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queue.c

Last change on this file was 73, checked in by Zed, 3 months ago
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1	/*
2	* FreeRTOS Kernel V10.3.1
3	* Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
4	*
5	* Permission is hereby granted, free of charge, to any person obtaining a copy of
6	* this software and associated documentation files (the "Software"), to deal in
7	* the Software without restriction, including without limitation the rights to
8	* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
9	* the Software, and to permit persons to whom the Software is furnished to do so,
10	* subject to the following conditions:
11	*
12	* The above copyright notice and this permission notice shall be included in all
13	* copies or substantial portions of the Software.
14	*
15	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
17	* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
18	* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
19	* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
20	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
21	*
22	* http://www.FreeRTOS.org
23	* http://aws.amazon.com/freertos
24	*
25	* 1 tab == 4 spaces!
26	*/
27
28	#include <stdlib.h>
29	#include <string.h>
30
31	/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining
32	all the API functions to use the MPU wrappers. That should only be done when
33	task.h is included from an application file. */
34	#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
35
36	#include "FreeRTOS.h"
37	#include "task.h"
38	#include "queue.h"
39
40	#if ( configUSE_CO_ROUTINES == 1 )
41	#include "croutine.h"
42	#endif
43
44	/* Lint e9021, e961 and e750 are suppressed as a MISRA exception justified
45	because the MPU ports require MPU_WRAPPERS_INCLUDED_FROM_API_FILE to be defined
46	for the header files above, but not in this file, in order to generate the
47	correct privileged Vs unprivileged linkage and placement. */
48	#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /lint !e961 !e750 !e9021. /
49
50
51	/* Constants used with the cRxLock and cTxLock structure members. */
52	#define queueUNLOCKED ( ( int8_t ) -1 )
53	#define queueLOCKED_UNMODIFIED ( ( int8_t ) 0 )
54
55	/* When the Queue_t structure is used to represent a base queue its pcHead and
56	pcTail members are used as pointers into the queue storage area. When the
57	Queue_t structure is used to represent a mutex pcHead and pcTail pointers are
58	not necessary, and the pcHead pointer is set to NULL to indicate that the
59	structure instead holds a pointer to the mutex holder (if any). Map alternative
60	names to the pcHead and structure member to ensure the readability of the code
61	is maintained. The QueuePointers_t and SemaphoreData_t types are used to form
62	a union as their usage is mutually exclusive dependent on what the queue is
63	being used for. */
64	#define uxQueueType pcHead
65	#define queueQUEUE_IS_MUTEX NULL
66
67	typedef struct QueuePointers
68	{
69	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. */
70	int8_t pcReadFrom; /< Points to the last place that a queued item was read from when the structure is used as a queue. */
71	} QueuePointers_t;
72
73	typedef struct SemaphoreData
74	{
75	TaskHandle_t xMutexHolder; /< The handle of the task that holds the mutex. /
76	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. /
77	} SemaphoreData_t;
78
79	/* Semaphores do not actually store or copy data, so have an item size of
80	zero. */
81	#define queueSEMAPHORE_QUEUE_ITEM_LENGTH ( ( UBaseType_t ) 0 )
82	#define queueMUTEX_GIVE_BLOCK_TIME ( ( TickType_t ) 0U )
83
84	#if( configUSE_PREEMPTION == 0 )
85	/* If the cooperative scheduler is being used then a yield should not be
86	performed just because a higher priority task has been woken. */
87	#define queueYIELD_IF_USING_PREEMPTION()
88	#else
89	#define queueYIELD_IF_USING_PREEMPTION() portYIELD_WITHIN_API()
90	#endif
91
92	/*
93	* Definition of the queue used by the scheduler.
94	* Items are queued by copy, not reference. See the following link for the
95	* rationale: https://www.freertos.org/Embedded-RTOS-Queues.html
96	*/
97	typedef struct QueueDefinition /* The old naming convention is used to prevent breaking kernel aware debuggers. */
98	{
99	int8_t pcHead; /< Points to the beginning of the queue storage area. */
100	int8_t pcWriteTo; /< Points to the free next place in the storage area. */
101
102	union
103	{
104	QueuePointers_t xQueue; /< Data required exclusively when this structure is used as a queue. /
105	SemaphoreData_t xSemaphore; /< Data required exclusively when this structure is used as a semaphore. /
106	} u;
107
108	List_t xTasksWaitingToSend; /< List of tasks that are blocked waiting to post onto this queue. Stored in priority order. /
109	List_t xTasksWaitingToReceive; /< List of tasks that are blocked waiting to read from this queue. Stored in priority order. /
110
111	volatile UBaseType_t uxMessagesWaiting;/< The number of items currently in the queue. /
112	UBaseType_t uxLength; /< The length of the queue defined as the number of items it will hold, not the number of bytes. /
113	UBaseType_t uxItemSize; /< The size of each items that the queue will hold. /
114
115	volatile int8_t cRxLock; /< Stores the number of items received from the queue (removed from the queue) while the queue was locked. Set to queueUNLOCKED when the queue is not locked. /
116	volatile int8_t cTxLock; /< Stores the number of items transmitted to the queue (added to the queue) while the queue was locked. Set to queueUNLOCKED when the queue is not locked. /
117
118	#if( ( configSUPPORT_STATIC_ALLOCATION == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
119	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. /
120	#endif
121
122	#if ( configUSE_QUEUE_SETS == 1 )
123	struct QueueDefinition *pxQueueSetContainer;
124	#endif
125
126	#if ( configUSE_TRACE_FACILITY == 1 )
127	UBaseType_t uxQueueNumber;
128	uint8_t ucQueueType;
129	#endif
130
131	} xQUEUE;
132
133	/* The old xQUEUE name is maintained above then typedefed to the new Queue_t
134	name below to enable the use of older kernel aware debuggers. */
135	typedef xQUEUE Queue_t;
136
137	/-----------------------------------------------------------/
138
139	/*
140	* The queue registry is just a means for kernel aware debuggers to locate
141	* queue structures. It has no other purpose so is an optional component.
142	*/
143	#if ( configQUEUE_REGISTRY_SIZE > 0 )
144
145	/* The type stored within the queue registry array. This allows a name
146	to be assigned to each queue making kernel aware debugging a little
147	more user friendly. */
148	typedef struct QUEUE_REGISTRY_ITEM
149	{
150	const char pcQueueName; /lint !e971 Unqualified char types are allowed for strings and single characters only. */
151	QueueHandle_t xHandle;
152	} xQueueRegistryItem;
153
154	/* The old xQueueRegistryItem name is maintained above then typedefed to the
155	new xQueueRegistryItem name below to enable the use of older kernel aware
156	debuggers. */
157	typedef xQueueRegistryItem QueueRegistryItem_t;
158
159	/* The queue registry is simply an array of QueueRegistryItem_t structures.
160	The pcQueueName member of a structure being NULL is indicative of the
161	array position being vacant. */
162	PRIVILEGED_DATA QueueRegistryItem_t xQueueRegistry[ configQUEUE_REGISTRY_SIZE ];
163
164	#endif /* configQUEUE_REGISTRY_SIZE */
165
166	/*
167	* Unlocks a queue locked by a call to prvLockQueue. Locking a queue does not
168	* prevent an ISR from adding or removing items to the queue, but does prevent
169	* an ISR from removing tasks from the queue event lists. If an ISR finds a
170	* queue is locked it will instead increment the appropriate queue lock count
171	* to indicate that a task may require unblocking. When the queue in unlocked
172	* these lock counts are inspected, and the appropriate action taken.
173	*/
174	static void prvUnlockQueue( Queue_t * const pxQueue ) PRIVILEGED_FUNCTION;
175
176	/*
177	* Uses a critical section to determine if there is any data in a queue.
178	*
179	* @return pdTRUE if the queue contains no items, otherwise pdFALSE.
180	*/
181	static BaseType_t prvIsQueueEmpty( const Queue_t *pxQueue ) PRIVILEGED_FUNCTION;
182
183	/*
184	* Uses a critical section to determine if there is any space in a queue.
185	*
186	* @return pdTRUE if there is no space, otherwise pdFALSE;
187	*/
188	static BaseType_t prvIsQueueFull( const Queue_t *pxQueue ) PRIVILEGED_FUNCTION;
189
190	/*
191	* Copies an item into the queue, either at the front of the queue or the
192	* back of the queue.
193	*/
194	static BaseType_t prvCopyDataToQueue( Queue_t * const pxQueue, const void *pvItemToQueue, const BaseType_t xPosition ) PRIVILEGED_FUNCTION;
195
196	/*
197	* Copies an item out of a queue.
198	*/
199	static void prvCopyDataFromQueue( Queue_t * const pxQueue, void * const pvBuffer ) PRIVILEGED_FUNCTION;
200
201	#if ( configUSE_QUEUE_SETS == 1 )
202	/*
203	* Checks to see if a queue is a member of a queue set, and if so, notifies
204	* the queue set that the queue contains data.
205	*/
206	static BaseType_t prvNotifyQueueSetContainer( const Queue_t * const pxQueue ) PRIVILEGED_FUNCTION;
207	#endif
208
209	/*
210	* Called after a Queue_t structure has been allocated either statically or
211	* dynamically to fill in the structure's members.
212	*/
213	static void prvInitialiseNewQueue( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, uint8_t pucQueueStorage, const uint8_t ucQueueType, Queue_t pxNewQueue ) PRIVILEGED_FUNCTION;
214
215	/*
216	* Mutexes are a special type of queue. When a mutex is created, first the
217	* queue is created, then prvInitialiseMutex() is called to configure the queue
218	* as a mutex.
219	*/
220	#if( configUSE_MUTEXES == 1 )
221	static void prvInitialiseMutex( Queue_t *pxNewQueue ) PRIVILEGED_FUNCTION;
222	#endif
223
224	#if( configUSE_MUTEXES == 1 )
225	/*
226	* If a task waiting for a mutex causes the mutex holder to inherit a
227	* priority, but the waiting task times out, then the holder should
228	* disinherit the priority - but only down to the highest priority of any
229	* other tasks that are waiting for the same mutex. This function returns
230	* that priority.
231	*/
232	static UBaseType_t prvGetDisinheritPriorityAfterTimeout( const Queue_t * const pxQueue ) PRIVILEGED_FUNCTION;
233	#endif
234	/-----------------------------------------------------------/
235
236	/*
237	* Macro to mark a queue as locked. Locking a queue prevents an ISR from
238	* accessing the queue event lists.
239	*/
240	#define prvLockQueue( pxQueue ) \
241	taskENTER_CRITICAL(); \
242	{ \
243	if( ( pxQueue )->cRxLock == queueUNLOCKED ) \
244	{ \
245	( pxQueue )->cRxLock = queueLOCKED_UNMODIFIED; \
246	} \
247	if( ( pxQueue )->cTxLock == queueUNLOCKED ) \
248	{ \
249	( pxQueue )->cTxLock = queueLOCKED_UNMODIFIED; \
250	} \
251	} \
252	taskEXIT_CRITICAL()
253	/-----------------------------------------------------------/
254
255	BaseType_t xQueueGenericReset( QueueHandle_t xQueue, BaseType_t xNewQueue )
256	{
257	Queue_t * const pxQueue = xQueue;
258
259	configASSERT( pxQueue );
260
261	taskENTER_CRITICAL();
262	{
263	pxQueue->u.xQueue.pcTail = pxQueue->pcHead + ( pxQueue->uxLength * pxQueue->uxItemSize ); /lint !e9016 Pointer arithmetic allowed on char types, especially when it assists conveying intent. /
264	pxQueue->uxMessagesWaiting = ( UBaseType_t ) 0U;
265	pxQueue->pcWriteTo = pxQueue->pcHead;
266	pxQueue->u.xQueue.pcReadFrom = pxQueue->pcHead + ( ( pxQueue->uxLength - 1U ) * pxQueue->uxItemSize ); /lint !e9016 Pointer arithmetic allowed on char types, especially when it assists conveying intent. /
267	pxQueue->cRxLock = queueUNLOCKED;
268	pxQueue->cTxLock = queueUNLOCKED;
269
270	if( xNewQueue == pdFALSE )
271	{
272	/* If there are tasks blocked waiting to read from the queue, then
273	the tasks will remain blocked as after this function exits the queue
274	will still be empty. If there are tasks blocked waiting to write to
275	the queue, then one should be unblocked as after this function exits
276	it will be possible to write to it. */
277	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
278	{
279	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
280	{
281	queueYIELD_IF_USING_PREEMPTION();
282	}
283	else
284	{
285	mtCOVERAGE_TEST_MARKER();
286	}
287	}
288	else
289	{
290	mtCOVERAGE_TEST_MARKER();
291	}
292	}
293	else
294	{
295	/* Ensure the event queues start in the correct state. */
296	vListInitialise( &( pxQueue->xTasksWaitingToSend ) );
297	vListInitialise( &( pxQueue->xTasksWaitingToReceive ) );
298	}
299	}
300	taskEXIT_CRITICAL();
301
302	/* A value is returned for calling semantic consistency with previous
303	versions. */
304	return pdPASS;
305	}
306	/-----------------------------------------------------------/
307
308	#if( configSUPPORT_STATIC_ALLOCATION == 1 )
309
310	QueueHandle_t xQueueGenericCreateStatic( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, uint8_t pucQueueStorage, StaticQueue_t pxStaticQueue, const uint8_t ucQueueType )
311	{
312	Queue_t *pxNewQueue;
313
314	configASSERT( uxQueueLength > ( UBaseType_t ) 0 );
315
316	/* The StaticQueue_t structure and the queue storage area must be
317	supplied. */
318	configASSERT( pxStaticQueue != NULL );
319
320	/* A queue storage area should be provided if the item size is not 0, and
321	should not be provided if the item size is 0. */
322	configASSERT( !( ( pucQueueStorage != NULL ) && ( uxItemSize == 0 ) ) );
323	configASSERT( !( ( pucQueueStorage == NULL ) && ( uxItemSize != 0 ) ) );
324
325	#if( configASSERT_DEFINED == 1 )
326	{
327	/* Sanity check that the size of the structure used to declare a
328	variable of type StaticQueue_t or StaticSemaphore_t equals the size of
329	the real queue and semaphore structures. */
330	volatile size_t xSize = sizeof( StaticQueue_t );
331	configASSERT( xSize == sizeof( Queue_t ) );
332	( void ) xSize; /* Keeps lint quiet when configASSERT() is not defined. */
333	}
334	#endif /* configASSERT_DEFINED */
335
336	/* The address of a statically allocated queue was passed in, use it.
337	The address of a statically allocated storage area was also passed in
338	but is already set. */
339	pxNewQueue = ( Queue_t * ) pxStaticQueue; /lint !e740 !e9087 Unusual cast is ok as the structures are designed to have the same alignment, and the size is checked by an assert. /
340
341	if( pxNewQueue != NULL )
342	{
343	#if( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
344	{
345	/* Queues can be allocated wither statically or dynamically, so
346	note this queue was allocated statically in case the queue is
347	later deleted. */
348	pxNewQueue->ucStaticallyAllocated = pdTRUE;
349	}
350	#endif /* configSUPPORT_DYNAMIC_ALLOCATION */
351
352	prvInitialiseNewQueue( uxQueueLength, uxItemSize, pucQueueStorage, ucQueueType, pxNewQueue );
353	}
354	else
355	{
356	traceQUEUE_CREATE_FAILED( ucQueueType );
357	mtCOVERAGE_TEST_MARKER();
358	}
359
360	return pxNewQueue;
361	}
362
363	#endif /* configSUPPORT_STATIC_ALLOCATION */
364	/-----------------------------------------------------------/
365
366	#if( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
367
368	QueueHandle_t xQueueGenericCreate( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, const uint8_t ucQueueType )
369	{
370	Queue_t *pxNewQueue;
371	size_t xQueueSizeInBytes;
372	uint8_t *pucQueueStorage;
373
374	configASSERT( uxQueueLength > ( UBaseType_t ) 0 );
375
376	/* Allocate enough space to hold the maximum number of items that
377	can be in the queue at any time. It is valid for uxItemSize to be
378	zero in the case the queue is used as a semaphore. */
379	xQueueSizeInBytes = ( size_t ) ( uxQueueLength * uxItemSize ); /lint !e961 MISRA exception as the casts are only redundant for some ports. /
380
381	/* Allocate the queue and storage area. Justification for MISRA
382	deviation as follows: pvPortMalloc() always ensures returned memory
383	blocks are aligned per the requirements of the MCU stack. In this case
384	pvPortMalloc() must return a pointer that is guaranteed to meet the
385	alignment requirements of the Queue_t structure - which in this case
386	is an int8_t *. Therefore, whenever the stack alignment requirements
387	are greater than or equal to the pointer to char requirements the cast
388	is safe. In other cases alignment requirements are not strict (one or
389	two bytes). */
390	pxNewQueue = ( Queue_t * ) pvPortMalloc( sizeof( Queue_t ) + xQueueSizeInBytes ); /lint !e9087 !e9079 see comment above. /
391
392	if( pxNewQueue != NULL )
393	{
394	/* Jump past the queue structure to find the location of the queue
395	storage area. */
396	pucQueueStorage = ( uint8_t * ) pxNewQueue;
397	pucQueueStorage += sizeof( Queue_t ); /lint !e9016 Pointer arithmetic allowed on char types, especially when it assists conveying intent. /
398
399	#if( configSUPPORT_STATIC_ALLOCATION == 1 )
400	{
401	/* Queues can be created either statically or dynamically, so
402	note this task was created dynamically in case it is later
403	deleted. */
404	pxNewQueue->ucStaticallyAllocated = pdFALSE;
405	}
406	#endif /* configSUPPORT_STATIC_ALLOCATION */
407
408	prvInitialiseNewQueue( uxQueueLength, uxItemSize, pucQueueStorage, ucQueueType, pxNewQueue );
409	}
410	else
411	{
412	traceQUEUE_CREATE_FAILED( ucQueueType );
413	mtCOVERAGE_TEST_MARKER();
414	}
415
416	return pxNewQueue;
417	}
418
419	#endif /* configSUPPORT_STATIC_ALLOCATION */
420	/-----------------------------------------------------------/
421
422	static void prvInitialiseNewQueue( const UBaseType_t uxQueueLength, const UBaseType_t uxItemSize, uint8_t pucQueueStorage, const uint8_t ucQueueType, Queue_t pxNewQueue )
423	{
424	/* Remove compiler warnings about unused parameters should
425	configUSE_TRACE_FACILITY not be set to 1. */
426	( void ) ucQueueType;
427
428	if( uxItemSize == ( UBaseType_t ) 0 )
429	{
430	/* No RAM was allocated for the queue storage area, but PC head cannot
431	be set to NULL because NULL is used as a key to say the queue is used as
432	a mutex. Therefore just set pcHead to point to the queue as a benign
433	value that is known to be within the memory map. */
434	pxNewQueue->pcHead = ( int8_t * ) pxNewQueue;
435	}
436	else
437	{
438	/* Set the head to the start of the queue storage area. */
439	pxNewQueue->pcHead = ( int8_t * ) pucQueueStorage;
440	}
441
442	/* Initialise the queue members as described where the queue type is
443	defined. */
444	pxNewQueue->uxLength = uxQueueLength;
445	pxNewQueue->uxItemSize = uxItemSize;
446	( void ) xQueueGenericReset( pxNewQueue, pdTRUE );
447
448	#if ( configUSE_TRACE_FACILITY == 1 )
449	{
450	pxNewQueue->ucQueueType = ucQueueType;
451	}
452	#endif /* configUSE_TRACE_FACILITY */
453
454	#if( configUSE_QUEUE_SETS == 1 )
455	{
456	pxNewQueue->pxQueueSetContainer = NULL;
457	}
458	#endif /* configUSE_QUEUE_SETS */
459
460	traceQUEUE_CREATE( pxNewQueue );
461	}
462	/-----------------------------------------------------------/
463
464	#if( configUSE_MUTEXES == 1 )
465
466	static void prvInitialiseMutex( Queue_t *pxNewQueue )
467	{
468	if( pxNewQueue != NULL )
469	{
470	/* The queue create function will set all the queue structure members
471	correctly for a generic queue, but this function is creating a
472	mutex. Overwrite those members that need to be set differently -
473	in particular the information required for priority inheritance. */
474	pxNewQueue->u.xSemaphore.xMutexHolder = NULL;
475	pxNewQueue->uxQueueType = queueQUEUE_IS_MUTEX;
476
477	/* In case this is a recursive mutex. */
478	pxNewQueue->u.xSemaphore.uxRecursiveCallCount = 0;
479
480	traceCREATE_MUTEX( pxNewQueue );
481
482	/* Start with the semaphore in the expected state. */
483	( void ) xQueueGenericSend( pxNewQueue, NULL, ( TickType_t ) 0U, queueSEND_TO_BACK );
484	}
485	else
486	{
487	traceCREATE_MUTEX_FAILED();
488	}
489	}
490
491	#endif /* configUSE_MUTEXES */
492	/-----------------------------------------------------------/
493
494	#if( ( configUSE_MUTEXES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
495
496	QueueHandle_t xQueueCreateMutex( const uint8_t ucQueueType )
497	{
498	QueueHandle_t xNewQueue;
499	const UBaseType_t uxMutexLength = ( UBaseType_t ) 1, uxMutexSize = ( UBaseType_t ) 0;
500
501	xNewQueue = xQueueGenericCreate( uxMutexLength, uxMutexSize, ucQueueType );
502	prvInitialiseMutex( ( Queue_t * ) xNewQueue );
503
504	return xNewQueue;
505	}
506
507	#endif /* configUSE_MUTEXES */
508	/-----------------------------------------------------------/
509
510	#if( ( configUSE_MUTEXES == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
511
512	QueueHandle_t xQueueCreateMutexStatic( const uint8_t ucQueueType, StaticQueue_t *pxStaticQueue )
513	{
514	QueueHandle_t xNewQueue;
515	const UBaseType_t uxMutexLength = ( UBaseType_t ) 1, uxMutexSize = ( UBaseType_t ) 0;
516
517	/* Prevent compiler warnings about unused parameters if
518	configUSE_TRACE_FACILITY does not equal 1. */
519	( void ) ucQueueType;
520
521	xNewQueue = xQueueGenericCreateStatic( uxMutexLength, uxMutexSize, NULL, pxStaticQueue, ucQueueType );
522	prvInitialiseMutex( ( Queue_t * ) xNewQueue );
523
524	return xNewQueue;
525	}
526
527	#endif /* configUSE_MUTEXES */
528	/-----------------------------------------------------------/
529
530	#if ( ( configUSE_MUTEXES == 1 ) && ( INCLUDE_xSemaphoreGetMutexHolder == 1 ) )
531
532	TaskHandle_t xQueueGetMutexHolder( QueueHandle_t xSemaphore )
533	{
534	TaskHandle_t pxReturn;
535	Queue_t * const pxSemaphore = ( Queue_t * ) xSemaphore;
536
537	/* This function is called by xSemaphoreGetMutexHolder(), and should not
538	be called directly. Note: This is a good way of determining if the
539	calling task is the mutex holder, but not a good way of determining the
540	identity of the mutex holder, as the holder may change between the
541	following critical section exiting and the function returning. */
542	taskENTER_CRITICAL();
543	{
544	if( pxSemaphore->uxQueueType == queueQUEUE_IS_MUTEX )
545	{
546	pxReturn = pxSemaphore->u.xSemaphore.xMutexHolder;
547	}
548	else
549	{
550	pxReturn = NULL;
551	}
552	}
553	taskEXIT_CRITICAL();
554
555	return pxReturn;
556	} /lint !e818 xSemaphore cannot be a pointer to const because it is a typedef. /
557
558	#endif
559	/-----------------------------------------------------------/
560
561	#if ( ( configUSE_MUTEXES == 1 ) && ( INCLUDE_xSemaphoreGetMutexHolder == 1 ) )
562
563	TaskHandle_t xQueueGetMutexHolderFromISR( QueueHandle_t xSemaphore )
564	{
565	TaskHandle_t pxReturn;
566
567	configASSERT( xSemaphore );
568
569	/* Mutexes cannot be used in interrupt service routines, so the mutex
570	holder should not change in an ISR, and therefore a critical section is
571	not required here. */
572	if( ( ( Queue_t * ) xSemaphore )->uxQueueType == queueQUEUE_IS_MUTEX )
573	{
574	pxReturn = ( ( Queue_t * ) xSemaphore )->u.xSemaphore.xMutexHolder;
575	}
576	else
577	{
578	pxReturn = NULL;
579	}
580
581	return pxReturn;
582	} /lint !e818 xSemaphore cannot be a pointer to const because it is a typedef. /
583
584	#endif
585	/-----------------------------------------------------------/
586
587	#if ( configUSE_RECURSIVE_MUTEXES == 1 )
588
589	BaseType_t xQueueGiveMutexRecursive( QueueHandle_t xMutex )
590	{
591	BaseType_t xReturn;
592	Queue_t * const pxMutex = ( Queue_t * ) xMutex;
593
594	configASSERT( pxMutex );
595
596	/* If this is the task that holds the mutex then xMutexHolder will not
597	change outside of this task. If this task does not hold the mutex then
598	pxMutexHolder can never coincidentally equal the tasks handle, and as
599	this is the only condition we are interested in it does not matter if
600	pxMutexHolder is accessed simultaneously by another task. Therefore no
601	mutual exclusion is required to test the pxMutexHolder variable. */
602	if( pxMutex->u.xSemaphore.xMutexHolder == xTaskGetCurrentTaskHandle() )
603	{
604	traceGIVE_MUTEX_RECURSIVE( pxMutex );
605
606	/* uxRecursiveCallCount cannot be zero if xMutexHolder is equal to
607	the task handle, therefore no underflow check is required. Also,
608	uxRecursiveCallCount is only modified by the mutex holder, and as
609	there can only be one, no mutual exclusion is required to modify the
610	uxRecursiveCallCount member. */
611	( pxMutex->u.xSemaphore.uxRecursiveCallCount )--;
612
613	/* Has the recursive call count unwound to 0? */
614	if( pxMutex->u.xSemaphore.uxRecursiveCallCount == ( UBaseType_t ) 0 )
615	{
616	/* Return the mutex. This will automatically unblock any other
617	task that might be waiting to access the mutex. */
618	( void ) xQueueGenericSend( pxMutex, NULL, queueMUTEX_GIVE_BLOCK_TIME, queueSEND_TO_BACK );
619	}
620	else
621	{
622	mtCOVERAGE_TEST_MARKER();
623	}
624
625	xReturn = pdPASS;
626	}
627	else
628	{
629	/* The mutex cannot be given because the calling task is not the
630	holder. */
631	xReturn = pdFAIL;
632
633	traceGIVE_MUTEX_RECURSIVE_FAILED( pxMutex );
634	}
635
636	return xReturn;
637	}
638
639	#endif /* configUSE_RECURSIVE_MUTEXES */
640	/-----------------------------------------------------------/
641
642	#if ( configUSE_RECURSIVE_MUTEXES == 1 )
643
644	BaseType_t xQueueTakeMutexRecursive( QueueHandle_t xMutex, TickType_t xTicksToWait )
645	{
646	BaseType_t xReturn;
647	Queue_t * const pxMutex = ( Queue_t * ) xMutex;
648
649	configASSERT( pxMutex );
650
651	/* Comments regarding mutual exclusion as per those within
652	xQueueGiveMutexRecursive(). */
653
654	traceTAKE_MUTEX_RECURSIVE( pxMutex );
655
656	if( pxMutex->u.xSemaphore.xMutexHolder == xTaskGetCurrentTaskHandle() )
657	{
658	( pxMutex->u.xSemaphore.uxRecursiveCallCount )++;
659	xReturn = pdPASS;
660	}
661	else
662	{
663	xReturn = xQueueSemaphoreTake( pxMutex, xTicksToWait );
664
665	/* pdPASS will only be returned if the mutex was successfully
666	obtained. The calling task may have entered the Blocked state
667	before reaching here. */
668	if( xReturn != pdFAIL )
669	{
670	( pxMutex->u.xSemaphore.uxRecursiveCallCount )++;
671	}
672	else
673	{
674	traceTAKE_MUTEX_RECURSIVE_FAILED( pxMutex );
675	}
676	}
677
678	return xReturn;
679	}
680
681	#endif /* configUSE_RECURSIVE_MUTEXES */
682	/-----------------------------------------------------------/
683
684	#if( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
685
686	QueueHandle_t xQueueCreateCountingSemaphoreStatic( const UBaseType_t uxMaxCount, const UBaseType_t uxInitialCount, StaticQueue_t *pxStaticQueue )
687	{
688	QueueHandle_t xHandle;
689
690	configASSERT( uxMaxCount != 0 );
691	configASSERT( uxInitialCount <= uxMaxCount );
692
693	xHandle = xQueueGenericCreateStatic( uxMaxCount, queueSEMAPHORE_QUEUE_ITEM_LENGTH, NULL, pxStaticQueue, queueQUEUE_TYPE_COUNTING_SEMAPHORE );
694
695	if( xHandle != NULL )
696	{
697	( ( Queue_t * ) xHandle )->uxMessagesWaiting = uxInitialCount;
698
699	traceCREATE_COUNTING_SEMAPHORE();
700	}
701	else
702	{
703	traceCREATE_COUNTING_SEMAPHORE_FAILED();
704	}
705
706	return xHandle;
707	}
708
709	#endif /* ( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) ) */
710	/-----------------------------------------------------------/
711
712	#if( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
713
714	QueueHandle_t xQueueCreateCountingSemaphore( const UBaseType_t uxMaxCount, const UBaseType_t uxInitialCount )
715	{
716	QueueHandle_t xHandle;
717
718	configASSERT( uxMaxCount != 0 );
719	configASSERT( uxInitialCount <= uxMaxCount );
720
721	xHandle = xQueueGenericCreate( uxMaxCount, queueSEMAPHORE_QUEUE_ITEM_LENGTH, queueQUEUE_TYPE_COUNTING_SEMAPHORE );
722
723	if( xHandle != NULL )
724	{
725	( ( Queue_t * ) xHandle )->uxMessagesWaiting = uxInitialCount;
726
727	traceCREATE_COUNTING_SEMAPHORE();
728	}
729	else
730	{
731	traceCREATE_COUNTING_SEMAPHORE_FAILED();
732	}
733
734	return xHandle;
735	}
736
737	#endif /* ( ( configUSE_COUNTING_SEMAPHORES == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) ) */
738	/-----------------------------------------------------------/
739
740	BaseType_t xQueueGenericSend( QueueHandle_t xQueue, const void * const pvItemToQueue, TickType_t xTicksToWait, const BaseType_t xCopyPosition )
741	{
742	BaseType_t xEntryTimeSet = pdFALSE, xYieldRequired;
743	TimeOut_t xTimeOut;
744	Queue_t * const pxQueue = xQueue;
745
746	configASSERT( pxQueue );
747	configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
748	configASSERT( !( ( xCopyPosition == queueOVERWRITE ) && ( pxQueue->uxLength != 1 ) ) );
749	#if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) \|\| ( configUSE_TIMERS == 1 ) )
750	{
751	configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
752	}
753	#endif
754
755
756	/*lint -save -e904 This function relaxes the coding standard somewhat to
757	allow return statements within the function itself. This is done in the
758	interest of execution time efficiency. */
759	for( ;; )
760	{
761	taskENTER_CRITICAL();
762	{
763	/* Is there room on the queue now? The running task must be the
764	highest priority task wanting to access the queue. If the head item
765	in the queue is to be overwritten then it does not matter if the
766	queue is full. */
767	if( ( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) \|\| ( xCopyPosition == queueOVERWRITE ) )
768	{
769	traceQUEUE_SEND( pxQueue );
770
771	#if ( configUSE_QUEUE_SETS == 1 )
772	{
773	const UBaseType_t uxPreviousMessagesWaiting = pxQueue->uxMessagesWaiting;
774
775	xYieldRequired = prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
776
777	if( pxQueue->pxQueueSetContainer != NULL )
778	{
779	if( ( xCopyPosition == queueOVERWRITE ) && ( uxPreviousMessagesWaiting != ( UBaseType_t ) 0 ) )
780	{
781	/* Do not notify the queue set as an existing item
782	was overwritten in the queue so the number of items
783	in the queue has not changed. */
784	mtCOVERAGE_TEST_MARKER();
785	}
786	else if( prvNotifyQueueSetContainer( pxQueue ) != pdFALSE )
787	{
788	/* The queue is a member of a queue set, and posting
789	to the queue set caused a higher priority task to
790	unblock. A context switch is required. */
791	queueYIELD_IF_USING_PREEMPTION();
792	}
793	else
794	{
795	mtCOVERAGE_TEST_MARKER();
796	}
797	}
798	else
799	{
800	/* If there was a task waiting for data to arrive on the
801	queue then unblock it now. */
802	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
803	{
804	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
805	{
806	/* The unblocked task has a priority higher than
807	our own so yield immediately. Yes it is ok to
808	do this from within the critical section - the
809	kernel takes care of that. */
810	queueYIELD_IF_USING_PREEMPTION();
811	}
812	else
813	{
814	mtCOVERAGE_TEST_MARKER();
815	}
816	}
817	else if( xYieldRequired != pdFALSE )
818	{
819	/* This path is a special case that will only get
820	executed if the task was holding multiple mutexes
821	and the mutexes were given back in an order that is
822	different to that in which they were taken. */
823	queueYIELD_IF_USING_PREEMPTION();
824	}
825	else
826	{
827	mtCOVERAGE_TEST_MARKER();
828	}
829	}
830	}
831	#else /* configUSE_QUEUE_SETS */
832	{
833	xYieldRequired = prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
834
835	/* If there was a task waiting for data to arrive on the
836	queue then unblock it now. */
837	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
838	{
839	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
840	{
841	/* The unblocked task has a priority higher than
842	our own so yield immediately. Yes it is ok to do
843	this from within the critical section - the kernel
844	takes care of that. */
845	queueYIELD_IF_USING_PREEMPTION();
846	}
847	else
848	{
849	mtCOVERAGE_TEST_MARKER();
850	}
851	}
852	else if( xYieldRequired != pdFALSE )
853	{
854	/* This path is a special case that will only get
855	executed if the task was holding multiple mutexes and
856	the mutexes were given back in an order that is
857	different to that in which they were taken. */
858	queueYIELD_IF_USING_PREEMPTION();
859	}
860	else
861	{
862	mtCOVERAGE_TEST_MARKER();
863	}
864	}
865	#endif /* configUSE_QUEUE_SETS */
866
867	taskEXIT_CRITICAL();
868	return pdPASS;
869	}
870	else
871	{
872	if( xTicksToWait == ( TickType_t ) 0 )
873	{
874	/* The queue was full and no block time is specified (or
875	the block time has expired) so leave now. */
876	taskEXIT_CRITICAL();
877
878	/* Return to the original privilege level before exiting
879	the function. */
880	traceQUEUE_SEND_FAILED( pxQueue );
881	return errQUEUE_FULL;
882	}
883	else if( xEntryTimeSet == pdFALSE )
884	{
885	/* The queue was full and a block time was specified so
886	configure the timeout structure. */
887	vTaskInternalSetTimeOutState( &xTimeOut );
888	xEntryTimeSet = pdTRUE;
889	}
890	else
891	{
892	/* Entry time was already set. */
893	mtCOVERAGE_TEST_MARKER();
894	}
895	}
896	}
897	taskEXIT_CRITICAL();
898
899	/* Interrupts and other tasks can send to and receive from the queue
900	now the critical section has been exited. */
901
902	vTaskSuspendAll();
903	prvLockQueue( pxQueue );
904
905	/* Update the timeout state to see if it has expired yet. */
906	if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
907	{
908	if( prvIsQueueFull( pxQueue ) != pdFALSE )
909	{
910	traceBLOCKING_ON_QUEUE_SEND( pxQueue );
911	vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToSend ), xTicksToWait );
912
913	/* Unlocking the queue means queue events can effect the
914	event list. It is possible that interrupts occurring now
915	remove this task from the event list again - but as the
916	scheduler is suspended the task will go onto the pending
917	ready last instead of the actual ready list. */
918	prvUnlockQueue( pxQueue );
919
920	/* Resuming the scheduler will move tasks from the pending
921	ready list into the ready list - so it is feasible that this
922	task is already in a ready list before it yields - in which
923	case the yield will not cause a context switch unless there
924	is also a higher priority task in the pending ready list. */
925	if( xTaskResumeAll() == pdFALSE )
926	{
927	portYIELD_WITHIN_API();
928	}
929	}
930	else
931	{
932	/* Try again. */
933	prvUnlockQueue( pxQueue );
934	( void ) xTaskResumeAll();
935	}
936	}
937	else
938	{
939	/* The timeout has expired. */
940	prvUnlockQueue( pxQueue );
941	( void ) xTaskResumeAll();
942
943	traceQUEUE_SEND_FAILED( pxQueue );
944	return errQUEUE_FULL;
945	}
946	} /lint -restore /
947	}
948	/-----------------------------------------------------------/
949
950	BaseType_t xQueueGenericSendFromISR( QueueHandle_t xQueue, const void * const pvItemToQueue, BaseType_t * const pxHigherPriorityTaskWoken, const BaseType_t xCopyPosition )
951	{
952	BaseType_t xReturn;
953	UBaseType_t uxSavedInterruptStatus;
954	Queue_t * const pxQueue = xQueue;
955
956	configASSERT( pxQueue );
957	configASSERT( !( ( pvItemToQueue == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
958	configASSERT( !( ( xCopyPosition == queueOVERWRITE ) && ( pxQueue->uxLength != 1 ) ) );
959
960	/* RTOS ports that support interrupt nesting have the concept of a maximum
961	system call (or maximum API call) interrupt priority. Interrupts that are
962	above the maximum system call priority are kept permanently enabled, even
963	when the RTOS kernel is in a critical section, but cannot make any calls to
964	FreeRTOS API functions. If configASSERT() is defined in FreeRTOSConfig.h
965	then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
966	failure if a FreeRTOS API function is called from an interrupt that has been
967	assigned a priority above the configured maximum system call priority.
968	Only FreeRTOS functions that end in FromISR can be called from interrupts
969	that have been assigned a priority at or (logically) below the maximum
970	system call interrupt priority. FreeRTOS maintains a separate interrupt
971	safe API to ensure interrupt entry is as fast and as simple as possible.
972	More information (albeit Cortex-M specific) is provided on the following
973	link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
974	portASSERT_IF_INTERRUPT_PRIORITY_INVALID();
975
976	/* Similar to xQueueGenericSend, except without blocking if there is no room
977	in the queue. Also don't directly wake a task that was blocked on a queue
978	read, instead return a flag to say whether a context switch is required or
979	not (i.e. has a task with a higher priority than us been woken by this
980	post). */
981	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
982	{
983	if( ( pxQueue->uxMessagesWaiting < pxQueue->uxLength ) \|\| ( xCopyPosition == queueOVERWRITE ) )
984	{
985	const int8_t cTxLock = pxQueue->cTxLock;
986	const UBaseType_t uxPreviousMessagesWaiting = pxQueue->uxMessagesWaiting;
987
988	traceQUEUE_SEND_FROM_ISR( pxQueue );
989
990	/* Semaphores use xQueueGiveFromISR(), so pxQueue will not be a
991	semaphore or mutex. That means prvCopyDataToQueue() cannot result
992	in a task disinheriting a priority and prvCopyDataToQueue() can be
993	called here even though the disinherit function does not check if
994	the scheduler is suspended before accessing the ready lists. */
995	( void ) prvCopyDataToQueue( pxQueue, pvItemToQueue, xCopyPosition );
996
997	/* The event list is not altered if the queue is locked. This will
998	be done when the queue is unlocked later. */
999	if( cTxLock == queueUNLOCKED )
1000	{
1001	#if ( configUSE_QUEUE_SETS == 1 )
1002	{
1003	if( pxQueue->pxQueueSetContainer != NULL )
1004	{
1005	if( ( xCopyPosition == queueOVERWRITE ) && ( uxPreviousMessagesWaiting != ( UBaseType_t ) 0 ) )
1006	{
1007	/* Do not notify the queue set as an existing item
1008	was overwritten in the queue so the number of items
1009	in the queue has not changed. */
1010	mtCOVERAGE_TEST_MARKER();
1011	}
1012	else if( prvNotifyQueueSetContainer( pxQueue ) != pdFALSE )
1013	{
1014	/* The queue is a member of a queue set, and posting
1015	to the queue set caused a higher priority task to
1016	unblock. A context switch is required. */
1017	if( pxHigherPriorityTaskWoken != NULL )
1018	{
1019	*pxHigherPriorityTaskWoken = pdTRUE;
1020	}
1021	else
1022	{
1023	mtCOVERAGE_TEST_MARKER();
1024	}
1025	}
1026	else
1027	{
1028	mtCOVERAGE_TEST_MARKER();
1029	}
1030	}
1031	else
1032	{
1033	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1034	{
1035	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1036	{
1037	/* The task waiting has a higher priority so
1038	record that a context switch is required. */
1039	if( pxHigherPriorityTaskWoken != NULL )
1040	{
1041	*pxHigherPriorityTaskWoken = pdTRUE;
1042	}
1043	else
1044	{
1045	mtCOVERAGE_TEST_MARKER();
1046	}
1047	}
1048	else
1049	{
1050	mtCOVERAGE_TEST_MARKER();
1051	}
1052	}
1053	else
1054	{
1055	mtCOVERAGE_TEST_MARKER();
1056	}
1057	}
1058	}
1059	#else /* configUSE_QUEUE_SETS */
1060	{
1061	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1062	{
1063	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1064	{
1065	/* The task waiting has a higher priority so record that a
1066	context switch is required. */
1067	if( pxHigherPriorityTaskWoken != NULL )
1068	{
1069	*pxHigherPriorityTaskWoken = pdTRUE;
1070	}
1071	else
1072	{
1073	mtCOVERAGE_TEST_MARKER();
1074	}
1075	}
1076	else
1077	{
1078	mtCOVERAGE_TEST_MARKER();
1079	}
1080	}
1081	else
1082	{
1083	mtCOVERAGE_TEST_MARKER();
1084	}
1085
1086	/* Not used in this path. */
1087	( void ) uxPreviousMessagesWaiting;
1088	}
1089	#endif /* configUSE_QUEUE_SETS */
1090	}
1091	else
1092	{
1093	/* Increment the lock count so the task that unlocks the queue
1094	knows that data was posted while it was locked. */
1095	pxQueue->cTxLock = ( int8_t ) ( cTxLock + 1 );
1096	}
1097
1098	xReturn = pdPASS;
1099	}
1100	else
1101	{
1102	traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );
1103	xReturn = errQUEUE_FULL;
1104	}
1105	}
1106	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1107
1108	return xReturn;
1109	}
1110	/-----------------------------------------------------------/
1111
1112	BaseType_t xQueueGiveFromISR( QueueHandle_t xQueue, BaseType_t * const pxHigherPriorityTaskWoken )
1113	{
1114	BaseType_t xReturn;
1115	UBaseType_t uxSavedInterruptStatus;
1116	Queue_t * const pxQueue = xQueue;
1117
1118	/* Similar to xQueueGenericSendFromISR() but used with semaphores where the
1119	item size is 0. Don't directly wake a task that was blocked on a queue
1120	read, instead return a flag to say whether a context switch is required or
1121	not (i.e. has a task with a higher priority than us been woken by this
1122	post). */
1123
1124	configASSERT( pxQueue );
1125
1126	/* xQueueGenericSendFromISR() should be used instead of xQueueGiveFromISR()
1127	if the item size is not 0. */
1128	configASSERT( pxQueue->uxItemSize == 0 );
1129
1130	/* Normally a mutex would not be given from an interrupt, especially if
1131	there is a mutex holder, as priority inheritance makes no sense for an
1132	interrupts, only tasks. */
1133	configASSERT( !( ( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX ) && ( pxQueue->u.xSemaphore.xMutexHolder != NULL ) ) );
1134
1135	/* RTOS ports that support interrupt nesting have the concept of a maximum
1136	system call (or maximum API call) interrupt priority. Interrupts that are
1137	above the maximum system call priority are kept permanently enabled, even
1138	when the RTOS kernel is in a critical section, but cannot make any calls to
1139	FreeRTOS API functions. If configASSERT() is defined in FreeRTOSConfig.h
1140	then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
1141	failure if a FreeRTOS API function is called from an interrupt that has been
1142	assigned a priority above the configured maximum system call priority.
1143	Only FreeRTOS functions that end in FromISR can be called from interrupts
1144	that have been assigned a priority at or (logically) below the maximum
1145	system call interrupt priority. FreeRTOS maintains a separate interrupt
1146	safe API to ensure interrupt entry is as fast and as simple as possible.
1147	More information (albeit Cortex-M specific) is provided on the following
1148	link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
1149	portASSERT_IF_INTERRUPT_PRIORITY_INVALID();
1150
1151	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
1152	{
1153	const UBaseType_t uxMessagesWaiting = pxQueue->uxMessagesWaiting;
1154
1155	/* When the queue is used to implement a semaphore no data is ever
1156	moved through the queue but it is still valid to see if the queue 'has
1157	space'. */
1158	if( uxMessagesWaiting < pxQueue->uxLength )
1159	{
1160	const int8_t cTxLock = pxQueue->cTxLock;
1161
1162	traceQUEUE_SEND_FROM_ISR( pxQueue );
1163
1164	/* A task can only have an inherited priority if it is a mutex
1165	holder - and if there is a mutex holder then the mutex cannot be
1166	given from an ISR. As this is the ISR version of the function it
1167	can be assumed there is no mutex holder and no need to determine if
1168	priority disinheritance is needed. Simply increase the count of
1169	messages (semaphores) available. */
1170	pxQueue->uxMessagesWaiting = uxMessagesWaiting + ( UBaseType_t ) 1;
1171
1172	/* The event list is not altered if the queue is locked. This will
1173	be done when the queue is unlocked later. */
1174	if( cTxLock == queueUNLOCKED )
1175	{
1176	#if ( configUSE_QUEUE_SETS == 1 )
1177	{
1178	if( pxQueue->pxQueueSetContainer != NULL )
1179	{
1180	if( prvNotifyQueueSetContainer( pxQueue ) != pdFALSE )
1181	{
1182	/* The semaphore is a member of a queue set, and
1183	posting to the queue set caused a higher priority
1184	task to unblock. A context switch is required. */
1185	if( pxHigherPriorityTaskWoken != NULL )
1186	{
1187	*pxHigherPriorityTaskWoken = pdTRUE;
1188	}
1189	else
1190	{
1191	mtCOVERAGE_TEST_MARKER();
1192	}
1193	}
1194	else
1195	{
1196	mtCOVERAGE_TEST_MARKER();
1197	}
1198	}
1199	else
1200	{
1201	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1202	{
1203	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1204	{
1205	/* The task waiting has a higher priority so
1206	record that a context switch is required. */
1207	if( pxHigherPriorityTaskWoken != NULL )
1208	{
1209	*pxHigherPriorityTaskWoken = pdTRUE;
1210	}
1211	else
1212	{
1213	mtCOVERAGE_TEST_MARKER();
1214	}
1215	}
1216	else
1217	{
1218	mtCOVERAGE_TEST_MARKER();
1219	}
1220	}
1221	else
1222	{
1223	mtCOVERAGE_TEST_MARKER();
1224	}
1225	}
1226	}
1227	#else /* configUSE_QUEUE_SETS */
1228	{
1229	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1230	{
1231	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1232	{
1233	/* The task waiting has a higher priority so record that a
1234	context switch is required. */
1235	if( pxHigherPriorityTaskWoken != NULL )
1236	{
1237	*pxHigherPriorityTaskWoken = pdTRUE;
1238	}
1239	else
1240	{
1241	mtCOVERAGE_TEST_MARKER();
1242	}
1243	}
1244	else
1245	{
1246	mtCOVERAGE_TEST_MARKER();
1247	}
1248	}
1249	else
1250	{
1251	mtCOVERAGE_TEST_MARKER();
1252	}
1253	}
1254	#endif /* configUSE_QUEUE_SETS */
1255	}
1256	else
1257	{
1258	/* Increment the lock count so the task that unlocks the queue
1259	knows that data was posted while it was locked. */
1260	pxQueue->cTxLock = ( int8_t ) ( cTxLock + 1 );
1261	}
1262
1263	xReturn = pdPASS;
1264	}
1265	else
1266	{
1267	traceQUEUE_SEND_FROM_ISR_FAILED( pxQueue );
1268	xReturn = errQUEUE_FULL;
1269	}
1270	}
1271	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1272
1273	return xReturn;
1274	}
1275	/-----------------------------------------------------------/
1276
1277	BaseType_t xQueueReceive( QueueHandle_t xQueue, void * const pvBuffer, TickType_t xTicksToWait )
1278	{
1279	BaseType_t xEntryTimeSet = pdFALSE;
1280	TimeOut_t xTimeOut;
1281	Queue_t * const pxQueue = xQueue;
1282
1283	/* Check the pointer is not NULL. */
1284	configASSERT( ( pxQueue ) );
1285
1286	/* The buffer into which data is received can only be NULL if the data size
1287	is zero (so no data is copied into the buffer. */
1288	configASSERT( !( ( ( pvBuffer ) == NULL ) && ( ( pxQueue )->uxItemSize != ( UBaseType_t ) 0U ) ) );
1289
1290	/* Cannot block if the scheduler is suspended. */
1291	#if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) \|\| ( configUSE_TIMERS == 1 ) )
1292	{
1293	configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
1294	}
1295	#endif
1296
1297
1298	/*lint -save -e904 This function relaxes the coding standard somewhat to
1299	allow return statements within the function itself. This is done in the
1300	interest of execution time efficiency. */
1301	for( ;; )
1302	{
1303	taskENTER_CRITICAL();
1304	{
1305	const UBaseType_t uxMessagesWaiting = pxQueue->uxMessagesWaiting;
1306
1307	/* Is there data in the queue now? To be running the calling task
1308	must be the highest priority task wanting to access the queue. */
1309	if( uxMessagesWaiting > ( UBaseType_t ) 0 )
1310	{
1311	/* Data available, remove one item. */
1312	prvCopyDataFromQueue( pxQueue, pvBuffer );
1313	traceQUEUE_RECEIVE( pxQueue );
1314	pxQueue->uxMessagesWaiting = uxMessagesWaiting - ( UBaseType_t ) 1;
1315
1316	/* There is now space in the queue, were any tasks waiting to
1317	post to the queue? If so, unblock the highest priority waiting
1318	task. */
1319	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
1320	{
1321	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
1322	{
1323	queueYIELD_IF_USING_PREEMPTION();
1324	}
1325	else
1326	{
1327	mtCOVERAGE_TEST_MARKER();
1328	}
1329	}
1330	else
1331	{
1332	mtCOVERAGE_TEST_MARKER();
1333	}
1334
1335	taskEXIT_CRITICAL();
1336	return pdPASS;
1337	}
1338	else
1339	{
1340	if( xTicksToWait == ( TickType_t ) 0 )
1341	{
1342	/* The queue was empty and no block time is specified (or
1343	the block time has expired) so leave now. */
1344	taskEXIT_CRITICAL();
1345	traceQUEUE_RECEIVE_FAILED( pxQueue );
1346	return errQUEUE_EMPTY;
1347	}
1348	else if( xEntryTimeSet == pdFALSE )
1349	{
1350	/* The queue was empty and a block time was specified so
1351	configure the timeout structure. */
1352	vTaskInternalSetTimeOutState( &xTimeOut );
1353	xEntryTimeSet = pdTRUE;
1354	}
1355	else
1356	{
1357	/* Entry time was already set. */
1358	mtCOVERAGE_TEST_MARKER();
1359	}
1360	}
1361	}
1362	taskEXIT_CRITICAL();
1363
1364	/* Interrupts and other tasks can send to and receive from the queue
1365	now the critical section has been exited. */
1366
1367	vTaskSuspendAll();
1368	prvLockQueue( pxQueue );
1369
1370	/* Update the timeout state to see if it has expired yet. */
1371	if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
1372	{
1373	/* The timeout has not expired. If the queue is still empty place
1374	the task on the list of tasks waiting to receive from the queue. */
1375	if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1376	{
1377	traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );
1378	vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
1379	prvUnlockQueue( pxQueue );
1380	if( xTaskResumeAll() == pdFALSE )
1381	{
1382	portYIELD_WITHIN_API();
1383	}
1384	else
1385	{
1386	mtCOVERAGE_TEST_MARKER();
1387	}
1388	}
1389	else
1390	{
1391	/* The queue contains data again. Loop back to try and read the
1392	data. */
1393	prvUnlockQueue( pxQueue );
1394	( void ) xTaskResumeAll();
1395	}
1396	}
1397	else
1398	{
1399	/* Timed out. If there is no data in the queue exit, otherwise loop
1400	back and attempt to read the data. */
1401	prvUnlockQueue( pxQueue );
1402	( void ) xTaskResumeAll();
1403
1404	if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1405	{
1406	traceQUEUE_RECEIVE_FAILED( pxQueue );
1407	return errQUEUE_EMPTY;
1408	}
1409	else
1410	{
1411	mtCOVERAGE_TEST_MARKER();
1412	}
1413	}
1414	} /lint -restore /
1415	}
1416	/-----------------------------------------------------------/
1417
1418	BaseType_t xQueueSemaphoreTake( QueueHandle_t xQueue, TickType_t xTicksToWait )
1419	{
1420	BaseType_t xEntryTimeSet = pdFALSE;
1421	TimeOut_t xTimeOut;
1422	Queue_t * const pxQueue = xQueue;
1423
1424	#if( configUSE_MUTEXES == 1 )
1425	BaseType_t xInheritanceOccurred = pdFALSE;
1426	#endif
1427
1428	/* Check the queue pointer is not NULL. */
1429	configASSERT( ( pxQueue ) );
1430
1431	/* Check this really is a semaphore, in which case the item size will be
1432	0. */
1433	configASSERT( pxQueue->uxItemSize == 0 );
1434
1435	/* Cannot block if the scheduler is suspended. */
1436	#if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) \|\| ( configUSE_TIMERS == 1 ) )
1437	{
1438	configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
1439	}
1440	#endif
1441
1442
1443	/*lint -save -e904 This function relaxes the coding standard somewhat to allow return
1444	statements within the function itself. This is done in the interest
1445	of execution time efficiency. */
1446	for( ;; )
1447	{
1448	taskENTER_CRITICAL();
1449	{
1450	/* Semaphores are queues with an item size of 0, and where the
1451	number of messages in the queue is the semaphore's count value. */
1452	const UBaseType_t uxSemaphoreCount = pxQueue->uxMessagesWaiting;
1453
1454	/* Is there data in the queue now? To be running the calling task
1455	must be the highest priority task wanting to access the queue. */
1456	if( uxSemaphoreCount > ( UBaseType_t ) 0 )
1457	{
1458	traceQUEUE_RECEIVE( pxQueue );
1459
1460	/* Semaphores are queues with a data size of zero and where the
1461	messages waiting is the semaphore's count. Reduce the count. */
1462	pxQueue->uxMessagesWaiting = uxSemaphoreCount - ( UBaseType_t ) 1;
1463
1464	#if ( configUSE_MUTEXES == 1 )
1465	{
1466	if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
1467	{
1468	/* Record the information required to implement
1469	priority inheritance should it become necessary. */
1470	pxQueue->u.xSemaphore.xMutexHolder = pvTaskIncrementMutexHeldCount();
1471	}
1472	else
1473	{
1474	mtCOVERAGE_TEST_MARKER();
1475	}
1476	}
1477	#endif /* configUSE_MUTEXES */
1478
1479	/* Check to see if other tasks are blocked waiting to give the
1480	semaphore, and if so, unblock the highest priority such task. */
1481	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
1482	{
1483	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
1484	{
1485	queueYIELD_IF_USING_PREEMPTION();
1486	}
1487	else
1488	{
1489	mtCOVERAGE_TEST_MARKER();
1490	}
1491	}
1492	else
1493	{
1494	mtCOVERAGE_TEST_MARKER();
1495	}
1496
1497	taskEXIT_CRITICAL();
1498	return pdPASS;
1499	}
1500	else
1501	{
1502	if( xTicksToWait == ( TickType_t ) 0 )
1503	{
1504	/* For inheritance to have occurred there must have been an
1505	initial timeout, and an adjusted timeout cannot become 0, as
1506	if it were 0 the function would have exited. */
1507	#if( configUSE_MUTEXES == 1 )
1508	{
1509	configASSERT( xInheritanceOccurred == pdFALSE );
1510	}
1511	#endif /* configUSE_MUTEXES */
1512
1513	/* The semaphore count was 0 and no block time is specified
1514	(or the block time has expired) so exit now. */
1515	taskEXIT_CRITICAL();
1516	traceQUEUE_RECEIVE_FAILED( pxQueue );
1517	return errQUEUE_EMPTY;
1518	}
1519	else if( xEntryTimeSet == pdFALSE )
1520	{
1521	/* The semaphore count was 0 and a block time was specified
1522	so configure the timeout structure ready to block. */
1523	vTaskInternalSetTimeOutState( &xTimeOut );
1524	xEntryTimeSet = pdTRUE;
1525	}
1526	else
1527	{
1528	/* Entry time was already set. */
1529	mtCOVERAGE_TEST_MARKER();
1530	}
1531	}
1532	}
1533	taskEXIT_CRITICAL();
1534
1535	/* Interrupts and other tasks can give to and take from the semaphore
1536	now the critical section has been exited. */
1537
1538	vTaskSuspendAll();
1539	prvLockQueue( pxQueue );
1540
1541	/* Update the timeout state to see if it has expired yet. */
1542	if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
1543	{
1544	/* A block time is specified and not expired. If the semaphore
1545	count is 0 then enter the Blocked state to wait for a semaphore to
1546	become available. As semaphores are implemented with queues the
1547	queue being empty is equivalent to the semaphore count being 0. */
1548	if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1549	{
1550	traceBLOCKING_ON_QUEUE_RECEIVE( pxQueue );
1551
1552	#if ( configUSE_MUTEXES == 1 )
1553	{
1554	if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
1555	{
1556	taskENTER_CRITICAL();
1557	{
1558	xInheritanceOccurred = xTaskPriorityInherit( pxQueue->u.xSemaphore.xMutexHolder );
1559	}
1560	taskEXIT_CRITICAL();
1561	}
1562	else
1563	{
1564	mtCOVERAGE_TEST_MARKER();
1565	}
1566	}
1567	#endif
1568
1569	vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
1570	prvUnlockQueue( pxQueue );
1571	if( xTaskResumeAll() == pdFALSE )
1572	{
1573	portYIELD_WITHIN_API();
1574	}
1575	else
1576	{
1577	mtCOVERAGE_TEST_MARKER();
1578	}
1579	}
1580	else
1581	{
1582	/* There was no timeout and the semaphore count was not 0, so
1583	attempt to take the semaphore again. */
1584	prvUnlockQueue( pxQueue );
1585	( void ) xTaskResumeAll();
1586	}
1587	}
1588	else
1589	{
1590	/* Timed out. */
1591	prvUnlockQueue( pxQueue );
1592	( void ) xTaskResumeAll();
1593
1594	/* If the semaphore count is 0 exit now as the timeout has
1595	expired. Otherwise return to attempt to take the semaphore that is
1596	known to be available. As semaphores are implemented by queues the
1597	queue being empty is equivalent to the semaphore count being 0. */
1598	if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1599	{
1600	#if ( configUSE_MUTEXES == 1 )
1601	{
1602	/* xInheritanceOccurred could only have be set if
1603	pxQueue->uxQueueType == queueQUEUE_IS_MUTEX so no need to
1604	test the mutex type again to check it is actually a mutex. */
1605	if( xInheritanceOccurred != pdFALSE )
1606	{
1607	taskENTER_CRITICAL();
1608	{
1609	UBaseType_t uxHighestWaitingPriority;
1610
1611	/* This task blocking on the mutex caused another
1612	task to inherit this task's priority. Now this task
1613	has timed out the priority should be disinherited
1614	again, but only as low as the next highest priority
1615	task that is waiting for the same mutex. */
1616	uxHighestWaitingPriority = prvGetDisinheritPriorityAfterTimeout( pxQueue );
1617	vTaskPriorityDisinheritAfterTimeout( pxQueue->u.xSemaphore.xMutexHolder, uxHighestWaitingPriority );
1618	}
1619	taskEXIT_CRITICAL();
1620	}
1621	}
1622	#endif /* configUSE_MUTEXES */
1623
1624	traceQUEUE_RECEIVE_FAILED( pxQueue );
1625	return errQUEUE_EMPTY;
1626	}
1627	else
1628	{
1629	mtCOVERAGE_TEST_MARKER();
1630	}
1631	}
1632	} /lint -restore /
1633	}
1634	/-----------------------------------------------------------/
1635
1636	BaseType_t xQueuePeek( QueueHandle_t xQueue, void * const pvBuffer, TickType_t xTicksToWait )
1637	{
1638	BaseType_t xEntryTimeSet = pdFALSE;
1639	TimeOut_t xTimeOut;
1640	int8_t *pcOriginalReadPosition;
1641	Queue_t * const pxQueue = xQueue;
1642
1643	/* Check the pointer is not NULL. */
1644	configASSERT( ( pxQueue ) );
1645
1646	/* The buffer into which data is received can only be NULL if the data size
1647	is zero (so no data is copied into the buffer. */
1648	configASSERT( !( ( ( pvBuffer ) == NULL ) && ( ( pxQueue )->uxItemSize != ( UBaseType_t ) 0U ) ) );
1649
1650	/* Cannot block if the scheduler is suspended. */
1651	#if ( ( INCLUDE_xTaskGetSchedulerState == 1 ) \|\| ( configUSE_TIMERS == 1 ) )
1652	{
1653	configASSERT( !( ( xTaskGetSchedulerState() == taskSCHEDULER_SUSPENDED ) && ( xTicksToWait != 0 ) ) );
1654	}
1655	#endif
1656
1657
1658	/*lint -save -e904 This function relaxes the coding standard somewhat to
1659	allow return statements within the function itself. This is done in the
1660	interest of execution time efficiency. */
1661	for( ;; )
1662	{
1663	taskENTER_CRITICAL();
1664	{
1665	const UBaseType_t uxMessagesWaiting = pxQueue->uxMessagesWaiting;
1666
1667	/* Is there data in the queue now? To be running the calling task
1668	must be the highest priority task wanting to access the queue. */
1669	if( uxMessagesWaiting > ( UBaseType_t ) 0 )
1670	{
1671	/* Remember the read position so it can be reset after the data
1672	is read from the queue as this function is only peeking the
1673	data, not removing it. */
1674	pcOriginalReadPosition = pxQueue->u.xQueue.pcReadFrom;
1675
1676	prvCopyDataFromQueue( pxQueue, pvBuffer );
1677	traceQUEUE_PEEK( pxQueue );
1678
1679	/* The data is not being removed, so reset the read pointer. */
1680	pxQueue->u.xQueue.pcReadFrom = pcOriginalReadPosition;
1681
1682	/* The data is being left in the queue, so see if there are
1683	any other tasks waiting for the data. */
1684	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
1685	{
1686	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
1687	{
1688	/* The task waiting has a higher priority than this task. */
1689	queueYIELD_IF_USING_PREEMPTION();
1690	}
1691	else
1692	{
1693	mtCOVERAGE_TEST_MARKER();
1694	}
1695	}
1696	else
1697	{
1698	mtCOVERAGE_TEST_MARKER();
1699	}
1700
1701	taskEXIT_CRITICAL();
1702	return pdPASS;
1703	}
1704	else
1705	{
1706	if( xTicksToWait == ( TickType_t ) 0 )
1707	{
1708	/* The queue was empty and no block time is specified (or
1709	the block time has expired) so leave now. */
1710	taskEXIT_CRITICAL();
1711	traceQUEUE_PEEK_FAILED( pxQueue );
1712	return errQUEUE_EMPTY;
1713	}
1714	else if( xEntryTimeSet == pdFALSE )
1715	{
1716	/* The queue was empty and a block time was specified so
1717	configure the timeout structure ready to enter the blocked
1718	state. */
1719	vTaskInternalSetTimeOutState( &xTimeOut );
1720	xEntryTimeSet = pdTRUE;
1721	}
1722	else
1723	{
1724	/* Entry time was already set. */
1725	mtCOVERAGE_TEST_MARKER();
1726	}
1727	}
1728	}
1729	taskEXIT_CRITICAL();
1730
1731	/* Interrupts and other tasks can send to and receive from the queue
1732	now the critical section has been exited. */
1733
1734	vTaskSuspendAll();
1735	prvLockQueue( pxQueue );
1736
1737	/* Update the timeout state to see if it has expired yet. */
1738	if( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE )
1739	{
1740	/* Timeout has not expired yet, check to see if there is data in the
1741	queue now, and if not enter the Blocked state to wait for data. */
1742	if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1743	{
1744	traceBLOCKING_ON_QUEUE_PEEK( pxQueue );
1745	vTaskPlaceOnEventList( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait );
1746	prvUnlockQueue( pxQueue );
1747	if( xTaskResumeAll() == pdFALSE )
1748	{
1749	portYIELD_WITHIN_API();
1750	}
1751	else
1752	{
1753	mtCOVERAGE_TEST_MARKER();
1754	}
1755	}
1756	else
1757	{
1758	/* There is data in the queue now, so don't enter the blocked
1759	state, instead return to try and obtain the data. */
1760	prvUnlockQueue( pxQueue );
1761	( void ) xTaskResumeAll();
1762	}
1763	}
1764	else
1765	{
1766	/* The timeout has expired. If there is still no data in the queue
1767	exit, otherwise go back and try to read the data again. */
1768	prvUnlockQueue( pxQueue );
1769	( void ) xTaskResumeAll();
1770
1771	if( prvIsQueueEmpty( pxQueue ) != pdFALSE )
1772	{
1773	traceQUEUE_PEEK_FAILED( pxQueue );
1774	return errQUEUE_EMPTY;
1775	}
1776	else
1777	{
1778	mtCOVERAGE_TEST_MARKER();
1779	}
1780	}
1781	} /lint -restore /
1782	}
1783	/-----------------------------------------------------------/
1784
1785	BaseType_t xQueueReceiveFromISR( QueueHandle_t xQueue, void * const pvBuffer, BaseType_t * const pxHigherPriorityTaskWoken )
1786	{
1787	BaseType_t xReturn;
1788	UBaseType_t uxSavedInterruptStatus;
1789	Queue_t * const pxQueue = xQueue;
1790
1791	configASSERT( pxQueue );
1792	configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
1793
1794	/* RTOS ports that support interrupt nesting have the concept of a maximum
1795	system call (or maximum API call) interrupt priority. Interrupts that are
1796	above the maximum system call priority are kept permanently enabled, even
1797	when the RTOS kernel is in a critical section, but cannot make any calls to
1798	FreeRTOS API functions. If configASSERT() is defined in FreeRTOSConfig.h
1799	then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
1800	failure if a FreeRTOS API function is called from an interrupt that has been
1801	assigned a priority above the configured maximum system call priority.
1802	Only FreeRTOS functions that end in FromISR can be called from interrupts
1803	that have been assigned a priority at or (logically) below the maximum
1804	system call interrupt priority. FreeRTOS maintains a separate interrupt
1805	safe API to ensure interrupt entry is as fast and as simple as possible.
1806	More information (albeit Cortex-M specific) is provided on the following
1807	link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
1808	portASSERT_IF_INTERRUPT_PRIORITY_INVALID();
1809
1810	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
1811	{
1812	const UBaseType_t uxMessagesWaiting = pxQueue->uxMessagesWaiting;
1813
1814	/* Cannot block in an ISR, so check there is data available. */
1815	if( uxMessagesWaiting > ( UBaseType_t ) 0 )
1816	{
1817	const int8_t cRxLock = pxQueue->cRxLock;
1818
1819	traceQUEUE_RECEIVE_FROM_ISR( pxQueue );
1820
1821	prvCopyDataFromQueue( pxQueue, pvBuffer );
1822	pxQueue->uxMessagesWaiting = uxMessagesWaiting - ( UBaseType_t ) 1;
1823
1824	/* If the queue is locked the event list will not be modified.
1825	Instead update the lock count so the task that unlocks the queue
1826	will know that an ISR has removed data while the queue was
1827	locked. */
1828	if( cRxLock == queueUNLOCKED )
1829	{
1830	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
1831	{
1832	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
1833	{
1834	/* The task waiting has a higher priority than us so
1835	force a context switch. */
1836	if( pxHigherPriorityTaskWoken != NULL )
1837	{
1838	*pxHigherPriorityTaskWoken = pdTRUE;
1839	}
1840	else
1841	{
1842	mtCOVERAGE_TEST_MARKER();
1843	}
1844	}
1845	else
1846	{
1847	mtCOVERAGE_TEST_MARKER();
1848	}
1849	}
1850	else
1851	{
1852	mtCOVERAGE_TEST_MARKER();
1853	}
1854	}
1855	else
1856	{
1857	/* Increment the lock count so the task that unlocks the queue
1858	knows that data was removed while it was locked. */
1859	pxQueue->cRxLock = ( int8_t ) ( cRxLock + 1 );
1860	}
1861
1862	xReturn = pdPASS;
1863	}
1864	else
1865	{
1866	xReturn = pdFAIL;
1867	traceQUEUE_RECEIVE_FROM_ISR_FAILED( pxQueue );
1868	}
1869	}
1870	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1871
1872	return xReturn;
1873	}
1874	/-----------------------------------------------------------/
1875
1876	BaseType_t xQueuePeekFromISR( QueueHandle_t xQueue, void * const pvBuffer )
1877	{
1878	BaseType_t xReturn;
1879	UBaseType_t uxSavedInterruptStatus;
1880	int8_t *pcOriginalReadPosition;
1881	Queue_t * const pxQueue = xQueue;
1882
1883	configASSERT( pxQueue );
1884	configASSERT( !( ( pvBuffer == NULL ) && ( pxQueue->uxItemSize != ( UBaseType_t ) 0U ) ) );
1885	configASSERT( pxQueue->uxItemSize != 0 ); /* Can't peek a semaphore. */
1886
1887	/* RTOS ports that support interrupt nesting have the concept of a maximum
1888	system call (or maximum API call) interrupt priority. Interrupts that are
1889	above the maximum system call priority are kept permanently enabled, even
1890	when the RTOS kernel is in a critical section, but cannot make any calls to
1891	FreeRTOS API functions. If configASSERT() is defined in FreeRTOSConfig.h
1892	then portASSERT_IF_INTERRUPT_PRIORITY_INVALID() will result in an assertion
1893	failure if a FreeRTOS API function is called from an interrupt that has been
1894	assigned a priority above the configured maximum system call priority.
1895	Only FreeRTOS functions that end in FromISR can be called from interrupts
1896	that have been assigned a priority at or (logically) below the maximum
1897	system call interrupt priority. FreeRTOS maintains a separate interrupt
1898	safe API to ensure interrupt entry is as fast and as simple as possible.
1899	More information (albeit Cortex-M specific) is provided on the following
1900	link: http://www.freertos.org/RTOS-Cortex-M3-M4.html */
1901	portASSERT_IF_INTERRUPT_PRIORITY_INVALID();
1902
1903	uxSavedInterruptStatus = portSET_INTERRUPT_MASK_FROM_ISR();
1904	{
1905	/* Cannot block in an ISR, so check there is data available. */
1906	if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
1907	{
1908	traceQUEUE_PEEK_FROM_ISR( pxQueue );
1909
1910	/* Remember the read position so it can be reset as nothing is
1911	actually being removed from the queue. */
1912	pcOriginalReadPosition = pxQueue->u.xQueue.pcReadFrom;
1913	prvCopyDataFromQueue( pxQueue, pvBuffer );
1914	pxQueue->u.xQueue.pcReadFrom = pcOriginalReadPosition;
1915
1916	xReturn = pdPASS;
1917	}
1918	else
1919	{
1920	xReturn = pdFAIL;
1921	traceQUEUE_PEEK_FROM_ISR_FAILED( pxQueue );
1922	}
1923	}
1924	portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedInterruptStatus );
1925
1926	return xReturn;
1927	}
1928	/-----------------------------------------------------------/
1929
1930	UBaseType_t uxQueueMessagesWaiting( const QueueHandle_t xQueue )
1931	{
1932	UBaseType_t uxReturn;
1933
1934	configASSERT( xQueue );
1935
1936	taskENTER_CRITICAL();
1937	{
1938	uxReturn = ( ( Queue_t * ) xQueue )->uxMessagesWaiting;
1939	}
1940	taskEXIT_CRITICAL();
1941
1942	return uxReturn;
1943	} /lint !e818 Pointer cannot be declared const as xQueue is a typedef not pointer. /
1944	/-----------------------------------------------------------/
1945
1946	UBaseType_t uxQueueSpacesAvailable( const QueueHandle_t xQueue )
1947	{
1948	UBaseType_t uxReturn;
1949	Queue_t * const pxQueue = xQueue;
1950
1951	configASSERT( pxQueue );
1952
1953	taskENTER_CRITICAL();
1954	{
1955	uxReturn = pxQueue->uxLength - pxQueue->uxMessagesWaiting;
1956	}
1957	taskEXIT_CRITICAL();
1958
1959	return uxReturn;
1960	} /lint !e818 Pointer cannot be declared const as xQueue is a typedef not pointer. /
1961	/-----------------------------------------------------------/
1962
1963	UBaseType_t uxQueueMessagesWaitingFromISR( const QueueHandle_t xQueue )
1964	{
1965	UBaseType_t uxReturn;
1966	Queue_t * const pxQueue = xQueue;
1967
1968	configASSERT( pxQueue );
1969	uxReturn = pxQueue->uxMessagesWaiting;
1970
1971	return uxReturn;
1972	} /lint !e818 Pointer cannot be declared const as xQueue is a typedef not pointer. /
1973	/-----------------------------------------------------------/
1974
1975	void vQueueDelete( QueueHandle_t xQueue )
1976	{
1977	Queue_t * const pxQueue = xQueue;
1978
1979	configASSERT( pxQueue );
1980	traceQUEUE_DELETE( pxQueue );
1981
1982	#if ( configQUEUE_REGISTRY_SIZE > 0 )
1983	{
1984	vQueueUnregisterQueue( pxQueue );
1985	}
1986	#endif
1987
1988	#if( ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 0 ) )
1989	{
1990	/* The queue can only have been allocated dynamically - free it
1991	again. */
1992	vPortFree( pxQueue );
1993	}
1994	#elif( ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 1 ) )
1995	{
1996	/* The queue could have been allocated statically or dynamically, so
1997	check before attempting to free the memory. */
1998	if( pxQueue->ucStaticallyAllocated == ( uint8_t ) pdFALSE )
1999	{
2000	vPortFree( pxQueue );
2001	}
2002	else
2003	{
2004	mtCOVERAGE_TEST_MARKER();
2005	}
2006	}
2007	#else
2008	{
2009	/* The queue must have been statically allocated, so is not going to be
2010	deleted. Avoid compiler warnings about the unused parameter. */
2011	( void ) pxQueue;
2012	}
2013	#endif /* configSUPPORT_DYNAMIC_ALLOCATION */
2014	}
2015	/-----------------------------------------------------------/
2016
2017	#if ( configUSE_TRACE_FACILITY == 1 )
2018
2019	UBaseType_t uxQueueGetQueueNumber( QueueHandle_t xQueue )
2020	{
2021	return ( ( Queue_t * ) xQueue )->uxQueueNumber;
2022	}
2023
2024	#endif /* configUSE_TRACE_FACILITY */
2025	/-----------------------------------------------------------/
2026
2027	#if ( configUSE_TRACE_FACILITY == 1 )
2028
2029	void vQueueSetQueueNumber( QueueHandle_t xQueue, UBaseType_t uxQueueNumber )
2030	{
2031	( ( Queue_t * ) xQueue )->uxQueueNumber = uxQueueNumber;
2032	}
2033
2034	#endif /* configUSE_TRACE_FACILITY */
2035	/-----------------------------------------------------------/
2036
2037	#if ( configUSE_TRACE_FACILITY == 1 )
2038
2039	uint8_t ucQueueGetQueueType( QueueHandle_t xQueue )
2040	{
2041	return ( ( Queue_t * ) xQueue )->ucQueueType;
2042	}
2043
2044	#endif /* configUSE_TRACE_FACILITY */
2045	/-----------------------------------------------------------/
2046
2047	#if( configUSE_MUTEXES == 1 )
2048
2049	static UBaseType_t prvGetDisinheritPriorityAfterTimeout( const Queue_t * const pxQueue )
2050	{
2051	UBaseType_t uxHighestPriorityOfWaitingTasks;
2052
2053	/* If a task waiting for a mutex causes the mutex holder to inherit a
2054	priority, but the waiting task times out, then the holder should
2055	disinherit the priority - but only down to the highest priority of any
2056	other tasks that are waiting for the same mutex. For this purpose,
2057	return the priority of the highest priority task that is waiting for the
2058	mutex. */
2059	if( listCURRENT_LIST_LENGTH( &( pxQueue->xTasksWaitingToReceive ) ) > 0U )
2060	{
2061	uxHighestPriorityOfWaitingTasks = ( UBaseType_t ) configMAX_PRIORITIES - ( UBaseType_t ) listGET_ITEM_VALUE_OF_HEAD_ENTRY( &( pxQueue->xTasksWaitingToReceive ) );
2062	}
2063	else
2064	{
2065	uxHighestPriorityOfWaitingTasks = tskIDLE_PRIORITY;
2066	}
2067
2068	return uxHighestPriorityOfWaitingTasks;
2069	}
2070
2071	#endif /* configUSE_MUTEXES */
2072	/-----------------------------------------------------------/
2073
2074	static BaseType_t prvCopyDataToQueue( Queue_t * const pxQueue, const void *pvItemToQueue, const BaseType_t xPosition )
2075	{
2076	BaseType_t xReturn = pdFALSE;
2077	UBaseType_t uxMessagesWaiting;
2078
2079	/* This function is called from a critical section. */
2080
2081	uxMessagesWaiting = pxQueue->uxMessagesWaiting;
2082
2083	if( pxQueue->uxItemSize == ( UBaseType_t ) 0 )
2084	{
2085	#if ( configUSE_MUTEXES == 1 )
2086	{
2087	if( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX )
2088	{
2089	/* The mutex is no longer being held. */
2090	xReturn = xTaskPriorityDisinherit( pxQueue->u.xSemaphore.xMutexHolder );
2091	pxQueue->u.xSemaphore.xMutexHolder = NULL;
2092	}
2093	else
2094	{
2095	mtCOVERAGE_TEST_MARKER();
2096	}
2097	}
2098	#endif /* configUSE_MUTEXES */
2099	}
2100	else if( xPosition == queueSEND_TO_BACK )
2101	{
2102	( void ) memcpy( ( void * ) pxQueue->pcWriteTo, pvItemToQueue, ( size_t ) pxQueue->uxItemSize ); /lint !e961 !e418 !e9087 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. Cast to void required by function signature and safe as no alignment requirement and copy length specified in bytes. /
2103	pxQueue->pcWriteTo += pxQueue->uxItemSize; /lint !e9016 Pointer arithmetic on char types ok, especially in this use case where it is the clearest way of conveying intent. /
2104	if( pxQueue->pcWriteTo >= pxQueue->u.xQueue.pcTail ) /lint !e946 MISRA exception justified as comparison of pointers is the cleanest solution. /
2105	{
2106	pxQueue->pcWriteTo = pxQueue->pcHead;
2107	}
2108	else
2109	{
2110	mtCOVERAGE_TEST_MARKER();
2111	}
2112	}
2113	else
2114	{
2115	( void ) memcpy( ( void * ) pxQueue->u.xQueue.pcReadFrom, pvItemToQueue, ( size_t ) pxQueue->uxItemSize ); /lint !e961 !e9087 !e418 MISRA exception as the casts are only redundant for some ports. Cast to void required by function signature and safe as no alignment requirement and copy length specified in bytes. Assert checks null pointer only used when length is 0. /
2116	pxQueue->u.xQueue.pcReadFrom -= pxQueue->uxItemSize;
2117	if( pxQueue->u.xQueue.pcReadFrom < pxQueue->pcHead ) /lint !e946 MISRA exception justified as comparison of pointers is the cleanest solution. /
2118	{
2119	pxQueue->u.xQueue.pcReadFrom = ( pxQueue->u.xQueue.pcTail - pxQueue->uxItemSize );
2120	}
2121	else
2122	{
2123	mtCOVERAGE_TEST_MARKER();
2124	}
2125
2126	if( xPosition == queueOVERWRITE )
2127	{
2128	if( uxMessagesWaiting > ( UBaseType_t ) 0 )
2129	{
2130	/* An item is not being added but overwritten, so subtract
2131	one from the recorded number of items in the queue so when
2132	one is added again below the number of recorded items remains
2133	correct. */
2134	--uxMessagesWaiting;
2135	}
2136	else
2137	{
2138	mtCOVERAGE_TEST_MARKER();
2139	}
2140	}
2141	else
2142	{
2143	mtCOVERAGE_TEST_MARKER();
2144	}
2145	}
2146
2147	pxQueue->uxMessagesWaiting = uxMessagesWaiting + ( UBaseType_t ) 1;
2148
2149	return xReturn;
2150	}
2151	/-----------------------------------------------------------/
2152
2153	static void prvCopyDataFromQueue( Queue_t * const pxQueue, void * const pvBuffer )
2154	{
2155	if( pxQueue->uxItemSize != ( UBaseType_t ) 0 )
2156	{
2157	pxQueue->u.xQueue.pcReadFrom += pxQueue->uxItemSize; /lint !e9016 Pointer arithmetic on char types ok, especially in this use case where it is the clearest way of conveying intent. /
2158	if( pxQueue->u.xQueue.pcReadFrom >= pxQueue->u.xQueue.pcTail ) /lint !e946 MISRA exception justified as use of the relational operator is the cleanest solutions. /
2159	{
2160	pxQueue->u.xQueue.pcReadFrom = pxQueue->pcHead;
2161	}
2162	else
2163	{
2164	mtCOVERAGE_TEST_MARKER();
2165	}
2166	( void ) memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.xQueue.pcReadFrom, ( size_t ) pxQueue->uxItemSize ); /lint !e961 !e418 !e9087 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. Cast to void required by function signature and safe as no alignment requirement and copy length specified in bytes. /
2167	}
2168	}
2169	/-----------------------------------------------------------/
2170
2171	static void prvUnlockQueue( Queue_t * const pxQueue )
2172	{
2173	/* THIS FUNCTION MUST BE CALLED WITH THE SCHEDULER SUSPENDED. */
2174
2175	/* The lock counts contains the number of extra data items placed or
2176	removed from the queue while the queue was locked. When a queue is
2177	locked items can be added or removed, but the event lists cannot be
2178	updated. */
2179	taskENTER_CRITICAL();
2180	{
2181	int8_t cTxLock = pxQueue->cTxLock;
2182
2183	/* See if data was added to the queue while it was locked. */
2184	while( cTxLock > queueLOCKED_UNMODIFIED )
2185	{
2186	/* Data was posted while the queue was locked. Are any tasks
2187	blocked waiting for data to become available? */
2188	#if ( configUSE_QUEUE_SETS == 1 )
2189	{
2190	if( pxQueue->pxQueueSetContainer != NULL )
2191	{
2192	if( prvNotifyQueueSetContainer( pxQueue ) != pdFALSE )
2193	{
2194	/* The queue is a member of a queue set, and posting to
2195	the queue set caused a higher priority task to unblock.
2196	A context switch is required. */
2197	vTaskMissedYield();
2198	}
2199	else
2200	{
2201	mtCOVERAGE_TEST_MARKER();
2202	}
2203	}
2204	else
2205	{
2206	/* Tasks that are removed from the event list will get
2207	added to the pending ready list as the scheduler is still
2208	suspended. */
2209	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
2210	{
2211	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
2212	{
2213	/* The task waiting has a higher priority so record that a
2214	context switch is required. */
2215	vTaskMissedYield();
2216	}
2217	else
2218	{
2219	mtCOVERAGE_TEST_MARKER();
2220	}
2221	}
2222	else
2223	{
2224	break;
2225	}
2226	}
2227	}
2228	#else /* configUSE_QUEUE_SETS */
2229	{
2230	/* Tasks that are removed from the event list will get added to
2231	the pending ready list as the scheduler is still suspended. */
2232	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
2233	{
2234	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
2235	{
2236	/* The task waiting has a higher priority so record that
2237	a context switch is required. */
2238	vTaskMissedYield();
2239	}
2240	else
2241	{
2242	mtCOVERAGE_TEST_MARKER();
2243	}
2244	}
2245	else
2246	{
2247	break;
2248	}
2249	}
2250	#endif /* configUSE_QUEUE_SETS */
2251
2252	--cTxLock;
2253	}
2254
2255	pxQueue->cTxLock = queueUNLOCKED;
2256	}
2257	taskEXIT_CRITICAL();
2258
2259	/* Do the same for the Rx lock. */
2260	taskENTER_CRITICAL();
2261	{
2262	int8_t cRxLock = pxQueue->cRxLock;
2263
2264	while( cRxLock > queueLOCKED_UNMODIFIED )
2265	{
2266	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
2267	{
2268	if( xTaskRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
2269	{
2270	vTaskMissedYield();
2271	}
2272	else
2273	{
2274	mtCOVERAGE_TEST_MARKER();
2275	}
2276
2277	--cRxLock;
2278	}
2279	else
2280	{
2281	break;
2282	}
2283	}
2284
2285	pxQueue->cRxLock = queueUNLOCKED;
2286	}
2287	taskEXIT_CRITICAL();
2288	}
2289	/-----------------------------------------------------------/
2290
2291	static BaseType_t prvIsQueueEmpty( const Queue_t *pxQueue )
2292	{
2293	BaseType_t xReturn;
2294
2295	taskENTER_CRITICAL();
2296	{
2297	if( pxQueue->uxMessagesWaiting == ( UBaseType_t ) 0 )
2298	{
2299	xReturn = pdTRUE;
2300	}
2301	else
2302	{
2303	xReturn = pdFALSE;
2304	}
2305	}
2306	taskEXIT_CRITICAL();
2307
2308	return xReturn;
2309	}
2310	/-----------------------------------------------------------/
2311
2312	BaseType_t xQueueIsQueueEmptyFromISR( const QueueHandle_t xQueue )
2313	{
2314	BaseType_t xReturn;
2315	Queue_t * const pxQueue = xQueue;
2316
2317	configASSERT( pxQueue );
2318	if( pxQueue->uxMessagesWaiting == ( UBaseType_t ) 0 )
2319	{
2320	xReturn = pdTRUE;
2321	}
2322	else
2323	{
2324	xReturn = pdFALSE;
2325	}
2326
2327	return xReturn;
2328	} /lint !e818 xQueue could not be pointer to const because it is a typedef. /
2329	/-----------------------------------------------------------/
2330
2331	static BaseType_t prvIsQueueFull( const Queue_t *pxQueue )
2332	{
2333	BaseType_t xReturn;
2334
2335	taskENTER_CRITICAL();
2336	{
2337	if( pxQueue->uxMessagesWaiting == pxQueue->uxLength )
2338	{
2339	xReturn = pdTRUE;
2340	}
2341	else
2342	{
2343	xReturn = pdFALSE;
2344	}
2345	}
2346	taskEXIT_CRITICAL();
2347
2348	return xReturn;
2349	}
2350	/-----------------------------------------------------------/
2351
2352	BaseType_t xQueueIsQueueFullFromISR( const QueueHandle_t xQueue )
2353	{
2354	BaseType_t xReturn;
2355	Queue_t * const pxQueue = xQueue;
2356
2357	configASSERT( pxQueue );
2358	if( pxQueue->uxMessagesWaiting == pxQueue->uxLength )
2359	{
2360	xReturn = pdTRUE;
2361	}
2362	else
2363	{
2364	xReturn = pdFALSE;
2365	}
2366
2367	return xReturn;
2368	} /lint !e818 xQueue could not be pointer to const because it is a typedef. /
2369	/-----------------------------------------------------------/
2370
2371	#if ( configUSE_CO_ROUTINES == 1 )
2372
2373	BaseType_t xQueueCRSend( QueueHandle_t xQueue, const void *pvItemToQueue, TickType_t xTicksToWait )
2374	{
2375	BaseType_t xReturn;
2376	Queue_t * const pxQueue = xQueue;
2377
2378	/* If the queue is already full we may have to block. A critical section
2379	is required to prevent an interrupt removing something from the queue
2380	between the check to see if the queue is full and blocking on the queue. */
2381	portDISABLE_INTERRUPTS();
2382	{
2383	if( prvIsQueueFull( pxQueue ) != pdFALSE )
2384	{
2385	/* The queue is full - do we want to block or just leave without
2386	posting? */
2387	if( xTicksToWait > ( TickType_t ) 0 )
2388	{
2389	/* As this is called from a coroutine we cannot block directly, but
2390	return indicating that we need to block. */
2391	vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToSend ) );
2392	portENABLE_INTERRUPTS();
2393	return errQUEUE_BLOCKED;
2394	}
2395	else
2396	{
2397	portENABLE_INTERRUPTS();
2398	return errQUEUE_FULL;
2399	}
2400	}
2401	}
2402	portENABLE_INTERRUPTS();
2403
2404	portDISABLE_INTERRUPTS();
2405	{
2406	if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
2407	{
2408	/* There is room in the queue, copy the data into the queue. */
2409	prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );
2410	xReturn = pdPASS;
2411
2412	/* Were any co-routines waiting for data to become available? */
2413	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
2414	{
2415	/* In this instance the co-routine could be placed directly
2416	into the ready list as we are within a critical section.
2417	Instead the same pending ready list mechanism is used as if
2418	the event were caused from within an interrupt. */
2419	if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
2420	{
2421	/* The co-routine waiting has a higher priority so record
2422	that a yield might be appropriate. */
2423	xReturn = errQUEUE_YIELD;
2424	}
2425	else
2426	{
2427	mtCOVERAGE_TEST_MARKER();
2428	}
2429	}
2430	else
2431	{
2432	mtCOVERAGE_TEST_MARKER();
2433	}
2434	}
2435	else
2436	{
2437	xReturn = errQUEUE_FULL;
2438	}
2439	}
2440	portENABLE_INTERRUPTS();
2441
2442	return xReturn;
2443	}
2444
2445	#endif /* configUSE_CO_ROUTINES */
2446	/-----------------------------------------------------------/
2447
2448	#if ( configUSE_CO_ROUTINES == 1 )
2449
2450	BaseType_t xQueueCRReceive( QueueHandle_t xQueue, void *pvBuffer, TickType_t xTicksToWait )
2451	{
2452	BaseType_t xReturn;
2453	Queue_t * const pxQueue = xQueue;
2454
2455	/* If the queue is already empty we may have to block. A critical section
2456	is required to prevent an interrupt adding something to the queue
2457	between the check to see if the queue is empty and blocking on the queue. */
2458	portDISABLE_INTERRUPTS();
2459	{
2460	if( pxQueue->uxMessagesWaiting == ( UBaseType_t ) 0 )
2461	{
2462	/* There are no messages in the queue, do we want to block or just
2463	leave with nothing? */
2464	if( xTicksToWait > ( TickType_t ) 0 )
2465	{
2466	/* As this is a co-routine we cannot block directly, but return
2467	indicating that we need to block. */
2468	vCoRoutineAddToDelayedList( xTicksToWait, &( pxQueue->xTasksWaitingToReceive ) );
2469	portENABLE_INTERRUPTS();
2470	return errQUEUE_BLOCKED;
2471	}
2472	else
2473	{
2474	portENABLE_INTERRUPTS();
2475	return errQUEUE_FULL;
2476	}
2477	}
2478	else
2479	{
2480	mtCOVERAGE_TEST_MARKER();
2481	}
2482	}
2483	portENABLE_INTERRUPTS();
2484
2485	portDISABLE_INTERRUPTS();
2486	{
2487	if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
2488	{
2489	/* Data is available from the queue. */
2490	pxQueue->u.xQueue.pcReadFrom += pxQueue->uxItemSize;
2491	if( pxQueue->u.xQueue.pcReadFrom >= pxQueue->u.xQueue.pcTail )
2492	{
2493	pxQueue->u.xQueue.pcReadFrom = pxQueue->pcHead;
2494	}
2495	else
2496	{
2497	mtCOVERAGE_TEST_MARKER();
2498	}
2499	--( pxQueue->uxMessagesWaiting );
2500	( void ) memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.xQueue.pcReadFrom, ( unsigned ) pxQueue->uxItemSize );
2501
2502	xReturn = pdPASS;
2503
2504	/* Were any co-routines waiting for space to become available? */
2505	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
2506	{
2507	/* In this instance the co-routine could be placed directly
2508	into the ready list as we are within a critical section.
2509	Instead the same pending ready list mechanism is used as if
2510	the event were caused from within an interrupt. */
2511	if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
2512	{
2513	xReturn = errQUEUE_YIELD;
2514	}
2515	else
2516	{
2517	mtCOVERAGE_TEST_MARKER();
2518	}
2519	}
2520	else
2521	{
2522	mtCOVERAGE_TEST_MARKER();
2523	}
2524	}
2525	else
2526	{
2527	xReturn = pdFAIL;
2528	}
2529	}
2530	portENABLE_INTERRUPTS();
2531
2532	return xReturn;
2533	}
2534
2535	#endif /* configUSE_CO_ROUTINES */
2536	/-----------------------------------------------------------/
2537
2538	#if ( configUSE_CO_ROUTINES == 1 )
2539
2540	BaseType_t xQueueCRSendFromISR( QueueHandle_t xQueue, const void *pvItemToQueue, BaseType_t xCoRoutinePreviouslyWoken )
2541	{
2542	Queue_t * const pxQueue = xQueue;
2543
2544	/* Cannot block within an ISR so if there is no space on the queue then
2545	exit without doing anything. */
2546	if( pxQueue->uxMessagesWaiting < pxQueue->uxLength )
2547	{
2548	prvCopyDataToQueue( pxQueue, pvItemToQueue, queueSEND_TO_BACK );
2549
2550	/* We only want to wake one co-routine per ISR, so check that a
2551	co-routine has not already been woken. */
2552	if( xCoRoutinePreviouslyWoken == pdFALSE )
2553	{
2554	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToReceive ) ) == pdFALSE )
2555	{
2556	if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToReceive ) ) != pdFALSE )
2557	{
2558	return pdTRUE;
2559	}
2560	else
2561	{
2562	mtCOVERAGE_TEST_MARKER();
2563	}
2564	}
2565	else
2566	{
2567	mtCOVERAGE_TEST_MARKER();
2568	}
2569	}
2570	else
2571	{
2572	mtCOVERAGE_TEST_MARKER();
2573	}
2574	}
2575	else
2576	{
2577	mtCOVERAGE_TEST_MARKER();
2578	}
2579
2580	return xCoRoutinePreviouslyWoken;
2581	}
2582
2583	#endif /* configUSE_CO_ROUTINES */
2584	/-----------------------------------------------------------/
2585
2586	#if ( configUSE_CO_ROUTINES == 1 )
2587
2588	BaseType_t xQueueCRReceiveFromISR( QueueHandle_t xQueue, void pvBuffer, BaseType_t pxCoRoutineWoken )
2589	{
2590	BaseType_t xReturn;
2591	Queue_t * const pxQueue = xQueue;
2592
2593	/* We cannot block from an ISR, so check there is data available. If
2594	not then just leave without doing anything. */
2595	if( pxQueue->uxMessagesWaiting > ( UBaseType_t ) 0 )
2596	{
2597	/* Copy the data from the queue. */
2598	pxQueue->u.xQueue.pcReadFrom += pxQueue->uxItemSize;
2599	if( pxQueue->u.xQueue.pcReadFrom >= pxQueue->u.xQueue.pcTail )
2600	{
2601	pxQueue->u.xQueue.pcReadFrom = pxQueue->pcHead;
2602	}
2603	else
2604	{
2605	mtCOVERAGE_TEST_MARKER();
2606	}
2607	--( pxQueue->uxMessagesWaiting );
2608	( void ) memcpy( ( void * ) pvBuffer, ( void * ) pxQueue->u.xQueue.pcReadFrom, ( unsigned ) pxQueue->uxItemSize );
2609
2610	if( ( *pxCoRoutineWoken ) == pdFALSE )
2611	{
2612	if( listLIST_IS_EMPTY( &( pxQueue->xTasksWaitingToSend ) ) == pdFALSE )
2613	{
2614	if( xCoRoutineRemoveFromEventList( &( pxQueue->xTasksWaitingToSend ) ) != pdFALSE )
2615	{
2616	*pxCoRoutineWoken = pdTRUE;
2617	}
2618	else
2619	{
2620	mtCOVERAGE_TEST_MARKER();
2621	}
2622	}
2623	else
2624	{
2625	mtCOVERAGE_TEST_MARKER();
2626	}
2627	}
2628	else
2629	{
2630	mtCOVERAGE_TEST_MARKER();
2631	}
2632
2633	xReturn = pdPASS;
2634	}
2635	else
2636	{
2637	xReturn = pdFAIL;
2638	}
2639
2640	return xReturn;
2641	}
2642
2643	#endif /* configUSE_CO_ROUTINES */
2644	/-----------------------------------------------------------/
2645
2646	#if ( configQUEUE_REGISTRY_SIZE > 0 )
2647
2648	void vQueueAddToRegistry( QueueHandle_t xQueue, const char pcQueueName ) /lint !e971 Unqualified char types are allowed for strings and single characters only. */
2649	{
2650	UBaseType_t ux;
2651
2652	/* See if there is an empty space in the registry. A NULL name denotes
2653	a free slot. */
2654	for( ux = ( UBaseType_t ) 0U; ux < ( UBaseType_t ) configQUEUE_REGISTRY_SIZE; ux++ )
2655	{
2656	if( xQueueRegistry[ ux ].pcQueueName == NULL )
2657	{
2658	/* Store the information on this queue. */
2659	xQueueRegistry[ ux ].pcQueueName = pcQueueName;
2660	xQueueRegistry[ ux ].xHandle = xQueue;
2661
2662	traceQUEUE_REGISTRY_ADD( xQueue, pcQueueName );
2663	break;
2664	}
2665	else
2666	{
2667	mtCOVERAGE_TEST_MARKER();
2668	}
2669	}
2670	}
2671
2672	#endif /* configQUEUE_REGISTRY_SIZE */
2673	/-----------------------------------------------------------/
2674
2675	#if ( configQUEUE_REGISTRY_SIZE > 0 )
2676
2677	const char pcQueueGetName( QueueHandle_t xQueue ) /lint !e971 Unqualified char types are allowed for strings and single characters only. */
2678	{
2679	UBaseType_t ux;
2680	const char pcReturn = NULL; /lint !e971 Unqualified char types are allowed for strings and single characters only. */
2681
2682	/* Note there is nothing here to protect against another task adding or
2683	removing entries from the registry while it is being searched. */
2684	for( ux = ( UBaseType_t ) 0U; ux < ( UBaseType_t ) configQUEUE_REGISTRY_SIZE; ux++ )
2685	{
2686	if( xQueueRegistry[ ux ].xHandle == xQueue )
2687	{
2688	pcReturn = xQueueRegistry[ ux ].pcQueueName;
2689	break;
2690	}
2691	else
2692	{
2693	mtCOVERAGE_TEST_MARKER();
2694	}
2695	}
2696
2697	return pcReturn;
2698	} /lint !e818 xQueue cannot be a pointer to const because it is a typedef. /
2699
2700	#endif /* configQUEUE_REGISTRY_SIZE */
2701	/-----------------------------------------------------------/
2702
2703	#if ( configQUEUE_REGISTRY_SIZE > 0 )
2704
2705	void vQueueUnregisterQueue( QueueHandle_t xQueue )
2706	{
2707	UBaseType_t ux;
2708
2709	/* See if the handle of the queue being unregistered in actually in the
2710	registry. */
2711	for( ux = ( UBaseType_t ) 0U; ux < ( UBaseType_t ) configQUEUE_REGISTRY_SIZE; ux++ )
2712	{
2713	if( xQueueRegistry[ ux ].xHandle == xQueue )
2714	{
2715	/* Set the name to NULL to show that this slot if free again. */
2716	xQueueRegistry[ ux ].pcQueueName = NULL;
2717
2718	/* Set the handle to NULL to ensure the same queue handle cannot
2719	appear in the registry twice if it is added, removed, then
2720	added again. */
2721	xQueueRegistry[ ux ].xHandle = ( QueueHandle_t ) 0;
2722	break;
2723	}
2724	else
2725	{
2726	mtCOVERAGE_TEST_MARKER();
2727	}
2728	}
2729
2730	} /lint !e818 xQueue could not be pointer to const because it is a typedef. /
2731
2732	#endif /* configQUEUE_REGISTRY_SIZE */
2733	/-----------------------------------------------------------/
2734
2735	#if ( configUSE_TIMERS == 1 )
2736
2737	void vQueueWaitForMessageRestricted( QueueHandle_t xQueue, TickType_t xTicksToWait, const BaseType_t xWaitIndefinitely )
2738	{
2739	Queue_t * const pxQueue = xQueue;
2740
2741	/* This function should not be called by application code hence the
2742	'Restricted' in its name. It is not part of the public API. It is
2743	designed for use by kernel code, and has special calling requirements.
2744	It can result in vListInsert() being called on a list that can only
2745	possibly ever have one item in it, so the list will be fast, but even
2746	so it should be called with the scheduler locked and not from a critical
2747	section. */
2748
2749	/* Only do anything if there are no messages in the queue. This function
2750	will not actually cause the task to block, just place it on a blocked
2751	list. It will not block until the scheduler is unlocked - at which
2752	time a yield will be performed. If an item is added to the queue while
2753	the queue is locked, and the calling task blocks on the queue, then the
2754	calling task will be immediately unblocked when the queue is unlocked. */
2755	prvLockQueue( pxQueue );
2756	if( pxQueue->uxMessagesWaiting == ( UBaseType_t ) 0U )
2757	{
2758	/* There is nothing in the queue, block for the specified period. */
2759	vTaskPlaceOnEventListRestricted( &( pxQueue->xTasksWaitingToReceive ), xTicksToWait, xWaitIndefinitely );
2760	}
2761	else
2762	{
2763	mtCOVERAGE_TEST_MARKER();
2764	}
2765	prvUnlockQueue( pxQueue );
2766	}
2767
2768	#endif /* configUSE_TIMERS */
2769	/-----------------------------------------------------------/
2770
2771	#if( ( configUSE_QUEUE_SETS == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
2772
2773	QueueSetHandle_t xQueueCreateSet( const UBaseType_t uxEventQueueLength )
2774	{
2775	QueueSetHandle_t pxQueue;
2776
2777	pxQueue = xQueueGenericCreate( uxEventQueueLength, ( UBaseType_t ) sizeof( Queue_t * ), queueQUEUE_TYPE_SET );
2778
2779	return pxQueue;
2780	}
2781
2782	#endif /* configUSE_QUEUE_SETS */
2783	/-----------------------------------------------------------/
2784
2785	#if ( configUSE_QUEUE_SETS == 1 )
2786
2787	BaseType_t xQueueAddToSet( QueueSetMemberHandle_t xQueueOrSemaphore, QueueSetHandle_t xQueueSet )
2788	{
2789	BaseType_t xReturn;
2790
2791	taskENTER_CRITICAL();
2792	{
2793	if( ( ( Queue_t * ) xQueueOrSemaphore )->pxQueueSetContainer != NULL )
2794	{
2795	/* Cannot add a queue/semaphore to more than one queue set. */
2796	xReturn = pdFAIL;
2797	}
2798	else if( ( ( Queue_t * ) xQueueOrSemaphore )->uxMessagesWaiting != ( UBaseType_t ) 0 )
2799	{
2800	/* Cannot add a queue/semaphore to a queue set if there are already
2801	items in the queue/semaphore. */
2802	xReturn = pdFAIL;
2803	}
2804	else
2805	{
2806	( ( Queue_t * ) xQueueOrSemaphore )->pxQueueSetContainer = xQueueSet;
2807	xReturn = pdPASS;
2808	}
2809	}
2810	taskEXIT_CRITICAL();
2811
2812	return xReturn;
2813	}
2814
2815	#endif /* configUSE_QUEUE_SETS */
2816	/-----------------------------------------------------------/
2817
2818	#if ( configUSE_QUEUE_SETS == 1 )
2819
2820	BaseType_t xQueueRemoveFromSet( QueueSetMemberHandle_t xQueueOrSemaphore, QueueSetHandle_t xQueueSet )
2821	{
2822	BaseType_t xReturn;
2823	Queue_t * const pxQueueOrSemaphore = ( Queue_t * ) xQueueOrSemaphore;
2824
2825	if( pxQueueOrSemaphore->pxQueueSetContainer != xQueueSet )
2826	{
2827	/* The queue was not a member of the set. */
2828	xReturn = pdFAIL;
2829	}
2830	else if( pxQueueOrSemaphore->uxMessagesWaiting != ( UBaseType_t ) 0 )
2831	{
2832	/* It is dangerous to remove a queue from a set when the queue is
2833	not empty because the queue set will still hold pending events for
2834	the queue. */
2835	xReturn = pdFAIL;
2836	}
2837	else
2838	{
2839	taskENTER_CRITICAL();
2840	{
2841	/* The queue is no longer contained in the set. */
2842	pxQueueOrSemaphore->pxQueueSetContainer = NULL;
2843	}
2844	taskEXIT_CRITICAL();
2845	xReturn = pdPASS;
2846	}
2847
2848	return xReturn;
2849	} /lint !e818 xQueueSet could not be declared as pointing to const as it is a typedef. /
2850
2851	#endif /* configUSE_QUEUE_SETS */
2852	/-----------------------------------------------------------/
2853
2854	#if ( configUSE_QUEUE_SETS == 1 )
2855
2856	QueueSetMemberHandle_t xQueueSelectFromSet( QueueSetHandle_t xQueueSet, TickType_t const xTicksToWait )
2857	{
2858	QueueSetMemberHandle_t xReturn = NULL;
2859
2860	( void ) xQueueReceive( ( QueueHandle_t ) xQueueSet, &xReturn, xTicksToWait ); /lint !e961 Casting from one typedef to another is not redundant. /
2861	return xReturn;
2862	}
2863
2864	#endif /* configUSE_QUEUE_SETS */
2865	/-----------------------------------------------------------/
2866
2867	#if ( configUSE_QUEUE_SETS == 1 )
2868
2869	QueueSetMemberHandle_t xQueueSelectFromSetFromISR( QueueSetHandle_t xQueueSet )
2870	{
2871	QueueSetMemberHandle_t xReturn = NULL;
2872
2873	( void ) xQueueReceiveFromISR( ( QueueHandle_t ) xQueueSet, &xReturn, NULL ); /lint !e961 Casting from one typedef to another is not redundant. /
2874	return xReturn;
2875	}
2876
2877	#endif /* configUSE_QUEUE_SETS */
2878	/-----------------------------------------------------------/
2879
2880	#if ( configUSE_QUEUE_SETS == 1 )
2881
2882	static BaseType_t prvNotifyQueueSetContainer( const Queue_t * const pxQueue )
2883	{
2884	Queue_t *pxQueueSetContainer = pxQueue->pxQueueSetContainer;
2885	BaseType_t xReturn = pdFALSE;
2886
2887	/* This function must be called form a critical section. */
2888
2889	configASSERT( pxQueueSetContainer );
2890	configASSERT( pxQueueSetContainer->uxMessagesWaiting < pxQueueSetContainer->uxLength );
2891
2892	if( pxQueueSetContainer->uxMessagesWaiting < pxQueueSetContainer->uxLength )
2893	{
2894	const int8_t cTxLock = pxQueueSetContainer->cTxLock;
2895
2896	traceQUEUE_SEND( pxQueueSetContainer );
2897
2898	/* The data copied is the handle of the queue that contains data. */
2899	xReturn = prvCopyDataToQueue( pxQueueSetContainer, &pxQueue, queueSEND_TO_BACK );
2900
2901	if( cTxLock == queueUNLOCKED )
2902	{
2903	if( listLIST_IS_EMPTY( &( pxQueueSetContainer->xTasksWaitingToReceive ) ) == pdFALSE )
2904	{
2905	if( xTaskRemoveFromEventList( &( pxQueueSetContainer->xTasksWaitingToReceive ) ) != pdFALSE )
2906	{
2907	/* The task waiting has a higher priority. */
2908	xReturn = pdTRUE;
2909	}
2910	else
2911	{
2912	mtCOVERAGE_TEST_MARKER();
2913	}
2914	}
2915	else
2916	{
2917	mtCOVERAGE_TEST_MARKER();
2918	}
2919	}
2920	else
2921	{
2922	pxQueueSetContainer->cTxLock = ( int8_t ) ( cTxLock + 1 );
2923	}
2924	}
2925	else
2926	{
2927	mtCOVERAGE_TEST_MARKER();
2928	}
2929
2930	return xReturn;
2931	}
2932
2933	#endif /* configUSE_QUEUE_SETS */
2934
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source: ctrl/firmware/Main/CubeMX/Middlewares/Third_Party/FreeRTOS/Source/queue.c

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