQueue->uxItemSize == ( UBaseType_t ) 0 )
	{
		#if ( configUSE_MUTEXES == 1 )
		{
			if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
			{
				/* The mutex is no longer being held. */
				xReturn = xTaskPriorityDisinherit( ( void * ) pxQueue->pxMutexHolder );
				pxQueue->pxMutexHolder = NULL;
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}
		}
		#endif /* configUSE_MUTEXES */
	}
	else if( xPosition == queueSEND_TO_BACK )
	{
		( void ) memcpy( ( void * ) pxQueue->pcWriteTo, pvItemToQueue, ( size_t ) pxQueue->uxItemSize ); /*lint !e961 !e418 MISRA exception as the casts are only redundant for some ports, plus previous logic ensures a null pointer can only be passed to memcpy() if the copy size is 0. */
		pxQueue->pcWriteTo += pxQueue->uxItemSize;
		if( pxQueue->pcWriteTo >= pxQueue->pcTail ) /*lint !e946 MISRA exception justified as comparison of pointers is the cleanest solution. */
		{
			pxQueue->pcWriteTo = pxQueue->pcHead;
		}
		else
		{
			mtCOVERAGE_TEST_MARKER();
		}
	}
	else
	{
		( void ) memcpy( ( void * ) pxQueue->u.pcReadFrom, pvItemToQueue, ( size_t ) pxQueue->uxItemSize ); /*lint !e961 MISRA exception as the casts are only redundant for some ports. */
		pxQueue->u.pcReadFrom -= pxQueue->uxItemSize;
		if( pxQueue->u.pcReadFrom < pxQueue->pcHead ) /*lint !e946 MISRA exception justified as comparison of pointers is the cleanest solution. */
		{
			pxQueue->u.pcReadFrom = ( pxQueue->pcTail - pxQueue->uxItemSize );
		}
		else
		{
			mtCOVERAGE_TEST_MARKER();
		}

		if( xPosition == queueOVERWRITE )
		{
			if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
			{
				/* An item is not being added but overwritten, so subtract
				one from the recorded number of items in the queue so when
				one is added again below the number of recorded items remains
				correct. */
				--( pxQueue->uxMessagesWaiting );
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}
		}
		else
		{
			mtCOVERAGE_TEST_MARKER();
		}
	}

	++( pxQueue->uxMessagesWaiting );

	return xReturn;
}
/*-----------------------------------------------------------*/

static void prvCopyDataFromQueue( Queue_t * const pxQueue, void * const pvBuffer )
{
	if( pxQueue->uxItemSize != ( UBaseType_t ) 0 )
	{
		pxQueue->u.pcReadFrom += pxQueue->uxItemSize;
		if( pxQueue->u.pcReadFrom >= pxQueue->pcTail ) /*lint !e946 MISRA exception justified as use of the relational operator is the cleanest solutions. */
		{
			pxQueue->u.pcReadFrom = pxQueue->pcHead;
		}
		else
		{
			mtCOVERAGE_TEST_MARKER();
		}
		( void ) memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.pcReadFrom, ( size_t ) pxQueue->uxItemSize ); /*lint !e961 !e418 MISRA exception as the casts are only redundant for some ports.  Also previous logic ensures a null pointer can only be passed to memcpy() when the count is 0. */
	}
}

/*-----------------------------------------------------------*/

static BaseType_t prvIsQueueEmpty( Queue_t *pxQueue )
{
BaseType_t xReturn;

	//No lock needed: we read a base type.
	{
		if( pxQueue->uxMessagesWaiting == ( UBaseType_t )  0 )
		{
			xReturn = pdTRUE;
		}
		else
		{
			xReturn = pdFALSE;
		}
	}

	return xReturn;
}
/*-----------------------------------------------------------*/

BaseType_t xQueueIsQueueEmptyFromISR( QueueHandle_t xQueue )
{
BaseType_t xReturn;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( xQueue );
	taskENTER_CRITICAL_ISR(&pxQueue->mux);
	if( ( ( Queue_t * ) xQueue )->uxMessagesWaiting == ( UBaseType_t ) 0 )
	{
		xReturn = pdTRUE;
	}
	else
	{
		xReturn = pdFALSE;
	}
	taskEXIT_CRITICAL_ISR(&pxQueue->mux);

	return xReturn;
} /*lint !e818 xQueue could not be pointer to const because it is a typedef. */
/*-----------------------------------------------------------*/

static BaseType_t prvIsQueueFull( Queue_t *pxQueue )
{
BaseType_t xReturn;

	taskENTER_CRITICAL_ISR(&pxQueue->mux);
	{
		if( pxQueue->uxMessagesWaiting == pxQueue->uxLength )
		{
			xReturn = pdTRUE;
		}
		else
		{
			xReturn = pdFALSE;
		}
	}
	taskEXIT_CRITICAL_ISR(&pxQueue->mux);

	return xReturn;
}
/*-----------------------------------------------------------*/

BaseType_t xQueueIsQueueFullFromISR( QueueHandle_t xQueue )
{
BaseType_t xReturn;
Queue_t * const pxQueue = ( Queue_t * ) xQueue;

	configASSERT( xQueue );
	taskENTER_CRITICAL_ISR(&pxQueue->mux);
	if( ( ( Queue_t * ) xQueue )->uxMessagesWaiting == ( ( Queue_t * ) xQueue )->uxLength )
	{
		xReturn = pdTRUE;
	}
	else
	{
		xReturn = pdFALSE;
	}
	taskEXIT_CRITICAL_ISR(&pxQueue->mux);

	return xReturn;
} /*lint !e818 xQueue could not be pointer to const because it is a typedef. */
/*-----------------------------------------------------------*/

#if ( configUSE_CO_ROUTINES == 1 )

	BaseType_t xQueueCRSend( QueueHandle_t xQueue, const void *pvItemToQueue, TickType_t xTicksToWait )
	{
	BaseType_t xReturn;
	Queue_t * const pxQueue = ( Queue_t * ) xQueue;

		UNTESTED_FUNCTION();
		/* If the queue is already full we may have to block.  A critical section
		is required to prevent an interrupt removing something from the queue
		between the check to see if the queue is full and blocking on the queue. */
		portDISABLE_INTERRUPTS();
		{
			if( prvIsQueueFull( pxQueue ) != pdFALSE )
			{
				/* The queue is full - do we want to block or just leave without
				posting? */
				if( xTicksToWait > ( TickType_t ) 0 )
				{
					/* As this is called from a coroutine we cannot block directly, but
					return indicating that we need to block. */
					vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToSend ) );
					portENABLE_INTERRUPTS();
					return errQUEUE_BLOCKED;
				}
				else
				{
					portENABLE_INTERRUPTS();
					return errQUEUE_FULL;
				}
			}
		}
		portENABLE_INTERRUPTS();

		portDISABLE_INTERRUPTS();
		{
			if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
			{
				/* There is room in the queue, copy the data into the queue. */
				prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );
				xReturn = pdPASS;

				/* Were any co-routines waiting for data to become available? */
				if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
				{
					/* In this instance the co-routine could be placed directly
					into the ready list as we are within a critical section.
					Instead the same pending ready list mechanism is used as if
					the event were caused from within an interrupt. */
					if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
					{
						/* The co-routine waiting has a higher priority so record
						that a yield might be appropriate. */
						xReturn = errQUEUE_YIELD;
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
			else
			{
				xReturn = errQUEUE_FULL;
			}
		}
		portENABLE_INTERRUPTS();

		return xReturn;
	}

#endif /* configUSE_CO_ROUTINES */
/*-----------------------------------------------------------*/

#if ( configUSE_CO_ROUTINES == 1 )

	BaseType_t xQueueCRReceive( QueueHandle_t xQueue, void *pvBuffer, TickType_t xTicksToWait )
	{
	BaseType_t xReturn;
	Queue_t * const pxQueue = ( Queue_t * ) xQueue;

		/* If the queue is already empty we may have to block.  A critical section
		is required to prevent an interrupt adding something to the queue
		between the check to see if the queue is empty and blocking on the queue. */
		portDISABLE_INTERRUPTS();
		{
			if( pxQueue->uxMessagesWaiting == ( UBaseType_t ) 0 )
			{
				/* There are no messages in the queue, do we want to block or just
				leave with nothing? */
				if( xTicksToWait > ( TickType_t ) 0 )
				{
					/* As this is a co-routine we cannot block directly, but return
					indicating that we need to block. */
					vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToReceive ) );
					portENABLE_INTERRUPTS();
					return errQUEUE_BLOCKED;
				}
				else
				{
					portENABLE_INTERRUPTS();
					return errQUEUE_FULL;
				}
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}
		}
		portENABLE_INTERRUPTS();

		portDISABLE_INTERRUPTS();
		{
			if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
			{
				/* Data is available from the queue. */
				pxQueue->u.pcReadFrom += pxQueue->uxItemSize;
				if( pxQueue->u.pcReadFrom >= pxQueue->pcTail )
				{
					pxQueue->u.pcReadFrom = pxQueue->pcHead;
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
				--( pxQueue->uxMessagesWaiting );
				( void ) memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.pcReadFrom, ( unsigned ) pxQueue->uxItemSize );

				xReturn = pdPASS;

				/* Were any co-routines waiting for space to become available? */
				if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
				{
					/* In this instance the co-routine could be placed directly
					into the ready list as we are within a critical section.
					Instead the same pending ready list mechanism is used as if
					the event were caused from within an interrupt. */
					if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
					{
						xReturn = errQUEUE_YIELD;
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
			else
			{
				xReturn = pdFAIL;
			}
		}
		portENABLE_INTERRUPTS();

		return xReturn;
	}

#endif /* configUSE_CO_ROUTINES */
/*-----------------------------------------------------------*/

#if ( configUSE_CO_ROUTINES == 1 )

	BaseType_t xQueueCRSendFromISR( QueueHandle_t xQueue, const void *pvItemToQueue, BaseType_t xCoRoutinePreviouslyWoken )
	{
	Queue_t * const pxQueue = ( Queue_t * ) xQueue;

		/* Cannot block within an ISR so if there is no space on the queue then
		exit without doing anything. */
		if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
		{
			prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );

			/* We only want to wake one co-routine per ISR, so check that a
			co-routine has not already been woken. */
			if( xCoRoutinePreviouslyWoken == pdFALSE )
			{
				if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
				{
					if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
					{
						return pdTRUE;
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}
		}
		else
		{
			mtCOVERAGE_TEST_MARKER();
		}

		return xCoRoutinePreviouslyWoken;
	}

#endif /* configUSE_CO_ROUTINES */
/*-----------------------------------------------------------*/

#if ( configUSE_CO_ROUTINES == 1 )

	BaseType_t xQueueCRReceiveFromISR( QueueHandle_t xQueue, void *pvBuffer, BaseType_t *pxCoRoutineWoken )
	{
	BaseType_t xReturn;
	Queue_t * const pxQueue = ( Queue_t * ) xQueue;

		/* We cannot block from an ISR, so check there is data available. If
		not then just leave without doing anything. */
		if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
		{
			/* Copy the data from the queue. */
			pxQueue->u.pcReadFrom += pxQueue->uxItemSize;
			if( pxQueue->u.pcReadFrom >= pxQueue->pcTail )
			{
				pxQueue->u.pcReadFrom = pxQueue->pcHead;
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}
			--( pxQueue->uxMessagesWaiting );
			( void ) memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.pcReadFrom, ( unsigned ) pxQueue->uxItemSize );

			if( ( *pxCoRoutineWoken ) == pdFALSE )
			{
				if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
				{
					if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
					{
						*pxCoRoutineWoken = pdTRUE;
					}
					else
					{
						mtCOVERAGE_TEST_MARKER();
					}
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}

			xReturn = pdPASS;
		}
		else
		{
			xReturn = pdFAIL;
		}

		return xReturn;
	}

#endif /* configUSE_CO_ROUTINES */
/*-----------------------------------------------------------*/

#if ( configQUEUE_REGISTRY_SIZE > 0 )

	void vQueueAddToRegistry( QueueHandle_t xQueue, const char *pcQueueName ) /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
	{
	UBaseType_t ux;
		
		UNTESTED_FUNCTION();
		/* See if there is an empty space in the registry.  A NULL name denotes
		a free slot. */
		for( ux = ( UBaseType_t ) 0U; ux < ( UBaseType_t ) configQUEUE_REGISTRY_SIZE; ux++ )
		{
			if( xQueueRegistry[ ux ].pcQueueName == NULL )
			{
				/* Store the information on this queue. */
				xQueueRegistry[ ux ].pcQueueName = pcQueueName;
				xQueueRegistry[ ux ].xHandle = xQueue;

				traceQUEUE_REGISTRY_ADD( xQueue, pcQueueName );
				break;
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}
		}
	}

#endif /* configQUEUE_REGISTRY_SIZE */
/*-----------------------------------------------------------*/

#if ( configQUEUE_REGISTRY_SIZE > 0 )

	void vQueueUnregisterQueue( QueueHandle_t xQueue )
	{
	UBaseType_t ux;

		/* See if the handle of the queue being unregistered in actually in the
		registry. */
		for( ux = ( UBaseType_t ) 0U; ux < ( UBaseType_t ) configQUEUE_REGISTRY_SIZE; ux++ )
		{
			if( xQueueRegistry[ ux ].xHandle == xQueue )
			{
				/* Set the name to NULL to show that this slot if free again. */
				xQueueRegistry[ ux ].pcQueueName = NULL;
				break;
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}
		}

	} /*lint !e818 xQueue could not be pointer to const because it is a typedef. */

#endif /* configQUEUE_REGISTRY_SIZE */
/*-----------------------------------------------------------*/

#if ( configUSE_TIMERS == 1 )

	void vQueueWaitForMessageRestricted( QueueHandle_t xQueue, TickType_t xTicksToWait )
	{
	Queue_t * const pxQueue = ( Queue_t * ) xQueue;

		/* This function should not be called by application code hence the
		'Restricted' in its name.  It is not part of the public API.  It is
		designed for use by kernel code, and has special calling requirements.
		It can result in vListInsert() being called on a list that can only
		possibly ever have one item in it, so the list will be fast, but even
		so it should be called with the scheduler locked and not from a critical
		section. */

		/* Only do anything if there are no messages in the queue.  This function
		will not actually cause the task to block, just place it on a blocked
		list.  It will not block until the scheduler is unlocked - at which
		time a yield will be performed.  */
		taskENTER_CRITICAL(&pxQueue->mux);
		if( pxQueue->uxMessagesWaiting == ( UBaseType_t ) 0U )
		{
			/* There is nothing in the queue, block for the specified period. */
			vTaskPlaceOnEventListRestricted( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
		}
		else
		{
			mtCOVERAGE_TEST_MARKER();
		}
		taskEXIT_CRITICAL(&pxQueue->mux);
	}

#endif /* configUSE_TIMERS */
/*-----------------------------------------------------------*/

#if( ( configUSE_QUEUE_SETS == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )

	QueueSetHandle_t xQueueCreateSet( const UBaseType_t uxEventQueueLength )
	{
	QueueSetHandle_t pxQueue;

		pxQueue = xQueueGenericCreate( uxEventQueueLength, sizeof( Queue_t * ), queueQUEUE_TYPE_SET );

		return pxQueue;
	}

#endif /* configUSE_QUEUE_SETS */
/*-----------------------------------------------------------*/

#if ( configUSE_QUEUE_SETS == 1 )

	BaseType_t xQueueAddToSet( QueueSetMemberHandle_t xQueueOrSemaphore, QueueSetHandle_t xQueueSet )
	{
	BaseType_t xReturn;

//ToDo: figure out locking
//		taskENTER_CRITICAL(&pxQueue->mux);
		{
			if( ( ( Queue_t * ) xQueueOrSemaphore )->pxQueueSetContainer != NULL )
			{
				/* Cannot add a queue/semaphore to more than one queue set. */
				xReturn = pdFAIL;
			}
			else if( ( ( Queue_t * ) xQueueOrSemaphore )->uxMessagesWaiting != ( UBaseType_t ) 0 )
			{
				/* Cannot add a queue/semaphore to a queue set if there are already
				items in the queue/semaphore. */
				xReturn = pdFAIL;
			}
			else
			{
				( ( Queue_t * ) xQueueOrSemaphore )->pxQueueSetContainer = xQueueSet;
				xReturn = pdPASS;
			}
		}
//		taskEXIT_CRITICAL(&pxQueue->mux);

		return xReturn;
	}

#endif /* configUSE_QUEUE_SETS */
/*-----------------------------------------------------------*/

#if ( configUSE_QUEUE_SETS == 1 )

	BaseType_t xQueueRemoveFromSet( QueueSetMemberHandle_t xQueueOrSemaphore, QueueSetHandle_t xQueueSet )
	{
	BaseType_t xReturn;
	Queue_t * const pxQueueOrSemaphore = ( Queue_t * ) xQueueOrSemaphore;

		if( pxQueueOrSemaphore->pxQueueSetContainer != xQueueSet )
		{
			/* The queue was not a member of the set. */
			xReturn = pdFAIL;
		}
		else if( pxQueueOrSemaphore->uxMessagesWaiting != ( UBaseType_t ) 0 )
		{
			/* It is dangerous to remove a queue from a set when the queue is
			not empty because the queue set will still hold pending events for
			the queue. */
			xReturn = pdFAIL;
		}
		else
		{
//			taskENTER_CRITICAL(&pxQueue->mux);
			{
				/* The queue is no longer contained in the set. */
				pxQueueOrSemaphore->pxQueueSetContainer = NULL;
			}
//			taskEXIT_CRITICAL(&pxQueue->mux);
			xReturn = pdPASS;
		}

		return xReturn;
	} /*lint !e818 xQueueSet could not be declared as pointing to const as it is a typedef. */

#endif /* configUSE_QUEUE_SETS */
/*-----------------------------------------------------------*/

#if ( configUSE_QUEUE_SETS == 1 )

	QueueSetMemberHandle_t xQueueSelectFromSet( QueueSetHandle_t xQueueSet, TickType_t const xTicksToWait )
	{
	QueueSetMemberHandle_t xReturn = NULL;

		( void ) xQueueGenericReceive( ( QueueHandle_t ) xQueueSet, &xReturn, xTicksToWait, pdFALSE ); /*lint !e961 Casting from one typedef to another is not redundant. */
		return xReturn;
	}

#endif /* configUSE_QUEUE_SETS */
/*-----------------------------------------------------------*/

#if ( configUSE_QUEUE_SETS == 1 )

	QueueSetMemberHandle_t xQueueSelectFromSetFromISR( QueueSetHandle_t xQueueSet )
	{
	QueueSetMemberHandle_t xReturn = NULL;

		( void ) xQueueReceiveFromISR( ( QueueHandle_t ) xQueueSet, &xReturn, NULL ); /*lint !e961 Casting from one typedef to another is not redundant. */
		return xReturn;
	}

#endif /* configUSE_QUEUE_SETS */
/*-----------------------------------------------------------*/

#if ( configUSE_QUEUE_SETS == 1 )

	static BaseType_t prvNotifyQueueSetContainer( const Queue_t * const pxQueue, const BaseType_t xCopyPosition )
	{
	Queue_t *pxQueueSetContainer = pxQueue->pxQueueSetContainer;
	BaseType_t xReturn = pdFALSE;

		/* This function must be called form a critical section. */

		configASSERT( pxQueueSetContainer );
		configASSERT( pxQueueSetContainer->uxMessagesWaiting < pxQueueSetContainer->uxLength );

		if( pxQueueSetContainer->uxMessagesWaiting < pxQueueSetContainer->uxLength )
		{
			traceQUEUE_SEND( pxQueueSetContainer );
			/* The data copied is the handle of the queue that contains data. */
			xReturn = prvCopyDataToQueue( pxQueueSetContainer, &pxQueue, xCopyPosition );

			if( listLIST_IS_EMPTY( &( pxQueueSetContainer->xTasksWaitingToReceive ) ) == pdFALSE )
			{
				if( xTaskRemoveFromEventList( &( pxQueueSetContainer->xTasksWaitingToReceive ) ) != pdFALSE )
				{
					/* The task waiting has a higher priority */
					xReturn = pdTRUE;
				}
				else
				{
					mtCOVERAGE_TEST_MARKER();
				}
			}
			else
			{
				mtCOVERAGE_TEST_MARKER();
			}
		}
		else
		{
			mtCOVERAGE_TEST_MARKER();
		}

		return xReturn;
	}

#endif /* configUSE_QUEUE_SETS */